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
- 97 Dural Venous Sinus Thrombosis
- 98 Dural Arteriovenous Fistula
- 99 Subarachnoid Hemorrhage
- 100 Laminar Necrosis
- 101 Neurocutaneous Melanosis
- 102 Superficial Siderosis
- 103 Polymicrogyria
- 104 Seizure-Related Changes (Peri-Ictal MRI Abnormalities)
- 105 Embolic Infarcts
- 106 Focal Cortical Dysplasia
- 107 Tuberous Sclerosis Complex
- 108 Dysembroplastic Neuroepithelial Tumor (DNT, DNET)
- 109 Nonketotic Hyperglycemia With Hemichorea–Hemiballismus
- 110 Hyperdensity Following Endovascular Intervention
- 111 Early (Hyperacute) Infarct
- 112 Acute Disseminated Encephalomyelitis (ADEM)
- 113 Susac Syndrome
- 114 Diffuse Axonal Injury
- 115 Multiple Sclerosis
- 116 Progressive Multifocal Leukoencephalopathy (PML)
- 117 Nodular Heterotopia
- 118 Neurosarcoidosis
- 119 Meningeal Carcinomatosis
- 120 Meningitis (Infectious)
- 121 Perineural Tumor Spread
- 122 Moyamoya
- 123 Central Nervous System Vasculitis
- 124 Subacute Infarct
- 125 Active Multiple Sclerosis
- 126 Capillary Telangiectasia
- 127 Developmental Venous Anomaly
- 128 Immune Reconstitution Inflammatory Syndrome (IRIS)
- 129 Ventriculitis
- Section 5 Primarily Extra-Axial Focal Space-Occupying Lesions
- Section 6 Primarily Intra-Axial Masses
- Section 7 Intracranial Calcifications
- Index
- References
108 - Dysembroplastic Neuroepithelial Tumor (DNT, DNET)
from Section 4 - Abnormalities Without Significant Mass Effect
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
- 97 Dural Venous Sinus Thrombosis
- 98 Dural Arteriovenous Fistula
- 99 Subarachnoid Hemorrhage
- 100 Laminar Necrosis
- 101 Neurocutaneous Melanosis
- 102 Superficial Siderosis
- 103 Polymicrogyria
- 104 Seizure-Related Changes (Peri-Ictal MRI Abnormalities)
- 105 Embolic Infarcts
- 106 Focal Cortical Dysplasia
- 107 Tuberous Sclerosis Complex
- 108 Dysembroplastic Neuroepithelial Tumor (DNT, DNET)
- 109 Nonketotic Hyperglycemia With Hemichorea–Hemiballismus
- 110 Hyperdensity Following Endovascular Intervention
- 111 Early (Hyperacute) Infarct
- 112 Acute Disseminated Encephalomyelitis (ADEM)
- 113 Susac Syndrome
- 114 Diffuse Axonal Injury
- 115 Multiple Sclerosis
- 116 Progressive Multifocal Leukoencephalopathy (PML)
- 117 Nodular Heterotopia
- 118 Neurosarcoidosis
- 119 Meningeal Carcinomatosis
- 120 Meningitis (Infectious)
- 121 Perineural Tumor Spread
- 122 Moyamoya
- 123 Central Nervous System Vasculitis
- 124 Subacute Infarct
- 125 Active Multiple Sclerosis
- 126 Capillary Telangiectasia
- 127 Developmental Venous Anomaly
- 128 Immune Reconstitution Inflammatory Syndrome (IRIS)
- 129 Ventriculitis
- Section 5 Primarily Extra-Axial Focal Space-Occupying Lesions
- Section 6 Primarily Intra-Axial Masses
- Section 7 Intracranial Calcifications
- Index
- References
Summary
Specific Imaging Findings
On CT, dysembryoplastic neuroepithelial tumor (DNT or DNET) appears as a low density cortico-subcortical supratentorial area. Calcifications are rare. Remodeling of the adjacent calvarium is frequent with superficially located tumors. On MRI, the classic appearance is of a well-demarcated pseudocystic lesion, strongly T2 hyperintense and T1 hypointense with variable signal on FLAIR images. Mass effect is minimal to absent, there is no surrounding vasogenic edema. DNTs may have a triangular-shaped pattern with the base along the cortical surface with preserved gyral pattern. Thin hyperintense signal on FLAIR images is visible both along the surface (bright rim) and as stripes along thin internal septa, resulting in a very characteristic multicystic, “bubbly” appearance. Additional small cysts, separated from the main mass, are often located in the neighboring cortex or subcortical white matter. Some lesionsmay show a more heterogeneous signal consistent with solid, cystic, or semiliquid structures. Solid components may either be solitary or form a multinodular pattern interspersed within a cystic frame. Contrast enhancement is rare, variable, and more often ringlike. Bleeding is also rare. Tumors show increased diffusivity with high ADC values and low rCBV on perfusion imaging. The MRS pattern is nonspecific with increase in mI/Cr and Cho/NAA ratios. Lactate and lipid peaks are usually absent.
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- Information
- Brain Imaging with MRI and CTAn Image Pattern Approach, pp. 223 - 224Publisher: Cambridge University PressPrint publication year: 2012