Application Research of Medical Imaging Practical Teaching Based on Virtual Simulation Teaching Platform

Objective:To explore the application effect of virtual simulation teaching platform in the practical teaching of medical imaging.Methods:A total of 97 students majoring in medical imaging technology of class 2022 were selected and divided into two groups according to the random number method:control group(n=48)and observation group(n=49).The observation group was under the practical teaching mode based on the virtual simulation teaching platform,while the control group was under the traditional multimedia teaching mode.Questionnaire survey and teaching assessment were carried out after the teaching period,and the application effects of the two teaching modes were compared.Results:The reading and theoretical scores of the students in the observation group were significantly higher than those of the students in the control group(P<0.01);there were statistically significant differences in the results of the questionnaire survey(improved learning interest,improved language expression,improved ability to comprehensively analyze problems,and improved teamwork awareness)between the two groups of students(P<0.05);the students in the observation group were markedly more satisfied with the teaching content,teaching methods,and teaching quality than the students in the control group(P<0.05).Conclusion:The medical imaging practical teaching mode based on virtual simulation platform not only helps improve students’theoretical understanding and practical ability in medical imaging technology,but also improves students’learning interest,language expression ability,ability to comprehensively analyze problems,communication skills,teamwork awareness,and satisfaction with the teaching content,teaching methods,and teaching quality.Therefore,it has wide application value in medical specialty education.

Epileptic brain network mechanisms and neuroimaging techniques for the brain network

Epilepsy can be defined as a dysfunction of the brain network,and each type of epilepsy involves different brain-network changes that are implicated diffe rently in the control and propagation of interictal or ictal discharges.Gaining more detailed information on brain network alterations can help us to further understand the mechanisms of epilepsy and pave the way for brain network-based precise therapeutic approaches in clinical practice.An increasing number of advanced neuroimaging techniques and electrophysiological techniques such as diffusion tensor imaging-based fiber tra ctography,diffusion kurtosis imaging-based fiber tractography,fiber ball imagingbased tra ctography,electroencephalography,functional magnetic resonance imaging,magnetoencephalography,positron emission tomography,molecular imaging,and functional ultrasound imaging have been extensively used to delineate epileptic networks.In this review,we summarize the relevant neuroimaging and neuroelectrophysiological techniques for assessing structural and functional brain networks in patients with epilepsy,and extensively analyze the imaging mechanisms,advantages,limitations,and clinical application ranges of each technique.A greater focus on emerging advanced technologies,new data analysis software,a combination of multiple techniques,and the construction of personalized virtual epilepsy models can provide a theoretical basis to better understand the brain network mechanisms of epilepsy and make surgical decisions.

Semi-reference image quality metric for virtual view images in free-viewpoint television

A semi-reference image quality assessment metric based on similarity measurement for synthesizedvirtual viewpoint image (WI) in free-viewpoint television system (FTV) is proposed in this paper. Thekey point of the proposed metric is taking resemblant information between WI and its neighbor view imagesfor quality assessment to make our metric to be extended to multi-semi-reference image quality assessmenteasily. The proposed metric first extracts impact factors from image features, then combines animage synthesis technique and similarity functions, in which, disparity information are taken into accountfor registering the resemblant regions. Experiments are divided into three phases. Phase Ⅰ is to verify thevalidation of the proposed metric by taking impaired images and original reference into account. The experimentalresults show the agreement between evaluation scores and bio-characteristic of human visualsystem. Phase Ⅱ shows the accordance with Phase Ⅰ by taking neighbor view as reference. The proposedmetric can be taken as a full reference one to evaluate the image quality even though the original referenceis absent. Phase Ⅲ is then performed to evaluate the quality of ⅤⅥ. Evaluation scores in the experimentalresults are able to evaluate the quality of ⅤⅥ.

