射频毁损灶体积与近红外光学参数的相关性研究

射频热凝毁损术治疗帕金森病有效率达90%以上,但手术过程中毁损体积的量化问题研究得不多,通过控制毁损温度和时间来确定毁损灶的范围是有效的,但其量化关系还未见报道.本研究建立了体外蛋清射频毁损灶和活体内大鼠脑射频毁损灶模型,探讨毁损体积随毁损温度及时间两个参数变化的规律,利用1stOpt数学拟合工具拟合了相关度较高的数学模型,通过这一关系就能够根据预毁损体积选择相应的温度和时间,提高毁损术效果;使用特制的内置四光纤探头测量了大鼠脑靶点处的生物组织光学参数优化散射系数μs'.实验数据表明,μs'的变化规律与相应毁损温度时间下的毁损体积变化规律相似,证明了其与射频毁损灶体积有很好的相关性.建立了毁损体积与优化散射系数之间的关系模型,为探索近红外光谱技术在射频毁损手术实时监控中的应用提供了实验依据.病理学检测证明了实验的有效性.研究结果为探索近红外光谱技术在帕金森病射频毁损手术实时监控中的可行性提供了实验依据.     

超声影像在射频治疗肝癌中的作用

原发性肝癌和转移性肝癌是最常见的恶性肿瘤之一,占我国恶性肿瘤的第二位,目前外科手术仍认为是唯一可能被治愈的方法,是由于肝癌发病隐匿,大多数患者就诊时已失去手术机会,近年来一些微创性的介入性治疗方法能有效治疗肝肝肿瘤,如：无水酒精注射,微波治疗。激光及射频毁损疗法,等,其中射频毁损治疗作为肝癌局部热疗的新方法,以其方法简单,安全,热场可控,可做到一次性原位整体细胞灭活而越来越受到关注,超声是引导射频治疗最常用的技术,而且在评价疗效方面起着重要的作用。     

FGZ—3半导体激光治疗机设计与研制

本文介绍一种具有多波长激光输出的半导体激光治疗机的设计与研制，采用新型的瓦级单量子阱半导体激光翼、ＨｅＮｅ激光器与Ｙ型光纤耦合器，整机可从单光纤或四路光纤输出８１０ｎｍ、６３２．８ｎｍ两种激光。本机在激光生物医学应用中获良好效果。     

一种带抽烟吸引及照明通道的激光光纤导引器的设计

本装置为一种具有抽烟吸引及照明通道功能的激光光纤导引器,解决了体腔激光手术时：（1）激光光纤不易把持固定;（2）术野照明;（3）组织汽化切割产生的烟雾及腔内分泌物不易排出等问题。     

激光腔内照射治疗仪的设计

本研究设计了一种低强度激光腔内照射治疗装置。此装置结合了传像光纤和传光光纤，具有可视性，可将激光准确导入病灶。为利用激光治疗腔内疾病提供了一种方便、低廉，易于重复的手段。     

单侧颞叶癫癎伽玛刀和定向射频热凝术的效果比较

目的探讨深部电极脑电图证实为单侧颞叶内侧的癫癎患者进行伽玛刀和立体定向射频热凝毁损术疗效的区别。方法：2008年3月～2011年8月,深部电极脑电图确认为单侧颞叶内侧癫癎的患者,据深部电极脑电图所显示的异常范围引导,随机进行伽玛刀治疗和立体定向射频热凝毁损术。伽玛刀治疗颞叶内侧结构时,周边剂量8～13 Gy,平均9．3 Gy,中心剂量16～26 Gy,平均18．5 Gy,50％等剂量曲线;立体定向射频热凝毁损术时,毁损温度70～90℃,平均76．3℃,毁损时间90～120s,平均108．5s,毁损间隔3 mm。结果：术后24～65个月,随访可及的21例伽玛刀治疗,其中癫癎完全缓解（Engel Ⅰ级）2例,癫癎发作很少和几乎消失（EngelⅡ级）3例,显著的改善（Engel Ⅲ级）8例,不显著的改善（Engel Ⅳa级）7例,无改变（Ⅳb级）1例;立体定向射频热凝毁损术10例,其中癫癎完全缓解（Engel Ⅰ级）5例,癫癎发作很少或几乎消失（EngelⅡ级）2例,显著的改善（Engel Ⅲ级）0例,不显著的改善（Engel Ⅳa级）2例,癫癎发作更重（ⅣC级）1例。应用SPSS 17．0分析,两组完全缓解（Engel Ⅰ级）率比较差异有统计学意义（P=0．022）,两组完全缓解和癫癎发作很少和几乎消失（Engel Ⅰ级＋Ⅱ级）率比较差异有统计学意义（P=0．021）。结论：对深部电极脑电图证实为单侧颞叶内侧癫癎的患者,SRT的完全缓解率和癫癎基本控制率都高于伽玛刀治疗者。     

