One-year follow-up of toric intraocular lensimplantation in forme fruste keratoconus

Alejandro Navas, MD, Raul Suarez, MD

We present 2 cases of toric intraocular lens implantation for keratoconus: A 55-year-old man withforme fruste keratoconus with a preoperative uncorrected distance visual acuity (UDVA) of 20/800and a refraction of�6.50�3.00�135 and a 46-year-old man with a claw-shaped topographic pat-tern, a family history of keratoconus, and a UDVA of 20/800 with a refraction of�5.00�3.00�85.The refraction had been stable for at least 5 years in both patients. Phacoemulsification and im-plantation of an acrylic toric IOL were uneventful. One year postoperatively, the UDVA was 20/25 inboth cases, with a refraction of �0.25�0.50�140 and 0.25�0.50�60, respectively. No progres-sion and no IOL rotation were observed. Toric IOLs may provide excellent outcomes in patientswith stable and nonprogressive corneal ectasia.

J Cataract Refract Surg 2009; 35:2024–2027 Q 2009 ASCRS and ESCRS

CASE REPORT

The current treatment options for patients with ectaticcorneas vary depending on the severity of the disease.They include spectacles, contact lenses, intrastromalrings, keratoplasty (penetrating or lamellar), crosslink-ing,1–3 refractive lens exchange with intraocular lens(IOL) implantation,4 phakic IOL implantation, anda combination of these. Some authors have used exci-mer laser surgery in patients with keratoconus, but thesafety of the procedure is controversial.5

The AcrySof toric SN60TT IOL (Alcon, Inc.) can pro-vide good results in patients with astigmatism.6 Thesingle-piece acrylic IOL is implanted in the capsularbag. Three toric powers are available in 3 models:T3, T4, and T5, which correct 1.50 diopters (D), 2.25 D,

Submitted: March 27, 2009.Final revision submitted: May 10, 2009.Accepted: May 13, 2009.

From the Department of Cornea and Refractive Surgery, Institute ofOphthalmology ‘‘Conde de Valenciana,’’ Mexico City, Mexico.

Neither author has a financial or proprietary interest in any materialor method mentioned.

Presented in part at the Association for Research in Vision and Oph-thalmology, Fort Lauderdale, Florida, USA, April 2008, and at theRefractive Surgery Subspecialty Day at the annual meeting of theAmerican Academy of Ophthalmology, Atlanta, Georgia, USA,November 2008.

Corresponding author: Alejandro Navas, MD, Department of Corneaand Refractive Surgery, Institute of Ophthalmology ‘‘Conde deValenciana,’’ Chimalpopoca #14, Col Obrera, Mexico City, Mexico06800. E-mail: babesian@gmail.com.

Q 2009 ASCRS and ESCRS

Published by Elsevier Inc.

2024

and 3.00 D, respectively, in the IOL plane.7 The spherepower of these IOLs ranges from C6.0 to C30.0 D.Additional models with higher cylinder powers willsoon be available.

Few reports about toric IOLs in patients with kerato-conus have been published. We report 2 cases of non-progressive keratoconus that had refractive lensexchange with capsular bag toric IOL implantationfor the correction of myopia and irregular astigma-tism. The follow-up in both cases was at least 1 year.

CASE REPORTS

Case 1

A 55-year-old man requested refractive surgery. He hadwell-controlled arterial hypertension and denied any otherdisease. His refraction had been stable for the previous 10years. The uncorrected distance visual acuity (UDVA) inthe left eye was 20/800, with a manifest refraction of �6.50�3.00�135 and a corrected distance visual acuity (CDVA)of 20/30. Orbscan II (Bausch & Lomb) corneal topographyand Pentacam (Oculus) Scheimpflug images showed anasymmetric bowtie and indices of keratoconus (Figure 1, Aand B). The ophthalmic examination was within normallimits. The central corneal thickness was 544 mm.