Characterization for elastic constants of fused deposition modelling-fabricated materials based on the virtual fields method and digital image correlation

Fused deposition modelling(FDM), a widely used rapid prototyping process, is a promising technique in manufacturing engineering. In this work, a method for characterizing elastic constants of FDM-fabricated materials is proposed. First of all, according to the manufacturing process of FDM, orthotropic constitutive model is used to describe the mechanical behavior. Then the virtual fields method(VFM) is applied to characterize all the mechanical parameters(Q_(11), Q_(22), Q_(12), Q_(66)) using the full-field strain,which is measured by digital image correlation(DIC). Since the principal axis of the FDM-fabricated structure is sometimes unknown due to the complexity of the manufacturing process, a disk in diametrical compression is used as the load configuration so that the loading angle can be changed conveniently. To verify the feasibility of the proposed method, finite element method(FEM) simulation is conducted to obtain the strain field of the disk. The simulation results show that higher accuracy can be achieved when the loading angle is close to 30?. Finally, a disk fabricated by FDM was used for the experiment. By rotating the disk, several tests with different loading angles were conducted. To determine the position of the principal axis in each test, two groups of parameters(Q_(11), Q_(22), Q_(12), Q_(66)) are calculated by two different groups of virtual fields. Then the corresponding loading angle can be determined by minimizing the deviation between two groups of the parameters. After that, the four constants(Q_(11), Q_(22), Q_(12), Q_(66)) were determined from the test with an angle of 27?.

Adaptive Virtual Source Imaging Using the Sequence Intensity Factor:Simulation and Experimental Study

Virtual source(VS)imaging has been proposed to improve image resolution in medical ultrasound imaging.However,VS obtains a limited contrast due to the non-adaptive delay-and-sum(DAS)beamforming.To improve the image contrast and provide an enhanced resolution,adaptive weighting algorithms were applied in VS imaging.In this paper,we proposed an adjustable generalized coherence factor(aGCF)for the synthetic aperture sequential beamforming(SASB)ofVS imaging to improve image quality.The value of aGCF is adjusted by a sequence intensity factor(SIF)that is defined as the ratio between the effective low resolution scan lines(LRLs)intensity and total LRLs strength.The aGCF-weighted VS(aGCF-VS)images were compared with standard VS images and GCF-weighted VS(GCF-VS)images.Simulation and experimental results demonstrated that the contrast ratio(CR)and contrastto-noise ratio(CNR)of aGCF-VS are greatly improved,compared with standard VS imaging.And in comparison with GCF-VS,aGCF-VS can obtain better CNR and speckle signal-to-noise ratio(sSNR)whilemaintaining similar CR.Therefore,aGCF is suitable for VS imaging to improve contrast and preserve speckle pattern.

Significance of an Advanced Image-Based Virtual Monoenergetic Reconstruction of Dual Source Dual-Energy CT Data at Low keV Increases Image Quality for Portal Vein System of Pancreatic Cancer Patients

Purpose: To explore the significance of dual-source computed tomography (DECT) virtual monoenergetic reconstructions technology in improving image quality for portal vein system of pancreatic cancer patients. Materials and methods: 47 patients with clinically suspected pancreatic cancer (all confirmed by pathology) were collected. Routine plain scan was performed with Siemens Force dual-source dual-energy CT followed by 3 scans respectively carried out in arterial phase, portal phase and delayed phase. Traditional virtual monoenergetic reconstructions (Mono_E) and new generation of virtual monoenergetic reconstructions (Mono+) were respectively performed on portal vein images to obtain virtual single energy images including Mono_ E70 keV, Mono_E 55 keV and Mono+ 70 keV and Mono+ 55 keV. The signal-to-noise ratio (SNR) and noise of portal vein, normal pancreatic tissues and pancreatic lesions of 100 kV, Mono_E and Mono+ images were compared. In addition, the contrast noise ratio of portal vein and lesions as well as pancreatic tissues and lesions (CNR PV, CNRtumor) were also compared. At the same time, two imaging physicians with rich clinical experiences read the films and scored the images of each group by using the 5-point scoring method. Results: Mono+ 55 keV images including SNRpv, SNRpanc, SNRtumor, Noise, CNRpv, CNRtumor were statistically different from 100 KV images and Mono_E images (P < 0.05). As for the subjective score, Mono+ 55 keV image score also had the highest score, which had statistical significance (P < 0.05). The results showed that Mono+ 55 keV images had the best quality. Conclusion: The new generation of virtual Mono+ post-treatment can reduce image noise. Low energy Mono+ images can improve the contrast between pancreatic cancer lesions and portal of pancreatic cancer patients.

