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Gamma knife treatment for refractory epilepsy in seizure focus localized by positron emission tomography/CT
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作者 Xia Bai Xuemei Wang +4 位作者 Hongwei Wang Shigang Zhao Xiaodong Han Linjun Hao Xiangcheng Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第36期2937-2943,共7页
A total of 80 patients with refractory epilepsy were recruited from the Inner Mongolia Medical College Affiliated Hospital. The loci of 60% of the patients could be positioned using a combined positron emission tomogr... A total of 80 patients with refractory epilepsy were recruited from the Inner Mongolia Medical College Affiliated Hospital. The loci of 60% of the patients could be positioned using a combined positron emission tomography/CT imaging modality. Hyper- and hypometabolism foci were examined as part of this study. Patients who had abnormal metabolism in positron emission tomography/CT imaging were divided into intermittent-phase group and the seizure-phase group. The intermittent-phase group was further divided into a single-focus group and a multiple-foci group according to the number of seizure foci detected by imaging. Following gamma knife treatment, seizure frequency was significantly lower in the intermittent-phase group and the seizure-phase group. Wieser's classification reached Grade I or II in nearly 40% of patients. Seizure frequency was significantly lower following treatment, but Wieser's classification score was significantly higher in the seizure-phase group compared with the intermittent-phase group. Seizure frequency was significantly lower following treatment in the single-focus group, but Wieser's classification score was significantly higher in the single-focus group as compared with the multiple-foci group. 展开更多
关键词 EPILEPSY SEIZURE positron emission tomography/ct gamma knife radiosurgery METABOLISM 18F-FLUORODEOXYGLUCOSE neural regeneration
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Dynamic ^(18)F-fluorodeoxyglucose positron emission tomography/CT in hibernoma: enhanced tracer uptake mimicking liposarcoma
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作者 Christos Sachpekidis Safwan Roumia +1 位作者 Matthias Schwarzbach Antonia Dimitrakopoulou-Strauss 《World Journal of Radiology》 CAS 2013年第12期498-502,共5页
We report on two cases of patients with fat-equivalent masses in computed tomography(CT),referred to our department for dynamic positron emission tomography/CT(dPET/CT)with18F-fluorodeoxyglucose(18FFDG)in order to inv... We report on two cases of patients with fat-equivalent masses in computed tomography(CT),referred to our department for dynamic positron emission tomography/CT(dPET/CT)with18F-fluorodeoxyglucose(18FFDG)in order to investigate their dignity.Both qualitative and quantitative information,as derived from dPET/CTs,couldn’t exclude a high-grade liposarcoma:Visual evaluation,revealed a large hypermetabolic focus of intense18F-FDG uptake in each patient(average SUVs 8.3 and 11.3).Regression-based parametric imaging demonstrated an enhanced distribution volume,which correlates to perfusion,and a high phosphorylation rate that correlates to cell viability.Kinetic analysis,based on a two-tissue compartment model demonstrated an enhanced FDG transport k1and an enhanced phosphorylation rate k3.A non-compartmental approach based on fractal dimension revealed also enhanced values.However,final diagnosis was based on biopsy,which revealed hibernoma,a benign brown fat tumor.Brown adipose contains increased numbers of mitochondria and a high-rate of glucose metabolism.Therefore,they have increased FDG uptake.The evaluation of lipomatous lesions on CT,with high FDG uptake,should include the possibility of hibernoma as a differential diagnosis. 展开更多
关键词 Hibernoma DYNAMIC POSITRON emission tomography/ct 18F-FLUORODEOXYGLUCOSE Kinetic Modeling Parametric imaging
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Three-dimensional characterization of intermetallic compound formation in magnesium alloys with micro X-ray computed tomography
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作者 SUN Wei HU Xiao-juan +5 位作者 DENG Yang-chao YANG Yang YAO Hu ZHANG Yong-hong ZHANG Rui-feng ZENG Guang 《Journal of Central South University》 2026年第1期160-174,共15页
