Bilateral optic nerve sheath enhancement from giant cell arteritis.

An 83-year-old man presented with acute bilateral visual loss to no light perception (NLP) OD and 20/50 OS. His fundus examination showed moderate bilateral pallid disc edema. A sedimentation rate was 60 mm/h. Magnetic resonance imaging of the brain and orbits with gadolinium revealed marked bilateral enhancement of the optic nerve sheaths and adjacent orbital fat. He underwent biopsies of the optic sheath OD and bilateral temporal arteries. Histopathology of the optic nerve sheath area revealed fibroadipose tissue containing numerous arteries with intimal thickening, and mild mural inflammation consisting predominantly of lymphocyte with occasional giant cells. The bilateral temporal artery biopsies revealed focal disruption of the elastic lamina with rare giant cells. His vision had since stabilized on IV methypdnisolone therapy. The biopsies of the nerve sheath suggest that the radiologic finding of optic nerve sheath enhancement in giant cell arteritis is caused by tbe same pathophysiology, and therefore may be a manifestation of this systemic disease.