Radiation dose analysis of computed tomography coronary angiography in Children with Kawasaki disease

BACKGROUND There is evolving role of computed tomography coronary angiography(CTCA)in non-invasive evaluation of coronary artery abnormalities in children with Kawasaki disease(KD).Despite this,there is lack of data on radiation dose in this group of children undergoing CTCA.AIM To audit the radiation dose of CTCA in children with KD.METHODS Study(December 2013-February 2018)was performed on dual source CT scanner using adaptive prospective electrocardiography-triggering.The dose length product(DLP in milligray-centimeters-mGy.cm)was recorded.Effective radiation dose(millisieverts-mSv)was calculated by applying appropriate age adjusted conversion factors as per recommendations of International Commission on Radiological Protection.Radiation dose was compared across the groups(0-1,1-5,5-10,and>10 years).RESULTS Eighty-five children(71 boys,14 girls)with KD underwent CTCA.The median age was 5 years(range,2 mo-11 years).Median DLP and effective dose was 21 mGy.cm,interquartile ranges(IQR)=15(13,28)and 0.83 mSv,IQR=0.33(0.68,1.01)respectively.Mean DLP increased significantly across the age groups.Mean effective dose in infants(0.63 mSv)was significantly lower than the other age groups(1-5 years 0.85 mSv,5-10 years 1.04 mSv,and>10 years 1.38 mSv)(P<0.05).There was no significant difference in the effective dose between the other groups of children.All the CTCA studies were of diagnostic quality.No child required a repeat examination.CONCLUSION CTCA is feasible with submillisievert radiation dose in most children with KD.Thus,CTCA has the potential to be an important adjunctive imaging modality in children with KD.

Coronary computed tomography angiography in coronary artery disease

AIM: To investigate the research directions of coronary computed tomography (CT) angiography in the diagnosis of coronary artery disease (CAD) based on a systematic review of the literature.METHODS: A search of articles on coronary CT angiography in the diagnosis of CAD was performed during a 6-year-period between 2005 and 2010 from f ive main radiology journals namely, Radiology, American Journal of Roentgenology, European Radiology, European Journal of Radiology and British Journal of Radiology. Analysis of the references was focused on the research directions of coronary CT angiography with regard to the type of studies in terms of diagnostic value, application of dose-reduction strategies and resultant effective radiation doses with use of these techniques.RESULTS: One hundred and forty two studies were identified which met the selection criteria and were included in the analysis. 64-slice CT (single source anddual-source CT) dominated 78% of the coronary CT angiography studies. Prior to 2007, research was focused on the diagnostic value of coronary CT angiography, but since 2008 more attention has been paid to radiation dose reduction. Radiation dose was reported in 64 studies, representing 45% of total studies published in the f ive radiology journals. Various dose-saving strategies have been implemented and prospective electrocardiography-triggering and high pitch techniques were found to be the most effective approaches for radiation dose reduction, with the corresponding mean effective dose being 3.5 ± 1.9 mSv and 1.7 ± 0.6 mSv, respectively.CONCLUSION: This review shows that the current research in coronary CT angiography has shifted from the previous focus on diagnostic accuracy in CAD to more emphasis on radiation dose reduction.

Effects of combining multiple dose reduction techniques on coronary computed tomography angiography

BACKGROUND Coronary computed tomography angiography(CCTA)is the preferred noninvasive examination method for coronary heart disease.However,the radiation from computed tomography has become a concern since public awareness of radiation hazards continue to increase.AIM To explore the value of multiple dose reduction techniques for CCTA.METHODS Consecutive normal and overweight patients were prospectively divided into two groups:Group A1,patients who received multiple dose reduction scans(n=82);and group A2,patients who received conventional scans(n=39).The scan parameters for group A1 were as follows:Isocentric scan,tube voltage=80 kV,and tube current control using 80%smart milliampere.The scan parameters for group A2 were as follows:Normal position,tube voltage=100 kV,and smart milliampere.RESULTS The average effective doses(EDs)for groups A1 and A2 were 1.13±0.35 and 3.36±1.30 mSv,respectively.There was a statistically significant difference in ED between the two groups(P<0.01).Furthermore,noise was significantly lower,and both signal-to-noise ratio and contrast signal-to-noise ratio were higher in group A2 when compared to group A1(P<0.01).Moreover,the subjective image quality(IQ)scores were excellent in both groups,in which there was no significant difference in subjective IQ score between the two groups(P=0.12).CONCLUSION Multiple dose reduction scan techniques can significantly decrease the ED of patients receiving CCTA examinations for clinical diagnosis.

