American Journal of Roentgenology, Vol 159, 609-612, Copyright © 1992 by American Roentgen Ray Society

ARTICLES

CT and MR imaging findings in adults with cerebellar medulloblastoma: comparison with findings in children

PM Bourgouin, D Tampieri, SZ Grahovac, C Leger, R Del Carpio and D Melancon
Department of Radiology, Montreal Neurological Hospital and Institute, McGill University, Quebec, Canada.

The goal of this study was to determine if certain imaging features suggest the diagnosis of cerebellar medulloblastoma in adults and to determine how often the classic CT appearance seen in children is present in adults. The study included 28 adult patients with proved cerebellar medulloblastoma. The tumor was located in the cerebellar vermis in 14 patients and in a cerebellar hemisphere in 14 patients. Thirteen patients had unenhanced CT of the brain, all patients had contrast-enhanced CT, and eight patients had unenhanced MR imaging. The imaging features in adults were compared with those in children, as described in the literature. In our adult patients, all tumors were hyperdense compared with gray matter on unenhanced CT and showed a slight to moderate increase in density after injection of contrast medium. Thirteen lesions had well-defined margins, and 15 had poorly defined margins. Low-density areas consistent with cystic and necrotic degeneration were detected in 23 (82%) of the 28 tumors. By comparison, in children, medulloblastoma usually originates in the vermis. As in adults, the mass is hyperdense on unenhanced CT, but enhances markedly and homogeneously after injection of contrast medium. Usually no evidence of cyst formation or necrosis is seen, and the tumor margins are well defined. This classic CT appearance of medulloblastoma in children was identified in only three (11%) of the 28 adult patients. Medulloblastoma has a variable MR appearance in both children and adults. On T2-weighted images, lesions are hypo-, iso-, or hyperintense compared with normal gray matter. The CT findings of medulloblastoma in adults usually differ from those of medulloblastoma in children. The tumor has a variable and nonspecific appearance in adults and should always be considered in the differential diagnosis of a mass in the posterior fossa.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				K. K. Koeller and E. J. Rushing From the Archives of the AFIP: Medulloblastoma: A Comprehensive Review with Radiologic-Pathologic Correlation RadioGraphics, November 1, 2003; 23(6): 1613 - 1637. [Abstract] [Full Text] [PDF]

				R. Lopez-Alberola, M. Bhattacharjee, J. Borne, and D. A. Lee Atypical Features of Medulloblastoma on Magnetic Resonance Imaging: Case Report and Review of the Literature J Child Neurol, January 1, 2003; 18(1): 64 - 67. [Abstract] [PDF]

				C. Majos, J. Alonso, C. Aguilera, M. Serrallonga, J. J. Acebes, C. Arus, and J. Gili Adult Primitive Neuroectodermal Tumor: Proton MR Spectroscopic Findings with Possible Application for Differential Diagnosis Radiology, November 1, 2002; 225(2): 556 - 566. [Abstract] [Full Text] [PDF]

				S. P. Meyers, S. L. Wildenhain, J.-K. Chang, E. C. Bourekas, P. F. Beattie, D. N. Korones, D. Davis, I. F. Pollack, and R. A. Zimmerman Postoperative Evaluation for Disseminated Medulloblastoma Involving the Spine: Contrast-enhanced MR Findings, CSF Cytologic Analysis, Timing of Disease Occurrence, and Patient Outcomes AJNR Am. J. Neuroradiol., October 1, 2000; 21(9): 1757 - 1765. [Abstract] [Full Text]