Posters

How large is just large enough

Poster Details

First Author: S. Bhattacharjee INDIA

Co Author(s):                        

Abstract Details

Purpose:

To determine the minimum size of expanded pupil a pupil expansion device needs to provide for safe and effective phacoemulsification and IOL implantation, irrespective of size or cause of non-dilating pupil, size of the eye or hardness of the cataract.

Setting:

Nayan Eye Centre, Kolkata, India.

Methods:

178 eyes, preoperative pupils 6 mm or less, underwent pupil expansion and phacoemulsification using 6.5 and 7.0 mm square and 6.0, 6.5 and 7.0 mm hexagon Bhattacharjee pupil expansion ring using a horizontal WTW based nomogram. The device is disposed in a 0.1 mm plane, notches engage pupil margin and alternate flanges are placed above and below pupillary margin. Preoperative horizontal WTW, pupil size, cataract hardness and ECD were recorded. Intraoperative incision size, insertion, removal, pupil size, capsulorhexis size, stability, ease of instrumentation, Pupil shape on removal & complications evaluated. Postoperative ECD, pupil size and sphincter tears were recorded.

Results:

When horizontal WTW was 10 mm or less, 6 and 6.5 mm devices used. 6.5 mm hexagon provided a 5.5 mm pupil and was easiest to handle across all sizes of preoperative pupils and eyes. 5.0 mm capsulorhexis provided adequate capsular overlap of IOL and was also safe for all hardness of cataract. In hard cataracts the nucleus was chopped into multiple small fragments to avoid any stress on the capsule and zonules. Expanded pupil more than 5.5 mm caused sphincter tears and provided no additional ease or safety of phacoemulsification or reduction in endothelial cell loss.

Conclusions:

A 5.5 mm pupil provided by a pupil expansion device is good enough for safe an effective phacoemulsification. A larger pupil is unnecessary and could cause pupil sphincter tears. A larger pupil requires a larger device which is unwieldy in small eyes which are often associated with shallow anterior chambers. In this series, the B-HEX 6.5 device consistently provided a hexagonal pupil measuring 5.5 mm from side to side permitting a 5.0 mm capsulorhexis. With present day phaco technology and techniques, prevention of collapse of the pupil is more important than expansion of pupil provided by a device.

Financial Disclosure:

One or more of the authors gains financially from product or procedure presented