To identify thecauses of the acute non-surgical abdomen and recognize them on different imaging modalities to guide correct management of patients.

Acute abdominal pain is one of the most common presentations to the emergency department. Undifferentiated abdominal pain can be either surgical or non-surgical in aetiology and present a diagnostic challenge to the clinician. Correct diagnosis not only saves time and resources, it also prevents the patient from having an unnecessary surgical procedure which may result in prolonged hospital stay and increased morbidity. Aetiology can be divided into body systems: Gastrointestinal pancreatitis, diverticulitis, inflammation of the GI tract ("-itis"), hepatitis, inflammatory bowel disease, pyelonephritis, acute appendagitis,...

Gastrointestinal: Pancreatitis - acute inflammation of the pancreas. Can be interstitial oedematous pancreatitis (IOP) or necrotizing pancreatitis (NP). In IOP (Fig. 1), computed tomography (CT) typically shows enlarged and oedematous pancreas with loss of normal fat lobulation. Peri-pancreatic oedema, free fluid and fat stranding are common. There is normal enhancement of parenchyma without necrosis. CT of NP (Fig. 2) demonstrates greater degree of peri-pancreatic free fluid and inflammation than IOP. Necrosis can develop days after initial presentation. Diverticulitis - pericolonic and intramural inflammatory process secondary...

Acute abdominal pain can have many non-surgical causes. As a radiologist or clinician, it is important to recognize and identify them on various imaging modalities. This enables accurate and timely diagnosis which then facilitates correct management of the patient.

Dr. Wei-Che Tsai Radiology registrar (year 2) Royal Hobart Hospital Tasmania Dr. Aditya Varma Consultant radiologist Royal Hobart Hospital Tasmania

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