MDCT angiography in abdominal aortic aneurysm treated with endovascular repair: diagnostic impact of slice thickness on detection of endoleaks.

Abstract

The objective of our study was to evaluate the diagnostic impact of slice thickness on the detection of endoleaks at MDCT. Fifty patients with abdominal aortic aneurysm treated with endovascular repair who had undergone follow-up MDCT were enrolled in this study. Contrast-enhanced images were obtained with a 4-MDCT scanner (1-mm collimation). Images were reconstructed using a 1-mm (set A), 3-mm (set B), or 5-mm (set C) slice width. Each image set was interpreted by two independent readers for the presence of endoleaks and for image quality on a dedicated workstation. Sensitivity, specificity, and positive predictive values of each reading session were compared. The statistical values obtained with sets A and B were significantly higher (p < 0.001) than those obtained with set C. No statistically significant differences were found between the values obtained with sets A and B. For the detection of endoleaks at MDCT, the sensitivity of 1- and 3-mm-thick images was significantly higher than that of 5-mm-thick slices. However, no statistically significant differences were found between the 1- and 3-mm image sets; moreover, the use of thinner reconstruction images (1 mm) has the disadvantage of increasing the number of images that must be interpreted and archived.