64层VCT首过期灌注成像对肺部结节的诊断价值

目的:探讨首过期的64层VCT肺灌注成像对肺部结节的诊断意义。方法:对108例肺结节患者进行CT灌注扫描,测定肺结节的时间-密度曲线(TDC)、血容积(BV)、血流量(BF)、平均通过时间(MTT)和表面通透性(PS)的数值,并测量肺结节增强前的CT值、增强值和结节-动脉增强值之比(S/A)。标定结节的血管内皮生长因子(VEGF),评价肺结节CT灌注和增强指数与VEGF表达的相关性。结果:肺癌的灌注指数高于肺良性结节。良、恶性结节的TDC形态不同。结论:CT肺灌注成像可定量的评价肺结节的血流灌注特点,对肺部结节有较大的诊断及鉴别诊断意义。     

颅内肿瘤动态CT检查初探

74 patients with various intracranial tumors were studied by means of dynamic CT, among them 45 cases were confirmed by operation and pathology. In analyzing the time-density curve and the ratio of increase in CT number of the tumoral tissue to that in the arterial lumens (tissue-blood ratio, TBR), we found that: (1) Dynamic CT technique is safe and easy to perform suitable for out-patients; (2) The time-density curves in acoustic neurinoma, meningioma, glioma and metastatic tumors are different from each other because of difference in vascularity and the degree of B.B.B. breakdown. Meningioma curve shows a rapid rise to the peak followed by a subsequent plateau; (3) TBR at the peak time (TBRp) is useful as an index for tumor. Combined analysis of time-density curve and TBRp is helpful for tumor differentiation.     

预注射双点监测法行肺动静脉CT血管成像的可行性研究

目的:评价预注射双点监测法行多层螺旋CT肺动脉成像(CTPA)和肺静脉成像(CTPV)的成像技术及图片质量。方法:应用MSCT对30例疑似肺动脉栓塞患者行CTPA及CTPV检查。对比剂剂量为20ml(370mg I/ml),所有患者均采用预实验时间-密度曲线法,监测平面定于支气管隆突水平。CTPA及CTPV的兴趣区(ROI)分别选在肺动脉主干及相应层面肺静脉内,分别获得肺动脉及肺静脉时间-密度曲线,以对比剂注射开始到增强峰值的时间为延迟时间。采用盲法对CTPA及CTPV图像中同级别肺动静脉CT值进行测量并进行统计学分析。结果:30例患者均同时获得肺动脉及肺静脉的时间-密度曲线。肺动脉对比剂达峰值时间为(10.2±1.8)s,肺静脉对比剂达峰值时间为(14.7±2.3)s。所有图像均能清晰显示肺动静脉1～4级血管。CTPA及CTPV图像中1～4级动静脉血管CT值差异均具有统计学意义(P<0.05)。结论:预注射双点监测法可同时完成CTPA及CTPV肺动静脉各级分支成像,并且达到临床诊断要求。     

时间—密度曲线在常见脑肿瘤鉴别诊断中的应用价值

目的：探讨时间-密度曲线在常见脑肿瘤CT动态增强扫描后鉴别诊断中的应用价值。材料与方法：对46例脑瘤患者进行固定层面、时间、速度、剂量增强扫描,然后用CT功能软件——时间-密度曲线进行后处理并分析。结果：15例脑膜瘤平均峰值109HU,增强高度59.8HU,峰时97s,曲线以速升-亚速降-缓降型为主（60%）;19例胶质瘤平均峰值70.1HU,增强高度25.4HU,峰时223s,曲线以亚速升-缓升型为主（52.6%);转移瘤平均峰值74.5HU,增强高度33.5HU,峰时95.8s,曲线以速升-缓降型为主（67%）。结论：平均峰值与增强高度脑膜瘤与胶质瘤、转移瘤差别非常显著（P＜0.01),到达峰值时间,胶质瘤与脑膜瘤、转移瘤差别非常显著（P＜0.01)。各种肿瘤的时间-密度曲线表现不一,对肿瘤的鉴别诊断有很大价值。     

