Calcifying Pseudoneoplasm of the Neuraxis (CAPNON) of the Anterior Skull Base: Report of a Case

Calcifying pseudoneoplasms of the neuraxis (CAPNON) are rare, benign, fibro-osseous lesions of the central nervous system. They can occur anywhere in the central nervous system, and arise with roughly equal frequency in the spine and brain parenchyma. The etiology of these lesions is uncertain, but they are thought to arise from a reactive as opposed to a neoplastic process. Treatment of these lesions is typically with surgical excision. Herein, we report a case arising in a 19-year-old man presenting with chronic headache, unilateral rhinorrhea, and epiphora. The lesion was located along the anterior skull base, with sinonasal and orbital extension. The lesion was resected using an endoscopic, transethmoidal approach.