射频消融对较大肝肿瘤治疗范围与布针方案计算的研究

目的 探讨超声引导射频消融（radio-frequency ablation,RFA）治疗肝肿瘤中治疗范围与射频针伞径、布径次数之间的关系，设计较准确的布针定点定位方法。方法 将肿瘤模式化为类球体，根据球体覆盖原理建立数学模型，应用正棱柱法及正多面体进行推导计算，获得治疗范围与射频针伞径、布针次数的关系式。根据RFA治疗原则消融范围须超越肿瘤周边0.5cm以上，按照覆盖类球体肿瘤的计算结果，采用伞径5.0cm的射频针，治疗4.1～4.3cm的肿瘤须用正四面体法至少布针4个点，治疗4.4～5.6cm的肿瘤用正棱柱法至少布针5～8个点，5.7～6.0cm的肿瘤用三层重叠法至少布针12个点，方能达到较彻底覆盖灭活肿瘤的效果。结果 应用上述治疗方案对32个3.5～6.6cm的病灶设计布针进行RFA治疗，肿瘤灭活率达84.4%。结论 肿瘤类球体治疗计算方案对RFA治疗中不能一次覆盖的较大肿瘤，可提供分区布针方案，有助于提高RFA对肝癌的灭活率，减少肿瘤残留复发。     

超声引导下不同布针策略在肝癌射频消融治疗中的临床价值

目的 探讨超声引导下不同布针策略在肝癌射频消融治疗中的临床价值.方法 拟对62例肝癌(经临床确诊或经病理确诊)患者62个病灶行超声引导下经皮射频消融治疗,将患者随机分为2组:A组从肿瘤中央开始布针,顺序向周边延伸;B组从肿瘤周边开始布针,顺序向中央延伸.治疗后3个月复查彩超或增强CT,评价病灶消融效果.结果 两种布针方法消融治疗有效部分差异无统计学意义(P＞0.05),但是A方法消融效果好的部分多于B方法,有更多的病灶完全毁损,两者差异有统计学意义(P＜0.05).结论 两种不同布针方法RFA治疗肝癌均有效,但从肿瘤中央开始布针,顺序向周边延伸的方法优于从肿瘤周边开始布针,顺序向中央延伸的方法.     

超声对RFA治疗胆囊旁肝癌的胆囊安全性观察

目的:探讨超声引导下经皮肝射频治疗胆囊旁肝癌对胆囊安全性及胆囊旁肝癌治疗的新途径。方法:11例患者在术前、术后超声检查,观察胆囊的变化。结果:经皮肝穿RFA治疗胆囊旁肝癌可致胆囊非常轻微的热烧灼,但无需处理,5～7天恢复正常。结论:超声引导下经皮肝穿RFA治疗胆囊旁肝癌疗效确切,对胆囊是安全的,虽可导致胆囊轻微炎性改变,但对胆囊的影响为自限性。     

超声引导冷循环射频消融治疗肾癌的研究

目的探讨超声引导(UG)冷循环射频消融(RFA)治疗肾癌的价值。方法对46例不能行手术切除的先天或后天性孤立肾及肾功能不全患者的46个肾肿瘤,在UG行肿瘤RFA治疗,其中左肾肿瘤22例,右肾肿瘤24例,肿瘤直径1.5～5.2cm,平均3.6cm。在UG将射频针穿刺至肿瘤底部行RFA治疗,根据肿瘤大小行多针多点、交叉重叠法RFA治疗。对CDFI显示肿瘤有供血动脉及血供丰富者的肿瘤,先选择高温模式封闭肿瘤供血动脉及肿瘤内血供丰富区,再行RFA,直至消融气化范围覆盖全部肿瘤为止,每点治疗时间为6～12min,治疗结束后选择高温模式封闭针道,防止出血或肿瘤沿针道种植。治疗后1、3、6、12个月行对比增强CT (CECT)复查,评估疗效,如发现肿瘤残留再行追加治疗。结果 46例肾肿瘤患者的46个肿瘤均顺利行RFA治疗,治疗后1～3个月CECT复查,肿瘤完全灭活为80.4%(37/46),肿瘤残留19.6%(9/46),对肿瘤残留者均行再次RFA治疗,治疗后9～24个月肿瘤局部进展7例17.4%(7/46),对肿瘤局部进展患者均行再次RFA治疗。结论超声引导RFA治疗肾癌,能实时监视进针方向,穿刺成功率达到100%,选择多针多点立体定位法RFA治疗,经CECT复查肿瘤完全灭活成功率80.4%,且操作方便,并发症少,为不适合手术切除的肾肿瘤患者提供了一种新的安全有效的治疗方法。     

