M Sumi1, M Izumi, K Yonetsu, T Nakamura. 1. Department of Radiology and Cancer Biology, Nagasaki University School of Dentistry, Japan.
Abstract
BACKGROUND AND PURPOSE: MR imaging has been proved to be effective in depicting wide variety of pathologic changes of the salivary gland. Therefore, we evaluated clinical usefulness of MR imaging for sialolithiasis. METHODS: Sixteen patients with sialolithiasis of the submandibular gland underwent MR imaging. MR images of the glands were obtained with a conventional (T1-weighted), fast spin-echo (fat-suppressed T2-weighted) and short inversion time-inversion recovery sequences. Contrast enhancement was not used. MR imaging features then were compared with clinical symptoms, histopathologic features of excised glands, and CT imaging features. RESULTS: Submandibular glands with sialolithiasis could be classified into three types on the basis of clinical symptoms and MR imaging features of the glands. Type I glands were positive for clinical symptoms and MR imaging abnormalities, and were characterised histopathologically by active inflammation (9 [56%] of 16). Type II glands were negative for clinical symptoms and positive for MR imaging abnormalities (4 [25%] of 16), and the glands were replaced by fat. Type III glands were negative for clinical symptoms and MR imaging abnormalities (3 [19%] of 16). CT features of these glands correlated well with those of MR imaging. CONCLUSION: These results suggest that MR imaging features may reflect chronic and acute obstruction, and a combination of CT and MR imaging may complement each other in examining glands with sialolithiasis.
BACKGROUND AND PURPOSE: MR imaging has been proved to be effective in depicting wide variety of pathologic changes of the salivary gland. Therefore, we evaluated clinical usefulness of MR imaging for sialolithiasis. METHODS: Sixteen patients with sialolithiasis of the submandibular gland underwent MR imaging. MR images of the glands were obtained with a conventional (T1-weighted), fast spin-echo (fat-suppressed T2-weighted) and short inversion time-inversion recovery sequences. Contrast enhancement was not used. MR imaging features then were compared with clinical symptoms, histopathologic features of excised glands, and CT imaging features. RESULTS: Submandibular glands with sialolithiasis could be classified into three types on the basis of clinical symptoms and MR imaging features of the glands. Type I glands were positive for clinical symptoms and MR imaging abnormalities, and were characterised histopathologically by active inflammation (9 [56%] of 16). Type II glands were negative for clinical symptoms and positive for MR imaging abnormalities (4 [25%] of 16), and the glands were replaced by fat. Type III glands were negative for clinical symptoms and MR imaging abnormalities (3 [19%] of 16). CT features of these glands correlated well with those of MR imaging. CONCLUSION: These results suggest that MR imaging features may reflect chronic and acute obstruction, and a combination of CT and MR imaging may complement each other in examining glands with sialolithiasis.