MR Imaging of Squamous Cell Carcinoma of the Floor of the Mouth

Purpose: To determine the diagnostic value of MR imaging for tumors of the floor of the mouth and the effects of the tumors on the sublingual and submandibular glands.Material and Methods: Thirty-seven patients with proven squamous cell carcinoma of the floor of the mouth underwent MR imaging, including unenhanced T1-weighted, T2-weighted, dynamic, and contrast-enhanced T1-weighted images. the appearance of the tumor and the sublingual and submandibular glands was assessed qualitatively and quantitatively.Results: All tumors demonstrated replacement of the normal signal intensity in the adjacent sublingual gland. Twenty-one patients (57%) had abnormal signal intensity of the submandibular gland without tumor invasion, presumably secondary to submandibular duct obstruction by the tumor. Unenhanced T1-weighted images provided high contrast between tumor and sublingual gland. Tumors limited within the gland were well detected on unenhanced T1-weighted images. Large tumors extending beyond the gland were well...