Contrast-enhanced ultrasonography with Sonazoid™ for the evaluation of bowel ischemia

Purpose To determine the usefulness of contrast-enhanced ultrasonography with the contrast agent Sonazoid™ for the detection of bowel ischemia. Methods From March 2007 to February 2009, 65 patients (35 men and 30 women, mean age 70.4 ± 16.1 years) were enrolled. Fifty-three patients complained of acute abdominal pain with small bowel dilatation ( n = 40) or reduced bowel peristalsis ( n = 13). Twelve patients were clinically suspected of having bowel ischemia. After Sonazoid™ injection, bowel segments were scanned using harmonic imaging, and the signal intensities were classified as normal or diminished. The definitive diagnosis was confirmed by surgery in 30 patients, autopsy in 6, endoscopy in 3, angiography in 1, and clinical follow-up in 25. Results All 50 patients with normal signal intensities were confirmed not to have bowel ischemia. In the 15 patients with diminished signal intensities, 14 patients were confirmed to have bowel ischemia, resulting in an overall sensitivity of 100% [95% confidence interval (CI) 80.7–100%], a specificity of 98% [95% CI 89.5–99.9%], a positive predictive value of 93% (95% CI 68.1–99.8%), and a negative predictive value of 100% (95% CI 94.1–100%). Conclusion Contrast-enhanced ultrasonography with Sonazoid™ is a highly sensitive and specific method for the diagnosis of bowel ischemia.