Magnetic Resonance (MR) imaging in tongue cancer -special reference to the extent and the radiation effect-

Research Project

Project/Area Number	02807181
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	外科・放射線系歯学
Research Institution	Niigata University
Principal Investigator	NAKAMURA Motoyasu Niigata University, School of Dentistry Assistant Professor, 歯学部, 助教授 (70124774)
Co-Investigator(Kenkyū-buntansha)	HAYASHI Takafumi Niigata University, School of Dentistry Assistant, 歯学部, 助手 (80198845) NAKAYAMA Hitoshi Niigata University, School of Dentistry Assistant, 歯学部附属病院, 助手 (70180437) ITO Jusuke Niigata University, School of Dentistry Professor, 歯学部, 教授 (50018371)
Project Period (FY)	1990 – 1991
Project Status	Completed (Fiscal Year 1991)
Budget Amount *help	¥1,600,000 (Direct Cost: ¥1,600,000) Fiscal Year 1991: ¥600,000 (Direct Cost: ¥600,000) Fiscal Year 1990: ¥1,000,000 (Direct Cost: ¥1,000,000)
Keywords	MR Imaging / Tongue Cancer / T1-Weighted Image / T2-Weighted Image / GD-DTPA / Interstitial Radiotherapy / GDーDTPA
Research Abstract	In tongue cancer the extent had been clinically judged by the degree of the induration and/or the degree of the ulceration. Recently Magnetic Resonance (MR) imaging is being used with increasing frequency in the evaluation of disease in head and neck patients. MR contributes to the imaging of the area by permitting better soft tissue contrast and by its capacity for producing multi planner views. The main purpose of this study is to diagnose the extent of tongue cancer. The second purpose is to evaluate the treatment effect of the tongue cancer by radiation therapy. Six patients of tongue cancer treated by radiation therapy underwent MR imaging. Images were acquired using spin echo (SE) pulse sequences on 1.5T superconducting magnet. T1-weighted images (TR=600, TE=15), T2-weighted images (TR=2000, TE=90) and the images after injections Gd-DTPA were available. T1-weighted sequence shows tumorous mass as an area of low signal intensity compared with normal tongue. T2-weighted sequence shows tumorous mass as higher intensity than surrounding tissues. After Gd-DTPA administration, in T1-weighted images, three different types in tumors were found. (Homogeneous higher intensity, higher intensity near the margin and same intensity as surrounding tissue). Following the interstitial radiotherapy, MR imaging is useful from 1 month later. MR imaging performed in the immediate postbrachytherapy period are worthless for determining tumor response because the hemorrhage, edema and associated soft tissue changes. Following the external radiotherapy, MR imaging is useful after 1month. If T2-weighted image shows high and Gd-DTPA image shows higher intensity than surrounding tissue in post-irradiation image, tumor recurrence may be considered.