TITLE: Endolymphatic Sac Tumor
MR images demonstrate an irregular multilobulated and heterogeneous (partially cystic and partially solid) mass involving the petrous portion of the temporal bone. On the T1-weighted images, the mass has high signal intensity. On the T2-weighted images, there are curvilinear serpentine hypointensities, suggestive of vessels, hemosiderin deposition, or calcification. Some of the right petrous mastoid air cells are fluid filled.