Calculation for a toric IOL was performed with the IOL-Master (Carl Zeiss Meditec AG) using the SRK/II formulafor emmetropia and the AcrySof toric IOL online software(Available at: http://www.acrysoftoriccalculator.com. Ac-cessed July 5, 2009) (Figure 1, C). The IOLMaster axial lengthand Orbscan II keratometric readings were used along withthe default induced surgeon astigmatism, which the soft-ware considered as 0.5 D. Using 40.30 @ 134 in the flat axisand 43.40 @ 44 in the steep axis, the calculation was C11.0C3.0� 45. Phacoemulsificationwas performed uneventfullyusing the chip-and-flip technique. A Mendez degree gauge(Katena Products, Inc.) was used to intraoperatively mark

0886-3350/09/$dsee front matter

doi:10.1016/j.jcrs.2009.05.043

2025CASE REPORT: TORIC IOLS IN FORME FRUSTE KERATOCONUS

Figure 1. Case 1, left eye. A: Orbs-can II keratometric map showingtopographic astigmatism. B: Ocu-lus Pentacam showing frontal cur-vature Scheimpflug images of theastigmatism. C: Toric IOL softwarecalculation with suggested IOL po-sition.D: Final IOL position. NoticeIOL marks align according to thesuggested position.

the horizontal axis at 0 and 45 degrees (implantation IOLaxis) with a previous superior reference mark to avoid cyclo-torsion misalignment. A 2.8 mm clear corneal incision wasperformed at 150 degrees (surgeon preference) under topicalanesthesia. The toric IOLwas aligned according to themarks(Figure 1, D). A combination of topical ciprofloxacin–dexa-methasone was used for 1 week postoperatively. At 1week, theUDVAwas 20/25 and remained stablewith aman-ifest refraction of �0.25 �0.50 � 140 for 15 months. No lensrotation was observed.

The right eye also had inferior steepening (Figure 2,A andB) with a UDVA of 20/400, improving to 20/25 with a�7.50sphere. Phacoemulsification and implantation of an asphericIOL obtained aUDVAof 20/25. Subjectively, the patient wasvery satisfied with both eyes even though he needed an addto achieve the best near visual capacity.

Case 2

A 46-year-old man requested refractive surgery. He hada positive family history of keratoconus in an uncle andhad had a stable refraction for at least 5 years. The UDVAin the right eye was 20/800 with a manifest refraction of�5.00�3.00� 85 and a CDVAof 20/30. Corneal topographyand Scheimpflug images showed a claw-shaped pattern(Figures 3, A and B). Exotropia of 10 prism diopters wasfound; the rest of the examination of both eyes was withinnormal limits. The central corneal thickness was 471 mm.

Using Orbscan II keratometric readings of 43.8 @ 8 in theflat axis and 45.8 @ 174 in the steep axis and the default sur-geon’s induced astigmatism, the toric IOL calculation wasC13.50 C2.25 � 6. Phacoemulsification was performed un-eventfully, and the toric IOL was aligned according to the

J CATARACT REFRACT SURG

marks (Figure 3,D). The UDVAwas 20/25 at 1 week and re-mained stable for 12 months, with a manifest refraction of0.25�0.50� 60. The fellow (left) eye also had a claw-shapedpattern (Figure 4, A and B) and a UDVA of 20/200 witha manifest refraction of �1.50 �1.50 � 95. It was decidednot to treat the left eye. The patient was very satisfied withthe result using monovision even though the left eye wasthe dominant eye.

DISCUSSION

Although there are several new effective techniques tocorrect astigmatism,7,8 irregular astigmatism con-tinues to be challenging, particularly in patients withcorneal ectasia. We present 2 eyes of 2 patients withforme fruste keratoconus in whom we used in-the-bag toric IOLs to correct the refractive error. Vision im-proved significantly in both cases and remained stableduring a 12-month follow-up. An important limitationof this study is the small number of cases. Althoughthere are a few reports of silicone toric IOL implanta-tion in patients with keratoconus with good results,9

to our knowledge, there are no reports of AcrySof toricimplantation in patients with ectatic corneas.

Toric IOLs are used ideally in patients with regularastigmatism,6,8 and we decided to use them in ourcases because both patients had a stable ectatic pattern.Progression is difficult to predict, but as Krachmer10

commented, age and mechanical eye rubbing are im-portant factors that affect progression. After any

- VOL 35, NOVEMBER 2009

2026 CASE REPORT: TORIC IOLS IN FORME FRUSTE KERATOCONUS

Figure 2. Case 1, right eye. A: Orbs-can II showing inferior steepeningon the keratometric map. B: OculusPentacam frontal curvature imageshowing a more evident inferiorsteepening.

surgery, patients tend to avoid rubbing their eyes andtherefore may experience less or no progression. Wepresented cases with low risk for progression; in thehypothetical scenario that these cases present signifi-cant progression, corneal transplantation would prob-ably be required, during which the IOL could be easilyremoved and replaced with any other IOL.

Another good option in patients such as ours isphakic IOL implantation. Recently, Kamiya et al.11 re-ported 2 cases in which phakic toric Collamer IOLswere implanted in 2 patients with keratoconus.

