Indirect CT venography following CT pulmonary angiography: spectrum of CT findings

SUMMARY: Pulmonary embolism (PE) and deep venous thrombosis (DVT) represent two manifestations of the same syndrome, venous thromboembolism. Contrast-enhanced computed tomography (CT) angiography is a practical, efficient alternative to conventional imaging for PE. Following the pulmonary examination, the inferior vena cava (IVC) and the iliac, femoral, and popliteal veins can be studied with CT without additional intravenous contrast administration. Indirect CT venography (CTV) after CT pulmonary angiography (CTPA) simplifies and shortens venous thromboembolism work-up. Initial studies indicate that CTV is comparable to ultrasound in the evaluation of femoral/popliteal DVT. CTV has the advantage of evaluating the iliac veins and inferior vena cava, vessels poorly seen on sonography and venography. Combining CTV with CTPA increases confidence in withholding treatment when results for both the pulmonary arteries and leg veins are negative and increases the diagnosis of venous thromboembolism by 25% over CTPA alone. This pictorial essay will review the normal venous anatomy, CTV technique, and the findings of acute and chronic DVT. Interpretive pitfalls and alternative diagnoses are also reviewed.     

Virtual CT colonoscopy and virtual CT barium enema using multidetector-row CT]

CT colonography is a promising technique that provides both multiplanar and endoluminal perspective of the air-filled, distended, cleaned colon. "Virtual colonoscopy" refers to computer-simulated 3D endoscopic visualization of the colonic mucosal surface. Unlike barium enema and conventional colonoscopy, CT colonography can give cross- sectional and endoluminal images of the colon and enables to image extracolic abnormality. CT colonography offers potential advantages over colonoscopy in that it causes little discomfort to the patient, and does not need sedation. It is more accurate in spatial location of lesions and creates no complication. To date, most studies assessing CT colonography have focused in technical development, less aggressive bowel preparation, and computer-aided diagnosis of polyp detection. In the future, CT colonography would be a diagnostic and screening tool for the colorectal polyp and cancer.     

Controlling intracoronary CT number for coronary CT angiography

BackgroundControlling intracoronary computed tomography (CT) number for coronary CT angiography (CCTA) has been difficult.ObjectiveThe study assessed whether intracoronary CT number of CCTA could be estimated.MethodsOne hundred twenty six patients were randomly assigned to either CCTA with 30 mL of contrast media (CM) following 5 mL of CM at timing bolus or CCTA with 50 mL of CM following 10 mL of CM at timing bolus. The relationships between intracoronary CT number and patients’ characteristics and peak time and peak CT number at timing bolus in patients who showed valid time–density curve were analyzed in both groups. Then, the multiple regression equation best described was made. The prediction system was validated by 112 patients randomly targeted between 250 HU and 430 HU of CT number.ResultsIn group 5/30, intracoronary CT number was positively correlated with peak CT number at timing bolus (correlation coefficient, 1.42, p < 0.001), negatively correlated with body surface area (?109.19, p < 0.001) and peak time (?6.93, p < 0.001). Whereas, intracoronary CT number was positively correlated with only peak CT number at timing bolus (1.33, p < 0.001) in group 10/50. Then, CT number-controlling system using the simple equation best described CT number was established for CCTA following 5 mL of CM at timing bolus. Of 112 patients, there was good correlation between target CT number and measured CT number (r = 0.85, p < 0.0001) in 96 patients (85.7%), having valid time–density curve at timing bolus.ConclusionsControlling CT number may be enabled by CT number-controlling system following 5 mL of CM at timing bolus.     

CT enterography: state-of-the-art CT technique for small bowel imaging

Multi-detector computed tomography has become a first-line imaging modality for the evaluation of small bowel disease. Its high speed and resolution ensure excellent imaging of the small bowel with simultaneous evaluation of the lumen and wall, adjoining mesentery, and extraluminal structures in the abdominal cavity. Optimal luminal distension is an important prerequisite. Computed tomography enterography (CTE) is a dedicated adaptation for the study of the small bowel. This review discusses CTE with emphasis on procedural technique and image interpretation.     

