Peritumoral Brain Edema in Meningiomas : Correlation of Radiologic and Pathologic Features

OBJECTIVE: The primary objective of this study was to perform a retrospective evaluation of the radiological and pathological features influencing the formation of peritumoral brain edema (PTBE) in meningiomas. METHODS: The magnetic resonance imaging (MRI) and pathology data for 86 patients with meningiomas, who underwent surgery at our institution between September 2003 and March 2009, were examined. We evaluated predictive factors related to peritumoral edema including gender, tumor volume, shape of tumor margin, presence of arachnoid plane, the signal intensity (SI) of the tumor in T2-weighted image (T2WI), the WHO histological classification (GI, GII/GIII) and the Ki-67 antigen labeling index (LI). The edema-tumor volume ratio was calculated as the edema index (EI) and was used to evaluate peritumoral edema. RESULTS: Gender (p=0.809) and pathological finding (p=0.084) were not statistically significantly associated with peritumoral edema by univariate analysis. Tumor volume was not correlated with the volume of peritumoral edema. By univariate analysis, three radiological features, and one pathological finding, were associated with PTBE of statistical significance: shape of tumor margin (p=0.001), presence of arachnoid plane (p=0.001), high SI of tumor in T2WI (p=0.001), and Ki-67 antigen LI (p=0.049). These results suggest that irregular tumor margins, hyperintensity in T2WI, absence of arachnoid plane on the MRI, and high Ki-67 LI can be important predictive factors that influence the formation of peritumoral edema in meningiomas. By multivariate analysis, only SI of the tumor in T2WI was statistically significantly associated with peritumoral edema. CONCLUSION: Results of this study indicate that irregular tumor margin, hyperintensity in T2WI, absence of arachnoid plane on the MRI, and high Ki-67 LI may be important predictive factors influencing the formation of peritumoral edema in meningiomas.

Chronic Subdural Hematoma after Spontaneous Intracranial Hypotension : A Case Treated with Epidural Blood Patch on C1-2

Spontaneous cerebrospinal fluid (CSF) leak is a recognized cause of spontaneous intracranial hypotension (SIH). Subdural hematoma (SDH) is a serious but rare complication of SIH. An autologous epidural blood patch at the CSF-leak site can effectively relieve SIH. We report a case of bilateral SDH with SIH caused by a CSF leak originating at the C1-2 level. A 55-year-old male complained of orthostatic headache without neurological signs. His symptoms did not respond to conservative treatments including bed rest, hydration and analgesics. Magnetic resonance imaging showed a subdural hematoma in the bilateral fronto-parietal region, and computed tomography (CT) myelography showed a CSF leak originating at the C1-2 level. The patient underwent successful treatment with a CT-guided epidural blood patch at the CSF-leak site after trephination for bilateral SDH.