Multislice CT angiography in coronary artery disease: Technical developments, radiation dose and diagnostic value

Multislice computed tomography (CT) angiography has been increasingly used in the detection and diagnosis of coronary artery disease because of its rapid technical evolution from the early generation of 4-slice CT scanners to the latest models such as 64-slice, 256-slice and 320-slice CT scanners. Technical developments of multislice CT imaging enable improved diagnostic value in the detection of coronary artery disease, and this indicates that multislice CT can be used as a reliable lessinvasive alternative to invasive coronary angiography in selected patients. In addition, multislice CT angiography has played a significant role in the prediction of disease progression and cardiac events. Despite promising results reported in the literature, multislice CT has the disadvantage of having a high radiation dose which could contribute to the radiation-induced malignancy. A variety of strategies have been currently undertaken to reduce the radiation dose associated with multislice CT coronary angiography while in the meantime acquiring diagnostic images. In this article, the author will review the technical developments, radiation dose associated with multislice CT coronary angiography, and strategies to reduce radiation dose. The diagnostic and prognostic value of multislice CT angiography in coronary artery disease is briefly discussed, and future directions of multislice CT angiography in the diagnosis of coronary artery disease will also be highlighted.

Sixty-four-multi-detector computed tomography diagnosis of coronary artery anomalies in 66 patients

Background The abnormalities of coronary arteries, though rare and sometimes benign, may first present clinically as myocardial infarction or sudden death. Multi-detector computed tomography （MDCT） is a non-invasive test that is highly suitable for detecting these anomalies. The study aimed to review the 64-MDCT appearance of the coronary artery anomalies in 66 patients and to discuss the clinical importance of these anomalies.Methods In 6014 consecutive patients examined over 12 months by 64-MDCT for the study of coronary artery disease, 66 were diagnosed for coronary artery anomalies. All patients were symptomatic for one or more of the following diseases： chest pain, dyspnoea, palpitations, arrhythmia and myocardial infarction. Nine patients had undergone a coronary angiography. All the CT images were evaluated by two radiologists and one cardiologist. The right coronary artery （RCA） and the conus branch arising separately, myocardial bridging and duplication of arteries were not analysed in our study.Results The incidence of coronary artery anomalies found in our study group was 1.097%. In the selected patients, seven different types of coronary anomalies were found by 64-MDCT examination. The high takeoff, origin of the coronary artery from the opposite or noncoronary sinus with an anomalous course, and coronary artery fistula were the three common forms of anomalies （n=16, 18 and 16, respectively）. Compared with the results of the coronary angiography, the number of the drainage sites of two coronary artery fistula was less in MDCT images （3 small sites in total）. In all cases, coronary artery computed tomography angiography （CTA） technique was able to recognize the origin of the coronary artery, its three-dimensional course and its spatial relationship with the adjacent structures. Conventional coronary angiography in two cases, however, was unable to provide sufficient information for correct and complete diagnosis.Conclusions In conclusion, the study showed that 64-MDCT, especially the volume rendering technique （VRT）, may be useful for the assessment of complex variations, even if the conventional angiography may not be sufficient. It may be considered as the first-choice imaging modality when an anomalous coronary artery is suspected.