This comprehensive study investigates the formation and evolution of intermetallic compounds during the solidification process of magnesium alloys using advanced micro X-ray computed tomography.By analyzing both commo... This comprehensive study investigates the formation and evolution of intermetallic compounds during the solidification process of magnesium alloys using advanced micro X-ray computed tomography.By analyzing both common industrial Mg-Al-Zn alloys and a novel rare earth-containing Mg-Ni-Gd-Y alloy,we aim to characterize the nucleation,growth,and distribution of Al-Mn and eutectic intermetallics across various stages of solidification.The non destructive imaging technique employed in this research provides high-resolution,three-dimensional insights into the microstructural development,allowing for a detailed examination of the morphology,spatial arrangement,and interconnectivity of intermetallic phases.This approach overcomes limitations of traditional two-dimensional metallographic methods,offering a more comprehensive understanding of the complex three-dimensional structures formed during solidification. 展开更多
关键词 magnesium alloy X-ray computed tomography SOLIDIFICATION INTERMETALLICS DEFEctS
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Optical coherence tomography for surgical demarcation of GI tumor margins for accelerated decision-making during the surgical resection of tumors
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作者 Mohamed Nijas Veluthedath Anuradha Sekaran +3 位作者 Manjoosha R Yerrapragada Pradeep Rebala Duvvuru Nageshwar Reddy Renu John 《Journal of Innovative Optical Health Sciences》 2026年第2期116-128,共13页
Gastric cancer,including stomach tumors,poses significant health challenges due to late-stage diagnosis and limited early detection methods.Accurate imaging and precise tumor margin demarcation are critical for effect... Gastric cancer,including stomach tumors,poses significant health challenges due to late-stage diagnosis and limited early detection methods.Accurate imaging and precise tumor margin demarcation are critical for effective treatment planning and improved patient outcomes.Conventional imaging techniques,such as endoscopy and histopathology,provide valuable diagnostic information but cannot offer real-time assessment.We aim to explore the application of optical coherence tomography(OCT),combined with statistical and machine learning methods,for rapid tumor margin demarcation in gastrointestinal(GI)cancer tissues in exvivo.GI tumor specimens from 17 patients were imaged intraoperatively with OCT.Quantitative features were extracted from the images,and statistical and machine learning analyses were applied to distinguish tissue types.Subsequent histopathological evaluation was used as the reference standard for validation.The combination of OCT imaging and data-driven analysis enables clear differentiation between healthy,marginal and tumor tissues in near real-time.The KNN model achieved the highest classification accuracy(0.921±0.040),with SVM(0.906±0.038)and Extra Trees(0.901±0.034)also demonstrating robust performance in discriminating tissue margins.OCT findings demonstrate strong agreement with histopathology.Integrated with statistical and machine learning techniques,OCT enables rapid assessment of GI tumor margins.This approach provides quantitative objectivity and real-time feedback,closely approximating histopathological analysis and supporting improved surgical decision-making. 展开更多
关键词 Optical coherence tomography gastrointestinal tumor tumor demarcation optical biopsy
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C-SegNet:a practical approach for automated diabetic macular edema segmentation in optical coherence tomography images
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作者 Zhi-Yuan Guan Ge Deng +6 位作者 Shi-Long Shi Zhen Tang Xian-Kun Dong Qiu-Yi Li Shu-Jing Shen Yong-Ling He Xue-Jun Qiu 《Biomedical Engineering Communications》 2026年第2期15-22,共8页
