A Boy with Rathke's Cleft Cyst

We report a 13-year-old boy with Rathke's cleft cyst who had diabetes insipidus (DI), visual disturbance, and GH deficiency. He was admitted to our hospital in 1988 because of polyuria and visual disturbance. He had homonymous hemianopsia and DI; however, the brain computed tomography (CT) was normal. He received 1-deamino-8-D-arginine vasopressin (DDAVP) therapy. In 1989, he was found to have GH deficiency and GH treatment was started. In 1991, a 1.2 cm sized mass was found in the sella area by magnetic resonance imaging (MRI) and removed by microscopic transsphenoidal surgery. Histological examination revealed a Rathke's cleft cyst with craniopharyngioma. In spite of visual disturbance at the first visit, no mass had been found in the brain by CT or MRI during the first two years of GH treatment. However, the mixed form of Rathke's cleft cyst and craniopharyngioma had grown rapidly and was subsequently detected by MRI. He has to be followed up very carefully by MRI for a long period.