For the study, the researchers analyzed the MR images of 29 pregnant patients who had been experiencing acute abdominal pain. In 28 of those cases, the correct diagnosis was made, the one exception being a case of ovarian torsion (twisting of the ovary), which was correctly identified in another of the patients. A total of 14 different causes for the abdominal pain were diagnosed on MRI, including appendicitis, ovarian cysts, hemorrhage and pancreatitis.
According to the researchers, diagnosing acute abdominal pain in pregnant patients can be a difficult task. "Diagnosis is complicated since the enlarged pregnant uterus pushes organs out of their normal locations, so that pain is not in the usual place. Also, there are more possible causes for pain, including not only non-pregnancy associated diseases, but conditions more common in pregnancy and conditions unique to pregnancy," said Richard C. Semelka, MD, one of the authors of the study.
According to the study, CT is normally used for diagnosing abdominal pain, but a considerable dose of radiation is conferred to the fetus and can increase cancer risks in both the fetus and the mother. Sonography, which is safe from radiation, is limited in what it can reveal for diagnosis. "The most compelling aspects about using MRI for evaluating pregnant patients are that it's safe, like ultrasound, both for the developing fetus and the mother and it has a high accuracy for detecting uterine and extra-uterine diseases that is unmatched by either CT or ultrasound," said Dr. Semelka.
The study appears in the February 2005 issue of the American Journal of Roentgenology.
A PDF of the full study is available upon request to reporters.
Journal
American Journal of Roentgenology