Background:Diabetic macular edema is a prevalent retinal condition and a leading cause of visual impairment among diabetic patients’Early detection of affected areas is beneficial for effective diagnosis and treatmen... Background:Diabetic macular edema is a prevalent retinal condition and a leading cause of visual impairment among diabetic patients’Early detection of affected areas is beneficial for effective diagnosis and treatment.Traditionally,diagnosis relies on optical coherence tomography imaging technology interpreted by ophthalmologists.However,this manual image interpretation is often slow and subjective.Therefore,developing automated segmentation for macular edema images is essential to enhance to improve the diagnosis efficiency and accuracy.Methods:In order to improve clinical diagnostic efficiency and accuracy,we proposed a SegNet network structure integrated with a convolutional block attention module(CBAM).This network introduces a multi-scale input module,the CBAM attention mechanism,and jump connection.The multi-scale input module enhances the network’s perceptual capabilities,while the lightweight CBAM effectively fuses relevant features across channels and spatial dimensions,allowing for better learning of varying information levels.Results:Experimental results demonstrate that the proposed network achieves an IoU of 80.127%and an accuracy of 99.162%.Compared to the traditional segmentation network,this model has fewer parameters,faster training and testing speed,and superior performance on semantic segmentation tasks,indicating its highly practical applicability.Conclusion:The C-SegNet proposed in this study enables accurate segmentation of Diabetic macular edema lesion images,which facilitates quicker diagnosis for healthcare professionals. 展开更多
关键词 multi-scale input diabetic macular edema image segmentation optical coherence tomography
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High-resolution 3D shallow crustal structure of Urumqi foreland thrust tectonic belt,northern Tianshan,based on ambient noise tomography
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作者 Xiang Huang Zhengyang Qiang +1 位作者 Weitao Wang Yuan Yao 《Earthquake Science》 2026年第1期86-96,共11页
The Urumqi foreland thrust tectonic belt exhibits complex geological structures and strong seismicity.Imaging its shallow crustal structure is of great significance for understanding its tectonic mechanism and seismog... The Urumqi foreland thrust tectonic belt exhibits complex geological structures and strong seismicity.Imaging its shallow crustal structure is of great significance for understanding its tectonic mechanism and seismogenic environment.We obtained a high-resolution S-wave velocity model of the shallow crust at depths of 0–8 km using ambient noise tomography applied to data from a dense seismic array.Sediments are generally thinner in the southeast and thicker in the northwest,with a maximum thickness of more than 8 km.Variations in the velocity structure near the Xishan,Wanyaogou,and Yamalike faults indicate that their formation was related to differences in the physical properties on either side of the fault.In addition,the faults exhibit thrusting of the low-velocity sides towards the high-velocity sides.In the study area,earthquakes rarely occur at depths of less than 3 km and are mostly concentrated in the high-velocity zone in the southern part.Below 3 km depth,more earthquakes were observed,mainly distributed near faults or in relatively high-velocity areas in the southern part.This suggests that high-velocity structures are more prone to stress accumulation,resulting in earthquakes.At 6–8 km depth,the densely distributed earthquakes in the northwestern part of the Bogda mountains are well-aligned with the northwest-oriented low-velocity zone observed in this study,suggesting that this weak zone likely controls seismicity in this area. 展开更多
关键词 ambient noise tomography shallow crustal structure thrust fault SEISMICITY Urumqi depression
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Combined multidetector computed tomography and gastrointestinal endoscopy for gastric cancer screening,preoperative staging,and lymph node metastasis detection
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作者 Le-Ping Ye Yan-Ping Zhang +4 位作者 Gang Chen Yi-Xian Wu Cheng-Long He Dong Wang Qiao Mei 《World Journal of Gastrointestinal Oncology》 2026年第1期200-210,共11页
