Pinealoma 04

Pinealoma: (Left) T2-weighted axial MRI; (Right) Flair axial MRI. Note the hydrocephalus and associated transependymal edema, best seen on the Flair scan (right image). Also note the advantage of the Flair scan compared to the T2-weighted scan in distinguishing edema from CSF. On the T2-weighted image, it is not possible to distinguish transependymal edema from CSF in the ventricle, since both are bright. However, on the Flair image the differentiation is straightforward because CSF is dark while transependymal edema remains bright. Surgical excision showed that the lesion was a pinealoma.

Tumors that arise from cells in the pineal gland are known as pinealomas. As the pineal gland is located in the posterior third ventricle, pineal tumors often present with non-communicating hydrocephalus due to compression of the cerebral aqueduct. In addition, downward pressure may compress the dorsal midbrain, resulting in a Parinaud's syndrome (lid retraction, large pupils that react poorly to light, impaired upgaze, and convergence retraction nystagmus).