Patient- and clinician-reported satisfaction with pharmacological stress agents for single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI)

Abstract

Objective:

The objective of this study was to compare clinician and patient measures of satisfaction with two pharmacological stress agents (PSA), regadenoson and dipyridamole, used in Single Photon Emission Computed Tomography (SPECT) Myocardial Perfusion Imaging (MPI).

Methods:

This observational study included patients who had undergone SPECT MPI with regadenoson or dipyridamole, as well as the clinician/clinical technologist who performed the test. Mean scores for individual item and domain scores of the main outcome measures were computed as well as the effect sizes (ES) of the mean difference in scores between treatment groups. Statistical significance of the mean item and domain score differences were assessed via Mann-Whitney tests.

Main outcomes measures:

Two self-report questionnaires which had beeb previously developed and validated: Patient Satisfaction/Preference Questionnaire (PSPQ) and Clinician Satisfaction/Preference Questionnaire (CSPQ).

Results:

A total of 87 patients (68 received regadenoson, 19 received dipyridamole) and nine clinicians/clinical technologists took part in the study. Patients had a mean age of 66.8?±?12.2 years, and 56.3% were male. Compared to dipyridamole, use of regadenoson was associated with greater clinician satisfaction on all items and domains of the CSPQ (p?<?0.001 for all comparisons). Among patients, regadenoson was associated with less bother and greater satisfaction than dipyridamole for all items on the PSPQ. These patients reported less stinging at the injection site (ES?=??0.66) and less nervousness during injection (ES?=??0.60). The PSPQ found that regadenoson patients were more satisfied with their PSA than dipyridamole patients in all areas.

Limitations:

This study utilized a relatively small sample size of dipyridamole patients and lacked an adenosine group. A broader sampling of professionals would also help demonstrate generalizability.

Conclusion:

Both patients and clinicians reported higher satisfaction with regadenoson compared to dipyridamole for SPECT-MPI. Clinicians were particularly satisfied with the preparation and administration aspects of the drug, while patients rated it highly on convenience and reduced incidence of side-effects.     

MSCT后处理技术显示冠状动脉狭窄形态与范围的比较研究

目的:比较研究多层螺旋CT后处理技术显示冠状动脉狭窄的形态与范围。方法:采用飞利浦多层螺旋CT工作站对随机抽取的120例病人冠状动脉采集图像进行重组,由2位影像医师比较多平面重组(multi-planar reformation,MPR)和CT仿真内窥镜(CT virtual endoscopy,CTVE)两种后处理技术对粥样硬化斑块形态的显示能力,同时比较MPR、曲面重建(curved planar reformat,CPR)和容积再现技术(volume rendering technique,VRT)在显示狭窄范围上的差异。结论:多层螺旋CT冠状动脉成像常用的后处理方法中,MPR血管轴位图最适合进行冠状动脉狭窄形态的研究;CPR最适合研究血管狭窄的范围。     

16排螺旋CT在膀胱移行细胞癌中的应用

目的:探讨16排螺旋CT对膀胱移行细胞癌的诊断价值。方法:回顾性分析36例经手术病理证实为膀胱移行细胞癌癌患者的CT及临床资料。结果:36例术前CT检出33例,3例未见异常。CT表现为局限性膀胱壁增厚7例,呈菜花状向腔内突出23例,乳头状突向腔内6例;增强扫描肿块均有不同程度强化。结论:16排螺旋CT对膀胱移行细胞癌的诊断有其独特的优越性,临床应用价值较高,可在临床推广应用。     

Differences in episode-based care costs for multidetector computed tomographic coronary angiography versus myocardial perfusion imaging for the diagnosis of coronary artery disease

Abstract

Background: Multidetector computed tomography (MDCT) is a novel method for diagnosis and prognosis of coronary artery disease (CAD). The opportunity costs that favour MDCT over other CAD diagnostic methods is currently unknown.

Methods: This study used an episodes of care cost model based on epidemiologic and economic data evaluating individuals without known CAD undergoing MDCT or myocardial perfusion scintigraphy (MPS). It was a multicenter retrospective database review of medical and pharmacy-related claims linked by episodes of care from 2002 to 2005. CAD-related episodes of care costs were examined 1-year downstream for patients after initial MDCT that were matched to patients who underwent MPS.

Results: After adjustment for patient factors, 1-year total CAD-related episodes of care costs for MDCT were 16.4% lower than MPS, by an average of $682 (95% confidence interval $14, $1,350) per patient. While costs per CAD-related episode were similar between MDCT and MPS groups ($4,284 vs. $4,277, p=0.08).

Conclusions: Patients without known CAD who undergo MDCT as an initial diagnostic test, compared to MPS, incurred fewer CAD-related episodes of care and lower overall CAD-related costs.     

基于LabVIEW的OCT信号采集和分析

虚拟仪器技术,使我们能够在计算机上按照自己的需求来设计实验与仪器,与相应的硬件设备结合使用,方便灵活而且开发周期短。它可以提高实验效率、降低实验成本。本文介绍了自行组建的双波长全光纤OCT系统以及实现该系统信号采集和分析的LabVIEW模块。     

基于不可分离MRA的快速小波去噪图像重建

提出了一种基于不可分离MRA的小波去噪重建算法.算法将投影数据进行二通道的小波分解,从而直接得到小波的近似系数和细节系数,对这些小波系数进行基于小波的阀值化去噪处理,再经过逆小波变换就得到了最终的重建图像.算法降低了复杂度,与可分离MRA重建算法比较速度更快,并且可以去噪.     

