多层螺旋CT冠状动脉造影的扫描技术及临床应用

目的：探讨多层螺旋CT冠状动脉造影的成像技术及临床应用价值。方法：对68例[包括40例无明显心脏疾患的志愿者，25例冠心病患者，2例经皮冠冠状动脉成形术（PTCA）术后5个月和1例主动脉瓣膜置换术后的患者]进行了多层螺旋CT冠状动脉造影（multi-slice spiral CT coronary angiography,MSSCTCA)并行冠状动脉三维重建，其中25例冠心病患者并进行了选择性冠状动脉造影检查，以此为金标准，比较MSSCTCA对冠状动脉病变的检出率（未作冠状动脉造影的，只是用于评价多层螺旋CT对冠脉各支的显示能力，如显示哪几支、显示长度，示涉及有否冠状动脉疾患的显示）。结果：MSSCTCA对冠状动脉近中段显示清晰，显示率可达90％以上；对冠状动脉狭窄检出率为87．5％。结论：MSSCTCA可作为冠状动脉粥样硬化疾患的筛选手段及冠状动脉术后复查的首选方法。     

螺旋CT三维重建方法的探讨

目的 探讨螺旋CT三维（3D）重建的方法和技巧。材料与方法 使用HiSpeed CT/i扫描机,准直1.0-5.0mm,螺距1.0-2.0,骨或标准算法,重建间隔0.1-2.0mm,应用软件功能（Advantage Windows3.1工作站）对300例病人进行了各种3D成像（包括MIP,MinIP,SSD,RaySum或叠加成像）。结论 所有病例都获得了满意的3D图像。3D重建可从不同角度和方位了解病变的形态,起源及其与周围结构的关系。结论 高质量的3D图像依赖于扫描及图像重建参数的合理选择和匹配,选择合适的重建方式及阈值,以及操作者的技巧和熟练程度。     

Low-dose spiral CT: application to surface-rendered three-dimensional imaging of central airways

PURPOSE: The purpose of this work was to assess the utility of low-dose spiral CT for three-dimensional imaging of the central airways. METHOD: Spiral CT was performed in 15 patients using two tube currents (50 and 240 mA), producing 30 CT data sets. Surface-rendered virtual bronchoscopy (VB) and shaded surface display (SSD) images were assessed by three radiologists for image quality. The radiologists were also asked to compare 15 matched pairs each of 50 and 240 mA VB and SSD images, blindly select the 240 mA image, and record differences in diagnostic quality between the matched images. RESULTS: No significant difference in image quality was noted with 50 or 240 mA. Only 51.1% of 240 mA SSD and 51.1% of 240 mA VB images were correctly identified. Differences in diagnostic quality, noted in 84.4% of SSD and 33% of VB image pairs, were not ascribed to image noise. CONCLUSION: Image quality of surface-rendered three-dimensional images of the central airways is preserved using a lower tube current.     

Multi-detector row spiral CT pulmonary angiography: comparison with single-detector row spiral CT.

PURPOSE: To compare vascular conspicuity and ability to connect pulmonary arterial branches on pulmonary angiograms obtained with helical multi-detector row computed tomography (CT) with those on pulmonary angiograms obtained with helical single-detector row CT. MATERIALS AND METHODS: Of 93 consecutive patients suspected of having pulmonary embolism, 48 underwent scanning with multi-detector row CT and 45 with single-detector row CT; scans were obtained in 9 seconds and 28 seconds with 2.5-mm and 3.0-mm collimation, respectively. The lungs were divided into three zones: central, middle, and peripheral. Two independent observers used five-point grading scales. RESULTS: Conspicuity of pulmonary arteries in the central zone was ranked equal (median of 5), but in the middle and peripheral zones it was significantly higher at multi-detector row CT than at single-detector row CT (median 5 vs 4 and 4 vs 3, P < .001, respectively). In addition, multi-detector row CT improved the ability to connect peripheral arteries with their more centrally located pulmonary artery of origin in the peripheral but not the middle zone on transverse images and in both zones on multiplanar images. Viewing with a modified window setting (width, 1,000 HU; level, -100 HU) significantly increased pulmonary arterial conspicuity. Contrast material column in the pulmonary arteries was significantly more homogeneous at multi-detector row CT. CONCLUSION: Use of multi-detector row CT significantly improves pulmonary arterial visualization in the middle and peripheral lung zones.     

