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131.
三维超声技术及其在肝癌诊治中的应用 总被引:2,自引:0,他引:2
介绍三维超声成像技术的原理,讨论三维超声在肝癌的诊断性应用及在肝脏手术和介入中的治疗性应用。 相似文献
132.
聚焦超声治疗慢性宫颈炎500例临床分析 总被引:12,自引:0,他引:12
目的 探讨聚焦超声治疗宫颈炎的临床疗效.方法 收治慢性宫颈炎700例,分为聚焦超声治疗组(超生治疗组)500例,微波治疗对照组200例.观察其临床症状、体征及疗效.结果 超声治疗组中、重度宫颈炎的疗效明显高于微波对照组,差异有显著意义(P<0.05);两种方法治疗后,宫颈修复过程中阴道排液、出血等并发症的发生率,超声治疗组明显低于微波对照组,差异有显著意义(P<0.05).结论 聚焦超声治疗宫颈炎疗效确切,副作用及并发症少,是目前治疗宫颈炎的一种有效方法. 相似文献
133.
目的:探讨经腹超声及术中超声在胰腺结石诊断、治疗中的价值。材料和方法:对25例胰腺结石患者行经腹和术中超声检查。经腹超声主要观察胰管扩张程度,胰腺结石大小、位置,是否合并胆囊及胆道结石、胰腺假性囊肿等。术中超声观察是否有结石残留。结果:经腹超声显示25例患者主胰管扩张,胰腺实质增粗、增强。结石位于头部9例,位于全胰腺16例,伴有胆道梗阻征象13例,其中合并胆囊及胆道结石8例,并发胰腺假性囊肿3例,合并胰腺癌2例;术中超声形式显示6例未见残留结石,19例有残留结石,手术取出残留结石24枚。结论:经腹超声诊断主胰腺管结石敏感性较高,术中超声在判断残留结石及鉴别胰小管结石与胰腺实质钙化灶方面具有重要价值。 相似文献
134.
螺旋CT三维重建脊柱的临床意义和应用前景 总被引:1,自引:0,他引:1
目的:探讨螺旋CT扫描和三维重建在脊柱病变中的临床应用价值。方法:对12例脊柱疾病患者进行螺旋CT扫描和三维重建。结果:腰椎间盘突出症和椎管狭窄症3例,脊柱骨折5例,侧弯畸形2例,肿瘤2例,均得到正确诊治。结论:螺旋CT扫描及三维重建技术可广泛应用于脊柱病变的诊断,能直观显示脊柱病变部位的形态。 相似文献
135.
Background: The slitlamp can be used to estimate the anterior chamber depth (ACD). The length of a slit object is increased until the corneal and iris/lens images appear to just touch. Multiplying the just‐touching‐slit‐length (JTSL) by a conversion factor gives an estimate of the ACD as measured by ultrasonography. The purpose of this study was to determine if central corneal thickness (CCT) affects the accuracy of this technique. Methods: The ACD of 50 subjects was measured by A‐scan ultrasonography and estimated by the slitlamp technique. CCT was measured by ultrasonic pachometry. The refractive error was determined subjectively. Results: The average ultrasonographic ACD for all subjects was 3.32 ± 0.65 mm. The average JTSL was 2.46 ± 0.38 mm. The conversion ratio between the ultrasonographic ACD and the average JTSL was 1.35. The predicted ACD using the regression equation of JTSL on the ultrasound anterior chamber depth (USACD) was 3.32 ± 0.54 mm. The corresponding value using the regression equation of JTSL and CCT on USACD was exactly the same, that is, 3.32 ± 0.54 mm. Conclusion: Incorporation of CCT into a regression equation does not improve the accuracy of the Smith technique. 相似文献
136.
