CT仿真支气管内窥镜在中央型肺癌的应用

目的：探讨螺旋CT仿真支气管内窥镜的成像技术和成像效果，及其在中央型肺癌诊断和鉴诊断中的作用。方法：39例中央型肺癌病人，全部经螺旋CT薄层扫描，所获横断面图像传输到Prominence Scientific工作站，在“三维软件”进行气管三维图像重建，然后，在工作站“飞跃”软件包进行住址内窥镜成像，结果：运用仿真内窥镜观察，39例中央型肺癌病人均显示腔内肿块的形态及气受压狭窄或阻塞的情况，正演唱 管、支气管的形态及内表面亦得以显示，结论：仿真内窥镜可以成为纤维支气管内窥镜的补充手段，在显示支气管狭窄的范围和腔外发言为方面明显优于纤维支气管内窥镜。     

低张螺旋CT扫描在诊断壶腹癌中的应用

壶腹癌是少见的胃肠道恶性肿瘤犤１犦。尸检发生率为０．２％。近年来其发病率有所上升。由于其手术切除率远高于胰腺、十二指肠肿瘤，预后好，因此壶腹癌的早期诊断非常重要。自２０００年１月～２００１年１２月采用低张螺旋CT增强扫描研究壶腹癌病变，积累了一些经验，现报告如下。１材料和方法１．１临床资料１５例壶腹癌，男９例，女６例。年龄３４～７３岁，平均５１．６岁，其中５０岁以上９例（占６０％）。临床主要症状：渐进性黄疸１５例（无痛性黄疸６例，上腹痛伴黄疸９例），上腹不适７例，乏力、纳差、体重减轻等。黄疸出现…     

动态CT增强扫描对孤立性肺结节（SPN）定性的价值

目的探讨动态CT增强扫描对孤立性肺结节（SPN）的定性价值。方法收集的50例孤立性肺结节患者为研究对象,并对所有的患者肺结节病进行同层动态CT增强扫描,分别进行平扫与增强之后的15s、75s、135s以及195s测量病灶CT值,进而观察患者病灶的时间一密度曲线,并对其进行统计学分析。结果小肺癌、肺炎性结节以及肺结核结节的平扫CT无显著性差异,增强扫描可以较为清晰的显示小肺癌与结核瘤的CT强化程度,两者具有显著性差异。小肺癌、肺炎性结节以及肺结核结节3种疾病的密度曲线形态不同。结论动态CT强化扫描能够较为清晰的显示孤立性肺结节的特征．是鉴别孤立性肺结节良、恶性的有效检查方法．值得在临床中大力的推广与应用．     

