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61.
BACKGROUND: High-intensity focused ultrasound (HIFU) is a minimally invasive technique used in achieve coagulation necrosis. We evaluated biochemical disease-free survival rates, predictors of clinical outcome and morbidity in patients with localized prostate cancer treated with HIFU. METHODS: A total of 181 consecutive patients underwent HIFU with the use of Sonablate (Focus Surgery, Indianapolis, IN, USA). Biochemical recurrence was defined according to the criteria recommended by the American Society for Therapeutic Radiology and Oncology Consensus Panel. The median age and pretreatment prostate-specific antigen (PSA) level were 70 years (range 44-88) and 9.76 ng/mL (range 3.39-89.60). A total of 95 patients (52%) were treated with neoadjuvant hormones. The median follow-up period for all patients was 18.0 months (range 4-68). RESULTS: The biochemical disease-free survival rates at 1, 3 and 5 years in all patients were 84%, 80% and 78%, respectively. The biochemical disease-free survival rates at 3 years for patients with pretreatment PSA less than 10 ng/mL, 10.01-20.0 ng/mL and more than 20.0 ng/mL were 94%, 75% and 35%, respectively (P<0.0001). Multivariate analysis identified pretreatment PSA (P<0.0001) as a independent predictor of relapse. CONCLUSION: High-intensity focused ultrasound therapy appears to be a safe and efficacious minimally invasive therapy for patients with localized prostate cancer, especially those with a pretreatment PSA level less than 20 ng/mL.  相似文献   
62.
Transcranial Doppler (TCD) is an accepted modality for the evaluation of cerebral blood flow velocities. OBJECTIVES: The purpose of this study was to test the feasibility of bedside TCD measurement in the emergency department (ED) with critically ill, intubated patients. METHODS: A prospective convenience sample of patients presenting to a university hospital over a two-month period underwent TCD evaluation of the middle cerebral artery. Intubated patients with head trauma and any patient requiring tracheal intubation were eligible. A 2-MHz Doppler probe was positioned over the temporal bone to acquire blood flow velocities. An emergency medicine resident and research assistant obtained measurements. Continuous TCD tracings were recorded on a video cassette recorder tape for quality assurance review and data collection. Vital signs and therapeutic interventions were also recorded. Flow velocities were measured in cm/s; the peak Resistance Index (RI) was calculated for each patient. RESULTS: A total of 30 patients were enrolled in the study. Adequate tracings were obtained in 25 patients (83%) without a disruption of resuscitation. Tracings could not be obtained in five patients; they were listed as TCD failures. However, in two of these patients, adequate flow velocity tracings were obtained after resuscitation. Four patients were evaluated during tracheal intubation. One patient was monitored successfully during cardiopulmonary resuscitation. The median time required for data acquisition was 1.9 minutes. The mean highest RI for those who expired was 0.84. For those who survived, the mean highest RI was 0.52. The difference of 0.32 was statistically significant (p = 0.04). CONCLUSIONS: Noninvasive blood flow velocity monitoring of the middle cerebral artery using TCD is feasible in the ED when performed at the bedside on intubated patients with traumatic brain injury and others during tracheal intubation and resuscitation.  相似文献   
63.
The clinical and ultrasonographic (US) features of 15 cases of mesenteric or omental cyst are herein described. This series included seven male and eight female patients, whose age ranged from 2–89 years. Correct clinical diagnosis was made in two children only, but preoperative US examination accurately demonstrated the lesion in 11 of 13 patients (85%). These cystic lesions usually had a thin wall, internal septations, and fluid content with sedimentation. Enteric duplication cysts had a relatively thick wall merging with the muscle layer of bowel loop, and multiloculation was noted mainly with cystic lymphangiomas or pseudocysts. The diagnostic and surgical management of these lesions are briefly reviewed and their US appearance is illustrated.  相似文献   
64.
