comprehensive ophthalmology free papers - aios edu · coeense too ee es 445 comprehensive...

ComprehensiveOphthalmologyFree Papers

Contents

439

Contents

Comprehensive ophthalmologyA Profile of Ocular Changes in Pregnancy -------------------------------------------445Dr. Madhavi M.R., Dr. Sahithya Tatineni, Dr. Nagasudhamani.M

Colour Vision Problems in The Paintings by Rabindranath Tagore ---------460Dr. Jajneswar Bhunia

Early Rise in Intraocular Pressure (IOP) after Uncomplicated Cataract by Phacoemulsification: A Myth? ------------------------------------------------------------464Dr. Monika Jethani, Dr. Jitendra Jethani, Dr. Ramchandra Kaushik, Dr. Rupa Jain

Ophthalmic Cellphone Imaging System – A Costless Imaging System ---467 Dr. Murali Mohan Gurram

Ultrasound Biomicroscopy as an Important Diagnostic Adjunct in The Management of Limbal Tumors -----------------------------------------------------------469Dr. Ruchi Kabra, Dr. Deepak C. Mehta, Dr. Hansa Thakkar

Comparing Ultrasonic Pachymetry and Anterior Segment OCT (AS - OCT) for Central Corneal Thickness (CCT) --------------------------------------------------- 472Dr. Monika Jethani, Dr. Jitendra Nenumal Jethani, Dr. Aditi Jain, Dr. Rupa Jain

Photographic and Digital Documentation of The Anterior Segment using Compact Digital Camera -------------------------------------------------------------------- 475Dr. Susil Kumar Pani

Hemodynamic Response to Phacoemulsification among Surgeons during High Volume Cataract Surgery ----------------------------------------------------------- 479Dr. Aravind P. Murugesan, Dr. Haripriya Aravind, Dr. Ravichandar A., Dr. Heber A. David

In Vitro Antibiogram of Streptococcus Pneumoniae in Ocular Infections -----483Dr. Priyanka Gogte, Dr. Prashant Garg, Dr. Mukesh Taneja, Dr. Suma N.

Comprehensive Eye Examination in Camps—The Wireless Way ------------486Dr. Shailesh Chandra Suman, Dr. Sil Asim Kumar, Dr.Shoumya Jyoti Datta Mazumder

Comprehensive Ophthalmology Free Papers

445

COMPREHEnSIVE OPHTHALMOLOgy Chairman: Dr. Purendra Bhasin; Co-Chairman: Dr. Saxena Anand

Convenor: Dr. Sreeni Edakhlon; Moderator: Dr. Sharat Babu Chilukuri

A Profile of Ocular Changes in PregnancyDr. Madhavi M.R., Dr. Sahithya Tatineni, Dr. Nagasudhamani.M

To identify the changes in the eye during pregnancy including the eye changes in pregnancy induced hypertension, by testing visual acuity for

distant with snellen’s test types, near vision with Jaeger’s chart, examination of cornea with keratometry for corneal curvature, examination of anterior chamber with slit lamp, intraocular pressure with schiotz tonometer and fundus examination with indirect ophthalmoscope along with hematological parameters.

materials anD methoDsStudy Design: This is a prospective study with randomly selected sample.

The sample size is one hundred and thirty five.

The subjects for the study have been selected from M.B.B.S., students of Mamata Medical College, Khammam, pregnant patients entering OP in Obstetrics department in Mamata Medical Hospital, Khammam by considering the inclusion criteria.

Inclusion Criteria for SelectionControl group1. In the age group of 20-30 years

2. Who attained menarche at normal age 11-15 years (to rule out precocious or delayed puberty)

3. Unmarried with regular and normal menstrual cycles

4. With no specific metabolic disease or chronic disease (elicited through history)

5. With out any refractive errors

6. Not using spectacles for any refractive error presently or previously

Pregnant Women1. In the age group of 20-35 years.

2. With known last menstrual period.

70th AIOC Proceedings, Cochin 2012

446

3. With no specific metabolic disease or chronic disease

4. With regular antenatal check-ups

5. With no history of ( previous) abortion

Not on any treatment of refractive error with spectacles /ocular surgery.

The criterion for selection of pregnancy induced hypertension is based on symptoms, signs of the disease and investigations to evaluate the significance of physiological eye changes during the course of pregnancy.

Prior to the study, each subject was informed in detail of its objectives, the aim of the research protocol and the methods to be used. Their consent was obtained. They were well educated and motivated regarding the procedures so as to extend the best co-operation in various examination protocols. Their information was collected in a proforma. Along with antenatal examinations, local examination of both the eyes was performed by snellen’s test, Jaeger’s chart, is Chihara’s, slit lamp, keratometry, schiotz tonometry and ophthalmoscope.

The Distant Visual Acuity: Measured by Snellen’s chart.

Principle: Two distant points can be visible as separate only when they subtend an angle of 1 minute at the nodal point of the eye.

Procedure: The subject is asked to read the chart with each eye separately and the visual acuity is recorded. Normal person should read at least the 7th line i.e. visual acuity of 6/6 (20/20 in terms of feet/ 20-20 vision).

Visual acuity for near was measured by Jaeger’s chart.

Keratometry / Ophthalmometry or Bausch & Lomb KeratometerPrinciple: The anterior surface of the cornea acts as a convex mirror; so the size of the image produced varies with its curvature. Therefore from the size of the image formed by the anterior surface of cornea (first Purkinje image), the radius of curvature of cornea can be calculated. The accurate measurement of the image size is obtained by using the principle of visible doubling. The radius of curvature of the anterior surface of the cornea is 7.7 - 7.8mm.

Both the eyes of all the patients were examined thoroughly for anterior segment abnormalities with slit lamp bio-microscope. The intraocular pressure was measured with schiotz tonometer (three readings of IOP were measured and the mean was recorded). Pupillary reactions were noted with direct and indirect light reflexes. Fundus findings were recorded with indirect ophthalmoscopy. The media haze was noted, optic discs were examined for their margins, size, and color and cup to disc ratio is evaluated. Retinal blood vessels and background were examined for any pathological changes. Macula and foveal reflexes were observed.


447

Hypertensive retinopathy was graded according to KEITH WAGNER and BAKER classification (1939).

Grade Ι Mild to moderate narrowing or sclerosis of smaller arterioles.

Grade ΙI Moderate to marked narrowing of arterioles, exaggeration of light reflex, changes at the arteriovenous crossings (AV crossings).[deflection of veins at AV crossings (Salu’s sign)]

Grade ΙII Along with grade II changes, copper wiring of arteries, banking of veins distal to AV crossings (Bonnet sign), tapering of veins on either side of AV crossings (Gunn’s sign), cotton wool spots , flame shaped hemorrhages.

Grade ΙV All features of grade ΙΙΙ as well as papilledema.

Blood investigations like fasting/random blood sugar levels (to assess diabetic status), total and differential leucocytic counts and ESR were carried out. Complete macroscopic and microscopic urine examination was conducted to rule out urinary or systemic diseases. Tests for HIV and HbSAg were performed. Blood pressure evaluation was done to assess the hypertension status.

resultsA total of 105 pregnant women visiting the Obstetric out patient department of Mamata General Hospital, Khammam were included in the present study. 30 control group were taken from M.B.B.S students of same age group from Mamata Medical College.

In the present study all the cases observed had normal visual acuity in all the trimesters of pregnancy, but visual disturbance has been observed with loss of vision approaching to 6/36 in eclamptic patients during 30 weeks of pregnancy which has recovered to 6/9 in the postpartum period.

Among 135 patients, 105 patients were observed with increased pigmentation around cheeks and eyelids termed as chloasma.

In this present study, one case of ptosis was observed and the patient was followed for 2 months postpartum which partially improved.

Table 1: Corneal Curvature 1st Trimester 2nd Trimester EyE F-ratio MEAn SD MEAn SD P-value CORNEAL RE 48.719 7.7823 0.050 7.8587 0.012 < 0.001 CURVATURE LE 50.248 7.7900 0.0511 7.8683 0.0136 <0.001

During first trimester the mean corneal curvature in right eye is 7.7823 +/-


448

0.050; in left eye it is 7.7900 +/- 0.0511, During 2nd trimester the mean corneal curvature in right eye is 7.8587 +/- 0.012; in left eye it is 7.8683 +/-0.0136 as shown in Table 1. Here the mean corneal curvature in both the eyes increased from first to second trimester. The estimated P value for 1st trimester and 2nd trimester corneal curvature in both the eyes is < 0.001. There is significant increase in corneal curvature.

Table 2 1st Trimester 3rd Trimester EyE F-ratio MEAn SD MEAn SD P-value CORNEAL RE 48.719 7.7823 0.050 7.8783 0.033 < 0.001 CURVATURE LE 50.248 7.7900 0.0511 7.8867 0.0345 <0.001

During first trimester the mean corneal curvature in right eye is 7.7823 +/- 0.050; in left eye it is 7.7900 +/-0.0511, During 3rd trimester the mean corneal curvature in right eye is 7.8783 +/-0.033; in left eye it is 7.8867+/-0.0345 as shown in table 2. Here the mean corneal curvature in both the eyes increased from first to second trimester. The estimated P value for 1st trimester and 2nd trimester corneal curvature in right and left eye is < 0.001 and < 0.001 respectively. There is significant increase in corneal curvature.

Table 3 1st Trimester PIH EyE F-ratio MEAn SD MEAn SD P-value CORNEAL RE 48.719 7.7823 0.050 7.880 0.040 < 0.001 CURVATURE LE 50.248 7.7900 0.0511 7.8720 0.024 <0.001

During first trimester the mean corneal curvature in right eye is 7.7823 +/- 0.050; in left eye is 7.7900 +/- 0.0511. In PIH the mean corneal curvature in RE is 7.880 ± 0.040; in LE it is 7.8720 ± 0.024. Here the mean corneal curvature is increased in PIH when compared with 1st trimester in both the eyes The estimated P value for 1st trimester and PIH corneal curvature in both the eyes is < 0.001. There is significant increase in corneal curvature.

Table 4 1st Trimester Control EyE F-ratio MEAn SD MEAn SD P-value CORNEAL RE 48.719 7.7823 0.050 7.8090 0.012 0.19 CURVATURE LE 50.248 7.7900 0.0511 7.8133 0.0132 0.048

During first trimester the mean corneal curvature in right eye is 7.7823 ± 0.050; in left eye it is 7.7900 ± 0.0511. In the control group the mean corneal curvature in RE is 7.8090 ± 0.012; in LE it is 7.8133 ± 0.0132 The estimated P value for 1st


449

trimester and control group corneal curvature in right and left eye is 0.19 and 0.048 respectively. There is no significant difference between 1st trimester and control group.

Table 5 2nd Trimester 3rd Trimester EyE F-ratio MEAn SD MEAn SD P-value CORNEAL RE 48.719 7.8587 0.012 7.8783 0.033 0.207 CURVATURE LE 50.248 7.8683 0.0136 7.8867 0.0345 0.260

During 2nd trimester the mean corneal curvature in right eye is 7.8587 +/- 0.012; in left eye is 7.8683 +/-0.0136. During 3rd trimester the mean corneal curvature in right eye is 7.8783 +/- 0.033; in left eye is 7.8867+/- 0.0345. The estimated P value for 2nd trimester and 3rd trimester corneal curvature in both the eyes is 0.2. There is no significant difference between 2nd and 3rd trimester.