超声CT引导多点布针单极冷循环射频消融治疗周围型肺癌的对比研究

目的 评估超声和CT引导下多点布针单极冷循环射频消融(radiofrequence ablation,RFA)治疗周围型肺癌的疗效及安全性.方法 将60例周围型肺癌患者分成A、B2组.A组:超声引导组35例;B组:CT定位组25例,应用单极冷循环RFA系统治疗.治疗后1～3个月行增强CT (CECT)复查,观察肿瘤灭活情况,如有残留追加治疗;治疗后6个月行CECT复查,评估近期疗效;治疗后12～24个月CECT复查,评估远期疗效.结果 60例患者RFA治疗顺利,治疗后1～3个月行CECT复查,肿瘤未强化为66.7％ (40/60),部分强化为33.3％(20/60),其中A组11例,B组9例,对部分强化行再次RFA治疗.治疗后6～24个月行CECT复查,肿瘤体积较治疗前明显缩小71.7％ (43/60),肿瘤体积较前增大并部分强化28.3％ (17/60).2组比较差异无统计学意义P＞0.05.RFA治疗10 d后血清CYFRA21-1水平与治疗前比较,P＞0.05差异无统计学意义;治疗后20 d及30 d分别与治疗前比较CYFRA21-1水平明显下降,P＜0.05差异有统计学意义.结论 超声引导下多点布针RFA治疗毗邻胸壁周围型肺癌,穿刺成功率高,能实时观察进针方向,操作方便,并发症少,费用低,是一种安全、有效的治疗方法.     

超声引导下经皮肾脏肿瘤射频消融术的早期经验

目的:探讨超声引导下经皮射频消融(radiofrequency ablation,RFA)技术治疗肾脏肿瘤的有效性及安全性。方法:31例肾肿瘤患者接受RFA治疗,其中3例为姑息治疗,随访观察疗效及并发症。平均随访时间为24.6个月,随访方式以超声造影为主,增强CT或MRI为辅。结果:以肿瘤灭活为目标的28例肿瘤中,27例(96.4%)得到成功治疗,其中22例经1次RFA、4例经2次RFA、1例经3次RFA后达到完全消融。完全消融的27例肾肿瘤中,2例(7.4%)出现局部复发。肿瘤大小是影响RFA成功的重要因素(P=0.017),肿瘤直径≤3.5 cm可作为预测RFA成功的临界值(P=0.021),但肿瘤大小与是否出现局部复发并无明显关联(P=0.129)。此外,患者年龄、性别及肿瘤位置与肿瘤是否能完全消融或是否出现局部复发无明显相关。11例(35.5%)患者在RFA后出现自限性并发症,无严重并发症发生。结论:超声引导下经皮RFA能有效治疗直径≤3.5 cm的肾肿瘤,并发症发生率低,但长期疗效还需进一步观察。     

超声引导射频消融治疗肝脏恶性肿瘤

目的 探讨超声引导射频消融（RFA）对肝脏恶性肿瘤的治疗效果。方法 对原发性肝癌55例、肝转移癌37例,计92例、132个病灶行超声引导RFA治疗;肿瘤大小中位数为3.2cm(1.5-8.0cm)。89例经皮超声引导RFA术均在门诊进行,余3例行术中超声引导下RFA治疗,采用螺旋CT增强检查及其他方法综合评价疗效。结果 1d或1个月后增强CT检查,显示120个病灶被完全灭活,有效率达90.9%,其中有21例（22.8%)行第2-4次RFA治疗,1至3个月后CT显示85例（68.5%)肿瘤缩小,1例巨块型肝癌大出血,急诊手术中行RFA治疗止血成功,经3-16个月随访,目前89例存活,1例因手术、2例因合并食管静脉瘤出血死亡,较重并发症3例,1例损伤肝被膜致出血,经RFA止血成功;1例肝功能指标异常加重,出现黄疸、腹水;另1例肝管显著扩张,黄疸加重,行经皮肝胆管置管引流。结论 超声引导RFA对不同或不适宜手术切除的肝脏恶性肿瘤提供了有效的微创治疗手段。但选择适应证及重视操作方法仍是关键因素。RFA对肝肿瘤破裂出血可能为一局部止血的方法。     

