DWI boosts MR depiction of peritoneal metastases

Diffusion-weighted imaging can significantly improve the accuracy of conventional MR imaging of peritoneal metastases, according to a study released at the 2007 ISMRM meeting.

Dr. Russell N. Low, medical director of Sharp and Children's MRI Center in San Diego, enrolled 17 women and seven men with primary malignancies of the ovaries, colon, pancreas, breast, bladder, and gastrointestinal tract. Patients underwent preoperative abdominal and pelvic MR scanning at 1.5T. A site-by-site comparison of DWI, MRI, and combined DWI/MRI results with surgical and biopsy evaluations underscored the advantage of using DWI and MRI together.

DWI/MRI identified 141 of 153 sites of confirmed peritoneal tumor, with a sensitivity, specificity, and accuracy of 92%, 92%, and 93%, respectively, compared with 78%, 86%, and 82% for MRI alone. DWI bolstered readers' confidence in 75% of the cases and uncovered additional lesions in 63% of them.