Table 6 2nd Trimester PIH EyE F-ratio MEAn SD MEAn SD P-value CORNEAL RE 48.719 7.8587 0.012 7.8800 0.040 0.401 CURVATURE LE 50.248 7.8683 0.0136 7.8720 0.0242 1.000

During 2nd trimester the mean corneal curvature in right eye is 7.8587 +/- 0.012; in left eye it is 7.8683 +/-0.0136. In PIH the mean corneal curvature in RE is 7.880 ± 0.040; in LE it is 7.8720 ± 0.024. The estimated P value for 2nd trimester and in PIH corneal curvature in RE 0.4 and LE 1.000. There is no significant difference between 2nd trimester and PIH.

Table 7 2nd Trimester Control EyE F-ratio MEAn SD MEAn SD P-value CORNEAL RE 48.719 7.8587 0.012 7.8090 0.012 < 0.001 CURVATURE LE 50.248 7.8683 0.0136 7.8133 0.0132 < 0.001

During 2nd trimester the mean corneal curvature in right eye is 7.8587 +/- 0.012; in left eye it is 7.8683 +/-0.0136. In control group the mean corneal curvature in RE is 7.8090 ± 0.012; in LE it is 7.8133 ± 0.0132. Here the mean corneal curvature is increased in 2nd trimester when compared with control group in both the eyes. The estimated P value for 2nd trimester and control group corneal curvature in both the eyes is < 0.001. There is significant increase in corneal curvature.


450

Table 8 3rd Trimester Control EyE F-ratio MEAn SD MEAn SD P-value

CORNEAL RE 48.719 7.8783 0.033 7.8090 0.012 <0.001

CURVATURE LE 50.248 7.8867 0.0345 7.8133 0.0132 < 0.001

During 3rd trimester the mean corneal curvature in right eye is 7.8783 +/- 0.033; in left eye it is 7.8867+/- 0.0345. In control group the mean corneal curvature in RE is 7.8090 ± 0.012; in LE it is 7.8133 ± 0.0132. Here the mean corneal curvature is increased in 3rd trimester when compared with control group in both the eyes. The estimated P value for 3rd trimester and control group corneal curvature in both the eyes is < 0.001. There is significant increase in corneal curvature.

Table 9 3rd Trimester PIH EyE F-ratio MEAn SD MEAn SD P-value CORNEAL RE 48.719 7.8783 0.033 7.8800 0.040 1.000

CURVATURE LE 50.248 7.8867 0.0345 7.8720 0.0242 1.000

During 3rd trimester the mean corneal curvature in right eye is 7.8783 ± 0.033; in left eye it is 7.8867 ± 0.0345. In PIH the mean corneal curvature in RE is 7.880 ± 0.040; in LE it is 7.8720 ± 0.024. The estimated P value for 3rd trimester and PIH corneal curvature in both the eyes is 1.000. There is no significant difference between 3rd trimester and PIH.

Table 10 PIH Control EyE F-ratio MEAn SD MEAn SD P-value CORNEAL RE 48.719 7.8800 0.040 7.8090 0.012 < 0.001 CURVATURE LE 50.248 7.8720 0.0242 7.8133 0.0132 < 0.001

In PIH the mean corneal curvature in RE is 7.880 ± 0.040; in LE it is 7.8720 ± 0.024 In control group the mean corneal curvature in RE is 7.8090 ± 0.012; in LE it is 7.8133 ± 0.0132. Here the mean corneal curvature is increased in PIH when compared with control group in both the eyes. The estimated P value for PIH and control group corneal curvature in both the eyes is < 0.001. There is significant increase in corneal curvature.


451

Comparision of Intraocular Pressure Values

Table 1 1st Trimester 2nd Trimester INTRA EyE F-ratio MEAn SD MEAn SD P-value OCULAR RE 82.828 14.000 0.687 12.440 0.996 < 0.001 PRESSURE LE 115.872 13.520 0.854 12.533 1.097 < 0.001

During first trimester the mean IOP in right eye is 14.000 ± 0.687, in left eye it is 13.520 ± 0.854. During second trimester the mean IOP in RE is 12.440 ± 0.996; in left eye it is 12.533 ± 1.097. Here the mean IOP decreased from first to second trimester. The estimated p value for 1st trimester and 2nd trimester in both the eyes is < 0.001. There is decrease in IOP.

Table 2 1st Trimester 3rd Trimester INTRA EyE F-ratio MEAn SD MEAn SD P-value OCULAR RE 82.828 14.000 0.687 11.620 0.969 < 0.001 PRESSURE LE 115.872 13.520 0.854 11.240 0.906 < 0.001

During first trimester the mean IOP in right eye is 14.000 ± 0.687, in left eye it is 13.520 ± 0.854. During 3rd trimester the mean IOP in RE is 11.620 ± 0.969; in left eye it is 11.240 ± 0.906. Here the mean IOP decreased from first to third trimester. The estimated P value for 1st trimester and 3rd trimester in both the eyes is <0.001. There is decrease in IOP.

Table 3 1st Trimester PIH INTRA EyE F-ratio MEAn SD MEAn SD P-value OCULAR RE 82.828 14.000 0.687 12.720 1.095 0.001 PRESSURE LE 115.872 13.520 0.854 12.760 0.768 0.127

During first trimester the mean IOP in right eye is 14.000 ± 0.687, in left eye it is 13.520 ± 0.854. In PIH the mean IOP in RE is 12.720 ± 1.095; in LE it is 12.760 ± 0.768. Here the mean IOP decreased in PIH when compared with 1st trimester. The estimated P value for 1st trimester and PIH IOP in right and left eye is 0.001 and 0.127 respectively.There is significant decrease in IOP in right eye more then left eye.

Table 4 1st Trimester Control INTRA EyE F-ratio MEAn SD MEAn SD P-value OCULAR RE 82.828 14.000 0.687 15.893 1.201 < 0.001 PRESSURE LE 115.872 13.520 0.854 16.290 1.006 < 0.001


452

During first trimester the mean IOP in right eye is 14.000 ± 0.687, in left eye it is 13.520 ± 0.854. In control the mean IOP in RE 15.893 ± 1.201; in left eye it is 16.290 ± 1.006. Here the mean IOP decreased in 1st trimester when compared with control group. The estimated P value for 1st trimester and control group in both the eyes is <0.001. There is decrease in IOP among 1st trimester group when compared with control group.

Table 5 2nd Trimester 3rd Trimester INTRA EyE F-ratio MEAn SD MEAn SD P-value OCULAR RE 82.828 12.440 0.996 11.620 0.969 0.017 PRESSURE LE 115.872 12.533 1.097 11.240 0.906 < 0.001

During second trimester the mean IOP in RE is 12.440 ± 0.996; in left eye it is 12.533 ± 1.097. During 3rd trimester the mean IOP in RE is 11.620 ± 0.969; in left eye it is 11.240 ± 0.906. Here the mean IOP decreased from second to third trimester. The estimated P value for second and third trimester IOP in right and left eye is 0.017 and < 0.001 respectively. Here the mean IOP decreased in 3rd trimester when compared with 2nd trimester.

Table 6 2nd Trimester PIH INTRA EyE F-ratio MEAn SD MEAn SD P-value OCULAR RE 82.828 12.440 0.996 12.720 1.095 1.000 PRESSURE LE 115.872 12.533 1.097 12.760 0.768 1.000

During second trimester the mean IOP in RE is 12.440 ± 0.996; in left eye it is 12.533 ± 1.097. In PIH the mean IOP in RE is 12.720 ± 1.095; in LE it is 12.760 ± 0.76. The estimated P value for 2nd trimester and PIH in both the eyes is 1.000. There is no significant difference between 2nd trimester and PIH.

Table 7 2nd Trimester Control INTRA EyE F-ratio MEAn SD MEAn SD P-value OCULAR RE 82.828 12.440 0.996 15.893 1.201 < 0.001 PRESSURE LE 115.872 12.533 1.097 16.290 1.006 < 0.001

During second trimester the mean IOP in RE is 12.440 ± 0.996; in left eye it is 12.533 ± 1.097. In control the mean IOP in RE 15.893 ± 1.201; in left eye it is 16.290 ± 1.006. Here the mean IOP decreased in 2nd trimester when compared with control group. The estimated P value for 2nd trimester and control group in both the eyes is < 0.001.

There is significant decrease in IOP.


453

Table 8 3rd Trimester PIH INTRA EyE F-ratio MEAn SD MEAn SD P-value OCULAR RE 82.828 11.620 0.969 12.720 1.095 0.006 PRESSURE LE 115.872 11.240 0.906 12.760 0.768 < 0.001

During 3rd trimester the mean IOP in RE is 11.620 ± 0.969; in left eye it is 11.240 ± 0.906. In PIH the mean IOP in RE is 12.720 ± 1.095; in LE it is 12.760 ± 0.768. The estimated P value for third trimester and PIH IOP in right and left eye is 0.006 and < 0.001 respectively. Here the IOP decreased In 3rd trimester when compared with PIH.

Table 9 3rd Trimester Control INTRA EyE F-ratio MEAn SD MEAn SD P-value OCULAR RE 82.828 11.620 0.969 15.893 1.201 < 0.001 PRESSURE LE 115.872 11.240 0.906 16.290 1.006 < 0.001

During 3rd trimester the mean IOP in RE is 11.620 ± 0.969; in left eye it is 11.240 ± 0.906. In control the mean IOP in RE 15.893 ± 1.201; in left eye it is 16.290 ± 1.006. Here the mean IOP decreased in 3rd trimester when compared with control group. The estimated P value for 3rd trimester and control group in both the eyes is < 0.001. There is significant decrease in IOP.

Table 10 PIH COnTROL INTRA EyE F-ratio MEAn SD MEAn SD P-value OCULAR RE 82.828 12.720 1.095 15.893 1.201 < 0.001 PRESSURE LE 115.872 12.760 0.768 16.290 1.006 < 0.001

In PIH the mean IOP in RE is 12.720 ± 1.095; in LE it is 12.760 ± 0.768. In control the mean IOP in RE 15.893 ± 1.201; in left eye it is 16.290 ± 1.006. Here the mean IOP decreased in PIH when compared with control group. The estimated P value for PIH and control group in both the eyes is < 0.001. There is significant decrease in IOP.A case of uveitis was observed during 24 weeks gestational age presented with chronic non-infectious anterior uveitis with inferiorly distributed brown coloured keratic precipitates, mild flare, and 2+ cells (i.e. 10-20 cells/cu mm). She was instructed not to use any medication. Patient was followed monthly. Uveitis activity gradually decreased during the course of pregnancy and flared up 2 months after postpartum period. This shows that pregnancy has a beneficial effect on uveitis.


454

Among 15 cases of PIH, we found two cases (13.3%) presenting with headache and pedal edema for 6 days. The blood pressure was above 140/100 mmHg and vision was 6/6 for both of the cases. Anterior segment examination was normal. Fundus picture showed hypertensive retinopathy changes like moderate arteriolar narrowing and arteriovenous crossing changes i.e. deflection of veins at AV crossings (Salu’s sign). Diagnosed as Grade ΙΙ Hypertensive retinopathy in both cases.

Two cases presented with serous retinal detachment.

