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Markov Chain Monte Carlo-Based L1/L2 Regularization and Its Applications in Low-Dose CT Denoising
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作者 Shuoqi Yu 《Journal of Applied Mathematics and Physics》 2025年第2期419-428,共10页
In this paper, a low-dose CT denoising method based on L1/L2regularization method of Markov chain Monte Carlo is studied. Firstly, the mathematical model and regularization method of low-dose CT denoising are summariz... In this paper, a low-dose CT denoising method based on L1/L2regularization method of Markov chain Monte Carlo is studied. Firstly, the mathematical model and regularization method of low-dose CT denoising are summarized, and then the theoretical basis of MCMC method and its application in image denoising are introduced. We evaluated the performance of various regularization strategies by comparing the denoising effects of L1, L2, and L1/L2regularization terms in MCMC sampling at Gaussian noise levels. The experimental results show that L1/L2regularization has the best performance in balancing noise removal and image detail retention, significantly superior to single L1and L2regularization, which proves its effectiveness for low-dose CT denoising. 展开更多
关键词 low-dose ct Denoising REGULARIZATION Statistical Inverse Problem MCMC Sampling
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Low-dose CT image denoising method based on generative adversarial network
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作者 JIAO Fengyuan YANG Zhixiu +1 位作者 SHI Shaojie CAO Weiguo 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第4期490-498,共9页
In order to solve the problems of artifacts and noise in low-dose computed tomography(CT)images in clinical medical diagnosis,an improved image denoising algorithm under the architecture of generative adversarial netw... In order to solve the problems of artifacts and noise in low-dose computed tomography(CT)images in clinical medical diagnosis,an improved image denoising algorithm under the architecture of generative adversarial network(GAN)was proposed.First,a noise model based on style GAN2 was constructed to estimate the real noise distribution,and the noise information similar to the real noise distribution was generated as the experimental noise data set.Then,a network model with encoder-decoder architecture as the core based on GAN idea was constructed,and the network model was trained with the generated noise data set until it reached the optimal value.Finally,the noise and artifacts in low-dose CT images could be removed by inputting low-dose CT images into the denoising network.The experimental results showed that the constructed network model based on GAN architecture improved the utilization rate of noise feature information and the stability of network training,removed image noise and artifacts,and reconstructed image with rich texture and realistic visual effect. 展开更多
关键词 low-dose ct image generative adversarial network noise and artifacts encoder-decoder atrous spatial pyramid pooling(ASPP)
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Hformer:highly efficient vision transformer for low-dose CT denoising 被引量:1
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作者 Shi-Yu Zhang Zhao-Xuan Wang +5 位作者 Hai-Bo Yang Yi-Lun Chen Yang Li Quan Pan Hong-Kai Wang Cheng-Xin Zhao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第4期161-174,共14页
