Browsing by Author "Ivanovic, A. (56803549500)"

Purpose: To estimate if CT perfusion parameter values of the esophageal cancer, which were obtained with the deconvolution-based software and maximum slope algorithm are in agreement, or at least interchangeable. Methods: 278 esophageal tumor ROIs, derived from 35 CT perfusion studies that were performed with a 64-MDCT, were analyzed. "Slice-by-slice" and average "whole-covered-tumor-volume" analysis was performed. Tumor blood flow and blood volume were manually calculated from the arterial tumortime- density graphs, according to the maximum slope methodology (BFms and BV ms), and compared with the corresponding perfusion values, which were automatically computed by commercial deconvolutionbased software (BF deconvolution and BVdeconvolution), for the same tumor ROIs. Statistical analysis was performed using Wilcoxon matched-pairs test, paired-samples t-test, Spearman and Pearson correlation coefficients, and Bland-Altman agreement plots. Results: BFdeconvolution (median: 74.75 ml/min/100 g, range, 18.00-230.5) significantly exceeded the BF ms(25.39 ml/min/100 g, range, 7.13-96.41) (Z = -14.390, p < 0.001), while BVdeconvolution (median: 5.70 ml/100 g, range: 2.10-15.90) descended the BVms(9.37 ml/100 g, range: 3.44-19.40) (Z = -13.868, p < 0.001). Both pairs of perfusion measurements significantly correlated with each other: BFdeconvolution, versus BFms (rS = 0.585, p < 0.001), and BVdeconvolution, versus BV ms (rS = 0.602, p < 0.001). Geometric mean BF deconvolution/BFms ratio was 2.8 (range, 1.1-6.8), while geometric mean BVdeconvolution/BVms ratio was 0.6 (range, 0.3-1.1), within 95% limits of agreement. Conclusions: Significantly different CT perfusion values of the esophageal cancer blood flow and blood volume were obtained by deconvolution-based and maximum slope-based algorithms, although they correlated significantly with each other. Two perfusion-measuring algorithms are not interchangeable because too wide ranges of the conversion factors were found. © 2013 Elsevier Ireland Ltd.

[No abstract available]

Background: The modern concept of type-related individualized groin hernia surgery imposes a demand for precise and accurate preoperative determination of the type of groin hernia. The aim of this prospective study was to evaluate the accuracy of ultrasonography in classification of groin hernias, according to the criteria of the unified classification system. Unified classification divides groin hernias into nine types (grades): type I (indirect, small), II (indirect, medium), III (indirect, large), IV (direct, small), V (direct, medium), VI (direct, large), VII (combined-pantaloon), VIII (femoral), and O (other). Patients and methods: One hundred and twenty-five adult patients with clinically diagnosed or suspected groin hernias were examined. Ultrasonography of both groins was performed with a 5 to 10-MHz linear-array transducer. Preoperative ultrasonographic findings of type of groin hernia were compared with the intraoperative findings, which were considered the gold standard. Results: Total accuracy of ultrasonography in determination of type of groin hernia was 96% (119 of 124 correct predictions of type of groin hernia compared with surgical explorations). All hernias of types I, IV, V, VII, and VIII were correctly identified with ultrasonography (sensitivity and specificity 100%). In the remaining five cases of the 124 (4%), hernia was incorrectly classified with ultrasonography: type VI (direct, large) was misdiagnosed as type III (indirect, large) in three cases, type III as type VI in one case, and type III as type II (indirect, medium) in one case. The sensitivity and the specificity of ultrasonography in classifying type II were 100 and 99%, respectively, for type III, 85 and 97%, and for type VI, 90 and 99%. Conclusion: Ultrasonography of the groin regions could be used with great accuracy for precise classification of groin hernias in adults. Each type of groin hernia, according to the unified classification system that we used for classification, has a characteristic ultrasonographic presentation, which is demonstrated in this study. © Springer-Verlag 2008.