BACKGROUND Early screening,preoperative staging,and diagnosis of lymph node metastasis are crucial for improving the prognosis of gastric cancer(GC).AIM To evaluate the diagnostic value of combined multidetector compu... BACKGROUND Early screening,preoperative staging,and diagnosis of lymph node metastasis are crucial for improving the prognosis of gastric cancer(GC).AIM To evaluate the diagnostic value of combined multidetector computed tomography(MDCT)and gastrointestinal endoscopy for GC screening,preoperative staging,and lymph node metastasis detection,thereby providing a reference for clinical diagnosis and treatment.METHODS In this retrospective study clinical and imaging data of 134 patients with suspected GC who were admitted between January 2023 and October 2024 were initially reviewed.According to the inclusion and exclusion criteria,102 patients were finally enrolled in the analysis.All enrolled patients had undergone both MDCT and gastrointestinal endoscopy examinations prior to surgical intervention.Preoperative clinical staging and lymph node metastasis findings were compared with pathological results.RESULTS The combined use of MDCT and gastrointestinal endoscopy demonstrated a sensitivity of 98.53%,specificity of 97.06%,accuracy of 98.04%,positive predictive value of 98.53%,and negative predictive value of 97.06%for diagnosing GC.These factors were all significantly higher than those of MDCT or endoscopy alone(P<0.05).The accuracy rates of the combined approach for detecting clinical T and N stages were 97.06%and 92.65%,respectively,outperforming MDCT alone(86.76% and 79.41%)and endoscopy alone(85.29% and 70.59%)(P<0.05).Among 68 patients with confirmed GC,50(73.53%)were pathologically diagnosed with lymph node metastasis.The accuracy for detecting lymph node metastasis was 66.00%with endoscopy,76.00%with MDCT,and 92.00% with the combined approach,all with statistically significant differences(P<0.05).CONCLUSION The combined application of MDCT and gastrointestinal endoscopy enhanced diagnostic accuracy for GC,provided greater consistency in preoperative staging,and improved the detection of lymph node metastasis,thereby demonstrating significant clinical utility. 展开更多
关键词 Multidetector computed tomography Gastrointestinal endoscopy Gastric cancer Preoperative staging Lymph node metastasis
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Application of electrical impedance tomographyguided PEEP titration in acute respiratory distress syndrome patients with intra-abdominal hypertension
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作者 Hui Wen Maiying Fan +5 位作者 Junliang Xiao Zhiqun Liu Xiaohua Liu Shuzhen Mao Xiaotong Han Fengling Ning 《World Journal of Emergency Medicine》 2026年第1期70-75,共6页
BACKGROUND:Individualized positive end-expiratory pressure(PEEP)titration is a crucial technique in mechanical ventilation therapy for acute respiratory distress syndrome(ARDS)patients with intra-abdominal hypertensio... BACKGROUND:Individualized positive end-expiratory pressure(PEEP)titration is a crucial technique in mechanical ventilation therapy for acute respiratory distress syndrome(ARDS)patients with intra-abdominal hypertension(IAH).This study aimed to evaluate the eff ectiveness of electrical impedance tomography(EIT)-guided PEEP titration in this population.METHODS:This prospective study enrolled 36 ARDS patients,including 22 patients with IAH and 14 without IAH.All the patients underwent EIT-guided PEEP titration at the intersection point between alveolar overdistension and collapse during a decremental PEEP trial.The changes in pulmonary ventilation distribution,respiratory mechanics and hemodynamics during the titration process were observed.RESULTS:After EIT-guided PEEP titration was performed,the PEEP,peak inspiratory pressure and plateau pressure increased significantly(P<0.05).Furthermore,no significant differences were observed in respiratory system compliance,tidal volume,driving pressure,or the 4*DP+RR index between the two groups(P>0.05).The mechanical power increased in the non-IAH(NIAH)group after PEEP titration(P<0.05).Ventilation in gravity-dependent lung regions significantly increased(P<0.05),and the oxygenation index(PaO2/FiO2)improved signifi cantly(P<0.05)in both groups.However,blood pressure,heart rate,respiratory rate,central venous pressure,and lactate levels did not signifi cantly change.In the IAH group,the PaO2/FiO2 ratio improved less than that in the NIAH group did(P<0.05).CONCLUSION:In our study,individualized PEEP titration guided by EIT improved oxygenation in ARDS patients with concomitant IAH without signifi cantly aff ecting hemodynamics.The presence of IAH may limit the improvement of oxygenation during EIT-guided PEEP titration. 展开更多