In this paper,we propose Hformer,a novel supervised learning model for low-dose computer tomography(LDCT)denoising.Hformer combines the strengths of convolutional neural networks for local feature extraction and trans... In this paper,we propose Hformer,a novel supervised learning model for low-dose computer tomography(LDCT)denoising.Hformer combines the strengths of convolutional neural networks for local feature extraction and transformer models for global feature capture.The performance of Hformer was verified and evaluated based on the AAPM-Mayo Clinic LDCT Grand Challenge Dataset.Compared with the former representative state-of-the-art(SOTA)model designs under different architectures,Hformer achieved optimal metrics without requiring a large number of learning parameters,with metrics of33.4405 PSNR,8.6956 RMSE,and 0.9163 SSIM.The experiments demonstrated designed Hformer is a SOTA model for noise suppression,structure preservation,and lesion detection. 展开更多
关键词 low-dose ct Deep learning Medical image Image denoising Convolutional neural networks Selfattention Residual network Auto-encoder
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Low-Dose CT Image Denoising Based on Improved WGAN-gp 被引量:3
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作者 Xiaoli Li Chao Ye +1 位作者 Yujia Yan Zhenlong Du 《Journal of New Media》 2019年第2期75-85,共11页
In order to improve the quality of low-dose computational tomography (CT)images, the paper proposes an improved image denoising approach based on WGAN-gpwith Wasserstein distance. For improving the training and the co... In order to improve the quality of low-dose computational tomography (CT)images, the paper proposes an improved image denoising approach based on WGAN-gpwith Wasserstein distance. For improving the training and the convergence efficiency, thegiven method introduces the gradient penalty term to WGAN network. The novelperceptual loss is introduced to make the texture information of the low-dose imagessensitive to the diagnostician eye. The experimental results show that compared with thestate-of-art methods, the time complexity is reduced, and the visual quality of low-doseCT images is significantly improved. 展开更多
关键词 WGAN-gp low-dose ct image image denoising Wasserstein distance
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Low-dose CT coronary angiography using iterative reconstruction with a 256-slice CT scanner 被引量:2
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作者 Patricia Carrascosa Gastón A Rodriguez-Granillo +1 位作者 Carlos Capuay Alejandro Deviggiano 《World Journal of Cardiology》 CAS 2013年第10期382-386,共5页
AIM:To explore whether computer tomography coronary angiography(CTCA) using iterative reconstruction(IR) leads to significant radiation dose reduction without a significant loss in image interpretability compared to c... AIM:To explore whether computer tomography coronary angiography(CTCA) using iterative reconstruction(IR) leads to significant radiation dose reduction without a significant loss in image interpretability compared to conventional filtered back projection(FBP).METHODS:A consecutive series of 200 patients referred to our institution to undergo CTCA constituted the study population.Patients were sequentially assigned to FBP or IR.All studies were acquired with a 256-slice CT scanner.A coronary segment was considered interpretable if image quality was adequate for evaluation of coronary lesions in all segments ≥ 1.5 mm.RESULTS:The mean age was 56.3±9.6 years and165(83%) were male,with no significant differences between groups.Most scans were acquired using prospective ECG triggering,without differences between groups(FBP 84%vs IR 82%;P=0.71).A total of 3198(94%) coronary segments were deemed of diagnostic quality.The percent assessable coronary segments was similar between groups(FBP 91.7%±4.0% vs IR92.5% ± 2.8%; P=0.12).Radiation dose was significantly lower in the IR group(2.8±1.4 mSvvs 4.6±3.0mSv;P<0.0001).Image noise(37.8±1.4 HUvs 38.2±2.4 HU; P=0.20) and signal density(461.7±51.9HU vs 462.2±51.2 HU; P=0.54) levels did not differ between FBP and IR groups,respectively.The IR group was associated to significant effective dose reductions,irrespective of the acquisition mode.CONCLUSION:Application of IR in CTCA preserves image interpretability despite a significant reduction in radiation dose. 展开更多
