Microcystic Meningioma: The Characteristic Neuroradiologic Findings.

Kim, Seung Hyun; Kim, Dong Gyu; Kim, Chae Yong; Choe, Gheeyoung; Chang, Kee Hyun; Jung, Hee Won

Original Article

Journal of Korean Neurosurgical Society 2003;34(5): 401-406.

Seung Hyun Kim, Dong Gyu Kim, Chae Yong Kim, Gheeyoung Choe, Kee Hyun Chang, Hee Won Jung

¹Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Korea. gknife@plaza.snu.ac.kr
²Department of Pathology, Seoul National University College of Medicine, Seoul, Korea.
³Department of Diagnostic Radiology, Seoul National University College of Medicine, Seoul, Korea.

ABSTRACT

OBJECTIVE
Microcystic meningioma is a rare histological subtype of meningioma, which constitutes about 1.6% of intracranial meningiomas. The authors present the feasibility of preoperative histological diagnosis by characteristic finding of neuroradiologic studies especially magnetic resonance(MR) image. METHODS: Eleven cases were collected retrospectively in the archives of brain tumor registry in the Department of Neurosurgery during recent eight years. There were five men and six women, ranging in age from 37 to 67 years(average, 56.7). All 11 cases had underwent the craniotomy and histological diagnosis of microcystic meningioma had been made. RESULTS: The MR image showed high signal intensity in T2-weighted images and low signal intensity in T1-weighted images. In all cases, peritumoral edema was moderate to severe and location of the masses was in the surface of the brain with dural attachment. MR image after administration of Gd-DTPA showed 2 patterns: pattern I demonstrated homogeneous strong enhancement similar to ordinary meningioma in seven cases and pattern II showed peripheral rim enhancement with low signal intensity inside of tumor masses in four cases. Dural tail sign was seen in all cases. In cerebral angiography, patten I revealed strong vascular tumor staining, however, there was no staining or faint staining in pattern II.
CONCLUSION
Preoperative histological diagnosis of microcystic meningioma should be considered by the characteristic findings of MR image. It may help neurosurgeons to avoid of preoperative radiologic misdiagnosis especially concerning the malignancy.

Key Words: Meningioma; Microcystic; Magnetic resonance image; Angiography; Computed tomography