Periampullary tumors: high-spatial-resolution MR imaging and histopathologic findings in ampullary region specimens.
OBJECTIVE
To prospectively determine the magnetic resonance (MR) signal intensity characteristics of structures of the ampullary region and to assess the potential use of MR imaging in evaluation of the extent of periampullary tumors in resected specimens.


METHODS
Twenty-five specimens from the ampullary region obtained in four autopsy cases without periampullary tumors and in 21 patients with periampullary tumors were examined with a 1.5-T MR system and a circular surface coil with 5-inch (12.7-cm) diameter. High-spatial-resolution MR images were obtained with field of view of 100 x 100 mm, matrix of 256 x 256 or 512 x 256, and section thickness of 2 mm. MR imaging findings were compared with histopathologic findings. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of high-spatial-resolution MR imaging for assessment of tumor invasion into surrounding tissues were evaluated by two radiologists.


RESULTS
T1- and T2-weighted MR images clearly depicted normal structures in the ampullary region that included Oddi muscle, duodenal wall, common bile duct, and pancreas; these findings corresponded well with histologic findings. In 20 (95%) of 21 tumors, high-spatial-resolution MR imaging depicted location and extension of periampullary tumors precisely. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of high-spatial-resolution MR imaging for assessment of tumor invasion into surrounding tissue were 88%, 100%, 96%, 100%, and 94%, respectively.


CONCLUSIONS
In this study, MR imaging correctly depicted location, extension, and origin of tumor. High-spatial-resolution MR imaging has potential for presurgical staging of tumors in this region.
Sugita
Reiji
R
Department of Radiology, NTT East Tohoku Hospital, 2-29-1 Yamatomachi, Wakabayashi-ku, Sendai, Japan. reiji.s@thk.mhc.east.ntt.co.jp
Furuta
Akemi
A
Ito
Kei
K
Fujita
Naotaka
N
Ichinohasama
Ryou
R
Takahashi
Shoki
S
D000368:Aged; D014670:Ampulla of Vater / Q000473:pathology; D003135:Common Bile Duct / Q000473:pathology; D003138:Common Bile Duct Neoplasms / Q000175:diagnosis* / Q000473:pathology; D004379:Duodenal Neoplasms / Q000175:diagnosis* / Q000473:pathology; D004386:Duodenum / Q000473:pathology; D005260:Female; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D010179:Pancreas / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000175:diagnosis* / Q000473:pathology; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D009803:Sphincter of Oddi / Q000473:pathology