螺旋CT多平面成像技术在胫骨平台骨折诊断与治疗中的作用

目的:探讨螺旋CT多平面成像(MPR)技术在胫骨平台骨折诊断与治疗中的作用.方法:回顾性分析21例胫骨平台骨折的常规X线检查、螺旋CT扫描MPR表现、患者的手术表现及术后病人的恢复情况.结果:螺旋CT平扫MPR技术在显示胫骨平台骨折明显好于普通X线检查,结合螺旋CT扫描与MPR技术制定手术方案,术后骨折都达到良好复位.结论:螺旋CT扫描与MPR技术能更好的指导骨科医生选择胫骨平台骨折手术方式和固定器材.     

螺旋CT多平面重建、三维表面遮盖法重建技术在骨盆骨折中的临床应用

目的 :探讨 SCT、MPR、SSD在骨盆骨折应用中的价值。材料与方法 :通过对 17例骨盆骨折 SCT扫描并行 MPR及SSD重建影像分析。结果 :MPR及 SSD对骨盆骨折显示更立体、直观 ,对术前制定手术方案有重大价值。结论 :SCT扫描并 MPR及 SSD重建是骨盆骨折患者非常有价值的诊断手段     

CT多平面重建图像在腰椎间盘突出症诊断和治疗中的应用(附30例报告)

目的：探讨CT、MPR图像在腰椎间盘突出症的诊断和治疗中的应用价值。方法：2001年12月－2002年6月经CT检查的30例椎间盘突出症作MPR的矢状位、冠状位和任意曲线重建。结果：腰椎间盘突出症在CT MPR图像上分析为三型：1.铆钉型：22例；2.水滴型：5例；3.游离型：3例。结论：CT MPR能直观显示脊柱和椎管内的解剖关系，提高了定位定性的准确性，为临床治疗方案的选择提供有价值的信息。     

Analysis of perfusion defects by causes other than acute pulmonary thromboembolism on contrast-enhanced dual-energy CT in consecutive 537 patients

Objective

To assess causes, incidence and patterns of perfusion defects (PDs) on dual-energy perfusion CT angiography (DECTA) in clinically suspected acute pulmonary thromboembolisms (PTE).

Materials and methods

Consecutive 537 patients who underwent DECTA for suspicion of PTE were retrospectively reviewed. After excluding patients with possible PTE or unsatisfactory perfusion map quality, 299 patients with 1697 lobes were included. The DECTA (Somatom Definition, Siemens) was performed at 140 kV and 80 kV. Color-coded perfusion images were obtained with a lung PBV application of the workstation software (Syngo Dual Energy). The presence, incidence, three patterns of PDs (wedge-shaped, heterogeneous, and regionally homogeneous), pulmonary diseases, and the matchedness between the PD and the disease extent were studied.

Results

315 of 1697 lobes (18.6%) in 156 of 299 patients (81.3%) showed PDs. Among them, 51 (3%), 257 (15.1%), and 7 (0.4%) lobes had PDs due to vascular, nonvascular, and unidentifiable causes, respectively. Vascular causes include: pulmonary arterial (PA) hypertension (0.7%), extrinsic occlusion of PA by fibrosis (0.6%), PA hypoplasia (0.6%), vasculitis (0.5%), cancer mass compressing PA, venous occlusion, AVM, and pulmonary angiosarcoma. Most of PDs were wedge-shaped and well-matched. Nonvascular causes include: mosaic attenuation (4.1%), emphysema (3.2%), interstitial fibrosis (1.6%), bronchitis (1.4%), GGO (1.2%), cellular bronchiolitis (1%), bronchiectasis, airway obstruction, compensaroty lung hyperinflation, air trapping, cor-pulmonale, bronchopneumonia, physiologic decreased ventilation, and segmental bronchial atresia. Most of PDs showed heterogeneous pattern and were not matched.

Conclusions

Various vascular and nonvascular diseases cause PDs on DECTA. Each disease shows different pattern of PD depending on pathophysiology and physiologic compensation.     

Which concentration to choose in dual flow cardiac CT?: Dual flow cardiac CT

Purpose

An extensive number of protocols have been suggested to allow for functional diagnostics; however, no data is available about the minimal amount of contrast medium to achieve reliable imaging properties. None of the plethora of existing studies report a rational why the specific concentration was chosen.

Materials and methods

A total of 40 patients were included in this prospective, controlled study. They were divided up into four equal groups getting a different concentration (10%, 20%, 30% or 40%) of a second contrast medium bolus. Corresponding septal and right ventricular ROIs were compared. A visual score was established. Coronary attenuation was measured in the right and left coronary artery. Streak artifacts in the right atrium/ventricle were assessed.