颌面颈部肿瘤的CT灌注成像

CT灌注成像用于颌面颈部肿瘤的评价尚少见.本文通过对51例(53侧)腮腺肿瘤的CT灌注检查探讨了颌面颈部肿瘤的CT灌注成像的技术和应用价值,并提出在该检查过程中应注意:①谨慎选择合理的肿瘤输入动脉作采样;②不同的肿瘤采样方法会导致不同的CT灌注结果,应当合理使用.笔者认为CT灌注检查对鉴别颌面颈部良性肿瘤和恶性肿瘤、区分肿瘤组织与其周围正常组织均具有一定的辅助诊断价值.     

多层螺旋CT灌注成像在肺结节鉴别诊断中的应用

目的 探讨多层螺旋CT灌注成像在肺结节的良恶性鉴别诊断中的价值.方法 采用多层螺旋CT机对96例肺结节患者行灌注扫描,其中良性结节18例、炎性结节28例、恶性结节50例.以perfusion 3软件测定结节的血流量(BF),血容量(BV),平均通过时间(MTT),渗透表面积乘积(PS)以及拟合时间-密度曲线(TDC),采用灌注参数及曲线形态来评价结节的良恶性.结果 BF、BV在炎性结节与良性结节之间具有显著性差异(P＜0.05),炎性结节均大于良性结节.MTT在三组结节之间没有显著性差异(P＞0.05),PS在恶性结节与良性结节之间、以及良性与炎性结节之间具有显著性差异(P＜0.05),恶性结节与炎性结节均高于良性结节,三组不同性质结节之间的TDC曲线形态也不同.结论 CT灌注成像能够较准确的判断肺结节的性质,在良恶性鉴别诊断中具有重要意义.     

门脉峰值时间确定及其在螺旋CT门脉成像中的应用

目的探讨一次屏气试验剂量团注单层动态扫描是否能很好确定门脉造影剂峰值及其在SCIP成像中的应用价值。材料与方法一次屏气试验剂量团注单层动态扫描41例,观察CT图像的层面波动及门脉峰值时间,然后以峰值时间作为扫描延迟时间进行SCIP检查。结果一次屏气试验剂量团注单层动态扫描的CT图像几乎无层面上下波动,门脉时间-密度曲线无明显波动,门脉峰值时间平均为50.5s。41例SLTP均能显示门脉4级以上分支。结论一次屏气试验剂量团注单层动态扫描是一种简单实用的确定门脉造影剂峰值的方法。以门脉峰值时间作为扫描延迟时间可获得良好的SCTP图像。     

电子束CT颅内肿瘤动态扫描的价值初探

目的：探讨电子束ＣＴ的动态扫描及时间──密度动态灌注曲线对颅脑肿瘤的诊断和鉴别诊断价值。材料和方法：收集２１例颅内肿瘤均经电子束ＣＴ检查与手术病理证实。机器采用美国ＩｍａｒｔｏｎＣ－１５０型全身电子束成像系统。先平扫选择肿瘤最大中心层面作为扫描线，注射Ｏｍｎｉｐａｑｕｅ６０ｍｌ后采用３ｍｍ层厚单层动态扫描序列，在９０秒内完成扫描。结果：我们根据曲线形态将不同肿瘤组织曲线分为五种类型。动脉瘤曲线为Ａ型；正常脑组织为Ｂ型；脑膜瘤为Ｃ型；转移性肿瘤和三叉神经鞘瘤为Ｄ型；胶质瘤为Ｅ型。动态灌注曲线的类型和参数值与肿瘤内部血管分布和血脑屏障状况有关。结论：电子束ＣＴ的动态ＣＴ扫描在显示肿瘤内部血供和血脑屏障破坏情况方面价值很大，它有助于肿瘤良恶性的诊断和鉴别诊断。     