Can preoperative planning using IRIS™three-dimensional anatomical virtual models predict operative findings during robot-assisted partial nephrectomy?

Objective To evaluate the predictive validity of IRIS™(Intuitive Surgical®,Sunnyvale,CA,USA)as a planning tool for robot-assisted partial nephrectomy(RAPN)by assessing the degree of overlap with intraoperative execution.Methods Thirty-one patients scheduled for RAPN by four experienced urologists were enrolled in a prospective study.Prior to surgery,urologists reviewed the IRIS™three-dimensional model on an iphone Operating System(iOS)app and completed a questionnaire outlining their surgical plan including surgical approach,and ischemia technique as well as confidence in executing this plan.Postoperatively,questionnaires assessing the procedural approach,clinical utility,efficiency,and effectiveness of IRIS™were completed.The degree of overlap between the preoperative and intraoperative questionnaires and between the planned approach and actual execution of the procedure was analyzed.Questionnaires were answered on a 5-point Likert scale and scores of 4 or greater were considered positive.Results Mean age was 65.1 years with a mean tumor size of 27.7 mm(interquartile range 17.5-44.0 mm).Hilar tumors consisted of 32.3%;48.4%of patients had R.E.N.A.L.nephrometry scores of 7-9.On preoperative questionnaires,the surgeons reported that in 67.7%cases they were confident that they can perform the procedure successfully,and on intraoperative questionnaires,the surgeons reported that in 96.8%cases IRIS™helped achieve good spatial sensation of the anatomy.There was a high degree of overlap between preoperative and intraoperative questionnaires for the surgical approach,interpreting anatomical details and clinical utility.When comparing plans for selective or off-clamp,the preoperative plan was executed in 90.0%of cases intraoperatively.Conclusion A high degree of overlap between the preoperative surgical approach and intraoperative RAPN execution was found using IRIS™.This is the first study to evaluate the predictive accuracy of IRIS™during RAPN by comparing preoperative plan and intraoperative execution.

A modeling method for virtual scene based on multi-view image sequence

Through the analysis and comparison of shortcomings and advantages of existing technologies on object modeling in 3D applications,we propose a new modeling method for virtual scene based on multi-view image sequence to model irregular objects efficiently in 3D application.In 3D scene,this method can get better visual effect by tracking the viewer's real-time perspective position and projecting the photos from different perspectives dynamically.The philosophy of design,the steps of development and some other relevant topics are discussed in details,and the validity of the algorithm is analyzed.The results demonstrate that this method represents more superiority on simulating irregular objects by applying it to the modeling of virtual museum.

Experiment Combined with Picture Archiving and Communication System in the Practical Teaching of Medical Imaging