64层螺旋CT胸部低剂量扫描方案优选的多中心研究

目的 比较自动曝光控制技术(AEC)与管电流恒定技术(CCC)2种不同低剂量MSCT扫描方案对胸部CT图像质量的影响,探讨更加合理的肺低剂量扫描参数方案.方法 采用前瞻性多中心研究方法,研究对象为7所医院就诊的280例行胸部低剂量MSCT检查的受检者,设定管电流(mA)为研究变量,方法一为AEC技术,下设噪声标准差值(SD)为25(A1)及30(A2)各1组,并设定管电流上限为80 mA,下限为10 mA;方法二为CCC技术,下设40 mA(C1)及50 mA(C2)各1组;共4组,采用同一机型64层MSCT行胸部低剂量扪描.2名放射科医师应用双肓法阅片,比较2种不同扫描技术的曝光剂量、SD值,横断面、MPR的图像质量以及体质量指数(BMI)对图像质量的影响.曝光剂量及SD比较行方差分析及t检验;图像质量比较行Mann-Whitney检验;医师对图像诊断一致性检验行Kappa分析.结果 剂量长度乘积(DLP)AEC组较CCC组明显降低[(82.62±40.31)和(110.81±18.21)mGy·cm,F=56.88,P＜0.01].AEC技术中A2组DLP较A1组低[(72.77±36.68)和(92.46±41.61)mGy·cm],差异无统计学意义(t=0.82,P＞0.05).前者SD值在肺窗[(41.50±9.58)和(40.86±7.03)HU]及纵隔窗[(41.19±7.83)和(40.92±9.89)HU]均略高于后者,差异无统计学意义(F肺窗=0.835、1.910,P值均＞0.05).横断面图像质量AEC组肺窗得分除右下肺静脉水平[(4.92±0.25)和(4.93±0.17)分]、[左膈顶上缘水平(4.91±0.27)和(4.93±0.22)分]较CCC组略低外,AEC组得分均较CCC组略高[头臂静脉上缘(4.49±0.56)和(4.38±0.64)分;主动脉弓上缘(4.86±0.23)和(4.81±0.32)分;右肺上叶支气管开口(4.87±0.27)和(4.84±0.22)分;右肺中叶支气管开口(4.90±0.25)和(4.88±0.21)分],差异无统计学意义(F=0.076～1.748,P值均＞0.05);纵隔窗得分除头臂静脉上缘水平AEC组较CCC组高[(2.57±0.77)和(2.46±0.59)分],且差异有统计学意义(F=8.459,P=0.047)外,余各层面AEC组得分均较CCC组略低[(主动脉弓上缘(3.36±0.63)和(3.45±0.60)分;右肺上叶支气管开口(3.94±0.56)和(3.95±0.51)分;右肺中叶支气管开口(3.80±0.58)和(3.87±0.50)分;右下肺静脉(3.72±0.56)和(3.78±0.53)分;左膈顶上方(3.58±0.63)和(3.68 ±0.56)分],但差异均无统计学意义(F=0.083～3.380,P值均＞0.05).MPR图像质量肺窗及纵隔窗观察均略好于CCC组(Z肺窗=-2.358,Z纵隔窗=-1.330,P值均＞0.05).偏瘦、正常或偏重人群组,A1组肺窗及纵隔窗图像质量均优于A2组,差异无统计学意义(偏瘦:Z肺窗=0.000、Z纵隔窗=0.000;正常:Z肺窗=-0.062、Z纵隔窗=-0.746;偏重:Z肺窗=-1.177、Z纵隔窗=-1.715;P值均＞0.05),但在偏重人群纵隔窗图像质量A1组更好于A2组(Z=-1.715,P=0.144).结论 AEC组总曝光剂量明显低于CCC组,而AEC组的图像质量及SD值无论在肺窗或纵隔窗均与CCC组无明显差异,故建议在胸部低剂量筛查方案选择中应用AEC技术,对偏胖者宜采用SD=25方案,对正常及偏瘦者宜采用SD=30方案.