射频热毁损治疗肝脏恶性肿瘤

射频热毁损 (radiofrequency therm al ablation,RFA)是国内外近几年来开展的一项治疗肝脏恶性肿瘤的新技术 ,具有快速毁损肝脏肿瘤而且安全性高、并发症少、患者易接受、可重复治疗等诸多优点 ,具有良好的应用前景 〔1～ 4〕。1　射频治疗仪和射频热毁损原理射频 (RF)是一种频率在 30 HHz- 30 0 MHz的高频电磁波 ,电流高度集中 ,随高频发生离子振荡而产生 90～ 12 0℃的高温。射频治疗仪主要由射频发射器、针式治疗电极、弥散电极板及 B超监视系统等部分组成〔1 ,2〕。目前使用的主流机型为 RF2 0 0 0 TM型治疗仪 ,其发射器频率为 46…     

自动恒温KTP激光治疗仪

激光治疗与诊断各种疾病已是现实。三十多年来,激光应用技术已经逐步深入到医学发展的各领域中,而且已经解决了医学中的许多难题,这说明激光治疗仪已成为医学中不可缺少的重要医疗器械。下面,我们将最新研制的自动恒温KTP激光治疗仪控制系统予以报道。1　自动恒温控制结构图首先给出KTP激光治疗仪自动恒温控制结构图,图中,各电器单元经过优化组合后,分别承担不同功能,恒温传感导线及光纤贯穿在医用硅胶管中;光纤末端与检温传感探头密封安装在微型透明容器内,组合成一种特殊的光纤探头。这一装置类似胃镜探测仪,可伸展到食道、胃及人体内…     

神经网络和用于荧光导引的激光可塑管的传统分类器

在激光可塑管中,观察组织的荧光谱可用于组织分类,以识别是粥样硬化还是正常,并可指导粥样斑的选择式激光切除。我们研究了一种方法,用受低功率激光辐射的组织的荧光谱作为区别正常组织和斑的方法。通过一个光纤管传导低功率辐射到目标部位不伤害组织。这个光纤管可收集荧光辐射和反它传给光谱计。光谱通过     

激光热疗中生物组织的光热特性响应以及动态热损伤研究

考虑到生物组织的光学、热学特性参数以及血液灌注率与组织温度和组织热损伤的依赖关系 ,模拟了激光热疗中激光在生物组织中的传输、生物组织的动态热响应和热损伤 ,以及血液灌注率的变化。通过分析激光功率和激光头尺寸对热疗效应的影响 ,得出了一些有益于肿瘤热疗临床的结论。     

Single-fibre laser Doppler flowmetry

A laser Doppler flowmeter with one optical fibre guiding light to and from the tissue under study has been developed. The outer diameter of the probe equals the optical fibre diameter (0·5 mm). The small size makes it useful for studying the deep tissue perfusion in organs. Differential-channel operation was compared with the single-channel operation and the benefit of this technique was evaluated theoretically as well as in a fluid model resembling tissue perfusion. The signal-to-noise improvement ratio was calculated and found to be related to the number of coherence areas detected and to the broadband noise of the laser. In vivo experiments in the gastrocnemius muscle of the pig were performed to compare the results from the single-fibre technique with those of the electromagnetic flowmeter. Linear regression analysis of femoral blood flow data obtained with the electromagnetic flowmeter and local muscle blood flow measured with the single-fibre technique showed a correlation coefficient of 0·88 (n=36, p<0·001).     

