高风险肝癌经皮热消融治疗中的辅助技术

随着医疗设备的发展和技术的进步,经皮热消融已成为肝癌治疗领域不可或缺的重要手段,超声是最常用的热消融引导技术,在因多种不利因素导致常规超声显示不清肝癌病灶或病灶位于极易引起严重并发症的危险部位时,经皮热消融在肝癌治疗中的应用范围受到限制。近年来一些新的辅助技术被用于克服这些高风险或困难因素,已取得了良好疗效,扩大了热消融在肝癌治疗中的适应症。本文就近年来在超声引导下对高风险肝癌进行经皮热消融治疗时所使用的辅助技术进行综述。     

超声引导下微波消融治疗甲状旁腺功能亢进的应用价值

目的 研究超声引导下经皮微波消融治疗继发性甲状旁腺功能亢进的临床应用价值。方法 从2019年1月—2022年2月临沂市中心医院血液透析中心收治的,符合入选标准的尿毒症继发甲状旁腺功能亢进患者48例。微波消融前使用彩色多普勒超声诊断仪、超声造影、放射性核素等检查评估患者情况。在超声引导下实施增大的甲状旁腺微波消融。术中行超声造影判断消融是否彻底。对比患者术前、术后1天、1周、3个月、6个月血清甲状旁腺激素(Parathyroid Hormone, PTH)、血清钙、血清磷的浓度,并对随访获得的数据进行统计学分析。结果 共完成甲状旁腺消融67枚,均完成规定时间的随访,所有患者术后PTH、血钙、血磷浓度同术前相比,呈明显下降趋势,差异有统计学意义。结论 超声引导下经皮微波消融治疗继发性甲状旁腺功能亢进效果明显,对临床有重要的应用价值。     

肝癌微波消融仿真与手术计划系统研究进展

微波消融作为一种微创热消融技术,在肝癌治疗中具有广阔的应用前景。随着医学影像学技术的不断进步,肝癌微波消融技术也在不断完善。微波消融仿真计算以及基于三维可视化技术的消融手术计划系统在微波消融仪器技术的改进、消融手术计划、消融效果预测和疗效评估等方面发挥着越来越重要的作用。本文针对微波消融仿真方法和基于三维可视化技术的手术计划系统的研究进展进行了综述。     

结直肠癌肝转移的物理消融治疗及三维可视化技术的应用

结直肠癌肝转移是临床常见的疾病,但多数已失去手术切除的机会。随着结直肠癌肝转移的治疗方式和理念不断更新,多学科综合治疗已经成为规范。近年来,采用物理消融的手段成为了手术不能切除的病灶局部治疗的重要措施。采用三维可视化技术能进一步提高消融的精准性。本文就近年来结直肠癌肝转移的物理消融技术以及三维可视化技术的应用进行综述。     

集超声影像引导于一体的微波消融系统设计

本文设计了一种集超声影像引导的微波消融治疗仪,包括硬件系统的设计和治疗软件的设计。其中硬件系统负责实现微波消融、超声信号采集、消融天线水冷循环、温度采集等功能;治疗软件在实现精准治疗的同时还包含了超声图像监控的功能。本文将超声影像引导功能融入微波消融治疗仪当中,对实现微波消融的精准治疗具有较大意义。经实验验证,该系统输出功率误差小于3%,能够满足0-150W、0-30min的任意消融剂量选择,软硬件通讯顺畅,超声图像显示清晰,超声影像引导功能能够顺利引导消融天线到指定区域,实现超声导航、消融治疗以及术中消融区域温度监测和超声图像的采集。     

一种新型医疗辅助机器人的研究与分析

超声引导下的肿瘤热消融治疗操作对定位精度要求较高,同时手术器械相对单一、器械运动轨迹相对简单,适合于机器人应用;文中的医疗辅助机器人系统共有7个自由度,由于采用了轻量化技术,体积小、质量轻、定位精度高。因此,除了可以让手术变得更加的科学与可控外,还可以提高手术的稳定性与定位精度,增加医生的操作范围。适合在临床上进行广泛应用。     

介入导航机器人在肝肿瘤消融术中的应用研究

随着医学成像技术的大力发展,众多学者提出了使用穿刺导航机器人进行精准、安全、可靠的肝肿瘤微创热消融治疗。为归纳总结近年来介入导航机器人在肝肿瘤热消融术中的应用,本文分别阐述了基于医学影像引导的导航机器人系统和术中导航定位方法,并归纳总结了每种方法的适用性和局限性。     