关键词 Acute respiratory distress syndrome Positive end-expiratory pressure Electrical impedance tomography Intra-abdominal pressure
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Chronic alcohol consumption on retinal microcirculation in healthy subjects:an optic coherence tomography angiography study
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作者 Dilan Yildiz Tahsin Uzundede +2 位作者 Akin Cakir Gamze Karatas Busra Coban 《International Journal of Ophthalmology(English edition)》 2026年第2期326-332,共7页
AIM:To investigate the effects of chronic alcohol consumption on retinal microcirculation by comparing different alcohol-consuming groups using optical coherence tomography(OCT)and OCT angiography(OCTA).METHODS:This o... AIM:To investigate the effects of chronic alcohol consumption on retinal microcirculation by comparing different alcohol-consuming groups using optical coherence tomography(OCT)and OCT angiography(OCTA).METHODS:This observational clinical study utilized a cross-sectional and prospective design,focusing on chronic alcohol consumers alongside a non-consuming control group.OCT/OCTA imaging parameters including central retinal subfield thickness(CST),subfoveal choroidal thickness(SCT),foveal avascular zone(FAZ)and vessel density(VD)in the superficial and deep capillary plexuses in both the macular and optic disc(OD)regions were recorded.Data were analyzed using SPSS 15.0;descriptive statistics were reported,group comparisons were performed with Chisquare,Kruskal–Wallis,and Bonferroni-corrected Mann–Whitney U tests,and relationships were assessed using Spearman correlation,with statistical significance set at P<0.05.RESULTS:A total of 160 eyes of 160 participants(110 females and 50 males with mean age 38.7±9.9y)who don’t smoke were divided into five groups:never,occasional,monthly,weekly and daily drinkers.The mean CST was 216.6±14.2μm and the mean SCT was 358.9±84.5μm.There was no statistically significantly difference in CST and SCT among the groups(P=0.890,0.799).Foveal superficial capillary plexuses(SCPs)VD was higher in monthly drinkers compared to occasional drinkers(P=0.015).Foveal VD in deep capillary plexus was also higher in monthly drinkers than in never and occasional drinkers(P=0.004,0.006).Nasal SCPs VD at the OD was higher in monthly drinkers compared to never drinkers(P=0.005).There was no significant difference FAZ area among the groups(P=0.071).CONCLUSION:Both superficial and deep microvascular structures in the inferior quadrants of macula are positively correlated with frequency of alcohol use.Also in our study results is that the monthly drinker group has uniquely higher VDs in both macula and OD.This leads us to consider moderate alcohol consumption may also have protective effects on retinal microcirculation. 展开更多
关键词 alcohol consumption foveal avascular zone retinal microcirculation optical coherence tomography angiography vessel density
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Therapeutic effects of low-intensity transcranial focused ultrasound stimulation on ischemic stroke in rats:An in vivo evaluation using electrical impedance tomography
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作者 Jiecheng Guo Sixuan He +4 位作者 Li Yan Lei Wang Xuetao Shi Huijing Hu Le Li 《Neural Regeneration Research》 2026年第3期1183-1190,共8页
Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance to... Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance tomography enables real-time monitoring of changes in cerebral blood perfusion within the ischemic brain,but investigating the feasibility of using this method to assess post-stroke rehabilitation in vivo remains critical.In this study,ischemic stroke was induced in rats through middle cerebral artery occlusion surgery.Transcranial focused ultrasound stimulation was used to treat the rat model of ischemia,and electrical impedance tomography was used to measure impedance during both the acute stage of ischemia and the rehabilitation stage following the stimulation.Electrical impedance tomography results indicated that cerebral impedance increased after the onset of ischemia and decreased following transcranial focused ultrasound stimulation.Furthermore,the stimulation promoted motor function recovery,reduced cerebral infarction volume in the rat model of ischemic stroke,and induced the expression of brain-derived neurotrophic factor in the ischemic brain.Our results also revealed a significant correlation between the impedance of the ischemic brain post-intervention and improvements in behavioral scores and infarct volume.This study shows that daily administration of transcranial focused ultrasound stimulation for 20 minutes to the ischemic hemisphere 24 hours after cerebral ischemia enhanced motor recovery in a rat model of ischemia.Additionally,our findings indicate that electrical impedance tomography can serve as a valuable tool for quantitatively evaluating rehabilitation after ischemic stroke in vivo.These findings suggest the feasibility of using impedance data collected via electrical impedance tomography to clinically assess the effects of rehabilitatory interventions for patients with ischemic stroke. 展开更多
关键词 animal model brain stimulation electrical impedance tomography evaluation impedance noninvasive treatment real-time monitoring REHABILITATION STROKE transcranial focused ultrasound stimulation
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High-frequency emphasized neural network reconstruction method for in situ synchrotron radiation ultrafast computed tomography characterization
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作者 Jing-Wei Li Yu Xiao +3 位作者 Yong-Cun Li Xiao-Fang Hu Guo-Hao Du Feng Xu 《Nuclear Science and Techniques》 2026年第3期5-17,共13页
There is a contradiction between the evolution rate of materials and the time resolution of SR-CT characterization in the in situ synchrotron radiation computed tomography(SR-CT)characterization of ultrafast evolution... There is a contradiction between the evolution rate of materials and the time resolution of SR-CT characterization in the in situ synchrotron radiation computed tomography(SR-CT)characterization of ultrafast evolution process.The sampling strategy of the ultra-sparse angle is an effective method for improving time resolution.Accurate reconstruction under sparse sampling conditions has always been a bottleneck problem.In recent years,convolutional neural networks have shown outstanding advantages in sparse-angle CT reconstruction given the development of deep learning.However,existing ideas did not consider the expression of high-frequency details in neural networks,limiting their application in accurate SR-CT characterization.A novel high-frequency information-constrained deep learning network(HFIC-Net)is proposed in response to this problem.Additional high-frequency information constraints are added to improve the accuracy of the reconstruction results.Further,a series of numerical reconstruction experiments are conducted to verify this new method,and the results indicate that the reconstruction results of HFIC-Net method effectively improve reconstruction quality.This new method uses only eight-angle projections to achieve the reconstruction effect of the filtered backprojection method(FBP)method in 360 projections.The results of the HFIC-Net method demonstrate clear boundaries and accurate detailed structures,correcting the misinformation caused by using other methods.For quantitative evaluation,the SSIM used to evaluate image structure similarity is increased from 0.1951,0.9212,and 0.9308 for FBP,FBP-Conv,and DDC-Net,respectively,to 0.9620 for HFIC-Net.Finally,the results of actual SR-CT experimental data indicate that the new method can suppress artifacts and achieve accurate reconstruction,and it is suitable for the in situ SR-CT accurate characterization of ultxafast evolution process. 展开更多
关键词 Accurate SR-ct characterization ct reconstruction Sparse-angle ct reconstruction problem High-frequency information constrained Deep learning