LOBULAR CAPILLARY HEMANGIOMA OF THE ESOPHAGUS A Case Report and Review of the Literature

A case of lobular capillary hemangioma In the lower portion of the eosphagus in a 49-year-old woman was investigated. Lobular capillary hemangioma of the esophagus must be a rare lesion. We have been unable to find s single case in the literature. The excised lesion consisted macroscopically of a single strip of red tissue ulcerated and covered with a white exudate, 7 mm in length, with an attached vascular pedunculated lesion no more than 4 mm in diameter. Microscopically, the pedunculated lesion had the features of a capillary hemangioma with a circumscribed aggregate of capillaries arranged In one or more lobules. Similar cases from the oral and nasal mucous membranes were recorded In 1980 by M ills et al .¹³.     

Focal nodular hyperplasia of the liver: A clinicopathologic study and review of the literature

We reviewed the clinical records and pathologic material of 20 patients with biopsy proven hepatic focal nodular hyperplasia. The majority of the patients were females of child bearing age, five of whom had a history of oral use of contraceptives. In every instance focal nodular hyperplasia was an incidental finding; liver function tests were always normal. Focal nodular hyperplasia is a distinct histopathologic entity, distinguishable from liver cell adenoma. Specifically it consists of nodular aggregates of cytologically normal hepatocytes with foci of intranodular bile duct proliferation. Focal nodular hyperplasia appears to be a benign entity, even in patients in whom the lesion was not excised. The association between focal nodular hyperplasia and oral use of contraceptives may be coincidental, although hormonally related vascular changes may be responsible for rupture of the lesion.     

Effect of embedded optical fibres on the mechanical properties of cochlear electrode arrays

Incorporating optical fibres in cochlear electrode arrays has been proposed to provide sensors to help minimise insertion trauma and also for the delivery of light in optical nerve stimulation applications. However, embedding an optical fibre into an electrode array may change its stiffness properties, which can affect the level of trauma during insertion. This report uses measurements of buckling and deflection force to compare the stiffness properties of a range of cochlear electrode arrays (Nucleus straight array, rat array, cat array and guinea pig array) with custom arrays containing an embedded optical fibre. The cladding diameters of the optical fibres tested were 125 µm, 80 µm and 50 µm. The results show that the stiffness of the optical-fibre-embedded arrays is related to the diameter of the optical fibre. Comparison with wired arrays suggests optical fibres with a diameter of 50 µm could be embedded into an electrode array without significantly changing the stiffness properties of the array.     

High intensity focused ultrasound--a surgical technique for the treatment of discrete liver tumours

The treatment of discrete liver tumours is often a difficult clinical problem. High intensity, focused ultrasound may provide one form of therapy for such disease. The ability to focus ultrasound precisely on a predetermined volume allows the possibility of selective tissue destruction at this position without damage to intervening tissues. We have investigated this both in vivo and in excised liver samples in vitro. Quantitative and qualitative studies have been carried out on the relationship between the ultrasonic exposure and the lesion shape, position and volume. In addition, the highly echogenic nature of the ultrasonic lesion has been studied, in an attempt to determine whether 'real time' observation of the extent of tissue damage is feasible.     

