thermal study of longitudinal and torsional ultrasound phacoemulsification : tracking the...

Download Thermal Study of Longitudinal and Torsional Ultrasound Phacoemulsification : Tracking the Temperature of Corneal Surface, Incision and Handpiece Bokkwan

Post on 21-Jan-2016

212 views

Category:

Documents

0 download

Embed Size (px)

TRANSCRIPT

  • Thermal Study of Longitudinal and Torsional Ultrasound Phacoemulsification: Tracking the Temperature of Corneal Surface, Incision and HandpieceBokkwan Jun MD, John P Berdahl MD, Terry Kim MD*

    Duke University Eye CenterDurham, North CarolinaSupported by a research grant from Alcon, Inc., Consultant, Alcon, Inc.*

  • PurposeTo investigate the change and difference in temperature at the corneal surface, incision, and handpiece Two different modalities of ultrasoundLongitudinalTorsional Two different sizes of incisionStandard (2.75mm) Microincisional (2.2mm) To observe thermal effect on the wounds Operating microscopyScanning electron microscopy (SEM)

  • MethodsProspective studyTwelve human cadaver eyesFour groups of 3 eyes/group Group 1: 2.75mm, 100% longitudinalGroup 2: 2.2mm, 100% longitudinalGroup 3: 2.75mm, 100% torsionalGroup 4: 2.2mm, 100% torsional

    System settings and accessoriesFluidics: Vacuum: 300mmHg, Aspiration: 12cc/min, Bottle height: 100cm and simulated On/Off occlusion approx. every 7 seconds Phacoemulsification time: ~ 40 seconds with full power and instrument manipulation to simulate surgical useTip: Mini-Flared 30 Kelman tipSleeve: MicroSleeve for 2.75mm, UltraSleeve for 2.2mm

  • Thermocamera (ThermaCAMTM, FLIR system, Danderyd, Sweden) Thermal images were captured every 5 secThe temperature of three areas was measuredCorneal surfaceIncisionHandpiece

    Operating microscopyTo observe wound burn with OR microscope (whitening and edema of the wound edge)

    Scanning electron microscopy (SEM) Methods123

  • The average of maximum temperature of incision, handpiece and corneal surface in each group Results

    Max temperature (C)IncisionHandpieceCorneal surfaceGroup 1(2.75mm, 100% longitudinal)45.943.739.5Group 2(2.2mm, 100% longitudinal)47.744.741.9Group 3(2.75mm, 100% torsional)33.227.425.5Group 4(2.2mm, 100% torsional)37.230.229.8

  • ResultsGroup 1 (2.75mm, 100% longitudinal)

    Group 2 (2.2mm, 100% longitudinal)

    Group 1 (2.75mm, 100% torsional)

    Group 1 (2.2mm, 100% torsional)

    Comparison of Thermal images at maximum temperature

  • ResultsTemperature changes of corneal surface, incision and hand pieceGroup 1 (2.75mm, 100% longitudinal)

    Group 3 (2.75mm, 100% torsional)Group 2 (2.2mm, 100% longitudinal)Group 4 (2.2mm, 100% torsional)

    Chart2

    17.620.620.1

    19.232.326.2

    23.636.332.3

    27.838.636.1

    30.940.638

    3342.440.1

    35.145.842

    38.145.343

    39.545.943.7

    38.743.941.4

    37.938.639.2

    Corneal surface

    Incision

    Handpiece

    Time (sec)

    Temperature (C)

    Sheet1

    17.420.322.418.920.923.319.222.125.71921.723.817.620.620.118.120.821.9

    17.929.623.719.532.824.819.831.626.519.529.524.719.232.326.220.23629.8

    20.531.425.721.833.626.721.832.127.420.730.125.823.636.332.32539.734.4

    22.13226.224.134.427.923.732.528.122.930.82727.838.636.129.742.238.5

    23.132.226.925.834.828.624.332.828.624.331.227.630.940.63833.944.440.4

    24.132.72727.435.629.225.7332924.731.728.23342.440.13745.441.9

    24.63327.328.636.229.627.333.329.326.932.528.835.145.84239.346.643.3

    24.833.227.429.636.83027.833.729.426.832.72938.145.34341.347.644.4

    24.43327.429.837.230.229.334.430.127.133.129.139.545.943.741.942.942.9

    25.532.227.53034.73028.332.329.727.330.628.938.743.941.439.639.937.8

    25.126.826.429.831.429.328.530.229.226.127.427.437.938.639.238.838.736.3

    Sheet1

    000

    000

    000

    000

    000

    000

    000

    000

    000

    000

    000

    A/C

    Tip & Wound

    Handpiece

    Time (sec)