Health economic evaluation of Gd-EOB-DTPA MRI vs ECCM-MRI and multi-detector computed tomography in patients with suspected hepatocellular carcinoma in Thailand and South Korea

Objective: The effectiveness of treatment decisions and economic outcomes of using gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (Gd-EOB-DTPA-MRI) were compared with extracellular contrast media-enhanced MRI (ECCM-MRI) and multi-detector computed tomography (MDCT) as initial procedures in patients with suspected hepatocellular carcinoma (HCC) in South Korea and Thailand. Methods: A decision-tree model simulated the clinical pathway for patients with suspected HCC from the first imaging procedure to a confirmed treatment decision. Input data (probabilities and resource consumptions) were estimated and validated by clinical experts. Costs for diagnostic alternatives and related treatment options were derived from published sources, taking into account both payer’s and hospital’s perspectives. Results: All experts from Korea and Thailand agreed that Gd-EOB-DTPA-MRI yields the highest diagnostic certainty and minimizes the need for additional confirmatory diagnostic procedures in HCC. In Korea, from the payer’s perspective, total cost was USD $3087/patient to reach a confirmed treatment decision using Gd-EOB-DTPA-MRI (vs $3205/patient for MDCT and $3403/patient for ECCM-MRI). From the hospital’s perspective, Gd-EOB-DTPA-MRI incurred the lowest cost ($2289/patient vs $2320/patient and $2528/patient, respectively). In Thailand, Gd-EOB-DTPA-MRI was the least costly alternative for the payer ($702/patient vs $931/patient for MDCT and $873/patient for ECCM-MRI). From the hospital’s perspective, costs were $1106/patient, $1178/patient, and $1087/patient for Gd-EOB-DTPA-MRI, MDCT, and ECCM-MRI, respectively. Conclusions: Gd-EOB-DTPA-MRI as an initial imaging procedure in patients with suspected HCC provides better diagnostic certainty and relevant statutory health insurance cost savings in Thailand and Korea, compared with ECCM-MRI and MDCT.     

Cost minimization analysis of beta-blocker at the time of CT imaging for suspected of coronary heart disease in Japan

Objectives:

To conduct a cost-minimization analysis of landiolol for CT diagnosis of coronary heart diseases in patients with tachycardia in Japan.

Methods:

A decision-tree model was constructed to analyze costs from the healthcare payer’s perspective. Drug costs and diagnosis costs, computer tomography coronary angiography (CTCA), and coronary angiography (CAG), are adopted to the model. Landiolol is administered only to slow the heart rate to take CT images appropriately. Since some trials proved that there was no difference between landiolol and placebo in terms of efficacy and safety, this study conducted cost-minimization analysis. Of those suspected of coronary heart diseases, 22.5% are thought to be taking beta-blockers. The success rates for CT scanning for landiolol and placebo, derived from domestic trial data, were 81.4% (96/118, 77.8–84.9%) and 54.2% (64/118, 49.7–58.8%). Patients who failed to take a CT image were thought to take CAG. The healthcare cost was derived from a Japanese fee schedule. Costs of landiolol, CT imaging, and CAG are JPY2634 (USD1?=?JPY100, as of November 20, 2013), JPY38,116, and JPY101,322, respectively. The positive rate for CAG, derived from domestic trial data, was 37.1% (33/89, 32.0–42.2%). Various sensitivity analyses, both univariate and probabilistic ones, were conducted.

Results:

In the base case analysis, expected costs per patient for landiolol and placebo were JPY78,956 and JPY82,232, respectively. In budget impact analysis, 81,062 patients are eligible for landiolol and it can save JPY266million for whole patients. Sensitivity analyses suggested the robustness of the results.

Limitations:

This study did not consider any adverse effects in the decision-tree model. This model was developed especially for measuring the cost-saving effect of landiolol, through decreasing the number of patients who require CAG, due to imaging failure.

Conclusions:

Landiolol for CTCA diagnosis in patients suspected of coronary heart disease with tachycardia is thought to be cost saving.     

电容层析成像在双套管气力输送中的应用

以某公司双套管密相输送系统为试验平台,用电容层析成像技术对粉煤灰为输送物料进行了相关物理参数的测量研究。研制了适用于高压力下的8加4电极的电容层析成像传感器并进行了试验台的搭建安装。采用电容层析成像技术(ECT),对常温下气力输送的固体浓度、速度和质量流量进行了测试研究。研究结果证明电容层析成像技术在工业中的现实可行性。     

A minimum chi-squared method for indirect parameter estimation from Poisson data

In this paper, we introduce a new algorithm for estimating non-negative parameters from Poisson observations of a linear transformation of the parameters. The proposed objective function fits both a weighted least squares (WLS) and a minimum χ² estimation framework, and results in a convex optimization problem. Unlike conventional WLS methods, the weights do not need to be estimated from the datas, but are incorporated in the objective function. The iterative algorithm is derived from an alternating projection procedure in which "distance" is determined by the chi-squared test statistic, which is interpreted as a measure of the discrepancy between two distributions. This may be viewed as an alternative to the Kullback-Leibler divergence which corresponds to the maximum likelihood (ML) estimation. The algorithm is similar in form to, and shares many properties with, the expectation maximization algorithm for ML estimation. In particular, we show that every limit point of the algorithm is an estimator, and the sequence of projected (by the linear transformation into the data space) means converge. Despite the similarities, we show that the new estimators are quite distinct from ML estimators, and obtain conditions under which they are identical.