A fundamental study on hyper-thermal neutrons for neutron capture therapy

The utilization of hyper-thermal neutrons, which have an energy spectrum with a Maxwellian distribution at a higher temperature than room temperature (300 K), was studied in order to improve the thermal neutron flux distribution at depth in a living body for neutron capture therapy. Simulation calculations were carried out using a Monte Carlo code 'MCNP-V3' in order to investigate the characteristics of hyper-thermal neutrons, i.e. (i) depth dependence of the neutron energy spectrum, and (ii) depth distribution of the reaction rate in a water phantom for materials with 1/v neutron absorption. It is confirmed that hyper-thermal neutron irradiation can improve the thermal neutron flux distribution in the deeper areas in a living body compared with thermal neutron irradiation. When hyper-thermal neutrons with a 3000 K Maxwellian distribution are incident on a body, the reaction rates of 1/v materials such as 14N, 10B etc are about twice that observed for incident thermal neutrons at 300 K, at a depth of 5 cm. The limit of the treatable depth for tumours having 30 ppm 10B is expected to be about 1.5 cm greater by utilizing hyper-thermal neutrons at 3000 K compared with the incidence of thermal neutrons at 300 K.     

Hollow-core photonic-crystal fibres for laser dentistry

Hollow-core photonic-crystal fibres (PCFs) for the delivery of high-fluence laser radiation capable of ablating tooth enamel are developed. Sequences of picosecond pulses of 1.06 microm Nd:YAG-laser radiation with a total energy of about 2 mJ are transmitted through a hollow-core photonic-crystal fibre with a core diameter of approximately 14 microm and are focused on a tooth surface in vitro to ablate dental tissue. The hollow-core PCF is shown to support the single-fundamental-mode regime for 1.06 microm laser radiation, serving as a spatial filter and allowing the laser beam quality to be substantially improved. The same fibre is used to transmit emission from plasmas produced by laser pulses on the tooth surface in the backward direction for detection and optical diagnostics.     

四肢远近端顺行双筋膜皮下蒂皮瓣修复四肢缺损

目的探讨应用远近端顺行双筋膜皮下蒂皮瓣修复四肢近端缺损的临床效果。方法自2005年8月至2007年8月，应用远近端顺行双筋膜皮下蒂皮瓣修复四肢病变组织切除术后的皮肤缺损患者36例。按病变组织的形状将其行圆形或椭圆形切除，于缺损的一侧设计、形成以皮瓣基底部皮下组织为蒂或以皮瓣两侧皮下组织为蒂的皮瓣，皮瓣最大宽度小于或等于缺损直径，长度约为缺损直径的1．5-2．0倍，推进覆盖缺损部位。结果36例患者的皮瓣全部成活。术后随访3个月至1年，瘢痕不明显，皮瓣颜色与周围正常皮肤相近，形态较好。结论此方法具有操作简单、皮瓣的血运可靠及转动灵活、愈后切口瘢痕不明显等优点，对于因直接缝合张力大的四肢皮肤缺损的修复，是比较理想的手术方法。     

Focal nodular hyperplasia-like lesion of the liver in a child previously treated for nephroblastoma

Described herein is the case of an 8-year-old boy who developed a hepatic nodular lesion after having received anti-neoplastic therapy for nephroblastoma. Histological examination of the excised specimen indicated a disordered arrangement of hepatic components with hemangioma-like features. This case was diagnosed as a variant of focal nodular hyperplasia. It is speculated that this hepatic lesion is a late complication of treatment for nephroblastoma and might develop from congenital malformative area of the liver.     

Experimental verification of improved depth-dose distribution using hyper-thermal neutron incidence in neutron capture therapy

We have proposed the utilization of 'hyper-thermal neutrons' for neutron capture therapy (NCT) from the viewpoint of the improvement in the dose distribution in a human body. In order to verify the improved depth-dose distribution due to hyper-thermal neutron incidence, two experiments were carried out using a test-type hyper-thermal neutron generator at a thermal neutron irradiation field in Kyoto University Reactor (KUR), which is actually utilized for NCT clinical irradiation. From the free-in-air experiment for the spectrum-shift characteristics, it was confirmed that the hyper-thermal neutrons of approximately 860 K at maximum could be obtained by the generator. From the phantom experiment, the improvement effect and the controllability for the depth-dose distribution were confirmed. For example, it was found that the relative neutron depth-dose distribution was about 1 cm improved with the 860 K hyper-thermal neutron incidence, compared to the normal thermal neutron incidence.