【作者】 郑龙坡；

【导师】 蔡郑东； 纪方；

【作者基本信息】 第二军医大学 ， 外科学， 2007， 硕士

【摘要】 目的:1、评价CT定位引导下经皮穿刺射频消融技术微创治疗骨样骨瘤临床应用的可行性和临床疗效分析。2、应用热力学的有限元方法研究骨组织热传导的三维空间分布情况。3、探讨CT引导下经皮穿刺射频消融术在骨肿瘤治疗中的应用前景。方法:1、临床选取42例骨样骨瘤患者,年龄13~46岁,平均23.6岁;病灶在股骨上的17例,胫骨13例,骨盆7,肱骨3例,跟骨1例,椎体1例。对所有患者在腰麻或臂丛麻醉下行CT定位引导经皮穿刺射频消融术。术中CT扫描层厚为1~3mm,射频消融参数设定为4~6分钟,治疗温度90度,射频电极有效治疗直径1.5cm,所有电极都准确插入瘤巢中心。术前、术后进行MRI病灶扫描,进行影像学对比。视觉模拟标度尺(VAS)作为临床疗效评定参数,进行统计学分析,随访6~24月。2、参考生物力学有限元模型建立方法建立人体胫骨近端三维热力学有限元模型。选取新鲜牛胫骨上段15cm,应用德国西门子公司LightSpeed 16排螺旋CT沿人体横断面以层厚2mm扫描胫骨近端。扫描图片以DICOM格式输出,并通过自编程序转存为JPG格式。运用同济大学生物医学工程研究所实验室编写的数字图像处理程序处理CT图像,进行点云采集。将采集的点云文件输入逆向工程软件Geomagic进行实体模型构建。将从Geomagic软件里生成的实体模型IGES文件导入到有限元分析软件Ansys 9.0中去,构建热力学有限元模型。进行三维热力学有限元模型的传热计算,模型骨结构外表面设定为人体温度37℃,骨内指定部位假设有15mm直径球形区域热源,温度为90℃,在该条件下执行稳态计算。结果:1、所有患者术后住院24小时观察并行抗感染治疗,术后三天内有疼痛症状,给予口服非甾体类抗炎药物三天后停药,术后一周疼痛症状明显减轻,术后一月随访疼痛基本消失,随访6~24月无复发。术后一月复查MRI影像学有明显改变。VAS评分明显降低,有显著统计学意义(P<0.01)。2、距离热源不同距离的横截面温度分布等值线密度不同,越接近电极,等值线越密集,且呈不规则椭圆形。在胫骨矢状面上,越靠近消融中心的温度分布等值线越密集,越远越稀疏,且呈不规则椭圆形。结论:1、CT定位引导下经皮穿刺射频消融治疗骨样骨瘤是一种简单、微创、安全高效的技术。术中需要精确定位和多科室协作。2、越靠近热源所在的中央骨髓,热力学等值线分布越密集,温度梯度越大;越靠近偏离热源的周围骨皮质,热传导降低越明显,温度梯度越小。消融范围的大小与电极针暴露长度和空间布针位置密切相关。在骨组织中,整个热力场围绕消融电极呈不规则椭圆球形分布。3、射频消融技术在骨肿瘤治疗方面有广阔的应用前景,期待进一步的基础和临床试验。更多还原

【Abstract】 Objective1. To evaluate computed tomography (CT)-guided radiofrequency (RF) ablation as a minimally invasive therapy for osteoid osteoma with regard to technical and clinical success and clinical analysis of the feasibility and clinical application.2. Use thermodynamic finite element method to study bone conduction heat 3D spatial distribution.3. To discuss the application prospects of CT-guided percutaneous radiofrequency ablation in the treatment of bone tumors.Methods1. Forty-two patients (age range, 13~46 y; mean age, 23.6 y) with osteoid osteomas (femur, n = 17; tibia, n = 13; pelvis, n = 7; humerus, n = 3; calcaneus, n = 1; vertebral body, n = 1) were treated with CT-guided RF ablation. Percutaneous therapy was performed with use of brachial plexus block or spinal anesthesia. After localization of the nidus with 1–3-mm CT sections, osseous access was established with either a 3.0-mm coaxial drill system(made by us) or an 12-gauge cooker needle. RF ablation was performed at 90°C for a period of 4–6 minutes with use of a rigid RF electrode with a diameter of 1.5 mm. The procedures were regarded as technically successful if the tip of the RF electrode could be placed within the center of the nidus and could be heated to the desired temperature. Preoperative and postoperative MRI scanning and contrast for Image. Clinical success of treatment was defined as permanent relief of pain and return to normal function without additional treatment. Visual Analog Scale Scale (VAS) as a clinical evaluation parameters. 6~24 months follow-up.2. Reference biomechanical finite element modeling method to establish human proximal tibial 3D finite element model of thermodynamics. A 15-centimeter-long fresh cow upper tibia is selected. Application of the German Siemens products LightSpeed 16 spiral along with human cross-sectional thickness 2mm into CT Scanners. Scanning photos DICOM format output, and through writing procedures for transfers JPG format. Use Tongji University Institute of Biomedical Engineering Laboratory prepared the digital image processing procedures CT images, point cloud acquisition. Acquisition of the file input point cloud reverse engineering software Geomagic entity model construction. Lane will Geomagic software generated solid model IGES files into the finite element analysis software Ansys 9.0 to construct finite element model of thermodynamics. Thermodynamic 3D finite element model of heat transfer, the model appearance bone structure set to body temperature(37℃). Bone designated area assumption 15mm diameter spherical regional heat, the temperature is 90℃, in the steady-state condition for the implementation of calculation.Results1. Parallel observed in all patients 24 hours after anti-infection treatment. After three days with pain. Non-steroidal anti-inflammatory drugs were given orally for three days after withdrawal. One week after treatment to alleviate pain symptoms. The pain disappeared in one month and were no recurrence follow-up 6~24 months. Postoperative MRI changed significantly in one month review, and VAS score decreased significantly. There was a significant (P <0.01).2. Different distance from the source of the cross-section of the temperature distribution density of different contours, the closer electrode, isogram more intensive, and irregular oval. Tibia in the sagittal plane, the more smiles around the temperature distribution certer isogram more intensitive, the more the farther sparse, and irregular oval.Conclusions1. CT-guided percutaneous RF ablation is a simple, minimally invasive, safe and highly effective technique for treatment of osteoid osteoma. Thus need for more accurate positioning and Multi-department cooperation.2. Vietnam close to the heat of the central marrow, thermodynamics isogram more intensive distribution, the greater the temperature gradient. Vietnam close to the heat source from the surrounding bone cortex, heat conduction lower, the smaller the temperature gradient. Ablation of the size and length of exposure needle alectrode and the space needle is closely related to the location.3. Radiofrequency ablation has a wide range of potential applications on the treatment of bone tumor. Which expects further basic and clinical trials.更多还原