Objective:To explore the application effect of virtual simulation experiment combined with picture archiving and communication system(PACS)in medical imaging practical teaching.Methods:97 students from the medical imaging class of 2022 were divided into two groups;the control group(n=48)was taught by the traditional teaching method,whereas the research group was taught by virtual simulation experiment combined with PACS(n=49).The teaching achievements and teaching effects of the two groups were compared to define the advantages of the two teaching modes.Results:Initially,there were no significant differences in the basic theory,image analysis,report writing,and differential diagnosis scores between the two groups of students(P>0.05);however,after 16 weeks of teaching,the scores of the research group were better than those of the control group(P<0.05);the pass rate of students in the study group(93.88%)was higher than that in the control group(81.25%);the scores of students in the research group in terms of clinical inquiry skills,X-ray/computed tomography/magnetic resonance imaging(X-ray/CT/MRI)operation skills,and doctor-patient communication skills were significantly higher than those in the control group(P<0.05).Conclusion:In medical imaging practical teaching,the application of virtual simulation experiment combined with PACS can effectively address several problems in the traditional teaching mode,including the single teaching method,the single teaching content,and the lack of innovation,and,at the same time,improve students’basic theoretical knowledge,X-ray/CT/MRI operation skills,consultation skills,and doctor-patient communication skills,thereby effectively improving the teaching quality and learning effect.

双能量CT非线性融合和噪声优化的虚拟单能量图像技术在喉鳞状细胞癌中的应用

目的:探讨双能量CT线性融合图像(linear blending imaging,LBI)、非线性融合图像(nonlinear blending image,NBI)和噪声优化的虚拟单能量图像(noise-optimized virtual monoenergetic image,VMI+)技术在喉鳞状细胞癌中的应用价值。方法:回顾性分析2019年6月至2022年3月61例经病理证实为喉鳞状细胞癌患者的双能量CT资料。双能量图像采用LBI[融合系数为1(80 kV)和0.6(M0.6)]、NBI和VMI+(40 keV、55 keV)技术重建。比较5组图像的客观图像质量[对比噪声比(contrast-tonoise ratio,CNR)、肿瘤CT值、噪声]和主观图像质量(肿瘤边界评分和整体图像质量评分)。结果:40 keV的CNR、肿瘤CT值和肿瘤边界评分均明显高于80 kV、M0.6、NBI和55 keV,差异均有统计学意义(均P<0.05)。NBI的整体图像质量评分明显高于80 kV、M0.6、40 keV和55 keV,差异均有统计学意义(均P<0.05)。NBI的噪声明显低于80 kV、40 keV和55 keV,差异均有统计学意义(均P<0.05)。结论:在喉鳞状细胞癌的双能量CT中,采用VMI+技术(40 keV)能提供更好的CNR、肿瘤CT值和肿瘤边界,采用NBI技术能提供更低的噪声和更好的整体图像质量。

数字图像处理及应用虚拟仿真实验平台设计

针对数字图像处理及应用实验教学的需要,结合当下图像处理技术的热点应用,利用虚拟仿真技术、交互操作等信息化手段进行实验教学,设计并开发了数字图像处理及应用虚拟仿真实验教学平台。实验教学平台包含交通标志数字图像处理、图像分类、图像识别、视频处理、自动驾驶应用等5个虚拟仿真实验教学资源,共13个交互实验步骤。该平台特色显著、虚实结合,达到了良好的教学效果,为“新工科”背景下的虚拟仿真实验教学提供有益的参考。

基于虚拟样本伪标签生成的高光谱图像分类

半监督高光谱图像分类的精度一般随着标记像素数的增加而提高.然而,标签样本的获得费时费力,且依赖于专家知识.针对这个问题,提出了一种通过少量标签样本生成具有伪标签的虚拟样本新方法.基于数学中的凸集理论,所提出的方法利用少量的训练样本可以生成任意多的带有伪标签的虚拟样本,有效地扩大了训练样本集,明显改善了半监督分类器的分类结果.为了验证所提方法的有效性,在Indian Pines和Pavia University两个常用的实际高光谱数据集上进行了广泛测试.实验结果表明,利用所提出的方法在分类具有少量标签样本的高光谱图像时,3个评价分类结果的指标值均有明显提升.

