Roentgenologic control of central venous catheters

765 central venous catheters were controlled during 1976 to 1980 at the Department of Radiology of the St. Josef-Hospital at Heidelberg. These control checks revealed that the position of the catheters required correction in 42.3 per cent of the cases. The rate of complications was 1.05 per cent. Attention is drawn to the importance of correct positioning of the catheter to avoid complications, and also to the need for radiological control of the catheter position.     

Quality control of technetium-99m DTPA: correlation of analytic tests with in vivo protein binding in man

When [99mTc]DTPA is administered, a small fraction of the activity (presumably an impurity) is bound to plasma proteins. This causes an error in the calculation of glomerular filtration rate from plasma clearance. This paper presents two methods of laboratory quality control for measuring the fraction that binds to plasma proteins. One method involves in vitro binding to human serum albumin followed by gel filtration. The other method involves descending paper chromatography on wet pre-equilibrated anion exchange paper. In a series of 80 patients, correlation was demonstrated between laboratory characteristics and actual clinical performance of the [99mTc]DTPA preparation. Both laboratory methods appear suitable for routine quality control.     

安全性药理学试验的质量保证

安全性药理学（safety pharmacology）试验是最晚列入良好实验室规范（good laboratory practice,GLP）管理的毒理学试验。安全性药理学试验为多个小型试验的组合,涉及到多组生理功能的检测,在药品非临床研究质量管理规范和质量保证方面有其特殊性。该文从安全性药理学的定义和范围、研究内容、执行GLP的要求、实验室资质的确认、试验关键阶段的检查、原始资料和报告的审核等方面分析了安全性药理学试验质量保证的程序、要求和注意事项。     

Blood clot formation in angiographic catheters. In vitro tests with various contrast media

Human blood was injected into angiographic catheters filled with contrast media or flushing media. The catheters were allowed to stand at 37 degrees C for 10, 20 or 30 min. Physiologic saline was then injected through the catheters, the catheter contents were shaken and filtered, and any clots were identified. Diatrizoate, ioxaglate, iohexol, iopamidol and iopromide were tested. Physiologic and heparinized saline were used as controls. At 10 min, clots were found in 65 per cent of the catheters filled with physiologic saline, in 25 per cent with non-ionic media, in 19 per cent with heparinized saline, and in 4 per cent with ionic contrast media. At 30 min, all catheters with physiologic saline, 85 per cent with non-ionic contrast media, 46 per cent with heparinized saline and 23 per cent with ionic contrast media contained a clot. Although all the contrast media were anticoagulants, a more careful angiographic technique is needed for non-ionic media. All the non-ionic agents showed equal results. Physiologic saline without heparin is not suitable for flushing during angiography.     

Transhepatic venous catheters for hemodialysis

Purpose

To describe our experience with the technique of transhepatic venous access for hemodialysis and to evaluate its functionality and complications.

Patients and methods

From March 2012 till October 2012, 23 patients with age ranging from 12 to 71 years old having end-stage renal disease (ESRD) were included in our study and were subjected to transhepatic venous catheter insertion. In 21 patients there were not any remaining patent peripheral venous accesses. In 2 patients there were only a last one venous access needed to be preserved. Thus, it was decided to make THVA. In all the 23 patients the indication was palliative due to inoperability which was because of inability to insert an arterio-venous graft or making another arterio-venous fistula. Complications were evaluated and calculated in terms of number of procedures, infection, dislodgement and outcome; in terms of disfunctionality of the catheter.Follow-up was performed by monitoring the catheter dialysis rate in each session, abdominal ultrasonography, fluoroscopy or CT. Mean survival time and median survival time from the start of treatment were calculated using Kaplan–Meier method.

Results

Twenty-three patients required a single transhepatic access procedure. Because of catheter dislodgment, two patients required a second access placement procedure, which resulted in a total of 25 separate transhepatic access sites in 23 patients. Technical success was achieved in 22 procedures. Functionality success was achieved in 20 patients. Functionality failure occurred in 3 patients.The trans-hepatic catheters stayed in place between 90 and 300 days. Complications occurred in 14 patients.

Conclusion

Based on our findings, transhepatic hemodialysis catheters have proven to achieve good long-term functionality. A high level of maintenance is required to preserve patency, although this approach provides remarkably durable access for patients who have otherwise exhausted access options.     

Diminished radiopacity of contrast material: a urographic sign of ureteral calculus.

Eleven patients with unilateral ureteral calculus had excretory urography which showed the radiopacity of excreted contrast material to be diminished on the side of the calculus. This finding was of diagnostic importance in nine patients who demonstrated little or no dilatation of the urinary tract proximal to the calculus. Other forms of unilateral renal disease, such as acute pyelonephritis, can produce the same urographic finding.     

