BACKGROUND Fractional flow reserve (FFR) is the invasive gold standard for evaluating coronary arterial stenosis. However, there have been a few non-invasive methods such as computational fluid dynamics FFR (CFD-FFR) with coronary CT angiography (CCTA) images that can perform FFR assessment. This study aims to develop a new method based on the principle of static first-pass of CT perfusion imaging technique (SF-FFR) and evaluate the efficacy in direct comparisons between CFD-FFR and the invasive FFR. METHODS A total of 91 patients (105 coronary artery vessels) who were admitted from January 2015 to March 2019 were enrolled in this study, retrospectively. All patients underwent CCTA and invasive FFR. 64 patients (75 coronary artery vessels) were successfully analyzed. The correlation and diagnostic performance of SF-FFR method on per-vessel basis were analyzed, using invasive FFR as the gold standard. As a comparison, we also evaluated the correlation and diagnostic performance of CFD-FFR. RESULTS The SF-FFR showed a good Pearson correlation (r = 0.70, P < 0.001) and intra-class correlation (r = 0.67, P < 0.001) with the gold standard. The Bland-Altman analysis showed that the average difference between the SF-FFR and invasive FFR was 0.03 (0.11-0.16); between CFD-FFR and invasive FFR was 0.04 (-0.10-0.19). Diagnostic accuracy and area under the ROC curve on a per-vessel level were 0.89, 0.94 for SF-FFR, and 0.87, 0.89 for CFD-FFR, respectively. The SF-FFR calculation time was about 2.5 s per case while CFD calculation was about 2 min on an Nvidia Tesla V100 graphic card. CONCLUSIONS The SF-FFR method is feasible and shows high correlation compared to the gold standard. This method could simplify the calculation procedure and save time compared to the CFD method.

Department of Radiology, Beijing Friendship Hospital of Capital Medical University, Beijing 100050, China; Shukun (Beijing) Technology Company Ltd., Beijing 100102, China; Statistics Section, Beijing Friendship Hospital of Capital Medical University, Beijing 100050, China; Department of Radiology, Beijing Anzhen Hospital of Capital Medical University, Beijing 100011, China; Department of Radiology, Beijing Chest Hospital of Capital Medical University, Beijing 100010, China; Department of Cardiology, Beijing Friendship Hospital of Capital Medical University, Beijing 100050, China.

目的:研究基于线性拟合算法的医用输液泵计量校准方法,以降低医用输液泵计量校准误差.方法:根据输液泵输液多种参数有序数据点,采用线性拟合算法,研究数据点所处位置,判断医用输液泵计量是否为失配状态;当医用输液泵计量处于失配状态时,确定医用输液泵计量数学模型,分析数学模型中患者体重、药剂计量、输液瓶容量等变量的不确定度;依据医用输液泵失配和不确定度计算结果,利用反向传播(BP)神经网络的反向传播特点,建立医用输液泵计量校准模型,通过神经网络的正向传播和BP并修正模型权值,校准医用输液泵计量.结果:对比结果表明,本研究方法较甲醇气体检测仪校准方法和药品强光稳定性试验箱校准方法相比,药液滴数不确定度分别减少0.094和0.079;输液稳定性不确定度分别减少0.088和0.054;输液泵参数不确定度分别减少0.118和0.069.结论:基于线性拟合算法的医用输液泵计量校准方法与甲醇气体检测仪校准方法和药品强光稳定性试验箱校准方法相比,其输液泵计量校准误差较小,可满足医用输液泵计量校准需求.