关键词 low-dose computer TOMOGRAPHY CORONARY ANGIOGRAPHY ITERATIVE reconstruction
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Cost-effectiveness of lung cancer screening by low-dose CT in China:a micro-simulation study 被引量:1
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作者 Yihui Du Yanju Li +9 位作者 Grigory Sidorenkov Rozemarijn Vliegenthart Marjolein A.Heuvelmans Monique D.Dorrius Harry J.M.Groen Shiyuan Liu Li Fan Zhaoxiang Ye Marcel J.W.Greuter Geertruida H.de Bock 《Journal of the National Cancer Center》 2022年第1期18-24,共7页
Background:The effectiveness of lung cancer screening with low-dose computed tomography(LDCT)has been established.The current study evaluates the cost-effectiveness of lung cancer screening with LDCT in a general popu... Background:The effectiveness of lung cancer screening with low-dose computed tomography(LDCT)has been established.The current study evaluates the cost-effectiveness of lung cancer screening with LDCT in a general population in China.Methods:A previously validated micro-simulation model was used to simulate a cohort of men and women on a lifetime horizon in the presence and absence of LDCT screening.The modeling data were collected from numerous national and international sources.Simulated screening scenarios included different combinations of screening intervals and start and stop ages.Additional costs(valued in Chinese Yuan,CNY;1 USD=6.8976 CNY,1 EUR=7.8755 CNY in 2020),life-years gained(LYG)and mortality reduction due to screening were also determined.The costs and life-years were discounted by 3%.All results were scaled to 1,000 individuals.The average cost-effectiveness ratio(ACER)was calculated.A willingness-to-pay threshold of CNY 217.3k/LYG was considered.A healthcare system perspective was adopted.Results:Compared to no screening,lung cancer screening by LDCT in a general Chinese population yielded 21.0-36.7 LYG in men and 9.2-16.6 LYG in women across the scenarios.For men,biennial LDCT screening yielded an ACER of CNY 171.4k-306.3k/LYG relative to no screening.Biennial screening performed between 55 and 75 years of age was optimal at the defined threshold;it resulted in CNY 174.6k/LYG and a lung cancer mortality reduction of 9.1%,and this scenario had a 75%probability of being cost-effective.For women,the ACER ranged from CNY 364.2k to 1193.3k/LYG.Conclusions:In China,lung cancer screening with LDCT in the general population including never smokers could be cost-effective for men with 75%probability,but not for women.The optimal strategy for men would be performing biennial screening between 55 and 75 years of age. 展开更多
关键词 COST-EFFEctIVENESS low-dose computed tomography Lung neoplasm Mass screening Microsimulation model General population
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Body Pushers: Low-Dose CT, Always the Best Choice? A Study of the Diagnostic Performance of CT Scout View
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作者 Robin Fabian Gohmann Frauke Heckner +2 位作者 Diane Uschner Christiane Katharina Kuhl Sebastian Daniel Reinartz 《Open Journal of Radiology》 2017年第2期112-120,共9页
