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1.
目的:探讨SPECT/CT融合显像在评价下肢骨折远期愈合能力方面的价值。方法:回顾性分析59例下肢骨折患者术后6个月后的SPECT/CT融合图像,分析骨折愈合情况,并与随访或手术比较,计算SPECT/CT融合显像对下肢骨折远期愈合的诊断准确率。结果:59例常规影像学检查均不能判断是否具有远期愈合可能。SPECT/CT示51例放射性核素通过骨折线,提示具有远期愈合的可能;其中,44例随访X线显示愈合,7例手术治疗后X线片显示未愈合。8例SPECT/CT融合显像未见放射性核素通过骨折线,提示骨折不愈合,愈合可能性较小;经再次手术证实为骨折不愈合。SPECT/CT诊断骨折愈合的准确率为88.1%(52/59)。结论:SPECT/CT可较准确地评价骨折远期愈合情况,对临床具有很大的指导意义。  相似文献   
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ObjectivesThis study sought to describe worldwide variations in the use of myocardial perfusion imaging hardware, software, and imaging protocols and their impact on radiation effective dose (ED).BackgroundConcerns about long-term effects of ionizing radiation have prompted efforts to identify strategies for dose optimization in myocardial perfusion scintigraphy. Studies have increasingly shown opportunities for dose reduction using newer technologies and optimized protocols.MethodsData were submitted voluntarily to the INCAPS (International Atomic Energy Agency Nuclear Cardiology Protocols Study) registry, a multinational, cross-sectional study comprising 7,911 imaging studies from 308 labs in 65 countries. The study compared regional use of camera technologies, advanced post-processing software, and protocol characteristics and analyzed the influence of each factor on ED.ResultsCadmium-zinc-telluride and positron emission tomography (PET) cameras were used in 10% (regional range 0% to 26%) and 6% (regional range 0% to 17%) of studies worldwide. Attenuation correction was used in 26% of cases (range 10% to 57%), and advanced post-processing software was used in 38% of cases (range 26% to 64%). Stress-first single-photon emission computed tomography (SPECT) imaging comprised nearly 20% of cases from all world regions, except North America, where it was used in just 7% of cases. Factors associated with lower ED and odds ratio for achieving radiation dose ≤9 mSv included use of cadmium-zinc-telluride, PET, advanced post-processing software, and stress- or rest-only imaging. Overall, 39% of all studies (97% PET and 35% SPECT) were ≤9 mSv, while just 6% of all studies (32% PET and 4% SPECT) achieved a dose ≤3 mSv.ConclusionsNewer-technology cameras, advanced software, and stress-only protocols were associated with reduced ED, but worldwide adoption of these practices was generally low and varied significantly between regions. The implementation of dose-optimizing technologies and protocols offers an opportunity to reduce patient radiation exposure across all world regions.  相似文献   
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Aim

We sought to assess the magnitude of functional decline and the natural history of the operated kidney residual function after zero-ischemia nephron-sparing surgery (Z-NSS) in children with unilateral renal tumor (URT).

Patients and methods

50 children were treated for URT at our surgical unit between 1992 and 2016. Of these 12 who underwent Z-NSS were available for the current analysis. Operated kidney function was assessed by 99mTc-dimercapto-succinic acid (DMSA) renal scintigraphy. Operated kidney volume was assessed by renal ultrasonography.

Results

A positive correlation between split renal function and split renal volume was found (P?=?0.001). The subset of patients with ≥ 40% preservation of operated kidney function/volume (OKF/V) had no-time dependent changes during adolescence. The subset of patients with < 40% OKF/V preservation had a catch-up growth that after puberty reached values not much different from those with ≥ 40% OKF/V preservation. At 5?years of follow-up, 3 of 5 patients with baseline dysfunction (eGFR between 40.8 and 89.4?ml/min/1.73?m2) presented with a global renal function within normal range. After puberty, all patients presented with global renal function within normal values (eGFR between 95 and 151?ml/min/1.73 m2).

Conclusions

In children with URT who underwent Z-NSS, the pattern of OKF/V recovery suggests that compensatory catch-up growth capacity during childhood minimizes OKF/V decline more than Z-NSS.

Level of evidence

Level I prognosis study — prospective cohort study with > 80% follow-up and all patients enrolled at same time point in disease.  相似文献   
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Purpose

To evaluate the influence of percutaneous cryoablation for renal cell carcinoma on function of the affected kidney.

