18F-FDG与18F-FLT PET/CT延迟显像对肺结节诊断效能的评价

目的 通过对多中心、前瞻性研究中接受了18F-脱氧葡萄糖(FDG)与18F-脱氧胸腺嘧啶核苷(FLT)延迟显像病例的分析,探讨18F-FDG与18F-FLT延迟显像对肺结节诊断的效能.方法 6个PET/CT中心,从2006年1月至2007年6月,按照统一标准,采用同机型、同一扫描条件,开展了肺结节样病变18F-FLT和18F-FDG PET/CT显像的多中心临床研究.在经确诊的55例病例中,25例患者进行了18F-FLT显像和延迟显像,34例患者进行了18F-FDG延迟显像.按常规计算延迟显像时病灶最大标准摄取值(SUVmax)及与早期显像时SUVmax相比的变化率(△SUVmax).对照临床确诊结果分析其诊断效能.采用SPSS11.0软件进行统计学处理.结果 18F-FDG延迟显像患者中,6例肺癌中5例、12例结核中9例、16例炎症或其他良性结节中9例的SUVmax较早期相升高.18F-FLT延迟显像组中,7例肺癌中3例、8例结核中3例和10例其他良性病灶中2例的SUVmax上升.经分组统计分析,不同疾病组间18F-FDG延迟显像SUVmax和△SUVmax差异无统计学意义;18F-FLT延迟显像SUVmax和△SUVmax组间差异也无统计学意义.无论18F-FDG还是18F-FLT,延迟显像的诊断效能均不如早期相.无论早期还是延迟显像,单独18F-FDG或18F-FLT显像的诊断效能均不如二者联合应用.结论 18F-FDG和18F-FLT延迟显像的SUVmax变化规律性不强,不宜单独应用于肺结节的鉴别诊断.     

多排螺旋CT在乳腺癌术前评估中的应用

多排螺旋CT的出现为乳腺癌诊断评估提供了一个全新的工具。本文旨在介绍乳腺多排螺旋CT高分辨率薄层增强扫描和相应之图像重建技术路线,及其在乳腺癌术前诊断评估中的作用与意义。     

螺旋CT三期扫描对肝纤维化诊断价值研究

目的探讨螺旋CT三期扫描对肝纤维化的诊断价值。方法对66例经肝穿刺活检病理证实的慢性乙型肝炎肝纤维化患者组和42例正常对照组进行螺旋CT三期增强扫描。根据纤维化程度分期进行影像资料和相关指标的统计分析。结果肝左叶增大,肝表面形态及肝实质密度的改变,脾脏增大,门静脉增宽和侧枝循环的建立等影像学改变,随着肝纤维化严重程度的加重而有统计学差异。本研究显示57例肝纤维化患者螺旋CT三期扫描诊断肝纤维化52例,敏感性91.2%,特异性77.8%。各期肝纤维化分期准确28例,准确率49.1%;准确判断轻度纤维化(S1、S2)或重度纤维化(S3、S4)44例,准确率77.2%,诊断早期肝硬化16例,准确率84.2%。结论螺旋CT三期扫描能判断肝纤维化的程度,而且是动态观察肝纤维化的病程演进和临床随访的有效手段。     

64排螺旋CT冠状动脉造影与DSA的对照研究

目的:通过和冠脉造影对比,评价64排螺旋CT冠状动脉成像在冠状动脉狭窄中的临床应用价值。方法:28例患者同时行64排螺旋CT冠状动脉成像和有创性冠脉造影检查,依据AHA17段分段法,评价所有有效节段,并将两者进行对比。结果:冠脉造影显示阴性病例占7.1%(2例),单只病变占21.4%(6例),多支病变占71.4%(20例)。按节段分析,CT检出冠脉狭窄的敏感度,特异度,阳性预测值和阴性预测值分别为91.1%,94.6%,90.0和95.3%。结论:64排螺旋CT冠状动脉成像和传统的冠脉造影检查对检出正常冠脉节段以及狭窄节段具有很好的一致性。     

547例垂体腺瘤延迟诊断原因及影像诊断分析

目的:提高垂体腺瘤特别是微腺瘤早期影像诊断率。方法:通过对所搜集病史资料完整,经医学影像学确诊和手术病理证实的547例垂体腺瘤(内有251例微腺瘤)延迟诊断原因的分析,找到影响垂体腺瘤早期诊断的因素。结果:296例垂体大腺瘤蝶鞍X线平片、CT、MR常规检查即可诊断。CT骨窗蝶鞍片有助于垂体微腺瘤的诊断,251例微腺瘤经高分辨力CT薄层冠状强化扫描和高场强MR薄层强化扫描得以明确诊断。结论:熟悉垂体腺瘤的首发症状,及时行CT、MR常规扫描可明确大腺瘤的诊断,CT骨窗片可发现垂体微腺瘤的佐证。高场强MR薄层强化扫描是目前诊断垂体微腺瘤的最佳方法,高分辨力CT冠状薄层强化扫描次之,结合神经内分泌学检查是提高垂体腺瘤影像学早期诊断率的主要措施。     

CT appearances of hydatid disease at various locations

Hydatid disease has characteristic imaging features on CT, which allow accurate preoperative diagnosis in most cases. However, when it occurs at unusual locations the diagnosis is often difficult, especially as the imaging appearance varies at different sites. In this article we have presented a pictorial review of the CT features of disease due to Echinococcus granulosus at various sites in the human body.     

