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361.
Nyman HT Nielsen OL McEvoy FJ Lee MH Martinussen T Hellmén E Kristensen AT 《American journal of veterinary research》2006,67(6):985-991
OBJECTIVE: To compare and correlate B-mode and color Doppler ultrasonographic characteristics with the histologic findings of benign and malignant mammary tumors in dogs. STUDY POPULATION: 49 mammary tumors in 26 dogs. PROCEDURES: Before excision, tumors were evaluated via B-mode and color Doppler ultrasonography to assess size, echogenicity, echopattern, acoustic transmission, invasiveness, and vascularity. Paraffin-embedded microsections of the tumors were stained with H&E and examined for presence of necrosis, cysts, cartilage, bone, mineralization, invasion of surrounding tissue, and tissue heterogeneity. To assess vascularity, the number and distribution of vessels that were stained by the Verhoeff van Gieson technique were recorded. RESULTS: Tumor echogenicity and echopattern on ultrasonographic images correlated with tissue heterogeneity detected histologically. Acoustic enhancement was correlated with the presence of necrotic or cystic areas. Tumor invasion into surrounding tissues as determined ultrasonographically did not correlate with the histologic findings. There was a significant correlation between the number of detected vessels and distribution of flow within the tumors determined via ultrasonographic and histologic examinations. CONCLUSIONS AND CLINICAL RELEVANCE: In canine mammary tumors, ultrasonographic characteristics appear to be correlated with histopathologic changes. Data suggest that ultrasonography may have an important role in the evaluation of mammary tumors in dogs, particularly in the evaluation of tissue composition and tumor vascularity. 相似文献
362.
Pulmonary vasculature in dogs assessed by three‐dimensional fractal analysis and chemometrics
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Anna V. Müller Clara B. Marschner Annemarie T. Kristensen Bo Wiinberg Amy F. Sato Jose M. A. Rubio Fintan J. McEvoy 《Veterinary radiology & ultrasound》2017,58(6):653-663
Fractal analysis of canine pulmonary vessels could allow quantification of their space‐filling properties. Aims of this prospective, analytical, cross‐sectional study were to describe methods for reconstructing three dimensional pulmonary arterial vascular trees from computed tomographic pulmonary angiogram, applying fractal analyses of these vascular trees in dogs with and without diseases that are known to predispose to thromboembolism, and testing the hypothesis that diseased dogs would have a different fractal dimension than healthy dogs. A total of 34 dogs were sampled. Based on computed tomographic pulmonary angiograms findings, dogs were divided in three groups: diseased with pulmonary thromboembolism (n = 7), diseased but without pulmonary thromboembolism (n = 21), and healthy (n = 6). An observer who was aware of group status created three‐dimensional pulmonary artery vascular trees for each dog using a semiautomated segmentation technique. Vascular three‐dimensional reconstructions were then evaluated using fractal analysis. Fractal dimensions were analyzed, by group, using analysis of variance and principal component analysis. Fractal dimensions were significantly different among the three groups taken together (P = 0.001), but not between the diseased dogs alone (P = 0.203). The principal component analysis showed a tendency of separation between healthy control and diseased groups, but not between groups of dogs with and without pulmonary thromboembolism. Findings indicated that computed tomographic pulmonary angiogram images can be used to reconstruct three‐dimensional pulmonary arterial vascular trees in dogs and that fractal analysis of these three‐dimensional vascular trees is a feasible method for quantifying the spatial relationships of pulmonary arteries. These methods could be applied in further research studies on pulmonary and vascular diseases in dogs. 相似文献