Neuro-ophthalmologic complications of cataract surgery

Neuro-ophthalmologic complications from cataract surgery are uncommon and include central nervous system toxicity, binocular diplopia, traumatic optic neuropathy and ischemic optic neuropathy. Retrobulbar blocks may be accidentally injected into the subarachnoid space with diffusion to the brainstem. This leads to cardiovascular, respiratory, and mental status compromise. Most patients have complete recovery with adequate support. Post-operative, binocular diplopia may occur secondary to anisometropia or previously unrecognized misalignment. Periocular injection may cause paresis or fibrosis of extraocular muscles. Anterior or posterior ischemic optic neuropathy can occur in the first 6 weeks after cataract surgery with or without periocular injection. The risk to the other eye is high with subsequent contralateral cataract extraction. Post-operative vision loss associated with direct traumatic needle injury is recognized immediately. Therefore, an orbital MRI may be warranted for a patient with an optic neuropathy in the first 24 hours after cataract surgery using periocular anesthesia. If evidence of needle injury is present on neuroimaging, a trial of steroids should be considered.