Abstract
Purpose :
While studies have examined structural differences in the optic nerves of primary-open angle glaucoma (POAG) patients with asymmetric central corneal thickness (CCT), few have explored whether a difference in outcomes exist between the eyes of these patients. Our study attempts to evaluate whether there is a difference in progression to surgery in the eyes of primary open-angle glaucoma patients with asymmetric CCT.
Methods :
This is a retrospective cohort study that included all POAG patients who underwent trabeculectomy or seton tube placement at an inner city hospital between 1/1/13–5/25/15. Patients were identified with CCT asymmetry of greater than 10μm (>10μm group) and were compared to those with a 10μm difference or less (≤10μm group). Exclusion criteria included any corneal pathology or surgery that could affect CCT. CCT measurements were obtained via an ultrasound-based pachymeter. Nominal data was analyzed using a 1-tailed chi square test while continuous data was analyzed by unpaired t-test.
Results :
40 patients (21 in the >10μm group, 19 in the ≤10μm group) met the inclusion criteria. The average age was 69.3±10.7 years with 43% men in the >10μm group, and 65.2±14.5 years (p=0.75) and 57% males (p=0.52) in the ≤10μm group. 62% (13 of 21) of patients underwent trabeculectomy in the >10μm group while 79% (15 of 19) underwent trabeculectomy in the ≤10μm group (p=0.12). In the >10μm group, the mean difference in CCT between eyes was 30.1±20.0μm, while it was 4.60±3.00μm in the ≤10μm group (p<0.01). In the group with >10μm difference, the eye with the thinner CCT underwent first surgical intervention in 81% (17 of 21) of patients, compared to 47% (9 of 19)(p=0.01) in the ≤10μm group.
Conclusions :
Our results show that in POAG patients with CCT difference of >10μm, the side with the thinner CCT has a higher risk of progression to surgery first. This study may further suggest that physicians should be vigilant in obtaining CCT measurements in all glaucoma patients, with careful clinical monitoring of the eye with thinner CCT for progression.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.