Pineal Region

Case A: A CT scan demonstrates a well-defined mass in the pineal region that is intrinsically hyperdense to brain parenchyma and has centrally positioned “engulfed” calcification. MRI confirms a homogeneously enhancing pineal region mass located directly beneath the internal cerebral veins that nearly follows the signal intensity of gray matter on T1- and T2-weighted images, infiltrates the margins of the thalamus, and demonstrates restricted diffusion.

Case B: A CT scan demonstrates a pineal region mass that is intrinsically hyperdense to brain parenchyma and has peripheral “exploded” calcification. It nearly follows the signal intensity of gray matter on T1- and T2-weighted images, enhances after the administration of contrast material, and demonstrates restricted diffusion.

Case C: A sagittal postcontrast T1-weighted image demonstrates abnormal thickening and enhancement of the pituitary stalk extending into the optic chiasm, as well as a synchronous enhancing mass lesion within the pineal region.