Role of Extracranial Carotid Duplex and Computed Tomography Perfusion Scanning in Evaluating Perfusion Status of Pericarotid Stenting.
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ABSTRACT:
SUBMITTER: Lin CM
PROVIDER: S-EPMC4802025 | biostudies-literature | 2016
REPOSITORIES: biostudies-literature
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Role of Extracranial Carotid Duplex and Computed Tomography Perfusion Scanning in Evaluating Perfusion Status of Pericarotid Stenting.
Lin Chih-Ming CM Chang Yu-Jun YJ Liu Chi-Kuang CK Yu Cheng-Sheng CS Lu Henry Horng-Shing HH
BioMed research international 20160308
Carotid stenting is an effective treatment of choice in terms of treating ischemic stroke patients with concomitant carotid stenosis. Though computed tomography perfusion scan has been recognized as a standard tool to monitor/follow up this group of patients, not everyone could endure due to underlying medical illness. In contrast, carotid duplex is a noninvasive assessment tool and could track patient clinical condition in real time. In this study we found that "resistance index" of the carotid ...[more]
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Project description:Novel biomarkers are advocated to manage carotid plaques. Therefore, we aimed to test the association between textural features of carotid plaque at computed tomography angiography (CTA) and unfavorable outcome after carotid artery stenting (CAS). Between January 2010 and January 2021, were selected 172 patients (median age, 77 years; 112/172, 65% men) who underwent CAS with CTA of the supra-aortic vessels performed within prior 6 months. Standard descriptors of the density histogram were derived by open-source software automated analysis obtained by CTA plaque segmentation. Multiple logistic regression analysis, receiver operating characteristic (ROC) curve analysis and the area under the ROC (AUC) were used to identify potential prognostic variables and to assess the model performance for predicting unfavorable outcome (periprocedural death or myocardial infarction and any ipsilateral acute neurological event). Unfavorable outcome occurred in 17/172 (10%) patients (median age, 79 years; 12/17, 70% men). Kurtosis was an independent predictor of unfavorable outcome (odds ratio, 0.79; confidence interval, 0.65-0.97; p = 0.029). The predictive model for unfavorable outcome including CTA textural features outperformed the model without textural features (AUC 0.789 vs. 0.695, p = 0.004). In patients with stenotic carotid plaque, kurtosis derived by CTA density histogram analysis is an independent predictor of unfavorable outcome after CAS.
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Project description:BackgroundThe clinical treatment of patients with severe diabetic foot (DF) is difficult. Recently, the First Affiliated Hospital of Guangxi Medical University began to apply tibial transverse transport (TTT) in patients with DF. This treatment has achieved significant effects, but its mechanism of action is unclear. Recently, microcirculation and the pathogenesis of diabetes have become the foci of research in this field. The evaluation of the possible mechanism of microcirculation reconstruction requires relevant indicators. The aim of this study was to investigate the value of computed tomography perfusion in evaluations of the curative effects of TTT and establish corresponding quantitative evaluation indicators.MethodsTwelve patients with DF treated with TTT were recruited as the research participants. All diabetic feet were divided into the transport foot (TF) group and nontransport foot (NTF) group according to whether the patients underwent TTT. All patients underwent CT shuttle scanning preoperatively and 8 weeks after surgery. The shuttle scan data were transferred to Siemens VPCT body software and postprocessed with Customized Tumor2. We chose the TF posterior tibial artery from a distance of approximately 15 cm to the bifurcation of the plantar medial artery and the lateral plantar artery as the input artery. We selected the centre of the bilateral medial plantar muscle group on the coronal and axial regions of interest. We applied a deconvolution approach to obtain data from both sides of the plantar tissue perfusion. Skin temperature (ST) detection was performed with an ST gun to measure the average ST values in the dorsal and plantar areas, the first and fifth heads of the phalanges, and the medial and lateral malleolus points of both feet of patients with DF preoperatively and 8 weeks after surgery.ResultsThe preoperative and postoperative ST values of the patients in the TF group were 30.73 ± 1.86 °C and 32.22 ± 1.51 °C, respectively. The preoperative and postoperative ST values for the patients in the NTF group were 30.93 ± 2.65 °C and 32.07 ± 2.09 °C, respectively. There were significant differences in the preoperative and postoperative data between the TF (P = 0.001) and NTF (P = 0.013) groups. In the patients with DF who underwent TTT, there were both preoperative and postoperative differences inside the medial plantar muscle group in the relative blood volume (rBV) value and relative mean transit time (rMTT) (P = 0.027, P = 0.026, respectively). The postoperative BV in the NTF group was increased compared with the preoperative BV (P = 0.006).ConclusionThere were significant differences in relative BV, relative mean transit time, and ST between the two groups before and after surgery, and the postoperative BV in the NTF group and ST values in the two groups were increased compared with the preoperative values. The BV in the NTF group and the ST values in the two groups were effective indicators in evaluating the changes between preoperative and postoperative perfusion. These results indicate that TTT could increase plantar tissue perfusion as assessed by BV and ST; this increase was among the reasons for the surface healing of severe DF ulcers.Translational potential of this articlePreoperative CT perfusion evaluation can provide relevant information of blood vessels and microcirculation for clinical operation, and postoperative CT perfusion evaluation can provide postoperative efficacy evaluation for clinical operation. All patients received information about the study and signed a specific informed consent. Approval for this study was granted by the regional ethics committee [Regional Ethics Committee of the First Affiliated Hospital of Guangxi Medical University, China [(2018-(KY-E-069].
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