超声引导下经皮激光消融甲状腺实性结节安全性及近期疗效评价

目的:探讨甲状腺实性结节采用超声引导下激光消融治疗的安全性及近期疗效。方法 :对45例甲状腺结节患者57枚结节行在超声引导下采用激光消融,术后1、3、6个月观察甲状腺结节缩小率及其血流信号变化。结果 :57枚甲状腺实性结节消融后经超声造影检测全部显示丧失血供,且原结节范围被消融区完全覆盖;术后随访表明结节均表现出不同程度的减小(P<0.05),完全消融率达94.74%。除1例患者出现颈部疼痛外,其他患者均未发生严重的颈部气管和食管损伤、喉返神经损伤或是颈部肌肉损伤导致的颈部外形改变和运动障碍。结论 :对甲状腺结节患者采用超声引导下激光消融治疗具有微创、安全、高效的特点,不影响甲状腺功能。     

微波消融技术进展综述

微波消融治疗技术具有微创、痛苦小、操作简便、可反复施行、疗效确切等优点,为肿瘤治疗提供了一种新途径,成为当前研究热点,在理论研究、实验研究和临床应用方面得到了广泛的关注。本文就首先阐述了微波消融机理,讨论微波消融的温度场、微波参数影响及消融天线设计等关键技术的研究进展,对微波消融在肺癌、肝癌、肾癌、子宫肌瘤、甲状腺癌等方面的临床应用研究现状进行了综述,最后讨论了微波消融技术面临的主要问题及发展方向。     

难加工材料精密切削技术研究

随着材料科学和先进制造技术的发展,难加工材料以其优良的物理机械性能在现代高技术行业的诸多领域得到越来越广泛的应用。针对难加工材料的结构特点,分析了难加工材料的切削加工特性,综述了硬切削加工、超声辅助切削加工、激光加热辅助切削加工及热超声辅助切削加工的国内外研究进展,并指出了精密切削应用于难加工材料切削加工时存在的问题及进一步的研究方向。     

Interstitial hyperthermia

The effectiveness of hyperthermia as a treatment modality for cancer continues to gain popularity in the medical community. One of the disappointing findings has been the inability to deliver uniform thermal doses to tumor volumes. This inability to heat certain tumors is due to a variety of physical and physiologic phenomena. To increase the ability of heating tumors, local interstitial techniques have been developed that are proving to be safe and effective. These techniques employ implanted microwave or radiofrequency antennae for the delivery of local thermal doses. Recently, investigations into the placement of interstitially located ferromagnetic seeds for local hyperthermia have also been conducted. The seeds can be heated by delivery of a high-wattage RF magnetic field to the implanted volume by an external source after implantation. The tissue surrounding the ferromagnetic implant is heated by conduction of heat away from the implanted seeds. While these techniques have been effective, further development of the instrumentation for interstitial therapies is continuing. These developments will include the application of specific control circuitry for delivery of accurate thermal doses.     

在线分析样气除湿新技术的应用研究

样气处理系统技术是在线气体分析系统的核心和关键技术[1]。在线样气处理技术的重点和难点是样气的除湿和除尘处理。样气的除湿处理有几种传统方法,已不同程度地被工程界认可,但从技术发展的角度看,仍有一定局限性。从提高系统品质、延长系统使用寿命周期的要求来看,仍有提高除湿技术水平和效果的必要。本文在综合分析样气除湿技术现状和总结工程实践经验的基础上,重点介绍样气除湿技术的创新及应用。     

Application of microwave spectroscopy to chemical analysis.

Traditional analytical techniques have been sucessfully employed on a great variety of systems for identifying stable reaction products as well as for purity analysis and reaction efficiency. However, most analytical techniques generally can only be applied to "well-behaved" chemical systems. Since gas phase reaction products do not always follow the "well-behaved" guideline, an alternate analytical tool, such as microwave spectroscopy, could prove beneficial for analyzing such systems and may well provide some new routes to synthetic chemistry. A general review of the present state-of-the-art for applications of microwave techniques to analytical studies will be presented. An attempt will be made to describe the limitations and advantages of microwave spectroscopy for probing chemical systems for product identification and for optimization of the efficiency of gas phase chemical reactions. As an illustration, some recent results obtained in our laboratory on the complex pyrolytic decomposition reactions of ethylamine will be described. Further examples of possible applications will be taken from typical industrial processes that employ vapor phase chemical synthesis techniques.     

A probe to estimate the local fuel concentration in spark ignition engines: design and validation study of catalytic hot wire probe

A catalytic hot wire probe (CHWP) technique has been developed to estimate the local fuel concentration near the spark plug of a spark ignition engine. Knowledge of this local concentration is highly useful in studying the combustion process. The small fuel concentration variation is measured by superimposing a catalysis effect in the thermal balance of the hot wire. Various parameters such as pressure, temperature and sampling velocity have been tested for their effect on the hot wire catalytic response.To validate this CHWP technique, local fuel concentration was also measured by two optical diagnostic techniques: planar laser-induced fluorescence (PLIF) and fuel/air ratio laser-induced exciplex fluorescence (FARLIEF). Comparison with PLIF measurements shows good agreement, and the capabilities and limitations of both techniques. With the FARLIEF/CHWP study, we can characterise the time and spatial variation of the fuel/air ratio in the vicinity of the spark plug in the gasoline direct injection engine.     