Purpose: The purpose of this study has been to evaluate the diagnostic information contained in the CT scout view in the detection of body packing. Materials and methods: Retrospect analysis of 43 CT scans between Jul... Purpose: The purpose of this study has been to evaluate the diagnostic information contained in the CT scout view in the detection of body packing. Materials and methods: Retrospect analysis of 43 CT scans between July 2011 and June 2013 in asymptomatic suspects of body packing (29 men, 14 females, mean age 38 ± 9 years). Results: A total of 11 positive cases of body packing were identified. In 10 (91%) of the cases packets were relatively large and spares in number (3 or less);in 7 (64%) a single packet has been identified. 6 (55%) of the packets were located rectally, 4 (36%) vaginally and in 1 (9%) case multiple small packets of approximately 1 cm in size were found to have been ingested orally. Maximum and minimum diameters were 5.9 ± 3 cm and 2.9 ± 1.4 cm, respectively. The mean weight of packets was 7.5 ± 4.2 g (range 2 - 54 g). In 73% (n = 8) heroin had been detected;other drugs such as cocaine (n = 1) and cannabis (n = 1) were encountered once, respectively. One packet was identified retrospectively and its content could therefore not be identified. The average effective dose was 3.8 ± 2.1 mSv for CT, of that 0.12 ± 0.01 mSv was required for the CT scout view. Conclusion: If CT scout view were treated as a diagnostic image, some CT scans may be omitted, thereby maintaining streamlined operations and achieving further dose reduction jointly in the workup of body packing. 展开更多
关键词 BODY Packing ct SCOUT VIEW ct Dose Reduction X-Ray
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Malignant glaucoma treated by low-dose laser cycloplasty: a 1-year multicenter prospective noncomparative study 被引量:1
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作者 Hai-Shuang Lin Xiao-Ping Xu +18 位作者 Xuan-Li Zheng Ji-Bing Wang Su-Jie Fan Zuo-HongWu Su-Mian Cheng Li-Jun Zhao Qin-Hua Cai Shao-Dan Zhang Shan-Shan Liu Ai-Guo Lyu Ying Zhang Hong Chen Dan-Ni Jiang Wu-Liang Li Nathan Congdon Clement C Tham Ming-Guang He Yuan-Bo Liang the Malignant Glaucoma TreatmentTrial Study(MGTT)Group 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第7期1248-1254,共7页
AIM:To report a one-year clinical outcomes of low-dose laser cycloplasty(LCP)among malignant glaucoma patients.METHODS:In this prospective,multicenter,noncomparative clinical study,participants with malignant glaucoma... AIM:To report a one-year clinical outcomes of low-dose laser cycloplasty(LCP)among malignant glaucoma patients.METHODS:In this prospective,multicenter,noncomparative clinical study,participants with malignant glaucoma were recruited and underwent LCP at eight ophthalmic centers in China.Patients were followed up at 1wk,1,3,6,and 12mo.Intraocular pressure(IOP),number of glaucoma medications,anterior chamber depth(ACD),and complications were recorded.Anatomical success was defined as the reformation of the anterior chamber based on slit-lamp biomicroscopy.Recurrence was defined by the presence of a shallow orflat anterior chamber after initial recovery from treatment.RESULTS:A total of 34 eyes received LCP.Mean IOP and medications decreased from 36.1±11.5 mm Hg with 3.3±1.5 glaucoma medications pre-treatment to 20.9±9.8 mm Hg(P<0.001)with 2.9±1.6 medications(P=0.046)at 1d,and 17.4±6.7 mm Hg(P<0.001)with 1.3±1.7 medications(P<0.001)at 12mo.The ACD increased from 1.1±0.8 mm at baseline to 1.7±1.0 mm and to 2.0±0.5 mm at 1d and 12mo,respectively.A total of 32(94.1%)eyes achieved initial anatomical success.During follow-up,2(5.9%)eyes failed and 8(23.5%)eyes relapsed,yielding a 12-month anatomical success rate of 64.3%.Complications including anterior synechia(8.82%),choroidal/ciliary detachment(5.88%)and hypopyon(2.94%)were observed within 1wk.CONCLUSION:LCP is simple,safe,and effective in reforming the anterior chamber in malignant glaucoma. 展开更多
关键词 anterior chamber reformation intraocular pressure low-dose laser cycloplasty malignant glaucoma anatomical success