三维超声对胎儿体表畸形的诊断价值   总被引:2,自引:0,他引:2  
目的:探讨三维超声成像在胎儿体表畸形诊断的临床价值。方法:利用三维超声仪对在我院进行产前检查的妊娠20~41周的3241例孕妇、共3277个胎儿进行二维及三维超声检查,统计并比较超声诊断与随访结果。结果:140例各种发育异常胎儿,其中体表畸形胎儿34例,二维超声诊断正确者21例,9例体表畸形胎儿二维超声检查不能作出明确诊断;三维超声进一步检查诊断正确者共30例;二维及三维超声检查误诊1例胎儿足内翻,生后证实正常,漏诊1例耳廓缺失、2例多指畸形,生后随访证实。三维超声对胎儿体表畸形检出的敏感性、特异性及准确性分别为90.91%、99.97%、99.88%;二维超声对胎儿体表畸形检出的敏感性、特异性及准确性分别为63.64%、99.97%、99.60%。结论:三维超声能直观显示胎儿体表结构,三维超声检查诊断胎儿体表畸形的敏感性、特异性及准确性高,是二维超声检查的重要补充,与二维超声联合应用,可提高胎儿体表畸形的检出率。  相似文献   
65.
腮腺良性和恶性多形性腺瘤的超声研究   总被引:1,自引:0,他引:1  
目的研究腮腺良性和恶性多形性腺瘤的超声特点,为临床医师诊治提供有效依据。方法选取腮腺良性多形性腺瘤患者79例和恶性多形性腺瘤患者15例,对其肿块的大小、硬度、内部回声、彩色多普勒血流显像(CDFI)特点结合病理学诊断进行对照研究。结果恶性多形性腺瘤的声像图特点与良性多形性腺瘤相似,但其肿瘤相对较大,质地更硬,内部回声分布更紊乱。不同性质的肿瘤的大小和质地有显著性差异,(P<0.01)。结论多形性腺瘤的超声诊断主要依据二维图像之特点。当多形性腺瘤大于3.0 cm,硬度较硬,内部回声分布不均多提示恶性。  相似文献   
66.
目的观察氟伐他汀对老年肾动脉粥样硬化所致肾动脉狭窄(ARAS)的治疗作用及其抗炎机制。方法将在我院门诊及住院的54例老年ARAS患者,随机分为治疗组及对照组,对照组给予常规降压治疗,治疗组每晚加服氟伐他汀40 mg。比较两组治疗前及治疗后尿蛋白排泄率(UAER)、血肌酐(Scr)、C反应蛋白(CRP)及肾脏血管多普勒超声中肾动脉收缩期峰值速度(PSV)、肾动脉血流加速度时间(AT),肾动脉峰值流速与肾动脉开口处腹主动脉流速之比(RAR)等指标。结果观察期间,两组上述指标均呈下降趋势,治疗组UAER,PSV,AT,RAR下降较对照组明显(P<0.05,P<0.01),治疗组CRP下降明显(P<0.05,P<0.01),对照组CRP变化不明显(P>0.05)。而且在两组血脂正常的老年ARAS所致肾动脉狭窄的患者进行比较分析也得出类似结果。结论氟伐他汀因降低CRP的致炎效应而改善肾动脉狭窄,且不依赖氟伐他汀的降血脂作用。  相似文献   
67.
Survival after resection of colorectal liver metastases has traditionally been associated with clinicopathologic factors. We sought to investigate whether echogenicity of colorectal liver metastasis as assessed by intraoperative ultrasound (IOUS) was a prognostic factor after hepatic resection. Prospective data on tumor IOUS appearance were collected in 84 patients who underwent hepatic resection for colorectal liver metastasis. Images were digitally recorded, blindly reviewed, and scored for echogenicity (hypo-, iso-, or hyperechoic). The median tumor number was 1 and the median tumor size was 5.0 cm. At the time of surgery, the IOUS appearance of the colorectal liver metastases were hypoechoic in 35 (41.7%) patients, isoechoic in 37 (44.0%) patients, and hyperechoic in 12 (14.3%) patients. Traditional clinicopathologic prognostic factors were similarly distributed among the three echogenicity groups (all p > 0.05). Patients with a hypoechoic lesion had a significantly shorter median survival (30.2 months) compared with patients who had either an isoechoic (53.2 months) or hyperechoic (42.3 months) lesion (p = 0.005). The 5-year survival after hepatic resection of colorectal liver metastasis was also associated with the echogenic appearance of the lesion (hypoechoic 14.4 vs isoechoic 37.4 vs hyperechoic 46.2%) (p < 0.05). Intraoperative ultrasound echogenicity should be considered a prognostic factor after hepatic resection of metastatic colorectal cancer. This study was presented at the 47th annual meeting of The Society for Surgery of the Alimentary Tract, Los Angeles, CA, USA, 22 May 2006.  相似文献   
68.