Results

In the 10% contrast medium (CM) group only in 5/10 (50%) patients full septal delineation was reached. In all other groups full septal visualization was obtained.No group showed a relevant difference of mean density measured in HU units of the left ventricle or the coronary arteries. All study groups except of group 1 (10% CM) showed streak artifacts in the right atrium.

Conclusion

The dual flow protocol with a minimum concentration of 20% improves septal visualization as basis for left ventricular functional assessment, however, does not allow for reliable right ventricular or atrial visualization.There is no significant difference between the different concentration protocols in terms of coronary attenuation.     

Prognostic Value of Quantitative Stress Perfusion Cardiac Magnetic Resonance

Objectives

This study sought to evaluate the prognostic usefulness of visual and quantitative perfusion cardiac magnetic resonance (CMR) ischemic burden in an unselected group of patients and to assess the validity of consensus-based ischemic burden thresholds extrapolated from nuclear studies.

64排CT血管造影对烟雾病诊断价值简

目的探讨64排螺旋CT在烟雾病诊断中的临床应用价值。方法回顾性分析44例雾病病例的临床及影像资料。患者均行颅脑CT平扫和64排CTA检查。在vitrea64工作站上作容积再现（VR）、最大密度投影（MIP）、曲面重建（CPR）、和多平面重建（MPR）。结幂多层螺旋CT头血管造影均清晰显示发生狭窄、闭塞的颈内动脉、Wills环血管近侧端以及明显增多、迂曲、扩张的脑底部侧支血管网。结论综合运用多种重建技术,多层螺旋CT血管造影不仅可以清晰显示狭窄血管,还可以评价狭窄远端血管和侧支血管等情况。直观显示病变周围空间结构关系,从而为治疗提供重要的参考依据。     

16层螺旋CT多平面重组、容积重建在跟骨骨折中的应用价值

目的探讨分析16层螺旋CT多平面重组（MPR）、容积重建（VR）在跟骨骨折中的诊断价值。方法将该院2011—2014年期间,经16层螺旋CT薄层扫描并进行MPR、VR图像后处理的37例（63足）跟骨骨折病例,结合X线照片,对其影像学资料,进行回顾性分析,比较两者的诊断准确率。结果 37例（63足）跟骨骨折中,16层螺旋CT MPR及VR全部显示,X线漏诊1例。结论 16层螺旋CT MPR及VR图像在诊断跟骨骨折方面具有独特的优势,能全面、直观和立体地显示跟骨骨折,弥补了X线照片不足,提高跟骨骨折病变的诊断准确率和制定手术方案的设计提供准确的空间立体定位依据。     

颈动脉体瘤的CT多平面成像诊断

目的：探讨颈动脉体瘤的CT多平面成像表现。方法：对8例经手术病理证实为颈动脉体瘤的临床资料进行回顾性分析。结果：8个颈动脉体瘤均位于颈动脉分叉水平，术前行CT平扫和高分辨CT增强扫描并行多平面成像（MPR）处理。CT平扫表现为软组织密度肿块，呈圆形或卵圆形，边缘清楚，增强扫描肿瘤明显强化，MPR显示颈动脉分叉扩大，其中2例肿瘤向上侵犯颅底并经颈静脉孔侵入颅后窝桥小脑角区。结论：高分辨CT增强扫描加多平面成像是诊断颈动脉体瘤及其周围侵犯关系的安全、可靠的检查方法之一。     

Effect of low tube kV on radiation dose and image quality in retrospective ECG-gated coronary CT angiography

IntroductionCoronary computed tomography angiography (CCTA) has emerged as a useful diagnostic imaging modality in the assessment of coronary artery disease. However, the potential risks due to exposure to ionizing radiation associated with CCTA have raised concerns.ObjectivesCCTA can be done with low dose technique to reduce radiation exposure, without compromise of image quality or diagnostic capabilities.Material and methodsForty patients referred for CCTA were examined with low kV (100 kV for patients ?85–61 kg and 80 kV for patients ?60 kg). The dose length product (DLP) were compared with other group (40 patients) with comparable body weight, scan length and acquisition parameters. The second group was selected from PACS database, for which CCTA was done with standard 120 kV.ResultsThere was considerable reduction of radiation dose about 40% with 100 kV and 60% with 80 kV compared to standard 120 kV CCTA protocols with preserved image quality.ConclusionThe use of lower tube voltage leads to significant reduction in radiation exposure in CCTA. Image quality in non-obese patients is not negatively influenced.