FEM based simulation of the pulsed laser ablation process in nanosecond fields

For the pulsed laser ablation in nanosecond fields, the key physical phenomenon of the removing process is thermal evaporation. For the process optimization of the nano-second laser ablation, it is essential to set up effective simulation that can reflect material absorption coefficient, energy intensity of laser, laser pulse shape, and so forth. In this research, material ablation in nano-second region is simulated by using a finite element method (FEM) commercial package and its result has been compared with experiment results focused on the difference in the ablation depth and its shape occurred after each laser pulse hitting. Finally, the effect of the parameter variation on the ablation process has been verified.     

切向气流作用下激光辐照对尼龙材料的热烧蚀规律

为了研究切向气流对激光毁伤低慢小目标的影响,采用仿真分析和实验相结合的方法研究了在激光辐照典型低慢小目标材料尼龙66过程中切向气流对激光烧蚀作用的影响。建立了激光烧蚀尼龙的简化物理模型,利用红外热像仪分别研究了1.5s和4s两个时刻激光辐照下尼龙材料的温度场分布和烧蚀形貌,并与无气流条件下的结果进行对比。实验表明,切向气流对激光烧蚀尼龙材料过程的影响主要分两个阶段,在辐照前段时间切向气流减缓了激光辐照下尼龙66材料的温升,抑制了激光对尼龙材料的烧蚀作用;但随着温度的升高,热分解产物增多使激光屏蔽作用增强,切向气流减轻了目标材料表面热分解产物对激光的衰减,并为尼龙材料的氧化烧蚀提供更多氧气,促进了烧蚀作用。最后对切向气流下激光烧蚀尼龙的过程进行了ANSYS仿真,实验结果和仿真结果基本一致,从而验证了理论的可靠性。     

Cost optimization of process tolerance allocation-a tree based approach

Tolerance transfer techniques are used extensively for allocation of tolerances for each machining operation in the process sequence, and hence are used to coordinate the process planning and the design activities in the evolution of a new product. This paper deals with an extended approach to allocate process tolerances based on a tree topology called technologically and topologically related surfaces (TTRS) and its subsequent extension to cost optimization. The benefit of this approach is that equations are generated explicitly with regard to tolerance transfer. These have been exploited by implementing the cost function in the generated explicit equations and subsequent optimization. The TTRS approach has been extended which scores over the limitations of some of the already existing techniques in that, it is optimal with respect to two factors namely, cost of producing the required tolerances, as also the process capability of the machines involved in producing the part. This technique has been proved practically feasible as it has been implemented in an industry. To enable a better view of the advantages of the approach, a comparative study with the existing techniques has been carried out in addition to a simulation using the Monte Carlo method.     

Composite Configuration Interventional Therapy Robot for the Microwave Ablation of Liver Tumors

The existing interventional therapy robots for the microwave ablation of liver tumors have a poor clinical applicability with a large volume, low positioning speed and complex automatic navigation control. To solve above problems, a composite configuration interventional therapy robot with passive and active joints is developed. The design of composite configuration reduces the size of the robot under the premise of a wide range of movement, and the robot with composite configuration can realizes rapid positioning with operation safety. The cumulative error of positioning is eliminated and the control complexity is reduced by decoupling active parts. The navigation algorithms for the robot are proposed based on solution of the inverse kinematics and geometric analysis. A simulation clinical test method is designed for the robot, and the functions of the robot and the navigation algorithms are verified by the test method. The mean error of navigation is 1.488 mm and the maximum error is 2.056 mm, and the positioning time for the ablation needle is in 10 s. The experimental results show that the designed robot can meet the clinical requirements for the microwave ablation of liver tumors. The composite configuration is proposed in development of the interventional therapy robot for the microwave ablation of liver tumors, which provides a new idea for the structural design of medical robots.     

基于全方程热流控制方法的典型舱段加热烧蚀试验研究

烧蚀型热防护是高超声速飞行器应用最广泛的一种热防护形式,高温烧蚀理论及相关计算分析方法尚不完善,无法通过计算给出精确的烧蚀热防护系统的热流和温度时序.全方程热流密度控制试验模拟结构的真实飞行历程,计及气动加热与结构热响应的耦合效应并实时测量迭代,成为烧蚀型热防护系统性能测试和研究的重要措施.本文以典型舱段为试验研究对象...