Hitting the Axis for Astigmatism Correction

Transcription

1 Hitting the Axis for Astigmatism Correction Bryan S. Lee, MD, JD 40 th Annual Dallas Spring Ophthalmology Symposium April 27, 2018 Consultant: Allergan, Katena, New World Medical

2 Financial Disclosures I have no relevant financial relationships with the manufacturers of any commercial products and/or providers of commercial services discussed in this activity.

3 Why It Matters Every degree of error from the intended axis of astigmatism correction reduces the effectiveness of the correction by 3.3% (Sanders, Grabow, Shepherd 1992)

4 Monofocal Pseudoaccommodating Multifocal

5 Marking accuracy Mark width IOL placement Postplacement rotation Stackable Error

6 Biometry and keratometry Manual data transfer from office to OR Pre-op marking 180 axis Surgical marking of target axis Toric IOL alignment 1. Head tilt with topography/keratometry 2. Data transfer (office O.R.) 3. Mark patient (sitting up, need level marks) 4. Identify axis in the O.R. (cyclotorsion, degree gauge) 5. Pen marks 5+ degrees wide, fade

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12 Marking the Axis

13 LRI Axis Marking

14 Toric Axis Marking & Adjustment

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16 Other Markerless Systems Verion (Alcon): preoperative imaging + surgical microscope overlays for positioning and centration

17 Results Prospective, nonrandomized series (Daniel Black, ASCRS 2015) Tecnis toric IOL 507 with ink (pre-august 2014) v. 161 with CallistoPost-op cyl (D) Cyl 0.5D Cyl 0.75D ink 0.18 ± % 98% markerless 0.17 ± %* 100%

18 Results Prospective, randomized trial (Webers, JCRS 2017) 36 eyes Alcon toric with manual marking v. Verion Less misalignment in digital group (p=0.02) 94% within 5 degrees at POH1 v. 81%

19 Benefits of Markerless Systems Time/workflow More accurate Reduces stackable error Less time spent on intraoperative aberrometry Verifying IOL position after viscoelastic removal Helps with small pupil cases Multifocal IOL centration

20 Integration with Aberrometry Talbot-Moiré interferometry (ORA) Wavefront passes through a pair of gratings at a set distance and angle to each other, creating a fringe pattern Non-physiologic conditions: edema, lid speculum, IOP/IOL position

21 Integration with Aberrometry Hatch JRS 2015: retrospective, toric IOL autoks, optical biometry, online calculator (n=27) 2 nd group +ORA (n=37) 0.46D +/ ORA v. 0.68D +/- 0.34* 0.5D cylinder: 78% with ORA v. 33%*

22 Integration with Aberrometry Woodcock JCRS 2016: prospective, toric IOL Both eyes of 121 patients, randomized worse cataract to ORA v. ink marking + standard calculations 89.2% with MRx cyl 1 month with ORA v. 76.6% without* Mean cylinder 0. 29D v. 0.36D*

23 Benefits of Markerless Systems Time/workflow More accurate Reduces stackable error Less time spent on intraoperative aberrometry Verifying IOL position after viscoelastic removal Helps with small pupil cases Multifocal IOL centration

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25 Benefits of Markerless Systems Time/workflow More accurate Reduces stackable error Less time spent on intraoperative aberrometry Verifying IOL position after viscoelastic removal Helps with small pupil cases Multifocal IOL centration

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27 Biometry and keratometry Manual data transfer from office to OR Pre-op marking 180 axis Surgical marking of target axis Toric IOL alignment 1. Head tilt with topography/keratometry 2. Data transfer (office O.R.) 3. Mark patient (sitting up, need level marks) 4. Identify axis in the O.R. (cyclotorsion, degree gauge)

28 The Critical Window Inoue (Ophthalmology 2017) 72 Tecnis toric eyes at the end of surgery then POH1, POD1, POM1, and POY1 Most rotation happened in the first hour after surgery, rotation of 4.1 degrees Between POH1 and POY1, rotation 0.7 degrees

29 Our Study All toric IOLs April 2015 September 2016 Only included eyes with Callisto Retrospective study, surgeon chose Alcon versus Tecnis toric; CTR used at surgeon s discretion Primary outcome: % >5 or >10 degrees rotation at first post-op visit

30 Study Population Toric Acrysof Tecnis T3/ZCT (48.3%) 331 (51.1%) T4/ZCT (26.3%) 184 (28.4%) T5/ZCT (14.7%) 93 (14.4%) T6 T9/ZCT (10.7%) 39 (6.0%) Total

31 IOL Variable N Mean 95% CI K Cylinder * TECNIS MRx Cylinder IOL rotation abs * K Cylinder * ACRYSOF MRx Cylinder IOL rotation abs *

32 Rotation Acrysof Tecnis > % 97.8% 98.6% 98.9% 99.5% 0.50% 81.8% 93.2% 96.4% 97.4% 99.4% 0.60%

33 Strong tendency for Tecnis to rotate CCW Alcon more CW for WTR

34 Refractive Cylinder % Acrysof % Tecnis <= BCDVA % Acrysof % Tecnis 20/ / / / / /

35 Stepwise Regression Analysis Rotation >5 degrees: No effect of age, sex, AC depth, WTW, Ks, intended axis of correction IOL spherical power was significant Rotation >10 degrees: Surgical axis (worse for WTR) Axial length

36 Repositioning Rate Return to the OR because of rotated IOL: Acrysof 1.6% Tecnis 3.1% (p=0.10) Axial length the only significant predictor on stepwise multiple regression analysis

37 Post-operative Position Various apps available, e.g. toricam, EyeToric, Toraxis, Axis Assistance, etc. Can use a free app such as ihandy Level

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39 (Berdahl & Hardten)

40 Nomenclature Monofocal Pseudoaccommodating Multifocal