thermal study of longitudinal and torsional ultrasound phacoemulsification : tracking the...
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Thermal Study of Longitudinal and Thermal Study of Longitudinal and Torsional Ultrasound Torsional Ultrasound PhacoemulsificationPhacoemulsification::
Tracking the Temperature of Corneal Tracking the Temperature of Corneal Surface, Incision and HandpieceSurface, Incision and Handpiece
Bokkwan Jun MD, John P Berdahl MD, Terry Kim MD*Bokkwan Jun MD, John P Berdahl MD, Terry Kim MD*
Duke University Eye CenterDuke University Eye CenterDurham, North CarolinaDurham, North Carolina
Supported by a research grant from Alcon, Inc., Consultant, Alcon, Inc.*
PurposePurpose To investigate the change and difference in To investigate the change and difference in
temperature at the corneal surface, incision, temperature at the corneal surface, incision, and handpieceand handpiece Two different modalities of ultrasoundTwo different modalities of ultrasound
• LongitudinalLongitudinal• Torsional Torsional
Two different sizesTwo different sizes of incisionof incision• Standard (2.75mm) Standard (2.75mm) • Microincisional (2.2mm)Microincisional (2.2mm)
To observe thermal effect on the woundsTo observe thermal effect on the wounds
Operating microscopyOperating microscopy Scanning electron microscopy (SEM) Scanning electron microscopy (SEM)
MethodsMethods Prospective studyProspective study
Twelve human cadaver eyesTwelve human cadaver eyes Four groups of 3 eyes/group Four groups of 3 eyes/group
• Group 1:Group 1: 2.75mm, 100% longitudinal 2.75mm, 100% longitudinal• Group 2:Group 2: 2.2mm, 100% longitudinal 2.2mm, 100% longitudinal• Group 3:Group 3: 2.75mm, 100% torsional 2.75mm, 100% torsional• Group 4:Group 4: 2.2mm, 100% torsional 2.2mm, 100% torsional
System settings and accessoriesSystem settings and accessories Fluidics: Fluidics: Vacuum: 300mmHg, Aspiration: 12cc/min, Bottle height: Vacuum: 300mmHg, Aspiration: 12cc/min, Bottle height:
100cm and simulated On/Off occlusion approx. every 7 seconds100cm and simulated On/Off occlusion approx. every 7 seconds Phacoemulsification time: Phacoemulsification time: ~ 40 seconds with full power and ~ 40 seconds with full power and
instrument manipulation to simulate surgical useinstrument manipulation to simulate surgical use Tip: Tip: Mini-Flared 30° Kelman tipMini-Flared 30° Kelman tip Sleeve: Sleeve: MicroSleeve for 2.75mm, UltraSleeve for 2.2mmMicroSleeve for 2.75mm, UltraSleeve for 2.2mm
ThermocameraThermocamera (ThermaCAM(ThermaCAMTMTM, FLIR system, Danderyd, Sweden), FLIR system, Danderyd, Sweden)
Thermal images were captured every 5 secThermal images were captured every 5 sec The temperature of three areas was measuredThe temperature of three areas was measured
1.1. Corneal surfaceCorneal surface2.2. IncisionIncision3.3. HandpieceHandpiece
Operating microscopyOperating microscopy To observe wound burn with OR microscopeTo observe wound burn with OR microscope (whitening and edema of the wound edge)(whitening and edema of the wound edge)
Scanning electron microscopyScanning electron microscopy (SEM)(SEM)
MethodsMethods
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The average of maximum temperature of incision, The average of maximum temperature of incision, handpiece and corneal surface in each grouphandpiece and corneal surface in each group
ResultsResults
Max temperature (°C)
IncisionIncision Handpiece Corneal surface
Group 1(2.75mm, 100% longitudinal)
45.945.9 43.7 39.5
Group 2Group 2(2.2mm, 100% longitudinal)(2.2mm, 100% longitudinal)
47.747.7 44.744.7 41.941.9
Group 3(2.75mm, 100% torsional)
33.233.2 27.4 25.5
Group 4(2.2mm, 100% torsional)
37.237.2 30.2 29.8
ResultsResultsGroup 1 Group 1 (2.75mm, 100% longitudinal) Group 2 Group 2 (2.2mm, 100% longitudinal)
