BACKGROUND Photon-counting detector(PCD)CT represents a transformative advancement in radiological imaging,offering superior spatial resolution,enhanced contrast-tonoise ratio,and reduced radiation dose compared with ...BACKGROUND Photon-counting detector(PCD)CT represents a transformative advancement in radiological imaging,offering superior spatial resolution,enhanced contrast-tonoise ratio,and reduced radiation dose compared with the conventional energyintegrating detector CT.AIM To evaluate PCD CT in oncologic imaging,focusing on its role in tumor detection,staging,and treatment response assessment.METHODS We performed a systematic PubMed search from January 1,2017 to December 31,2024,using the keywords“photon-counting CT”,“cancer”,and“tumor”to identify studies on its use in oncologic imaging.We included experimental studies on humans or human phantoms and excluded reviews,commentaries,editorials,non-English,animal,and non-experimental studies.Study selection followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Out of 175 initial studies,39 met the inclusion criteria after screening and full-text review.Data extraction focused on study type,country of origin,and oncologic applications of photon-counting CT.No formal risk of bias assessment was performed,and the review was not registered in PROSPERO as it did not include a meta-analysis.RESULTS Key findings highlighted the advantages of PCD CT in imaging renal masses,adrenal adenomas,ovarian cancer,breast cancer,prostate cancer,pancreatic tumors,hepatocellular carcinoma,metastases,multiple myeloma,and lung cancer.Additionally,PCD CT has demonstrated improved lesion characterization and enhanced diagnostic accuracy in oncology.Despite its promising capabilities challenges related to data processing,storage,and accessibility remain.CONCLUSION As PCD CT technology evolves,its integration into routine oncologic imaging has the potential to significantly enhance cancer diagnosis and patient management.展开更多
Spectral computed tomography(CT)imaging as an advanced and non-invasive technique is of importance in the diagnosis of disease.Therefore,it is significant to develop safe and high-performance contrast agents for spect...Spectral computed tomography(CT)imaging as an advanced and non-invasive technique is of importance in the diagnosis of disease.Therefore,it is significant to develop safe and high-performance contrast agents for spectral CT imaging.Herein,we synthesized a small-molecule erbium chelate(ErDOTA dimeglumine),with the advantages of favorable colloidal and structure stability,good biocompatibility and biosafety,and sensitive spectral CT imaging ability in vitro and in vivo.Erbium chelate exhibits strong X-ray attenuation capability and the energy-dependent attenuation in the range of 40-160 keV due to the high K-edge value of Er(57.5 keV).Especially,the slope of the Hounsfield unit(HU)curve for erbium chelate is 1.5 times that of iohexol at 50 keV,and 5.6 times that of iohexol at130 keV.We then applied erbium chelate in the in vivo spectral CT imaging of healthy mice and DSSinduced colitis mice.It is found that erbium chelate is rapidly metabolized from the intestinal tract in healthy mice within 12 h due to favorable biocompatibility,while it is enriched and displays brighter signals in the inflammatory site of colon in colitis mice.Specifically,the CT value in the large intestines of colitis mice 12 h after erbium chelate administration is 53.0,which is much higher than that of healthy mice(8.3),showing great potential for sensitive and accurate diagnosis of inflammatory bowel disease.Moreover,compared with the clinically used contrast agent iohexol,erbium chelate shows better spectral CT imaging performance in both healthy and colitis mice at low to high energy settings.Superior CT imaging is also observed in CT26 tumor-bearing mice after administration with erbium chelate in comparison to iohexol.In summary,the small-molecule erbium chelate is expected to be a safe and highperfo rmance co ntrast agent for spectral CT imaging to promote the diagnosis of gastrointestinal diseases.展开更多