64层螺旋CT肺动脉成像的临床研究

目的：探讨64层螺旋凹肺动脉成像最佳扫描方法。方法：22例患者采用自动激发扫描、22例采用常规12s扫描、23例通过绘制时间密度曲线找出最佳扫描时间三种扫描方式。扫描完毕对数据进行后处理,包括MPR、MIP、VR。比较这三种扫描方法肺动脉的显影情况。结果：22例自动激发扫描患者中12例肺动脉显影清晰而肺静脉不显影,肺动脉显影清晰但肺静脉有强化8例,扫描失败2例;22例固定12s进行扫描,14例肺动脉显影清晰且肺静脉不显影,肺动脉显影清晰但肺静脉有强化者5例,扫描失败3例;23例采用时间密度曲线法进行扫描,21例肺动脉显影清晰且肺静脉不强化,肺动脉显影清晰但肺静脉有强化者2例,无扫描失败。结论：通过绘制时间密度曲线确定肺动脉扫描延迟时间的方法是64层螺旋CT肺动脉成像最佳扫描方法。     

多层螺旋CT及CTA诊断小肠间质瘤的价值

目的：探讨多层螺旋CT及其血管造影三维重建(3D-CTA)对小肠间质瘤的诊断价值。材料和方法：回顾性分析经手术、病理证实的11例小肠间质瘤的多层螺旋CT平扫和双期增强扫描及3D-CTA表现。结果：11例中,恶性8例、交界性2例和良性1例；肿瘤起源于空肠3例、回肠7例和十二指肠1例。CT平扫示良性间质瘤密度较均匀,恶性者密度不均,增强扫描动脉期示肿瘤均呈明显增强,良性者较均匀,恶性者不均匀,静脉期示肿瘤仍有明显增强；3D-CTA可清晰显示肿瘤供血血管。结论：小肠间质瘤的多层螺旋CT表现有一定的特征性,3D-CTA能清晰显示肿瘤供血血管,并有利于肿瘤定位。     

Differentiation of benign and malignant parotid tumors using deconvolution-based perfusion CT imaging: feasibility of the method and initial results

AIM: We evaluated the feasibility of perfusion CT (CTP) of the parotid gland and attempted to differentiate benign from malignant tumors. MATERIALS AND METHODS: CTP was performed in 17 patients with benign tumors and 10 patients with malignant parotid tumors. Data were postprocessed by using deconvolution-based perfusion analysis. Postprocessing-generated maps showed blood flow (BF), blood volume (BV), mean transit time (MTT), and capillary permeability surface product (PS). Regions of interest were placed through the tumor site and the contralateral healthy parotid tissue. Ratios of the perfusion values between the tumors and the contralateral healthy structures were also calculated. Pearson correlation coefficients were determined to compare the agreement between the two readers. RESULTS: Perfusion maps of all tumors were successfully obtained. High Pearson correlation coefficients comparing the two readers' visually measured abnormalities were observed (r=0.79-0.86, P=0.001) for all perfusion maps, The MTT and PS values between malignant and benign tumors were not significantly different. The BF and BV values were statistically significant different between the benign and malignant tumors (0.00相似文献   

肾透明细胞癌CT灌注成像特点的研究

目的:探讨肾透明细胞癌灌注成像的特点及临床应用价值。方法:37例经过手术病理证实的肾透明细胞癌患者(肿瘤生长部位均靠近肾门附近),术前均选择近肾门层面进行动态增强扫描,经过灌注软件处理分析分别获得肾癌组织及双侧肾皮质的血流量(BF)、血容量(BV)、平均通过时间(MTT)、组织通透性(PS)及时间密度曲线(TDC图)。结果:肾透明细胞癌肿瘤最高密度点血供丰富,但血流量较对侧正常皮质仍较低;肿瘤平均灌注较两侧皮质均低;肿瘤同侧肾脏皮质灌注较对侧低;肿瘤内不同密度点灌注特性不同;不同分级的肿瘤对静脉血流有不同的影响。结论:肾透明细胞癌CT灌注成像具有一定的特点,对其诊断及肾血流的评估具有一定的价值。     