超声影像在经皮射频治疗肾VX2肿瘤中应用体会

目的探讨超声影像在经皮集束电极射频消融肾肿瘤模型中的引导方法及应用价值。方法将27只新西兰大白兔在超声引导下经皮穿刺组织块悬液注射法建立肾VX2肿瘤模型，成模后超声影像观测肿瘤结节并确定穿刺点，行超声引导下经皮射频消融肿瘤结节，于治疗后观察肿瘤的生长情况和消融灶的位置、大小及声像图变化。结果27只兔形成31个肿瘤灶接受射频治疗。超声影像引导穿刺成功率1DO％；二维声像图显示19个消融灶电极针放置合理，病灶消融完全，12个病灶消融不完全，出现残余灶，均经病理解剖证实。4只兔出现周围脏器灼伤，3只兔出现针道转移。结论超声影像引导经皮射频消融肾脏肿瘤安全、有效，超声准确的术前定位、精确的术中引导和医师熟练的配合是操作成功的关键。     

射频消融治疗肝海绵状血管瘤36例分析

目的探讨B超引导经皮及腹腔镜下射频消融(Radio frequency ablation,RFA)治疗肝海绵状血管瘤的临床效果和应用价值。方法利用RF-2000射频治疗系统,在B超引导下经皮穿刺对30例肝海绵状血管瘤患者35个病灶及经腹腔镜下对6例肝海绵状血管瘤患者8个病灶进行射频消融治疗,并用彩色超声及CT检查以了解RFA的效果。结果每例患者均1次完成治疗,均无出血等并发症。随访6个月~5 a,所有病灶缩小均在50%以上,无一例复发。结论应用RF-2000射频治疗仪在超声引导下经皮或腹腔镜下热损治疗肝海绵状血管瘤,并发症低,安全性高,效果好,是肝脏血管瘤治疗的又一安全有效的微创治疗新途径。     

肝脏肿瘤经皮射频消融术后发生肿瘤针道转移的危险性分析

目的：回顾分析117例行经皮射频消融术（RFA）治疗的肝脏肿瘤患者,评价RFA治疗肝脏肿瘤后发生肿瘤针道转移的概率,并探讨某些危险因素与肿瘤针道转移之间的关系。材料与方法：2005年4月~2008年3月行RFA治疗的肝脏肿瘤患者共117例,评价其术后随访的CT资料,计数肿瘤针道转移病例,计算发生概率,评价相关的危险因素。结果：随访发现肿瘤针道转移5例,占所有患者的4.3%（5/117）,占所有行RFA治疗病灶的3.9%（5/128）。5例针道转移均发生在RFA后半年以内。结论：RFA治疗后发生肿瘤针道转移的概率很低。术后不进行射频针道的电凝处理及位于肝包膜下的肿瘤是发生肿瘤针道转移的危险因素。RFA术后半年内须密切复查注意肿瘤针道转移的发生。     

Electrode placements for transcutaneous electrical nerve stimulation.

Even though transcutaneous electrical nerve stimulation is gaining increasing acceptance as a noninvasive method of pain modulation, many professionals have not been adequately instructed in the many techniques involved in electrode placement. Alternative methods are presented that can be used when more commonly used methods fail to obtain satisfactory results. Anatomical and physiological considerations for determining appropriate electrode placement sites are stressed.     

冷循环射频消融治疗多灶性转移性肝癌的疗效评价

目的评价冷循环射频消融治疗多个病灶的转移性肝癌的效果.方法对20例病人的42个转移性肝癌灶进行了58次冷循环射频消融治疗.射频采用单极电极输出,单探头或集束探头(2～4个)组合,每个病灶治疗1～3次.结果治疗后肿瘤有不同程度缩小,完全坏死30个(71.4%),大部坏死12个(28.6%),无严重并发症.结论冷循环射频消融技术简单、安全、有效,可作为不能手术切除的多灶性转移性肝癌的微创治疗方法.     

