MR Imaging in Acute Abdominal Pain during Pregnancy-The Effect on Clinical Care

Yehonatan Bar-moshe Kaplan Nadia Liat Appelbaum-Pikarsky Jacob Sosna Naama Lev-Cohain
Department of Radiology, Hadassah-Hebrew University Medical Center, Israel

PURPOSE: Abdominal magnetic resonance imaging (MRI) is the modality of choice in cases of un-clear abdominal pain in pregnant women. We aimed to review a large cohort of MRI studies performed on pregnant patients, in order to evaluate the added value of the MRI on clinical care in this group of patients.

MATERIALS AND METHODS: MRI studies of the abdomen in pregnant patients with acute abdominal and/or pelvic pain performed between the years 2012 - 2018, were included in this study. Multiplanar MR images of the abdomen and pelvis were obtained and independently reviewed by senior radiologists. Correlation with surgical and clinical records both pre and post MRI interpretations were used for correlation.

RESULTS: 183/184 MRI studies where included; average age was 28±5.6 years, among them 33 (18%) patients were in their first trimester (0–13 weeks), 105 (57%) second trimester (14–26 weeks) and 46 (25%) in their third trimester (≥27 weeks). Acute pathology was identified on MRI in 47/184 (25.5%) studies: appendicitis (n = 20), cholidocholitiasis (n = 6), terminal ileitis (n = 4), ovarian torsion (n = 4), pyelonephritis (n=3), small bowel obstraction (n = 2), pancreatitis (n=2), adrenal ischemia (n = 1), small abscess of unknown origin (n = 1), uretrohydronephrosis due to uretral stone (n = 1), bleeding myoma (n = 1), colitis (n=1), and perianal abscess (n=1). 137 / 184 (74%) studies had no acute pathological findings on MR examinations and unremarkable follow-up with spontaneous resolution of the pain. In 17/47 (36 %) cases with positive findings the initial management was altered post MRI according to the study findings. Correlation of retrospective clinical MRI interpretations with surgical and clinical records showed correct identification of disease entities in 44/47 patients. The sensitivity, specificity, positive predictive values (PPV), and negative predictive values (NPV) of MR imaging for acute pathology in correlation to clinical outcome were 100%, 98.5%, 95.6% and 100% retrospectively.

CONCLUSION: MRI is an accurate tool in detecting the cause of acute abdominal and pelvic pain during pregnancy. Our study showed positive findings in quarter of the studies, leading to a considerable changed in the initial diagnosis and management.

Yehonatan Bar-moshe
Yehonatan Bar-moshe