Optic neuropathy caused by naso-orbital mass in chronic intranasal cocaine abuse.

: A 48-year-old woman with a history of chronic intranasal cocaine abuse presented with unilateral proptosis associated with severe visual loss from optic neuropathy in the right eye. Imaging showed extensive bone and soft tissue destruction in the paranasal region and an orbital mass. Initial biopsies suggested a low-grade neoplasm. The correct diagnosis was established only on repeat biopsy, which revealed marked pleomorphism and nonspecific chronic inflammation with irregular collagen bundles containing thick-walled blood vessels. This case emphasizes that intranasal cocaine abuse may clinically, radiographically, and histopathologically mimic a neoplasm or a necrotizing vasculitis.