Computed tomography of bowel obstructions: The contribution of multiplanar reformations in comparison with axial slices alone in determining the transition zone

Abstract

Several studies have demonstrated that determining the transition zone could facilitatethe diagnosis of bowel obstruction (BO) using multi-detector row computedtomography (MDCT). We aimed to evaluate the contribution of multi-planarreformations (MPR) in comparison with axial slices alone to determine thetransition zone. Sixteen-slice MDCT examinations of 66 consecutive patientswith mechanical BO were reviewed by an experienced abdominal radiologistwho had been blinded to the patients’ clinical diagnoses. The scans were firstreviewed using the axial slices alone and later were reviewed using MPR withrespect to the assigned four-point confidence scale in a random order. The diagnosticaccuracy and mean confidence score were evaluated for both reviewingmethods. The accuracy for determining the transition zone using axial slicesalone was 92% in patients with small bowel obstruction (SBO) and 93% inthose with large bowel obstruction (LBO). The levels of accuracy for MPR wereexactly the same with axial slices alone both for SBO and LBO. The meanconfidence score for the determination of the transition zone using axial slicesalone was 3.59 for SBO and 3.71 for MPR (P=0.057). After evaluating patientswith LBO, the mean confidence score using axial slices alone was 3.80, whichwas identical to that of MPR. Like MPR, axial CT source slices can also providehigh levels of accuracy in the determination of the transition zone in patientswith BO. However, particularly in SBO, MPR will increase confidence in thediagnosis.