"Not Right in the Head" - Video

A 55 year old man presented with eight months of progressive left orbital swelling. His past ocular history was significant for LASIK of the right eye with monovision. His past medical history was significant for melanoma of the left arm, treated by surgical excision, with two negative lymph nodes, as well as hypertension, diabetes mellitus, peripheral neuropathy, and peptic ulcer disease. On ophthalmologic examination, visual acuity at distance was 20/15 OD and 20/80 OS, pinholing to 20/25 OS. There was no afferent pupillary defect. Color plates were 15/15 in both eyes. Hertel exophthalmometry measurements were 20 mm OD and 26 mm OS. Motility was full in both eyes. The left upper eyelid was mildly edematous, and there was moderate conjunctival chemosis of the left eye. The remainder of the ophthalmologic examination was normal. He had no systemic symptoms. Per report, outside MRI of the brain showed diffuse orbital involvement on both sides, with no specific mass or infiltrative features. Initial laboratory tests, including HIV serology, c-ANCA, p-ANCA, and ANA, were all negative. A procedure was performed