Commentary: Cataract versus combined surgery in pseudoexfoliation glaucoma

Field: Medicine (Health Sciences)

Glaucoma associated with exfoliation syndrome is particularly difficult to manage. It tends to be more aggressive and have a poorer prognosis than other open-angle glaucomas.[1] The reasons for this may be associated with higher intraocular pressures (IOPs), greater diurnal and inter-visit IOP fluctuations, and greater vulnerability of the optic nerve to damage. In a small number of cases, pseudoexfoliation glaucoma may have angle-closure mechanism.[2] These patients require YAG peripheral iridotomy (PI). However, pseudoexfoliation glaucoma with open angles may present with acute IOP rise that mimics acute angle closure.[3] Visually significant cataract that requires surgery is often seen in these patients but the probability of complications include a higher-than-average risk of zonular dehiscence or capsular breaks,[4] due most likely to degeneration of zonular fibrils[5] or thinner posterior capsule,[6] poor pupillary dilatation and synechiae between iris pigment epithelium and the peripheral anterior lens capsule,[7] and compromised endothelial status. Presence of YAG PI increases the chances of zonular dehiscence too. Postoperatively, eyes with pseudoexfoliation are more likely to experience more inflammation than others. Though the standard rule of going for only phacoemulsification in patients who are well controlled with a single medication usage and have an IOP within the target range with mild-to-moderate visual field damage and disc changes applies to patients of pseudoexfoliation too, the rationale for a combined procedure—as opposed to cataract surgery alone in an eye with good IOP control but moderate-to-advanced damage—is the risk of increased IOP in the early postoperative period. Studies indicate that such postoperative raised IOPs are significantly less after combined surgeries than after phacoemulsification alone.[8] Thus higher rates of intraoperative complications with vitreous loss in pseudoexfoliation glaucoma eyes may be a deterrent for choosing combined surgeries in these eyes. Considering the multiple risk factors associated with surgery in pseudoexfoliation eyes, the present study under discussion provides helpful insights. The authors of the study did not find any significant difference in the level of IOP reduction or complication rates for eyes undergoing cataract or combined surgery in patients with pseudoexfoliation. The authors reported postoperative transient inflammatory IOP spike as the most common early complication found in this study, which is consistent with our experience. While combined surgeries had higher transient and late complication rates, the IOP and visual acuity outcomes were similar in both groups in this study. In spite of combined surgeries having higher transient and late complication rates, the IOP and visual acuity outcomes were similar with only the cataract surgery group in this study. No study has exclusively compared pseudoexfoliation glaucoma patients with regards to combined surgery and cataract surgery alone. The results of this study—though a retrospective one and a single surgeon cases series—is worth considering while we make our decision on whether cataract surgery alone as opposed to combined surgery can be as effective in pseudoexfoliation glaucoma eyes.