Comparison of peritoneal tumor imaging using conventional MR imaging and diffusion-weighted MR imaging with different b values.
OBJECTIVE
The aim of this study was to evaluate the utility of DW MRI with two different b values in identifying peritoneal tumors in oncology patients.


METHODS
Nineteen patients with known malignancy underwent abdominal and pelvic MRI before surgery. MRI included free-breathing DWI with b values of 400 and 800 s/mm2, T1-weighted fat-suppressed spoiled gradient-echo, T2-weighted fat-saturated turbo spin-echo, and 5-min delayed gadolinium-enhanced imaging. Two observers reviewed images for peritoneal tumors at ten anatomic sites within consensus. The results of laparatomy and histopathological evaluation were compared with MRI results. Sensitivity, specificity, and accuracy of identifying peritoneal metastases were calculated for conventional MRI, combined DWI with a b value of 400 s/mm2 and conventional MRI, and combined DWI with a b value of 800 s/mm2 and conventional MRI by consensus of two observers.


RESULTS
One-hundred and twenty-five peritoneal metastasis sites were confirmed by surgical and histopathological findings. Conventional MRI alone identified 72 peritoneal metastases (sensitivity, 0.58; specificity, 0.87; accuracy, 0.67). Combined DWI with a b value of 400 s/mm2 and conventional MRI revealed 106 peritoneal metastases (sensitivity, 0.85; specificity, 0.88; accuracy, 0.85). Finally, combined DWI with a b value of 800 s/mm2 and conventional MRI revealed 103 peritoneal metastases (sensitivity, 0.83; specificity, 0.94; accuracy, 0.86).


CONCLUSIONS
DWI with a high b value provides complementary information that can improve the detection of peritoneal tumors when combined with conventional MRI. We recommend combined MRI and DWI with a high b value for increasing the sensitivity and accuracy of the preoperative detection of peritoneal tumors.
Bozkurt
Mahmut
M
Buhara Private Hospital Department of Radiology, and School of Medicine, Atatürk University, Erzurum, Turkey.
Doganay
Selim
S
Kantarci
Mecit
M
Yalcin
Ahmet
A
Eren
Suat
S
Atamanalp
S Selcuk
SS
Yuce
Ihsan
I
Yildirgan
M Ilhan
MI
D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008536:Meglumine; D008875:Middle Aged; D009362:Neoplasm Metastasis; D010534:Peritoneal Neoplasms / Q000473:pathology* / Q000601:surgery; D010537:Peritoneum / Q000473:pathology*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
D003287:Contrast Media; D008536:Meglumine