Methylene blue associated retinal toxicity

Background To describe a case of inadvertent methylene blue use during pars plana vitrectomy (PPV) for an epiretinal membrane (ERM). Case A 69-year-old man presented with 1 day of severe vision loss in his left eye. Two days prior to presentation, he had undergone PPV that was complicated by accidental methylene blue use. Visual acuity (VA) at presentation to our institution was CF from his baseline VA of 20/60. Optical coherence tomography (OCT) demonstrated diffuse hyperreflectivity and thickening of the inner retinal layers. The patient was started on oral prednisone with no improvement. On postoperative month 1, VA was HM. OCT showed disruption of the inner retinal architecture, inner retinal layer thinning and focal disruption of the outer retina layers superiorly. Conclusion Methylene blue may be associated with severe retinal toxicity. Given its similarity to other vital dyes in ophthalmology, care must be taken to avoid its inadvertent administration.