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101.
探讨螺旋CT引导下射频热凝联合臭氧消融治疗腰椎间盘突出症日间手术的临床疗效。方法 回顾性收集2020年1月—2022年6月我院日间病房住院的137例腰椎间盘突出症患者的临床资料,所有患者均行螺旋CT引导下射频联合臭氧消融治疗日间手术。收集手术时间,术毕至出院时间,总住院时间,术前、术后1月、3月的疼痛数字评分(NRS),Oswestry功能障碍指数(ODI)评分,改良 Macnab评级和手术相关并发症,并进行术前与术后的对比分析。结果 所有患者在螺旋CT引导下穿刺成功率为100%,并在手术当日出院,平均手术时间为(35.55±10.44)min,平均术毕至出院时间为(58.36±25.26) min,平均总住院时间为(453.91±27.18)min。术后1、3月的NRS评分和ODI评分均低于术前;术后1、3月改良Macnab疗效评定标准有效率分别为86.13%、89.05%。所有患者均未有穿刺或治疗相关的并发症。结论 螺旋CT引导下射频联合臭氧消融治疗腰椎间盘突出症日间手术是可行的,其可降低腰椎间盘突出症患者的疼痛程度、改善日常功能障碍、安全性高,可在临床推广应用  相似文献   
102.
目的 探讨分析基于心脏磁共振特征追踪技术(FT-CMR)的心脏功能评估参数对心房颤动冷冻球囊消融患者治疗后复发的预测效能。方法 选取2019年6月至2020年12月收治的126例预行冷冻球囊消融术的心房颤动患者为研究对象,术前均进行心脏磁共振检查,根据术后6个月内患者有无复发将其分为窦性心律组72例和房颤复发组54例。比较两组患者左心房应变及应变率参数,采用FT-CMR评估患者心脏功能,并进行单因素、多因素logistic回归分析,探讨FT-CMR心脏功能评估参数对心房颤动冷冻球囊消融术后复发的预测价值。结果 房颤复发组患者女性、高血压、糖尿病、非阵发性心房颤动比例显著高于窦性心律组(P<0.05)。房颤复发组患者左心房总应变(Es)、左心房正向应变率峰值(SRs)、左心房被动应变(Ee)、心室舒张早期负向应变率峰值(SRe)、左心房整体纵向应变(PLAS)参数值低于窦性心律组(P<0.05)。Logistic多因素回归分析结果显示,性别(OR=3.511,95%CI:1.036~11.906)、PLAS(OR=1.089,95%CI:1.039~1.141)是心房颤动冷冻...  相似文献   
103.
目的 分析经皮射频消融(PRFA)与手术切除治疗直径≤3 cm原发性小肝癌的疗效。方法 选取2015年1月—2017年6月兰州市第二人民医院收治的原发性小肝癌患者78例。将36例接受PRFA治疗的患者作为观察组,另外42例行手术切除的患者作为对照组。采用全自动生化分析仪检测血清谷草转氨酶(AST)、谷丙转氨酶(ALT)、总胆红素(TBIL)水平,电化学发光全自动免疫分析仪检测血清甲胎蛋白(AFP)水平。结果 观察组手术时间、术中出血量、住院时间均少于对照组(P <0.05);观察组治疗前后AST、ALT、TBIL、AFP的差值均高于对照组组(P <0.05)。两组术后并发症比较,差异无统计学意义(P>0.05);两组治疗后1、2、3、5年的生存率和复发率比较,差异均无统计学意义(P>0.05)。结论 与手术切除比较,PRFA治疗直径≤3 cm原发性小肝癌可缩短手术时间,减少术中出血量,促进肝功能恢复,但两者术后并发症发生率、生存率和复发率接近。  相似文献   
104.
Two cases are presented where ablation of severely symptomatic ventricular arrhythmias not responding to medical therapy was accomplished with radiofrequency current application. After a routine programmed stimulation protocol, a quadripolar ablation catheter with a 4-mm tip was advanced percutaneously into the left ventricle in one case and into the right ventricle in the second case; and after precise pace mapping, the arrhythmogenic focus was successfully ablated using radiofrequency current. The postablation ambulatory recording revealed virtual eradication of ventricular ectopy in both cases. In conclusion, in severely symptomatic cases of "benign" ventricular arrhythmias, radiofrequency ablation offers an effective therapeutic alternative.  相似文献   
105.
Eight successive position reversals were given preoperatively to establish position reversal sets in rats. Six animals received septal lesions, six fronto-polar cortex ablations, and six normals served as a control group. During a series of eight postoperative reversals, rats with septal lesions committed significantly more errors and approach errors than normals while fronto-polar ablations had no detectable effect.  相似文献   
106.
Neural crest cells are thought to play a critical role in human conotruncal morphogenesis and dysmorphogenesis. Much of our understanding of the contribution of neural crest to cardiovascular patterning comes from ablation and transplantation experiments in avian species. Although fate mapping experiments in mice suggests a conservation of function, the functional requirement for neural crest in cardiovascular development in mammals has not been formally tested. We used a novel two component genetic system for the temporal-spatial ablation of neural crest in the mouse. Affected embryos displayed a spectrum of cardiovascular outflow tract defects and aortic arch patterning abnormalities. We show that the severity of the cardiovascular phenotype is directly related to the level and extent of neural crest ablation. This is the first report of cardiac neural crest ablation in mammals, and it provides important insight into the role of the mammalian neural crest during cardiovascular development.  相似文献   
107.
