ROLE OF X-RAYS AND ULTRASOUND IN DIAGNOSIS OF SMALL BOWEL OBSTRUCTION KEEPING CT-ABDOMEN AS GOLD STANDARD

Abstract

Background: Small bowel obstruction (SBO) represents a significant cause of acute abdominal emergencies, necessitating timely diagnosis to prevent complications such as bowel ischemia and perforation. Although CT abdomen remains the gold standard for diagnosing SBO due to its superior diagnostic precision, the accessibility and practicality of X-rays and ultrasound in initial assessments are particularly valuable in resource-limited settings. Comparative evaluation of these modalities is essential to optimize early detection strategies and improve clinical outcomes.

Objective: To evaluate the diagnostic efficacy of X-rays and ultrasound compared with CT abdomen, the gold standard, in the diagnosis of small bowel obstruction.

Methods: A prospective cohort study was conducted at the Department of Radiology, PAF Hospital Islamabad, from July 2024 to December 2024. A total of 175 patients presenting with clinical symptoms suggestive of SBO were enrolled using a non-probability convenient sampling technique. Patients underwent abdominal X-rays, ultrasound, and CT scans. CT abdomen served as the reference standard for calculating sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of X-rays and ultrasound. Data were analyzed using SPSS version 25.

Results: Compared to CT abdomen, ultrasound demonstrated a sensitivity of 93.7% (95% CI, 0.046–0.216, +OR 0.100) and a specificity of 81.0% (95% CI, 3.948–10.179, -OR 6.339), with a PPV of 56.8% and NPV of 31.8%. X-rays showed a sensitivity of 96.9% (95% CI, 0.016–0.144, +OR 0.047) and specificity of 87.0% (95% CI, 5.511–17.981, -OR 9.954), with a PPV of 58.0% and NPV of 31.0%.

Conclusion: X-rays demonstrated slightly higher diagnostic accuracy than ultrasound in detecting SBO, confirming their value as an initial screening tool in emergency settings. However, CT abdomen remains indispensable for definitive diagnosis and surgical decision-making.