Cardiac CT and CT coronary angiography: technology and application

Multislice computed tomography (MSCT) is an additional potential tool for the assessment of coronary artery disease. It can provide information about stenoses in coronary arteries and coronary artery bypass grafts, ventricular size and function, cardiac structure and masses, pulmonary vein anatomy, myocardial perfusion and coronary artery plaque. In this review the recent developments in CT technology that have made cardiac imaging possible are examined and the benefits of the latest 64-slice and dual-source CT scanners explained. Information on how to perform cardiac CT and evidence for its various clinical applications are given. Problems and limitations of cardiac CT and the radiation dose are discussed. Future developments and the likely impact of this rapidly evolving technique on clinical cardiology are considered.     

Coronary CT angiography

Coronary CT angiography (coronary CTA) represents an increasingly applied noninvasive method for coronary artery imaging. Due to technical development and improved spatial and temporal resolution of CT, high diagnostic value of coronary CTA is reported when compared to conventional selective angiography. The aim of this review is to present an overview of the clinical applications of coronary CTA. Important factors in patient selection and preparation are also briefly discussed.     

计算机体层摄影术观察粥样硬化性主动脉溃疡的动态变化

目的利用计算机体层摄影术(CT)研究粥样硬化性主动脉溃疡的动态变化过程,为临床治疗和预防提供有意义的依据。方法回顾分析2001年12月至2006年1月35例患者,经临床及CT检查诊断有粥样硬化性主动脉溃疡病变,其中男31例,女4例,年龄40-79(56.2±10.8)岁,随访时间7-730(平均135)天,全部患者经电子束CT(EBCT)或多排CT检查≥2次。采用Imatron C-150XP型EBCT扫描机,连续容积增强扫描,层厚6 mm/床进3.5mm或层厚3 mm/床进3 mm,扫描时间为0.1 s;或美国通用电器公司Lightspeed-16扫描机进行连续容积增强扫描,层厚3.75 mm/床进1 mm,扫描时间为0.6 s。扫描范围自主动脉弓上水平至左、右髂动脉分叉处,共120-140层。测量溃疡的深度、口径及范围。结果35例粥样硬化性主动脉溃疡患者,均因急性主动脉综合征就诊,采用CT检查明确诊断。35例患者CT诊断31例合并壁内血肿,采用保守治疗;1例弓部大溃疡保守治疗;2例行血管内膜支架隔离术治疗;1例合并主动脉弓部瘤,外科手术治疗。31例溃疡伴有壁内血肿的患者行保守治疗,CT随诊,与首次CT检查结果比较,3个月、6个月时,溃疡口径、深度、长度随时间延长分别有加大、加深、延长的趋势(均P<0.05);主动脉壁内血肿的厚度有明显吸收[首次:(11.96±4.16) mm,3个月:(7.69±4.24) mm,6个月:(3.06±1.67) mm,均P<0.05]。结论CT对粥样硬化性主动脉溃疡患者定期随访有重要的指导意义,可根据病变的特点提供最佳治疗方案。     

Enhanced CT and CT virtual endoscopy in diagnosis of heterotopic pancreas

AIM:To improve the diagnosis of heterotopic pancreas by the use of contrastenhanced computed tomography(CT)imaging and CT virtual endoscopy(CTVE).METHODS:A total of six patients with heterotopic pancreas,as confirmed by clinical pathology and immunohistochemistry in the Sixth Affiliated People's Hospital of Shanghai Jiao Tong University,Shanghai,China,were included.Nonenhanced CT and enhanced CT scanning were performed,and the resulting images were reviewed and analyzed using threedimensional postprocessing...     