Use of coronary CT angiography in the diagnosis of patients with suspected coronary artery disease： findings and clinical indications

Objective To investigate the clinical applications of coronary CT angiography in patients with suspected coronary artery disease and identify factors that affect CT findings. Methods Medical records of patients suspected of coronary artery disease over a period of 12 months from a tertiary teaching hospital were retrospectively reviewed. Patient age, sex （male/female）, duration of symptoms and abnormal rates of coronary CT angiography scans were analysed to investigate the relationship among these parameters. The patients by age were characterized into five groups： under 36 years, 36-45 years, 46-55 years, 56455 years and more than 66 years, respectively; while the duration of symptoms was also classified into five groups： less than one week, one week to one month, one to three months, three to six months and more than six months. Results Of the 880 patient records reviewed, 800 met the above study criteria. Five hundred and forty nine patients demonstrated abnormal CT findings （68.6%）. There was no significant difference in the percentage of abnormal CT findings based on patient sex and the duration of symptoms （P = 0.14）. The abnormal rates of coronary CT angiography, however, increased significantly with increasing age （P 〈 0.001）; with patients over 65 years of age 2.5 times more likely to have an abnormal CT scan relative to a patient under 45 years. A significant difference was found between abnormal coronary CT angiography and the duration of symptoms （P = 0.012）. Conclusions Our results indicate coronary CT angiography findings are significantly related to the patient age group and duration of symptoms. Clinical referral for coronary CT angiography of patients with suspected coronary artery disease needs to be justified with regard to the judicious use of this imaging modality.

Radiation dose measurements in coronary CT angiography

Coronary computed tomography(CT)angiography has been recognized as the most rapidly developed imaging technique in the diagnosis of coronary artery disease due to the emergence and technological advances in multislice CT scanners.Coronary CT angiography has been confirmed to demonstrate high diagnostic and predictive value in coronary artery disease when compared to invasive coronary angiography.However,it suffers from high radiation dose which raises concerns in the medical field.Various dose-reduction strategies have been proposed with effective outcomes having been achieved to reduce radiation exposure to patients.This article provides an introduction and overview of the series of articles that will focus on each particular topic related to coronary CT angiography.

Assessment of a Sudden Death Case due to Coronary Artery Disease Based on the PMCT and Forensic Autopsy

It is never an easy thing to diagnose heart vascular disease only depending on the unenhanced postmortem computed tomography(PMCT).This article reported a case of sudden natural death after the complaint of anterior chest pain in which coronary artery calcification(CAC) was clearly displayed using PMCT scan.The entire coronary artery system was almost reconstructed via multiplanar reformation(MPR) and volume-rendering reconstruction(VR),and the total calcium score of the coronary arteries was obtained with CaScoring automatic analysis software.The results showed that CAC was conspicuous;the total calcium score was 640.3,considerably higher than 400.The pulmonary ground-glass opacity(GGO) and small amount of fluid both in the subglottic trachea and main bronchi were also found.The imaging results confirmed those of autopsy.In addition,the results concluded that PMCT might serve as an invaluable adjunct to the classic autopsy procedure.

心律不齐患者自适应前瞻性心电触发窄窗冠状动脉CT血管成像扫描的可行性

目的分析心律不齐患者行冠状动脉CT血管成像检查中采用前瞻性心电触发扫描的应用效果。资料与方法前瞻性选择2017年5月—2020年5月首都医科大学宣武医院收诊的心律不齐患者124例,随机分为两组,对照组58例采用回顾性心电门控冠状动脉检查;研究组66例采用前瞻性心电触发扫描,比较两组诊断结果、图像质量评分、对比剂用量和辐射剂量情况。结果两组诊断准确率均在95%以上,差异无统计学意义(P>0.05);研究组患者左前降支、左回旋支、右冠状动脉图像质量与对照组一致,平均主观评分分别为4.16比4.07、3.98比4.22、4.03比4.01,但对比剂用量、有效辐射剂量均明显低于对照组,分别减少29%和39%,差异均有统计学意义(t=32.811、9.119,P=0.001)。结论对于心律不齐患者,前瞻性心电触发扫描窄窗技术保证冠状动脉成像的图像质量,与常规回顾式扫描诊断准确性相当,同时能提高检查安全性,减少辐射剂量。