Radiofrequency ablation of problematically located hepatocellular carcinoma: tailored approach

BACKGROUND: The challenge for radiofrequency ablation (RFA) of hepatocellular carcinomas (HCC) in problematic locations is that the outcome is limited due to insufficient ablation or injury of nearby structures. This study aimed to evaluate effective strategy and treatment results of RFA in these cases. METHODS: Ultrasound guided percutaneous RFA was performed in 326 HCC patients. Among them, 249 tumors in 215 patients located at liver periphery, including 54 adjacent to GI tract, 110 close to the diaphragm, 49 close to the gallbladder, and 36 tumors close to liver surface. The sizes of the tumors ranged 1.2-7.0 cm (average 3.7 +/- 1.3 cm). Individualized treatment strategy was established for tumors in various locations, including "artificial ascites", "lift-expand" electrode placement, "draw-expand" electrode placement, "Supplementary ablation", and "accumulative multiple ablations" techniques. Treatment outcome was compared with another 64 central-located tumors (control group) in the same patients. One-month post-RFA contrast CT was used to evaluate early necrosis rate of the treated tumors. RESULTS: Early tumor necrosis were obtained in 91.6% (228/249) of the problematically located HCC, including 90.7% (49/54) of the tumors adjacent to GI tract, 90.9% (100/110) near the diaphragm, 91.8% (45/49) by the gallbladder, and 94.4% (34/36) close to liver surface. The necrosis rate of control group was 98.4% (63/64), which was higher than the tumors close to diaphragm (P = 0.049). Local tumor recurrence was 8.4% (21/249), comparing with 3.1% (2/64) of the control group (P > 0.05). The 1-, 2- and 3-year survival rate of this group were 81.6%, 63.8%, and 53.6%, respectively. Major complications occurred in 3.2% (11/343) of the treatment sessions, including hemorrhage in two, nearby structure injury in five, and needle tract seeding in four patients. CONCLUSIONS: Individualized treatment strategy for problematically located HCC is helpful in improving RFA outcome and expanding the application range of the therapy.     

彩色多普勒血流显像对集束电极射频治疗肝癌的效果观察

目的;利用彩色多普勒显像技术评价肝癌集束电极射频治疗术的早期效果。方法：采用彩色多普勒血流显像仪对２８例肝癌患者,集束电极射频治疗术前后１周肿瘤内血流动力学变化进行观察。结果：集束电极射频治疗前２８例肝癌患者３８个结节中３１个可测及血流信号,以动脉脉混合血流供血为主,治疗后有血流的３１个肿块中１１个血流减少,１４个完全消失,肿瘤内Ⅱ￣Ⅲ级血供及动静脉双重供血明显减少,早期观察认为血流减少或消失与肿     

应用自然组织谐波和彩色多普勒血流显像技术评价集束电极射频治疗肝癌的早期效果

目的 ＮＴＨＩ及ＣＤＦＩ评价肝部射频治疗术早期效果。方法 应用ＮＴＨＩ和ＣＤＦＩ对行集束电极射频治疗肝癌的３５例患者４７个肿块治疗前后１周瘤体的形态学及血供进行观察。结果 射频术后１周,３５例患者４７个肿块中３１个体积缩小,９个 块大小变化不明显,７个肿块较术前增大。低回声肿块变成等回声或强问声肿块,强回声肿块无变化或变化不均质强回声。术前４２个肿块可测及血流信号,术后１９个血流减少,１４个完全消     

Complications of percutaneous ethanol ablation.

Percutaneous ethanol injection therapy performed with sonographic visualization is a steadily growing therapeutic method that can be used in the ablation of solid and cystic masses in a variety of anatomic locations. Ethanol has been used for many years as an angiographically administered agent for vascular embolization of tumors such as hepatic and renal neoplasms. It was first used as a percutaneously injected agent for the sclerosis of renal cysts. Local infiltration or intravascular injection of ethanol leads to cell death by causing cell membrane lysis, protein denaturation, and vascular occlusion. Because of the initial success in the sclerosis of renal cysts, percutaneously injected ethanol is now used in the ablation of hepatic cysts and solid tumors, such as hepatocellular carcinomas. As a treatment agent, ethanol combines the benefits of being widely available, inexpensive, efficacious, and relatively easy to administer. Optimal results require that the radiologist have considerable experience in ultrasonographic scanning techniques and facility with percutaneous needle insertion under real-time visualization. Alternatively, the radiologist may choose CT as a method to visualize needle placement. Percutaneous ethanol injection therapy usually is an effective alternative to conventional surgical resection of liver lesions and has a low complication rate. We present two patients in whom hypotensive complications occurred during percutaneous ethanol injection therapy and discuss the likely causative mechanisms.     

