Acute abdomen represents a spectrum of urgent clinical conditions requiring immediate and accurate diagnosis to guide timely surgical intervention. The role of imaging, particularly ultrasonography (USG) and computed tomography (CT) scan, has become increasingly critical in emergency settings. This prospective study aims to evaluate the diagnostic accuracy, time-efficiency, and clinical impact of USG and CT in patients presenting with acute abdominal pain. Conducted over 18 months, 150 patients aged between 18 and 70 years were included based on predefined clinical criteria. All patients underwent a preliminary clinical examination followed by USG; CT scans were performed where diagnosis remained inconclusive or where complications were suspected. Imaging findings were subsequently compared with intraoperative or final clinical diagnoses to calculate sensitivity, specificity, and overall diagnostic accuracy. The study revealed that USG successfully diagnosed 96 of 150 cases (64%) with a sensitivity of 71.4% and specificity of 83.3%. CT scan, on the other hand, confirmed or revised diagnoses in 135 patients (90%), showing a much higher sensitivity of 92.6% and specificity of 96.1%. CT scan was significantly more effective in diagnosing conditions such as hollow viscus perforation, appendicular abscess, intestinal obstruction, and mesenteric ischemia. USG remained the preferred modality in gallbladder diseases, gynecological emergencies, and in hemodynamically unstable patients due to its bedside availability. The average time to diagnosis using USG was approximately 25 minutes, while CT scan required around 70 minutes but offered detailed anatomical clarity. Importantly, CT findings influenced surgical decisions in over 67% of cases, either by confirming the initial diagnosis or altering the management plan. The study concludes that a stepwise imaging protocol beginning with USG, followed by CT in doubtful or critical cases, ensures both speed and diagnostic precision in managing acute abdomen. Timely use of imaging modalities not only improves diagnostic accuracy but also plays a decisive role in reducing morbidity, surgical complications, and overall hospital stay.

Acute abdomen, Ultrasonography, CT scan, Diagnostic accuracy, Emergency surgery, Imaging modalities, Surgical decision-making, Abdominal pain, Radiological evaluation, Emergency department.