目的研究肥厚梗阻型心肌病患者经皮腔内室间隔心肌消融术对心电指标的影响。方法对50例肥厚梗阻型心肌病患者行经皮腔内室间隔心肌消融术,记录术前、术中和术后出现的心律失常类型,配对分析术前、术后心电指标的变化。结果术后与术前相比,QRS时限[(122.0±24.0)ms对(97.3±15.5)ms,P=0.000]明显延长,QTc[(469.3±32.2)ms对(434.3±41.5)ms,P=0.004]、PR间期[(169±26)ms对(162±24)ms,P=0.044]稍延长。术中心律失常发生率分别为:右束支传导阻滞70%(35/50),左束支传导阻滞8%(4/50),一过性AVB38%(19/50),频发室性早搏24%(12/50),短阵室性心动过速24%(12/50);未发生持续性室性心动过速和室颤。术后心律失常发生率分别为:右束支传导阻滞56%(28/50),左束支传导阻滞8%(4/50),交界区性心动过速4%(2/50),频发室性早搏16%(8/50),短阵室性心动过速8%(4/50)。无永久性起搏器植入及死亡病例。结论经皮腔内室间隔心肌消融术致心律失常的发生率高,右束支传导阻滞最为常见。严格选择适应证后谨慎地行PTSMA术是安全、可行的。  相似文献   
108.
Radiofrequency catheter ablation of the atrioventricular (AV) node or bundle of His was performed in 12 adult mongrel dogs. The aim was to create chronic incomplete AV block (first- and second-degree AV block) and to examine the histopathology of the ablated lesions. However, the late electrophysiological results (2 4 weeks follow up) were various: normal in 2 dogs, mild PR prolongation (< 50%) in 2 dogs, first-degree AV block (PR prolongation a 50%) in 2 dogs, second degree AV block in 2 dogs, complete AV block in 4 dogs. The maximally ablated area (%) of the atrioventricular conduction system in serial histologic sections from dogs with these conditions was 69%, 75%, 89.5%, 95% and 99.5%, respectively. The number of intact conduction cells at the maximally ablated site varied from 6 to 30 in the four cases of incomplete AV block. The mean ablated volume (%) of either the AV node or penetrating His bundle correlated roughly with the degree of AV block. The ablated lesions were well demarcated and almost replaced by dense fibrous tissue at 4 weeks. Interruption (3 dogs) or thinning (1 dog) of the endocardial elastic lamellae was detected, in association with endocardial thickening (mean 913 μm). Endocardial thrombi were found in 3 dogs (2 fresh, 1 organized). We conclude that radiofrequency catheter ablation does not cause severe complicated lesions. Several possible conditions for creating chronic incomplete AV block are discussed. Acta Pathol Jpn 41: 487–498, 1991.  相似文献   
109.
Ablative techniques, using standard defibrillators and commonly available cardiac catheters, have been applied to the His bundle and bypass tracts for the management of arrhythmias. We have done in vitro studies of the physical effects of these high energy electrical impulses delivered via different pacing electrodes. Unipolar impulses of 10 to 400 joules were delivered via three U.S.C.I. bipolar electrodes and three Vitatron Helifix electrodes immersed in Ringer's solution. The effects were recorded on 35 mm still film, video tape, and high speed cine film. Pressure, voltage, and current were measured. The U.S.C.I. bipolar electrodes and the Vitatron Helifix electrodes safely withstood repeated delivery of 400-joule impulses which produced similar flash shapes. Each took the form of an incandescent, spherical "fire-ball" centered around the exposed electrode surface. The mean diameters of the "fire-ball" for 10 to 400 J using the U.S.C.I. electrodes were 5-24 mm and 3-20 mm for the Helifix catheter electrodes. Peak pressure excursions of over an atmosphere were observed 3 cm from the electrode tips. Higher pressures, lower voltages, and larger currents occurred using the U.S.C.I. pacing lead. The simple, 35 mm time exposure technique showed that at low energies the flashes appeared to emerge in a retrograde manner from the U.S.C.I. catheters and more distally from the Helifix electrode. This suggested that the latter might be more effective with lower energy impulses. It is concluded that lower energies should be used to take full advantage of the active fixation electrode.  相似文献   
110.
目的 在肺癌微波消融治疗中探究基于CT的三维数字化导航技术的应用价值。方法 回顾性分析我院收治的92例肺癌患者,随机进行三维数字化导航微波消融或传统CT引导下微波消融,分为三维导航组和传统组,依据肿瘤位置、大小(最大径差值≤2 mm)及微波消融条件不同两两配对,共46对,比较2组手术时间、微波针穿刺次数、CT剂量指数、术中并发症发生率、术后病灶控制情况。结果 三维导航组与传统组的手术时间分别为(30.07 ± 6.36)min、(47.20 ± 9.65)min、穿刺次数分别为(1.72 ± 0.69)次、(7.13 ± 3.00)次、CT剂量指数分别为(11.16 ± 2.20)mGy、(26.67 ± 8.72)mGy、术中并发症发生率分别为10.87%、34.78%,以上3个指标三维导航组均低于传统组,三维导航组治疗有效率(93.48%)高于传统组(71.74%),差异均有统计学意义(P < 0.05)。结论 CT引导下利用三维数字化导航技术行肺癌微波消融治疗,使介入穿刺手术的操作更加精准安全。  相似文献   
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