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Efficacy and safety of low-dose cyclophosphamide combined with lenvatinib, pembrolizumab and TACE for unresectable hepatocellular carcinoma:A single-center, prospective,single-arm clinical trial
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作者 Yupeng Ren Yuxuan Li +8 位作者 Mingbo Cao Yongchang Tang Feng Yuan Gaoyuan Yang Zhiwei He Zheng Shi Xiaorui Su Zhicheng Yao Meihai Deng 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第2期114-123,共10页
Objective: Unresectable hepatocellular carcinoma(uHCC) continues to pose effective treatment options. The objective of this study was to assess the efficacy and safety of combining low-dose cyclophosphamide with lenva... Objective: Unresectable hepatocellular carcinoma(uHCC) continues to pose effective treatment options. The objective of this study was to assess the efficacy and safety of combining low-dose cyclophosphamide with lenvatinib, pembrolizumab and transarterial chemoembolization(TACE) for the treatment of uHCC.Methods: From February 2022 to November 2023, a total of 40 patients diagnosed with uHCC were enrolled in this small-dose, single-center, single-arm, prospective study. They received a combined treatment of low-dose cyclophosphamide with lenvatinib, pembrolizumab, and TACE. Study endpoints included progression-free survival(PFS), objective response rate(ORR), and safety assessment. Tumor response was assessed using the modified Response Evaluation Criteria in Solid Tumors(mRECIST), while survival analysis was conducted through KaplanMeier curve analysis for overall survival(OS) and PFS. Adverse events(AEs) were evaluated according to the National Cancer Institute Common Terminology Criteria for Adverse Events(version 5.0).Results: A total of 34 patients were included in the study. The median follow-up duration was 11.2 [95% confidence interval(95% CI), 5.3-14.6] months, and the median PFS(mPFS) was 15.5(95% CI, 5.4-NA) months.Median OS(mOS) was not attained during the study period. The ORR was 55.9%, and the disease control rate(DCR) was 70.6%. AEs were reported in 27(79.4%) patients. The most frequently reported AEs(with an incidence rate >10%) included abnormal liver function(52.9%), abdominal pain(44.1%), abdominal distension and constipation(29.4%), hypertension(20.6%), leukopenia(17.6%), constipation(17.6%), ascites(14.7%), and insomnia(14.7%). Abnormal liver function(14.7%) had the most common grade 3 or higher AEs.Conclusions: A combination of low-dose cyclophosphamide with lenvatinib, pembrolizumab, and TACE is safe and effective for u HCC, showcasing a promising therapeutic strategy for managing uHCC. 展开更多
关键词 Hepatocellular carcinoma lenvatinib low-dose cyclophosphamide pembrolizumab transarterial chemoembolization
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A NONLOCAL KRONECKER-BASIS-REPRESENTATION METHOD FOR LOW-DOSE CT SINOGRAM RECOVERY
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作者 Jian Lu Huaxuan Hu +4 位作者 Yuru Zou Zhaosong Lu Xiaoxia Liu Keke Zu Lin Li 《Journal of Computational Mathematics》 SCIE CSCD 2024年第4期1080-1108,共29页
Low-dose computed tomography(LDCT)contains the mixed noise of Poisson and Gaus-sian,which makes the image reconstruction a challenging task.In order to describe the statistical characteristics of the mixed noise,we ad... Low-dose computed tomography(LDCT)contains the mixed noise of Poisson and Gaus-sian,which makes the image reconstruction a challenging task.In order to describe the statistical characteristics of the mixed noise,we adopt the sinogram preprocessing as a stan-dard maximum a posteriori(MAP).Based on the fact that the sinogram of LDCT has non-local self-similarity property,it exhibits low-rank characteristics.The conventional way of solving the low-rank problem is implemented in matrix forms,and ignores