RISK FACTORS AND PREDICTIVE CUTOFF VALUES FOR NEW-ONSET MICROSCOTOMA AFTER VITRECTOMY WITH INTERNAL LIMITING MEMBRANE PEELING FOR EPIRETINAL MEMBRANE.

PURPOSE: To identify the risk factors and predictive cutoff values for new-onset microscotoma after vitrectomy with internal limiting membrane peeling for epiretinal membrane.

METHODS

This retrospective study included patients who underwent vitrectomy with epiretinal membrane and internal limiting membrane peeling. Visual acuity, metamorphopsia, and visual field (Humphrey Field Analyzer 10-2 program) were evaluated preoperatively and at 3 to 6 months and 12 months postoperatively. New-onset microscotoma was defined as any test points decreasing from ≥10 dB preoperatively to <10 dB at 3 months to 6 months. Risk factors, vulnerable regions, and preoperative threshold cutoff values for new-onset microscotoma were analyzed.

RESULTS

New-onset microscotoma was observed in 31 (17.8%) of 174 eyes (174 patients; 67.7 ± 8.2 years). Visual acuity and metamorphopsia improved significantly at 12 months postoperatively (both P < 0.0001). A multivariate analysis identified glaucoma (odds ratio = 8.18), secondary epiretinal membrane (odds ratio = 4.45), indocyanine green usage (odds ratio = 3.70), and male sex (odds ratio = 2.46) as significant risk factors. Vulnerable regions corresponded to the temporal and inferior macula ( P < 0.01). The overall preoperative threshold cutoff value was 27.5 dB (area under the curve = 0.85, P < 0.001), whereas in eyes with glaucoma (n = 18), it was 26.5 dB (area under the curve = 0.90, P < 0.001). Both analyses demonstrated a negative predictive value exceeding 99%.

CONCLUSION

The identified risk factors, vulnerable regions, and cutoff values may guide preoperative patient counseling and development of safe strategies to prevent postoperative microscotoma. The high negative predictive values highlight reliable identification of low-risk areas, contributing to internal limiting membrane peeling approach optimization.