超高端螺旋CT单心跳心脏技术判别冠脉狭窄和斑块性质的临床价值及合并基础疾病对准确性的影响

目的:研究超高端螺旋CT单心跳心脏技术判别冠脉狭窄和斑块性质的临床价值及合并基础疾病对准确性的影响。方法:本研究采用前瞻性研究方法,以我院2022年7月—2023年1月诊断并进行治疗的冠心病患者96例作为研究对象,根据患者的冠脉狭窄程度,Ⅰ级病变患者33例,Ⅱ级病变患者22例,Ⅲ级病变患者41例。根据斑块性质分析,其中稳定性斑块患者55例,不稳定性斑块患者41例,所有患者入组后均接受256排CT行单心跳心脏冠脉成像、冠脉造影(ICA)和血管内超声(IVUS)检查,比较单心跳心脏冠脉成像诊断冠脉血管狭窄以及不稳定性斑块的诊断效能,研究合并基础疾病对准确性的影响。结果:本研究中,单心跳心脏冠脉成像诊断冠脉血管狭窄Ⅲ级病变的灵敏度为80.49%,单心跳心脏冠脉成像诊断冠脉血管狭窄Ⅲ级病变的ROC曲线下面积为0.771,合并高血压、糖尿病、高脂血症等,会造成单心跳心脏冠脉成像诊断冠脉血管狭窄Ⅲ级病变的效能下降。单心跳心脏冠脉成像诊断冠脉血管不稳定斑块的灵敏度为80.21%,单心跳心脏冠脉成像诊断冠脉血管不稳定斑块的ROC曲线下面积为0.775,合并高血压、糖尿病、高脂血症等,会造成单心跳心脏冠脉成像诊断冠脉血管不稳定斑块的诊断效能下降。结论:超高端螺旋CT单心跳心脏技术判别冠脉狭窄和斑块性质的灵敏度均超过80%以上,合并高血压、糖尿病以及高脂血症患者,会造成冠脉狭窄和斑块性质的判定准确性以及灵敏度的下降。

冠状动脉CT血管造影及血清指标对冠心病冠状动脉狭窄程度的评价

目的:探讨冠状动脉CT血管造影(CCTA)及血清脂蛋白相关磷脂酶A2(Lp-PLA2)、血管生成素样蛋白3(ANGPTL3)对冠心病冠状动脉狭窄程度的评价。方法:选取2022年7月至2023年3月河北省胸科医院诊治的102例冠心病患者,按照冠状动脉狭窄程度积分(Gensini积分)情况将其分为轻度组(0分≤Gensini积分≤20分)、中度组(20分<Gensini积分≤60分)及重度组(Gensini积分>60分),每组34例。对比3组患者冠状动脉最小管腔直径(MLD)、狭窄面积百分比(%AS)、狭窄直径百分比(%DS)、最小管腔面积(MLA)、Lp-PLA2及ANGPTL3,根据受试者工作特征(ROC)曲线,预测冠状动脉狭窄程度的诊断效能。结果:重度组MLA、MLD低于中度组和轻度组,而%AS、%DS高于中度组和轻度组,差异有统计学意义(t=6.905、4.083、5.871、6.976、3.387、2.198、2.668、3.505,P<0.05)。重度组Lp-PLA2、ANGPTL3高于中度组和轻度组,差异有统计学意义(t=4.164、8.220、2.575、3.050,P<0.05)。ROC曲线分析显示,MLA、MLD、%AS、%DS、CCTA综合参数、LpPLA2以及ANGPTL3预测冠状动脉狭窄程度的ROC曲线下面积(AUC)值分别为0.838、0.690、0.742、0.801、0.904、0.808和0.807。灵敏度分别为91.20%、91.20%、64.70%、94.10%、97.10%、70.60%和88.20%;特异度分别为76.50%、57.40%、75.00%、50.00%、70.60%、97.10%和70.60%。CCTA综合参数的AUC分别高于LpPLA2和ANGPTL3,但差异无统计学意义(P>0.05)。结论:CCTA及血清Lp-PLA2、ANGPTL3评估冠心病冠状动脉狭窄程度均具有一定效能,且CCTA的预测效能更高。

Coronary CT angiography:Beyond morphological stenosis analysis

With the introduction of 64- and post-64 slice computed tomography(CT)technology,coronary CT angiography has been increasingly used as a less invasive modality for the diagnosis of coronary artery disease.Despite its high diagnostic value and promising results compared to invasive coronary angiography,coronary CT angiography is associated with high radiation dose,leading to potential risk of radiation-induced cancer.A variety of dose-reduction strategies have been reported recently to reduce radiation dose with effective outcomes having been achieved.This article presents an overview of the various methods currently used for radiation dose reduction.