回顾性分析2018年1月—2020年8月首都医科大学附属北京安贞医院风湿免疫科治疗的白塞综合征患者20例的临床及影像学检查资料.20例患者中,男4例,女16例,平均年龄41.2岁,平均病程17.0年.超声、CT及MR检查发现心血管系统受累13例,主要表现为主动脉瓣脱垂并重度关闭不全,主动脉瘤、主动脉假性动脉瘤、主动脉溃疡、主动脉分支血管狭窄或闭塞等;肺栓塞2例,下肢静脉血栓1例.全部患者均接受激素和/或免疫抑制剂治疗.3例行主动脉瓣置换术,术后随访6个月,发生瓣周漏1例并行二次Bentall术治疗,主动脉瓣下假性动脉瘤1例,无异常1例.2例行腹主动脉腔内隔离术治疗,术后随访1年,发现支架周围脓肿1例,支架远端假性动脉瘤1例.结果提示白塞综合征累及心血管系统时表现多样,早期诊断及手术治疗困难.临床联合应用多种无创心血管影像学检查手段,可为白塞综合征患者心血管系统受累的诊断、治疗、随访及预后评估提供全面的心血管病变影像学信息.

Objective:To evaluate the feasibility and diagnostic efficacy of the coronary fractional flow reserve derived from CT (CT-FFR) measurement method based on tracer pharmacokinetic principle.Methods:A total of 130 patients (159 coronary artery vessels) who were admitted to Beijing Anzhen Hospital from January 2015 to March 2019 were included in this study retrospectively. All patients had completed coronary CT angiography (CCTA) and invasive coronary angiography with invasive FFR. Subjective assessment of stenosis degree was performed on CCTA images and non-invasive FFR measurement was performed by using a tracer-kinetics based on CT-FFR measurement method. The Bland-Altman method was used to evaluate the diagnostic consistency of the two methods. Compared with the invasive FFR results, the sensitivity, specificity, positive predictive value, negative predictive value, and area under the ROC curve (AUC) of tracer-kinetics based on CT-FFR results for the diagnosis of coronary ischemic lesions were evaluated. All cases were divided into two heart rate groups:>65 bpm and ≤65 bpm. The diagnostic efficacy of tracer-kinetics based on CT-FFR in different heart rate groups was evaluated. χ 2 test and DeLong test were used to compare diagnostic performance in different evaluation methods and heart rate groups. Logistic regression analysis was used to evaluate the impact of factors such as heart rate, image thickness, image enhancement, and noise on the accuracy of diagnosis. Results:Bland-Altman analysis showed that the average difference between the two methods was -0.01. (-0.11-0.10). Compared with invasive FFR results, the tracer-kinetics based on CT-FFR method had a diagnostic sensitivity of 92.4%, specificity of 82.1%, positive predictive value of 87.6%, negative predictive value of 88.7%, and the area under ROC curve (AUC) value was 0.94. Compared with the diagnostic efficacy of luminal stenosis evaluated based on CCTA images, the difference was significantly statistical ( P<0.05). The diagnostic performance of CT-FFR had no statistically significant difference between the two heart rate groups. Factors such as heart rate, image thickness, image enhancement, and noise had no significant effect on the diagnostic accuracy of the tracer-kinetics based on CT-FFR method. Conclusions:The tracer-kinetics based on CT-FFR method may quickly complete the non-invasive FFR measurement on CCTA images with image quality that meets the needs of clinical diagnosis. It has a good diagnostic performance in the diagnosis of coronary ischemic lesions even for those cases with a faster heart rate. The diagnostic accuracy of tracer-kinetics based on CT-FFR method is not significantly affected by factors such as heart rate, image thickness, image enhancement, and image noise.

目的:由于子宫静脉内平滑肌瘤病(IVL)属于少见病例,其CT影像学表现有一定的特征性,回顾性分析IVL的多排CT特征及其临床表现,评价其对手术治疗的指导意义.方法:回顾性总结分析2005年至2013年间,通过外科手术及病理证实的9例IVL的患者的临床资料,多排CT特征以及病理结果.多排CT扫描参数:管电压100～ 120 kV,管电流400～450 mAs,层厚0.5 ～0.75 mm,间隔0.25～0.60 mm.监测层面放在下腔静脉右心房入口区域,手动触发开始扫描.结果:9例患者中,4例患者为子宫切除术后,1例为多发子宫肌瘤并伴子宫腺肌病.多排CT均显示蛇形的下腔静脉内充盈缺损延伸入右心房,其中1例病变延伸入右心室、肺动脉.8例病例侵犯单侧宫旁血管,1例病例侵犯双侧子宫血管,6例肿瘤沿着子宫静脉、髂静脉生长,3例病例显示病变同时波及卵巢静脉和髂静脉,9例病变均波及下腔静脉和右心房,其中1例肺动脉受累.1例患者发生肺内多发转移.结论:IVL的多排CT表现有一定特征性,9例患者均显示下腔静脉内充盈缺损延伸入右心房,CTV检查清晰地显示了IVL向子宫外生长的途径,有助于手术方案的制定.