Cross-modality PET/CT and contrast-enhanced CT imaging for pancreatic cancer

AIM:To explore the diagnostic value of the crossmodality fusion images provided by positron emission tomography/computed tomography(PET/CT) and contrast-enhanced CT(CECT) for pancreatic cancer(PC).METHODS:Data from 70 patients with pancreatic lesions who underwent CECT and PET/CT examinations at our hospital from August 2010 to October 2012were analyzed.PET/CECT for the cross-modality image fusion was obtained using Ture D software.The diagnostic efficiencies of PET/CT,CECT and PET/CECT were calculated and compared with each other using aχ2 test.P0.05 was considered to indicate statistical significance.RESULTS:Of the total 70 patients,50 had PC and 20had benign lesions.The differences in the sensitivity,negative predictive value(NPV),and accuracy between CECT and PET/CECT in detecting PC were statistically significant(P0.05 for each).In 15 of the 31patients with PC who underwent a surgical operation,peripancreatic vessel invasion was verified.The differences in the sensitivity,positive predictive value,NPV,and accuracy of CECT vs PET/CT and PET/CECT vs PET/CT in diagnosing peripancreatic vessel invasionwere statistically significant(P0.05 for each).In 19of the 31 patients with PC who underwent a surgical operation,regional lymph node metastasis was verified by postsurgical histology.There was no statistically significant difference among the three methods in detecting regional lymph node metastasis(P0.05for each).In 17 of the 50 patients with PC confirmed by histology or clinical follow-up,distant metastasis was confirmed.The differences in the sensitivity and NPV between CECT and PET/CECT in detecting distant metastasis were statistically significant(P0.05 for each).CONCLUSION:Cross-modality image fusion of PET/CT and CECT is a convenient and effective method that can be used to diagnose and stage PC,compensating for the defects of PET/CT and CECT when they are conducted individually.     

Rare presentation of pseudosequestration in childhood: CT and CT angiography findings

Anomalous systemic arterial supply to the lungs with normal bronchial branching and pulmonary arterial supply is an unusual variant of the sequestration spectrum. Pseudosequestration is referred as the combination of systemic arterial supply to lung with normal bronchial connection. Thorax computed tomography (CT) and CT angiography are non‐invasive and useful techniques in making the definitive diagnosis. Herein, we report two paediatric patients with anomalous systemic arterial supply to normal basal segments of the lower lobes.     

血吸虫病性肝硬化患者腹部CT表现和CT定量参数特征观察*

目的 探讨血吸虫病性肝硬化患者腹部电子计算机断层扫描(CT)表现和CT定量参数特征。方法 2018年5月～2020年5月我院收治的血吸虫病性肝硬化患者72例,其中Child-Pugh A级26例、Child-Pugh B级21例和Child-Pugh C级25例,另选择同期于我院健康体检者25名。使用飞利浦64排CT行上腹部平扫和增强扫描,选择感兴趣区,获取肝灌注参数血容量(BV)、血流量(BF)、平均通过时间(MTT)、肝动脉分数(HAF)和肝动脉灌注量(HAP)。结果 72例血吸虫病性肝硬化患者出现较典型的肝硬化CT表现、肝功能损伤的血生化学改变和脾功能亢进症表现;健康人腹部CT灌注参数BV、BF、MTT、HAF和HAP分别为(47.3±8.2)ml/100g、(211.9±42.1)ml/min/100g、(12.9±3.1)s、(0.2±0.0)和(16.3±7.9)ml/min/100g,Child-Pugh A级患者分别为(40.8±7.6)ml/100g、(183.1±37.2)ml/min/100g、(15.8±3.7)s、(0.3±0.0)和(19.1±8.8)ml/min/100g,Child-Pugh B级患者分别为(35.5±6.9)ml/100g、(124.7±33.2)ml/min/100g、(19.2±4.5)s、(0.3±0.0)和(24.5±9.9)ml/min/100g,Child-Pugh C级患者分别为(24.8±8.4)ml/100g、(115.5±28.1)ml/min/100g、(24.6±5.5)s、(0.4±0.1)和(33.5±12.5)ml/min/100g,各组间差异显著(P<0.05)。结论 对血吸虫病性肝硬化患者行CT检查能够了解肝脾形态学改变信息,测量CT灌注参数也能够为评估肝硬化的严重程度提供参考依据。