This study aims to explore the clinical and CT imaging features of brucellosis spondylitis(BS)and to strengthen the clinical cognition to reduce misdiagnosis and mistreatment.In this study,clinical and CT imaging data...This study aims to explore the clinical and CT imaging features of brucellosis spondylitis(BS)and to strengthen the clinical cognition to reduce misdiagnosis and mistreatment.In this study,clinical and CT imaging data of 106 patients with BS diagnosed in the Second Hospital of Hohhot and the Third Hospital of Baotou were collected from March 2023 to September 2024 and retrospectively analyzed by clinical manifestations,CT imaging,and disease regression.In 106 patients,58.5%had fever,98.1%had malaise,96.2%had excessive sweating,81.1%had lumbosacral pain,79.3%had limitation of limb movement,76.4%had constipation,and 6.6%had urinary retention.For imaging manifestations,the involvement of lumbar,thoracic and cervical vertebrae were 80.2%,16.9%and 1.9%,respectively.Lesions<1.0 cm,1.0–2.0 cm,2.0–3.0 cm,and>3.0 cm were found in 49.4%,29.6%,19.4%,and 1.6%,respectively.In 106 patients,CT showed round,irregular or worm-like areas of bone destruction,with coexisting osteophytes in 61.5%and no signs of dead bone or pedicle destruction.Interdiscal destruction,spinal canal abscess,ligament injury,and signs of lumbar major muscle compression were rare,accounting for 11.7%,6.6%,4.7%,and 3.8%,respectively.Regarding regression,106 patients with BS treated with antimicrobial therapy or antimicrobial+surgery had a good prognosis.In conclusion,BS has its own characteristics in clinical and imaging aspects and it is easy to distinguish from other common causes of spondylitis bone damage.展开更多
Artificial intelligence(AI)is rapidly transforming radiology and computed tomography(CT)imaging by enabling automated image analysis,improved diagnostic accuracy,and clinical decision-support.We performed a systematic...Artificial intelligence(AI)is rapidly transforming radiology and computed tomography(CT)imaging by enabling automated image analysis,improved diagnostic accuracy,and clinical decision-support.We performed a systematic review of peerreviewed studies published between January 1,2010 and March 31,2025 to quantify reported gains in diagnostic performance and workflow efficiency,to evaluate clinical decision-support benefits and risks,and to identify integration priorities.We searched PubMed,IEEE Xplore,Scopus,ScienceDirect,and Google Scholar and screened 128 records;26 studies met the inclusion criteria.Extracted data included study design,AI architecture,sample size,and quantitative performance metrics;study quality was assessed using Newcastle-Ottawa Scales(NOS),Cochrane RoB 2,or AMSTAR 2 as appropriate.Across included studies,AI applications in CT showed consistent improvements in sensitivity,specificity,and time-to-diagnosis in specific tasks(notably lung-nodule detection and intracranial hemorrhage triage),with reported detection-rate increases up to~20%and reduced turnaround times in several real-world implementations.Barriers include dataset bias,limited external validation,interpretability(“black-box”)concerns,workflow integration challenges,and evolving regulatory issues.Economic analyses suggest potentially favorable return on investment(ROI)in high-volume settings but are sensitive to licensing and infrastructure costs.To realize AI's benefits in CT imaging,rigorous multi-center validation,transparent reporting,humancentered workflow design,and post-deployment surveillance are essential.展开更多
Photodynamic therapy(PDT),as a non-invasive treatment,is expected to be widely used in clinical cancer treatment.In this paper,a near-infrared(NIR)light responsive Lu_(2)O_(3):Yb/Er/Li-Ce6@MIL-101/GOx-PDA(LCMGP)nanodi...Photodynamic therapy(PDT),as a non-invasive treatment,is expected to be widely used in clinical cancer treatment.In this paper,a near-infrared(NIR)light responsive Lu_(2)O_(3):Yb/Er/Li-Ce6@MIL-101/GOx-PDA(LCMGP)nanodiagnostic platform was prepared for CT/PA imaging-guided multimodality synergistic therapy.Under 808 nm laser irradiation,Lu_(2)O_(3):Yb/Er/Li-Ce6(LC)NPs in the nano-diagnostic platform are activated and sensitized by NIR light,resulting in the generation of more single-linear oxygen(^(1)O_(2))for