Fig 5.

MR images obtained in a 70-year-old man with skin cancer who had progressive right facial nerve weakness. Cross-sectional CT (not shown) and MR imaging were performed to evaluate the patient’s facial weakness and preauricular pain.

A, Axial nonenhanced T1-weighted image (600/14) shows a subtle area of soft tissue (arrowheads) posterior and medial to the ramus of the mandible (R) on the right side that is abnormal when compared with the left.

B, Gadolinium-enhanced fat-suppressed T1-weighted image (500/14) obtained at the same level as in A shows marked enhancement of the area of abnormal soft tissue (arrowheads) in A. This finding was interpreted as normal at an outside institution.

C, Repeat nonenhanced T1-weighted image (600/14) obtained 12 months after the first MR examination shows the extensive progression of the tumor (arrows), with now obvious infiltration of the parapharyngeal space on the right.

D and E, Coronal (D) and axial (E) contrast-agent–enhanced T1-weighted images (600/14) show the growth of the tumor along V₃ (arrowheads in D) into the Meckle cave (solid arrow in E) and cavernous sinus (arrowheads in E). Note the normal appearance of the Meckle cave on the left side (open arrow in E).