血管内超声显像在冠心病支架植入术中的应用   总被引:5,自引:1,他引:4  
目的探讨血管内超声在冠心病支架植入中的作用。方法50例患者的52处病变在支架植入前后分别用血管内超声进行定量和定性分析,并根据血管内超声标准决定支架的直径以及植入的终点,分析CAG和IVUS对支架植入终点判断的差异和最终获得的管腔面积大小的差别以及支架后管腔面积增大的机制。结果IVUS比CAG判断的平均支架直径大[(3.48±0.29)mmvs(3.36±0.33)mm,P=0.011],支架囊的最终峰值压力明显增大[(17.7±2.9)atmvs(12.8±2.4)atm,P<0.001],QCA测得的支架面积狭窄百分比减小(13.2%±6.6%vs16.6%±9.1%,P=0.044);首次高压扩张后支架满意率CAG达96.2%,而IVUS只有37.7%。IVUS指导后最终的球囊压力更高[(16.13±1.87)atmvs(12.62±2.61)atm,P<0.001],获得的管腔直径更大[(3.64±0.53)mmvs(3.31±0.57)mm,P<0.001],管腔面积也更大[(9.90±2.05)mm2vs(8.84±1.67)mm2,P<0.001],面积狭窄百分比更小(49.15%±9.03%vs54.24%±10.05%,P<0.001];所有患者支架的近段和远段CAG均未发现明显的狭窄。而IVUS却发现支架近段血管有39例(75.0%),远段血管有23(44.2%)例存在动脉粥样硬化斑块;支架植入后非脂质斑块较脂质斑块获得的管腔面积更大[(4.50±1.67)mm2vs(3.68±0.97)mm2,P<0.001],其中脂质斑块血管面积增大较非脂质斑块小1.30mm2,斑块压缩程度却增加0.48mm2。结论IVUS较CAG能更好地判断病变的性质,指导支架更好地选择,可获得更大的管腔面积,更小的面积狭窄百分比。  相似文献   
69.
糖尿病肾内动脉血流动力学改变的研究   总被引:1,自引:0,他引:1  
目的:观察糖尿病肾病不同时期肾内分级动脉血流动力学的改变。方法:用脉冲多普勒方法分别测量正常对照组、糖尿病正常蛋白尿阶段,隐匿性肾病.临床糖尿病肾病肾功能代偿期及糖尿病肾病肾功失代偿期各组肾内分级动脉Vmax、Vmin、TAMX、PI、RI血流参数.并与对照组比较。结果:糖尿病不同时期Vmax均增高.与正常对照组有显著性差异;Vmin随着病程的发展.逐渐减低;PI、RI随病情的进展逐渐增高.尤以糖尿病肾病肾功能代偿期及肾病肾功失代偿期明显。结论:多普勒超声是一种简便、直观、快速非创伤性检查糖尿病血流动力学改变的方法.通过对肾内分级动脉血流参数的观察.尤其是PI、RI的变化,判断糖尿病肾损害的程度。  相似文献   
70.
目的 :探讨二维彩色多普勒超声及彩色血管三维超声在颈动脉疾病的诊断价值。材料方法 :疑为缺血性脑卒中患者 80例 ,行颈动脉彩色多普勒超声检查 ,其中 2 8例同时做彩色血管三维超声成像 ,5 5例经临床、CT、MRI证实为脑梗死。结果 :①本组 5 5例脑梗死 ,彩色多普勒超声发现 4 9例颈动脉粥样硬化斑。②有脑梗死的彩色血管三维血流图呈“串珠”状 ,而非脑梗死的彩色血管三维血流图呈连续“圆锥”状。结论 :彩色多普勒超声诊断颈动脉粥样硬化有良好的价值 ,三维彩超是二维彩色多普勒超声的有益补充。  相似文献   
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