ISRA May 2022

Findings on Emergent Magnetic Resonance Imaging in Pregnant Patients with Suspected Appendicitis: A Single Center Perspective

Hila Bufman 1 Daniel Raskin 1 Yiftach Barash 1 Roy Mashiach 2 Noam Tau 1
1Diagnostic radiology, Sheba Medical Center, Israel
2obstetrics and gynecology, Sheba Medical Center, Israel

Purpose of study: Right lower quadrant (RLQ) pain during pregnancy is a common complaint that poses a diagnostic challenge given the limitation in use of ionizing radiation and changes in anatomy, which limits the diagnostic yield of ultrasound. Given these limitations, there is an increase in use of magnetic resonance imaging (MRI) in the acute setting of RLQ pain in pregnant patients. Here, we describe the most common findings on MRI performed to rule out appendicitis during pregnancy.

Methods: In this institutional review board approved study, we retrospective assessed pregnant patients with suspected appendicitis that underwent non-contrast enhanced MRI. We reviewed the MRI images and collected data from the electronic files to assess for possible pathology to explain the patients` presentation.

Results: 93 women were included in this study The median age was 30 years. The median gravidity number was 2; median parity was 1. The median gestational age was 19 weeks.
88 patients (94.6%) underwent ultrasound prior to MRI, with 62/88 (70.4%) reported as negative for pathological findings; 3/88 (3.4%) were positive for acute appendicitis; 12/88 (13.6%) were inconclusive; and 11/88 (12.5%) offered an alternative diagnosis.
Out of 93 women who underwent MRI, 18 (19.3%) were positive for acute appendicitis. 27 patients (29%) had an alternative pathology: gynecological (14), urological (4) and surgical (3).
After MRI, 55/93 (59.1%) patients received no treatment; 18 patients (19.3%) received antibiotic treatment; and 20/93 (21.5%) patients underwent surgery, 19/20 (95%) were appendectomies. Of the 19 appendectomies, 18 were MRI and pathology proven, one was normal on post-operative pathological assessment. One patient underwent surgery for an ectopic pregnancy.

Conclusions: In our cohort, emergent MRI for acute RLQ pain in pregnant patients found an explanation for the patients` complaints in nearly half the patients. Alternative diagnoses proposed on MRI included gynecological and urological causes.