PACS影像工作站图像浏览功能的设计

介绍了从控制系统角度出发设计基于DICOM3．0标准的PACS图像浏览功能模块的方法，并着重说明了DICOM~器和图像文字信息映射转换器两个主要控制单元。     

基于DICOM3.0标准构建放射治疗数字系统

目的通过DICOM3.0标准接口,构建放射治疗数字系统。方法以星型拓扑结构联接该系统的各模块,在放疗TPS工作站上实现放疗数字系统服务器功能。遵守TCP/IP网络协议,采用B/S模式的Web浏览器方式,在Windows窗口下实现数据的共享。结果构建放射治疗数字系统,使TPS各工作站实现了资源共享。结论 DICOM 3.0标准,适应医院信息系统发展的要求,有利于提高放射治疗的效率,提升放射治疗质量控制和质量保证。     

Use of Liraglutide 3.0 mg for Weight Management in a Real-World Setting in Switzerland

IntroductionData from randomized controlled trials show that liraglutide 3.0 mg, in combination with diet and exercise, is associated with greater weight loss than diet and exercise alone in patients with obesity. In practice, the utilization of weight loss drugs is influenced by various factors, including the cost of treatment. We conducted a retrospective, observational study to assess the effectiveness of liraglutide 3.0 mg and patients'' persistence on treatment, in a real-world setting.MethodsData were extracted from de-identified electronic medical records from an obesity management clinic in Switzerland. Changes in body weight and blood pressure were evaluated in the full cohort (N = 277, 19% of whom had undergone bariatric surgery) and subgroups who were persistent on liraglutide 3.0 mg for at least 4 months (n = 236), 7 months (n = 159), or 12 months (n = 71).ResultsMedian persistence on liraglutide was 6.8 months. Median maximum dose received was 1.5 mg, and 13.7% of patients reached the maintenance dose of 3.0 mg. Mean 7-month weight change from baseline in the full cohort was −4.1 kg (95% confidence interval: −5.0, −3.2; p < 0.001; −4.2%). Weight change was −4.4 kg (−4.7%) in the ≥4-month persistence subgroup at 4 months, −5.1 kg (−5.3%) in the ≥7-month persistence subgroup at 7 months, and −7.5 kg (−7.1%) in the ≥12-month persistence subgroup at 12 months (all p < 0.001). In the full cohort, 40% and 14% of patients lost ≥5% and >10% of body weight at 7 months, respectively. Weight loss did not differ significantly according to history of bariatric surgery (p = 0.94). Diastolic blood pressure decreased (from 87.0 to 83.9 mm Hg at 7 months; p = 0.018), with no significant changes in systolic blood pressure. Approximately two-thirds of patients did not have health insurance that could cover the cost of liraglutide.ConclusionIn a real-world setting with low insurance coverage and with most patients not reaching the recommended maintenance dose of 3.0 mg, the use of liraglutide, in combination with diet and exercise, was associated with clinically meaningful weight loss.     

Evaluation of intrarenal oxygenation by BOLD MRI at 3.0 T

PURPOSE: To examine the benefit of using higher field strengths for BOLD MRI to detect changes in renal medullary oxygenation following pharmacological maneuvers. MATERIALS AND METHODS: Renal BOLD MRI, primarily at 1.5 T, has been shown to be useful for monitoring changes in medullary oxygenation status. We performed the present studies on a 3.0 T scanner using a multiple gradient-echo (mGRE) sequence with a multicoil array to acquire 16 T2*-weighted images within a single breath-hold. Data were obtained before and after administration of furosemide (20 mg iv). RESULTS: The baseline renal R2* (mean +/- SE) at 3.0 T was 37.4+/-1.2 Hz in the medulla, and 21.8 +/- 1.2 Hz in the cortex. The BOLD response to furosemide (DeltaR2*) at 3.0 T was 11.8 +/- 1.1 Hz in the medulla, and 3.0 +/- 0.5 Hz in the cortex. CONCLUSION: Higher magnetic field strength is beneficial for renal BOLD MRI studies. The cortico-medullary contrast on the R2* map was significantly improved at 3.0 T, with no evidence of increased bulk susceptibility artifacts. Baseline R2* and DeltaR2* in the renal medulla at 3.0 T were both significantly higher compared to our previously reported data obtained at 1.5 T.     

Web3．0对虚拟参考咨询的影响

网络通讯技术的发展日新月异，继Web1．0、Web2．0后，Web3．0这一互联网发展的新趋势将对图书馆的虚拟参考咨询在工具技术、服务模式、人员素质等方面发生作用，促使其最大限度地满足用户全方位、多样化和个性化的需求。     

基于对等网络的DICOM传输模式研究

通过分析了标准DICOM影像传输的过程及特点,设计出一种基于对等网络的DICOM传输模式。文中详细介绍了基于对等网络的DICOM传输的工作流程和建立临时数据服务源分解传输任务的方法。最后通过实验验证了DICOM影像传输适应对等网络的要求。     

