Three-dimensional assessment of urinary stone on non-contrast helical computed tomography as the predictor of stonestreet formation after extracorporeal shock wave lithotripsy for stones smaller than 20 mm

The incidence of stonestreet formation after extracorporeal shock wave lithotripsy (ESWL) rises with increasing stone burden. However, stonestreet after ESWL is often experienced even in stones smaller than 20 mm. To examine whether the non-contrast helical computed tomography (CT) data could predict stonestreet formation in these stones, 53 radiopaque stones of 5-20 mm treated with ESWL were evaluated. Maximal dimension was measured on plain radiograph. From an attenuation value histogram graphed from the CT data, total stone volume and mean attenuation value were calculated. Seven stonestreets longer than 25 mm developed. There was no significant difference in maximal dimension and total stone volume between stones that did and stones that did not develop stonestreet. Mean attenuation value was the sole significant predictive factor. Application of mean attenuation value with cut-off level of 650 HU would anticipate stonestreet formation with a sensitivity of 85.7% and a specificity of 71.7%. The estimated risk of stonestreet formation is high in the treatment of stones with higher mean attenuation value.     

老年人根管治疗疗效的相关因素

目的:研究老年人根管治疗疗效及其影响因素.方法:对56例65岁以上老年人,根管治疗后2年以上的126颗牙齿进行检查,按治疗后年限分3组:2～3年组,4～5年组,6年以上组.应用根尖周指数(Periodicalindex)评定X线片和综合临床检查,对其治疗进行评价.结果:老年人根管治疗成功率为72.2%;三组间根管治疗成功率差异无显著性.恰填根管治疗的成功率(82.2%)比欠填和超填的成功率(47.2%)要高;恰填病例中,冠方修复体质量好的患牙比质量差的患牙根尖周炎发病率低(25.7%和58.4%);去除欠填和超填病例后,桩冠修复患牙的根管治疗成功率为58.8%,而未做桩冠修复的患牙成功率为87.5%.结论:根充质量、冠方修复体质量、桩冠修复是影响老年人根管治疗疗效的主要因素.     

CT血管成像对肝细胞癌合并肝动脉-门静脉分流的诊断价值

目的探讨CT血管成像（CTA）对肝细胞癌（HCC）合并肝动脉-门静脉分流（APS）的诊断价值。方法127例HCC患者分别接受肝脏多层螺旋CT动态增强扫描和DSA检查，间隔时间3-15d。所有患者进行CTA检查，并以DSA为标准，对照分析CT动态增强扫描基础上进行CTA成像对APS的诊断价值。结果DSA证实52例（40．94％）HCC患者合并APS，中央型33例，周围型19例。CT横断面与横断面基础上结合CTA诊断APS的敏感度均为94．23％（49／52），特异度分别为84．00％（63／75）和97．33％（73／75），正确率分别为88．19％（112／127）和96．06％（122／127），阳性预测值分别为80．33％（49／61）和96．08％（49／51），阴性预测值分别为95．45％（63／66）和96．05％（73／76）。CTA排除了横断面CT对4例中央型APS和6例周围型APS的假阳性诊断。与DSA比较，多层螺旋CT对APS的分型符合率达88．46％（46／52），其中，中央型90．91％（30／33），周围型84．21％（16／19）。CTA还直观地显示23例重度分流中央型APS的供血动脉，其中19例为肝固有动脉分支，4例为胃十二指肠动脉分支。结论在多层螺旋CT动态增强扫描基础上进行CTA成像，能有效提高APS诊断的特异度和正确率。     

小脑幕切迹疝CT诊断及临床价值

目的:探讨小脑切迹疝的CT早期表现及临床应用价值。方法:对临床诊断为小脑切迹疝75例CT表现和临床分型进行分析。结果:小脑切迹疝CT表现鞍上池、脚间池、环池、四叠池缩小变形或闭塞分别占52/75、52/75、47/75、20/75。中脑变形移位33/75,脑室系统扩张(侧、三脑室)7/75,蛛网膜下腔出血占26/75。临床分前疝、后疝、全疝、环疝,各占24/75、31/75、16/75、4/75。行脑定位抽吸术治疗27例,外科手术34例。结论:小脑切迹疝CT表现具有特征性,脑疝早期可无典型脑疝临床表现,而CT检查可早期诊断,且优于其他检查。     

