Is Cystoid Macular Edema More Frequent In Vitrectomized Internal Limiting Membrane-Peeled Eyes Undergoing Phacoemulsification?

Purpose/Aim of study: We postulate that the timing of phacoemulsification relative to pars plana vitrectomy, internal limiting membrane peel (before, during or after) and gas is an important risk factor for cystoid macular edema.

Materials and Methods: We report a retrospective study of 43 eyes in 43 patients. All patients underwent vitrectomy, internal limiting membrane peeling and gas for full-thickness macular hole. Patients were categorized according to their phakic status prior to vitrectomy. Group 1 remained phakic through the 12-month study and acted as a control group, group 2 had combined surgery, group 3 were pseudophakic prior to vitrectomy and group 4 became pseudophakic subsequent to vitrectomy. Patients with postoperative optical coherence tomography (OCT)-proven CME with at least one cyst within the OCT field associated with increased central macular thickness (CMT) were identified.

Results: CME was noted in 6/43 patients (14%). CME occurred in 38% of group 4 compared to 0% of group 1, 11% of group 2 and 11% of group 3. This difference did not reach statistical significance when rates were compared to group 1 (Anova: group 2: p = 0.853; group 3: p = 0.876; group 4: p = 0.173). The mean (± standard deviation) LogMAR best-corrected mean visual acuity (BCVA) improved from 0.44 (±0.27) at time of CME diagnosis to 0.35 (±0.19), with a mean decrease in CMT from 392.2 (±102.5) µm to 287.7 (±34.0) µm.

Conclusions: We report a trend of higher incidence and recurrence of CME in vitrectomized ILM-peeled eyes undergoing phacoemulsification than in other sequences of these procedures.