The clinical manifestations of these women are presented here. Patient 1 Patient 2 Age (years) 22 25 Gestational age at the 32 weeks 34 weeks time of admission Blood pressure 160/120 mmHg 180/130 mmHgVisual acuity at the time RE-6/18 RE-6/12 of presentation LE6/60 LE-6/6 RE –localized exudative Retinal edema surrounding Ophthalmologic detachment inferior to macula the macula and small serous examination LE- localized exudative retinal detachment inferior detachment involving macula and temporal to macula excluding fovea, hemorrhagic in right eye is present. spot inferior to macula Left eye is normal Visual acuity in RE-6/6 RE-6/6 postpartum period LE-6/9 LE-6/6 3 weeks postpartum Fundus picture during Retinal detachment Complete recovery is postpartum period was no longer present present without any residual changes within a month of postpartum period

Central Serous Retinopathy Serous Retinal Detachment


455

In this present study we found one case (35 weeks GA) presenting with central scotoma for ten days. Her visual acuity at the time of presentation was 6/12 in right eye and 6/6 in left eye. Anterior segment examination was normal. On fundus examination, there was retinal edema surrounding the macula and white subretinal exudate temporal to the macula in right eye and normal fundus picture in left eye. Right eye was diagnosed as central serous retinopathy. During postpartum period her vision gradually improved and she attained vision of 6/6 in both the eyes. Fundus picture showed resolution of retinal edema, mild mottling and subretinal exudate in right eye.

We found a case presenting with convulsions, 4-5 episodes on the day of presentation. History of associated headache and epigastric pain, pedal edema and facial puffiness was present. Her visual acuity at the time of presentation was 6/36 in both eyes. Anterior segment was normal. Fundus picture showed bilateral disc edema and hemorrhages surrounding the optic disc, cotton wool spots and retinal edema surrounding macula in right eye. The diagnosis was grade ΙV hypertensive retinopathy. During postpartum period her vision improved to 6/12 in both eyes within a month. Fundus picture showed regression of optic disc edema and cotton wool spots.

DisCussionPregnancy is often associated with ocular changes which may be more commonly transient but occasionally permanent.

Visual acuity is one such condition where it is not affected because of the normal refractive status despite the increased corneal curvature and decreased refractive index during normal pregnancy. In the present study all had normal visual acuity in all trimesters of pregnancy except in PIH cases where there is decreased visual acuity which returned to normal in the postpartum period.

Chloasma is a hormonally mediated process, characterized by increased pigmentation around eyes and cheeks. In the present study 105 pregnant women showed chloasma most of them showed around cheeks.

Somani S98 reported a case of unilateral ptosis during and after normal pregnancy. In this present study a case of ptosis was observed and patient followed for 2 months postpartum where the ptosis partially improved.

Corneal CurvaturePark Steve B et. al. prospectively followed 24 women during pregnancy, postpartum period and after cessation of breast feeding. Six (25%) women developed contact lens intolerance during the study period. Statistically significant (P value- 0.05) increase in corneal curvature during the second and third trimester which resolved postpartum was observed.


456

It is seen that corneal curvature increases as the pregnancy advances. According to graph 3 (right eye) and graph 4 (left eye), in the present study there is statistical significant increase in corneal curvature in second trimester (P value-<0.001 in both eyes), third trimester (P value <0.001in both eyes) and PIH (P value<0.001 in both eyes) when compared to first trimester.

There is no significant difference between first trimester and control group (P value RE-0.19, LE- 0.048). There is no significant difference between second trimester, third trimester and PIH cases (P value -1.000), but when compared with control group there is statistical significant increase in corneal curvature.

Intraocular PressureOcular hypotony was observed during normal pregnancy and PIH. Early in the history the ocular hypotensive effect of pregnancy was first recognized in 1922 by Imre and has since been well documented by numerous authors, where it has beneficial effects on glaucoma. Many explanations have been offered for the decreased IOP seen in pregnancy. Becker and Friedenwald, and Paterson and Miller documented significantly increased facility of aqueous out flow in pregnant women. Furthermore, some authors have postulated that reduction in episcleral venous pressure related to the generalized decrease in peripheral vascular resistance in pregnancy may also contribute to lowering the IOP because changes in the elasticity of ligaments and connective tissue occur during pregnancy.Niloofar Ziai et. al. (1994) studied ß-HCG, progesterone, intraocular pressure, aqueous flow during pregnancy among 19 women and found decrease in intraocular pressure during 2nd and 3rd trimester (P< 0.01 and < 0.01), returning to initial levels during postpartum period. They also found the progesterone level increased during pregnancy and decreased during the postpartum period. The ß-HCG levels are highest during the first trimester. He concluded that the progesterone level, but not the ß-HCG, was correlated with intraocular pressure, aqueous flare and corneal thickness.


457

Qureshi IA et. al. (1996) investigated whether or not the high blood pressure found in late pregnancy influences the known ocular hypotensive effect of late pregnancy. In the second and third trimester subjects, they found the mean intraocular pressure was significantly lower than in the non-pregnant control group. The difference between 1st and 2nd, 1st and 3rd, and 2nd and 3rd trimesters of pregnancy were (mean ± s.d) -0.5 ± 1.2(P < 0.05), -1.5 ± 1.7 (P <0.001) and -1.0± 2.1 (P < 0.01) mmHg respectively. In the present study there is statistically significant decrease in IOP during 1st, 2nd, 3rd, trimester and in PIH when compared with controls (P value <0.01). In the present study we found that there is gradual decrease in IOP in 2nd trimester (mean ± s.d) RE- 12.440 ± 0.996, LE- 12.533 ± 1.097 (P< 0.001 in both eyes) and 3rd trimester RE- 11.620 ± 0.969, LE- 11.240 ± 0.906 (P < 0.001 in both eyes) when compared to 1st trimester (mean ± s.d) RE -14.000 ± 0.687, LE- 13.520 ± 0.854. There is also decrease in IOP in 3rd trimester RE- 11.620 ± 0.969, LE- 11.240 ± 0.906 when compared to 2nd trimester RE- 12.440 ± 0.996, LE- 12.533 ± 1.097 (RE- P - 0.01, LE -P< 0.001). Our findings are in conformity with the studies by Qureshi IA.The trend of IOP fall among trimesters when compared with control group was plotted on graph (Figure 1). As when compared to non-pregnant women which is the control group, IOP is seen to be lower in pregnant women. It is seen that IOP falls as pregnancy advances i.e. IOP during 3rd trimester is lower than that of first trimester and second trimester. But it has been seen that in PIH patients IOP is almost equal to that of 2nd trimester. (P - 1.000 in both eyes).

According to Qureshi IA et. al. the mean difference between third trimester hypertensive and third trimester normotensive pregnant women was 0.53 ± 1.5 mmHg (P < 0.05)In the present study the estimated P value between third

Figure 1: IOP Compared among different groups in RE

IOP Compared among Different Groups in LE


458

trimester hypertensive and third trimester normotensive pregnant women was RE- P 0.006, LE -< 0.001.

UveitisC-C Chan et. al. observed four pregnant women in their first trimester with chronic non-infectious uveitis and were followed monthly till 6 months after

delivery. They found uveitis activity decreased after the first trimester, but flared in early postpartum period.

Kubicka-Trzasks A (2004) followed four pregnant women aged 16-21 years with uveitis of unknown etiology. Vitreous flare and cells were present in all cases. They were followed

during pregnancy as well as 3-8 months after delivery. In all patients gradual, total regression of intraocular inflammation with the improvement of visual acuity in three cases were noted. This shows that pregnancy has a positive influence on pregnancy.

A case of uveitis was observed in the present study with unknown etiology during 2nd trimester presented with chronic non-infectious anterior uveitis and was instructed not to use any medication. Flare and cells present. Gradually the activity got reduced during the course of pregnancy and flared up two months after postpartum period. This shows that pregnancy has beneficial effects in pregnancy.

Retinal ChangesSignificant fundus changes are expected in PIH when compared to normal pregnancy. Focal and less often generalized, retinal arteriolar narrowing is the most common ocular change seen in preeclampsia. Early studies by Wagner found these changes in 40% to 100% of preeclampsia patients, but the study of Schreyer found these changes in only 5 out of 106 cases (4.7%) of preeclampsia and in one of 21 severe preelamptic patients. These studies suggest that arteriolar changes may help to distinguish those patients with preexisting chronic hypertension from those with preeclampsia. Sathish S et. al. reported spasm and narrowing of retinal veins in 70% of cases of toxemia.

In the present study we found two cases (13.3%) presenting with headache and pedal edema for 6 days. The blood pressure was above 140/100 mmHg and vision was 6/6 for these cases. Anterior segment examination was normal.


459

Fundus picture showed grade ΙΙ hypertensive retinopathy in both the cases (i.e. moderate arteriolar narrowing and arteriovenous crossing changes).

CSR Gass JDM 35 reported that 90% of pregnant women with central serous retinopathy develop white fibrinous subretinal exudates usually in third trimester. Cruysberg J.R et. al. reported CSR in three pregnant women. All of them presented with central scotoma and symptoms disappeared spontaneously after delivery.In this present study we found one cases (6.6%) (35 weeks GA) presenting with central scotoma for ten days. Her visual acuity at the time of presentation was 6/12 in right eye and 6/6 in left eye. On fundus examination there was retinal edema surrounding macula and white subretinal exudate temporal to macula in right eye and normal fundus picture of left eye. Right eye was diagnosed as central serous retinopathy. During postpartum period her vision was gradually improved and she attained vision of 6/6 in both the eyes. Fundus picture showed resolution of retinal edema, mild mottling and subretinal exudate in right eye.In conclusion the intraocular pressure decreased in 1st, 2nd, 3rd trimester and PIH cases when compared to the control group. Intraocular pressure levels decreased more in 3rd trimester when compared to 1st trimester with P value <0.001. The intraocular pressure values dropped more in 2nd trimester when compared to 1st trimester. There is was a significant difference in IOP values between 2nd and 3rd trimester. IOP levels are almost equal among 2nd trimester and PIH. The IOP values are low in 3rd trimester non-hypertensive when compared to PIH. A case of uveitis was observed which improved during pregnancy and activity flared up following pregnancy. A case of ptosis was observed during pregnancy period which improved in postpartum period. The corneal curvature increased in all trimesters of normal pregnancy and in PIH cases when compared with control group. No significant difference is found between 1st trimester and control group and among 2nd and 3rd trimester. The corneal curvature is more among 2nd trimester and 3rd trimester as compared to 1st trimester (P<0.001). There is no disparity among 2nd trimester and PIH cases (P value RE - 0.4, LE - 1.000). The corneal curvature values are high in PIH as compared to 1st trimester (P <0.001). No significant difference is noted among 2nd, 3rd trimester and PIH cases (P value 1.000).Deviations from normal fundal picture are minimal with normal pregnancy, but significant in PIH. Out of 15 cases there were two cases with arteriolar changes, two with serous retinal detachment, one with central serous chorioretinopathy and one with papilledema. Visual acuity had improved significantly for all the cases following delivery.


460

Colour Vision Problems in The Paintings by Rabindranath TagoreDr. Jajneswar Bhunia

Nobel Laureate Rabindranath Tagore is internationally well known for his extra-ordinary literary works, especially the “Geetanjali”. He had started

drawing sketches and created many color paintings towards the later part of his life. Plenty of comments from many prominent personalities regarding the unusual use of color in Rabindranath’s paintings are available in literatures and biographies.1,2

Tagore met the famous intellectual Romain Rolland at Villeneuve in Italy in July, 1926. According to Rolland, “Tagore said that he could respond very little or not at all to the ‘red’ color. In Italy, Tagore was not at all attracted to the wide fields of red poppy flowers, almost like a spreading fire engulfing the countryside. On the other hand, he used to have immense pleasure in looking at the various shades of blue and violet colors”.2

Stella Kramrisch1 was the famous international art historian from Austria. Rabindranath invited her for teaching the students of Kalabhaban at Shantiniketan. She had spent long time staying within the campus of Shantiniketan around 1920s and closely watched the paintings of Rabindranath. She commented “Reds would be dark or even black while greens would be light in tone, and, in using these colors in ‘conjoint effect’ Tagore would be influenced by differences of tone and perhaps not at all by the differences of colors as we see them.”2,9

John Dalton first reported about defective color vision as an experience of his own color blindness named as “Extraordinary facts relating to the Vision of Colors” in 1794. He had described “That part of the image which others call red appears to me little more than a shade, or defect of light”. In common with his brother he confused Scarlet with Green and Pink with Blue. Dalton supposed that his vitreous humour was tinted blue, selectively absorbing longer wavelengths. He instructed that his eyes should be examined after his death. His family physician did an autopsy examination of the eyes only to find out that the vitreous was perfectly clear. After 150 years David M. Hunt et. al. did a chemical analysis of the old DNA extracted from the preserved eye of John Dalton to arrive at a resolution that the great scientist John Dalton was a Dichromat…….a Deuteranope.3

John Dalton himself was aware of his defective color perception and left a vivid description of his mistakes and confusions in recognizing colors. His preserved eye was also available for DNA analysis. Accordingly David M. Hunt et. al. could conduct a direct chemical analysis of his body tissue as well


461

as compare the phenotype available from Dalton’s own descriptions.