Group 1 Group 1 (2.75mm, 100% torsional) Group 1 Group 1 (2.2mm, 100% torsional)
Comparison of Thermal images Comparison of Thermal images at maximum temperatureat maximum temperature
ResultsResults Temperature changes of corneal surface, incision and Temperature changes of corneal surface, incision and
hand piecehand pieceGroup 1 Group 1 (2.75mm, 100% longitudinal)
Group 3 Group 3 (2.75mm, 100% torsional)
Group 2 Group 2 (2.2mm, 100% longitudinal)
Group 4 Group 4 (2.2mm, 100% torsional)
15
20
25
30
35
40
45
50
<0 0-5 5-10 10-15 15-20 20-25 25-30 30-35 35-40 40-45 45-50
Time (sec)
Tem
pera
ture
(°C
)
Corneal surface
Incision
Handpiece
15
20
25
30
35
40
45
50
<0 0-5 5-10 10-15 15-20 20-25 25-30 30-35 35-40 40-45 45-50
Time (sec)
Tem
pera
ture
(°C) Corneal surface
Incision
Handpiece
15
17
19
21
23
25
27
29
31
33
35
37
39
<0 0-5 5-10 10-15 15-20 20-25 25-30 30-35 35-40 40-45 45-50
Time (sec)
Tem
pera
ture
(°C
)
Corneal surface
Incision
Handpiece
1517192123
2527293133353739
<0 0-5 5-10 10-15 15-20 20-25 25-30 30-35 35-40 40-45 45-50
Time (sec)
Tem
pera
ture
(°C) Corneal surface
Incision
Handpiece
Comparison of incision temperature with 2.75mm and 2.2mm incision
ResultsResults
15
20
25
30
35
40
45
50
<0 0-5 5-10 10-15 15-20 20-25 25-30 30-35 35-40 40-45 45-50
Time (sec)
Tem
pera
ture
(C)
2.75, 100% longitudinal
2.2, 100% longitudinal
Group 1
(2.75mm, 100% longitudinal)
vs
Group 2
(2.2mm, 100% longitudinal)
Group 3
(2.75mm, 100% torsional)
vs
Group 4
(2.2mm, 100% torsional)
(p=0.002)
(p<0.001)
15
20
25
30
35
40
45
50
<0 0-5 5-10 10-15 15-20 20-25 25-30 30-35 35-40 40-45 45-50
Time (sec)
Tem
pera
ture
(°C
)
2.75, 100% torsional
2.2, 100% torsional
Comparison of incision temperature between longitudinal and torsional groups
ResultsResults
15
20
25
30
35
40
45
50
<0 0-5 5-10 10-15 15-20 20-25 25-30 30-35 35-40 40-45 45-50
Time (sec)
Tem
pera
ture
(C
)
2.75 longitudinal
2.75 torsional
15
20
25
30
35
40
45
50
<0 0-5 5-10 10-15 15-20 20-25 25-30 30-35 35-40 40-45 45-50
Time (sec)
Tem
pera
ture
(C
)
2.2 longitudinal
2.2 torsional
Group 1
(2.75mm, 100% longitudinal)
vs
Group 3
(2.75mm, 100% torsional)
Group 2
(2.2mm, 100% longitudinal)
vs
Group 4
(2.2mm, 100% torsional)
(p<0.001)
(p<0.001)
ResultsResults
Operating microscopy
Group 1 and 2 (longitudinal US groups)• Wound burn (whitening and edema of the
wound edge) was observed in 6/6
• Incision temperature was 43~45 when ℃the first sign of wound burn was observed
Group 3 and 4 (torsional US groups)• No wound burn was evident in 0/6
ResultsResults (SEM, endothelial view)(SEM, endothelial view) SEM images demonstrating wound gap of inner surface SEM images demonstrating wound gap of inner surface
and partial loss of Descemet’s membraneand partial loss of Descemet’s membrane
Group 1 Group 1 (2.75mm, 100% longitudinal) Group 2 Group 2 (2.2mm, 100% longitudinal)
Group 3 Group 3 (2.75mm, 100% torsional) Group 4 Group 4 (2.2mm, 100% torsional)
ConclusionsConclusions
Incision temperatureIncision temperature Can be influenced by ultrasound modality.Can be influenced by ultrasound modality. Was significantly lower in torsional ultrasound as Was significantly lower in torsional ultrasound as
compared to longitudinal ultrasound. compared to longitudinal ultrasound. To a lesser extent, smaller incisions may also increase To a lesser extent, smaller incisions may also increase
incision temperature, but not to a significant degree.incision temperature, but not to a significant degree.
The combination of torsional ultrasound and The combination of torsional ultrasound and small incisionssmall incisions A safe way to decrease the risk of wound burn in A safe way to decrease the risk of wound burn in
patients with dense cataracts.patients with dense cataracts.