    Temperature (C)

    Sheet2

    Sheet3

    Chart1

    18.120.821.9

    20.23629.8

    2539.734.4

    29.742.238.5

    33.944.440.4

    3745.441.9

    39.346.643.3

    41.347.644.4

    41.947.744.7

    39.642.942.9

    38.839.937.8

    Corneal surface

    Incision

    Handpiece

    Time (sec)

    Temperature (C)

    Sheet1

    18.120.821.9

    20.23629.8

    2539.734.4

    29.742.238.5

    33.944.440.4

    3745.441.9

    39.346.643.3

    41.347.644.4

    41.947.744.7

    39.642.942.9

    38.839.937.8

    Sheet1

    000

    000

    000

    000

    000

    000

    000

    000

    000

    000

    000

    A/C

    Tip & Wound

    Handpiece

    Time (sec)

    Temperature (C)

    Sheet2

    Sheet3

    Chart1

    17.420.322.4

    17.929.623.7

    20.531.425.7

    22.13226.2

    23.132.226.9

    24.132.727

    24.63327.3

    24.833.227.4

    24.43327.4

    25.532.227.5

    25.126.826.4

    Corneal surface

    Incision

    Handpiece

    Time (sec)

    Temperature (C)

    Sheet1

    17.420.322.418.920.923.319.222.125.71921.723.8

    17.929.623.719.532.824.819.831.626.519.529.524.7

    20.531.425.721.833.626.721.832.127.420.730.125.8

    22.13226.224.134.427.923.732.528.122.930.827

    23.132.226.925.834.828.624.332.828.624.331.227.6

    24.132.72727.435.629.225.7332924.731.728.2

    24.63327.328.636.229.627.333.329.326.932.528.8

    24.833.227.429.636.83027.833.729.426.832.729

    24.43327.429.837.230.229.334.430.127.133.129.1

    25.532.227.53034.73028.332.329.727.330.628.9

    25.126.826.429.831.429.328.530.229.226.127.427.4

    Sheet1

    000

    000

    000

    000

    000

    000

    000

    000

    000

    000

    000

    A/C

    Tip & Wound

    Handpiece

    Time (sec)

    Temperature (C)

    Sheet2

    Sheet3

    Chart5

    18.920.923.3

    19.532.824.8

    21.833.626.7

    24.134.427.9

    25.834.828.6

    27.435.629.2

    28.636.229.6

    29.636.830

    29.837.230.2

    3034.730

    29.831.429.3

    Corneal surface

    Incision

    Handpiece

    Time (sec)

    Temperature (C)

    Sheet1

    17.420.322.418.920.923.319.222.125.71921.723.8

    17.929.623.719.532.824.819.831.626.519.529.524.7

    20.531.425.721.833.626.721.832.127.420.730.125.8

    22.13226.224.134.427.923.732.528.122.930.827

    23.132.226.925.834.828.624.332.828.624.331.227.6

    24.132.72727.435.629.225.7332924.731.728.2

    24.63327.328.636.229.627.333.329.326.932.528.8

    24.833.227.429.636.83027.833.729.426.832.729

    24.43327.429.837.230.229.334.430.127.133.129.1

    25.532.227.53034.73028.332.329.727.330.628.9

    25.126.826.429.831.429.328.530.229.226.127.427.4

    Sheet1

    000

    000

    000

    000

    000

    000

    000

    000

    000

    000

    000

    A/C

    Tip & Wound

    Handpiece

    Time (sec)

    Temperature (C)

    Sheet2

    Sheet3

  • Comparison of incision temperature with 2.75mm and 2.2mm incision ResultsGroup 1(2.75mm, 100% longitudinal)vsGroup 2 (2.2mm, 100% longitudinal)Group 3 (2.75mm, 100% torsional)vsGroup 4 (2.2mm, 100% torsional)(p=0.002)(p
  • Comparison of incision temperature between longitudinal and torsional groups ResultsGroup 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
  • ResultsOperating 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

  • Results (SEM, endothelial view)SEM images demonstrating wound gap of inner surface and partial loss of Descemets membraneGroup 1 (2.75mm, 100% longitudinal)

    Group 2 (2.2mm, 100% longitudinal)

    Group 3 (2.75mm, 100% torsional)Group 4 (2.2mm, 100% torsional)

  • ConclusionsIncision temperature Can be influenced by ultrasound modality.Was significantly lower in torsional ultrasound as compared to longitudinal ultrasound. To a lesser extent, smaller incisions may also increase incision temperature, but not to a significant degree.

    The combination of torsional ultrasound and small incisionsA safe way to decrease the risk of wound burn in patients with dense cataracts.

    ********

Recommended

View more >