A rare case of symptomatic Rathke's cleft cyst in a 26-year-old female is reported. The clinical and radiological features of this lesion are described with emphasis on the differential diagnosis between Rathke's cleft cyst and craniopharyngioma.Rathke's cleft cysts present a common incidental intrasellar autopsy finding occurring in 13% to 22% of randomly examined pituitary glands [1]. These lesions rarely, however, enlarge sufficiently enough to cause compression of adjacent neural structures. Although to date, approximately 155 cases of symptomatic Rathke's cleft cysts have been reported in the pertinent literature [2]; the condition continues to be largely unknown to clinicians.The purpose of this case report is to draw attention to this pathological entity which should be considered in the differential diagnosis of cystic lesions in the sellar area. To the best of our knowledge, this is the first case of symptomatic Rathke's cleft cyst to be reported from Saudi Arabia. Case ReportThis 26-year-old Filipino female dietitian presented to the Neurosurgical Division of the King Khalid University Hospital with a two month history of constant headaches which were associated with nausea and nonprojectile vomiting. There were no visual disturbances and apart from oligomenorrhea since puberty, her past medical history was unremarkable. ExaminationThe patient was short in stature (height 140 cm and weighed 37.5 kg). Skin and hair distribution were normal. Neurological status of the patient was normal except for a bi-temporal hemianopia.The plain x-ray of the skull revealed erosion of the dorsum sellae with no sellar abnormality. Cranial computerized tomographic (CT) scan showed a large low density lesion measuring 30×39 mm with faint ring enhancement filling the entire suprasellar space with compression of the third ventricle (Figure 1). The magnetic resonance imaging (MRI) demonstrated the lesion extending into the sella and elevating the floor of the third ventricle. The lesion was hyperintense on both T1 and T2 weighted images except for a small nidus which could have represented a solid component of the lesion. The vertebral angiography disclosed marked dorsal displacement of the distal end of the basilar artery.The basal secretion of the following hormones was normal: T3, T4, TSH, Cortisol, prolactin, LH, FSH, and growth hormone. The pituitary dynamic tests after injection of insulin, TRH, and GnRH revealed inadequate GH and FSH responses. OperationThe patient underwent a right frontotemporal craniotomy. A thin-walled, brown-greenish cyst was encountered. The right optic nerve was stretched over the cyst wall and the right carotid artery was displaced laterally. The cyst was punctured and 35 cc of milky greenish fluid was aspirated. The inferior part of the cyst wall was excised leaving the superior part, which was firmly attached to the floor of the third ventricle, unremoved. Postoperative CourseThe patient recovered well but developed transient diabetes insipidus which was controlled with vasopressin. Two year...