Unfortunately, these patients will need another proce-dure if they develop cataract. Phakic IOLs must beused in younger patients, although the age-cut decisionis controversial and debatable. It is also important toconsider the cost effectiveness of 2 procedures duringa lifetime versus one that solves the refractive problem.

Clinically, we have not seen any IOL rotation usinga conjunctival landmark as a reference. Althoughsome studies show that IOL rotation is less than 4 de-grees,6,12,13 we should evaluate changes in patientswith abnormal corneas more meticulously.

Figure 3. Case 2, right eye. A: Orbs-can II keratometric map showingtopographic astigmatism. B: Ocu-lus Pentacam showing frontal cur-vature Scheimpflug images of theastigmatism. C: Toric IOL softwarecalculation with suggested IOL po-sition.D: Final IOL position. NoticeIOL marks align according to thesuggested position.

J CATARACT REFRACT SURG - VOL 35, NOVEMBER 2009

2027CASE REPORT: TORIC IOLS IN FORME FRUSTE KERATOCONUS

Figure 4. Case 2, left eye. A: Orbs-can II keratometric map witha claw-shaped pattern. B: OculusPentacam frontal curvature imageshowing irregular astigmatism.

Some authors avoid corneal refractive surgery inpatients who are keratoconus suspects or those witha family history of keratoconus.14 We believe that inthese cases and in carefully selected cases of nonpro-gressive keratoconus, toric IOLs may be an excellentalternative.

REFERENCES1. Rabinowitz YS. Keratoconus. Surv Ophthalmol1998; 42:297–319

2. Tan BU, Purcell TL, Torres LF, Schanzlin DJ. New surgical

approaches to the management of keratoconus and post-LASIK

ectasia. Trans Am Ophthalmol Soc 2006; 104:212–218; discus-

sion, 219–220. Available at: http://www.pubmedcentral.nih.gov/

picrender.fcgi?artidZ1809910&blobtypeZpdf. Accessed July 5,

2009

3. Wollensak G. Crosslinking treatment of progressive keratoco-

nus: new hope. Curr Opin Ophthalmol 2006; 17:356–360

4. Leccisotti A. Refractive lens exchange in keratoconus. J Cata-

ract Refract Surg 2006; 32:742–746

5. Kasparova EA, Kasparova AA. Six-year experience with exci-

mer laser surgery for primary keratoconus in Russia. J Refract

Surg 2003; 19:S250–S254

6. Horn JD. Status of toric intraocular lenses. Curr Opin Ophthalmol

2007; 18:58–61

7. Amesbury EC, Miller KM. Correction of astigmatism at the time

of cataract surgery. Curr Opin Ophthalmol 2009; 20:19–24

8. Sun X-Y, Vicary D, Montgomery P, Griffiths M. Toric intraocular

lenses for correcting astigmatism in 130 eyes. Ophthalmology

2000; 107:1776–1781; discussion by RM Kershner, 1781–1782

J CATARACT REFRACT SURG

9. Sauder G, Jonas JB. Treatment of keratoconus by toric foldable

intraocular lenses. Eur J Ophthalmol 2003; 13:577–579

10. Krachmer JH. Potential research projects; Castroviejo lecture.

Cornea 2007; 26:243–245

11. Kamiya K, Shimizu K, Ando W, Asato Y, Fujisawa T. Phakic toric

implantable Collamer lens implantation for the correction of high

myopic astigmatism in eyes with keratoconus. J Refract Surg

2008; 24:840–842

12. Weinand F, Jung A, Stein A, Pfutzner A, Becker R, Pavlovic S.

Rotational stability of a single-piece hydrophobic acrylic intraoc-

ular lens: New method for high-precision rotation control. J Cat-

aract Refract Surg 2007; 33:800–803

13. Zuberbuhler B, Signer T, Gale R, Haefliger E. Rotational stability

of the AcrySof SA60TT toric intraocular lenses: a cohort study.

BMC Ophthalmology 2008; 8:8. Available at: http://www.

biomedcentral.com/content/pdf/1471-2415-8-8.pdf. Accessed

July 5, 2009

14. Navas A, Ariza E, Haber A, Fermon S, Velazquez R, Suarez R.

Bilateral keratectasia after photorefractive keratectomy. J Re-

fract Surg 2007; 23:941–943

First author:Alejandro Navas, MD

Department of Cornea and RefractiveSurgery, Institute of Ophthalmology‘‘Conde de Valenciana,’’ Mexico City,Mexico

- VOL 35, NOVEMBER 2009