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

OBJECTIVE: The objective of our study was to evaluate the diagnostic impact of slice thickness on the detection of endoleaks at MDCT.

SUBJECTS AND METHODS: 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.

RESULTS: 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.

CONCLUSION: 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.