Objective This study was designed to compare the accuracy of multi‐detector computed tomography (MDCT) and real‐time 3‐dimensional echocardiography (RT‐3DE) for left atrial (LA) volume and function assessment with magnetic resonance imaging (MRI) .Methods A total of 42 patients underwent MDCT ,MRI and RT‐3DE examina‐tions within 3 days .LAVmax ,LAVmin ,and LAEF data were obtained .Intermotality agreement was tested through Bland‐Altman analysis and paired t test .Interobserver variability was tested through Bland‐Altman analysis .Results For LAVmax ,LAVmin ,and LAEF measurements ,there was no significant difference by MDCT and RT‐3DE in comparison with MRI ( P > 0 .05) .Furthermore ,MDCT and RT‐3DE showed good intermotality agreement with MRI for LA volume and LAEF .For the interobserver variability ,MDCT was best ,then MRI ,followed RT‐3DE .Conclusion MDCT and RT‐3DE can provide highly reliable measurements of LA volume and function and information .However ,MDCT can ex‐amine coronary artery and cardiac function at the same time .

Objective To assess the value of 320⁃slice computed tomography angiography (CTA) in distinguishing hemorrhage/thrombus from lipid-rich necrotic core (LRNC) in atherosclerotic plaques of carotid artery. Methods Thirty-seven subjects who prepared to perform carotid endarterectomy (CEA), with stenosis rate about 50%-99% in at least unilateral carotid artery detected by ultrasound, were enrolled in this study. Both 320-slice CTA and 3.0T high-resolution MRI were conducted within one week before operation. CTA, MRI and pathological sections were matched with the carotid bifurcation and calcification features as the mark. According to American Heart Association (AHA) modified classification, CT slices were selected and divided into 2 groups: Type Ⅳ -Ⅴ (lipid plaques) and Type Ⅵ (hemorrhage plaques), and the density difference between lipid plaques and hemorrhage/thrombus plaques was analyzed. Results A total of 217 slices were included in final analysis, including 88 slices of Type Ⅳ -Ⅴ (lipid plaques) and 129 slices of Type Ⅵ (hemorrhage plaques). There was statistically significant difference in CT value between 2 groups. The mean CT value of lipid necrosis core in Type Ⅳ -Ⅴ and hemorrhage/thrombus in Type Ⅵ was (28.07 ± 26.84) and (97.17 ± 35.82) HU respectively, and the former was significantly lower than the latter (t = 16.141, P = 0.000). Conclusions CTA can distinguish hemorrhage/thrombus from lipid-rich necrotic core in carotid atherosclerotic plaques. doi：10.3969/j.issn.1672-6731.2014.01.005

Purpose To investigate the effect of different additional filtering on image quality,radiation dose and X-ray tube load of high-voltage adult chest radiography,screen suitable thickness of additional filtering,and optimize clinical parameter.Materials and Methods Statistic analysis of chest radiography image quality with additional filtering at different thicknesses (0,0.1,0.2,and 0.3mm) were performed in 32 patients before and after heart surgery.The skin dose and scatter radiation dose rate were measured.Results With the increase of additional filtration thickness,the patient skin dose was decreased by about 30%,and mAs was increased.Image analysis showed the image quality was consistent (P 0.01).Conclusion The patient dose can be reasonably reduced by increasing the thickness of additional copper filtration without degradation of image quality.

