ENDOSCOPIC MRI USING 3D-SPOILED GRASS (SPGR) SEQUENCE FOR LOCAL STAGING OF RECTAL-CARCINOMA

Objective: Magnetic resonance imaging was performed with an MR endosco pe to evaluate the depth of invasion of rectal carcinomas. Materials a nd Methods: Twenty-two patients with rectal carcinomas were studied pr ior to surgery with MRI using a 3D-fast spoiled GRASS (SPGR) sequence, a nonmagnetic endoscope and an antenna probe. Results: The MR images on 3D-fast SPGR sequence showed that the normal bowel mucosa had a hig h signal intensity, the submucosal layer had a low signal intensity, a nd the muscularis propria had moderate signal intensity. Small tumors had moderate signal intensity similar to the muscularis propria. Advan ced tumors with considerable volume revealed heterogeneous findings wi th intermediate and low signal intensities. The depth of wall invasion by rectal carcinoma was correctly staged with endoscopic MRI in 16 of 22 patients. Conclusion: This technique may be useful for the accurat e staging of the depth of invasion by rectal carcinomas.