Posters

Refractive lens exchange: changes in intraocular pressure (IOP) with respect to ametropia, axial length, anterior chamber depth and white-to-white diameter

Poster Details

First Author: M. Wevill UNITED KINGDOM

Co Author(s):    J. Dermott   C. O'Donnell   A. Hartwig              

Abstract Details

Purpose:

To determine if postoperative IOP changes were related to preoperative ametropia, anterior chamber depth, axial length or white-to-white measurements in eyes with clear lenses undergoing refractive lens exchange.

Setting:

Optegra Eye Hospitals, United Kingdom.

Methods:

A retrospective review of 1947 eyes of 1391 patients undergoing refractive lens exchange in patients with clear lenses was done. All patients had a preoperative corrected distance visual acuity (CDVA) of LogMAR 0.04 or better. Mean age was 60±8 years. Change in IOP was analysed according to preoperative ametropia and biometry data. Changes in IOP were assessed according whether eyes were emmetropic, or had low, moderate or high myopia or hyperopia. Change in IOP was also analysed according to anterior chamber depth, axial length and white-to-white values. The mean follow up was 220 days.

Results:

Mean IOP decreased from 16.1±3.4 mmHg preoperatively to 14.7±3.4 mmHg postoperatively. Mean decrease in IOP was 1.3±3.3 mmHg. All groups had a mean decrease in IOP. The largest proportion of eyes showing a decrease in IOP occurred in eyes with high hyperopia (76.1%, pre-op spherical equivalent >+6.00D) and the smallest proportion of eyes showing a decrease in IOP had high myopia (53.8%, preoperative spherical equivalent <-6.00D). Decreased IOP was most common in eyes with shallow anterior chambers (anterior chamber depth 2.51-2.80mm, 68% incidence), shorter axial lengths (21.01-22.00mm, 69% incidence) and larger white-to-white diameters (13.01-13.50mm, 66% incidence).

Conclusions:

Previous studies have demonstrated a decrease in IOP in patients undergoing cataract surgery. This study shows a mean decrease in IOP in eyes after refractive lens exchange in eye with clear lenses. A decrease in IOP was more common in eyes with higher hyperopia, larger white-to-white diameters, shallower anterior chamber depths and shorter axial lengths. Many factors including diurnal variation affect IOP measurements. These factors were not controlled in this retrospective record review. Therefore further study of these observations is necessary.

Financial Disclosure:

NONE