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31.

Purpose

To evaluate the relationship between fractional flow reserve (FFR)-determined coronary artery stenosis severity and myocardial perfusion parameters derived from dynamic myocardial CT perfusion imaging (CTP) in an ex-vivo porcine heart model.

Methods

Six porcine hearts were perfused according to Langendorff. Circulatory parameters such as arterial blood flow (ABF) (L/min), mean arterial pressure (MAP) (mmHg) and heart rate (bpm) were monitored. Using an inflatable cuff and monitored via a pressure wire, coronary artery stenoses of different FFR grades were created (no stenosis, FFR = 0.80, FFR = 0.70, FFR = 0.60, and FFR = 0.50). Third generation dual-source CT was used to perform dynamic CTP in shuttle mode at 70 kV. Using the AHA-16-segment model, myocardial blood flow (MBF) (mL/100 mL/min) and volume (MBV) (mL/100 mL) were analyzed using dedicated software for all ischaemic and non-ischaemic segments.

Results

During five successful experiments, ABF ranged from 0.8 to 1.2 L/min, MAP from 73 to 90 mmHg and heart rate from 83 to 115 bpm. Non-ischaemic and ischaemic segments showed significant differences in MBF for stenosis grades of FFR ≤ 0.70. At this degree of obstruction, median MBF was 79 (interquartile range [IQR]: 66–90) for non-ischaemic segments versus 56 mL/100 mL/min (IQR: 46–73) for ischaemic segments (p < 0.05). For MBV, a significant difference was found at FFR ≤ 0.80 with median MBV values of 7.6 (IQR: 7.0–8.3) and 7.1 mL/100 mL (IQR: 6.0–8.2) for non-ischaemic and ischaemic myocardial segments, respectively (p < 0.05).

