MRI of acute abdominal and pelvic pain in pregnant patients.

OBJECTIVE: The purpose of this study was to show the usefulness of MRI in the evaluation of pregnant women with acute abdominal or pelvic pain.

SUBJECTS AND METHODS: All MRI studies of pregnant patients who were referred for examination because of acute abdominal or pelvic pain between June 2002 and May 2004 were included in this study (n=29). The use of MRI was at the discretion of the clinician. Fetal sonography was performed in all patients before any other imaging. A complete abdominal sonographic examination was performed in six patients before MRI. In the remaining 23 patients, MRI was the choice for primary imaging. Multiplanar multisequence MR images of the abdomen and pelvis were obtained in each patient. Unenhanced images were reviewed by an experienced radiologist to determine whether a diagnosis could be made without the administration of gadolinium. In 22 of 29 studies, gadolinium was not administered. The prospective clinical MR interpretations were compared with follow-up medical, surgical, and obstetric records to determine the correctness of the interpretation. All patients were followed up until the date of article submission or until the date of final chart entry.

RESULTS: Correlation of prospective clinical MR interpretations with follow-up medical records showed correct identification of disease entities in all but one patient. In one patient, torsion of the ovary was neither described prospectively nor seen in retrospect. The following disease processes were correctly identified using MRI: appendiceal abscess (n=1), appendicitis (n=2), intraabdominal and rectus muscle abscess (n=1), intussusception (n=1), pancreatitis (n=1), ulcerative colitis (n=1), Crohn's disease with diffuse peritoneal inflammation (n=1), bilateral adrenal hemorrhage (n=1), pyelonephritis (n=2), hydronephrosis (n=1), uterine fibroid degeneration (n=2), degeneration and torsion of a submucosal uterine fibroid (n=1), simple ovarian cysts (n=1), and ovarian torsion (n=1). Twelve of the 29 patients had normal findings on MR examinations and unremarkable follow-up.

CONCLUSION: The intrinsic safety of MRI and its ability to accurately show abdominal and pelvic disease in pregnant patients make it highly useful in the evaluation of these patients.