多层螺旋CT灌注成像对慢性阻塞性肺疾病的诊断价值

目的 研究CT灌注成像对慢性阻塞性肺疾病(COPD)的诊断价值.方法 20例COPD患者和20例志愿者行8层螺旋CT灌注成像,采用电影扫描(cine)方式,层厚5 mm,扫描时间0.5 s/层,注射对比剂后延时5 s,总扫描时间为45 s,测量感兴趣区血流量、血容量、平均通过时间及表面通透性和时间-密度曲线.结果 COPD患者的时间-密度曲线较志愿者曲线平坦,峰值明显降低.COPD患者血流量[(24.77±11.49)ml·min-1·100 g-1]、血容量[(2.48±1.02)ml/100 g]及表面通透性[(2.75±1.13)ml·min-1·100 g-1]明显低于志愿者[血流量(290.14±107.59)ml·min-1·100 g-1、血容量(16.51±5.98)ml/100 g、表面通透性(8.80±3.03)ml·min-1·100 g-1];平均通过时间[(10.58±4.85)s]高于志愿者[(4.50±1.71)s],差异均具有统计学意义(P<0.01).结论 多层螺旋CT肺灌注扫描对COPD的诊断有一定的辅助作用.     

Dynamic CT scanning of the normal canine liver: interpretation of time density curves resulting from an intravenous bolus injection of contrast material

Seven adult male mongrel dogs were monitored by electromagnetic flow probes and string occluders around the hepatic artery and portal vein. Then, time density curves of the liver, aorta and portal vein were recorded using dynamic CT scanning following the bolus injection of contrast material into a peripheral vein (n = 7) and a mesenteric vein branch (n = 5). Information on total hepatic blood flow could not be obtained from the mesenteric vein injection. The hepatic time density curve could, however, be broken into its two components, hepatic arterial and portal venous flow contribution, by selective ligation of the hepatic artery or portal vein. It could be demonstrated that the arterial component of liver enhancement reached its peak at the end of the aortic wash-out of contrast material. Thus, the hepatic time-density curve could be broken in its two components by superimposing the aortic time density curve onto the hepatic curve. An attempt was made to estimate relative portal venous blood flow by using the slopes or the peaks of both components of the hepatic curve. Using the slopes of the hepatic curve resulted in a consistent underestimation of portal venous blood flow, whereas the peaks gave an estimate of portal venous flow with an accuracy within +/- 8%.     

Kinetics of a US contrast agent in benign and malignant adnexal tumors

PURPOSE: To evaluate the effects of a microbubble contrast agent on the power Doppler ultrasonographic (US) examination of adnexal tumors, with a special focus on the timing of the transit of the microbubble bolus. MATERIALS AND METHODS: Seventy patients who were suspected of having ovarian tumors were examined preoperatively with contrast material-enhanced US. Images obtained during a 5-minute examination were stored digitally, and the behavior of the contrast agent was evaluated objectively with measurement of the time-dependent image intensity at the region of interest with a computer program. A time-intensity curve in each case was derived and analyzed. The Mann-Whitney U test was used to compare intensity changes and tumor parameters in benign and malignant adnexal tumors. RESULTS: Both the baseline and maximum power Doppler intensities, as well as the absolute and relative (percent) rise in intensity, were significantly higher (P <.001) in malignant as compared with benign tumors. The arrival time was shorter (17.5 vs 22.5 seconds; P =.005) and the duration of contrast agent effect was longer (190.4 vs 103.6 seconds; P <.001) in malignant tumors than they were in benign tumors. The area under the time-intensity curve was significantly greater in malignant tumors compared with that in benign tumors (P <.001). CONCLUSION: After microbubble contrast agent injection, malignant and benign adnexal lesions behave differently in degree, onset, and duration of Doppler US enhancement.     

