磁共振及超声引导HIFU消融子宫肌瘤的能量差异分析

发布时间：2018-05-08 21:23

本文选题：高强度聚焦超声 + T2WI信号强度值　；参考：《重庆医科大学》2014年硕士论文

【摘要】：子宫肌瘤是妇科常见的良性肿瘤，尤其在中年女性内有较高的发病率。除药物、传统手术、子宫动脉介入栓塞术外，目前高强度聚焦超声（High Intensity Focused Ultrasound，HIFU）消融技术也在临床广泛应用。其利用超声波在人体组织内良好的穿透性，从体外投射高能量超声波聚焦于体内的肌瘤病灶，使靶区组织温度升高并达到发生凝固性坏死的温度（≥60℃），实现体表无创伤、非侵入式的治疗。由于其生物学焦域面积小，在影像监控系统下能够依据病灶的范围，精确完整的消融病灶，且不会对周围正常组织细胞产生不可逆的损伤。除了应用最广泛的子宫肌瘤治疗，超声消融也被应用于骨肉瘤、肝癌、胰腺癌、前列腺癌等恶性肿瘤的治疗。目前研究发现，超声消融子宫肌瘤的疗效与肌瘤自身性质及治疗中参数有关。由于治疗中参数亦会受到肌瘤自身性质的影响，故肌瘤自身性质，如体积、位置、T2WI信号强度值等，都与超声消融子宫肌瘤疗效有着密切的关系，通过治疗前核磁共振成像（MRI）检查可以了解这些自身性质。而根据研究，MRI-T2WI信号强度值能够反映了肌瘤的组织学特性，提示肌瘤内成分如平滑肌细胞数量、结缔组织含量及血供情况的差异，而由于各种成分对于超声能量的穿透、吸收均不相同，因此，T2WI信号强度值与超声能量肌瘤内沉积关系密切。此外，目前临床上有磁共振引导下HIFU消融治疗（MRI guided HIFU，MRgHIFU）及超声引导下HIFU消融治疗（Ultrasound guided HIFU，USgHIFU）两种模式，两者区别主要在于影像学监控方式不同。目的研究通过MRgHIFU与USgHIFU消融子宫肌瘤的两组病例，采集治疗前肌瘤的MRI-T2WI信号强度值与消融治疗的超声能量，了解肌瘤组织T2WI信号强度值与消融所需超声能量的联系，并简要分析两组方式消融具有相同T2WI信号强度值的子宫肌瘤出现超声能量差异的原因。方法 1研究对象：2009年7月至2013年12月期间在上海市徐汇区中心医院完成HIFU治疗的纳入病例共56例,其中MRgHIFU治疗26例共30个肌瘤，USgHIFU治疗30例共37个肌瘤。 2治疗设备：磁共振引导下高强度聚焦超声系统：由1.5T磁共振（Avanto；西门子医疗）引导高强度聚焦超声肿瘤治疗系统（JM2.5；重庆海扶医疗科技股份有限公司）结合而成。超声引导下高强度聚焦超声系统：JC200型聚焦超声肿瘤治疗系（重庆海扶医疗科技股份有限公司）。 3治疗方法： 3.1MRgHIFU治疗中通过监测靶区及周围的温度变化。治疗方式为超声点辐照，通过逐步增加超声释放能量使组织内靶区温度升高到60℃及以上即表示实现消融，在超声辐照按计划完全覆盖离肌瘤的全部体积后停止治疗。 3.2USgHIFU治疗从肌瘤的最大层面开始，选择靶点置于肌瘤的深面后层离肌瘤后缘10mm处，然后沿肌瘤的后缘间隔5-8mm左右布置焦点进行后层的点辐照，使辐照区覆盖肌瘤的深面后层，以其形成相应的超声锥形声场覆盖整个肌瘤即可。 4治疗结果分析比较指标 4.1肌瘤体积消融率：通过公式：体积消融率=无灌注区体积（Non-Perfused Volume，NPV）/靶肌瘤体积×100% 4.2治疗时间和辐照时间：治疗时间是指第一次超声辐照开始至最末一次超声辐照之间的时间；辐照时间指超声治疗头投射能量的工作时间。 4.3超声能量和单位体积超声能量：超声能量（KJ）是指治疗过程中投射的超声总能量；单位体积超声能量（J/mm3），即能效因子，，是指每单位体积内投射的超声总能量，根据公式：单位体积超声能量=超声能量/无灌注区体积。结果 1.肌瘤自身性质：MRgHIFU组和USgHIFU组的平均体积分别为121.8±74.8cm3和114.7±53.9cm3（P0.05）；肌瘤的T2信号强度值为121.7±38.2和135.7±44.7（P0.05），均无差异性。 2.两组病例治疗参数：MRgHIFU组和USgHIFU组的平均肌瘤的消融体积分别为109.4±66.9cm3和101.5±50.0cm3，消融率分别为89.4±10.2%和93.9±8.7%，单位体积超声能量分别为4.71±3.4J/mm3和5.49±2.4J/mm3，超声辐照时间分别为1217±397s和1309±505s，治疗时间分别为132.5±37.4min和116.0±36.6min，以上数据两组间比较差异无统计学意义(P0.05)。MRgHIFU组和USgHIFU组平均超声能量释放功率分别为302.0±53.2W和377.8±32.2W，超声能量分别为374.9±173.7kJ和484.6±190.6kJ，以上数据两组间比较差异均有统计学意义。 3. MRgHIFU与USgHIFU两组病例的T2WI信号强度值与单位体积超声能量（能效因子）均有线性正相关关系(r＞0, P0.05)。结论 1.在两种不同引导方式下的HIFU治疗中，随肌瘤T2WI信号强度值增高，其消融单位体积超声能量增加，即消融肌瘤所需的超声能量增加。 2.由于影像监控设备及靶点分布传递能量方式的差异，最终导致了在消融相同T2WI信号强度值的肌瘤时，USgHIFU组所需的超声能量高于MRgHIFU组，但USgHIFU组对肌瘤组织的消融率更高，残余病灶组织更少。
[Abstract]:Uterine myoma is a common benign tumor in gynecology, especially in middle-aged women. Besides drugs, traditional surgery, interventional embolization of uterine artery, high intensity focused ultrasound (High Intensity Focused Ultrasound, HIFU) ablation technique is also widely used in clinical practice. Sex, projecting high energy ultrasound from the body in the body to focus on the body tumor lesion in the body to increase the temperature of the target tissue and reach the temperature of the coagulation necrosis (> 60 degrees C), to achieve the non invasive and noninvasive treatment of the body surface. Because of its small area of biological focal area, the accurate and complete ablation disease can be obtained under the range of the focus of the lesion. In addition to the most extensive use