Objective:To evaluate the relationship between carotid stenosis and brain perfusion changes before and after revascularization,by 320 slices CT multiple segments and parameter scan.Further analysis was done to find which kind of patient can get more benefit form the carotid artery revascularization.Methods:30 patients that the ultrasound result demonstrated carotid artery stenosis underwent carotid artery revascularization.All of them studied with 320 CT multiple parameter scan 2 weeks pre and post carotid revascularization.The degree of carotid artery stenosis and CT perfusion(CTP) parameters,include(cerebral blood flow(CBF),cerebral blood volume(CBV),mean transit time(MTT),time to peak(TTP) and Delay time(Delay) were calculated.The relative value were measured.Patients were divided into two groups,Group 1 symmetry bilateral hemisphere CTP,group 2 asymmetry bilateral hemisphere CTP.Results:The relative value(rTTP、rDelay) changed obviously after carotid artery revascularization,other parameter showed no obvious change.Patients were subdivided into two groups,based on the hemodynamic changes.12 patients included in the symmetry CTP group,the hemodynamic parameters showed no obviously improvement after carotid artery revascularization,18 patients included in the asymmetry CTP group,the hemodynamic parameters(rCBV,rMTT,rTTP,rDelay) improved obviously after the operation.Conclusion:After the carotid revascularization,the morphology change of carotid artery,and the hemodynamic changes of the blood supply area,can be shown by 320 slices CT multiple parameter scan.Carotid artery stenosis patient with asymmetry CTP can get more benefit from the carotid artery revascularization.

To determine the value of dual-energy CT (DECT) and combined information of perfusion and angiography in diagnosing coronary artery disease (CAD), with single photon emission computed tomography (SPECT) and quantitative coronary angiography (QCA) as a reference standard. Thirty-four patients were enrolled in this study. DECT was used as a contrast-enhanced retrospectively ECG-gated scan protocol during the rest state and tubes were set at 140/100 kV. DECT angiography (DE-CTA) and DECT perfusion (DE-CTP) were calculated from two kV images. DE-CTP results were compared with SPECT and DE-CTA with QCA, respectively. The combined DE-CTP with DE-CTA data were compared to QCA in diagnosis of obstructive CAD (stenosis ≥ 50%). DECT showed diagnostic image quality in 31 patients. Using SPECT as a reference, DE-CTP had sensitivity of 68%, specificity of 93%, and sensitivity of 81%, and specificity of 92% for identifying any type of perfusion deficits on the segment- and territory-based analysis, respectively. Using QCA as a reference standard, DE-CTA showed sensitivity of 82%, specificity of 91% and accuracy of 86% for detecting ≥50% coronary stenosis on the vessel-based analysis, whereas the combination of DE-CTA and DE-CTP gave sensitivity of 90%, specificity of 86% and accuracy of 88% for detecting ≥50% coronary stenosis, respectively. Combination of DE-CTP and DE-CTA may improve diagnostic performance compared to CTA alone for the diagnosis of significant coronary stenosis.

Objective To evaluate the combination of dual-energy CT angiography (DE-CTA) and dual-energy CT peffusion (DE-CTP) in the diagnosis of coronary artery disease. Methods Thirty-one patients with angina pectoris were examined using dual-source dual energy CT and conventional coronary angiography. For DE-CTA, we used a contrast-enhanced ECG-gated coronary scan protocol with energy levels of two tube detector arrays at 140 and 100 kVp. Two kinds of acquired images were fused for the CT angiogram and further calculated to construct a perfusion map (Siemens DE Heart PBV). The compared the following results: DE-CTA vs. CA, DE-CTP vs. CA to assess the sensitivity and specificity, and further compared DE-CTA plus DE-CTP with CA. Results DECT obtained diagnostic image quality in 28 patients.DE-CTA detected 41/112 arterial stenosis. Using CA as a reference, the sensitivity of DE-CTA was 81%(38/47), specificity was 95% (62/65), positive predictive value was 92% (38/41), negative predictive value was 87% (62/71), and accuracy was 89% (100/112). DE-CTP detected 46 perfusion defects in artery territories. Using CA as a reference, the sensitivity of DE-CTP was 76% ( 36/47), specificity was 85% (55/65), positive predictive value was 78% (36/46), negative predictive value was 83% (55/66),and accuracy was 81% (91/112). DE-CTA plus DE-CTP diagnosed 52 arteries stenosis. Using CA as a reference, combination of DE-CTA and DE-CTP gave sensitivity of 95% ( 45/47 ), specificity of 89%(58/65) , NPV of 97% (58/60), and accuracy of 92% (103/112). Conclusions DECT can provide perfusion blood volume information as well as vessel pathology in one scan. DECT can provide comprehensive diagnosis and improve diagnosis of CAD.

