Ischemic papilledema in giant-cell arteritis. Mucopolysaccharide deposition with normal intraocular pressure.

A 68-year-old man died 18 days after the onset of ischemic optic neuropathy caused by histologically proven giant-cell arteritis. On histopathologic study of the eye, ischemic necrosis of the prelaminar and retrolaminar optic nerve was seen, along with the massive presence of acid mucopolysaccharides sensitive to testicular hyaluronidase. This finding was interpreted as an intrusion of vitreal material resulting from breaks in the internal limiting membrane and the pressure gradient from intraocular to extraocular tissues, an analogy to Schnabel degeneration in acute glaucoma.