Neurosarcoidosis presenting as an isolated mass of the quadrigeminal plate.

A rare case of neurosarcoidosis presenting as an isolated quadrigeminal plate mass without systemic manifestation of this disease is reported. This 26-year-old man presented with symptoms of acute intracranial hypertension including headache, morning vomiting as well as a right homonymous hemianopsia. Magnetic resonance imaging (MRI) showed an expansive tectal mass causing hydrocephalus secondary to an aqueductal obstruction. An external ventricular drainage was inserted and the mass, postulated to be a glioma, was removed through an occipital transtentorial craniotomy. Histopathological examination revealed numerous sarcoid granulomas. Postoperative course was relevant for bilateral hypoacusis and tinnitus, blurred vision, bilateral palpebral ptosis and bilateral internuclear ophthalmoplegia. Chest X-ray was normal. Postoperative thoracic computed tomography (CT) scan showed mediastinal adenopathies. Lung function tests were normal. Angiotensin converting enzyme (ACE) cerebrospinal fluid (CSF) blood ratio was normal. Postoperative treatment and follow-up included corticosteroids, serial lung function tests and cerebral MRI. Neurosarcoidosis may present with protean clinical manifestations and unusual radiological features. This rare diagnosis has to be kept in mind when facing isolated intracerebral mass lesions.