31-year-old female with acute right hemiabdominal pain, nausea, and vomiting.
Acute Uncomplicated Appendicitis in Pregnancy
Rapid T2 (HASTE or SSFSE) and fat saturated T2
If an ultrasound evaluation is inconclusive, MRI is the next best option for appendiceal assessment during pregnancy. It avoids irradiation of the mother and fetus (though it does deposit a subteratogenic dose of heat), and is over 90% sensitive and specific for the detection of acute appendicitis. When the appendix is visualized, MRI is said to have a near 100% negative predictive value. This can be complicated by the progressive superior displacement of the cecum and appendix by the gravid uterus, often placing them in close proximity to the liver by the end of pregnancy. Unsurprisingly, this can lead to an atypical clinical presentation (e.g., right hemiabdominal or RUQ pain rather than RLQ pain).
Pregnant patients are less likely to develop acute appendicitis than age-matched controls (one study suggests a 35% decrease in incidence). It’s only confirmed in one of 800-1500 pregnancies. Unfortunately, pregnant patients develop appendiceal rupture more often, with an associated fetal mortality rate of up to 35%. This is most likely to occur during the third trimester and may be due to delays in diagnosis (e.g., spending hours ruling out obstetric conditions) and a general reluctance to operate during this stage of pregnancy.
General surgery consultation leading to a laparoscopic appendectomy.