A 13-year-old girl presented with 5 days of abdominal pain that originated in her right upper quadrant and progressed to her epigastrium. She denied experiencing nausea, vomiting, diarrhea, loss of appetite, fevers, or chills. She was afebrile. Her abdomen was tender to palpation in the midepigastrium, but without rebounding or guarding. White blood cell count and lipase and liver function test results were normal. Her weight was 64.7 kg (~ 90th percentile for age), and her height was 158 cm (~ 50th percentile). Figures 1 and 2 are images from her abdominal computed tomographic (CT) scan.