J Korean Radiol Soc.
1996 Jan;34(1):15-20.
MRI Findings of Vermian Medulloblastoma
- Affiliations
-
- 1Department of Radiology, Catholic University Medical College, Korea.
Abstract
- PURPOSE
To find characteristic MRI features of vermian medulloblastoma.
MATERIALS AND METHODS
MRI studiesand medical records were retrospectively reviewed for 12 patients with surgically proven midline medulloblastoma. The assessment concerned appearance of the mass in relation to surrounding structures ; MR signal intensity ; the enhancement pattern ; the mass's location and size ; presence of a cystic/necrotic area, calcification, or vascular void ; extension through the foramen Luschka ; degree of hydrocephalus ; and presence of tonsillarherniation.
RESULTS
The midline medulloblastoma commonly showed roundish moon-surface appearance, especially onthe axial T2-weighted images. All tumors showed heterogeneous signal intensities mainly due to intratumoralcystic/necrotic or hemorrhagic changes. The tumors were commonly located at mid- and/or inferior vermis. Occasionally the tumors extended through the foramen Luschka, and caused obstructive hydrocephalus of moderate tosevere degree. Post-con-trast study showed heterogeneous, dense contrast enhancement in the majority of patients.
CONCLUSION
The MR finding of the moon-surface appearance formed by both the mass and the intratumoralcystic/necrotic change as seen on axial T2-weighted images could be helpful in the diagnosis of vermianmedulloblastoma.
