Atypical Retinal Hemorrhages after Vitrectomy for Idiopathic Macular Hole: Possible Toxicity of Brilliant Blue G

PURPOSE: To describe the development of multiple retinal hemorrhages after uncomplicated macular hole (MH) surgery, and to determine the associated factors. METHODS: The medical records of 163 patients (167 eyes) diagnosed with idiopathic MHs and who underwent surgery at Pusan National University Hospital between March 2016 and July 2018 were retrospectively reviewed. The development of retinal hemorrhages was evaluated using ultra-widefield fundus photographs. Multiple retinal hemorrhages were defined as three or more dot or blot hemorrhages that had not been observed before and during the surgery. The patients were divided into two groups according to the presence of multiple retinal hemorrhages. The variable parameters were compared between the two groups to find the risk factors. The associated factors were evaluated further for the independent factor using multiple logistic regression analysis. RESULTS: Multiple retinal hemorrhages were observed in 31 eyes (18.6%) after MH surgery. The associated factors were the surgical induction of posterior vitreous detachment (PVD) (p = 0.003), use of the internal limiting membrane flap technique (p = 0.028), and staining with Brilliant Blue G (BBG) (p = 0.003). Retinal hemorrhages were exclusively observed in eyes in which BBG was used. Surgical PVD induction was the only independent risk factor (odds ratio, 13.099; p = 0.013). No statistically significant differences were observed between the two groups in the postoperative visual outcomes and MH closure rate. Additionally, patients who underwent surgery for idiopathic epiretinal membrane during the study period were reviewed to validate the above findings. Multiple retinal hemorrhages were noted in only one case (0.4%) in which BBG was used after surgical induction of PVD. CONCLUSIONS: Multiple retinal hemorrhages after MH surgery appear to be related to the intravitreal use of BBG in eyes that sustained mechanical damage because of surgical induction of PVD; however, they did not affect surgical outcomes.