Imaging of acute right lower quadrant abdominal pain: Differential diagnoses beyond appendicitis

Evaluation of acute right lower quadrant pain remains a common and challenging clinical scenario for emergency medicine physicians due to frequent nonspecific signs, symptoms, and physical examination findings. Therefore, imaging has evolved to play a pivotal role in the emergency setting. While appendicitis is a common cause for acute pain, there are numerous other important differential considerations with which the radiologist must be aware. The purpose of this review is to list an anatomybased, encompassing differential diagnosis in addition to acute appendicitis for right lower quadrant pain; demonstrate the key imaging findings of numerous differential considerations; and describe helpful imaging and clinical features useful in narrowing the differential diagnosis. © Am Soc Emergency Radiol 2011.