Materials and Methods

Between June 2016 and September 2017 at our institution, 12 inoperable patients underwent 15 cryoablation sessions for 17 small renal tumors. Of these, 9 patients who underwent 11 sessions of cryoablation were the focus of this study. For those patients, time-dependent changes in postoperative renal function were investigated by a retrospective review of clinical records. Evaluated were the estimated glomerular filtration rate (eGFR) and scintigraphy using 99m technetium-mercaptoacetyltriglycine (99mTc-MAG3) before and 1 week, 1–2 months, and more than 6 months after cryoablation.

Results

Mean baseline eGFR was 76.88 ± 29.82 mL/min/1.73 m2 (mean ± standard deviation; range, 23.4–112.5). Mean eGFR 1 week, 1–2 months, and more than 6 months after cryoablation were 74.56 ± 26.68 mL/min/1.73 m2 (21.0–101.1), 69.5 ± 25.28 mL/min/1.73 m2 (24.1–105.6), and 75.08 ± 26.25 mL/min/1.73 m2 (29.0–107.3), respectively. Changes were statistically insignificant (P = .6044, P = .6699, and P = .9038, respectively). Regarding split renal function, the mean baseline contribution of the affected kidney determined by 99mTc-MAG3 was 47.27% ± 6.14 (38.8%–57.0%). Mean contributions of the affected kidney 1 week after, 1–2 months after, and more than 6 months after cryoablation were 44.40% ± 5.37 (38.3%–53.6%), 44.57% ± 6.52 (34.35%–55.0%), and 45.41% ± 7.77 (34.4%–56.5%), respectively. Differences from baseline were significant for the earliest 2 periods (P = .0473 and P = .0334, respectively) but not the later period (P = .2532).

Conclusions

Results suggested that total renal function does not worsen after cryoablation; however, function of the affected kidney worsened after cryoablation but later partially recovered.  相似文献   
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Background/Objectives

Due to its rarity, epidermoid cyst in intrapancreatic accessory spleen (ECIPAS) is still a diagnostic dilemma during clinical practice. The aim of this review was to summarize the epidemiologic features and management of ECIPAS.

Methods

MEDLINE and EMBASE were searched for English articles reporting on ECIPAS up to April 30th, 2018 following the methodology suggested by the PRISMA guidelines. Categorical variables were reported as frequency and percentage. Continuous variables were reported as median (range).

Results

A total of 56 patients from 47 full articles were included for the final data synthesis. More than half of the ECIPASs (59%) were found incidentally. The female/male ratio was 1.33. ECIPAS is typically a single mono-/multi-lobular cystic lesions in the pancreatic tail with thickened cystic wall or various amount of solid component which had identical density/signal to the spleen on imaging examinations. The cyst is filled with serous or non-serous fluid. Recognition of the surrounding ectopic splenic tissue is the key point to diagnose ECIPAS. However, no preoperative examination was able to make a definite diagnosis. Almost all the patients (96%) received surgical treatment, due to the suspicion of pancreatic malignant or potentially malignant cystic tumor, especially mucinous cystic neoplasm (MCN).

Conclusions

Although seldom encountered, ECIPAS should be considered as a differential diagnosis for pancreatic cystic lesions, especially when solid component was detected. As a benign disease, unnecessary surgery should be avoided. Because it is difficult to make a definite diagnosis preoperatively by one single examination, multiple modalities may be required.  相似文献   
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目的建立东北苦菜Ixeris vesicolor DC.UPLC指纹图谱,并进行化学模式识别。方法东北苦菜甲醇提取物的分析采用CORTECS C18色谱柱(2.1 mm×150 mm,1.6μm);流动相0.1%磷酸水⁃乙腈,梯度洗脱;体积流量0.1 mL/min;检测波长(1~15 min,327 nm;15~50 min,360 nm);柱温35℃;进样量2μL。采用相似度分析和化学模式识别技术相结合的方法对其进行质量评价。结果10批样品指纹图谱中有19个共有峰,相似度均大于0.953。通过聚类分析将样品分成2类,主成分分析结果支持聚类分析结果,采用正交偏最小二乘法⁃判别分析筛选出了导致不同批次药材质量差异的3个共有峰,指认出2号峰(绿原酸)和12号峰(木犀草素)。结论该方法稳定可靠,可系统、全面地评价东北苦菜的药材质量。  相似文献   
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