CT冠状动脉成像中钙化斑块特征对血管狭窄诊断结果的影响

【目的】探讨CT冠状动脉成像中钙化斑块特征对血管狭窄诊断结果的影响。【方法】本院收治的102例存在钙化斑块的冠心病患者作为观察组,另选取本院同期接受治疗的80例无钙化斑块的冠心病患者为对照组。所有患者均行CT冠状动脉成像和数字减影血管造影(DSA)检查钙化斑块特征,分析不同程度斑块钙化对CT冠脉造影诊断血管狭窄程度的影响。【结果】观察组102例有钙化斑块的冠心病患者中,共189处出现狭窄情况,其中由非钙化斑块引起的狭窄54处,轻中度钙化斑块引起的狭窄78处,重度钙化斑块引起的狭窄57处。CT冠脉造影诊断结果对于非钙化斑块的诊断与DSA诊断的一致性高(Kappa=0.904,P<0.05),对轻中度钙化斑块与DSA诊断一致性较高(Kappa=0.822,P<0.05),对重度斑块与DSA诊断一致性一般(Kappa=0.541,P<0.05)。对照组80例患者,经DSA诊断,共98处发生狭窄,其中53处为不明显狭窄,45处为明显狭窄。CT冠脉造影与DSA诊断结果一致性较高(Kappa=0.979,P<0.05)。轻中度钙化斑块与重度钙化斑块的灵敏度比较,差异无统计学意义(P>0.05);轻中度、重度钙化斑块诊断的特异性和准确率比较,差异有统计学意义(P<0.05)。【结论】在钙化斑块存在的情况下,CT冠脉造影诊断血管狭窄的敏感性较高,特异性较低,且重度钙化斑块存在对特异性的影响较为严重。

冠状动脉计算机体层血管成像对冠心病的诊断价值

目的分析冠状动脉计算机体层血管成像(Computed Tomography Angiography,CTA)在冠心病中的诊断价值。方法选取2021年5月至2023年10月黎平县人民医院收治的104例可疑冠心病患者,均接受冠状动脉造影(Coronary Angiography,CAG)和CTA检查。评估CTA的诊断效能,冠状动脉CTA病变部位分布和病变严重程度的检出率。结果DSA检查示阳性94例,阴性10例;CTA检查示阳性92例,阴性12例,以CAG作为冠心病诊断的金标准,CTA检查的灵敏度为96.81%(91/94),特异度为90.00%(9/10),准确率为96.15%。以CAG作为冠心病诊断的金标准,CAG检出阳性冠状动脉201例,CTA检出阳性冠状动脉196例,总检出率为97.51%;CTA检查示冠脉主干、左前降支、左回旋支、右冠动脉的检出准确率为别为98.19%、97.50%、97.73%、96.77%;对于冠脉主干、左前降支、左回旋支和右冠动脉病变部位,CTA和CAG检查方法的检出率没有显著差异(Fisher精确检验,P均>0.05)。CTA检查示轻度狭窄、中度狭窄、重度狭窄、闭塞的检出准确率为别为95.92%、96.55%、98.25%、100.00%。对于轻度狭窄、中度狭窄、重度狭窄和闭塞,CTA和CAG检查方法的检出率没有显著差异(P均>0.05),结论CTA在冠心病的诊断中具有较高灵敏度、特异度和准确性,可准确定位冠状动脉病变的分布,精准评估冠脉的狭窄程度,CTA和CAG检查方法具有相似的诊断效能。

Different therapeutic proportion of patients undergone coronary angiography in the era of development in MSCT

