Book contents
- Frontmatter
- Contents
- List of contributors
- List of abbreviations
- Preface
- Section 1 Bilateral Predominantly Symmetric Abnormalities
- Section 2 Sellar, Perisellar and Midline Lesions
- Section 3 Parenchymal Defects or Abnormal Volume
- Section 4 Abnormalities Without Significant Mass Effect
- Section 5 Primarily Extra-Axial Focal Space-Occupying Lesions
- Section 6 Primarily Intra-Axial Masses
- 152 Acute Infarction
- 153 Glioblastoma Multiforme
- 154 Therapy-Induced Cerebral Necrosis (Radiation Necrosis)
- 155 Non-Hemorrhagic Metastases
- 156 Cerebral Abscess
- 157 Cerebral Toxoplasmosis
- 158 Primary CNS Lymphoma
- 159 Tumefactive Demyelinating Lesion
- 160 Tuberculoma
- 161 Oligodendroglioma
- 162 Low-Grade Diffuse Astrocytoma
- 163 Gliomatosis Cerebri
- 164 Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke-Like Episodes (MELAS)
- 165 Pleomorphic Xanthoastrocytoma (PXA)
- 166 Ganglioglioma
- 167 Neurocysticercosis – Parenchymal
- 168 Dilated Perivascular Spaces
- 169 Neuroepithelial Cyst
- 170 Subependymal Giant Cell Astrocytoma (SEGA)
- 171 Subependymoma
- 172 Ependymoma
- 173 Pilocytic Astrocytoma
- 174 Medulloblastoma
- 175 Hemangioblastoma
- 176 Lhermitte–Duclos (Cowden Syndrome)
- 177 Hypertensive Hematoma
- 178 Amyloid Hemorrhage – Cerebral Amyloid Angiopathy
- 179 Cortical Contusion
- 180 Hemorrhagic Neoplasms
- 181 Hemorrhagic Venous Thrombosis
- 182 Arteriovenous Malformation
- 183 Cavernous Angioma (Cavernoma)
- Section 7 Intracranial Calcifications
- Index
- References
172 - Ependymoma
from Section 6 - Primarily Intra-Axial Masses
Published online by Cambridge University Press: 05 August 2013
- Frontmatter
- Contents
- List of contributors
- List of abbreviations
- Preface
- Section 1 Bilateral Predominantly Symmetric Abnormalities
- Section 2 Sellar, Perisellar and Midline Lesions
- Section 3 Parenchymal Defects or Abnormal Volume
- Section 4 Abnormalities Without Significant Mass Effect
- Section 5 Primarily Extra-Axial Focal Space-Occupying Lesions
- Section 6 Primarily Intra-Axial Masses
- 152 Acute Infarction
- 153 Glioblastoma Multiforme
- 154 Therapy-Induced Cerebral Necrosis (Radiation Necrosis)
- 155 Non-Hemorrhagic Metastases
- 156 Cerebral Abscess
- 157 Cerebral Toxoplasmosis
- 158 Primary CNS Lymphoma
- 159 Tumefactive Demyelinating Lesion
- 160 Tuberculoma
- 161 Oligodendroglioma
- 162 Low-Grade Diffuse Astrocytoma
- 163 Gliomatosis Cerebri
- 164 Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke-Like Episodes (MELAS)
- 165 Pleomorphic Xanthoastrocytoma (PXA)
- 166 Ganglioglioma
- 167 Neurocysticercosis – Parenchymal
- 168 Dilated Perivascular Spaces
- 169 Neuroepithelial Cyst
- 170 Subependymal Giant Cell Astrocytoma (SEGA)
- 171 Subependymoma
- 172 Ependymoma
- 173 Pilocytic Astrocytoma
- 174 Medulloblastoma
- 175 Hemangioblastoma
- 176 Lhermitte–Duclos (Cowden Syndrome)
- 177 Hypertensive Hematoma
- 178 Amyloid Hemorrhage – Cerebral Amyloid Angiopathy
- 179 Cortical Contusion
- 180 Hemorrhagic Neoplasms
- 181 Hemorrhagic Venous Thrombosis
- 182 Arteriovenous Malformation
- 183 Cavernous Angioma (Cavernoma)
- Section 7 Intracranial Calcifications
- Index
- References
Summary
Specific Imaging Findings
On CT, ependymomas are usually iso- to hypodense compared with normal brain. Approximately 50% contain internal calcifications and hemorrhage can also be seen in approximately 10% of tumors. The tumor is heterogenous, T1 iso- to hypointense, and hyperintense on T2-weighted imaging. T1 hyperintense and T2 hypointense areas may be found, representing calcifications and sometimes blood products. The lesions are frequently heterogenous on ADC maps, the more solid portion of the tumor is generally slightly brighter than the normal brain; anaplastic (higher grade) ependymomas may contain dark areas of very low diffusion. Following contrast, ependymomas show some degree of usually heterogenous enhancement, although non-enhancing tumors can occasionally be seen, especially with recurrent disease. Perfusion studies demonstrate markedly elevated cerebral blood volume (but, unlike other glial neoplasms, poor return to baseline). Due to the propensity for leptomeningeal disease and drop metastases, imaging of the entire neural axis is required. A fourth ventricle mass that extends through the foramina of Luschka and Magendie into the cerebellopontine angle and cisterna magna is a characteristic appearance of the infra-tentorial ependymomas. Supratentorial ependymomas are commonly extraventricular, located along or near the ventricular margin within the cerebral hemispheres; they also tend to be larger and more heterogenous and are frequently anaplastic.
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- Information
- Brain Imaging with MRI and CTAn Image Pattern Approach, pp. 355 - 356Publisher: Cambridge University PressPrint publication year: 2012