Pathological laughter in a patient with Rathke cleft cyst.

Rathke cleft cysts (RCCs) arise from embryonic remnants of Rathke's pouch, and usually manifest as headaches, visual impairments and endocrine disturbances. We report a rare case of suprasellar RCC with the main symptom of pathological laughter. A 14-year-old girl presented with involuntary laughter, ataxia in the right arm and slightly impaired speech articulation. MRI revealed a huge suprasellar cyst causing severe compression of the midbrain and pons. The cyst was removed via a sphenoid ridge keyhole approach. Histologic examination resulted in a diagnosis of RCC. The spontaneous laughing spells disappeared immediately after surgery. In this case, compression of the upper brainstem might have been the cause of the pathological laughter.