Objective To study the different therapeutic proportion of the patient populations undergone coronary angiography(CAG)in the era of development in multislice spiral computed tomography(MSCT).Methods Two hundred and fifty four consecutive patients(mean age 59.24±10.65),who underwent CAG at Daxing Hospital from February 2007 through October 2007,were enrolled,160 patients were male and 94 were female.By evaluating from the coronary angiogram,the patients were not diagnosed to have coronary heart disease(CHD)with less than 50%diameter stenosis of coronary artery;the patients to have CHD with more than or equal to 50%stenosis of coronary artery;the patients were performed the procedure of percutaneous coronary intervention(PCI)with more than or equal to 70%stenosis;the patients were proposed to have coronary aortic bypass graft(CABG)surgery with left main coronary artery lesions or diffuse triple coronary artery lesions.Results In the 254 consecutive patients,59 patients(23.2%)had not been diagnosed to have CHD;195(76.8%)to have CHD,of these patients with CHD,49 patients(19.3%)were not indicated for PCI(including the patients receiving follow-up coronary angiography after stenting),81(31.9%)had been performed the procedure of stent implantation,57(22.4%)proposed to have CABG,8(3.1%)the procedure of PCI had not been successful,or had not been performed because of patients opposing to this therapy.Conclusion Multislice spiral computed tomography can be applied as a non-invasive screening tool to exclude the presence of CHD,to increase the positive proportion of the populations with CHD in all patients receiving coronary angiograhpy,to avoid the use of CAG in a subset of patients.

全模型迭代算法在低剂量头颈CT血管成像中的优势

目的探讨320排宽体探测器CT全模型迭代重建算法(FIRST)与混合迭代重建算法(AIDR 3D)在头颈部CT血管成像(CTA)扫描中对辐射剂量和图像质量的影响。资料与方法收集2021年8—11月于北京医院放射科因头颈部血管疾病接受头颈动脉CTA检查患者70例,采用随机数字表法平均分为A、B组,每组35例。A、B组分别使用AIDR 3D算法和FIRST算法进行重建。比较两组图像头颈部主要血管(主动脉弓、颈总动脉、椎动脉、颈内动脉、大脑中动脉、大脑前动脉)、背景(肌肉、脑组织)的平均CT值、噪声值、信噪比、血管对比噪声比及辐射剂量。由2名医师以5分法对图像质量进行主观评分。结果B组有效辐射剂量显著低于A组[(0.56±0.02)m Sv比(0.78±0.03)m Sv,P<0.001],B组较A组辐射剂量降低28%。B组各血管CT值、信噪比和对比噪声比均显著高于A组(P<0.001),噪声值显著低于A组(P<0.001)。B组背景(胸锁乳突肌、脑组织)CT值、噪声值显著低于A组(P<0.001),信噪比高于A组(P<0.001)。A、B组图像主观评分差异无统计学意义(P>0.05),B组图像诊断医师接受度更高。结论在头颈部CTA扫描中,应用FIRST算法较常规AIDR 3D算法可以降低28%的辐射剂量,并获得更好的图像质量。

优化临界心率采集方案对320排CT冠状动脉成像图像质量和辐射剂量的影响

目的:探讨优化临界心率采集方案对320排CT冠状动脉成像图像质量和辐射剂量的影响.方法:前瞻性收集2019年11月至2022年9月60例(呼吸训练屏气时平均心率为75-79次/min区间)行冠状动脉CT检查者,其中通过手动修改优化为1个心动周期采集者为A组(n=30),通过系统自动设置方案2个心动周期采集者为B组(n=30).记录扫描前平静呼吸时心率(静息心率)、呼吸训练屏气时心率(基础心率)、注射对比剂扫描中的心率(注射时心率)、图像质量和辐射剂量指标进行统计学分析.结果:A组、B组静息心率分别为(78.3±3.9)次/min、(79.1±3.7)次/min,基础心率分别为(76.8±2.7)次/min、(77.3±2.9)次/min,注射时心率分别为(73.8±3.0)次/min、(74.4±2.5)次/min.注射时心率<基础心率<静息心率,A组注射时心率比基础心率平均下降约(3.0±0.7)次/min,B组平均下降约(2.9±0.2)次/min.A组、B组辐射剂量分别为(1.36±0.46)mSv、(2.79±0.52)mSv,差异有统计学意义(t=-2.961,P<0.05).结论:静脉注射对比剂扫描时心率会有所下降,以此为基础调整优化的临界心率采集方案,可在保证图像质量的同时有效降低辐射剂量,使更多受检者获益,值得推广.

