Fundus autofluorescence after vitrectomy with ILM peeling and subfoveal injection in diabetic macular edema

Purpose To determine whether subretinal injections cause defects in the RPE that are visible on fundus autofluorescence (FAF).Methods This retrospective study analyzed twenty-six eyes after vitrectomy with ILM peeling and subretinal injection of balanced salt solution for diabetic macular edema (DME). FAF was performed before and 36 months after surgery. Four FAF patterns were distinguished: grade 1 -normal autofluorescence, grade 2 -one or more hyperautofluorescent spots, grade 3 -central increased autofluorescence, grade 4 -central decreased autofluorescence.Results Visual acuity improved from 0.18 to 0.26 Snellen (p = 0.03). Retinal thickness decreased (p = 0.01). The injection site would not be possible to spot on postoperative FAF without reviewing surgical videos. Grade 1 pattern was visible in 31% operated and 36% fellow eyes, Grade 2 pattern was observed in 11% operated and in 43% fellow eyes, Grade 3 pattern in 31% operated and in 14% fellow eyes and grade 4 pattern in 31% operated and in 14% fellow eyes.Conclusion No abnormal FAF patterns were observed at the subretinal injection sites. ILM peeling likely decreases the pressure required to perform the injection and protects the RPE from iatrogenic damage. Anomalous autofluorescence patterns are most likely associated with long-standing disease.