Abstract
Purpose :
The axial length (AL) becomes shorter as intraocular pressure (IOP) decreases after
trabeculectomy. We hypothesized that AL changes in response to decreased IOP after trabeculectomy could be different between primary open-angle glaucoma (POAG) and pseudoexfoliative glaucoma (XFG) due to the different properties of connective tissue and ECM in the sclera. Aim of this study is to investigate whether changes in axial length (AL) after trabeculectomy differ depending on type of glaucoma.
Methods :
This retrospective, consecutive study included 38 phakic eyes with POAG, and 21 phakic eyes with XFG. All patients underwent baseline evaluation with Goldmann applanation tonometer, automated keratometer and laser interferometer before trabeculectomy. Postoperative evaluation was performed when subsequent cataract surgery was planned. Eyes that did not achieve complete success after trabeculectomy were excluded. Changes in (△) IOP, keratometric value (Kv), anterior chamber depth (ACD), and AL were compared within and between the groups. We also investigated the factors associated with the amount of AL reduction using logistic regression analysis.
Results :
The mean IOP and AL was reduced by 9.2 mmHg and 0.14 mm in POAG, and 10.8 mmHg and 0.07 mm in XFG eyes after trabeculectomy. Although amount of IOP reduction after trabeculectomy was not different (p = 0.385), the AL decreased significantly in eyes with POAG (p <0.001), but not in XFG (p = 0.088). The △ AL were different between two groups (p = 0.008). The △ ACD and △ Kv were not significantly different between two groups. The linear regression analysis showed that preoperative IOP affected on △ AL in POAG (R2 = 0.232, p = 0.001), but not in XFG (R2 = 0.004, p = 0.347). The △ AL were correlated with the type of glaucoma (POAG/XFG; OR = 17.473, p = 0.008), and △ IOP (OR = 1.324, p = 0.009) by multivariate logistic regression analysis.
Conclusions :
AL reduction after trabeculectomy was smaller and less predictable in XFG than in POAG. When planning the combined trabeculectomy and cataract surgery, different AL responses depending on the type of glaucoma should be considered for optimal intraocular lens power calculation.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.