Colloid cysts of the third ventricle: are MR imaging patterns predictive of difficulty with percutaneous treatment?
OBJECTIVE
Colloid cysts of the third ventricle are rare benign brain tumors. The purpose of this study was to correlate their patterns on MR images with the probability of success of percutaneous treatment.


METHODS
Nineteen patients underwent endoscopic treatment for colloid cysts of the third ventricle. The cases were divided into two groups based on difficulty of the aspiration procedure. We reviewed CT scans and MR images and divided cysts into groups based on their signal intensity on the MR images and their density on CT scans. Intensity and density were correlated with difficulty of aspiration during the endoscopic procedure.


RESULTS
The aspiration procedure was difficult in 63% of the cases. Eighty-nine percent of hyperdense cysts on unenhanced axial CT scans were categorized as difficult, and 75% of hypodense cysts were categorized as easy. On T2-weighted MR sequences, 100% of low-signal cyst contents were difficult and nearly 63% of high-signal lesions were easy. There was a significant correlation between the T2-weighted sequences and the CT scans regarding the difficulty of the aspiration procedure.


CONCLUSIONS
T2-weighted MR sequences are useful for predicting difficulty of aspiration during stereotactic or endoscopic procedures. A T2-weighted low-signal cyst is correlated with high-viscosity intracystic contents.
El Khoury
C
C
Department of Neuroradiology, Hôpital Henri Mondor Creteil, France.
Brugières
P
P
Decq
P
P
Cosson-Stanescu
R
R
Combes
C
C
Ricolfi
F
F
Gaston
A
A
D000328:Adult; D000368:Aged; D020863:Central Nervous System Cysts / Q000175:diagnosis* / Q000628:therapy; D002551:Cerebral Ventricle Neoplasms / Q000175:diagnosis* / Q000628:therapy; D003102:Colloids; D004724:Endoscopy; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D013238:Stereotaxic Techniques; D013396:Suction; D014057:Tomography, X-Ray Computed; D017211:Treatment Failure
D003102:Colloids