Double Vision: Isolated Third Cranial Nerve Palsy After Cardiac Catheterization

Neurological complications after cardiac catheterization are rare. We report an unusual case of isolated third cranial nerve palsy in a 72-year-old male patient whose past medical history was significant for diabetes mellitus and coronary artery disease (CAD). He presented for elective cardiac catheterization for stable angina, which revealed multivessel CAD and no intervention was done. Two hours after the procedure, the patient suddenly started complaining of new-onset double vision in his left eye. Ophthalmologic exam revealed ptosis of the left eye lid, sluggish pupillary reflex and impaired adduction of the left eye along with exotropia of the left eye on primary gaze, all findings consistent with the left third nerve palsy. Rest of the neurological exam and neuroimaging (CT angiogram of head and MRI brain) were normal. Embolic phenomenon has been described as a possible mechanism in such patients leading to small vessel ischemic disease and cerebral microinfarction. Neuro-ophthalmologic complications after cardiac catheterization are rare but devastating for the patients. These should be recognized promptly, and patients should undergo neuroimaging to evaluate for any identifiable causes. These patients should be treated with aspirin and statin therapy and evaluated by ophthalmology for correction with prism lenses if symptoms persist.