17th June 2021

A 28-year-old lady presents to the emergency department with severe right lower abdominal pain

A 28-year-old lady presents to the emergency department with severe right lower abdominal pain that started two hours ago. It has not been resolved with analgesics and there was an episode of nausea and vomiting. Her last menstrual period was 4 weeks ago. On physical examination, she appears uncomfortable and has rebound tenderness and guarding. No abdominal masses were identified, but pelvic examination found a right-sided adnexal mass. Her blood pressure is 102/60 mmHg, but she remains afebrile. Her urine pregnancy test was negative.

Select the SINGLE most appropriate radiological investigation from the list below. Select ONE option only.