Numerical model for RF capacitive regional deep hyperthermia in pelvic tumors

A numerical model based on Finite Element Method (FEM) for the prediction of power density distribution and temperature during RF-capacitive hyperthermia treatment has been presented in the paper and the results are discussed. In particular the models are related to the treatment of pelvic tumors where it is more difficult to localize and focus heat in deep regions. The geometrical and physical model of the patient is reconstructed with a segmentation procedure by means of dedicated software. The geometrical meshed model has been used as input for the solution of coupled electromagnetic and thermal problems. A deep analysis of different configurations derived from specific scientific literature of the last years has been presented in the paper and discussed. The results obtained by FEM analyses have demonstrated the suitability of this method for the prediction of power and temperature distribution during RF capacitive hyperthermia and that the calculation procedure is an efficient mean to evaluate the efficacy of the heating system.     

癌热疗中超声无创监测技术的新进展

准确测量与控制组织的温度状态,是热疗应用和疗效评估面临的重要问题.本文跟踪国内外研究进展,对肿瘤热疗加热过程中利用组织超声特征参数无创监测的理论与实验研究进行综述.     

Localized heating characteristics of hyperthermia using a reentrant cavity

An applicator based on a reentrant cavity with excellent localized heating characteristics is proposed in order to treat deep tumours localized in the head and neck. Numerical and experimental analyses of the applicator, which produces an electromagnetic field distribution required for this type of localized heating, are performed. A simple and clear procedure for achieving localized heating requires applicator miniaturization. However, miniaturization causes an increase in the resonant frequency and leads to the degradation of the characteristics for heating deep tissue. Therefore, it is proposed that dielectrics be inserted into the applicator and the resonant frequency be reduced. From the results of the numerical analysis and experimental examination, it is shown that a deep region of 100–120 mm around the centre of a phantom can be heated.     

Localized heating characteristics of hyperthermia using a reentrant cavity

An applicator based on a reentrant cavity with excellent localized heating characteristics is proposed in order to treat deep tumours localized in the head and neck. Numerical and experimental analyses of the applicator, which produces an electromagnetic field distribution required for this type of localized heating, are performed. A simple and clear procedure for achieving localized heating requires applicator miniaturization. However, miniaturization causes an increase in the resonant frequency and leads to the degradation of the characteristics for heating deep tissue. Therefore, it is proposed that dielectrics be inserted into the applicator and the resonant frequency be reduced. From the results of the numerical analysis and experimental examination, it is shown that a deep region of 100-120 mm around the centre of a phantom can be heated.     

Optimization of selective hyperthermia

Selective hyperthermia can be a feasible treatment modality for deep tissue abnormalities. It is accomplished by using a laser or ultrasound noninvasively to transfer energy to a desired target causing tissue damage. This process has two potential benefits to medical professionals: simplicity of procedure and safety to patient. However, optimizing these selective interactions is difficult due to the number of variables. We propose an optimization coefficient relating the dynamic and geometric parameters of selective hyperthermia, and proceed to measure it in an experimental setup consisting of a near-infrared laser and laser-absorbing dye. To simulate tissue, gelatin phantoms are created using a combination of water, intralipid, and gelatin. Our experiments use a 1.00-cm-diam spherical phantom that is homogeneously enhanced with an indocyanine green (ICG) solution and placed inside a nontarget phantom and irradiated by an 805-nm diode laser. Temperature measurements taken at different locations are analyzed so optimization coefficients can be calculated for different parameters. This optimization coefficient compares the difference in temperatures from inside and outside the target. Analysis of the values after thermal equilibrium provides information about the best parameter selection. Our findings indicate that the optimal ICG concentration and power combination for our tested parameters are 0.083% and 0.97 W, respectively. Based on our analysis, optimization can be obtained by using this coefficient to compare the selectivity of several parameter combinations.     

