Modern imaging of the masseter muscle: normal anatomy and pathosis on CT and MRI.

Tremendous advances in diagnostic imaging technology have produced computed tomography (CT) and magnetic resonance (MR) imaging--new ways to depict the normal anatomy and pathosis of the masseter muscle. This article reviews the masseter muscle's normal appearance on CT and MR images and demonstrates the clarity with which CT, in particular, is able to depict soft tissue lesions and neighboring bony involvement. Analysis of the strengths, weaknesses, and availability of these new techniques leads to the conclusion that CT is currently the test of choice for imaging masseteric lesions but that MR shows greater promise for the future.