Motion artifact reduction with three-point ghost phase cancellation.

A novel method for "ghost" artifact suppression is introduced. It suppresses ghosts induced by motion in any direction, as well as other types of quasi-periodic signal modulation. Because it requires neither special hardware nor intensive data processing, it can be easily implemented on conventional magnetic resonance (MR) imagers. The method is based on the concept of decomposition of a ghosted complex image into a ghost mask and ideal image. A set of deliberately designed acquisitions are used to generate a set of ghosted complex images in which the ghost components are related in a simple manner. With use of equations describing image decomposition and ghost correlation, the ideal image can be calculated pixel by pixel. The ideal image obtained (representing the time-averaged spin-density distribution) is shown to be a truer representation of physical reality than the ghost-free image obtained with ordered phase encoding. In this technique, both interview and intraview effects are taken into account. The technique is also useful in simultaneously suppressing ghosts from multifrequency signal modulations such as respiratory and cardiac motions. The method was successfully tested with three time-interleaved, phase-encoding-order-shifted acquisitions. Experimental results have shown that it is a simple but effective technique.     

Analysis of the arterial blood pressure waveform using Fast Fourier Transform technique during left ventricular nonpulsatile assistance: in vitro study

The arterial blood pressure waveform is variable during left ventricular assistance. The aim of this study is to examine the correlation between the left ventricular assist device (LVAD) condition and the arterial blood pressure waveform in a fixed cardiac output condition using a mock circuit. This mock circulation loop was composed of an aortic compliance chamber, a left atrial compliance chamber, a pneumatic pulsatile pump as a native heart, and a rotary blood pump representing the LVAD with left atrial drainage. The Fast Fourier Transform technique was utilized to analyze the arterial blood pressure waveform and calculate the pulsatility index (PI) and the pulse power index (PPI). The PI and PPI decreased with the increase of the LVAD rotational speed, exponentially. There was a significant negative correlation between the PI, PPI, and the LVAD rotational speed, flow rate, and assist ratio. The best correlation was observed between the PPI and the assist ratio (r = 0.986). From this viewpoint, an ideal LVAD condition may be estimated from the pulsatility change of the arterial blood pressure waveform.     

中西医结合治疗急性病毒性心肌炎166例

观察生脉温胆汤加减配合西药治疗急性病毒性心肌炎的临床疗效。将249例患者随机分为治疗组166例和对照组83例。治疗组采用生脉温胆汤加减，每日1剂，水煎服。加用西药心肌营养剂。对照组采用心肌营养剂辅以抗心律失常药物治疗。两组均治疗3－6月后统计疗效。结果治疗组3月有效率31％，6月有效率92％；对照组3月有效率18％，6月有效率34．％。两组比较均有显著性差异（P＜0．05）。两组主要症状、体征、心电图恢复正常比较有显著性差异（P＜0．05）。说明生脉温胆汤加减配合西药治疗急性病毒性心肌炎效果满意。     

模拟定位机引导下经皮穿刺集束巨能刀射频治疗肺癌的临床应用

为了探讨局部麻醉和模拟定位机引导在集束巨能刀治疗肺癌的射频治疗的适应证、治疗效果以及并发症的预防和处理,采用0·5%普鲁卡因局部浸润麻醉,模拟定位机引导下经皮穿刺集束巨能刀治疗肺癌46例。CT显示条索状瘢痕残余11例,空洞形成或直径缩小32例,无变化1例,增大2例。治疗中患者均有不同程度的胸腔内热感及短时间内可以忍受的疼痛感。并发症包括气胸7例、皮下气肿5例、发热24例、咯血13例和慢性支气管炎急性发作4例。初步研究结果提示,集束巨能刀射频治疗周围型肺癌疗效满意,尤其适用于直径<3cm的肿瘤。局部麻醉配合全身止痛药物应用可以很好地解决治疗中的疼痛问题,与全麻相比还具有省时省力、费用低的优势;对于周围型肺癌,模拟定位机引导经皮穿刺定位与CT引导相比,同样准确、安全,但操作更为方便。     

老年高血压患者脉压与左心室肥厚的关系

目的探讨老年高血压患者脉压(PP)与左心室肥厚(LVH)的关系。方法老年高血压患者212例,按PP水平分为<40mmHg、40～60mmHg、60～80mmHg及>80mmHg4组,分别进行心脏超声检查,计算出左室质量指数(LVMI),分析PP与LVMI的关系。结果随着PP的增大,LVMI明显增加,各组间LVMI有显著性差异(P<0.05)。结论老年高血压患者PP增大可以促进LVH的发生及发展,PP是LVH重要的危险因素及预测因子。     

Histological findings after angioplasty using conventional balloon, radiofrequency thermal balloon, and stent for experimental aortic coarctation