Present status and tasks for future of point of care testing

This paper introduces Point-Of-Care Testing(POCT) developed by Bayer, mainly focusing on urine dipstick and tests for Diabetes Mellitus. Urinalysis using a dipstick has been widely carried out as a screening test for various kinds of diseases. Ten-pad urine dipstick is commercially available at the present time, and the desktop instruments have been developed for automatic optical reading, such as the Clinitek 50/100/500 systems. More recently, Bayer developed a new urine dipstick intended for reliable detection of the early stage of kidney disease without the influence of urine condensation or dilution. The dipstick adds 2 pads to conventional urine dipsticks: one for the measurement of small amounts of protein(albumin), and the other for creatinine. A semi-quantitative urine protein-to-creatinine ratio is based on these results. There have been significant advances made in blood glucose meters for POCT in terms of reliability, simplicity of operation, sample volume, etc. And not only healthcare professionals but also patients with diabetes have used POCT meters. Dexter-ZII is available as one of these meters. DCA2000 is a portable analyzer for measuring HbA1c in 6 min. Patients could be treated and instructed on the basis of HbA1c measured by DCA2000. As one of the tasks for the future, it is preferable that some POCT systems be available as OTC for ordinary people to manage their own health. Also, I emphasize that it is important to review the usability of conventional urine dipsticks like a check for drug side effects, as well as for developing new urine analyses.     

癌热疗中超声无创测温方法的研究

癌热疗中组织温度的测控直接影响到热疗的效果 ,利用超声可以实现热疗中组织温度的无创检测。本文介绍了癌热疗中目前所采用的几种超声测温方法 ,对各种方法的原理及存在的问题进行了分析 ,概述了超声无创测温当前国内外的研究现状     

磁流体肿瘤热疗中超声无损测温技术的研究进展

磁流体肿瘤热疗技术(magnetic fluid hyperthermia,MFH)作为一种安全、高效的新型肿瘤治疗方法,近年来得到快速发展。MFH中最为关键的技术之一是肿瘤的温度检测。超声无损测温法由于能够实现准确实时的温度变化检测,近年在MFH技术中受到广泛关注,现已成为MFH技术中最为重要的测温方法之一。本文综述了近年国内外在MFH超声无损测温领域中的研究现状和发展状况。首先介绍了几种常见温度无损测温技术的发展现状,然后着重介绍了超声无损测温的研究状况,最后对超声无损测温的未来发展趋势进行了展望。     

皮肤病的非恒温加热仿真分析

目的 为了达到皮肤病热疗法的最大疗效和最小副作用,在之前的基础上,进行探索性的非恒温加热仿真实验.方法 利用数学工具(Matlab)对治疗时皮肤的非恒温加热波形进行仿真分析和选择.结果 与先前的恒温加热疗法相比,非恒温加热时皮肤里层的温度呈上升趋势,而恒温加热则是下降的.结论 相对恒温加热,非恒温加热对里层的细菌更具有抑制作用,且有更小的副作用.     

Digital chest radiography at the University of Chicago: Present status and future plans

Storage-phosphor computed radiography and film digitization systems have been in routine clinical use at the University of Chicago for several years. During this time we have implemented numerous modifications including techniques for scatter reduction, image processing enhancements and display systems to improve the image quality and utility of these devices. We have also evaluated the image quality and functionality of digital systems relative to conventional screen-film radiography. In this paper, we review our experience and summarize our impressions. In addition, we summarize our plans for a rapid transition into picture archiving and communication systems, with hardcopy interpretation being phased out for most modalities over the next 2 to 5 years.     

Present and future of cephalosporins

The cephalosporins today, and particularly the third-generation cephalosporins, still possess an activity spectrum and microbiological potency such that several authors continue to regard them as the gold standard of beta-lactam antibiotic therapy. Comparison with the rapid onset of resistance to other extensively used drugs, such as the macrolides and quinolones, places the emphasis once again squarely on the great reliability of the antibacterial action of the cephalosporins and, particularly, on the validity of their targets at the bacterial cell level. The beneficial use of cephalosporins for a vast range of infectious diseases is amply confirmed by the most authoritative international guidelines and bears witness to the role of great importance that these drugs still play in all fields of antibiotic therapy, as a result of the variety of the compounds available, their broad spectrum of antibacterial activity, their multiple clinical potentialities and their excellent tolerability. The cephalosporins therefore continue to constitute a firm reference point in the overcrowded antibiotics scene and, if used appropriately, promise to conserve their leading role for a long time to come.