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951.

Purpose  

To analyze tangential wedged beam and field-in-field (FIF) technique doses using dose-volume histograms and conformality indices for target volume and healthy tissues within the irradiated volume.  相似文献   
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BackroundWe aimed to evaluate the utility of the preprocedural platelet–lymphocyte ratio (PLR) for predicting the no‐reflow phenomenon after thrombus aspiration during percutaneous coronary intervention (PCI) in patients with ST‐segment elevation myocardial infarction (STEMI).MethodWe retrospectively analyzed postprocedural thrombolysis in myocardial infarction (TIMI) flow grades and myocardial blush grades (MBG) of 247 patients who underwent a PCI procedure with thrombus aspiration.We divided these patients into two groups according to whether they had no‐reflow (TIMI < 3, MBG < 2) or not (TIMI 3, MBG ≥ 2).ResultsNo‐reflow developed in 43 (17%) patients.Preprocedural PLR was significantly higher in the no‐reflow group (183.76 ± 56.65 vs 118.32 ± 50.42 p < 0.001).Independent predictors of no‐reflow were as follows: higher preprocedural platelet‐lymphocyte ratio (PLR) (OR = 1.018; 95% CI = 1.004, 1.033; p = 0.013),mean corpuscular volume (MCV) (OR = 1.118; 95% CI = 1.024, 1.220; p = 0.012) and SYNTAX Score‐2 (OR = 1.073; 95% CI = 1.005, 1.146; p = 0.036). PLR of 144 had 79% sensitivity and 75% specificity for the prediction of no‐reflow.ConclusionPLR is a reliable predictor for no‐reflow in STEMI patients undergoing thrombus aspiration.  相似文献   
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Mallet fractures are avulsion fractures of the extensor tendon from the distal phalanx base and often occur due to sudden flexion or axial loading. In this study, we aimed to compare the clinical and radiological results of patients treated with single and double dorsal wires from the dorsal in the extension block method.Patients to whom a single wire from dorsal was applied were assigned to Group 1 (n: 22), and those to whom double wires were applied were assigned to Group 2 (n: 23). Surgical treatment was decided for patients with more than 1/3 of the fracture fragment containing the joint surface and volar subluxation. The range of motion of the distal interphalangeal (DIP) joint was measured with a goniometer. The displacement of the fragment was measured before and after surgery on lateral radiographs. The presence of bridging callus formation on anterior-posterior and lateral radiographs was evaluated for a union.There were 30 male (66.7%) and 15 (33.3%) female patients. The mean age of the patients was 32 years. Radiographic union was obtained in all patients. Pseudoarthrosis was not observed in any patient. The Crawford score was excellent in 13 (28.9%) cases, the score was good in 18 (40%) cases, the scores were moderate in 13 (28.9%) cases, and the score was poor in 1 case (2.2%). There were no complications in 35 (77.8%) cases, dorsal bump complications occurred in 9 cases (20%), and osteoarthritis and dorsal bump complications occurred in 1 (2.2%) case. We did not observe nail deformity, skin necrosis, infection, or fingertip sensitivity. We found similar functional and clinical results between the groups.We recommend using single dorsal wire, as using double dorsal wires requires extra operation time, effort, and fluoroscopy.  相似文献   
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Myocardial fractional flow reserve (FFRmyo) has been demonstrated to be a useful method for determining the physiologic importance of a given coronary lesion. However, the reliability of the FFRmyo measurement is unknown in infarct-related arteries (IRA). The aim of this study was to measure and correlate the FFRmyo results of 14 consecutive patients who had recent acute myocardial infarction (AMI) (Group 1) with 14 consecutive patients who didnOt have AMI (Group 2) before and after percutaneous transluminal coronary angioplasty (PTCA). Quantitative coronary angiography (QCA) and FFRmyo measurements were determined both before and after optimal PTCA for all patients. FFRmyo was measured by use of a 0.014 inch guidewire as the ratio of the pressure distal to the target lesion to the aortic pressure taken during the maximal hyperemia induced by intracoronary adenosine. There were no differences between the two groups related to gender, target artery reference diameter, minimal luminal diameter and percent diameter stenosis of the vessel both before and after PTCA. While FFRmyo results after PTCA were not different between the groups, they were statistically different before PTCA (Group 1: 77.6+/-5.4%, Group 2: 63.3+/-8.4%; p<0.001). Although QCA-determined percent diameter stenosis revealed a significant degree of stenosis (66.5+/-10.5%) for Group 1, FFRmyo values were higher than 75% (77.6+/-5.4%), indicating insignificant stenosis. Thus, it was concluded that FFRmyo measurements before PTCA were significantly different between IRA and non-IRA and that the method may not be valid for the determination of stenosis significance in IRA.  相似文献   
958.
OBJECTIVE: Small-sized prosthetic valves used in aortic valve position usually cause a high transvalvular gradient. This situation, especially in people with a high body surface area, causes a patient-prosthetic valve mismatch. In this study, hemodynamic performances of the two new generation bileaflet, small size mechanical valves were evaluated during rest and stress conditions. METHODS: Eighteen patients with implanted 21-mm St. Jude HP (11 cases) and Sorin Bicarbon (7 cases) prosthetic valves in aortic position were evaluated at rest and during dobutamine infusion, 16.3+/-5.5 months after the operation. Dobutamine infusion was started at a dose of 5 microg/kg/min. The infusion rate was increased every 15 minutes up to 10-20-30 microg/kg/min. Maximum gradient, mean gradient, effective valve area (EVA), effective valve area index (EVAI) and performance index (PI) were calculated during rest and maximum dobutamine infusion rate. RESULTS: When the rest and dobutamine infusion measurements were compared, the maximum and mean gradients were found to be increased moderately, but EVA, EVAI, PI values did not change with increasing heart rates. For St. Jude valve; maximum gradient increased from 30.5+/-6.5 mmHg to 74.7+/-33.6 mmHg (p=0.03) and mean gradient increased from 17.9+/-3.8 to 40.8+/-23.8 mmHg (p=0.03). For Sorin Bicarbon valve; maximum gradient increased from 31.7+/-13.3 mmHg to 52.0+/-11.2 mmHg (p=0.01), mean gradient increased from 16.1+/-6.4 mmHg to 28.8+/-1.0 mmHg (p=0.01). The difference was not significant between the two valves with respect to measured parameters during rest and maximum dobutamine infusion. CONCLUSION: According to our findings, 21-mm Sorin Bicarbon and St. Jude HP mechanical bileaflet valves have good hemodynamic performance during exercise and these types of valves seem to be appropriate for patients with small aortic annulus.  相似文献   
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