ENDOSCOPIC MRI - PRELIMINARY-RESULTS OF A NEW TECHNIQUE FOR VISUALIZATION AND STAGING OF GASTROINTESTINAL TUMORS

Background and Study Aims: The principle of endoscopic ultrasonography - introducing the transducer of an external imaging method, such as u ltrasonography, in combination with an endoscope into the gastrointest inal tract for higher-resolution imaging - has also been applied to ma gnetic resonance imaging (MRI). We report here on our preliminary expe rience with a new method of endoscopic MRI in the upper gastrointestin al tract. Patients and Methods: Endoscopic MRI was performed in 32 pat ients with esophageal (n = 8) or gastric diseases (n = 24), mostly tum ors (n = 26). Most cancers were at an advanced stage (T3/T4), A protot ype MRI endoscope connected to a 1.5 tesla MRI scanner was used. The a ccuracy of endoscopic MRI in visualizing and staging gastrointestinal lesions was assessed. Results: The normal gastrointestinal wall consis ted of three layers, and tumors were visualized as having a low signal intensity on both T-1- and T-2-weighted sequences. Destruction of the wall layers was found to be characteristic of malignancy, Sufficient images were obtained in seven of eight esophageal cases (88%), but in only 14 of 24 gastric cases (58%). In patients in whom adequate visual ization was achieved, the endoscopic MRT. results of local and regiona l staging were consistent with surgical, histopathological, CT and/or EUS results in all six esophageal cancer cases and in 89% (T stage) an d 56% (T stage) of the nine patients with gastric cancer. Conclusions: These preliminary results of endoscopic MRI are the first to be repor ted in the English literature. They show the potential of the method f or local and regional staging, three-dimensional visualization of lesi ons being a potential advantage. Further technical improvements are ex pected.