the correlations among similar patch groups.To avoid this issue,we make use of a nonlocal Kronecker-Basis-Representation(KBR)method to depict the low-rank problem.A new denoising model,which consists of the sinogram preprocessing for data fidelity and the nonlocal KBR term,is developed in this work.The proposed denoising model can better illustrate the generative mechanism of the mixed noise and the prior knowledge of the LDCT.Nu-merical results show that the proposed denoising model outperforms the state-of-the-art algorithms in terms of peak-signal-to-noise ratio(PSNR),feature similarity(FSIM),and normalized mean square error(NMSE). 展开更多
关键词 low-dose computed tomography Kronecker-basis-representation Low-rank imation.Noise-generating-mechanism
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Strided Self-Supervised Low-Dose CT Denoising for Lung Nodule Classification 被引量:2
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作者 Yiming Lei Junping Zhang Hongming Shan 《Phenomics》 2021年第6期257-268,共12页
Lung nodule classification based on low-dose computed tomography(LDCT)images has attracted major attention thanks to the reduced radiation dose and its potential for early diagnosis of lung cancer from LDCT-based lung... Lung nodule classification based on low-dose computed tomography(LDCT)images has attracted major attention thanks to the reduced radiation dose and its potential for early diagnosis of lung cancer from LDCT-based lung cancer screening.However,LDCT images suffer from severe noise,largely influencing the performance of lung nodule classification.Current methods combining denoising and classification tasks typically require the corresponding normal-dose CT(NDCT)images as the supervision for the denoising task,which is impractical in the context of clinical diagnosis using LDCT.To jointly train these two tasks in a unified framework without the NDCT images,this paper introduces a novel self-supervised method,termed strided Noise2Neighbors or SN2N,for blind medical image denoising and lung nodule classification,where the supervision is generated from noisy input images.More specifically,the proposed SN2N can construct the supervision infor-mation from its neighbors for LDCT denoising,which does not need NDCT images anymore.The proposed SN2N method enables joint training of LDCT denoising and lung nodule classification tasks by using self-supervised loss for denoising and cross-entropy loss for classification.Extensively experimental results on the Mayo LDCT dataset demonstrate that our SN2N achieves competitive performance compared with the supervised learning methods that have paired NDCT images as supervision.Moreover,our results on the LIDC-IDRI dataset show that the joint training of LDCT denoising and lung nodule classification significantly improves the performance of LDCT-based lung nodule classification. 展开更多
关键词 Convolutional neural network Medical image classification Self-supervised denoising low-dose ct
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基于双源CT的影像学模型对儿童上尿路结石的诊断价值 被引量:1
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作者 唐琴 吴广巍 +4 位作者 孙亮 刘克明 曲源 陈杰 艾尼瓦尔·玉素甫 《中国CT和MRI杂志》 2025年第1期143-146,共4页
目的 探讨基于双源CT(dual-source CT,DSCT)的影像学模型用于儿童上尿路不同成分结石分析的诊断价值。方法 收集2021年1月至2022年12月间上尿路结石的53例患儿作为研究对象。其中体内的结石分析应用双能量方式进行扫描,而体外结石则将... 目的 探讨基于双源CT(dual-source CT,DSCT)的影像学模型用于儿童上尿路不同成分结石分析的诊断价值。方法 收集2021年1月至2022年12月间上尿路结石的53例患儿作为研究对象。其中体内的结石分析应用双能量方式进行扫描,而体外结石则将其放置于新鲜的猪肾内并全部浸于生理盐水中再扫描,体内和体外结石的扫描条件一致。在其软组织窗分别采用80kV、120kV和140kV电压下测定患儿结石的CT值,并采用双能量结石分析的相关软件对其主要成分进行判断。同时应用前期文献构建的影像组学预测模型和红外光谱分析结石样品的主要成分。结果 影像组学预测模型和采用红外光谱法分析发现29例纯结石,5例为混合结石。24例术前采用DSCT扫描发现21例纯结石, 2例混合结石。经统计分析,草酸钙结石、尿酸结石、羟基磷灰石、胱氨酸结石这四种纯结石年龄之间经统计分析,不具有显著性差异,男女患儿发病情况经统计分析,具有显著性差异。对比体内、外草酸钙结石、羟基磷灰石、尿酸结石、胱氨酸结石的扫描CT值在80kV、120kV和40kV下经统计分析,不具有显著性差异。不同的结石采用DSCT法(80kV和140kV)时CT值的差值和DEI值经统计学分析,具有显著性差异;采用常规扫描方法和DSCT法测定的ED值、CTDIvol值和DLP值经统计分析,均具有显著性差异(P<0.05),其中DSCT法均高于常规扫描法。结论 四种纯结石在不同电压下进行体内或体外扫描其CT值均无显著性差异,可见CT可作为临床上分析儿童上尿路结石成分的准确方法之一。结合CT值测量及DSCT分析软件可显著提高诊断的准确性,可在临床上推广应用。 展开更多