颌面部复杂骨折51例螺旋CT三维重建的应用价值

颌面部复杂骨折是口腔颌面外科常见创伤,由于部位隐蔽,骨折容易漏诊误诊,因此及时准确地诊断骨折的部位、类型、移位情况,对临床制定治疗方案具有重要的指导意义。常规CT的轴位图像观察有一定的局限性,螺旋CT（multislicec computed tomography,MSCT）以其先进的扫描技术和强大的软件重建功能能够将隐蔽部位的骨折通过三维显示其结构形态,以指导临床制定手术方案。     

大肠充气螺旋CT扫描图像后处理功能的临床应用

目的 探讨大肠充气螺旋ＣＴ图像后处理功能在大肠病变检查中的临床价值。方法 ３４例经手术病理证实的大肠癌及大肠息肉患者进行了大肠充气螺旋ＣＴ扫描及空气投影成像（ａｉｒ ｃａｓｔ ｉｍａｇｉｎｇ ＡＣＩ）、ＣＴ仿真内窥镜（ＣＴ ｖｉｒｔｕａｌｅｎｄｏｓｃｏｐｙ,ＣＴＶＥ）、多层面重建技术（ｍｕｌｔｉｐｌｅ ｐｌａｎｎｅｒｒｅｃｏｎｓｔｒｕｃｔｉｏｎ,ＭＰＲ）３种图像后处理,并分别与手术病理结果比较。     

螺旋CT彩色三维图像打印技术探讨

目的 探讨螺旋CT彩色三维(3D)图像打印技术。方法 使用美国Marconi螺旋CT、1台个人计算机、1台彩色喷墨打印机、1台交换机，对136例病人进行了各部位的3D彩图打印。结果 所有病例使用此方法打印出的彩色3D图像都获得了满意的效果。结论 此方法经济、简便又实用，而且能较好的满足临床诊断及手术需求。     

Comparison of helical and serial CT with regard to three-dimensional imaging of musculoskeletal anatomy.

To test the hypothesis that helical computed tomographic (CT) scans provide three-dimensional images as good as or better than those provided by serial CT, two objects were used to study the effects of helical CT: an angled cylindrical bone phantom and a human cadaveric femur specimen with a simulated fracture 1 mm wide. Both objects were immersed in a water bath, and a series of helical and serial CT scans were obtained with various parameters. Volumetric rendering was applied to the resultant data sets to create three-dimensional images, which three radiologists reviewed in a blinded manner to rate their fidelity, accuracy, and diagnostic usefulness. As expected, the images obtained with thin collimation and small intersection spacing or slow table movement were considered superior. Helical and serial CT data acquired with similar parameters were similar in quality, but helical CT is approximately five times faster than serial CT; hence, it is possible to use thinner collimation and obtain more sectional data with helical CT.     

多层螺旋CT肝动脉三维重建的临床价值

随着多层螺旋CT（MSCT）及其后处理工作站的应用，利用三维重建图像可获得清晰的肝动脉及其分支的图像．为肝癌的介入治疗或手术计划的制定提供重要信息。 1 资料与方法     

容积重建法CT脑血管造影的临床应用

目的：探讨CT三维容积重建（volume rendering,VR)脑血管造影的成像方法，评价其临床价值。方法：分析62例CT三维容积重建法脑血管造影的图像，三维观察正常血管及血管病变显示情况，同时与表面遮盖法（surface shade display,SSD)，最大强度投影法（maximum intensity project,MIP)图像比较，并对照DSA和（或）手术结果。结果：VR法脑血管造影显示及脑血管分支清楚，走行自然，能透过骨结构显示血管管腔，血管之间，血管与周围器官的相互关系，显示脑血管病变50例，显示率80．6％，与DSA或手术结果对照，48例诊断正确，2例假阳性，诊断正确率为96．0％，VR图像脑血管的显示与SSD，MIP比较差异无显著性意义（P＞0．25）。结论：VR法脑血管造影是最新的快速而有效的无创伤性三维血管成像术，能部分替代并弥补DSA，VR 旬具有显示血管管腔，重叠血管及避免去骨处理等优点。     

3D-DA与3D-MSCTA对颅内动脉瘤诊断价值探讨

目的 探讨三维数字血管造影(3D-DA)与三维多层螺旋CT血管造影(3D-MSCTA)在颅内动脉瘤诊断中的作用和意义.方法 回顾性分析2008年12月- 2010年12月41例疑似颅内动脉瘤患者的常规DSA、3D-DA及3D-MSCTA影像资料,分别由2名放射科医师采用双盲法进行分析并咨询神经外科医师.评估两种方法检测...     

