Interventional radiologists should routinely use pelvic MRI to assess women prior to uterine fibroid embolization, according to research presented at the 27th annual meeting of the Society of Cardiovascular and Interventional Radiology in Baltimore.

Researchers at Northwestern University Medical School in Chicago asked five interventional radiology attending physicians at a single university hospital to prospectively complete questionnaires before and after MRI was obtained in their evaluation of women presenting for potential UFE, according to Dr. Reed A. Omary, a professor of radiology at Northwestern.

The questionnaires posed three queries to the physicians:

• What is your single most likely diagnosis prior to MR?
• What is your diagnostic confidence of this single diagnosis (in terms of 0% to 100% certainty)?
• What is your anticipated treatment plan prior to MR and what was your final treatment post-MR?

Diagnostic choices included fibroids, adenomyosis, endometrial diseases, adnexal masses, and multifactorial. Treatment choices were clinical management, biopsy, UFE, and surgery. Pelvic MR scans included axial/sagittal T2-weighted and pre/post-gadolinium-enhanced T1-weighted images.

The IRs completed 60 consecutive questionnaires. Before MRI, mean diagnostic confidence was 76%, while after MRI, it was 98%. MRI thus caused a mean gain in diagnostic confidence of 22%, Omary said.

MRI changed the initial diagnoses of IRs in 11 patients (18%). Initial treatment plans changed in 12 patients (20%). Before MRI, 57/60 (95%) women were anticipated to receive UFE, but after MRI, UFE was not recommended in 10 of these 57 (18%) women. In these 10 women, IRs recommended surgery for eight, clinical management for one, and biopsy for one.

"Interventional radiologists increasingly use pelvic MRI for this population, but the effect MR has on altering the diagnoses and treatment decisions had not been known," Omary said. "Now we know that MR significantly alters the diagnoses and treatment plans of IRs evaluating women with presumed symptomatic fibroids."

An audience member commented that since MR is expensive, he'd like to see it compared with high-quality ultrasound.

Omary answered that, anecdotally, they had many patients who had had an ultrasound that showed diffuse fibroids.

"Before MR, 98% of this population were thought to have fibroids. That dropped to 83% after MR," he said.

-- By C.P. Kaiser