Impact of intraocular lens design and implantation of a capsular tension ring on capsular bag stability assessed with a dynamic Purkinje meter system

Session Details

Session Title: Cataract Surgery Outcomes / Femto

Session Date/Time: Monday 15/09/2014 | 08:00-10:30

Paper Time: 08:00

Venue: Auditorium

First Author: : S.Maedel AUSTRIA

Co Author(s): :    N. Hirnschall   M. Weber   J. Tabernero   P. Artal   O. Findl  

Abstract Details

Purpose:

To compare capsular bag stability using a dynamic Purkinje meter system in eyes with implantation of single-piece vs. three-piece intra ocular lenses (IOLs), plate haptics vs. open-loop haptic IOL and with and without implantation of a capsular tension ring (CTR) during cataract surgery.

Setting:

Vienna Institute for Research in Ocular Surgery, Department of Ophthalmology, Hanusch Hospital, Vienna.

Methods:

Different IOL and haptics design as well as the implantation of a CTR during cataract surgery may improve intracapsular IOL stability and reduce decentration and tilt. A recently described dynamic Purkinje meter system allows measurement of the dangling or “wobbling” of an IOL by analyzing saccadic eye movements with simultaneous video recording of Purkinje reflexes. Lens or IOL wobbling can be quantified by terms of maximal wobbling amplitude (pixels) or maximal wobble time (msec). Higher oscillation amplitudes and larger wobble time indicate a larger amount of lens/IOL wobbling. In this prospective, randomized clinical trial, 120 eyes of 60 patients were included in 3 subgroups, in which a bilateral comparison of IOL stability was performed (subgroup 1: 1-piece vs. 3-piece IOL; subgroup 2: plate haptics vs. open-loop haptics IOL; subgroup 3: with CTR vs. without CTR). IOL tilt, decentration and wobbling parameters were measured in all eyes pre-operatively, 1 hour, 1 week and 3 months post-operatively.

Results:

Preliminary results include data of 28 eyes of 14 patients in subgroup 1 and 36 eyes of 18 patients in subgroup 3. At all time points, mean wobble parameters were slightly smaller in eyes with a 1-piece IOL compared to eyes with a 3-piece IOL. At 1 hour, 1 week and 3 months post-OP, mean (SD) wobble amplitude for 1-piece and 3-piece IOLs was 34.2 pixel (20.2), 41.7 (22.0), 37.2 (18.4) and 38.0 pixel (20.2), 47.1 (18.1), 44.9 (16.3), respectively. Mean (SD) wobble time for 1-piece and 3-piece IOLs was 99.5 msec (40.1), 112.0 (43.2), 95.0 (35.9) and 139.2 msec (58.9), 157.8 (69.4), 126.4 (46.0), respectively (p>0.05) Mean wobble amplitude for eyes with/ without a CTR were 36.17 pixel (15.3), 35.6 (19.8) and 27.0 (15.2) and 35.9 (16.9), 50.7 (22.6), 31.0 (21.7), respectively. Mean wobble time for eyes with CTR and eyes without CTR was 105.0 msec (37.2), 94.1 (29.9), 100.7 (24.2) and 109 (33.6), 130.6 (35.3), 116.2 (34.7), respectively. 1 week post-OP, wobble parameters were significantly lower (p=0.04; p=0.02) in CTR eyes than in the eyes without CTR. Mean IOL tilt and decentration were low and did not differ between eyes in both groups at any time point (p>0.05).

Conclusions:

Whereas static IOL in-the-bag-stability parameters did not differ between different IOL designs or with/ without implantation of an CTR, dynamic parameters revealed some differences between the treatment groups: In subgroup 1, single-piece IOLs showed minimally, but not statistically significantly, higher capsule bag stability compared to 3-piece IOLs (p>0.05). Additionally, a significant lower wobble effect was detected in eyes after implantation of a CTR compared to eyes without implantation of a CTR 1 week post-OP. However, analysis of the complete dataset should be awaited to draw final conclusions. Additionally, data of subgroup 2, comparing capsule bag stability of IOLs with plate haptics and IOLs with open-loop-haptics will be presented.

Financial Interest:

NONE