The situation for Rabindranath is different and difficult. We have only his color paintings for study and analysis for arriving at a decision regarding his defective color perception.

Aims of the study is to considering all the above information it was decided to make a thorough search and review of all the available scientific literatures regarding defective color perception of Rabindranath and related articles and analyse them for arriving at a decision. The aims and objectives of this study are:

1. To collect together the research works on the defective color perception of Rabindranath and related articles.

2. Arriving at a decision whether Rabindranath had defective color perception or not.

3. To categorise the type of his color defect if possible.

materials anD methoDsPublished research works and books having the following criteria were collected and studied:

1. Study on the paintings of established color defective painters.

2. Study on the paintings of color defective painter while copying from a normal color painting.

3. Study of the paintings of Rabindranath to find out the evidence of his defective color perception.

Researches on Rabindranth’s defective color perception is scanty and only one such published article was located. However plenty of research works on the colored paintings of color defective artists are available.

An exhaustive book in Bengali language is available displaying the evidences of extensive research works on the defective color perception of Rabindranath Tagore.

All these available informations have been collectively discussed in this study.

results R W Pickford4 has reported about the artist of Edinbugh, Mr. John T. Nicol who was having defective color perception as tested by Ishihara pseudo= isochromatic color plates, Edridge Green Lantern and Pickford Nicholson Anomaloscope. The category of his defect was Protanope. His 12 paintings were analysed by the author. He had a small weakness in the Green/ Blue test but his vision for blue and yellow was not affected. Most of his paintings


462

were mainly using browns and black, but yellow / green and blue were used sometimes. He never used reds and greens together in the same painting.

Charles Meryon,5 an important artist of the 19th century, was color defective that was noted on his medical examination while joining the Navy. Meryon’s famous oil painting “Ghost Ship” reveals the color-defective artist’s typical preference for blue and yellow. He also shifted to the art of etching later in life.

An amateur artist6 was diagnosed as having extreme deuteranomaly using standard clinical tests. The artist limited his palette to short-wave blues and blue-greens and long wave yellow, orange and red. He avoided use of yellow-greens of which he was uncertain. When asked to copy an existing art work by a normal artist, the most obvious area of difficulty he experienced was in reproducing greens and yellow-greens. He especially made mismatches for the colors of red and yellow in shade areas.

Richard Liebreich7 pointed out in a London exhibition of 1871, a painting showed roofs as oxen red on the sunny side but green where shadowed. He suggested that it indicated that the painter was a red–green color vision defective. Angelucci called this “Liebreich’s sign” when he described the works of six painters known to be red–green defectives, whose pictures showed this characteristic.

R. W. Pickford has described that a deuteranomalous artist’s preference in painting was to employ subdued colors in which red and green were used very little or not at all, but can display strong constructional patterns in yellows and blues.7 Protanope’s possible difficulties and faults which might be caused by his peculiarities of color vision are red, may be greatly darkened for him, and red or green, in so far as red can be seen at all, are indistinguishable. What a protanope calls yellow, orange and red are most probably different intensities and saturations of what we should call green. A protanomalous subject, uses red, gold and blue to build strong designs, but very seldom makes any use of green.8

R. W. Pickford and Dr. J. Bose have studied the drawings and paintings of Rabindranath Tagore at Shantiniketan and analysed 5 of his paintings.2 The five pictures they studied were quite compatible with the possibility that Rabindranath Tagore was a protanope, and, indeed, their coloring definitely suggested such a hypothesis. Three of his paintings have been done mainly with very dark colors, such as black or dark brown, sometimes reddish, bluish or purplish, and dark brown and black might be equivalent to red for a protanope in hue. It is evident that none of them show Liebreich’s Sign—red is not represented by green when in shadow in any of them. However Pickford studied Liebreich’s Sign, which is that red where shadowed should be represented by green (1967). He studied 118 pictures by twenty colour vision


463

defective artists and showed that the sign was not a reliable guide.7 Many of the paintings of faces by Rabindranath have displayed an excessive use of dark brown color and that has been described by almost all the literatures in this regard being characteristic of a protanope.

Ketaki Kushari Dyson, Sushovan Adhikary and Robert Dyson have done an extensive research work on the defective color perception of Rabindranath and published a book of more than 800 pages named “Ronger Rabindranath” in this regard in Bengali language. Analysing all the related literatures, personal letters of Rabindranath, comments of relatives and of course many colored paintings by Rabindranath they have concluded Rabindranath to be a protanope.9

In conclusion congenital color vision defect is a genetic disorder and mistakes in the choice of color by a color defective artist are the expression that is the phenotype of his genetic defect. All these studies under consideration are based on the expressions of errors in the choice of colors of a color defective painter, reflected in his created paintings. The conclusion arrived is only on the retrospective study of the phenotypes.We must recall that the study and analysis of the vivid descriptions of Dalton’s own confusions of colors led the researchers to arrive at a decision that Dalton was a protanope. Contrary to this conclusion the chemical analysis of the extracted DNA from Dalton’s preserved eye ultimately established that Dalton was a Deuteranope.3

No tissue sample of Rabindranath is available for the chemical analysis of DNA and so it will be prudent by studying only the phenotype that is the paintings of Rabindranath, only to conclude that Raindranath Tagore was having defective color perception of red=green deficiency.

referenCes 1. Amrit Sen : “Beyond Borders”: Rabindranath Tagore’s Paintings and Visva-Bharati:

Rupkatha Journal Vol. 2 No 1; pp. 34-43.2. R. W. Pickford and J. Bose : colorVision and Aesthetic Problems in Pictures By

Rabindranath Tagore : Bnttsh Journal of Aesthetics, 1987;27:70-5 (winter).3. David M. Hunt, Kanwaljit S. Dulai, James K. Bowmaker, John D. Mollon: The

Chemistry of John Dalton’s color Blindness: Science; 1995;267:984-8. 4. R W Pickford : A color vision defective artist : Brit J Aesthetics 1973;13:384-7. doi:

10.1093/bjaesthetics/13.4.3845. James G. Ravin, MD, Nancy Anderson,and Philippe Lanthony, MD: An Artist with

a Color Vision Defect: Charles Meryon: Survey of Ophthalmology. 1995;39:403-8.6. Barry L Cole Ph D M App Sc BSc LOSc, Jonathan Nathan DSc (hc) MAppSc BSc

LOSC: An artist with extreme deuteranomaly: Clinical and Experimental Optometry 2002;85.5:300-5.


464

7. R W Pickfors : Liebreich’s Sign for Defective color Vision among Artists: Nature 215,542 (29 July 1967); doi:10.1038/215542a0.

8. R W Pickford : The Influence of color Vision defects on Paintings: Brit J Aesthetics 1965;5(3):211-26. doi: 10.1093/bjaesthetics/5.3.211.

9. Ketaki Kushari Dyson, Sushobhan Adhikary and Robert Dyson: Ronger Rabindranath: Ananda Publishers Pvt. Ltd. 1997.

Early Rise in Intraocular Pressure (IOP) after Uncomplicated Cataract by Phacoemulsification: A Myth?Dr. Monika Jethani, Dr. Jitendra Jethani, Dr. Ramchandra Kaushik, Dr. Rupa Jain

There is a rise in intraocular pressure following cataract surgery in the immediate postoperative period.1-4 Various causes like incision size,

trabecular meshwork distortion, trabeculitis, unwashed viscoelastic etc. have been attributed to this rise in IOP in the immediate postoperative period.1-6 The central corneal thickness (CCT) may increase immediate post cataract surgery (phacoemulsification) and corneal hysteresis (CH) has been shown to reduce.7 We did a study to evaluate the immediate postoperative IOP following uncomplicated cataract surgery.

materials anD methoDsA total of 80 patients (80 eyes) were included in this prospective interventional study. All the surgeries were uncomplicated standard cataract surgeries with phacoemulsification. Goldmann applanation tonometer (Zeiss, Germany) was used to measure the preoperative and postoperative IOP at 6 hours postoperative (RK). Ultrasonic pachymeter (Sonomed, India) was used measure the CCT preoperative and immediate postoperatively by one of the authors (MJ). Patients with severe inflammation (cells 2+), corneal edema, visual acuity less than 6/12 at the time of examination were excluded from the study. The findings were recorded and analysed using a microsoft excel sheet.

resultsA total of 80 patients (80 eyes) were included in the study. Mean age of patients was 62.6+/- 10.4 years. Mean CCT preoperative and postoperative was 518.4+/- 33.7 microns and 575.1+/-50.9 microns respectively. Mean IOP before surgery was 16.1+/-3.1 mm of Hg. Mean postoperative IOP was 17.8+/-3.6 mm of Hg. A student t test was performed and P value was 0.03 which is suggestive of a rise


465

in IOP. It is here the importance of CCT comes into the picture. On correcting the preoperative and postoperative IOP with regards to CCT the result was surprising. Mean IOP preoperative on correction with the standard CCT correction chart was 18.1+/-7.5 mm of Hg and postoperatively corrected IOP was 15.8+/-7.4 mm of Hg. Again a student t-test was performed which clearly showed that in fact there was a significant reduction of IOP and the difference was statistically significant.

On further analysis with regards to the type of IOL either rigid IOL (Single piece 5 mm PMMA) or foldable IOL (single piece acrylic hydrophobic) the patients were sub grouped into two. The rigid IOL was implanted in 49 eyes and foldable IOL was implanted in 31 eyes. All the rigid IOLs were of a single company and the foldable IOLs were also of a single company.

The results were surprising. The rigid IOL group has a preoperative CCT of 519.1 +/- 32.2 microns and postoperative CCT of 580.3 +/- 53.2 microns. The preoperative IOP was 15.8 +/- 3.0 mm of Hg and postoperative IOP was 16.3 +/- 6.1 mm of Hg. The P value was 0.6 and was not significant. The CCT corrected IOP was 17.4 +/- 3.9 mm of Hg pre-operatively and postoperatively it was 13.8 +/- 5.7 mm of Hg. The P value was 0.0004 which was highly significant.

DisCussionA lot of work has been done on the change in IOP, CCT and corneal hysteresis following cataract surgery of various types including extraceapsular, small Incision cataract surgery and phacoemulsification;1-7 however, the only few studies have actually correlated and measured CCT7 and its relation to the early postoperative IOP changes.8,9 Bhallil et. al. found decrease in IOP after clear corneal phacoemulsification which was recorded on the 15th day, lst, 2nd, 3rd and 6 months after surgery.10 Sharma et. al.9 found IOP rises significantly on day one in extra capsular cataract surgery and small incision cataract surgery thereafter comes down slightly by day 2 and rapidly by day 7. After 1 week to 3 months, IOP decline is very gradual and there after ceases to decrease. Cohen et. al. observed that 6% of their patients had rise in IOP on the 1st post-op day.