SPECT-CT: applications in musculoskeletal radiology

This article reviews the technique, basic science principles and applications of integrated single photon emission CT (SPECT)-CT in musculoskeletal radiology. A review of the current evidence on the topic was undertaken, and selected clinical cases from the authors'' institution have been used for illustration. SPECT-CT is a technology with emerging applications that offers technical advantages to image fusion of separately acquired SPECT and CT studies. The prevailing evidence indicates that there may be benefit in adding SPECT-CT to conventional imaging algorithms during the evaluation of some malignant and benign musculoskeletal conditions. SPECT-CT can improve both sensitivity and specificity by reducing equivocal interpretation in comparison to planar scintigraphy or SPECT alone. The evidence base for SPECT-CT in musculoskeletal radiology is still evolving. There is a lack of evidence comparing SPECT-CT with MRI in many key indications, and further research is required in these areas.A wide range of pathological conditions may affect the musculoskeletal system, including infection, trauma and malignant disease. Advances in MRI, multidetector CT (MDCT) and high-frequency ultrasound have provided considerable improvements in imaging musculoskeletal disease over the past decade. There are, however, limitations associated with each of these techniques. MRI image acquisition remains relatively time consuming and, particularly in musculoskeletal radiology, image quality can be degraded significantly by metal artefact from internal fixation and prostheses. MDCT offers exquisite characterisation of bone and can rapidly generate high-quality three-dimensional reconstructions; however, the contrast resolution for soft tissues is limited and the modality can also suffer metal-related artefact, although like MRI, imaging parameters can be adjusted to reduce this artefact. High-frequency ultrasound, although operator dependent, provides excellent spatial and contrast resolution for superficial structures but is suboptimal for deeper structures and is unable to penetrate cortical bone.Bone scintigraphy remains an important and highly sensitive tool to the musculoskeletal radiologist but this is frequently criticized for its lack of specificity. Radionuclide imaging, however, may be the only modality to demonstrate pathology before it becomes evident on anatomical imaging. Developments in gamma camera technology now allow high-resolution imaging with shortened scan times, and single photon emission CT (SPECT) imaging has become commonplace in the UK. SPECT is able to increase sensitivity further and improves lesion localisation, but the paucity of anatomical markers on radionuclide imaging remains a constant challenge. Thus, the importance of correlating anatomical and functional imaging has become increasingly recognised [1].Use of a combined SPECT/CT system allows for sequential acquisition of both anatomical and functional information with a high degree of image fusion accuracy.In this article, we briefly review the technique, basic science principles and technical challenges of SPECT-CT, and discuss the applications of this hybrid modality in musculoskeletal radiology.     

Volume-rendered multidetector CT angiography: noninvasive follow-up of patients treated with renal artery stents

OBJECTIVE: The purpose of our study was to evaluate the role of multidetector CT (MDCT) angiography with volume rendering for estimating the patency of renal artery stents. SUBJECTS AND METHODS: In 16 patients, 16 renal artery stents were evaluated with MDCT renal angiography and digital subtraction angiography (DSA). CT data were evaluated using multiplanar volume reformations and the volume-rendering algorithm with three different volume-rendered parameter settings (low-to-high, high-to-low, and high-low-high opacity transfer functions: VR(LH), VR(HL), and VR(VE), respectively). Targeted images of each stent were rendered in paraaxial and paracoronal planes and were interactively interpreted. The overall restenosis severity was measured on postprocessed paraaxial and paracoronal images and compared with that obtained on DSA using linear regression analysis. Image quality and lumen delineation on rendered images were also compared using Wilcoxon's signed rank test. RESULTS: Eight restenoses were identified on DSA. Correlations between restenosis severity measured with DSA and those measured with MDCT were significant (p < 0.001). Volume rendering with VR(HL) allowed the best correlation with DSA (reviewer 1, r(2) = 0.86; reviewer 2, r(2) = 0.94) and was significantly better than multiplanar volume reformations (p = 0.028). Overall image quality was high with all rendering techniques and with no significant differences (p > 0.59, for all comparisons). Stent lumen was well delineated with volume-rendering modalities; however, VR(HL) was significantly better than VR(LH) (p = 0.033). CONCLUSION: Volume-rendered MDCT angiography enabled high-quality three-dimensional reproducible evaluation of the patency of implanted renal artery stents. Volume rendering with VR(HL) achieved the best performance.     