双层探测器光谱CT虚拟平扫联合40 keV虚拟单能量成像用于降低小肠CT造影辐射剂量

目的观察双层探测器光谱CT(DLCT)虚拟平扫(VNC)联合40 keV虚拟单能量成像(VMI)用于降低小肠CT造影(CTE)辐射剂量的价值。方法回顾性分析63例接受CT真实平扫(TNC)及双期增强扫描的炎性肠病(IBD)患者,测算病变/组织结构在重建TNC,常规动、静脉期,虚拟动、静脉期平扫(VNC a、VNC v)及40 keV VMI图像中的CT值和图像噪声(SD)、信噪比(SNR)、对比度噪声比(CNR),以及剂量长度乘积(DLP)、容积CT剂量指数(CTDIvol)及有效剂量(ED);对比TNC及VNC图像、常规动脉期及40 keV VMI图像并进行客观评价;对常规扫描与VNC v联合40 keV VMI CTE图像进行主观评价,并比较其辐射剂量。结果TNC、VNC a及VNC v图像中,病变累积肠壁、未累及肠壁及腰大肌CT值差异均无统计学意义(P均>0.05)。病变肠壁、腹主动脉及回结肠静脉在40 keV VMI图像中的CT值、SNR及CNR均高于常规动脉期图像(P均<0.05)。常规扫描与VNC v联合40 keV VM CTE图像主观评分分别为4(4,5)及4(4,5)分,差异无统计学意义(P>0.05)。相比常规扫描方案,VNC v联合40 keV VMI可使CTE辐射剂量下降约67.53%。结论以DLCT VNC联合40 keV VMI可降低CTE辐射剂量。

Sn100 kV在儿童副鼻窦CT检查中的应用

目的探讨Sn100 kV在儿童副鼻窦病变的应用,保证诊断效果的同时减少辐射剂量,提高儿童诊断安全性。方法回顾性分析山西省儿童医院2021年12月至2022年2月100例接受CT检查的副鼻窦病变患儿,采用Sn100 kV扫描、常规CT扫描各50例,比较2组图像质量、辐射剂量。2名医师采用Likert 5级量表对图像质量评分,计算其一致性。结果Sn100 kV组容积CT剂量指数(CTDIvol)为0.52 mGy,剂量-长度乘积(DLP)为(7.4±0.6)mGy·cm,有效直径(ED)为(0.03±0.01)mSv,体型特异性剂量评估(SSDE)为(0.55±0.02)mGy,低于常规CT组(2.6±0.4)mGy,(32.9±7.8)mGy·cm,(0.13±0.04)mSv,(2.68±0.26)mGy,分别降低了79.8%,77.5%,76.9%,79.5%,差异有统计学意义(P<0.001)。骨窗、软窗眶内脂肪和玻璃体信号与干扰加噪声比(SNR)差异均有统计学意义(P<0.001),但仍满足诊断要求。2名医师间图像质量一致性为83.8%。结论Sn100 kV扫描在不影响临床诊断的情况下,可以有效降低辐射剂量。

88岁以上急性肺动脉血栓栓塞症患者误诊分析及文献复习

目的 探讨88岁以上急性肺动脉血栓栓塞症(APTE)患者的临床特点及误诊原因、防范措施。方法 对2020年1月—2023年5月收治的88岁以上APTE 4例的临床资料进行回顾性分析。结果 本组4例均有冠心病,有高血压病3例,糖尿病和心房颤动各2例,慢性阻塞性肺疾病1例。出现胸闷、气短和咳嗽、咳痰各4例,胸痛、晕厥和发热各1例。轻度低氧血症1例,中度低氧血症3例,Ⅰ型呼吸衰竭3例。心电图检查心房颤动、ST-T改变和T波倒置各2例,一度房室传导阻滞1例。肺动脉CT血管造影(CTA)检查均提示双侧多发肺栓塞。曾误诊为肺炎2例,冠心病1例,呼吸衰竭1例。误诊时间2~15 d。4例均经肺动脉CTA检查确诊,均给予抗凝治疗7~10 d好转出院。3例出院后随访3个月治愈,1例正在随访中。结论 88岁以上APTE患者误诊主要原因为基础疾病多、心肺功能差,掩盖了急性肺栓塞引发的临床症状。临床上对于有手术、创伤、恶性肿瘤及心、肺、脑慢性疾病的88岁以上患者应常规进行深静脉栓塞筛查,必要时进行肺栓塞排查。