The initial examination is a plain film of the abdomen. If pain is apparently related to a specific upper abdominal organ (liver, GB, kidney) the next step is an ultrasound of the abdomen. If pain is less specific or not apparently organ-specific, an UGI series is suggested for the evaluation of peptic acid disease. If these steps are inconclusive, then a CT scan of the abdomen with oral and IV contrast should also usually be requested. Please note that acute evaluation of the pancreas is frequently more effectively accomplished by skipping US and going straight to CT with pancreatic protocol.