Conclusion

Artificial flow alterations in a Langendorff porcine heart model could be detected and measured by CTP-derived myocardial perfusion parameters and showed significant systematic correlation with stepwise flow reduction that permitted early detection of ischaemic myocardium. Additional research in clinical setting is required to develop absolute quantitative CTP.  相似文献   
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BackgroundTo develop and validate a contrast-enhanced CT based classification tree model for classifying solid lung tumors in clinical patients into malignant or benign.MethodsBetween January 2015 and October 2017, 827 pathologically confirmed solid lung tumors (487 malignant, 340 benign; median size, 27.0 mm, IQR 18.0–39.0 mm) from 827 patients from a dedicated Chinese cancer hospital were identified. Nodules were divided randomly into two groups, a training group (575 cases) and a testing group (252 cases). CT characteristics were collected by two radiologists, and analyzed using a classification and regression tree (CART) model. For validation, we used the decision analysis threshold to evaluate the classification performance of the CART model and radiologist’s diagnosis (benign; malignant) in the testing group.ResultsThree out of 19 characteristics [margin (smooth; slightly lobulated/lobulated/spiculated), and shape (round/oval; irregular), subjective enhancement (no/uniform enhancement; heterogeneous enhancement)] were automatically generated by the CART model for classifying solid lung tumors. The sensitivity, specificity, PPV, NPV, and diagnostic accuracy of the CART model is 98.5%, 58.1%, 80.6%, 98.6%, 79.8%, and 90.4%, 54.7%, 82.4% 98.5%, 74.2% for the radiologist’s diagnosis by using three-threshold decision analysis.ConclusionsTumor margin and shape, and subjective tumor enhancement were the most important CT characteristics in the CART model for classifying solid lung tumors as malignant. The CART model had higher discriminatory power than radiologist’s diagnosis. The CART model could help radiologists making recommendations regarding follow-up or surgery in clinical patients with a solid lung tumor.  相似文献   
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We determined the efficiency of a screening protocol based on coronary calcium scores (CCS) compared with exercise testing in patients with suspected coronary artery disease (CAD), a normal ECG and troponin levels. Three-hundred-and-four patients were enrolled in a screening protocol including CCS by electron beam computed tomography (Agatston score), and exercise testing. Decision-making was based on CCS. When CCS≥400, coronary angiography (CAG) was recommended. When CCS<10, patients were discharged. Exercise tests were graded as positive, negative or nondiagnostic. The combined endpoint was defined as coronary event or obstructive CAD at CAG. During 12±4 months, CCS≥400, 10–399 and <10 were found in 42, 103 and 159 patients and the combined endpoint occurred in 24 (57%), 14 (14%) and 0 patients (0%), respectively. In 22 patients (7%), myocardial perfusion scintigraphy was performed instead of exercise testing due to the inability to perform an exercise test. A positive, nondiagnostic and negative exercise test result was found in 37, 76 and 191 patients, and the combined endpoint occurred in 11 (30%), 15 (20%) and 12 patients (6%), respectively. Receiver-operator characteristics analysis showed that the area under the curve of 0.89 (95% CI: 0.85–0.93) for CCS was superior to 0.69 (95% CI: 0.61–0.78) for exercise testing (P<0.0001). In conclusion, measurement of CCS is an appropriate initial screening test in a well-defined low-risk population with suspected CAD.  相似文献   
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Few clinical trials address efficacy of adjuvant systemic treatment in patients with in-transit melanoma (ITM). This study describes adjuvant systemic therapy of ITM patients beyond clinical trials. In this study, we included stage III adjuvant-treated melanoma patients registered in the nationwide Dutch Melanoma Treatment Registry between July 2018 and December 2020. Patients were divided into three groups: nodal disease only, ITM only and ITM and nodal disease. Recurrence patterns, recurrence-free survival (RFS) and overall survival (OS) at 12-months were analyzed. In our study population of 1037 patients, 66.8% had nodal disease only, 16.7% had ITM only and 16.2% had ITM with nodal disease. RFS at 12-months was comparable in the nodal only and ITM only group (72.2% vs70.1%, P = .97) but lower in ITM and nodal disease patients (57.8%; P = .01, P < .01). Locoregional metastases occurred as first recurrence in 38.9% nodal disease only, 71.9% of ITM-only and 44.0% of ITM and nodal disease patients. Distant recurrences occurred in 42.3%, 18.8% and 36.0%, respectively (P = .02). 12-months OS was not significantly different for nodal disease only patients compared with ITM-only (94.4% vs 97.6%, P = .06) but was significantly higher for ITM-only compared with ITM and nodal disease patients (97.6% vs 91.0%, P < .01). In conclusion, we showed that in the adjuvant setting, RFS rates in ITM-only patients are similar to non-ITM, though better than in ITM and nodal disease patients. Adjuvant-treated ITM-only patients less often experience distant recurrences and have a superior OS compared with ITM and nodal disease patients.  相似文献   
37.
Prevention Science - This study evaluates the effectiveness of the KiVa antibullying program in the Netherlands through a randomized controlled trial of students in grades 3–4 (Dutch grades...  相似文献   
38.
BackgroundLow-dose computed tomography (LDCT) lung cancer screening often refers individuals to unnecessary examinations. This study aims to compare the European Position Statement (EUPS) and National Comprehensive Cancer Network (NCCN) protocols in management of participants at baseline screening round.MethodsLDCT lung cancer screening was prospectively performed in a Chinese asymptomatic population aged 40–74 years. A total of 1,000 consecutive baseline LDCT scans were read twice independently. All screen-detected lung nodules by the first reader were included. The first reader manually measured the diameter of lung nodules (NCCN protocol), and the second reader semi-automatically measured the volume and diameter (EUPS volume and diameter protocols). The protocols were used to classify the participants into three management groups: next screening round, short-term repeat LDCT scan and referral to a pulmonologist. Groups were compared using Wilcoxon test for paired samples. Number of lung cancers by protocols was provided.ResultsOf the 1,000 participants (61.4±6.7 years old), 168 lung nodules in 124 participants were visually detected and manually measured in the first reading, and re-measured semi-automatically. Applying the NCCN protocol, EUPS volume and diameter protocol, the proportion of referrals among all participants was 0.6%, 1.9%, and 1.4%, respectively. The proportion of short-term repeat scans was 4.5%, 9.7% and 4.5%, respectively. Among the 10 lung cancer patients, one would have been diagnosed earlier if the EUPS volume protocol would have been followed.ConclusionsIn a first round screening in a Chinese general population, the lower threshold for referral in the EUPS protocol as compared to the NCCN protocol, leads to more referrals to a pulmonologist, with the potential of earlier cancer diagnosis. The EUPS volume protocol recommends fewer participants to short-term repeat LDCT scan than the EUPS diameter protocol. Follow-up studies should show the impact of both protocols on (interval) cancer diagnosis.  相似文献   
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This article describes an incision which incorporates principles of both the Bunnell midlateral incision and the Bruner zig-zag. It allows rapid access to the volar aspect of the digit without sacrificing exposure or risking flexion contractures while maintaining an unviolated volar skin flap. In this study of 125 patients, 189 digital problems were treated, using the modified midlateral incision. Ages ranged from eleven months to seventy-one years. Complications following surgery were unrelated to the incision.  相似文献   
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