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冠状动脉CTA团注追踪阈值触发时间与CT值预测和对比剂外渗的相关性研究
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作者 付玲 韩菲 +3 位作者 甘良英 刘卓 安备 程瑾 《中国循证心血管医学杂志》 2026年第2期195-200,共6页
目的分析CT冠状动脉造影检查中对比剂团注追踪阈值触发时间、CT值与对比剂外渗的关联性,为临床快速识别并处理对比剂外渗提供科学的参考依据。方法回顾性选取2022年1月至2023年12月于北京大学人民医院接受CT冠状动脉造影检查的1124例门... 目的分析CT冠状动脉造影检查中对比剂团注追踪阈值触发时间、CT值与对比剂外渗的关联性,为临床快速识别并处理对比剂外渗提供科学的参考依据。方法回顾性选取2022年1月至2023年12月于北京大学人民医院接受CT冠状动脉造影检查的1124例门诊患者作为研究对象,收集一般人口学资料。根据患者是否发生对比剂外渗分为外渗组和未外渗组,再根据体重指数(BMI)、对比剂注射剂量及注射速度将患者分为4个亚组(组1:BMI提示偏瘦,注射剂量为48 mL,注射速度为4 mL/s;组2:BMI提示正常,注射剂量为54 mL,注射速度为4.5 mL/s;组3:BMI提示超重,注射剂量为60 mL,注射速度为5 mL/s;组4:BMI提示肥胖,注射剂量为66 mL,注射速度为5.5 mL/s)。统计所有患者的团注追踪阈值触发时间及CT值,比较外渗组和未外渗组患者的性别、年龄、文化程度、体质指数及CT值的变化,以及4个亚组的外渗情况。采用多因素Logistic回归分析对比剂外渗的危险因素,采用多元线性回归分析CT值及触发时间的影响因素。结果在1124例患者中,发生静脉外渗者25例(2.22%)。外渗组和未外渗组患者的性别、年龄、文化程度、BMI比较,差异无统计学意义(P>0.050);两组患者的CT值比较,差异有统计学意义(P<0.050)。4个亚组的外渗情况比较,差异无统计学意义(P>0.050)。多因素回归分析结果显示,性别、年龄、BMI、文化程度、亚组均非对比剂外渗的危险因素(P>0.050)。触发时间及CT值的多元线性回归分析结果显示,性别、文化程度、BMI均非二者的影响因素(P>0.050),年龄、组别是二者的影响因素(P<0.050)。结论基于团注追踪阈值触发时间及CT值预测CT冠状动脉造影检查中的对比剂外渗具有较高的科学性,可为临床评估对比剂外渗风险提供可靠的参考依据。 展开更多
关键词 ct冠状动脉造影 对比剂 团注追踪阈值触发法 外渗 触发时间 ct
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基于CT扫描技术的透水混凝土孔隙特性研究
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作者 徐丽娜 魏超 +2 位作者 丁旭 黄占芳 刘宁 《水电能源科学》 北大核心 2026年第1期114-118,共5页
为深入研究聚丙烯仿钢纤维透水混凝土的微观机理,采用CT扫描技术对试件进行扫描,通过三维数字重构技术建立了孔隙结构的可视化模型。基于图像分析方法对比研究了纤维改性前后材料内部孔隙系统的形态演变特征。结果表明,聚丙烯仿钢纤维... 为深入研究聚丙烯仿钢纤维透水混凝土的微观机理,采用CT扫描技术对试件进行扫描,通过三维数字重构技术建立了孔隙结构的可视化模型。基于图像分析方法对比研究了纤维改性前后材料内部孔隙系统的形态演变特征。结果表明,聚丙烯仿钢纤维的加入可有效提高试件的强度,但会抑制试块的透水性能,试块各层面孔隙率稳定在15%~20%之间,且连通孔隙占总孔隙的97%以上;未添加纤维的试块中大孔数量较少,但其体积占比较大;加入纤维后,部分大孔转化为中孔并抑制孔隙间的连通,从而改变孔隙结构。 展开更多
关键词 聚丙烯仿钢纤维透水混凝土 ct扫描 孔隙结构 透水性能
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冠状动脉CT血管造影及FFR-CT对冠心病患者心肌缺血的诊断价值
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作者 王华锋 张晓瑞 +3 位作者 高云云 王琦 相世峰 冯强 《广东医学》 2026年第1期64-69,共6页
目的分析冠状动脉CT血管造影(CCTA)及冠状动脉无创血流储备分数(FFR-CT)对冠心病患者心肌缺血的诊断价值。方法选取2022年5月至2024年5月该院收治的140例冠心病患者为研究对象,入院后均行冠状动脉造影(CAG)、FFR检查、CCTA,并计算FFR-CT... 目的分析冠状动脉CT血管造影(CCTA)及冠状动脉无创血流储备分数(FFR-CT)对冠心病患者心肌缺血的诊断价值。方法选取2022年5月至2024年5月该院收治的140例冠心病患者为研究对象,入院后均行冠状动脉造影(CAG)、FFR检查、CCTA,并计算FFR-CT,以FFR值≤0.8作为心肌缺血诊断标准并分为心肌缺血组、无心肌缺血组,比较心肌缺血组与无心肌缺血组的CCTA斑块特征参数指标(钙化积分、斑块总体积、钙化斑块体积、斑块负荷、重建指数、病变长度等)及FFR-CT值差异性,绘制受试者工作特征(ROC)曲线评估CCTA及FFR-CT对冠心病心肌缺血的诊断价值。结果心肌缺血组(FFR≤0.8)的CCTA钙化积分、斑块负荷、重建指数、病变长度及正性重构、餐巾环征比例高于无心肌缺血组(P<0.05),心肌缺血组FFR值、FFR-CT值低于无心肌缺血组(P<0.05),两组斑块总体积、钙化斑块体积比、低密度斑块、点状钙化比例差异无统计学意义(P>0.05);ROC曲线分析显示,以FFR为金标准,CCTA诊断冠心病患者心肌缺血的敏感度、特异度、阳性预测值、阴性预测值、曲线下面积均低于FFR-CT诊断(P<0.05)。结论FFR-CT诊断冠心病患者心肌缺血的效能较CCTA好,利于临床上对冠心病患者进行心肌缺血筛查。 展开更多
关键词 冠状动脉ct血管造影 冠状动脉无创血流储备分数 冠心病 心肌缺血
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改良呼吸运动补偿算法对肝右叶CT图像质量及病灶测量误差的相关性影响的研究
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作者 李囡馨 闫文貌 +3 位作者 耿长涛 王海阔 齐中 周楠 《中国医学装备》 2026年第2期47-51,共5页
目的:探讨呼吸运动补偿算法的改良对肝右叶病灶计算机体层扫描(CT)图像质量和病灶直径测量误差的影响及其相关性,为优化影像学评估提供依据。方法:采用前瞻性队列设计,纳入2022年1月至2024年12月首都医科大学附属北京天坛医院门诊就诊的... 目的:探讨呼吸运动补偿算法的改良对肝右叶病灶计算机体层扫描(CT)图像质量和病灶直径测量误差的影响及其相关性,为优化影像学评估提供依据。方法:采用前瞻性队列设计,纳入2022年1月至2024年12月首都医科大学附属北京天坛医院门诊就诊的160例肝右叶单发占位病变患者,按CT扫描时间顺序将2023年7月至2024年12月接诊的80例患者纳入改良组,2022年1月至2023年6月接诊的80例患者纳入未改良组,改良组应用经算法优化方案改良的呼吸运动补偿算法,未改良组采用设备固有的常规呼吸补偿算法。所有患者均行统一参数的CT双期增强扫描(平扫、动脉期、门脉期),观察图像质量(对比噪声比、信噪比)、图像主观评分(5分制,由资深放射科医师独立盲评)及病灶直径测量误差。采用组内相关系数与皮尔逊相关分析评估图像质量参数的一致性及其与测量误差的关联。结果:两组不同期相图像客观质量指标对比显示:改良组在平扫(t=7.384、8.265,P<0.05)、动脉期(t=8.127、6.987,P<0.05)和门脉期(t=7.942、7.153,P<0.05)的对比噪声比和信噪比均显著高于未改良组,其中对比噪声比在门脉期的组间差异最大,信噪比在平扫期差异最显著。改良组图像主观评分(4.21±0.63)分,较未改两组的(3.17±0.72)分显著提升,病灶直径测量误差显著降低,差异有统计学意义(t=9.324、14.682,P<0.05)。实际病灶直径组间差异无统计学意义(P>0.05)。相关性分析显示,在平扫期、动脉期及门脉期图像对比噪声比与测量误差均呈负相关(r=-0.623、-0.714、-0.687,P<0.01),信噪比与测量误差在各期间同样呈负相关关系(r=-0.581、-0.698、-0.652,P<0.01),动脉期对比噪声比的负相关性最强(r=-0.714)。结论:呼吸运动补偿算法的改良通过提升时间分辨率和优化重建参数,显著改善肝右叶病灶CT图像的客观质量与主观评分,并有效降低测量误差,其强负相关性提示动脉期图像质量优化对精准诊疗尤为关键。 展开更多
关键词 呼吸运动补偿算法 肝右叶病灶 ct图像质量 测量误差 图像重建 运动伪影
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AI算法分析后交叉韧带胫骨撕脱骨折CT三维图像诊断及精准评估
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作者 成永忠 李锐 +3 位作者 罗想利 王璠 陈洋 闫威 《中国组织工程研究》 北大核心 2026年第21期5589-5596,共8页
