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Purpose: We aimed to evaluate the effectiveness of the endourologic management of forgotten and/or encrusted ureteral stents together with our single-center experience.

Materials and methods: Fifty-four patients with forgotten double-J ureteral stents were treated in our center between January 2008 and March 2014. Encrustation and the related stone burdens were estimated by using computerized tomography and kidney–ureter–bladder radiography. The management method was chosen based on the stone burden or clinical and radiological findings.

Results: Fifty-four patients, 39 males and 15 females, were included in the study. The average age of the patients was 38.2?±?25.06 (2–86) years. The average indwelling time of the ureteral stents was 22.6?±?30.3 (6–144) months. Six of the patients with forgotten stents had solitary kidneys. The double-J stent (DJS) was fragmented in four (7.4%) patients. A urinary system infection was present in 15 (27.7%) of the patients. The ureteral stents and related stones were successfully removed without any complications by combined endourologic techniques to achieve a stone-free state in all patients except for patient with 110 months of forgotten stent time in whom nephrectomy was performed for a nonfunctioning kidney related to the forgotten stent.

Conclusions: Forgotten/encrusted DJS may lead to complications in a range of urinary system infections, up to a loss of renal function. They can be safely and successfully removed, and the renal function can be preserved by endourologic techniques, starting with the least invasive procedures in centers highly experienced.  相似文献   
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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.
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The aim of this study is to report clinical and imaging findings, and treatment outcomes of a patient with nodular posterior scleritis. A 41-year-old woman was diagnosed as nodular posterior scleritis in the light of clinical and imaging findings. At first admission best corrected visual acuity was 20/50 in her right eye. Fundus examination revealed an amelanotic subretinal mass under the superior temporal arcade associated with subretinal fluid surrounding it. B-scan ultrasonography, optical coherence tomography, fluorescein angiography, and indocyanine green angiography findings confirmed the diagnosis. As treatment, nepafenac eye drops 3 times a day, and flurbiprofen tablet 100 mg twice a day were prescribed. After 4 weeks of treatment, the ocular pain was relieved, BCVA improved to 20/20, and subretinal mass totally regressed. Although the diagnosis of nodular posterior scleritis may be confusing, it has to be kept in mind in patients with a subretinal/choroidal mass. Multimodal fundus imaging may be helpful in differential diagnosis. The condition is usually curable with non-steroidal anti-inflammatory drugs and/or systemic steroids.  相似文献   
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Purpose

Hypophysitis is a heterogeneous condition that includes inflammation of the pituitary gland and infundibulum, and it can cause symptoms related to mass effects and hormonal deficiencies. We aimed to evaluate the potential role of machine learning methods in differentiating hypophysitis from non-functioning pituitary adenomas.

Methods

The radiomic parameters obtained from T1A-C images were used. Among the radiomic parameters, parameters capable of distinguishing between hypophysitis and non-functioning pituitary adenomas were selected. In order to avoid the effects of confounding factors and to improve the performance of the classifiers, parameters with high correlation with each other were eliminated. Machine learning algorithms were performed with the combination of gray-level run-length matrix-low gray level run emphasis, gray-level co-occurrence matrix-correlation, and gray-level co-occurrence entropy.

Results

A total of 34 patients were included, 17 of whom had hypophysitis and 17 had non-functioning pituitary adenomas. Among the 38 radiomics parameters obtained from post-contrast T1-weighted images, 10 tissue features that could differentiate the lesions were selected. Machine learning algorithms were performed using three selected parameters; gray level run length matrix-low gray level run emphasis, gray-level co-occurrence matrix-correlation, and gray level co-occurrence entropy. Error matrices were calculated by using the machine learning algorithm and it was seen that support vector machines showed the best performance in distinguishing the two lesion types.

Conclusions

Our analysis reported that support vector machines showed the best performance in distinguishing hypophysitis from non-functioning pituitary adenomas, emphasizing the importance of machine learning in differentiating the two lesions.

  相似文献   
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OBJECTIVE: The purpose of this trial was to determine the spectrum of diseases with fever of unknown origin (FUO) in Turkey. METHODS: A prospective multicenter study of 154 patients with FUO in twelve Turkish tertiary-care hospitals was conducted. RESULTS: The mean age of the patients was 42+/-17 years (range 17-75). Fifty-three (34.4%) had infectious diseases (ID), 47 (30.5%) had non-infectious inflammatory diseases (NIID), 22 (14.3%) had malignant diseases (MD), and eight (5.2%) had miscellaneous diseases (Mi). In 24 (15.6%) of the cases, the reason for high fever could not be determined despite intensive efforts. The most common ID etiologies were tuberculosis (13.6%) and cytomegalovirus (CMV) infection (3.2%). Adult Still's disease was the most common NIID (13.6%) and hematological malignancy was the most common MD (7.8%). In patients with NIID, the mean duration of reaching a definite diagnosis (37+/-23 days) was significantly longer compared to the patients with ID (25+/-12 days) (p=0.007). In patients with MD, the mean duration of fever (51+/-35 days) was longer compared to patients with ID (37+/-38 days) (p=0.052). CONCLUSIONS: Although infection remains the most common cause of FUO, with the highest percentage for tuberculosis, non-infectious etiologies seem to have increased when compared with previous studies.  相似文献   
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