Hager et. al.7 measured CCT and intraocular pressure by non contact tonometry (NCT) and Goldmann applanation tonometry (GAT) in clear corneal cataract surgery. CCT increased from 556.82 +/- 32.5 micron before surgery to 580.26 +/- 45.5 micron after surgery (P < .001). NCT values rose from 17.85 +/- 3.8 mm Hg before surgery to 20.10 +/- 6.3 mm Hg after surgery. GAT values were 14.85 +/- 2.8 mm Hg before surgery and 15.24 +/- 4.1 mm Hg after surgery (P = .52).

Thirumalai et. al.8 measured IOP pre-operatively and 2 hours, 1 day, and 1 week postoperatively. From 1 week before surgery, there was a mean rise in IOP of 8.14 mm Hg 2 hours after surgery followed by a mean fall of 5.18 mm Hg


466

at 24 hours (next-day review). The mean fall in IOP at 1 week was 2.94 mm Hg. 10 percent of patients had an IOP greater than or equal to 35 mm Hg 2 hours postoperatively.

Although a lot of literature has been available on the measurement of postoperative IOP after cataract surgery, none of the studies have been planned properly. Only two studies actually measure the pressure within 6 hours of the surgery. Both the studies Sharma et. al.9 and Thirumalai et. al.8 have not measured CCT and therefore show an increase in the post-op IOP which may be secondary to thicker cornea postoperatively.

Our findings are similar to Hager et. al.7 with regards to increase in CCT after uncomplicated phacoemulsification. Also, GAT readings of their study are similar to our study. They have not tried to compare the reduction of IOP secondary to this rise in CCT post-cataract surgery which is obvious. Other studies failing to measure the CCT do indicate that there is a rise in IOP in immediate postoperative period which gradually falls whereas it is actually the CCT which may gradually reach to preoperative value and thus pseudo-stabilize the IOP.

In conclusion our study clear implicates the rise in CCT postoperatively and links this with the pseudo-rise of IOP recorded immediately after cataract surgery. It is conclusively proved that there is rise in CCT in the immediate postoperative period of an uncomplicated phacoemulsification.

referenCes1. Gormaz A. Ocular tension after cataract surgery. Am J. Ophthalmol 1962;53:832.2. Rich WJ, Radke ND, Cohan BE. Early ocular hypertension after cataract extraction.

Br J. Ophthalmology 1974;58:725.3. Raduis RL, Schultz K, Sobocinski K, Schultz RO, Easom H. Pseudophakia and

intraocular pressure. Am J. Ophthalmol 1984;97:738.4. Gross JG, Meyer DR, Robin AL, Filar AA, Kelly JS. Increased pressure in the

immediate postoperative period after extra capsular cataract extraction. Am J. Ophthalmology 1989;105:466.

5. Kim JW. Comparative study of intraocular pressure change after cataract surgery: phacoemulsification and extra capsular cataract extraction. Korean Journal of Ophthalmology. 1996;10:104-8.

6. Cohen VM, Demetria H, Jordan K, Lamb RJ, Vivian AJ. First day post-operative review following uncomplicated phacoemulsification. Eye (Lond). 1998;1:634-6.

7. Hager A, Loge K, Fullhas MO, Schroeder B, Grhbherr M, Wiegand Wolfgang. Changes in Corneal Hysteresis After Clear Corneal Cataract Surgery. Am J. Ophthalmol 2007;144:341-6.

8. Thirumalai B, Baranyovits PR. Intraocular pressure changes and the implications on patient review after phacoemulsification. J. Cataract Refract Surg. 2003;29:504-7.


467

9. Sharma PD, Madhavi MR. A comparative study of postoperative intraocular pressure changes in small incision vs conventional extra capsular cataract surgery. Eye (Lond). 2010;24:608-12.

10. Bhallil S, Andalloussi I, Chraibi F, Daoudi K, Tahri H. Changes in intraocular pressure after clear corneal phacoemulsification in normal patients. Oman J. Ophthalmol 2009;2:111-3.

Ophthalmic Cellphone Imaging System – A Costless Imaging System Dr. Murali Mohan gurram

Imaging is an important procedure for various purposes. If we want to share our clinical cases with others, the best way for that is with images. A single

image can tell more tales than 100 words. In day to day professional life, we come across many interesting cases. These can be shared with students or others with good images. Imaging is very important for various purposes like teaching, documentation, patient education, progress of disease etc.

Slit lamp imaging system are very expensive with MNC one being approximately 6 lakhs and indigeneous ones approximately 3.5 lakhs. Many of the private practitioners do not have this system. A digital camera can be used for the same purpose, but needs some investment, some hardware modifications and it needs to be carried.

There is a search for an instrument which can give images and doesnot need any extra equipment. I found the answer in my cellphone.

My Cell PhoneMy cellphone is Motorola A1600, which has an effective 2 MP camera. It gives a resolution of 1536 x 2048 pixels. It gives reasonably good images of anterior segment. With little learning we can capture good images of anterior segment. With little extra effort, we can even take Optic disc images. Most important of all, I need not carry any equipment, as my mobile is always in my pocket.

materials anD methoDsI use an old model of Appasamy slitlamp. The imaging is an uniocular procedure. Room lights are switched off for a better contrast. The lesion is focused with necessary slitlamp adjustments. Diffuse light is used for large lesions like pinguecula and pterygium. Slit beam is used for corneal and lens sections. Retroillumination for media opacities. The illumination of slit lamp is reduced to reduce the dazzling light reflex. Lesion is seen uniocularly in both objectives. The objective with better focusing is selected. Low magnification


468

is initially used. The cell phone camera is placed at the respective eyepiece and image is seen on the mobile screen. Minor focusing adjustments are done with micro-movements of joystick. Once the image is focused, click

the button to acquire the image. As many images can be taken as desired. Save the image. Next an image is taken in high magnification (10x). The image gets stored in the memory card of the phone. A memory card of 4 GB can store more than 5000 images.

The images are transferred to the computer through USB ports. They can be transferred to the patients mobile with bluetooth technology (Now a days, most of the mobiles come with this technology).

For the disc images, it is almost the same technique. Slitlamp illumination is not so low. Slit height is reduced to 3 to 5 mm. Use 10x. A rectangular illumination is used as a larger light will reduce the details of image. Focus

Examples of Bitot’s Spot

Early Mid Classic

Festooned Pupil Blood staining of Wiegert’s ring,Ant. Post.Capsule Hyaloid face

PCO Slightly Displaced


469

Ultrasound Biomicroscopy as an Important Diagnostic Adjunct in The Management of Limbal TumorsDr. Ruchi Kabra, Dr. Deepak C. Mehta, Dr. Hansa Thakkar

Clinical assessment to assess the extent and depth of limbal masses with conjunctival and corneal extension is generally crude and the posterior

margins are typically revealed either during surgery or histopathological examination. Pavlin and Foster were the first to describe the use of high frequency ultrasound to examine conjunctival tumors.1 Over time high frequency ultrasound biomicroscopy (UBM) has become a well established method for imaging anterior segment tumors. UBM provides useful information regarding tumor configuration and invasion which prove to be of immense help in deciding the treatment protocol. In our study we report herein the characteristic ultrasonographic features in limbal tumors. Our aim was to assess in a prospective manner the posterior extent and invasion of limbal tumor prior to surgical intervention.

materials anD methoDs63 cases of primary limbal tumors with conjunctival and/or corneal extension were enrolled in our prospective non-randomized study done between 1 April 2008 to 31 March 2011. All patients with limbal tumors and anterior segment tumors are routinely subjected to imaging at the very first visit at our institute.

the disc with 90 D or contact lens biomicroscopy. Its easier with CLB as the eye is stabilized. Focus it uniocularly. Place the mobile over the eyepiece and see the image. Click, once its focused. Its quite difficult to get the right focus. That task is easier with CLB.

For the videos, the procedure is same. Once the lesion is focused. Start the video recording in the cellphone. Place it over the eyepiece. Move the joystick as required. The cellphone keeps focusing the image which gives small jerky movements of the video.

Advantages of Cell Phone Imaging System1. The camera is never forgotten. It is always in your pocket.2. No extra investment.3. Very portable and handy.4. It can be used in your other working places where there is no imaging system.5. Images from a fundus camera can be captured by cell phone.6. Your images are always in your pocket.7. Images of CT scans and MRI scans.8. Easy transferability through “blue tooth” to patient’s mobile. No need for printer.


470

Ultrasound biomicroscopy uses high frequency ultrasonography 50 MHz and requires an eye bath to obtain images. All the patients were scanned in a supine position after anaesthetizing the ocular surface with topical Paracain drops. Photographic record was kept on thermographic paper and in electronic format. These images obtained had 50 micron resolution. A transverse scan is acquired when the back and forth movement of the transducer occurs parallel or tangential to the limbus. Depending on how far anterior the probe sweeps, this movement can produce a cross-sectional image of the cornea, iris, sclera, ciliary body, anterior uveal tissue. For longitudinal scanning the probe movement is rotated 90 degree from the position of the transverse scan. High frequency longitudinal B-Scan cuts are oriented much like the spokes

Table 1Clinicopathological diagnosis no. of patients=54Dermoid 18Lipodermoid 1Nevus 1Melanoma 2Haemangioma 1Squamous cell carcinoma 24CIN 7

Table 2Sl. no. Features - UBM no. of PatientsA Solid Acoustic 58B Internal Pattern Homogenous 47 Hetrogenous 16C Thickness (Mean) mm 2.2D Tumor Shape-Flat 12 Dome 32 Sphere 5 Multinodular 11E Posterior Shadowing 3F Tumor Margin Visibility Posterior 51 Lateral 42G Breach In Descements 3H Involvement of Angle Structures 4 Anteriorchamber Shallowing 4


471

of a wheel with pupil at its centre. Longitudinal and Transverse scans were acquired in all cases in the study.Demographic data including patient age, gender, address were recorded. Tumor features based on slit lamp examination regarding color, size, shape, extent, location, dimension were noted. UBM features were recorded separately. Acoustic features (hollow/solid), internal pattern (homogenous/heterogeneous), tumor configuration (flat, dome, sphere, mixed), tumor dimension, tumor thickness were noted along with extent of posterior and lateral margins. The invasion of descement’s membrane, anterior chamber, cilliary body, anterior choroid by tumor growth was recorded. The extent of posterior shadowing in presence of pigmented masses was noted.

resultsDuring the time interval April 2008-March 2011, 63 patients were examined by us in our prospective study. The mean age was 48 years. 39 were males and 24 were females. Only 54 patients were operated upon and the specific diagnosis according to the clinicopathological data obtained was as follows.Reasonably good quality images delineating the boundaries of the tumor with visualization of the tumor configuration was possible in most of the cases. The tumor surface was hyper-echoic in all patients most likely due to acoustic impedance between water and solid tumor surface. In contrast the stroma was generally hypo-echoic. The other UBM features of all the 63 cases enrolled for the study are as depicted in Table 2.