Technical report: an injection technique for repositioning subclavian catheters

Malpositioned central venous catheters need to be repositioned so as to avoid local toxicity from chemotherapeutic and other agents and to prevent venous thrombosis. We describe a simple, safe and effective technique for repositioning silicone central venous catheters, by using a hand injection of sterile saline. It was successful in all nine patients in whom it was attempted, with no complications. Five catheters were single lumen and four were double lumen. We feel that this method should be attempted prior to the use of more invasive techniques.     

Low-dose streptokinase for occluded Hickman catheters

In 14 patients, 16 episodes of occluded Hickman catheters were evaluated by contrast venography. In 13 instances, a fibrin sheath occluding the distal catheter was observed. A mechanical problem was responsible for occlusion in three catheters. Low-dose streptokinase effectively restored lumen patency in 12 catheters (92%) occluded by a fibrin sheath.     

Quality control of 99mTc-labeled dextran for lymphoscintigraphy

99mTc-labeled dextran has been suggested as a lymphoscintigraphic agent. However, quality-control results from previous studies have been controversial. In this study, the optimal concentration of stannous ion and pH value were determined to obtain maximal labeling. Paper and thin-layer chromatography showed total labeling efficiency as high as 98.4%. Anthrone test of the supernatant of the segments from thin-layer chromatographic strip was performed. Colorimetric determinations verified that dextran was found in the same locations as the peak radioactivity.     

Quality control in imaging standards for stroke diagnosis

Hospitals in "Rhineland-Palatinate" and "Saarland" as well as in other German states are using benchmarking in quality control and to improve diagnostic procedures and treatment in stroke. The goal is a continuous learning process in which participants improve their performance by comparing themselves to the highest quality care. CCT/MRI procedures are an important tool in stroke therapy and prophylaxis. Structural quality was good in all 39 participating hospitals. The best evidence-based indicator in quality control of CCT/MRI procedures is the process quality in performing these procedures within 3 h after stroke onset. Process quality was better in hospitals that cared for many stroke patients than in those with fewer cases. The latter hospitals also had less clinical and diagnostic competence. Benchmarking in quality control was successful because over the years improvement in stroke management was obvious in the participating hospitals.     

数字乳腺摄影系统的质量控制检测与评价

目的 对3套数字乳腺摄影系统进行质量控制检测与评价。方法 应用欧洲乳腺癌普查和诊断质量控制导则中推荐的方法,结合国内乳腺摄影评价标准,对3套数字乳腺摄影系统进行X线发生器性能质量控制检测与评价;分别应用直接数字化X线摄影技术(DR)、相位对比乳腺摄影(PCM)和计算机X线摄影技术(CR)系统在4个厚度下(30、40、50及60mm)对乳腺专用对比度细节检测模体(CDMAM3.4)进行AEC曝光成像,计算与评价每一厚度下的平均腺体剂量(AGD)和影像质量因子(IQF)。结果 DR和CR的X线机性能检测符合现有标准;等效PMMA厚度分别为30、40、50、60mm时,DR系统的AGD分别为1.20、1.42、1.75、2.20mGy;PCM系统AGD分别是0.82、1.19、1.33、1.70mGy;CR系统AGD为0.59、0.88、1.47、2.19mGy。在相应的模体厚度下,DR系统的IQF值为21.36、21.57、27.25和30.58;PCM和CR系统的IQF值分别为28.02、29.10、35.90、41.24和39.78、39.30、43.85、48.08。结论 GBZ186-2007标准不适用于PCM系统X线机性能部分性能的评价。本研究的3套系统自动曝光下平均腺体剂量均符合欧洲标准。在国内检测规范欠缺的情况下,可参考国际标准或指南对数字乳腺系统进行常规监测。     

Quality control of 99mTc-labeled dextran for lymphoscintigraphy

^99mTc-labeled dextran has been suggested as a lymphoscintigraphic agent. However, quality-control results from previous studies have been controversial. In this study, the optimal concentration of stannous ion and pH value were determined to obtain maximal labeling. Paper and thin-layer chromatography showed total labeling efficiency as high as 98.4%. Anthrone test of the supernatant of the segments from thin-layer chromatographic strip was performed. Colorimetric determinations verified that dextran was found in the same locations as the peak radioactivty.     

Assessment of radiologic tests: control of bias and other design considerations

The assessment of new radiologic tests can be seriously hampered by the presence of systematic bias. Biases can arise from incomplete verification of the sample population; omission of uninterpretable tests; absence of a definitive reference test; extraneous factors affecting interpretation; and extrapolation factors including variations in test efficacy among patients, hospitals, and the radiologists who interpret the tests. The authors review these biases that affect the results of efficacy studies and provide guidelines to avoid these problems.