Abstract Background : Use of balloon angioplasty or stent implantation has been reported to be effective in relieving coarctation of the aorta. However, restenosis frequently occurs after balloon angioplasty for native aortic coarctation in small infants, and sometimes develops after stent implantation because of vessel growth. The causes of restenosis remain uncertain. The purpose of this study was to assess the histologic differences in vascular responses to angioplasty using conventional balloon, radiofrequency thermal balloon (RFTB), or stent for experimental aortic coarctation. Methods : The authors surgically created an aortic coarctation model using 14 puppies. Angioplasty using conventional balloon, RFTB, or stent was performed 1 month after the initial operation. At the acute or chronic phase after angioplasty, the animals were killed and histologic studies were performed. Results : More vascular injuries were noted in the specimens from animals undergoing conventional angioplasty than in those with RFTB or stent. However, neointimal hyperplasia was seen more often after RFTB or stent because of the proliferation of smooth muscle cells from the tunica media, caused by secretion of growth factors. Apoptosis reached a peak 1?2 weeks after angioplasty, regardless of the type of intervention. Conclusions : The authors conclude that angioplasty with RFTB or stent can provide relatively small injuries in the vessel wall for aortic coarctation, but care must be taken to prevent restenosis caused by intimal hyperplasia, because neointima hyperplasia is more frequent after RFTB or stent.     

导管射频消融治疗严重症状性室性早搏的初步研究

目的:探索导管射频消融治疗严重症状性室性早搏(室早)伴或不伴室早诱发的短阵室性心动过速(室速)的安全性、效率和方法学。方法:18例严重症状性室早患者入选本研究,术前室早数量平均(117±37)次/h。术前根据同步12导联体表心电图初步推测室性早搏产生部位,术中依据初步推测的室早产生部位采用心室激动顺序标测法与起搏标测法进行室早标测定位,大头消融电极标测到室早最早激动点较体表心电图QRS波提前25ms以上或消融电极起搏心电图QRS波图形与室早图形11/12以上一致时放电消融。结果:18例患者导管射频消融即时成功16例,术后室早数(6±2)次/h,较术前显著减少(P<0.05);随访12个月,18例中16例消融成功,成功率88.9%;无严重并发症发生。结论:导管射频消融治疗严重症状性室早伴或不伴室早诱发的短阵室速安全、有效,同步12导联体表心电图对室早的定位有重要的指导意义。     

脉压与心脑血管疾病危险因素的关系探讨

目的：了解人群脉压的分布特征及其与心血管病危险因素的关系。方法：对某医院2003-2004年体检者的血压、心率、血脂、血糖、血尿酸等资料进行描述，分析脉压与心血管疾病危险因素的关系。结果：本组人群平均脉压42．99mmHg，男女差异无统计学意义（P〉0．05）；随脉压增加，多种危险因素如体重指数、血压（收缩压、舒张压）、血糖、血脂（胆固醇、甘油三脂、低密度脂蛋白胆固醇）、血尿酸等均呈增加趋势（P〈0．001），收缩压增加的趋势强于舒张压；在较高的脉压水平，各种代谢性疾病如高脂血症、高尿酸血症、糖尿病等的检出率均增高（P〈0．001）。结论：脉压增大与多种代谢性疾病之间存在密切关联；脉压升高是心脑血管病的重要危险因素，应予以高度重视。     

经导管射频消融术治疗快速性心律失常2 064例结果分析

目的 通过对射频消融（RFCA）治疗快速性心律失常的结果进行分析，以总结RFCA的治疗经验。方法 对我科开展RFCA治疗快速性心律失常11年的工作进行总结，对2064例患者的治疗结果进行回顾性分析。结果 2064例患者中2008例RFCA治疗成功，成功率达97．3％。并发症发生率为0．73％（15／2064），其中前5年为1．48％（9／609），后6年为0．41％（6／1455）；2例安置了永久性心脏起搏器。复发率为1．54％（31／2008），有28例再次行RFCA治疗获得成功。结论 （1）RFCA治疗快速性心律失常安全、有效、成功率高、并发症发生率低。（2）RFCA治疗快速性心律失常的成功率及并发症发生率与术者的操作技术及经验密切相关。     

半月神经节射频热凝治疗难治性三叉神经痛

目的探讨半月神经节射频热凝治疗难治性三叉神经痛效果和安全性。方法对三叉神经第Ⅱ支合并第Ⅰ、Ⅲ支或Ⅰ、Ⅱ、Ⅲ支并存疼痛者应用改良的前入路卵圆孔穿刺法行射频热凝毁损术。应用C型臂定位下行卵圆孔穿刺。射频温度控制在75-90℃。结果优良46例，良好1例，总有效率为100％。无严重并发症，随访42例3～18个月，无复发患者。结论在C型臂引导下射频热凝半月神经节毁损术治疗难治性三叉神经痛疗效可靠、定位准确，时患者更安全。