Abstract：

Objective To compare the image quality of chest low dose CT (LDCT) using automatic exposure control (AEC) and constant current control (CCC) and explore a more reasonable scanning protocol. Methods Two hundred and eighty participants were examined with 64 CT scanner at 7 centers in China. All were divided into 4 groups. Two groups underwent LDCT using AEC with standard deviation set at 25 (A1) and 30 (A2) respectively and the tube current ranged from 10 mA to 80 mA. The other two groups underwent LDCT using CCC with tube current set at 40 mA (C1) and 50 mA (C2) respectively. The axial and MPR images were evaluated by two radiologists who were blinded to the scanning protocols.The radiation dose, noise and the image quality of the 4 groups were compared and analyzed statistically.Differences of radiation dose and noise among groups were determined with variance analysis and t test,image quality with Mann-Whitney test and the consistency of diagnosis with Kappa test. Results There was a significant lower DLP in AEC group than in CCC group [(82.62±40.31)vs ( 110.81±18.21) mGy·cm (F =56. 88 ,P ＜ 0. 01 )], whereas no significant difference was observed between group A2 and group A1 0. 05]. The noisy of AEC group was higher than that of CCC group both on lung window(41.50±9.58 vs 40.86±7.03) and mediastinum window (41.19±7.83 vs 40.92±9.89), but there was no significant difference( Flung =0.835, P=0.476, Fmediastinum =1.910, P=0.128).The quality score of axial image in AEC group was higher than that in CCC group (superior margin of the brachiocephalic vein level: 4.49±0.56 vs4.38±0.64,superior margin of the aortic arch: 4.86±0.23 vs 4.81±0.32,the right superior lobar bronchus Level:4.87±0.27 vs 4. 84 ± 0. 22, the right middle lobar bronchus Level: 4.90±0.25 vs 4.88±0.21) except on the right inferior pulmonary vein level(4. 92 ±0. 25 vs 4. 93 ±0. 17) and superior margin of the left diaphragmatic dome level (4. 91±0.27 vs 4.93±0.22) on lung window, but no significant differences (F=0.076-1.748, P＞0.05) were observed. A significant higher score in AEC group was observed on mediastinum window compared with CCC group on superior margin of brachiocephalic vein level (2.57±0.77 vs 2. 46 ± 0. 59, F = 8. 459, P ＜ 0. 05 ), however, the score of AEC group was lower than that of CCC group on other levels without significant differences (superior margin of the aortic arch:3.36 ±0. 63 vs 3.45 ±0. 60,the right superior lobar bronchus level: 3.94 ±0. 56 vs 3. 95 ±0. 51 ,the right middle lobar bronchus Level: 3.80 ±0. 58 vs 3. 87 ±0. 50,the right inferior pulmonary vein level: 3.72 ±0. 56 vs 3.78 ±0. 53, superior margin of the left diaphragmatic dome level: 3.58 ± 0.63 vs 3.68±0.56,F=0.083-3.380,P ＞ 0.05 ). The MPR image quality of AEC group was better than that of CCC group both on lung window and mediastinum window (Zlung =-2.258, Zmedlastinum=-1.330, P＞0.05). For all participants including the underweighted group, the normal group and the overweighted group, the image quality of A1 group was better than that of A2 group without significant differences (the underweighted group: Zlung=0.000, P=1.000, Zmedastinum= 0.000, P=1.000;the normal group: Zlung =-0.062, P=0.950, Zmediastinum =-0.746, P = 0.456; the overweighted group: Zlung = - 1.177, P = 0.239,Zmediastinum =-1.715, P=0.144) both on lung and mediastinum windows, and for the higher BMI participants, a better image quality was obtained in A1 group than in A2 group on the mediastinum window (Z = -1. 715, P = 0. 144). Conclusions The total radiation exposure dose of AEC group is significantly lower than that of CCC group, but no statistical significant differences are observed between both groups in image quality and noise level. The AEC technique is highly recommended in thoracic LDCT scan for screening program, and the SD25 ( SD value = 25) scan protocol is suggested for higher BMI population while the SD30 (SD value = 30) scan protocol for lower BMI population.     

弥散张量纤维素成像三维重建皮质脊髓束定位脑初级运动功能区

Functional MRI (fMRI) is widely used as a non-invasive method for the evaluation of pre-operation motor function.However,patients with cortical function impairment,such as those with hemiparesis,can rarely achieve hand clenching,a typical fMRI task for central sulcus identification,and the method is also of limited use in uncooperative children.Thus,it is important to develop a new method for identifying primary motor areas (PMA) in such individuals.This study used corticospinal tractography to identify the PMA in 20 patients with deep-seated brain tumor.Two regions of interest were set within the brainstem for corticospinal tract (CST) fiber tracking:one at the level of the pons and the other at the level of the cerebral peduncle.The CST fiber tracking results and fMRI activation signals were merged with three-dimensional anatomic MRI findings.The consistency of identifying the PMA by CST and fMRI was analyzed.fMRI activation signals were distributed mainly in the contralateral central sulcus around the omega-shaped hand knob.The CST consistently propagated from the pons and cerebral peduncle to the suspected PMA location.There was a good correlation between CST fiber tracking results and fMRI activation signals in terms of their abilities to identify the PMA.The differences between fMRI and CST fiber tracking findings may result from our functional task,which consisted only of hand movements.Our results indicate that diffusion tensor imaging is a useful brain mapping technique for identifying the PMA in paralyzed patients and uncooperative children.     

