Radiological Characteristics in Rathke's Cleft Cyst.

Rhee, Jong Joo; Kim, Jeong Hoon; Kim, Chang Jin; Lee, Jung Kyo; Jung, Hee Won

Original Article

Journal of Korean Neurosurgical Society 2003;34(2): 140-145.

Jong Joo Rhee, Jeong Hoon Kim, Chang Jin Kim, Jung Kyo Lee, Hee Won Jung

¹Department of Neurosurgery, Konyang University College of Medicine, Konyang University Hospital, Daejeon, Korea. medpia@kyuh.co.kr
²Department of Neurosurgery, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Korea.
³Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Korea.

ABSTRACT

OBJECTIVE
The study is conducted to define the preoperative radiological findings of Rathke's cleft cysts (RCCs) differentiating these lesions from other sellar/parasellar cystic tumors. METHODS: A retrospective study of 65 patients with RCC patients from two institutes (53 cases / 12 cases) was performed. All patients had preoperative magentic resonance imaging(MRI) studies, and computed tomography(CT) studies were available in 25 patients.
RESULTS
Calcification detectable on CT scanning was present in only 8% of RCC patients. Of the patients who were available for precontrast CT images, 48% had cysts of low attenuation, 28% had cysts of the same attenuation, and 24% had cysts of increased attenuation relative to the brain. Of the patients who had postcontrast CT images, 84% showed no significant change following contrast agent administration, and 16% demonstrated rim enhancement. MR imaging revealed multiple patterns. In T1-weighted sequences, 55.4% showed hyperintense signals, 27.7% showed hypointense signals, 12.3% showed isointense signals, and we saw a mixed-intense signal in 4.6%. In T2-weighed images, we observed a hyperintense signal in 60%, a hypointense signal in 20%, a mixed-intense signal in 13.8%, and an isointense signal in the remaining 6.2%. In Gd-DTPA enhanced images, 72.3% of the 65 patients showed no enhancement either of the cyst contents or of the cyst wall, and 27.7% demonstrated rim enhancement. Forty-five of the 65 patients were preoperatively diagnosed as RCCs.
CONCLUSION
RCCs show variable CT and MRI characteristics. There is no unique finding for this pathology. Thus, even with CT and MRI studies, differential diagnosis with other cystic lesions of the sellar/parasellar region remains difficult.