Volume 7 Supplement 1
Accuracy of ultrasonography for the diagnosis of pneumoperitoneum
© Nazerian et al; licensee Springer. 2015
Published: 9 March 2015
Clinical signs and symptoms of pneumoperitoneum are not specific and abdomen radiography is positive in less than 50% of cases. Ultrasonography (US) accuracy for the diagnosis of pneuperitoneum is still unknown.
1) define the accuracy of abdominal US for the diagnosis of pneumoperitoneum; 2) define the accuracy of a “2 scan-fast exam” vs a full abdominal exam; 3) compare accuracy of US and abdomen radiography
Patients and methods
Study patients: 11 consecutive adults with a diagnosis of pneumoperitoneum by CT. Control patients: 11 consecutive adults with severe acute abdominal pain with a diagnosis other than pneumoperitoneum by CT. US examination has been performed with a convex and a linear probe using the following scans: epigastrium, right and left hypocondrium, umbelical area and right hypocondrium. All exams were recorded in a video of 5 seconds and each videos reviewed by 2 radiologists and 2 senior physicians blinded to other imaging studies. The reviewers fulfilled a standardized form signing for each scan either presence or absence of pneumoperitonem signs (enhancement of the peritoneum stripe with ring-down artifacts or “comet tails” starting from peritoneum). If one of the signs of pneumopeitoneum was present in at least one scan, the patient was considered to have a US diagnosis of pneumoperitoneum. The reviewers also evaluated abdomen radiography for the presence/absence of pneumoperitoneum. CT was considered the gold standard.
1) Accuracy of abdomen US was 88.6%. Sensitivities of convex and linear probes were similar (88.6% vs 84.1%), while specificity of convex was lower than linear probe (81.8% vs 95.5%). 2) Accuracy of a “2 scan-fast exam” was similar to global exam (87.5%). 3) Abdominal radiography sensitivity (72.2%) was lower than US while specificity (92.5%) was higher.
Abdominal US has a good accuracy. The 2 scan-fast exam has a similar accuracy of the full abdominal exam. US sensitivity is superior to abdominal radiography thus ultrasonography can be a useful imaging modality for the detection of pneumoperitoneum.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.