Multi-detector CT angiography for lower gastrointestinal bleeding: Can it select patients for endovascular intervention?

This is a retrospective review of the results at our institution of using multi-detector CT angiography (CTA) to localise lower gastrointestinal (GI) bleeding. We hypothesised that in our patient population: (i) CTA was unlikely to demonstrate bleeding in patients who were haemodynamically stable; (ii) in haemodynamically unstable patients in whom CTA was undertaken, the results could be used to select patients who would benefit from catheter angiography; and (iii) in haemodynamically unstable patients in whom CTA was undertaken, a subgroup of patients could be identified who would benefit from primary surgical treatment, avoiding invasive angiography completely. A retrospective review was conducted of the clinical records of all patients undergoing CTA for lower GI haemorrhage at our institution between 1 January 2005 and 30 June 2007. Out of the 20 patients examined, 10 had positive CTAs demonstrating the bleeding site. Nine were haemodynamically unstable at the time of the study. Four patients with positive CT angiograms were able to be treated directly with surgery and avoided invasive angiography. Ten patients had negative CTAs. Four of these were haemodynamically unstable, six haemodynamically stable. Only one required intervention to secure haemostasis, the rest stopped spontaneously. No haemodynamically stable patient who had a negative CTA required intervention. CTA is a useful non-invasive technique for localising the site of lower GI bleeding. In our patient population, in the absence of haemodynamic instability, the diagnostic yield of CTA was low and bleeding was likely to stop spontaneously. In haemodynamically unstable patients, a positive CTA allowed patients to be triaged to surgery or angiography, whereas there was a strong association between a negative CTA and spontaneous cessation of bleeding.     

64层螺旋CT血管成像技术对主动脉夹层动脉瘤的诊断价值

目的:评价64层螺旋CT对主动脉夹层的价值及优势。方法:本组增强扫描对比剂为Omnipaque,浓度为350mgI/ml,剂量为100ml。注射速率为4ml/s,扫描延迟时间为25~30s。将扫描原始数据重建成0.625mm的横断面图像,然后传送至AW4.2高级图像处理工作站,分别进行VR、MPR、MIP重建。结果:①11例患者的血管成像扫描时间为7~10s;②De BackeyⅠ型主动脉夹层3例,De BackeyⅢ型8例;③11例患者在VR、MPR重建图像上均清晰显示出升主动脉、主动脉弓、降主动脉、腹主动脉、双侧髂总动脉、双侧髂内外动脉以及腹腔动脉干、肠系膜上动脉、双侧肾动脉主要分支的血管,图像清晰,血管对比明显,血管边缘无阶梯状改变;④11例患者均能清晰显示主动脉夹层的开口、范围及内膜瓣的情况;⑤3例肠系膜上动脉有不同程度的狭窄;2例患者肠系膜上动脉有夹层表现;5例患者一侧肾动脉有不同程度的狭窄,其中1例伴明显肾血供障碍;⑥11例患者均可以清晰显示真、假腔,4例患者假腔内有不同程度的血栓形成;⑦1例主动脉夹层患者经内支架置入术后,支架膨胀良好,其位置大小形态良好,原内膜破口被封闭,无渗漏现象,假腔内完全血栓形成。结论:64层螺旋CT血管成像技术可以在无创或微创的情况下清晰地显示主动脉夹层及主要分支血管的改变,为临床的诊断和治疗提供有价值的依据。     

CT的分叶征表现在肺内孤立结节影像诊断中的价值

目的探讨CT的分叶征表现在肺内孤立结节影像诊断的价值以及CT多平面重组（MPR）对此征检出的意义。方法观察病理证实的周围型小肺癌137例及良性肺内结节45例，将结节的边缘分为4型。对28例肺癌、22例良性结节行MPR，考察其显示分叶征的作用。引入可能性比值（likelihood ratios，LR）以量化良恶性病变在形态学上存在重叠的表现。结果Ⅰ型边缘结节对良性病变的特异性为83．3％（20／24），敏感性为44．4％（20／45）。Ⅳ型边缘结节对周围型小肺癌的特异性为97．6％（83／85），敏感性为60．7％（83／137）。表明Ⅰ型边缘是良性病变的特点；而Ⅳ型边缘是恶性病变的特征。Ⅳ型边缘的结节恶性病变在MPR重组图像上的检出率为64．3％（18／28），与横断面扫描差异有统计学意义（P〈0．01）。结论分叶征对肺内孤立结节的诊断有价值，MPR配合横断面薄层图像有助于提高该征的检出率。