Squamous cell carcinoma of the oral cavity: MR findings and value of T1-versus T2-weighted fast spin-echo images.

The purposes of this study were to describe the characteristics of squamous cell carcinomas of the oral cavity on unenhanced and contrast-enhanced T1-weighted spin-echo (SE) MR images and unenhanced T2-weighted fast spin-echo (FSE) MR images and to determine which sequences best delineate the margins and extent of the tumors.Forty-four patients with proved squamous cell carcinoma of the oral cavity (tongue, 24; floor of mouth, seven; buccal mucosa, four; maxillary gingiva, two; and mandibular gingiva, seven) underwent unenhanced axial T2-weighted FSE MR imaging and unenhanced and enhanced axial and coronal T1-weighted SE MR imaging. The appearance, signal characteristics, and extent of the tumors were assessed, and the delineation of tumor margins with each sequence or combination of sequences was evaluated by use of a grading system ranging from 1 (poor) to 3 (excellent). Three patients were excluded because of artifacts on the MR images caused by dental restorations.Tumors in all 41 patients were depict...