3种方法单独及联合诊断甲状腺微小结节的价值比较

目的 比较二维高频超声、声脉冲辐射力成像(ARFI)-声触诊组织定量(VTQ)技术及应变弹性成像3种方法单独及联合诊断甲状腺微小结节良恶性的价值。方法 回顾性分析2021年6月—2023年6月在陕西省宝鸡市人民医院就诊的99例(107个甲状腺微小实性结节)结节直径≤10.0 mm患者的临床资料,均采用二维高频超声、ARF-VTQ技术及应变弹性成像进行检查,获得超声资料评分及数据,以穿刺活检和手术病理结果为诊断“金标准”,比较3种超声检查方法单独及联合应用对甲状腺微小结节的诊断效能。结果 62例患者(共68个结节)选择FNAB,37例患者(共39个结节)选择手术。107个甲状腺微小结节中,诊断为恶性微小结节45个,良性微小结节62个。恶性微小结节与良性微小结节相比,结节内回声(等回声和高回声、极低回声和低回声)、边界、微钙化、纵横比>1及血供情况和供血动脉阻力指数(RI)比较,差异均有统计学意义(P<0.05)。二维高频超声诊断甲状腺微小结节C-TIRADS积分临界值≥2分(C-TIRADS 4b)时,诊断灵敏度为73.33%,特异度为79.03%,曲线下面积[AUC(95%CI)]为0.762(95%CI:0.670~0.839);ARFI-VTQ技术中,107个甲状腺微小结节SWV测值为0.52~7.55 m/s,平均(2.62±0.61)m/s,其中24个实性结节多次出现×.××m/s,最后测值以7.55 m/s记录。恶性微小结节SWV均值为(5.24±2.23) m/s,高于良性微小结节的(2.11±0.70) m/s,差异有统计学意义(t=10.258,P<0.05);当SWV临界值为3.19 m/s时,诊断灵敏度为77.78%,特异度为80.65%,AUC(95%CI)为0.792(95%CI:0.703~0.865);应变弹性成像检查中,当评分临界值≥3分时,诊断的灵敏度为75.56%,特异度为77.42%,AUC(95%CI)为0.765(95%CI:0.673~0.841)。三者联合应用诊断的阳性微小结节为44个,阴性微小结节63个,诊断灵敏度为93.33%,特异度为96.77%,AUC(95%CI)为0.951(95%CI:0.891~0.983)。三者联合诊断效能与二维高频超声检查、ARFI-VTQ、应变弹性成像单独检测比较,差异均有统计学意义(Z=4.861、4.393、4.842,P<0.05)。结论 二维高频超声联合ARFI-VTQ技术及应变弹性成像可提高甲状腺微小结节良恶性的诊断准确性。

塞曼效应实验之虚拟仿真与电脑辅助对比分析

塞曼效应实验通过测量汞绿光在磁场中分裂谱线的波长差计算电子的荷质比。电脑辅助版塞曼效应实验利用CCD图像采集卡将法布里-珀罗标准具等倾干涉图像采集到电脑,再利用塞曼效应实验分析软件对图像进行处理,测出光分裂的谱线波长差,计算出电子荷质比。虚拟仿真型塞曼效应实验则是利用科大奥锐提供的虚拟仿真实验系统,从实验仪器的摆放、调试到测量及数据处理,实现对塞曼效应实验的全程模拟仿真。电脑辅助版塞曼效应实验克服了过去手工测量的诸多缺陷,但并没有解决所有不足,还带来一些新问题。塞曼效应虚拟仿真实验几乎解决了传统塞曼效应实验所遇到的所有问题,只要必要的步骤操作到位,就可以得到理想的实验结果。通过研究分析,深刻认识到两种实验方式相互不能完全替代,但可以作为有益补充。