DisCussionThe utility of routine ultrasonography (10,20 MHz) as an imaging technique for a limbal tumors has limited role as most of the limbal masses are superficial and do not have a deep penetration. Shields et. al. in a comparative study in assessing anterior segment tumors by UBM and anterior segment OCT concluded that for anterior segment tumors UBM offers better visualization of the posterior margin and provides overall better images for entire tumor configuration compared with AS-OCT.2 In our study we found that the detailed imaging of tumor configuration in limbal tumors with high frequency UBM is of immense help in deciding the treatment protocol in our patients also in tumors where deeper invasion of anterior segment tissue is suspected UBM proves to be a very useful diagnostic adjunct due to its ability to penetrate through the lesion into the eye and provide images of the posterior extension of the tumor.

referenCes1. PavLinCJ,MCWhaeJA,MCGowanHD.Ultrasound biomicroscopy of anterior

segment ocular tumors. Ophthalmology 1992:99;1220-8.


472

Comparing Ultrasonic Pachymetry and Anterior Segment OCT (AS - OCT) for Central Corneal Thickness (CCT)Dr. Monika Jethani, Dr. Jitendra Nenumal Jethani, Dr. Aditi Jain, Dr. Rupa Jain

Central corneal thickness (CCT) is an important parameter in ophthalmology in the assessment of corneal disease and for risk profiling in ocular

hypertension and glaucoma. CCT can be measured using a number of modalities including optical pachymetry, ultrasound pachymetry, Scheimpflug imaging, optical coherence tomography (OCT), and even Magnetic Resonance Imaging.1 An extensive meta-analysis of the available literature has shown that mean measured pachymetry values are slightly higher with ultrasonic than with traditional optical pachymetry.2 CCT measured using OCT has been reported in a number of studies using retinal OCT equipment adapted for anterior segment use. Overall, these suggest a similar systematic reduction in comparison with ultrasonic pachymetry, in keeping with the optical basis of OCT.3–5 However, this has not been a consistent finding and other authors have not found a significant difference6 or have even reported thicker CCT by OCT.7

The purpose of this study is to compare CCT measurements using AS-OCT with conventional ultrasonic pachymetry in a prospective manner to investigate the degree of systematic difference and the level of agreement between AS-OCT and ultrasonic pachymetry.

materials anD methoDsFor each of the 90 eyes, at least two horizontal OCT scans of 7 mm fixed depth were obtained and stored for later analysis. CCT measurements were obtained from scans by anterior segment OCT with a Stratus III (Zeiss, Germany, version

2. Carlos Bianciotto, MD, Carol L. Shields et. al.. Assessment of Anterior Segment Tumors with Ultrasound Biomicroscopy versus Anterior Segment Optical CoherenceTomography in 200 Cases. Ophthalmology 2011:118;1297-1302.

3. Paul T Finger et. al. High-Frequency Ultrasonographic Evaluation of Conjunctival Intraepithelial Neoplasia and Squamous Cell Carcinoma. Arch Ophthalmol. 2003;121:168-72.

4. D H Char, G Kundert, R Bove, J B Crawford 20 MHz high frequency ultrasound assessment of sclera and intraocular conjunctival squamous cell carcinoma. Br J. Ophthalmol 2002;86:632–5.

5. Tunc M, Char DH, Crawford JB, et. al.. Intraepithelial and invasive squamous cell carcinoma of the conjunctiva: analysis of 60 cases. Br J. Ophthalmol 1999;83:98–103.


473

6.0.3) using the corneal reflectivity profile. The central cornea was identified from the peak of the reflectivity profile on the horizontal axis. The calipers were then aligned on the peak reflections at the anterior and posterior boundaries of the cornea, in the axis of the corneal apex. The two measurements were averaged for right eye only to avoid any bias. Ultrasound testing was also performed twice for right eye only. The cornea was first anesthetized with one drop of pro-paracaine hydrochloride 0.5% (Paracain, Sunways, India). It would be very difficult to assess whether the two instruments took measurements at the same exact location. However, to ensure that ultrasound CCT was measured at the center of the cornea, we placed the probe tip at the very center of the cornea and kept the pachymeter horizontal. If the patient moved and the probe decentered, then the measurements were repeated. Ultrasound pachymetry was performed in each case by one of two authors (Dr. MJ and Dr. AJ) to measure the inter individual variability. Ten sequential measurements were obtained from the center of the cornea and averaged. Values with standard deviation (SD) of 5 micron or less were considered suitable for inclusion.

Statistical Analysis. Pearson correlation was used to assess the strength of correlation of the two measurements. The measurements were also compared with the paired t-test. Since AS-OCT measurements involved caliper measurements made by the observer all eyes were remeasured by a second observer to study inter observer agreement.

resultsMean age was 32.9 +/- 16.1 years with 41 male and 49 female patients. Mean CCT with ultrasonic pachymetry for observer 1 and 2 were 523.2 +/- 28.6 microns and 522.5 +/- 30.9 respectively. Mean CCT with AS-OCT for observer 1 and 2 were 526.6 +/- 26.7 and 525.8 +/- 26 microns respectively. The value with AS OCT is slightly higher than with ultrasonic pachymetry but the P value is not significant. The P value was 0.405 and 0.436 between ultrasonic pachymetry and AS OCT for observer 1 and 2 respectively which is not significant.

Correlation coefficient between ultrasonic pachymetry and AS-OCT was 0.95 (observer 1) and 0.93 (observer 2). Correlation between the two observers, to assess the inter individual variability for ultrasonic pachymetry and AS-OCT was 0.96 and 0.97 respectively.

DisCussionDoughty and Zaman2 (300 patients) found that mean normal CCT was 530 microns for slit-lamp-based optical pachymetry and 544 microns for ultrasonography. Subsequent reports using retinal OCT adapted for the anterior segment3–5 suggest a similar effect; other authors have reported no significant difference6 or even thicker measurements of CCT by OCT.7


474

AS-OCT has the advantages over ultrasonic pachymetry in that it is a noninvasive, non contact modality, as well as having the ability to examine other structures as mentioned above. The disadvantage is that it is slower to perform in a busy clinic than a hand-held pachymeter and requires greater expertise. Unlike ultrasonic pachymetry, AS-OCT can easily be used to assess regional differences in the cornea and the facility for the patient to fixate on a target allows more accurate identification of the central corneal surface.

Zhao et. al.8 has reported CCT using AS-OCT found a systematic difference between AS-OCT and ultrasonic pachymetry. It is unclear whether ultrasound or OCT measurements more accurately reflect the true corneal thickness. Kim et. al.9 presented their data with another AS-OCT machine that is SL-OCT (Heidelberg Eye Explorer v1.5.9.0) and found that though the correlation was excellent between the two machine 0.82 there was a significant difference in the average standard deviation (SD) around 26.3 micron and the AS-OCT measurements were slightly lower than the pachymetry measurements. Our measurements showed that there was excellent correlation between the two methods and the AS-OCT showed a minimally higher value which has been reported earlier by Fishman et. al..6 and Leung et. al..7 We did not see much difference in the SD range also and the two methods correlated well for both the observers separately.

For OCT, uncertainty of the true index of refraction of infrared radiation in the cornea may create a source of error in calculating the CCT.8 There could also be small calibration errors in either system.

In conclusion, AS-OCT is a promising non contact and reproducible diagnostic method that is comparable to ultrasonic pachymetry in the evaluation of corneal thickness and the inter observer variability is low, though the AS-OCT may been slightly more time consuming but has the advantage of being totally noninvasive.

referenCes1. Wolffsohn JS, Davies LN. Advances in anterior segment imaging. Curr Opin

Ophthalmol 2007;18:32–8.2. Doughty MJ, Zaman ML. Human corneal thickness and its impact on intraocular

pressure measures: a review and metaanalysis approach. Surv Ophthalmol 2000;44:367–408.

3. Wirbelauer C, Scholz C, Hoerauf H, et. al.. Noncontact corneal pachymetry with slit-lamp–adapted optical coherence tomography. Am J. Ophthalmol 2002;133:444-50.

4. Wong AC, Wong CC, Yuen NS, Hui SP. Correlational study of central corneal thickness measurements on Hong Kong Chinese using optical coherence tomography, Orbscan, and ultrasound pachymetry. Eye 2002;16:715–21.


475

5. Bechmann M, Thiel MJ, Roesen B, et. al. Central corneal thickness determined with optical coherence tomography in various types of glaucoma. Br J. Ophthalmol 2000;84:1233–7.

6. Fishman GR, Pons ME, Seedor JA, Liebmann JM, Ritch R. Assessment of central corneal thickness using optical coherence tomography. J. Cataract Refract Surg. 2005;31:707–11.

7. Leung DY, Lam DK, Yeung BY, Lam DS. Comparison between central corneal thickness measurements by ultrasound pachymetry and optical coherence tomography. Clin Experiment Ophthalmol 2006;34:751–4.

8. Zhao PS, Wong TY, Wong W-L, et. al. Comparison of central corneal thickness measurements by Visante anterior segment optical coherence tomography with ultrasound pachymetry. Am J Ophthalmol 2007;143:1047–9.

9. Kim HY, Budenz DL, Lee PS, Feuer WJ, Barton K. Comparison of Central Corneal Thickness using Anterior Segment Optical Coherence Tomography vs Ultrasound Pachymetry. Am J Ophthalmol 2008;145:228–32.

Photographic and Digital Documentation of The Anterior Segment using Compact Digital CameraDr. Susil Kumar Pani

The aim of the study is to simplify the process of documentation of the diseases of the anterior segment of the eye by the use of easily available

compact digital camera.

methoDs anD materialsEvery eye care professional uses a slit lamp bio-microscope to examine the anterior segment of the eye. To document, the slit lamp needs to have a standard beam splitter, image capturing device or a digital camera back fitting on to the beam splitter, video, audio interface, all connected to a standard desktop computer. Most of them come with proprietary software to capture and edit the photograph. The whole system other than slit lamp costs minimum of Rs 100,000 from the Indian companies and more than Rs 300,000 from abroad. I have tried to use the ordinary digital camera which is easily available in market from standard known companies available from Rs 5000 to Rs 10,000 very easily. In my study I have used Sony compact camera model DSC W520. This camera is a 14 MP camera costing about Rs 8000 at the beginning of study. I will describe the camera controls to be used in documenting the slit lamp photography. The routine method used by me is to place the compact camera tightly against the eye piece of the slit lamp while the bio-microscope and the light are already sharply focused on the area to be photographed. One will be able to see the live picture on the screen of the camera before capturing the image.


476

Camera ControlsISO: The ISO represents the sensitivity of the film or sensor to light. Normally the option given is auto ISO, 100, 200, 400, 800, 1600 and rarely 3200 or more. The higher the number, the more sensitive is the ability to capture the image. As you increase the ISO, pictures can be taken at low light conditions. This will produce a graininess of the picture. Hence for slit lamp photography set the ISO always 100 or 200 or maximum at 400.

White BalanceThis feature deals with the type of light used for lighting the object photographed. To be more precise it means the color temperature of the light falling on the object. The options available in a compact digital camera is auto white balance, day light, cloudy, fluorescent under natural white light, incandescent light and flash. In auto white balance setting the camera tries to recognize the color temperature of the light falling on the object and sets the white balance. Incandescent white balance is when the light source is an ordinary bulb or a Halogen light. As most of the slit lamps use the Halogen bulb as the light source, this is the white balance to be used for slit lamp photography. Flash can be used for gross photography of the eye and the face. Otherwise while taking photos, the slit lamp is used as the source of the light and magnification, hence the white balance to be used is always incandescent light.

FocusThe compact digital cameras give option of multiple auto focus points and central auto focus point. In the multi auto focus points the camera tries to focus on the entire exposed screen. In case of central auto focus the camera focuses only at the centre of the object in front of the camera. In case of slit lamp photography it is better to use the central auto focus mode keeping the area of interest right at the centre of the frame. In case of taking general photograph of eye or face one can use multi auto focus mode.