肾脏肿瘤患者肾动脉血流的彩色多普勒研究

目的；探讨肾脏肿瘤肾动脉血流的改变，为肿瘤的定性诊断提供一项有价值的指标。方法：运用彩色多普勒超声对32例肾肿瘤患者及30正常人的肾运用血流进行研究。结果：肾脏恶性肿瘤组肾动脉收缩期峰值流速高于肾脏良性肿瘤组及正常组（P＜0．01），阻力指数（RI）低于肾奶性肿瘤组及正常组（P＜0．01）。而肾脏奶性肿瘤组与正常组之间肾动脉的峰值血流速度及阻力指数均无明显差异。结论：肾脏恶性肿瘤患者肾动脉血流的收缩期峰值流速增高和阻力指数降低可作为其定性诊断的 一项有价值指标。     

眼眶肿瘤的氢质子磁共振波谱的临床应用研究

目的:总结眼眶病变MRS特征,研究其生化指标,以及对诊断和鉴别诊断的意义。方法:全部病例共40例,均为单发病灶,行MRI和MRS检查。术后均得到病理证实。其中良性肿瘤和类肿瘤病变30例,恶性肿瘤10例。结果:对照组和肿瘤组比较,不同的眼眶肿瘤,各化合物的变化不同,同对照组比较,眼眶肿瘤NAA均有不同程度下降(P<0.05),海绵状血管瘤下降达52.5%,而小细胞性恶性肿瘤和腺样囊性癌升高明显。良性肿瘤和恶性肿瘤的比较,Cho、Ace和Lac峰有明显差异,恶性肿瘤组明显高于良性肿瘤组。Cr峰相差不明显。Cho/Cr比值有明显增高。结论:肿瘤和正常脑组织的波谱有区别。表现在Lac、Ace的不同变化特征。良性肿瘤和恶性肿瘤的MRS波峰有明显差异,表现为Cho,Cr峰值增高,尤其是Cho/Cr比值的增高,此外Lac和Ace在恶性肿瘤增高明显,提示可作为区别肿瘤与非肿瘤的标志之一。     

Dynamic CT features of arterioportal shunts in hepatocellular carcinoma

Dynamic computed tomographic (CT) findings of 42 patients with hepatocellular carcinoma having angiographically proven arterioportal shunt were reviewed. CT findings related to arterioportal shunt were as follows: early enhancement of the portal vein, which showed a time-density curve similar to that of the aorta, markedly prolonged enhancement of the portal vein, dilated, abnormal intrahepatic vessels often accompanied by irregular, transiently enhanced areas, transient high attenuation of lobar or segmental distribution in the lobe contralateral to the main tumor, and transient wedge-shaped enhancement peripheral to the tumor. Dynamic CT usually detected arterioportal shunts involving larger portal veins as represented by any of the first four findings (14 of 17), whereas detection of arterioportal shunts involving smaller portal veins was lower in frequency (8 of 25), but such a shunt could be demonstrated as transient wedge-shaped enhancement peripheral to the tumor.     

CT灌注扫描在脑肿瘤的临床应用

目的:研究颅内良恶性肿瘤多层螺旋CT各灌注参数的改变和肿瘤良恶性和脑内外肿瘤的鉴别诊断。方法:41例患者行脑血流的CT灌注扫描,其中脑内肿瘤26例(胶质瘤6例、脑脓肿2例、脑转移瘤17例、淋巴瘤1例),脑外肿瘤15例(颅骨转移瘤2例、垂体瘤7例、脑膜瘤2例、肉芽肿3例、蛛网膜囊肿1例)。应用去卷积算法模式计算相应病变区域的血流量(BF)、血容量(BV)、平均通过时间(MTT)、毛细血管通透性(PS)。根据不同肿瘤的相关参数图来评价良恶性肿瘤血流动力学状态。结果:41例脑肿瘤患者中,脑外肿瘤的CBF、CBV和PS明显高于脑内肿瘤,脑内肿瘤的恶性程度越高其CBF和PS越高,而MTT值与良性肿瘤组织无显著差异。结论:灌注参数CBF、CBV和PS可有效的评价脑肿瘤的血流状态,在脑部良恶性病变及脑内外肿瘤的鉴别诊断上有重要的临床应用价值。