背景:后交叉韧带附着点撕脱骨折的手术决策高度依赖影像学评估,传统方法依赖CT影像进行主观判读,存在三维空间位移参数量化困难、旋转角度评估精度不足等局限,鉴于AI技术的发展,有必要开发基于AI算法的自动化、智能化影像识别软件。目的... 背景:后交叉韧带附着点撕脱骨折的手术决策高度依赖影像学评估,传统方法依赖CT影像进行主观判读,存在三维空间位移参数量化困难、旋转角度评估精度不足等局限,鉴于AI技术的发展,有必要开发基于AI算法的自动化、智能化影像识别软件。目的:探讨AI算法在CT三维图像中对后交叉韧带胫骨撕脱骨折的智能诊断能力及其对骨折块三维参数的精准评估效能。方法:回顾性纳入2022-12-01/2024-08-30在中国中医科学院望京医院就诊的24例后交叉韧带胫骨撕脱骨折患者的膝关节CT数据,使用自主研发的AI影像识别软件进行三维重建、骨折点智能识别及模拟复位,获取骨折块在X、Y、Z轴上的平移和旋转参数。与传统放射阅片软件(PACS系统)测量结果进行对比,采用秩和检验、Bland-Altman分析及线性回归模型评估两种方法的一致性,并计算变异系数验证软件稳定性。结果与结论:①AI软件与传统方法测量的骨折块位移(X/Y/Z轴平移及旋转)差异均无显著性意义(P>0.05);②Bland-Altman分析显示两种方法一致性良好,差异均无显著性意义(P>0.05);③X、Y、Z轴位移、角度两组拟合情况线性回归模型R^(2)值均>0.99;④AI软件重复3次骨折点识别的变异系数显示:总骨折识别时21例影像资料的变异系数<20%,识别关节面骨折点时18例变异系数<20%;⑤表明AI影像识别软件可精准量化后交叉韧带撕脱骨折块的三维参数,其测量结果与传统方法一致且稳定性良好,可辅助医生判断移位程度,为术前规划提供精准数据支持;该软件在撕脱骨折中有良好的应用前景,未来需扩大样本量并进一步验证其对手术疗效的影响。 展开更多
关键词 后交叉韧带撕脱骨折 人工智能 ct影像识别 三维测量 术前规划
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精细化护理在增强CT造影剂外渗护理中的应用效果观察
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作者 赵春生 赵立森 +1 位作者 彭双双 黄国芳 《首都食品与医药》 2026年第2期103-106,共4页
目的分析精细化护理在增强CT造影剂外渗护理中的应用效果。方法选取首都医科大学附属北京胸科医院2023年11月-2024年11月患者68例,随机分为两组,每组34例,对照组予以常规护理,观察组予以精细化护理,对比其护理效果。结果观察组并发症发... 目的分析精细化护理在增强CT造影剂外渗护理中的应用效果。方法选取首都医科大学附属北京胸科医院2023年11月-2024年11月患者68例,随机分为两组,每组34例,对照组予以常规护理,观察组予以精细化护理,对比其护理效果。结果观察组并发症发生率低于对照组;消极情绪评分低于对照组;护理满意度高于对照组;护理质量高于对照组(P<0.05)。结论在增强CT造影剂外渗中实行精细化护理,其临床价值显著,可有效提升护理质量,并改善患者消极情绪,值得推广。 展开更多
关键词 精细化护理 增强ct 造影剂 外渗 应用效果
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基于胰腺CT评估不同糖耐量受损人群胰腺脂肪成分占比及与胰岛功能相关性
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作者 张梦琪 李晶晶 +1 位作者 刘烁 陈杰 《中国CT和MRI杂志》 2026年第2期108-111,共4页
目的基于胰腺CT评估不同糖耐量受损人群胰腺脂肪成分占比及其与胰岛功能相关性。方法选取本院178例接受口服葡萄糖耐量试验(OGTT)的糖耐量受损者作为研究对象,根据糖耐量受损情况,分为4组:空腹血糖受损(IFG)组、糖耐量减低(IGT)组、IFG+... 目的基于胰腺CT评估不同糖耐量受损人群胰腺脂肪成分占比及其与胰岛功能相关性。方法选取本院178例接受口服葡萄糖耐量试验(OGTT)的糖耐量受损者作为研究对象,根据糖耐量受损情况,分为4组:空腹血糖受损(IFG)组、糖耐量减低(IGT)组、IFG+IGT组与新诊断2型糖尿病(T2DM)组,使用胰腺CT评估胰腺脂肪成分占比,分析胰腺脂肪成分占比与胰岛功能[空腹胰岛素(FINS)、饭后2h胰岛素(2h INS)、β细胞功能指数(HOMA-β)、胰岛素抵抗指数(HOMA-IR)]的相关性。结果胰腺脂肪脂肪成分占比为:T2DM组(19.72±3.50)%>IFG+IGT组(16.09±3.14)%>IFG组(11.42±2.38)%>IGT组(9.98±1.85)%,差异有统计学意义(P<0.05);FINS与2h INS:T2DM组[(32.02±5.73)μU/mL、(116.79±17.82)μU/m L]>IGT组[(27.74±4.20)μU/mL、(93.78±15.35)μU/mL]与IFG+IGT组[(27.81±4.25)μU/mL、(93.29±16.54)μU/mL]>IFG组[(3.19±0.83)μU/mL、(23.16±5.08)μU/mL],差异有统计学意义(P<0.05);HOMA-β:IGT组(64.56±8.60)%>IFG组(43.71±5.54)%与IFG+IGT组(42.69±5.56)%>T2DM组(33.39±7.48)%,差异有统计学意义(P<0.05);HOMA-IR:T2DM组(1.25±0.26)>IFG+IGT组(0.91±0.16)>IFG组(0.69±0.12)>IGT组(0.31±0.08),差异有统计学意义(P<0.05);FINS、2h INS、HOMA-IR与胰腺脂肪成分占比呈正相关(r=0.345、0.459、0.689,P<0.05),HOMA-β与胰腺脂肪成分占比呈负相关(r=-0.576,P<0.05)。结论IFG、IFG+IGT、T2DM人群胰腺脂肪成分占比逐渐升高,且与FINS、2hINS、HOMA-IR、HOMA-β密切相关。 展开更多
关键词 糖耐量受损 胰腺 脂肪 ct 胰岛功能
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术前CT小肠成像对克罗恩病炎症活动度及初次肠切除术后早期吻合口复发的预测价值
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作者 李冬雪 詹志勇 +2 位作者 李超 于兰英 王洋 《川北医学院学报》 2026年第1期89-93,共5页
目的:探讨术前CT小肠成像(CTE)对克罗恩病(CD)炎症活动度及初次肠切除术后早期吻合口复发(EAR)的预测价值。方法:选取70例行初次肠切除的CD患者为研究对象,依据炎症活动度分为活动期组(n=42)和缓解期组(n=28);依据术后6个月内发生EAR与... 目的:探讨术前CT小肠成像(CTE)对克罗恩病(CD)炎症活动度及初次肠切除术后早期吻合口复发(EAR)的预测价值。方法:选取70例行初次肠切除的CD患者为研究对象,依据炎症活动度分为活动期组(n=42)和缓解期组(n=28);依据术后6个月内发生EAR与否分复发组(n=16)和未复发组(n=54)。比较不同炎症活动度组、复发与未复发组的临床特征、CTE征象及CD简化内镜(SES-CD)评分;受试者工作特征(ROC)曲线分析CTE征象对CD炎症活动度及初次肠切除术后EAR的预测价值。结果:活动期组患者肠壁厚度、肠黏膜静脉期CT值、ΔCT值、肠腔狭窄率、肠系膜淋巴结肿大率、肠系膜纤维脂肪增生率、梳状征率、脓肿/瘘管率及肠壁分层强化分型A型与B型概率高于缓解期组,差异均有统计学意义(P<0.05)。复发组患者肠壁厚度、肠黏膜静脉期CT值、ΔCT值、肠系膜淋巴结肿大率、肠系膜纤维脂肪增生率、脓肿/瘘管率高于未复发组,差异均有统计学意义(P<0.05)。受试者工作特征曲线(ROC)曲线分析显示,CTE征象联合预测CD炎症活动度的曲线下面积(AUC)为0.967;预测术后EAR的AUC为0.977,均高于单个征象预测的AUC(P<0.05)。结论:术前CTE各征象联合评估对CD患者炎症活动度及初次肠切除后术后EAR均有较好的预测价值。 展开更多
关键词 ct小肠成像 克罗恩病 炎症活动度 肠切除术 早期吻合口复发
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CT结合DR乳腺钼靶X线诊断乳腺良恶性病变的价值分析
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作者 谭延召 徐红卫 +1 位作者 梁盼 夏燕娜 《中国CT和MRI杂志》 2026年第2期97-100,共4页
目的探析CT结合数字化(DR)乳腺钼靶X线成像技术(DBT)诊断乳腺良恶性病变的价值。方法对2022年12月至2023年12月我院收治的80例乳腺病变患者的临床资料进行回顾性分析,所有患者均行CT、DBT及病理学检查,以病理结果为金标准,分析不同检查... 目的探析CT结合数字化(DR)乳腺钼靶X线成像技术(DBT)诊断乳腺良恶性病变的价值。方法对2022年12月至2023年12月我院收治的80例乳腺病变患者的临床资料进行回顾性分析,所有患者均行CT、DBT及病理学检查,以病理结果为金标准,分析不同检查方法诊鉴别诊断乳腺良恶性病变的价值。结果80例患者经病理确诊为良性病变42例(52.50%),恶性病变者38例(47.50%);良性组和恶性组在CT、DBT各检查中的影像学特征对比,差异均有统计学意义(P<0.05);CT、DBT单独及联合检测诊断乳腺良恶性病变与病理检查的Kappa值分别为0.474、0.424、0.800(P<0.05),二者联合的灵敏性、准确率均高于上述方式单独检测(P<0.05)。结论CT结合DBT在乳腺良恶性病变诊断中具有一定的价值,其病灶形态、边缘、钙化灶分布等影像学征象可为疾病的鉴别诊断提供丰富的依据。 展开更多
关键词 乳腺病变 ct 乳腺钼靶数字化X线成像技术 鉴别诊断 价值
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