Metering ModeMost compact digital cameras provide at least 3 metering modes. Metering mode means the exposure time to capture the image. This exposure time is decided by two main factors, the shutter speed and aperture. Three to be precise, the ISO, shutter speed and aperture. The shutter speed is the amount of time the aperture remains open to capture the image. The lower the shutter speed the more is the exposure, faster the shutter speed lesser is the exposure. Aperture is the size of the opening through which the light reaches the film or the sensor. The aperture is otherwise called F stop. The larger the aperture the more the exposure, the smaller the aperture the less is the exposure. The aperture is designated as 1.2, 1.8, 2.8, 3, 3.5, 4….22. The lower the number is the larger aperture and the larger the number the narrower the aperture. The


477

metering modes usually available are multi, central and spot in case of most of compact digital cameras. In the multi metering mode the exposure is decided by taking reading of light falling on entire frame to be captured. In case of central metering the exposure is calculated on the brightness or light falling at the centre of the frame to be captured. Spot metering decides the exposure of the brightness of the small central point. In case of high end compact cameras and digital SLR the spot in the frame can be changed by the user. In case of slit lamp photography it is best to use either central or spot meter to get the correct exposure of the picture taken.

Exposure CompensationIt is important to use a compact digital camera with a facility to adjust the exposure. In this one can increase or decrease the brightness from the exposure reading mode by the camera. In slit lamp photography the Halogen light falling on the eye and viewed through the slit lamp is quite bright at the centre and the surrounding areas are reasonably dark. Hence the camera metering is fooled to believe that there is less light. Hence the exposure in normal mode results in washout of all the details in the centre which is the main area to be captured and documented, this happens even when spot metering is used. Hence most of the time it is essential to reduce the exposure to either -1 or -2 steps below the exposure reading made by the camera.

Steady ShotThis reduces the vibration of the hand while taking the picture and should be always on

Image SizeIn principle always use the highest resolution available in the camera for capturing the images.

FlashMost compact cameras gives multiple options of using the in built flash. They are usually auto flash, flash ON, slow synchronization flash and flash OFF. In documenting the anterior segment through the slit lamp always set the flash to OFF mode. In case of direct photographing the eye and the face the flash can be set at either mode OFF or flash ON.

ZoomAlways use the optical zoom to a minimum extent to maintain good depth of field.

DROIn DRO OFF mode there is no recovery of the shadow details. In case of slit lamp photography always put OFF the DRO, as the area of interest is already brightly lit with slit lamp light.


478

Picture Capture ModesMost of the standard compact cameras provide multiple modes to take pictures. Some of standard modes available are scene selection mode, complete


479

auto mode, program auto mode and rarely full manual mode. In the scene selection mode it provides for multiple options like: landscape mode, twilight mode, portrait mode, beach mode and high brightness mode. In complete auto mode the camera decides all the settings including the ISO, Metering, Focus, Aperture, Shutter, White Balance and others. For general purpose photography full auto is acceptable to get average results. In program auto mode the camera can be adjusted (set by the photographer) for the parameters like ISO, White Balance, Exposure Compensation, Metering, flash, focus, etc. but the camera decides the aperture and shutter speed. In full manual mode in addition one can also control the aperture, shutter speed or both. Some cameras allow additional features to control the exact color temperature in white balance, exposure bracketing etc. Hence from above features it always better to use either the programme auto mode with adjustable settings or full manual mode to take pictures in the slit lamp to get the best results.

Most of the entry level compact cameras record the picture in JPEG format which is a compressed form of recording the picture data but is good enough.

resultsA sample collage of picture are attached in the end.

DisCussionI have used a simple digital camera available to document the diseases of the anterior segment of the eye through the slit lamp to get consistent excellent results. I hope this will help all eye care professionals to use them even if they do not have access to an anterior segment imaging system.

referenCe1. Fogla R, Rao Sk ophthalmic photography using digital camera. Indian journal

ophthalmology 2003:51-269-72.

Hemodynamic Response to Phacoemulsification among Surgeons during High Volume Cataract SurgeryDr. Aravind P. Murugesan, Dr. Haripriya Aravind, Dr. Ravichandar A., Dr. Heber A. David

Surgical Procedures are mentally demanding and every surgeon feels the strain subjectively. This may be especially true in this high volume tertiary

care setup where the average surgeon performs about 1500 cataract surgeries per year.


480

The autonomic nervous system is a major determinant of the functional properties of the heart in that it alters spontaneous sinus node de polarization and cardiac rhythm, which can be assessed by the rhythm of the sinus node. The variations of the surgeon’s heart rate in comparison to their respective baseline and the blood pressure were the chosen parameters to monitor physical and mental states and to measure the sympathovagal balance.

The purpose of this study to investigate the individual hemodynamic response to the stress of performing routine Phacoemulsification (PE) among normal, healthy ophthalmic surgeons in a high-volume setup.

materials anD methoDsIn a tertiary eye care institution, 14 qualified ophthalmologists who were trained in performing PE were recruited in the study. They were selected across different age groups, gender and levels of experience. Each of them was examined by a general physician and pre-existing systemic complaints were recorded. The blood glucose, total cholesterol and hemoglobin for all participants were noted. For surgeons over 40 years of age, a baseline electrocardiogram was also recorded. The baseline blood pressure and heart rate of the surgeons was recorded in a calm, non-operating room setup on three different occasions by an examiner. In the operating room (OR) the surgeons were explained the procedure and consent was obtained. They were then connected to an electronic multi-monitor under their sterile surgical gowns. The surgeons underwent continuous electronic monitoring of their hemodynamic parameters while performing multiple PEs during the course of the operating day. Each surgery was divided into five serial stages – Wound construction, Capsulorrhexis, Phacoemulsification, Irrigation-aspiration and IOL implantation. The heart rate (HR) corresponding to each stage and blood pressure (BP) at the end of each surgery were recorded by the anesthesiologist. Since the third stage was the longest, the maximum and minimum heart rate were noted and their average taken for calculation.

resultsThe difference of the heart rate from the established baseline to the particular step in surgery was calculated for every individual and averaged for the total number of surgeries performed in that single day. Mean pulse difference from baseline peaked during stage 3 (Phacoemulsification stage) consistently for all surgeons. However the change in BP over the course of multiple surgeries analyzed using repeated measures ANOVA was not significant. The group was stratified based on age, gender, experience and number of surgeries performed on that particular day. The analysis showed no statistical significance but it was possible to see the difference between individual surgeons over their


481

performance curves. Among this group, two surgeons showing consistently high HR during surgery were re-examined and counseled for stress management by the physician.

DisCussionMental strain in the operating room is very difficult to define and to measure. Measuring heart rate variability (HRV) is currently the best method of assessing mental strain and is more sensitive than measuring heart rate alone. Needless to say, ophthalmic surgeons are always under tense mental and socio-legal strain to yield optimum results for their patients. The results themselves could be assessed from various points of view. Quantitative and qualitative audits of performance of ophthalmic surgeons are of intense general interest and under critical surveillance in this institution.


482

This study observed two facts. One was that the rise in heart rate of the surgeons, an indicator of strain in response to stress and problems, was the highest in the Phacoemulsification stage of all operations and is fairly stabilized before and after it. This tendency was observed throughout the operating day while performing relatively straightforward PE cases. Second was that most of the surgeons did not show any alarming rise in heart rate or blood pressure at any stage of surgery, contrary to our expectations. Two surgeons had high heart rates and this was probably a reflection of their personality.Each of the surgeons is capable of performing 15 to 30 cataract surgeries continuously on a single operating theatre turn. The high output is facilitated by a team of well trained, dedicated middle level ophthalmic personnel (MLOP). They organise the OR, escort the patients, clean and drape them, assist in surgery and verify the biometry and identity of the patient. This streamlines the system and allows the surgeon to focus only on the surgery at hand. It is implied that this smooth operation of the high volume cataract surgery assembly line enhances surgeon comfort and enables them to perform multiple surgeries with the least mental stress.The limitations of this study include that it measured heart rate and not HRV, as continuous Holter monitoring of surgeons was not feasible. This limitation could be overcome by a future study measuring the HRV of several surgeons.In summary, this study is the first report to measure and evaluate the intra-operative hemodynamic changes of ophthalmic surgeons as a measure of their mental state and equilibrium.In conclusion Surgeons’ stress in PE is reflected in excitement of the cardiovascular system. Though it varies among individuals, PE stage seems uniformly hemodynamically significant. A planned support system, trained staff and OR tranquility ensure minimal mental stress.Financial Interest: The authors do not have any financial interest in any of the equipment, medications or techniques mentioned above.

referenCes1. Min-Ho Song et. al. Intra-operative heart rate variability of a cardiac surgeon

himself in coronary artery bypass grafting surgery. Interact Cardio Vasc Thorac Surg. 2009;8:639-41.

2. Payne RL, Rick JT. Heart rate as an indicator of stress in surgeons and anesthetists. J. Psychosomatic Res. 1986;30:411–20.

3. Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology. Heart rate variability: standards of measurement, physiological interpretation, and clinical use. Circulation 1996;93:1043–65.

4. Becker WG, Ellis H, Goldsmith R, Kaye AM. Heart rates of surgeons in theatre. Ergonomics 1983;26:803–7.


483

In Vitro Antibiogram of Streptococcus Pneumoniae in Ocular InfectionsDr. Priyanka gogte, Dr. Prashant Garg, Dr. Mukesh Taneja, Dr. Suma N.

The eye may be infected from external sources or through intraocular invasion of micro-organisms that are carried by the blood stream.1 External

bacterial infections of the eye are usually localized but may frequently spread to other tissues. The eyelid and conjunctiva have a normal microbial flora controlled by its own mechanism and by the host. Modification of this normal flora contributes to ocular infections such as blepharitis, conjunctivitis, canaliculitis, orbital cellulitis, endophthalmitis, etc.Timely institution of appropriate therapy must be initiated to control the infections and thereby minimize ocular morbidity. If they are not treated promptly, it may lead to sight threatening condition.2 For this timely intervention, it is essential to correctly identify the causative organism with the help of a thorough microbiological work up and then initiate the therapy based on the sensitivity pattern of the organism. However to a community based ophthalmologist without access to a laboratory set up, the information of common ocular pathogens and the trends in the current antibiotic sensitivity pattern form the basis of treatment initiation. Also it has been observed that the causative organisms and their response to antibiotic therapy is not static and varies according to their geographic location. Thus it is essential to periodically study these parameters and revise treatment protocols.3,4

Streptococcus pneumoniae is a Gram positive cocci and is the main cause of central corneal ulceration among bacterial keratitis in South India.5 According to another study from a tertiary care center in South India, Gram positive organisms accounted for 69.1% of all bacterial isolates with Streptococcus pneumoniae being one of the 5 most common causative organisms. Therefore, the purpose of this article is to study the in vitro antibiotic sensitivity pattern of Streptococcus pneumoniae in ocular infections.

materials anD methoDsRetrospective analysis of microbiology records of patients clinically diagnosed and treated for ocular infections between January 2010 and December 2010 was done. All culture positive samples of significant growth of Streptococcus pneumoniae were included in the study and the antibiotic susceptibility was determined using the Kirby-Bauer disc diffusion test.Corneal scrapings were obtained using standard techniques6 with a sterile Bard Parker blade (#15). Collection of vitreous samples was done in a standard manner. The samples were inoculated directly onto sheep blood agar, chocolate agar, thioglycolate, and brain heart infusion broth. These media


