Choroid Plexus Papilloma MRI

Clinical details: A 2 y/o female child, h/o inability to maintain posture, inability to walk, delay in developmental milestones.

Enlarged head on inspection.

CHOROID PLEXUS PAPILLOMA

The most benign tumor of  choroid plexus.

Vast majority of choroid plexus papilloma occur in the lateral and fourth ventricle. Atrium is the most common site, usually solitary tumours varying in size from small to large. Occasionally multiple non contigious lesions are seen. Most of the are well circumscribed papillary or cauliflower like masses may adhere but usually do not invade through the ventricular wall.

Histologically the architecture of C.P.Ps closely resemble that of non-neoplastic choroid plexus. A core of fibrovascular connective tissue covered by a single layer of benign appearing epithelial cells is typical. Cytokeratins,Vimentins,and Podoplanin are expressed virtually by all C.P.Ps.
Choroid plexus papillomas are W.H.O grade 1 neoplasm.

C.P.Ps account for less than 1 % of all primary intracranial neoplasm but represent 13% of brain tumors occurring in 1st yr of life. Median age of presentation for lateral and third ventricular C.P.Ps is 1.5 yrs, for 4th ventricular C.P.Ps it is 22.5 yrs. There is slight male preponderance.
Headache,nausea, vomiting with enlarged head size may be seen in children and infants.

IMAGING FINDINGS:
Intra ventricular mass isodense to hyperdense compared to brain parenchyma on CT. Intense homogenous enhancement on post contrast.
A well defined , lobulated intraventricular mass with frond like papillary excression, iso to slightly hypointense compared to brain parenchyma is seen on T1W1, iso-to hyperintense on T2W1 and FLAIR. Linear and branching internal flow voids reflects the increased vascularity within choroid plexus papillomas. T2w images may show hypointense foci secondary to calcification.
Associated hydrocephalus due to overproduction of c.s.f.
Elevated myoinositol on MR spectroscopy.

Dr Prasad Jagdale
Radiology Resident
CNS Hospital, Solapur