目的 探讨高强度聚焦超声(HIFU)所致的大鼠急性肝损伤后血清炎性因子水平的变化及乌司他丁(UTI)对其的保护效应.方法 建立高强度聚焦超声致大鼠急性肝损伤模型,Wistar大鼠24只随机均分为单纯高强度聚焦超声致伤组(H组)、乌司他丁处理组(U组)和空白对照组(D组).在致伤后1、3、6、12和24h分别检测三组血清中白细胞介素-2(IL-2)、白细胞介素-10(IL-10)和肿瘤坏死因子-α(TNF-α)三种炎性细胞因子的含量.结果 与D组比较,H组致伤3h后IL-2和TNF-α开始明显升高,并分别于致伤后6h和12h达到峰值.U组IL-2和TNF-α升高幅度明显低于H组(P<0.01),且于致伤后24h基本恢复正常,而IL-10水平显著高于H组.结论 高强度聚焦超声致大鼠急性肝损伤后大鼠机体发生显著炎症反应,乌司他丁能下调致炎因子水平,并可上调抑炎性因子水平,阻断炎症反应,显示出一定的保护效应,改善预后. 相似文献
137.
螺旋CT扫描与多模式三维重建诊断腰椎间盘突出症 总被引:4,自引:0,他引:4
目的 探讨螺旋CT扫描容积数据与三维重建诊断腰椎间盘突出症(LDH)的价值。资料与方法 94例行连续容积扫描:准直3~5mm,螺距1.5~3.0,以1.3~2.7mm间距后重建;源影像输入AW4.0工作站,应用多平面重建(MPR)、表面遮盖显示(SSD)和仿真内镜(VE)等软件显示病变,并与椎间盘镜(MED)诊治对照。结果 8例正常;LDH86例:中央型、侧旁、椎间管、椎管外、侧方及混合型分别为19、39、5、2、3、18例。三维重建显示LDH的立体结构为堤坡形、扁丘形、尖丘形、双(多)丘形及游离形分别为34、26、9、5、2例。VE诊断LDH的准确度、灵敏度、特异度分别为95%、100%、80%。VE能模拟MED效果。结论 容积数据与多模式三维重建能提供诊断LDH更全面的信息,并模拟微创手术治疗。 相似文献
138.
Margaret A. Paggiosi Aubrey Blumsohn Reinhard Barkmann Richard Eastell 《Journal of clinical densitometry》2005,8(4):436-444
It is unclear whether longitudinal change in phantom measurements bears any relation to the long-term in vivo instrument performance of quantitative ultrasound devices. Longitudinal quantitative ultrasound phantom data were obtained by measuring the manufacturer-provided phantom at ambient temperature and two different sets of Leeds phantoms at either ambient temperature or following a phantom temperature-control protocol. Measurements were performed using the Achilles Plus bone densitometer. Changes in longitudinal phantom data were compared to in vivo quantitative ultrasound data obtained from seven healthy, young volunteers. A cosinor model with linear trend and Hotelling's T2-test were used to quantify seasonal rhythms and long-term drift in quantitative ultrasound variables. Temperature effects and marked seasonal rhythms on quantitative ultrasound phantom measurements were evident but were far less apparent in vivo. Longitudinal precision of quantitative ultrasound variables was poorer for the manufacturer-provided phantom than for phantoms that were subjected to a temperature-control protocol or for healthy volunteers. This study has shown that longitudinal precision and longitudinal change differs between in vivo and phantom data. Longitudinal quantitative ultrasound measurements for monitoring change in skeletal status cannot, as yet, be properly controlled. 相似文献
139.
Kenji Yamao Atsushi Irisawa Hiroyuki Inoue Koji Matsuda Mitsuhiro Kida Shomei Ryozawa Yoshiki Hirooka Teruo Kozu 《Digestive endoscopy》2007,19(Z1):S180-S205
Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented. 相似文献
140.
A prototype electronic radial scan ultrasound endoscope has been developed by Olympus (Tokyo, Japan) for endoscopic ultrasound (EUS) study. The ultrasound view‐angle of this model is 360° vertical to the scope. Though the diameter of the scanner and the shaft of the scope is bigger than those of the present mechanical radial scan model, clinical manipulation of the new scope is the same as that of the present model. Image quality of the ultrasound picture demonstrated by the electronic radial model was as clear as those provided by the mechanical radial scan model. Ultrasound penetration was better and satisfactory because of less echoic reduction compared to the mechanical radial model. The newly developed electronic radial model can be evaluated as an ultrasound endoscope for the next generation. The advantage of this system is to facilitate the clinical use of color Doppler function and tissue harmonic imaging, and this system can be operated by the same monitor unit as a convex model of ultrasound endoscope. 相似文献