Author: Jeremy Horn

NECT CECT MRI - T1 MRI - T2 MRI - FLAIR MRI - Diffusion/ADC MRI - T1 post-contrast Additional Comments
Meningioma Hyperattenuated intraventricular mass +/- calcifications Intense enhancement (no image available). Iso- to hypointense Iso- to hyperintense Hyperintense with peritumoral edema Variable (no image shown) Intense enhancement
   
Metastasis Variable appearance depending on primary malignancy; here seen as a hyperattenuating mass in a woman with intraventricular melanoma Usually enhances, as seen in this case of intraventricular melanoma Heterogeneous; hyperintensity may be seen from hemorrhage Heterogeneous depending on primary malignancy   Intense enhancement Renal and lung most common primaries
   
Lymphoma Usually hyperdense; may have hypointense rim of edema Moderate uniform enhancement; occasionally see ring enhancement   Iso- to hypo-intense to the cortex May show restricted diffussion Homogenous enhancement; can see peripheral enhancement in immunocompromised or with central necrosis  
   
Ependymoma Usually isoattenuating within or adjacent to the ventricles; heterogeneous and may contain calcifications Heterogeneous, usually iso- to hypo-intense (+/- calcifications, cysts, hemorrhage) Heterogeneous, usually iso- to hyper-intense Hyperintense; sharp contrast with CSF Variable (no image)   Moderate heterogeneous enhancement

 

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2/3 infratentorial, within 4th ventricle (often causing hydrocephalus); 1/3 supratentorial in lateral ventricle or periventricular parenchyma. Most common in children.
 
Subependymoma Iso- to hypodense intraventricular mass +/- calcifications Usually little to no enhancement (no image available) Heterogeneous intraventricular mass, hypo- to iso-intense to white matter Heterogeneous hyperintense intraventricular mass Hyperintense intraventricular mass Usually little to no enhancement Rare well-differentiated intraventricular tumor, most commonly arising within fourth ventricle. Extraventricular extension and recurrence both extremely rare.
   
Choroid Plexus Papilloma/Carcinoma Lobular intraventricular mass, usually iso- to hyperdense +/- calcifications, often with associated hydrocephalus. Seen here in the fourth ventricle at the foramen magnum

 

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Intensely enhancing (no image) Lobulated, intraventricular mass Iso- to hyperintense intraventricular mass, usually causing hydrocephalus Hyperintense intraventricular mass Intense, near homogenous enhancement

 

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50% of patient <10 y for lateral ventricle tumors. Fourth ventricular lesions seen in patients 0–50 y. Papilloma difficult to distinguish from carcinoma radiograhpically. MR spectography shows absent NAA, mildly increased choline.
   
Colloid Cyst Located at the foramen of Monro, usually hyperdense (70%) Usually no enhancement (no image available)   Depends on cholesterol content; 2/3 hyperintense, remainder are isointense; +- hydrocephalus Variable signal depending on water content; usually isointense No suppression on FLAIR imaging No diffusion restriction Usually no enhancement; rarely see rim enhancement Characteristically occur at the anterosuperior aspect of the third ventricle and may obstruct the adjacent foramen of Monro.
 
Subependymal Giant Cell Astrocytoma Hypo- to isodense mass near the foramen of Monro +/- calcifications; may see other signs of tuberous sclerosis (including calcified subependymal nodules) Strong heterogeneous enhancement (no image shown) Hypointense +/- calcification Iso- to hyperintense compared to surrounding white matter Strong enhancement Seen in children with tuberous sclerosis. All lesions in lateral ventricle near foramen of Monro, with occasional extension into third ventricle.
     
Central Neurocytoma Mixed solid and cystic mass, most frequently within the frontal horn/body of lateral ventricle, often with calcifications   Heterogeneous enhancement Heterogeneous, isointense to gray matter Heterogeneous, iso- to hyper-intense, with hyperintense cystic regions Heterogeneous, predominantly hyperintense Not defined in the literature; this image demonstrates a large central neurocytoma causing restricted diffusion, confirmed on the ADC map Heterogeneous enhancement, greater than the surrounding brain parenchyma 20-40 y most common. Usually arises in lateral ventricles from the septum pellucidum; occassionally extends into third ventricle.  
   
Neurocysticercosis May see thin wall of cyst within the ventricles; cyst can cause hydrocephalus Most helpful sequence to detect intraventricular cysts. Intensity depends on stage; here see a hyperintense scolex casuing dilatation of the fourth ventricle. Cyst usually hyperintense but masked by hyperintense CSF     Intraventricular cysts less common than cysts located in the subarachnoid space, cisterns, and parenchyma. When intraventricular, cysts are often isolated and can cause obstructive hydrocephalus.