[Evaluation of trypan-blue toxicity in macular hole surgery with electroretinography].

PURPOSE Concern has been raised about the retinal toxicity of vital dyes. We designed a prospective study to determine the possible toxicity of trypan-blue (TB) in macular hole surgery with TB-assisted internal limiting membrane (ILM) peeling through the performance of electroretinograms (ERGs). METHODS Patients diagnosed with a macular hole underwent ophthalmological evaluation prior to surgery and at 6 months follow-up. All patients underwent vitrectomy and ILM-staining under air. All phakic patients underwent phacoemulsification and IOL implantation simultaneously. There were two study groups: In group 1, ILM-staining was performed with 0.06% TB, while in group 2 the procedure was performed with 0.15% TB. Preoperative ERG recordings were measured in the week prior to surgery. Postoperative ERGs were measured 3 to 6 months after surgery. The ERG data between eyes with macular hole and fellow eyes were compared in the pre- and post-operative stages. Visual acuity (VA) changes in both groups were evaluated. RESULTS Nine patients were recruited in each group. VA improved significantly in both groups, with more than 65% of patients improving more than 2 lines. There were no statistical differences in VA gain between groups or in ERG values between affected and fellow eyes. CONCLUSION No significant retinal toxicity of TB staining could be clinically detected.