Missed Ischaemia in adult bowel obstruction: CT Fails to safely exclude Ischaemia – A systematic review and diagnostic meta-analysis

Published Date: 01st September 2026

Publication Authors: Abdulmajed. MI

Purpose
The role of MIS in elective surgery is fully recognised and established but there is still a general reluctance to incorporate MIS techniques in emergency surgery. The recent NELA data review showed only 14.6% of the cases were approached laparoscopically where half of all cases were converted to open. This study was looking at whether the MIS approach beyond laparoscopic appendectomy and cholecystectomy for NELA eligible cases is safe and feasible.

Methods
Systematic review and random-effects diagnostic meta-analysis of adult randomised controlled trials, cohort studies, and case–control studies evaluating CT for bowel obstruction and ischaemia. MEDLINE and Embase were searched from 1946 to February 2025. Three reviewers independently extracted data and assessed the risk of bias using QUADAS-2. Heterogeneity was summarised using I2 and Tau2..

Results
Sixty-five studies (9418 patients) were included. CT demonstrated high accuracy for diagnosing bowel obstruction (pooled sensitivity 90.0% [95% CI 78–96]; specificity 88.8% [95% CI 78.0–94.8]). However, CT sensitivity for bowel ischaemia was only 47.0% (95% CI 32.4–59.9) with a specificity of 85.3% (95% CI 77.9–89.5). This corresponds to approximately one in two cases of bowel ischaemia missed by CT. Multidetector CT (MDCT) outperformed older modalities across all outcomes. Ischaemia occurred in 22.05% of all cases and was more frequent in small bowel obstruction. Perforation and mortality rates were 3.98% and 4.4%, respectively.

Conclusion
CT reliably confirms bowel obstruction in adults but cannot safely exclude ischaemia. Negative CT findings should not reassure when clinical concern persists. Escalation, reassessment, or repeat imaging are therefore warranted despite an apparently reassuring scan to reduce the risk of missed ischaemia.

Ahmad, SJS; Abdulmajed, MI et al. (2026). O23 Missed Ischaemia in adult bowel obstruction: CT Fails to safely exclude Ischaemia – A systematic review and diagnostic meta-analysis. Colorectal Disease. 28(S1), p.e70581. [Online]. Available at: https://dx.doi.org/10.1111/codi.70581 [Accessed 15 October 2026]