of uterine fibroids, ultrasound ablation is also used in the treatment of osteosarcoma, liver cancer, pancreatic cancer, and prostate cancer. The current study shows that the efficacy of ultrasound ablation of uterine myoma is related to the properties of the myoma and the parameters of the treatment. As the parameters of the treatment are also affected by the properties of the myoma, the properties of the myoma, such as volume, position and T2WI signal intensity, are closely related to the efficacy of ultrasonic ablation of uterine myoma. These properties can be understood by MRI examination before treatment. According to the study, the intensity of MRI-T2WI signals can be obtained. It reflects the histological characteristics of the myoma, indicating the differences in the number of smooth muscle cells, the content of connective tissue and the condition of blood supply in the myoma, and the absorption of the T2WI signal intensity is closely related to the internal deposition of the ultrasonic energy myoma. The two modes of HIFU ablation therapy (MRI guided HIFU, MRgHIFU) and HIFU ablation therapy (Ultrasound guided HIFU, USgHIFU) are guided. The difference is mainly due to the different methods of imaging monitoring.
objective
Two cases of uterine myoma were ablated by MRgHIFU and USgHIFU. The MRI-T2WI signal intensity value of the preoperative myoma and the ultrasonic energy of the ablation treatment were collected. The relationship between the T2WI signal intensity of the myoma tissue and the ultrasonic energy needed for the ablation was investigated, and the two groups of uterine myoma with the same T2WI signal intensity were briefly analyzed. The reasons for the difference of ultrasonic energy.
Method
1 subjects: 56 cases of HIFU treatment were completed in Central Hospital of Shanghai Xuhui District from July 2009 to December 2013, of which 26 cases with 30 myoma were treated with MRgHIFU, and 30 cases with 37 myomas were treated by USgHIFU.
2 treatment equipment: high intensity focused ultrasound system guided by magnetic resonance (MRI): 1.5T magnetic resonance (Avanto; SIEMENS) guided high intensity focused ultrasound tumor therapy system (JM2.5; Chongqing Haifu medical Polytron Technologies Inc) combined. Ultrasound guided high intensity focused ultrasound system: JC200 focused ultrasound tumor treatment system ( Chongqing Haifu medical Polytron Technologies Inc).
3 treatment methods:
In the treatment of 3.1MRgHIFU, the temperature changes in the target area and around the target area are monitored. The treatment method is irradiated by the ultrasonic point. The target area temperature in the tissue is increased to 60 degrees and above by gradually increasing the ultrasound release energy. The treatment is stopped after the complete coverage of the total volume of the leiomyoma according to the plan.
3.2USgHIFU therapy starts from the maximum level of myoma, and chooses the target to place the deep posterior layer of the myoma from the posterior edge of the myoma at the back edge of the leiomyoma, and then arrange the focus for the posterior layer of the posterior layer along the posterior margin of the myoma at about 5-8mm, so that the irradiated area covers the deep posterior layer of the myoma and forms the corresponding ultrasonic conical field to cover the whole myoma.
