Meningeal melanocytosis: a challenging diagnosis

A 22-year-old woman with a history of gradually worsening headache, who had developed nausea, vomiting, and diplopia within the past month, was referred to the Department of Neurosurgery of Hospital de Santo António (Porto, Portugal) in June, 2017. Initial neurological examination and cerebrospinal fluid (CSF) studies were unremarkable. Lumbar puncture opening pressure was elevated. The patient had no lesions evoking a congenital phakomatosis or...