多层螺旋CT三维重建对颈椎外伤的诊断价值

目的探讨多层螺旋CT三维重建对颈椎外伤的诊断价值。方法回顾性分析40例颈椎骨折合并脱位患者的临床、X线平片、MRI检查、多层螺旋CT三维图像资料,利用容积再现（VR）、多平面重建（MPR）和3D技术观察骨折及脱位的情况和毗邻关系。结果40例的多层螺旋CT三维图像资料均能清楚显示骨折的部位、类型、严重性、移位程度及相应的软组织损伤情况,其中4例线形骨折X线平片及MRI检查均未能清楚显示骨折的具体部位。结论多层螺旋CT三维重建对颈椎骨折、骨与关节骨折的显示与x线平片比较具有明显优势,较容易判断骨折的程度和范围,对临床医师合理制定手术方案有较强的指导意义。     

三维CT重建对经皮椎体后凸成形术的指导价值

目的 探讨三维CT重建对经皮椎体后凸成形术(PKP)的指导价值.方法 准备行经皮椎体后凸成形术的24例患者,术前行病变椎体的三维CT重建.结果 根据三维CT重建结果,11例患者为手术禁忌而放弃行PKP治疗,其他13例患者经测量得到相应数据,为手术者提供了精确的定位.结论 螺旋三维CT重建对PKP有着较高的指导价值.     

不规则骨骨折螺旋CT三维重建与X线平片对照研究

目的:评价螺旋CT三维重建技术对不规则骨骨折应用的价值。方法:回顾性对照分析了46例不规则骨骨折的X线平片、螺旋CT多层面容积重建(MPVR)和表面遮盖显示(SSD)图像。结果:46例中,髋骨7例、坐骨1例、耻骨4例、腕骨3例、肩胛骨7例、锁骨6例、跗骨9例、颜面骨6例和髌骨3例。X线阳性诊断率仅41.3％,可疑、假阳性及假阴性高达58.7％。结论:螺旋CT的MPVR及SSD三维重建技术对不规则骨骨折有重要的临床应用价值。     

64层螺旋CT三维重建在气管主支气管肿瘤诊断中的应用

目的 探讨64层螺旋CT三维重建在气管、主支气管肿瘤诊断中的应用价值.方法 39例均接受64层螺旋CT胸部扫描,工作站行气管、支气管三维重建,仿真内窥镜,多平面重组,最小密度投影重建.分析气管、支气管肿瘤的CT表现,并与手术病理和支气管镜检结果进行比较.结果 肿瘤位于气管9例,左主支气管13例,右主支气管15例,病变广泛2例.所有病例均见管腔内充盈缺损影,致管腔1级狭窄1例,2级狭窄0例,3级狭窄14例,4级狭窄24例.管壁无增厚2例,管壁增厚14例,壁厚伴向轮廓外突出23例.宽基底32例,窄基底7例.边缘光滑2例,边缘不规则37例.良性肿瘤3例:良性间叶瘤、平滑肌瘤、多形性腺瘤各1例.恶性病变36例:小细胞未分化癌8例,腺癌1例,鳞状细胞癌25例,黏液表皮样癌1例,甲状腺乳头状癌1例.与病理比较本研究正确诊断率为97.44%,与支气管镜检比较仿真内窥镜对病变近端的显示与支气管镜所见均一致.结论 64层螺旋CT三维重建是气管、主支气管良恶性肿瘤诊断与鉴别诊断、支架植入计划和疗效评价的方便、无创、准确的检查方法.     

16层螺旋CT重建技术在寰枢椎损伤中的诊断价值

目的:探讨16层螺旋CT及重建技术在寰枢椎损伤中的诊断价值。方法:回顾性分析我院33例寰枢椎损伤患者的16层螺旋CT资料。结果:33例寰枢椎损伤中12例为多处骨折,4例单纯性寰枢关节半脱位,C1骨折13例共17处,C2骨折16例24处,C2齿状突Ⅱ型骨折致寰枢椎脱位6例。轴位CT、多平面重建(MPR)、曲面重建(CPR)、容积再现(VRT)显示单纯性寰枢椎关节脱位3、4、4、4处以及C1骨折17、16、17、16处以及C2骨折22、24、24、19处以及齿状突Ⅱ型骨折致寰枢椎脱位5、6、6、6处。结论:16层螺旋CT扫描和三维重建,可清晰显示寰枢椎骨折及脱位情况,可作为寰枢椎损伤检查的首选。