131I标记抗人肝癌单克隆抗体人体内照射剂量计算

目的观察131I-抗肝癌细胞单克隆抗体(131I-Hepama-1)的生物学分布情况,估算全身正常器官及肿瘤组织内的照射剂量,评价131I-Hepama-1治疗原发性肝癌的安全性及可行性。方法5例原发性肝癌患者,分别于静脉注射131I-Hepama-1后10min～7d采集全身前、后位图像,获得131I-Hepama-1全身生物学分布情况;利用ROI技术勾画各时相、各器官和肿瘤组织的放射性计数,同时留取患者24h尿样。使用ORIGEN5.0统计软件得到各器官和肿瘤的时间-放射性曲线,分别计算各源器官的累积活度和放射性滞留时间,再由计算内照射剂量软件MIRDOSE3.0得出包括脑、甲状腺、肺、肾、肠道等正常器官及肿瘤组织的内照射吸收剂量。结果5例患者各主要器官和肿瘤的平均内照射吸收剂量分别为:全身0.17Gy,正常肝组织2.06Gy,红骨髓0.07Gy,肺1.91Gy,甲状腺49.55Gy,肿瘤16.18Gy。结论经静脉注射131I-Hepama-1治疗原发性肝癌,肿瘤组织可获得较大的内照射吸收剂量,肝脏和其他脏器的吸收剂量较小,临床使用安全,对于治疗肝细胞肝癌具有一定的价值。     

Cardiac MRI of ischemic heart disease at 3 T: potential and challenges

Cardiac MRI has become a routinely used imaging modality in the diagnosis of cardiovascular disease and is considered the clinically accepted gold standard modality for the assessment of cardiac function and myocardial viability. In recent years, commercially available clinical scanners with a higher magnetic field strength (3.0 T) and dedicated multi-element coils have become available. The superior signal-to-noise ratio (SNR) of these systems has lead to their rapid acceptance in cranial and musculoskeletal MRI while the adoption of 3.0 T for cardiovascular imaging has been somewhat slower. This review article describes the benefits and pitfalls of magnetic resonance imaging of ischemic heart disease at higher field strengths. The fundamental changes in parameters such as SNR, transversal and longitudinal relaxation times, susceptibility artifacts, RF (B1) inhomogeneity, and specific absorption rate are discussed. We also review approaches to avoid compromised image quality such as banding artifacts and inconsistent or suboptimal flip angles. Imaging sequences for the assessment of cardiac function with CINE balanced SSFP imaging and MR tagging, myocardial perfusion, and delayed enhancement and their adjustments for higher field imaging are explained in detail along with several clinical examples. We also explore the use of parallel imaging at 3.0 T to improve cardiac imaging by trading the SNR gain for higher field strengths for acquisition speed with increased coverage or improved spatial and temporal resolution. This approach is particularly useful for dynamic applications that are usually limited to the duration of a single breath-hold.     

Cardiac cine MRI: comparison of 1.5 T, non-enhanced 3.0 T and blood pool enhanced 3.0 T imaging

INTRODUCTION: Cardiac cine imaging using balanced steady state free precession sequences (bSSFP) suffers from artefacts at 3.0 T. We compared bSSFP cardiac cine imaging at 1.5 T with gradient echo imaging at 3.0 T with and without a blood pool contrast agent. MATERIALS AND METHODS: Eleven patients referred for cardiac cine imaging underwent imaging at 1.5 T and 3.0 T. At 3.0 T images were acquired before and after administration of 0.03 mmol/kg gadofosveset. Blood pool signal-to-noise ratio (SNR), temporal variations in SNR, ejection fraction and myocardial mass were compared. Subjective image quality was scored on a four-point scale. RESULTS: Blood pool SNR increased with more than 75% at 3.0 T compared to 1.5 T (p<0.001); after contrast administration at 3.0 T SNR increased with 139% (p<0.001). However, variations in blood pool SNR at 3.0 T were nearly three times as high versus those at 1.5 T in the absence of contrast medium (p<0.001); after contrast administration this was reduced to approximately a factor 1.4 (p=0.21). Saturation artefacts led to significant overestimation of ejection fraction in the absence of contrast administration (1.5 T: 44.7+/-3.1 vs. 3.0 T: 50.7+/-4.2 [p=0.04] vs. 3.0 T post contrast: 43.4+/-2.9 [p=0.55]). Subjective image quality was highest for 1.5 T (2.8+/-0.3), and lowest for non-enhanced 3.0 T (1.7+/-0.6; p=0.006). CONCLUSIONS: GRE cardiac cine imaging at 3.0 T after injection of the blood pool agent gadofosveset leads to improved objective and subjective cardiac cine image quality at 3.0 T and to the same conclusions regarding cardiac ejection fraction compared to bSSFP imaging at 1.5 T.     

Bilateral ce-MR angiography of the hands at 3.0 T and 1.5 T: intraindividual comparison of quantitative and qualitative image parameters in healthy volunteers

The purpose of this study was to determine the benefit of bilateral contrast-enhanced MR angiography (ce-MRA) of the hands at 3.0 Tesla (T) compared with an established 1.5-T technique in healthy volunteers. Intraindividual bilateral ce-MRA of the hands was performed at 1.5 T and 3.0 T in 14 healthy volunteers using a timed ultra-fast GRE sequence featuring parallel acquisition. The evaluation comprised measurement of the vessel signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), rating of the image quality and the assessment of artefacts and venous contamination. At 3.0 T, SNR improved up to 95% and CNR up to 129%. The image quality of the larger inflow arteries, the palm arches and common digital arteries was good or sufficient at either magnetic field strengths. However, 3.0-T MRA was clearly superior in the depiction of the digital arteries. Ce-MRA of the hand clearly profits from the use of 3.0 T. Compared with 1.5 T, a substantial increase of CNR is found resulting in a significantly better delineation of the small digital arteries. Saturation affects more the SNR of the perivascular tissue than the contrast-enhanced blood, and thus leads to a marked increase of CNR at 3.0.