Objective To investigate the accuracy of low-dose dual-source computed tomography (DSCT) coronary angiography in the step-and-shoot (SAS) mode for the diagnosis of coronary artery stenosis in comparison with conventional coronary angingraphy (CCA).Methods Prospective multiple-center study, 46 patients[mean age(58±9) years;bedy mass index(BMI) (25±3) kg/m2]underwent both DSCT in the SAS mode and CCA within 14 days.The inclusion criteria for contrast-enhanced CT: (1) heart rate less than 65 times/rain (bpm).(2) regular sinus rhythm, heart rate fluctuations within the range of 6 bpm. (3) holding breath well, breath-hold time is about 12-15 s.The exclusion criteria:(1) allergy to iodinecontaining contrast medium, nephropathy (serum creatinine level 120 μmol/L), heart failure and serious arrhythmias.(2) patients with coronary stents or bypass grafts.(3) heart rate can not be controlled very well (4)the patient could not take nitroglycerin.(5)BMI 30 kg/m2.(6) other heart disease: carcliomyopathy, valvular disease etc.Sensitivity, specificity, negative (NPV) and positive predictive value (PPV) were determined with CCA as standard of reference.The Kappa value between the two modalities and the two observers was calculated.Radiation dose values were measured.Results Mean heart rate during scanning was (61±6)bpm.99.19% (614/619) coronary segments were depicted with a diagnostic image quality. The vessel-based sensitivity, specificity, PPV, and NPV for the diagnosis of coronary artery stenosis were 96.2% (75/78), 88.2% (60/68), 90.4% (75/83), and 95.2% (60/63), respectively.The Kappa value between the two modalities was 0.848 (P=0.000).The mean effective dose of the SAS-CTCA was (2.95± 0.96) rosy(1.26-4.32 mSy).Conclusion In selected patients, DSCT coronary angiography in the SAS mode have good image quality, which allows for the accurate diagnosis of coronary stenosis at a low radiation dose.

目的探讨静脉推注美托洛尔在冠状动脉CT检查中的作用。方法受检者72例,随机分为美托洛尔静脉推注组(静脉组)和口服组各36例。静脉组推注美托洛尔总剂量10 mg,如心率下降至65次.min-1或血压下降至90/60 mmHg时,停止静脉推注美托洛尔,行冠状动脉多排CT检查;口服组一次给予美托洛尔50 mg。结果静脉组患者50.0%在用药后10 min达到目标心率,口服组中只有19.4%的患者用药后30 min达到目标心率(P<0.01)。结论静脉推注美托洛尔可以快速、有效、安全地减慢心率,使心率过快患者顺利、快速完成冠状动脉CT检查。

Objective: Review study 12 cases 240 normal pulmonary segments magne tic resonance pulmonary perfusion imaging, to have a pilot study in the method a nd the value of MRPP. Method: 12 cases that with normal nuclide pulmonary perfus ion- ventilation scan, without respiratory system disease and right ventricular functional disorder were examined with MRPA and MRPP, Setting the area of intere sting in pulmonary segment of lung field respectively, and detected signal inten sity and time-signal curve to obtain the transformation rate of signal (TROS) d uring perfusion peak value. Result: 1.The MRPP has a higher spatial resolution an d temporal resolution ,though the first pass perfusion method ,we can get the pe ak value of pulmonary parenchyma; 2.Use the transformation rate of signal (TROS) quasi- ration measure the pulmonary flow, the signal intensity of normal pulmo n ary perfusion area is symmetrical, and TROS=227%±52.32%. 3.Time-signal curve display the time of perfusion peak value is about 9.83±1.19 second. Conclusion: A higher spatial resolution and temporal resolution of MRPP is a useful method in display pulmonary circular change. It has immensurable potential advantage.