4 Analysis and comparison index of the results of treatment
4.1 volume ablation rate of myoma: through the formula:
Volume ablation rate = non perfusion volume (Non-Perfused Volume, NPV) / target volume volume * 100%
4.2 treatment time and irradiation time: the time of treatment refers to the time between the first ultrasound irradiation and the last ultrasound irradiation; the time of irradiation refers to the working time of the projection of the energy of the head by ultrasonic treatment.
4.3 ultrasonic energy and unit volume ultrasonic energy:
The ultrasonic energy (KJ) refers to the total ultrasound energy projected during the treatment; the unit volume ultrasonic energy (J/mm3), that is, the energy efficiency factor, refers to the total ultrasonic energy projected within each unit volume, according to the formula:
Ultrasonic energy per unit volume = ultrasonic energy / no perfusion volume.
Result
1. the average volume of myoma in group MRgHIFU and USgHIFU group was 121.8 + 74.8cm3 and 114.7 + 53.9cm3 (P0.05), and the T2 signal intensity of myoma was 121.7 + 38.2 and 135.7 + 44.7 (P0.05), no difference was found.
2. two groups of treatment parameters: the ablation volume of average myoma in group MRgHIFU and group USgHIFU was 109.4 + 66.9cm3 and 101.5 + 50.0cm3 respectively. The ablation rate was 89.4 + 10.2% and 93.9 + 8.7% respectively. The ultrasonic energy per unit volume was 4.71 + 3.4J/mm3 and 5.49 + 2.4J/mm3 respectively. The ultrasonic irradiation time was 1217 + 397s and 1309 + 505s, respectively. The differences were 132.5 + 37.4min and 116 + 36.6min. There was no significant difference between the two groups (P0.05). The average ultrasonic energy release power of the.MRgHIFU group and the USgHIFU group was 302 + 53.2W and 377.8 + 32.2W respectively. The ultrasonic energy was 374.9 + 173.7kJ and 484.6 + 190.6kJ respectively. The difference of the upper data two groups was statistically significant.
3. there was a positive linear correlation between the T2WI signal intensity of the two groups of MRgHIFU and USgHIFU and the ultrasonic energy (energy efficiency factor) of the unit volume (r > 0, P0.05).
conclusion
1. in the HIFU treatment under two different guiding methods, the ultrasonic energy of the ablation unit volume increased with the increase of the T2WI signal intensity of the myoma, that is, the increased ultrasonic energy needed for the ablation of the myoma.
2. because of the difference between the image monitoring equipment and the distribution of energy in the target distribution, the ultrasonic energy needed in group USgHIFU was higher than that of group MRgHIFU when the muscle tumor of the same T2WI signal intensity was ablated, but the ablation rate of the myoma tissue was higher in the USgHIFU group and the remnants of the lesion were less.

【学位授予单位】：重庆医科大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R737.33

【参考文献】