[Rathke's cleft cyst].

Rathke's cleft cyst (RCC) are frequent benign cystic sellar lesions. Most RCC are small, intrasellar and asymptomatic. Larger cysts may compress adjacent structures and rarely become symptomatic. Diagnosis is strongly suggested at MRI by the presence of a midline non-enhancing lesion located exactly between the anterior and posterior lobes of the pituitary gland. Even if its signal is variable and related to intracystic protein concentration, it must be homogeneous with no fluid-fluid level. Once a diagnosis of RCC made, routine MR and clinical follow-up is sufficient for incidental asymptomatic cysts whereas the rare symptomatic lesions are neurosurgically resected.