关键词 双源ct 双能量成像 上尿路结石 儿童 诊断价值
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肺磨玻璃结节消融治疗前后CT影像变化与疗效的关系
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作者 杨瑞山 王玲玲 解耀锃 《中国CT和MRI杂志》 2025年第1期60-62,共3页
目的 探讨肺磨玻璃结节(GGN)消融治疗前后CT影像变化及与疗效的关系。方法 选取2021年4月至2023年12月在本院行M WA治疗的90例GGN患者为研究对象。患者入院后均行微波消融术(MWA)治疗,于治疗前、治疗后1、3、6个月使用能谱CT检查,并根... 目的 探讨肺磨玻璃结节(GGN)消融治疗前后CT影像变化及与疗效的关系。方法 选取2021年4月至2023年12月在本院行M WA治疗的90例GGN患者为研究对象。患者入院后均行微波消融术(MWA)治疗,于治疗前、治疗后1、3、6个月使用能谱CT检查,并根据治疗后6个月患者疗效,将其分为有效组和无效组。结果 有效组患者治疗后1个月病灶最大径较治疗前增加,治疗后3、6个月病灶最大径较治疗后1个月逐渐减小(P<0.05),无效组患者治疗后1个月病灶最大径较治疗前增加,治疗后3个月病灶最大径较治疗后1个月减小,治疗后6个月后病灶最大径较治疗后3个月增加(P<0.05),且与无效组比较,有效组治疗后1、3、6个月的病灶最大径更小(P<0.05)。有效组患者治疗前、治疗后1、3、6个月的IC和NIC比较(P<0.05),治疗后6个月的IC低于治疗前,治疗后1、6个月的N IC低于治疗前(P<0.05),无效组治疗前、治疗后1、3、6个月的IC和NIC比较(P>0.05),治疗后6个月的IC和NIC低于治疗前(P<0.05),且与无效组比较,有效组治疗后6个月的IC和NIC更低(P<0.05)。结论 能谱CT可以较好反映MWA治疗前后GGN患者CT影像变化,且治疗后6个月的能谱CT参数对患者疗效具有评估价值。 展开更多
关键词 肺磨玻璃结节 消融 ct影像 疗效
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能谱CT单能量成像对结直肠癌供血动脉图像质量及辐射剂量的影响
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作者 刘海燕 邱晓晖 +3 位作者 章辉庆 锁咏梅 王超 王亚丽 《中国CT和MRI杂志》 2025年第1期159-161,共3页
目的 探讨能谱CT单能量成像对结直肠癌供血动脉图像质量及辐射剂量的影响。方法 选取医院2021年1月至2022年10月收治的92例结直肠癌患者,依据是否接受能谱CT单能量扫描分为常规CT组(n=33)与能谱CT组(n=59),将能谱组CT依据扫描能量分为50... 目的 探讨能谱CT单能量成像对结直肠癌供血动脉图像质量及辐射剂量的影响。方法 选取医院2021年1月至2022年10月收治的92例结直肠癌患者,依据是否接受能谱CT单能量扫描分为常规CT组(n=33)与能谱CT组(n=59),将能谱组CT依据扫描能量分为50keV组、70keV组、90keV组、110keV组,对比不同组别患者动脉期、静脉期肿瘤病灶的对比噪声比(CNR)、信噪比(SNR)及图像质量主观评分,同时比较不同组别扫描辐射剂量。结果 动脉期常规CT组与能谱CT各能量组间CNR、SNR、主观评分比较,差异均有统计学意义(P<0.05);且能谱CT组中50keV组动脉期CNR大于常规组及其他keV组,差异有统计学意义(P<0.05);静脉期常规CT组与能谱CT各能量组间CNR、SNR、主观评分比较,差异均有统计学意义(P<0.05);且能谱CT组中50keV组静脉期CNR、主观评分大于常规组及其他keV组,差异有统计学意义(P<0.05);两组DLP比较,差异无统计学意义(P>0.05);能谱CT组动脉期、静脉期及延迟期扫描有效辐射剂量均低于非能谱组,差异有统计学意义(P<0.05)。结论 与常规CT扫描相比,采用能谱CT单能量成像可降低辐射剂量,且应用50keV单能量重建可得到质量优异的结直肠癌供血动脉CT图像。 展开更多
关键词 结直肠癌 能谱ct 单能量成像 信噪比 对比噪声比
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弥漫大B细胞淋巴瘤^(18)F-FDG PET/CT特点及预测骨髓浸润的价值
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作者 杨满 黄琰 +4 位作者 孙凤霞 张灵秀 朱璐遥 刘宪凯 王秀峰 《中国CT和MRI杂志》 2025年第1期180-182,共3页
目的探讨弥漫大B细胞淋巴瘤(DLBCL)18氟-脱氧葡萄糖(^(18)F-FDG)正电子发射断层/计算机断层扫描(PET/CT)特点及预测骨髓浸润的价值。方法回顾性分析70例经病理确诊为DLBCL患者的^(18)F-FDG PET/CT影像资料,以PET/CT存在局灶性骨髓浸润... 目的探讨弥漫大B细胞淋巴瘤(DLBCL)18氟-脱氧葡萄糖(^(18)F-FDG)正电子发射断层/计算机断层扫描(PET/CT)特点及预测骨髓浸润的价值。方法回顾性分析70例经病理确诊为DLBCL患者的^(18)F-FDG PET/CT影像资料,以PET/CT存在局灶性骨髓浸润灶认定为骨髓浸润,根据是否发生骨髓浸润分为骨髓浸润组和骨髓正常组。其中骨髓浸润组分为局部浸润、弥漫浸润、局部伴弥漫浸润三组。观察代谢参数最大标准化摄取值(SUVmax)、肿瘤代谢体积(MTV)、病灶糖酵解总量(TLG)值,使用Spearman分析影像参数与Ann Arbor分期的相关性。绘制受试者工作特征曲线(ROC)分析PET/CT对骨髓浸润的诊断价值。结果经^(18)F-FDG PET/CT检查发现,骨髓浸润16例(22.86%),骨髓正常54例(78.14%),骨髓浸润中,局部浸润2例(12.50%)、弥漫浸润4例(25.00%)、局部伴弥漫浸润10例(62.50%);对比骨髓浸润组与骨髓正常组的^(18)F-FDGPET/CT参数发现,骨髓浸润组SUVmax、MTV和TLG值均高于骨髓正常组(P<0.05);对比不同临床分期的^(18)F-FDG PET/CT参数发现,4个临床分期的SUVmax、MTV和TLG值差异显著,均随着临床分期的进程而升高(P<0.05);Spearman分析显示,SUVmax、MTV和TLG与临床分期均成正相关(r=0.944,r=0.569,r=0.982,P均<0,001);SUVmax、MTV和TLG诊断骨髓浸润的AUC的面积分别为0.999、0.700、0.994(P均<0.05)。结论^(18)F-FDG PET/CT诊断DLBCL患者效能较高,其影像参数均呈现较高水平,与临床分期具有相关性,且其对骨髓浸润诊断价值较高。 展开更多
关键词 弥漫大B细胞淋巴瘤 ^(18)氟-脱氧葡萄糖 PET/ct 骨髓浸润
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CT放射组学鉴别诊断周围型小细胞肺癌和非小细胞肺癌的价值研究
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作者 靳强 高俊萍 +2 位作者 王欢 江涛 孙红红 《中国CT和MRI杂志》 2025年第1期47-49,共3页
目的 本研究旨在评估C T放射学方法鉴别周围型小细胞肺癌和非小细胞肺癌的研究,以期为临床诊治提供参考。方法回顾性研究原发性肺癌患者的临床资料,利用诊断后、治疗前的肺部CT图像对肺癌进行分割。从基于直方图的统计、肿瘤图像纹理分... 目的 本研究旨在评估C T放射学方法鉴别周围型小细胞肺癌和非小细胞肺癌的研究,以期为临床诊治提供参考。方法回顾性研究原发性肺癌患者的临床资料,利用诊断后、治疗前的肺部CT图像对肺癌进行分割。从基于直方图的统计、肿瘤图像纹理分析及其小波变换中提取放射学特征。特征选择采用最小冗余度和最大相关法。用多层人工神经网络建立预测模型,用受试者工作特征曲线(AUC)下面积评价SCLC/NSCLC腺癌分类器的性能。结果69例小细胞肺癌和34例非小细胞肺癌患者相比,小细胞肺癌组男性患者和吸烟者多于非小细胞肺癌组(P<0.05)。我们的SCLC/NSCLC分类器的总体性能AUC为0.93(95%可信区间=[0.85,0.97],灵敏度=0.85,特异度=0.85)。添加如吸烟史等临床数据,可略微改善性能。排名最靠前的放射学特征主要是纹理特征。结论 CT放射组学能定量反映肿瘤的异质性,可用于肺癌亚型的鉴别诊断,效果满意。用小波变换技术对CT图像进行处理,增强了小细胞肺癌/非小细胞肺癌的放射学特征。 展开更多
