Radiology Case of the Month
November 2018

Noncontrast Head CT images demonstrate a focal area of hyperdensity about the medial aspect
of the right cerebellum adjacent to the fourth ventricle (yellow arrows).

1.) With regards to the above images from non-contrast head CT, please select whichever applies:

→ A.) There is intracranial hemorrhage.
B.) There is a ruptured brain aneurysm
C.) There is acute obstructive hydrocephalus
D.) There is a meningioma of the roof the fourth ventricle

Postcontrast images demonstrate a focal area of blooming at the previously seen site of high density on CT at the right medial margin of the fourth ventricle without enhancement on postcontrast (yellow arrow) representing cavernoma. There is also demonstration of caput medusae appearance of small branching veins draining into a single vein adjacent to this lesion (red arrow) suggestive of a deep venous anomaly (DVA).

2.) With regards to the above images from MRI with and without contrast, please select whichever applies:

→ A.) There is a vascular malformation
B.) There is a thrombosed posterior circulation aneurysm
C.) There is an enhancing mass in the fourth ventricle
D.) This is a neurosurgical emergency and requires urgent endovascular coiling