一种西门子新型X线机的综合性能与安装

本文叙述西门子型号为Polydoros 80/100的新型X线主机,该主机采用微电脑控制技术、光纤维传输技术及中频技术,X射线剂量精度高,影像质量优良,故障率低,是一种技术较为成熟的X线主机,也是当今西门子公司产品的主流机种。该机的安装调试具有一定难度,本文同时针对这一问题进行讨论,并总结归纳出一套安装调试全过程。     

冠心病的电子束CT诊断及评价

本文通过复习大量文献资料,阐述了电子束CT的原理及钙化评分方法,全面分析了电子束CT对冠心病的诊断价值、对冠心病预后的评价意义及对冠心病病情进展和治疗效果的监测意义等。总之,电子束CT可用于冠心病的诊断和评价。     

腹膜转移瘤的影像学诊断

目的探讨腹膜转移瘤的影像学表现特点。方法回顾性分析经手术及穿刺活检证实的35例腹膜转移瘤的影像学表现,并与手术结果对照,35例做CT平扫及增强扫描,5例行MR I检查。结果(1)腹膜转移瘤常表现为大量腹水(22/35);(2)腹膜结节状增厚(23/35);(3)大网膜饼形增厚(16/35)和大网膜污垢样改变(12/35);(4)肠系膜污垢样改变(12/35)及结节状改变(9/35);(5)腹腔单发或多发囊性改变,有占位效应(4/35)。结论CT/MR I是发现腹膜转移灶的重要影像学方法。     

Simultaneous Quantification of an Enantiomer and the Racemic Compound of Ibuprofen by X-ray Powder Diffractometry

Purpose. An X-ray powder diffractometric method was developed for the simultaneous quantification of the relative amounts of the racemic compound (±) of ibuprofen (I) and S(+)-ibuprofen (II), when they occur as a mixture. Methods. The X-ray powder diffraction patterns of I and II show pronounced differences. This formed the basis for the determination of the relative amounts of I and II when they occur as a mixture. X-ray lines with d-spacings of 14.41 and 4.37 Å were unique to I and II, respectively. Mixtures containing different proportions of I and II were prepared which also contained lithium fluoride (III) as an internal standard. Results. A linear relationship was obtained when the intensity ratio (intensity of the 4.37 Å line of II/intensity of the 2.01 Å line of III) was plotted as a function of the weight fraction of II in the mixture. Similar results were obtained in the case of I. Using these standard curves, the weight fractions of I and II in 'unknown' mixtures were determined. The experimentally determined analyte concentration ranged between 98 and 104% of the true value. The relative error in the analyses of individual samples was < 10%. The minimum detectable weight fraction of I in II and II in I were 0.032 (3.2% w/w) and 0.034 (3.4% w/w), respectively. The minimum quantifiable weight fractions were 0.136 for I and 0.112 for II. Since the X-ray diffraction patterns of S(+)-ibuprofen and R(–)-ibuprofen are identical, the conclusions drawn regarding mixtures of I and II will also hold true in the quantitative analyses of mixtures of I and R(–)-ibuprofen.     

胸部高分辨率CT检查技术的临床应用

笔者对５０例肺部疾病胸部常规ＣＴ和高分辨率ＣＴ（ＨＲＣＴ）图像进行了对照分析。其中特发性肺间质纤维化（ＩＦＰ）８例，肺转移癌５例，支气管扩张１５例，慢性阻塞性肺气肿１５例，周围型肺癌７例，结果表明：ＨＲＣＴ在ＩＦＰ、支气管扩张和肺气肿的显示明显优于常规ＣＴ（Ｐ＜０．００１），在对肺部原发或转移性肿瘤的显示能提供更多的诊断信息。笔者还讨论了ＨＲＣＴ的检查技术和图像后处理，分析了影响ＨＲＣＴ的若干因素，指出通过缩小视野（ＦＯＶ），减少象素做图像的重建放大显示肺部局部结构更为清楚方便，应灵活运用。     

原发性小肠恶性肿瘤的CT诊断

本文回顾性分析３４例经病理证实的原发性小肠恶性肿瘤的ＣＴ表现。病变包括腺癌１６例，平滑肌肉瘤１２例，淋巴瘤６例。ＣＴ扫描能明确肿瘤向腔内和腔外侵犯的程度，清晰显示肿瘤与邻近结构的关系，有无局部及远处转移等，为临床治疗提供帮助。鉴别诊断应包括小肠良性肿瘤、炎性病变和转移性肿瘤等。