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1.
Image quality in non‐contrast‐enhanced (NCE) angiograms is often limited by scan time constraints. An effective solution is to undersample angiographic acquisitions and to recover vessel images with penalized reconstructions. However, conventional methods leverage penalty terms with uniform spatial weighting, which typically yield insufficient suppression of aliasing interference and suboptimal blood/background contrast. Here we propose a two‐stage strategy where a tractographic segmentation is employed to auto‐extract vasculature maps from undersampled data. These maps are then used to incur spatially adaptive sparsity penalties on vascular and background regions. In vivo steady‐state free precession angiograms were acquired in the hand, lower leg and foot. Compared with regular non‐adaptive compressed sensing (CS) reconstructions (CSlow), the proposed strategy improves blood/background contrast by 71.3 ± 28.9% in the hand (mean ± s.d. across acceleration factors 1–8), 30.6 ± 11.3% in the lower leg and 28.1 ± 7.0% in the foot (signed‐rank test, P < 0.05 at each acceleration). The proposed targeted reconstruction can relax trade‐offs between image contrast, resolution and scan efficiency without compromising vessel depiction. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Objectives

Systemic sclerosis (SSc) is a chronic, inflammatory, and autoimmune connective tissue disease that is associated with vascular lesions, and fibrosis of the skin and visceral organs. Cardiac complications may occur as a secondary effect of SSc as a result of pulmonary arterial hypertension and interstitial lung disease. The objective of this study was to assess whether the pulmonary pulse transit time (pPTT) could serve as a diagnostic marker for pulmonary arterial alterations in patients with SSc, prior to development of pulmonary hypertension.

Methods

Twenty-five SSc patients as a study group and 25 age- and sex-matched healthy volunteers for the control group were recruited to the study. Right ventricle function parameters, such as tricuspid annular plane systolic excursion (TAPSE), estimated pulmonary artery systolic pressure (ePASP), right ventricular dimensions, right ventricle fractional area changes, and myocardial perfusion index (MPI) were measured and calculated. Pulmonary pulse transit time was defined as the time interval between the R-wave peak in the ECG and the corresponding peak late systolic pulmonary vein flow velocity.

Results

Right ventricle myocardial performance index (RVMPI) and eSPAP were significantly higher in the SSc group than the controls (p?=?0.032, p?=?0.012, respectively). Pulmonary pulse transit time and TAPSE was shorter in the patients with SSc (p?=?0.006, p?=?0.015, respectively). In correlation analysis, pPTT was inversely correlated with RVMPI (r?=???0.435, p?=?0.003), eSPAP (r?=???0.434, p?=?0.003), and disease duration (r?=???0.595, p?=?0.003). Conversely, it positively correlated with TAPSE (r?=?0.345, p?=?0.022).

Conclusion

pPTT was found to be shorter in SSc patients. pPTT might serve as a surrogate marker of pulmonary hemodynamics in patients with SSc, even prior to the development of pulmonary hypertension.
  相似文献   
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Background:

Some in vitro studies warn combining different metals in orthopedic surgery. The aim of this study is to determine the impact of combining titanium and stainless steel on bone healing and the clinical course of patients undergoing internal fixation of femoral fractures.

Materials and Methods:

69 patients with femoral fractures had polyaxial locking plate osteosynthesis. The locking plate was made of a titanium alloy. Two different cohorts were defined: (a) sole plating and (b) additional stainless steel cerclage wiring. Postoperative radiographs and clinical followup were performed at 6 weeks, 3 months and 12 months.

Results:

Cohorts A and B had 36 and 33 patients, respectively. Patient demographics and comorbidities were similar in both groups. In two cases in cohort A, surgical revision was necessary. No complication could be attributed to the combination of titanium and stainless steel.

Conclusion:

The combination of stainless steel cerclage wires and titanium plates does not compromise fracture healing or the postoperative clinical course.  相似文献   
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Background

The aim of this study was to compare the results of the single (STR) versus double TightRope? (DTR) technique for stabilisation of acute separations of the AC joint with the hypothesis that DTR achieves lower CC distance.

Patients and methods

A total of 29 consecutive patients treated operatively with the TR technique (mean age 38.1 years, n=26 male) were analysed in a cohort study with a mean follow-up of 13.3 months (12.0–21.7). Acute AC joint separations types III and V according to Rockwood (R) were included; R types I, II, IV and VI were excluded. The prospective scores determined pre-op and 3, 6 and 12 months post-op and X-rays were evaluated.

Results

Of the patients 12 suffered an R type III and 17 an R V separation; 14 were treated with STR and 15 with DTR. With STR, 8 R III and 6 R V injuries and with DTR 4 R III and 11 R V injuries were treated arthroscopically. STR achieved an increased CC distance >125% compared to the contralateral AC joint in five cases (36%). Two of them occurred as R V and three as R III injury. DTR achieved a CC distance >125% in two cases of an R V injury (13%).

Conclusion

The DTR technique provides lower CC distance compared to the STR technique, without a significant difference of CC distance and scores.  相似文献   
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Purpose

The absence of the umbilicus is, in essence, an aesthetic deformity of the abdominal wall. The goal of reconstructing the umbilicus is to obtain a natural, three-dimensional appearance. In this study, we present a new technique called the “dome procedure” for the reconstruction of the umbilicus.

Methods

This procedure can be applied under local anaesthesia on an outpatient basis and the drawing of the design is simple. The technique was applied to six patients who presented with an absence of the umbilicus following repair of a large incisional and umbilical hernia.

Results

No major or minor complications were encountered. Patient satisfaction was high after surgical intervention.

Conclusions

The dome procedure, which enables the umbilicus to have a natural appearance with sufficient depression and normal-appearing wrinkles, is simple, easy to perform, and safe.
  相似文献   
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