Ultrasound Visceral Slide Assessment to Detect Adhesions in Patients Undergoing Abdominal Surgery – a Systematic Review and Meta-Analysis

Abstract

Study Objective To determine the diagnostic accuracy of preoperative visceral slide assessment with ultrasound to detect intra-abdominal adhesions, compared to the gold standard of intraoperative findings. Design Systematic review and meta-analysis, prospectively registered with the International Prospective Register of Systematic Reviews (PROSPERO). Setting Abdominal entry at time of laparoscopy is a critical step with risk of injury to underlying viscera due to bowel adhesions. Ultrasound can be used as a preoperative tool to assess slide of viscera underneath the abdominal wall in order to detect adhesion-free areas. Patients or Participants Prospective and cross-sectional studies in English that included patients at risk for adhesions, undergoing ultrasound visceral slide assessment followed by abdominal surgery. Interventions N/A Measurements and Main Results 3737 articles were screened through electronic searches of Cochrane, MEDLINE, EMBASE, and Google Scholar databases. Reference lists of relevant articles were searched for further articles. Two reviewers independently selected articles, extracted data, and assessed bias using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Primary authors were contacted for additional relevant data. Twenty-five articles reported on 1620 patients and 6166 assessed abdominal areas, with considerable heterogeneity of described abdominal areas and degrees of adhesions. Only 5 studies were performed blinded and 21 had high risk of selection bias. The periumbilical area was assessed for bowel adhesions in 869 patients in 11 studies, with 12.2% reported to have adhesions. Ultrasound assessment for periumbilical bowel adhesions had a combined sensitivity of 93.5% (95% confidence interval, 87.0-97.3), specificity of 91.7% (89.6-93.6), positive predictive value of 61.4% (55.5-66.9), and negative predictive value of 99.0% (98.0-99.5). Conclusion Visceral slide assessment with ultrasound has a high negative predictive value for absence of bowel adhesions in patients at risk for adhesions and should be considered as a useful tool to detect adhesion-free areas to assist with safe laparoscopic entry.