Location [Neurosurgery Wiki]

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Imaging is fairly sensitive and specific in affording the diagnosis of this tumor.

On imaging choroid plexus papillomas are characterised by vividly enhancing, usually intraventricular, masses. Hydrocephalus is common. 

===Location===
Unlike most other brain tumours, which are more common in the posterior fossa in children and supratentorial compartment in adults, the relationship is reversed for choroid plexus papillomas:

adults: most often (70%) occur in the fourth ventricle
children: most often occur in the lateral ventricles, with a predilection for the trigone
Third ventricular, cerebellopontine angle, parenchymal and even pineal region tumours have also been described. 

===CT===
The tumours are usually well-defined lobulated masses, either iso- or somewhat hyperdense compared to the adjacent brain. There is associated hydrocephalus. They usually homogeneously enhance, demonstrating with an irregular frond-like pattern, resulting in a cauliflower-like appearance. If there is markedly heterogeneous contrast enhancement, a choroid plexus carcinoma should be suspected 4.

Fine, speckled calcification is seen within the tumour in approximately 25% of cases 4. 

===MRI===
The frond-like morphology of the tumour can usually be seen, especially following contrast administration. Varying degrees of associated hydrocephalus are also present in almost all cases.

T1: typically isointense cf. to adjacent brain; may be somewhat hypointense.

T2
iso to hyperintense

small flow-voids may be seen within the tumour

T1 C+ (Gd): marked enhancement, tends to be homogeneous

MR spectroscopy

decreased NAA

increased Cho
((https://radiopaedia.org/articles/choroid-plexus-papilloma-1)).