关键词 ct 周围型小细胞肺癌 非小细胞肺癌 放射学特征
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光谱CT融合补偿策略在冠状动脉CT血管成像中的应用
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作者 马一鸣 姚梅 +5 位作者 牡丹 张鑫 刘任远 张冰 杨尚文 李清霞 《分子影像学杂志》 2025年第1期64-69,共6页
目的探讨在冠状动脉CT血管成像中,使用光谱CT(IQon CT)联合补偿策略技术是否能在限制总辐射吸收率的同时保证图像质量。方法回顾性分析2021年1月~2023年12月南京鼓楼医院收治的80例受试者的临床资料,将其分为A、B两组,40例/组。A组使用1... 目的探讨在冠状动脉CT血管成像中,使用光谱CT(IQon CT)联合补偿策略技术是否能在限制总辐射吸收率的同时保证图像质量。方法回顾性分析2021年1月~2023年12月南京鼓楼医院收治的80例受试者的临床资料,将其分为A、B两组,40例/组。A组使用100 mL对比剂,注射流速为5.0 mL/s,行传统剂量IQon CT扫描(管电压120 kV,320 mgI/mL威视派克注射液);B组使用40 mL对比剂,注射流速为3.5 mL/s,行补偿策略IQon CT扫描(管电压70 kV,270 mgI/mL威视派克注射液)。比较两组受试者的主、客观评价[对比噪声比(CNR)、信噪比(SNR)],计算辐射剂量[容积剂量指数(CTDIvoI)、剂量长度乘积(DLP)、有效剂量(ED)]与对比剂碘吸收系数。结果两组图像主观评价差异无统计学意义(P>0.05),AB两组主观质量评分≥3分,两组图片一致性高(P<0.05)。两组图像各亚组的CT值、SNR和CNR差异有统计学意义(P<0.05);A组图像CT值均低于B组,其中B组在40 keV单能量图像具有最优的CT值、CNR和SNR。B组CTDIvoI减少66.7%,DLP减少83.8%,ED减少75.6%(P<0.05)。B组对比剂碘吸收系数比A组降低70.1%(85.2 g vs 25.4 g)。结论IQon CT联合补偿策略在冠状动脉CT血管成像中的应用前景广阔,具有重要的临床应用价值与推广前景。 展开更多
关键词 光谱ct ct血管成像 补偿策略
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CBCT测量解剖参数在上颌第一磨牙缺失患者种植术前的临床应用价值
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作者 张磊 张蕊 +1 位作者 何晓彤 赵晶 《医学综述》 CAS 2025年第1期125-128,共4页
目的探究应用锥形束CT(CBCT)测量解剖参数在上颌第一磨牙缺失患者种植术前的临床应用价值。方法选取2022年5月至2024年5月中日友好医院收治的上颌第一磨牙缺失且拍摄CBCT的89例患者,比较不同性别、年龄、缺失侧、缺失时间上颌第一磨牙... 目的探究应用锥形束CT(CBCT)测量解剖参数在上颌第一磨牙缺失患者种植术前的临床应用价值。方法选取2022年5月至2024年5月中日友好医院收治的上颌第一磨牙缺失且拍摄CBCT的89例患者,比较不同性别、年龄、缺失侧、缺失时间上颌第一磨牙缺失患者残余牙槽嵴的高度和宽度的差异,并观察患者上颌窦外侧壁血管分型。结果不同年龄、缺失侧、缺失时间上颌第一磨牙缺失患者残余牙槽嵴的高度和宽度比较差异无统计学意义(P>0.05);不同性别上颌第一磨牙缺失患者残余牙槽嵴的高度比较差异无统计学意义(P>0.05),上颌第一磨牙缺失男性患者残余牙槽嵴的宽度大于女性患者[(9.0±2.7)mm比(7.5±2.0)mm](P<0.01);在89例上颌第一磨牙缺失患者的178侧上颌窦中,69.10%(123/178)的上颌窦外侧壁存在血管,其中骨内型占比最高,为70.73%(87/123)。结论CBCT可用于测量残余牙槽嵴的高度和宽度以及评估上颌窦外侧壁血管分型,可为种植术提供相关的术前指导。 展开更多
关键词 上颌第一磨牙缺失 锥形束ct 残余牙槽嵴的高度 残余牙槽嵴的宽度
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基于能谱CTA的下肢动脉闭塞性疾病支架效果显示评价
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作者 黄欣 丁宁宁 +5 位作者 周丽 赵文哲 李达亮 刘哲 杨健 金超 《西安交通大学学报(医学版)》 北大核心 2025年第1期178-183,共6页
目的 探讨能谱CT单能量成像技术在提高下肢动脉硬化闭塞性疾病支架置入CT血管成像(CTA)图像质量及支架显示中的临床价值。方法 回顾性分析我院接受下肢动脉能谱CTA检查的20例下肢动脉慢性闭塞性疾病支架植入患者的图像资料[年龄(65.61&#... 目的 探讨能谱CT单能量成像技术在提高下肢动脉硬化闭塞性疾病支架置入CT血管成像(CTA)图像质量及支架显示中的临床价值。方法 回顾性分析我院接受下肢动脉能谱CTA检查的20例下肢动脉慢性闭塞性疾病支架植入患者的图像资料[年龄(65.61±9.65)岁;男/女:16/4]。原始图像重建为7组单能量图像(40~100 keV)、120 kVp、虚拟平扫(VUE)和去金属伪影(MAR)技术图像。图像经去骨处理后,以容积重建(VR)、最大密度投影(MIP)和曲面重建(CPR)显示支架,并进行客观和主观评估,通过单因素方差分析进行比较。结果 与其他重建组图像相比,80 keV和MAR图像评分最高(P<0.01)。结论 80 keV单能量成像技术和MAR提高了下肢动脉支架内腔和结构的图像质量,为临床医师提供了更高的诊断价值。 展开更多
关键词 下肢动脉慢性闭塞性疾病 能谱ct血管成像 单能量成像 下肢动脉 动脉支架
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双肺下叶静脉解剖分型MSCT评价及临床应用探讨
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作者 王娟 郭龙军 +2 位作者 滕佳岐 陈玉昆 贺文 《中国临床解剖学杂志》 北大核心 2025年第1期31-39,共9页
目的应用多层螺旋CT(MSCT)对健康人双肺下叶肺静脉解剖及引流模式分型,阐述其特点,为解剖性肺段切除术靶静脉解剖分型提供帮助。方法收集200例肺部无异常胸部CT影像资料,通过VR重建获得静脉解剖及引流模式图,观察并统计各静脉分型出现... 目的应用多层螺旋CT(MSCT)对健康人双肺下叶肺静脉解剖及引流模式分型,阐述其特点,为解剖性肺段切除术靶静脉解剖分型提供帮助。方法收集200例肺部无异常胸部CT影像资料,通过VR重建获得静脉解剖及引流模式图,观察并统计各静脉分型出现率。结合重建5mm轴位MIP图,选择三个重点观察平面,辨识对应各分型。结果V6根据干的数量分为两种类型:单干(88%)、双干(12%),单干为最常见的类型。此外,S6和S10之间存在独立节段S^(*),有独立的节段性支气管(B)和动脉(A)。双下肺基底静脉的特点是放射状排列。内侧基底段静脉(V_(7))大部分分支管径纤细。前基底节段、外侧基底节段和后基底节段静脉(V_(8),V_(9),V_(10))分支模式分为以下四种组合类型:V_(8)+V_(9)/V_(10)型、V_(8)/V_(9)+V_(10)型、V_(8)+V_(9)+V_(10)/V_(10)型、V_(8)+V_(9)/V_(9)+V_(10)型,各型占比率各有不同。结论肺静脉解剖分型及引流模式图可作为解剖识别常规手段,为肺段切除术前肺静脉精细解剖评价提供依据,本研究所获数据可作为3D-CT图像的补充,为肺段切除术靶静脉及支气管精细解剖了解提供帮助。 展开更多
关键词 双肺下叶 静脉引流 支气管 多层螺旋ct 解剖性肺段切除术
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