Endoscope-assisted biopsy for the diagnosis of neurosarcoidosis

A 56-year-old woman was followed in the neurological department for febrile mental confusion. The diagnosis of sarcoidosis was suggested on the ground of associated abdominal lymphadenopathy, elevated serum angiotensin-converting enzyme level, aseptic meningitis and intracranial hypothalamic lesion. Nevertheless, radiological, biological and histological analyses could not assert the diagnosis of systemic sarcoidosis. Six months later, cerebral MRI showed a recent enhanced nodule, located near the right choroid plexus, inducing a dilatation of the right temporal ventricular horn. A surgical endoscope-assisted biopsy of that lesion was decided. The endoscope was introduced in the right trapped temporal ventricle. The limits between normal and pathological tissues were clearly identified. The biopsy was thus accurately performed. Histological analysis definitely confirmed the diagnosis of neurosarcoidosis. No postoperative complication was noted. We report a case of neurosarcoidosis which was diagnosed by ventricular endoscope-assisted biopsy. The discussion stresses the potential advantages of endoscopy for the diagnosis of small periventricular lesions when ventricular dilatation is associated.