乳腺癌患者HER2、CA153表达与声触诊组织成像定量技术参数的相关性分析

目的:分析乳腺癌患者人表皮生长因子受体2(HER2)、糖类抗原153(CA153)表达与声触诊组织成像定量(VTIQ)技术参数的相关性。方法:选取2018年5月至2020年5月合肥市第三人民医院收治的80例女性乳腺癌患者,其中世界卫生组织(WHO)分期Ⅰ期14例、Ⅱ期22例、Ⅲ期31例、Ⅳ期13例;另选取同时间段收治的53例女性乳腺良性疾病患者为对照。所有患者先行常规超声检查,随后进入超声VTIQ成像模式获得剪切波速度(SWV)均值参数;采用免疫组织化学法检测乳腺组织中HER2表达,采用罗氏E411电化学发光免疫分析仪检测血清CA153水平;采用Pearson法分析乳腺癌患者血清CA153水平与SWV均值的相关性。结果:与良性患者比较,乳腺癌患者VTIQ技术参数SWV均值、血清CA153水平及HRR2阳性表达率均显著升高,差异有统计学意义(F=39.107,78.353,P<0.05);与乳腺癌Ⅰ+Ⅱ期患者比较,乳腺癌Ⅲ、Ⅳ期患者VTIQ技术参数SWV均值、血清CA153水平、HRR2阳性表达率均显著升高,差异有统计学意义(t=2.685、3.556、8.326、10.455,P<0.05);与乳腺癌Ⅲ期比较,乳腺癌Ⅳ期患者VTIQ技术参数SWV均值、血清CA153水平、HRR2阳性表达率均显著升高,差异有统计学意义(t=4.632、8.659,P<0.05)。与HER2阴性表达乳腺癌患者SWV均值比较,HER2阳性表达乳腺癌患者SWV均值升高,差异有统计学意义(χ^(2)=59.751,P<0.05)。乳腺癌患者血清CA153水平与SWV均值呈正相关(r=0.501,P<0.05)。结论:乳腺癌患者VTIQ参数SWV均值与乳腺癌患者生物标志物HER2、CA153表达水平密切相关。

新媒体环境下广州市音乐文化产业发展现状

新媒体环境下,广州市音乐文化产业呈现出自媒体营销模式和高科技应用模式的特点。自媒体营销模式包括宣传模式、销售模式和内容制作模式,具有交互性强、传播迅速、突破时空限制等特点。高科技应用模式包括流媒体模式、虚拟影像模式和人工智能模式。人工智能模式的“AI算法”使音乐作品的创作效率提高,并符合市场需求。虚拟影像技术丰富了舞台美学设计,创新了线上音乐演出活动的形式和内容。流媒体应用工具功能更具综合性,使用更方便更人性化。该文通过对新媒体环境下广州市音乐文化产业发展现状进行分析,以期保障广州音乐文化产业的多元和创新发展。

光谱CT显示左结肠动脉的最佳虚拟单能量

目的:探讨双层探测器光谱CT显示左结肠动脉(LCA)的最佳虚拟单能量,旨在为腹腔镜直肠癌根治术前评估LCA提供帮助。方法:回顾性分析在本院行腹部CT血管成像(CTA)扫描的100例患者的影像学资料,将动脉期原始图像重组成混合能量图像以及基于能谱的间隔10 keV的40~70 keV的单能量图像。对5组图像LCA的CT值、信噪比(SNR)、对比噪声比(CNR)、图像噪声以及图像质量评分进行比较。结果:40~70 keV组单能量图像LCA的CT值、噪声、CNR、SNR随着能级的升高呈递减趋势。常规混合能量图像组及40~70 keV单能量图像组两两比较,各组间CT值、SNR、CNR、噪声差异有统计学意义(P<0.05)。40 keV组图像LCA的CT值、CNR、SNR均高于其他组,噪声低于常规混合能量图像组。两名影像科医师图像质量主观评价的一致性良好(0.40≤Kappa值<0.75),各组间图像主观评分差异均有统计学意义(P均<0.001)。40 keV组图像主观评分最高,40~70 keV组单能量图像质量均高于常规混合能量图像。结论:40 keV为显示LCA的最佳虚拟单能量,显示血管清晰、边缘锐利,能更清晰显示LCA及其解剖变异,利于外科医生腹腔镜直肠癌根治术的顺利进行。