64层螺旋CT血管造影在人工血管移植术后随访中的价值

目的 探讨64层螺旋CT血管造影检查在人工血管移植术后随访复查中的应用价值.方法 对23例人工血管移植术后的患者定期进行64层螺旋CT血管造影检查,利用容积再现(VR)、多平面重组(MPR)、曲面重建(CPR)、血管探针等技术方法分析移植血管的通畅情况.结果 23例患者中,5例上腔静脉综合征、4例主动脉瘤及1例布加综合征患者的移植血管在观察期内均通畅;13例下肢动脉粥样硬化患者的移植血管在观察期内3例通畅,5例轻度狭窄,2例中重度狭窄,3例闭塞.结论 64层螺旋CT血管造影检查对于人工血管移植术后的随访复查具有重要价值.     

磁敏感加权成像用于诊断非典型蛛网膜下腔出血的初步研究

目的分析非典型蛛网膜下腔出血(atypical subarachnoid hemorrhage,aSAH)在磁敏感加权成像(suscepti-bility-weighted imaging,SWI)上的影像表现,探讨SWI技术在aSAH的临床应用价值。方法分析22例接受CT和MRI(含SWI)检查并最终确诊为aSAH的患者。由两名工作10年以上具有高级职称的影像学医师分析患者CT和MRI(含SWI)数据,以判断蛛网膜下腔是否存在aSAH,并分析其影像表现。结果 SWI总共确定aSAH出血区域共47个,其中16个(34.04%)位于凸面或半球间,19个(40.43%)位于脑池,6个(12.77%)是小脑幕的蛛网膜下腔出血,6个(12.77%)位于脑室内。在脑沟或者脑池内,aSAH在SWI上表现为低信号(出血)周围环绕脑脊液信号,在较浅脑沟内可形成"三角"征;与静脉的平滑边界相比,蛛网膜下腔出血边界较粗糙,信号略显不均。aSAH在脑室内可呈现"液-液平面"。结论在SWI图上,aSAH可通过其信号和独特的形态得以确认,SWI能够提供较CT和常规MRI更多的信息显示出血少量的aSAH。     

CT与MRI在前列腺癌诊断中的应用

比较MRI及CT诊断前列腺癌的准确率。方法对48例经手术或穿刺病理证实的前列腺癌患者均行CT平扫及增强扫描,CT增强行双期动态扫描;MRI行常规扫描。将CT诊断结果与MRI诊断结果进行比较。结果 48例患者中,A期前列腺癌1例,B期前列腺癌14例,C期前列腺癌15例,D期前列腺癌18例。在15例A期或B期前列腺癌患者中,CT平扫和增强扫描直接确诊7例,诊断符合率为46.7%;MRI平扫直接确诊为13例,诊断符合率为86.7%,两者诊断符合率比较差异有统计学意义(P<0.05)。在33例C期或D期前列腺癌患者中,CT平扫和增强扫描直接确诊31例,诊断符合率为93.9%,MRI平扫直接确诊为32例,诊断符合率为96.97%,两者诊断符合率比较差异无统计学意义(P>0.05)。结论对于A或B期前列腺癌的诊断,MRI较CT有明显优势;对于C期或D期前列腺癌的诊断,CT和MRI无明显差异。     

磁敏感加权成像在颅内海绵状血管瘤诊断中的应用价值

目的 探讨磁敏感加权成像(SWI)技术在颅内海绵状血管瘤诊断中的应用价值.方法 对29例CT或MR常规检查疑有海绵状血管瘤的患者进行磁敏感加权成像序列扫描.结果 29例病例中单发者为21例,多发者为8例.其中13例为手术病理证实,其余经多位临床及影像副主任医师分别诊断为海绵状血管瘤.常规扫描发现病灶82个,其中表现为典型血管瘤征象("铁环征")为30个.磁敏感序列发现144个,其中均匀性低信号病灶117个,低信号中含有混杂信号病灶27个.结论 磁敏感加权成像对于颅内海绵状血管瘤特别是在常规MR扫描无阳性表现或不典型者具有很高的应用价值.     

原发性甲状旁腺机能减低CT表现

原发性甲状旁腺机能减低 (简称原发性甲旁低 )是一种少见、原因尚未明了的内分泌疾病 ,其临床症状隐潜 ,主要表现为手足抽搐或癫痫样发作 ,常误诊癫痫[1] 。电子计算机断层摄影 (ＣＴ)的应用 ,能提高脑质钙化的显示率 ,有助于本病的诊断。本文分析了 8例原发性甲旁低的头颅ＣＴ