Abstract
Purpose :
Phacomorphic glaucoma (PG) is a rare but clinically significant acute presentation where emergent cataract surgery is required. Intraocular lens (IOL) calculations can sometimes be challenging in these patients due to corneal edema and hypermature cataracts impairing adequate view. For this reason, we chose to investigate whether expected refractive error based on IOL calculations differed from expected refractive outcome post-surgery.
Methods :
A retrospective analysis of patients presenting with PG between 2009 to 2018 who underwent cataract surgery and had a postoperative refraction were included. Information collected included presenting and postoperative best corrected visual acuity (BCVA), intraocular pressure (IOP) pre and post operatively, and presence of corneal edema. Predicted spherical equivalence (SphEq) data was collected from IOL calculations, and postoperative SphEq was calculated from postoperative manifest refraction.
Results :
Twenty patients with PG who underwent cataract surgery were identified; of these, 10 patients and 10 eyes who underwent manifest refraction postop were included. 70% were female, mean age of presentation was 75.7 ± 11.5 years, and 90% of patients were of African American race. Mean BCVA at presentation was 20/544 (LogMAR 1.44), and mean preop IOP was elevated at 24.6 ± 14.2 mmHg. At the time of IOL calculations, 3 patients had corneal edema, and 2 patients underwent a peripheral iridotomy prior to surgery. Postop, BCVA improved to a mean of 20/192 (LogMAR 0.983). IOP also reduced postoperatively to a mean of 19 ± 8.8 mmHg. The mean difference between the predicted and actual refractive error, as calculated by SphEq was 0.088.
Conclusions :
The study shows an improvement in visual acuity and IOP postcataract surgery in patients with PG, as would be expected. The study also demonstrates that patients ended up with a slightly more myopic refractive error than expected postoperatively. This is a new finding not previously published in literature. One implication for this could be an adjustment to the IOL calculations done preoperatively to account for the hypermature cataract and corneal edema that can potentially limit accurate IOL calculations.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.