新一代帕洛马天文台光谱仪的虚拟刀口欠采样像质测量方法

天文光谱仪的成像质量可用点扩散函数或线扩散函数来表征,但其相对于光谱仪探测器通常为欠采样,很难直接测量。在新一代帕洛马天文台光谱仪的像质测试中引入虚拟刀口法进行光源物面扫描,并应用虚拟刀口法开展欠采样光谱仪像质及光源尺度测量,通过模拟和实验研究,对比分析过采样经典直边刀口法和过采样直接测量方法,验证了虚拟刀口法具有良好的测量精度。在693 nm处,直边刀口法测得光谱仪过采样线扩散函数的半高全宽为7.05μm,虚拟刀口法测量欠采样线扩散函数的半高全宽为7.14μm,测量误差为1.3%。在0.3"视场的光源尺度下,虚拟刀口法测得689、693、701 nm欠采样线扩散函数的半高全宽分别为24.2、27.7、30.8μm,以过采样直接测量结果为参考,其测量准确度分别为98.3%,93.9%和88.8%。实验结果表明,探测器成像严重欠采样时,采用光源物面扫描的虚拟刀口法可准确测量光谱仪的成像质量,该方法结合色散系数还可实现光谱仪分辨率的测量,相关研究工作可为天文光谱仪像质的直接测量提供借鉴。

电子游戏中图书馆虚拟形象分析

近半个世纪以来,电子游戏已经成为社会文化环境的重要组成部分,研究电子游戏中图书馆的虚拟形象,有助于全面了解公众对图书馆的整体印象,对图书馆的生存发展态势做出合理预测。同时,游戏被认为是最接近元宇宙的领域,通过探析游戏中图书馆的形态与功能,有助于了解图书馆在元宇宙中可能扮演的角色。文章重点分析了游戏中图书馆的虚拟建筑形象、虚拟资源形象、虚拟服务形象和虚拟馆员形象,发现图书馆是游戏中常见的社会机构,已成为虚拟世界里的一种文化象征。信息资源存储与传承、场景化的虚拟服务是游戏中图书馆的主要功能,同时,在游戏中,图书馆开启了实体空间虚拟化的序幕,部分已呈现出元宇宙图书馆的初始形态。

双能CT虚拟单能联合迭代重建技术对门静脉精准成像

目的:探索双源双能CT虚拟单能技术联合迭代重建提高门静脉成像质量的价值。方法:本研究前瞻性纳入30例患者,所有患者均采用双能量门静脉增强扫描,结合不同迭代强度(1、3、5级)进行数据重建,再对三组迭代重建数据分别进行虚拟单能量成像(40KeV、60KeV、80KeV、100KeV、120KeV、140keV)和传统120KeV混合能成像,最终每位患者获得21组图像。然后由2位放射科医生独立测量每组图像感兴趣区的平均CT值、噪声、信噪比(SNR)、对比噪声比(CNR),还对每组图像质量进行主观评分。采用组内相关系数(Intraclass correlation coefficient, ICC)对两组独立测量数据进行一致性评价,而各指标组间比较采用方差分析。结果:两位放射科医生测量的门脉主干CT值、CNR、图像噪声及主观评分一致性极好,其ICC分别为0.95、0.93、0.87、0.80。各图像质量客观指标在不同迭代强度和单能组合的组内比较均有显著统计学差异(P<0.001)。40KeV单能图像的门脉主干CT值均明显高于其他单能图像(P<0.001)。在同一迭代模式下40KeV单能图像的CNR亦明显高于其他单能图像(P<0.001),且主观评分也显著升高P<0.05,其中A3-40KeV单能图像主观评分最高。结论:与120KeV传统成像技术相比,ADMIRE 3迭代强度联合40KeV单能重建能在控制噪声的同时大幅提升门静脉CNR,从而实现门静脉的精准成像。