Contralateral amaurosis after a retrobulbar block

PURPOSE: To describe and discuss the workup and management of a rare complication of retrobulbar anesthesia, as well as CT and MRI findings of this complication. OBSERVATIONS: The patient underwent uncomplicated pars plana vitrectomy with membrane peel for epiretinal membrane removal. Shortly after completion of surgery, the patient noted that he could not see out of his non-operated eye. Visual acuity was bare hand motion, and physical exam revealed a dilated, non-reactive pupil with normal, well-perfused retina. Imaging revealed an air bubble in the optic nerve of the operated eye, suggesting penetration of the optic nerve sheath during retrobulbar block with posterior spread of anesthetic to the contralateral optic nerve. CONCLUSIONS AND IMPORTANCE: After imaging ruled out acute intracranial pathology and confirmed the correct diagnosis, the patient was monitored until vision in the non-operated eye returned to baseline. Excellent visual acuity was attained in the operated eye. Central spread of anesthetic after retrobulbar anesthesia is a rare but potentially life-threatening complication that must be promptly diagnosed and addressed.