484

were incubated at 37°C. The blood agar plates were each incubated under aerobic and anaerobic conditions and chocolate agar was incubated in 5% carbon dioxide. Media and nutrients to enable growth of fungi and parasites (Acanthamoeba) were also included as part of the standard corneal scraping culture protocol, as was microscopic evaluation of corneal smears by Gram stain, Giemsa stain, KOH preparation and KOH with calcofluor white under fluorescence. Acid-fast stains (Ziehl-Neelsen and Kinyoun) and immuno-cytochemistry stains were performed when indicated.The identification of Streptococcus pneumoniae was made on the basis of colony morphology on culture medium which showed the presence of alpha hemolytic colonies on blood agar. The smear showed the presence of lanceolate, diplococcic. The culture was considered positive when there was growth of the same organism on two or more media, confluent growth at site of inoculation on one solid medium, growth in one medium with consistent direct microscopy findings, or growth of the same organism on repeated sampling. In vitro susceptibility testing was performed by Kirby-Bauer disc diffusion method and interpreted using Clinical and Laboratory Standards Institute’s serum standards. The antibacterial agents (Hi-media Laboratories Pvt. Ltd., Mumbai, India) used were amikacin (30 μg/disk), tobramycin (10 μg/disk), gentamicin (10 μg/disk), cefazolin (30 μg/disk), cephotaxime (30 μg/disk), ceftazidime (30 μg/disk), ciprofloxacin (5 μg/disk), norfloxacin (10 μg/disk), ofloxacin (5 μg/disk), gatifloxacin (5 μg/disk), moxifloxacin (5 μg/disk), chloramphenicol (30 μg/disk) and vancomycin (30 μg/disk) and were consistently tested for their efficacy against standard American Type Culture Collection (ATCC) bacteria (Staphylococcus aureus ATCC 25923, Str. pneumoniae ATCC 49619, Haemophilus influenzae ATCC 49241, Ps. aeruginosa ATCC 27853, Escherichia coli ATCC 25922) as a general quality control laboratory procedure. Susceptibility was graded as resistant (R), intermediate sensitivity (I), or sensitive (S).

resultsDuring the study period 4597 samples were submitted for microbiology evaluation and 122 were culture positive for Streptococcus pneumomiae. Of these the 58.2% samples were collected from males and the remaining 42.8% from female patients showing a slight male preponderance. The main source of samples was corneal scrapings accounting for 86.88% of the samples. Vitreous samples from clinically diagnosed cases of endophthalmitis accounted for 9.01% of the cases while 4.09% samples were from other sources like endonasal swabs, eviscerated contents etc.

The antibiotic susceptibility in decreasing order was as follows Cefazolin (99.19%), Vancomycin (98.38%), Cefuroxime and Gatifloxacin (97.58%), Moxifloxacin (95.16%), Chloramphenicol (94.35%), Ofloxacin (92.74%)


485

and Ciprofloxacin (90.32%). Amikacin and Gentamicin showed the least susceptibility with 8.06% and 33.87 % respectively. Also 27.41% samples were susceptible to all tested antibiotics. This pattern is consistent with those reported in other studies from similar and varied geographic location.2,4

In conclusion as consistent with other reports, Streptococcus pnuemoniae is one of the important etiological factors for ocular infections and needs the initiation of prompt anti bacterial treatment. To our knowledge this is the first isolated analysis of in vitro susceptibility pattern of Streptococcus pnuemoniae. It can be concluded that this species shows a high susceptibility to Cefazolin and Vancomycin and therapy with these agents can be effective in controlling the ocular infections. Also fluoroquinolones still maintain a good susceptibility for this Gram positive organism and can be considered in the treatment initiation.

It must be noted that these are in-vitro results, and one of the limitations of using in-vitro antibiotic sensitivity as a surrogate for in-vivo effectiveness is that antibiotic sensitivities do not always mirror the clinical response to an antibiotic for a variety of reasons, including direct topical delivery, corneal penetration of an antibiotic and host factors.3 However this study provides a guide for treatment and would be helpful in initiating treatment where microbiology facilities are not available. However this should not replace the appropriate microbiology investigations and specific antibiotic treatment initiation based on culture and sensitivity wherever feasible.

referenCes1. Williamson-Noble FA, Sorsby A. Etiology of the eye diseases; developmental

defects; heredity. In: Conrad B, editor. The Eye and Its Diseases. 2nd ed. Philadelphia: W. B. Saundars Company; 1950. pp. 309–21.

2. Wolfgang Haas, Chris M. Pillar, Mohana T, et. al. Monitoring Antibiotic Resistance in Ocular Microorganisms: Results From the Antibiotic Resistance Monitoring in Ocular MicRorganisms (ARMOR) 2009 Surveillance Study. Am J. Ophthalmol 2011;152:567–574

3. Sharma S, Kunimoto DY, Garg P, Rao GN. Trends in antibiotic resistance of corneal pathogens: Part I. An analysis of commonly used ocular antibiotics. Indian J. Ophthalmol 1999;47:95-100

4. M Jayahar Bharathi, R Ramakrishnan, C Shivakumar, R Meenakshi and D Lionalraj . Etiology and antibacterial susceptibility pattern of community-acquired bacterial ocular infections in a tertiary eye care hospital in south India. Indian J Ophthalmol. 2010 Nov-Dec; 58(6): 497–507.

5. M Srinivasan, Christine A Gonzales, Celine George, et. al. Epidemiology and aetiological diagnosis of corneal ulceration in Madurai, south India. British Journal of Ophthalmology 1997;81:965–971

6. Jones DB, Liesegang TJ, Robinson NM. Laboratory Diagnosis of Ocular Infections. Washington DC: Cumitech 13, American Society for Microbiology; 1981.


486

Comprehensive Eye Examination in Camps—The Wireless WayDr. Shailesh Chandra Suman, Dr. Sil Asim Kumar, Dr.Shoumya Jyoti Datta Mazumder

The eye camps in India are almost synonymous to cataract screening. Often non- cataract conditions are missed out. Most of the eye screening camps

in rural India are carried out with the help of torch light only and by the ophthalmic technicians. With the help of wireless instruments (like portable slit lamp, indirect ophthalmoscope and Perkin’s tonometer) and ophthalmic team (comprising vision technician, ophthalmic assistant/optometrist, nurses, counsellor and doctors) a difference can be made. We had done study on ”comprehensive eye screening camps - the wireless way” to evaluate effectiveness of detecting non-cataract conditions during cataract screening in rural outreach camps. The patients were mostly from under served population, so need of comprehensive eye examination was immense for them. During three consecutive camps many non-cataract blinding conditions like glaucoma suspect and diabetic retinopathy were detected and sent to the base hospital for proper diagnosis and treatment. Wireless instruments have great value in comprehensive eye screening in large volume with reasonable time, cost and man-power.

Rational of the study is while giving too much stress on cataract many a time we miss non-cataract blinding eye conditions and later regret. Comprehensive eye examination with reasonable utilization of time, cost, and man-power we can add value to cataract screening by picking up glaucoma suspects and different retinopathies co-existing with cataract. Wireless instruments like portable slit lamp, cordless indirect ophthalmoscope tremendously help in comprehensive examination in a shorter time. This study examines the effectiveness of this examination process.

Aim and objectives of the study is (i) To evaluate the effectiveness of using wireless instruments in comprehensive eye screening in large volume outreach camps in terms of cost, man power and time. (ii) To evaluate the ability of the process to detect non-cataract blinding conditions like glaucoma and different retinopathies and prevent blindness.

materials anD methoDs This was a retrospective cross sectional study to evaluate the effectiveness of wireless instruments in cataract screening camps to detect non-cataract conditions like glaucoma, Diabetic and other retinopathies. It was done in Purba Medinipur district of West Bengal in 3 consecutive camps. A regular


487

comprehensive eye screening team comprised vision technician, ophthalmic assistant/optometrist, laboratory technician, nurses, counsellor and doctors conduct the examination using wireless instruments (Schiotz’s tonometer, Perkin’s tonometer, portable slit lamp, indirect and direct ophthalmoscope) and basic tools for refraction. The camps were done on 3 consecutive Sundays between February 6, 2011 and February 20, 2011. A total number of 1323 patients attended the camps comprising all age groups. All the 1323 patients attending the camps had detailed examinations including history (ocular and systemic) refraction where indicated, tonometry and dilated fundus examination. Pupil was not dilated in case of shallow anterior chamber. Fundus examination was not possible in mature and hypermature cataract, infective conditions. Glaucoma was suspect in eyes with high IOP, suspicious cup-disc ratio. Retinal changes were correlated with systemic diseases. Patients were counselled about the eye conditions and prognosis explained. Patients with posterior segment abnormalities were further examined at base hospital before cataract surgery to establish the diagnosis, explain prognosis and plan treatment.

In our team, usually two ophthalmologists, 2-3 refractionists, 7-9 nurses, 1-2 lab. technician, 2 counsellor are needed for a screening camp of 400-500. One ophthalmologist is posted per expected 150-200 patients. Travel time is a major consideration. One refractionist is posted per expected crowd of 150 (roughly 50 out of 150 would need refraction). Usually 400-450 patients attend per screening camp. Usually 7-9 nurses are needed for a screening camp of 400-500, to perform vision testing, syringing, blood pressure recording, tonometry, and to assist doctors in clinical examination. 1-2 pathology laboratory technician is/are posted for urine/blood sugar examination. Local volunteers help to manage registration and patient flow.

resultsTotal number of patients screened were 1323 out of which 581(43.92%) were male and 742(56.08%) were female. 630 patients (47.6%) had operable cataract. Out of 630(47.6%) cases 278(44.13%) were males and 352(55.87%) were females. Out of 630 cataract cases 45(7%) were glaucoma suspects, 24(3.8%) had Diabetic retinopathy and 21(3.3%) had other retinopathies. Among 693(52.4%) non-operable cases, 51(7.35%)were glaucoma suspects, 27(3.90%)cases were Diabetic retinopathy and 25(3.60%) cases had other retinopathies. So the above results show that substantial amount of patients were Glaucoma suspects or had Diabetic retinopathy and other retinopathies. In this way, this study tells the role of comprehensive eye examination even at high volume camps to detect non-cataract conditions and the usefulness of wireless instruments in doing so in optimal time. Screening started at 8-9 am and finished at 4-5 pm with 45 min. lunch break. Totally it takes 8-10 hrs/day.


488

DisCussionAs we know that 80% blindness is avoidable (preventable plus curable). In a country like India 70% people live in rural area and one third are below the poverty line and have poor access to service. Most of the rural people might know about cataract only, but they don’t know about other leading causes of blindness like Glaucoma, Diabetic retinopathy, etc. Most of the cataract camps are limited to only cataract screening. Comprehensive eye examination at camps is an effective way to overcome this problem. In high volume situations matching time with quality is an issue. With the help of wireless instruments detection of non-cataract conditions become faster and easier. The strengths of our study are – (i) screening of non-cataract conditions like glaucoma suspects, DR etc. (ii) finding the effectiveness of wireless instruments in comprehensive eye examination in large volume situation. (iii) creating awareness about other causes of blindness in the rural population who attend the camp.

In conclusion comprehensive eye examination is extremely important from blindness prevention point of view. Wireless instruments are light, portable and easy to operate. These instruments are very effective in managing high volume situation in remote areas.

Recommendation: All screening camps particularly in rural areas should have wireless instruments with the ophthalmic team and it should be done in a comprehensive way so that non-cataract conditions are not missed out and blindness is prevented.

referenCes1. Community Eye Health J. 2006:19:22-3.2. Indian Journal of Community Medicine 2010;35:355-358.3. Community Eye Health 2002;14:4-6.4. Http://Www.Curableblindness.Org/Region/South-Asia/India.Html.

comprehensive ophthalmology free papers - aios edu · coeense too ee es 445 comprehensive...

Documents