Imaging of hypoxia-driven gene expression in an orthotopic liver tumor model

The purpose of this study was to monitor hypoxia in an orthotopic liver tumor model using a hypoxia-sensitive reporter imaging system and to image enhanced gene expression after clamping the hepatic artery. C6 and RH7777 Morris hepatoma cells were transduced with a triple reporter gene (HSV1-tk/green fluorescent protein/firefly luciferase-triple fusion), placed under the control of a HIF-1-inducible hypoxia responsive element (HRE). The cells showed inducible luciferase activity and green fluorescent protein expression in vitro. Isolated reporter-transduced Morris hepatoma cells were used to produce tumors in livers of nude rats, and the effect of hepatic artery clamping was evaluated. Tumor hypoxia was shown by immunofluorescence microscopy with the hypoxia marker EF5 [2-(2-nitro-1H-imidazol-1-yl)-N-(2,2,3,3,3-pentafluoropropyl acetamide)] and the fluorescent perfusion marker Hoechst 33342, and by pO(2) electrode measurements. For tumor hypoxia imaging with the HRE-responsive reporter, both luciferase bioluminescence and [(18)F]2'-fluoro-2'-deoxyarabinofuranosyl-5-ethyluracil positron emission tomography was done, and the presence of hypoxia in Morris hepatoma tumors were successfully imaged by both techniques. Transient clamping of the hepatic artery caused cessation of tumor perfusion and severe hypoxia in liver tumors, but not in adjacent liver tissue. These results show that the orthotopic reporter-transduced RH7777 Morris hepatomas are natively hypoxic and poorly perfused in this animal model, and that the magnitude of hypoxia can be monitored using a HRE-responsive reporter system for both bioluminescence and positron emission tomography imaging. However, the severity of tumor ischemia after permanent ligation of the hepatic artery limits our ability to image severe hypoxia in this animal model.     

应用自然组织谐波和彩色多普勒血流显像技术评价集束电极射频治疗肝癌的早期效果

目的 NTHI 及CDFI 评价肝癌射频治疗术早期效果。方法 应用NTHI 和CDFI 对行集束电极射频治 疗肝癌的35 例患者47 个肿块治疗前后1 周瘤体的形态学及血供进行了观察。结果 射频术后1 周,35 例患者47 个肿块中31 个体积缩小,9 个肿块大小变化不明显,7 个肿块较术前增大。低回声肿块变成等回声或强回声肿块, 强回声肿块无变化或变化不均质强回声。术前42 个肿块可测及血流信号,术后19 个血流减少,14 个完全消失。结论 NTHI 和CDFI 对观察射频疗效有重要的意义。     

Electrograms from the Coronary Sinus in Acute Myocardial Infarction: Implications for Electrocardiographic Guidance of Pacing Catheters

Intracardiac electrocardiography has been reported to be the most reliable of the techniques used for guiding placement of transvenous pacing catheters. When a catheter electrode is in contact with the right ventricular apical endocardium, the intracardiac electrogram demonstrates marked ST segment elevation and, usually, a very large S wave. The case presented indicates that both of these features of the intracardiac electrogram should be sought since ST segment elevation alone may represent epicardial recording of an acute myocardial infarction when the catheter electrode is in the coronary venous system.     

Radiofrequency ablation of liver tumors: the role of microbubble ultrasound contrast agents

Radiofrequency ablation (RFA) is currently indicated for the treatment of primary and metastatic hepatic malignancies. Real-time ultrasound (US) is generally used during the procedure to guide electrode placement, but for evaluating the results of treatment, contrast-enhanced computed tomography and magnetic resonance imaging have traditionally been considered more effective. This view has changed, however, with the recent development of contrast-enhanced ultrasound (CEUS) (eg, using sulfur hexafluoride microbubbles), which can provide valuable information on the effects of RFA more rapidly and economically than computed tomography or magnetic resonance imaging without exposing the patient to ionizing radiation. In our center, CEUS is performed in patients with liver tumors before and immediately after RFA, in selected cases during the procedure as well, and in the follow-up. Between January 2003 and June 2005, we performed CEUS on 350 patients scheduled for RFA of primary or metastatic liver tumors. In 14 (13.4%) of the 96 patients whose disease was metastatic, CEUS revealed lesions that had been missed on the conventional US examination. In most of these cases, the result was a more complete treatment performed under CEUS guidance. In the remaining 2 (14%) of 14, the results of the examination allowed us to avoid subjecting the patient to useless treatment. In our experience, the use of CEUS also improved the management and follow-up of patients undergoing interstitial therapy.