Pelvic MRI finds niche assessing infertile women

MRI is underutilized in pelvic imaging, and it's only a matter of time before radiologists and referring physicians are educated about its utility, according to Dr. Elizabeth Sadowski, an assistant professor of radiology at the University of Wisconsin, Madison.

The UW group and researchers from Switzerland presented studies at the RSNA meeting showing dynamic contrast-enhanced MR hysterosalpingography (MR-HSG) to be an excellent noninvasive, nonionzing replacement test for women with infertility problems. The current study of choice is conventional hysterosalpingography (cHSG). However, this requires ionizing radiation, which is counterintuitive to a potentially fertile female, Sadowski said.

Fallopian tube occlusion is the most common abnormality contributing to infertility, affecting 40% of infertile women, Sadowski said. She and her colleagues compared MR-HSG using a 3D TRICKS sequence with cHSG in 16 women to assess tubal patency.

All patent tubes found on cHSG were also found patent by MR-HSG. Of the nine occluded tubes on cHSG, five were patent on MR-HSG. The remaining four occluded tubes on cHSG also showed occlusion on MR-HSG. The difference between the two methods was statistically significant, Sadowski said.

In addition to tubal patency, conventional MRI discovered four subjects with large leiomyomas and three subjects with arcuate uterine configurations, which were suggested on cHSG due to endometrial contour deformity. Sadowski concluded that MR-HSG with 3D TRICKS sequence is comparable if not better than conventional HSG to evaluate tubal patency.

In another study, Dr. Wassilios Pegios, a radiologist at the University Hospital Basel, and colleagues evaluated 37 consecutive infertile women with a dynamic 3D FLASH sequence. MR-HSG allowed good 3D visualization of the uterine cavity and confirmation of bilateral fallopian tube patency in 27 patients.

While MR-HSG costs twice as much as the conventional method, Pegios said that it has several advantages. Patients avoid ionizing radiation, and they can have a comprehensive pelvic exam using anatomical MRI to rule out any uterine anomaly as well as function imaging to assess tubal patency.

The infertility population is increasing astronomically, partly because of technology that helps women have children and partly because women are choosing to have children at an older age, Sadowski said. At UW, high-risk infertile women, those who have failed the conventional evaluation or who have already had problems, go immediately to MRI.

"We use it for patients who have had multiple spontaneous abortions or were going to have hysteroscopy or other tests. It's a one-stop exam," Sadowski said.