efficient PDT.Glucose oxidase(GOx)and MIL-101(Fe)nanozymes can utilize their excellent enzyme cascade catalytic properties and peroxidase-like catalytic properties to undergo glycolysis reactions and catalyze the decomposition of endogenous hydrogen peroxide(H_(2)O_(2)),producing a large amount of hydroxyl radicals(·OH),achieving efficient chemodynamic therapy(CDT).The functionalized modification of polydopamine(PDA)endows the LCMGP nanoparticles with higher photothermal conversion efficiency,which can prompt high local temperature at the tumor site under the irradiation of NIR light to achieve efficient photothermal therapy(PTT).In addition,hyperthermia accelerates the catalytic efficiency of the nanozymatic cascade of LCMGP nanoparticles to enhance ROS production while increasing cellular uptake,resulting in PTT-induced PDT/CDT synergistic effect(96%).Based on the excellent photothermal conversion effect of PDA and the high X-ray atte nuation effect of Lu/Fe,the LCMGP nanotherapeutic system demonstrates good CT/PA imaging function,providing new insights and ideas for imaging-mediated multimodal synergistic therapy.展开更多
Breast cancer(BC)is currently the most common malignancy worldwide and the leading cause of cancer-related death in women.1 At the molecular level,breast cancer is highly heterogeneous,with multiple subtypes,including...Breast cancer(BC)is currently the most common malignancy worldwide and the leading cause of cancer-related death in women.1 At the molecular level,breast cancer is highly heterogeneous,with multiple subtypes,including human epidermal growth factor receptor-2-positive,luminal A,luminal B,and triple-negative breast cancer(TNBC),each requiring different clinical treatment approaches.2,3 Among breast cancer patients,70%-80%are estrogen receptor-positive(ER^(+)).4 TNBC is the most aggressive type and is characterized by a poor prognosis and a high risk of death.5 Epidemiological data indicate that TNBC mainly occurs in young premenopausal women under 40 years of age,accounting for approximately 15%-20%of all breast cancer patients.Compared with patients with other subtypes of breast cancer,TNBC patients have shorter survival times,6 with a 40%mortality rate within 5 years of post-diagnosis.7 Therefore,early diagnosis and treatment are vital for improving outcomes in breast cancer patients.Positron emission tomography/computed tomography(PET/CT)using fluorine-18-2-fluoro-2-deoxy-glucose(^(18)F-FDG)is the most commonly used tracer in the clinic and has been used for breast cancer imaging.However,its use in detection,differential diagnosis of benign versus malignant lesions,and local tumor staging in breast cancer is not recommended.This is due to its high false-negative rate for detecting small tumors(<1 cm)and low-grade breast cancers and a high false-positive rate for local benign breast conditions.8 These limitations have driven the exploration of novel targets for PET radiotracers.The development of new PET radiotracers holds the potential for significantly advancing the diagnosis,staging,management,and treatment of breast cancer in the future.展开更多
Imaging technologies are utilized to study the brain morphology and the functions of rat models of Parkinson disease （PD）. Magnetic resonance imaging （MRI） and magnetic resonance angiography （MRA） are used to ob...Imaging technologies are utilized to study the brain morphology and the functions of rat models of Parkinson disease （PD）. Magnetic resonance imaging （MRI） and magnetic resonance angiography （MRA） are used to obtain morphological imaging data. Functional imaging data, such as the spectrum and blood flow changes are obtained by proton magnetic resonance spectroscopy （1H-MRS） and CT perfusion （CTP）. Results show that PD rat models have no characteristic morphological imaging abnormalities, but exist regional cerebral blood flow （CBF） reductions and spectral changes in the striatum.展开更多
目的构建并验证基于CT及灌注特征的分级预测模型,评估其对急性缺血性卒中血管内治疗后神经功能改善的预测价值。方法回顾性分析2019年1月至2024年3月重庆医科大学附属永川医院收治的183例接受机械取栓治疗的缺血性卒中患者的临床资料。...目的构建并验证基于CT及灌注特征的分级预测模型,评估其对急性缺血性卒中血管内治疗后神经功能改善的预测价值。方法回顾性分析2019年1月至2024年3月重庆医科大学附属永川医院收治的183例接受机械取栓治疗的缺血性卒中患者的临床资料。根据6个月mRS评分将患者分为未改善组(n=44)和改善组(n=139)。收集临床资料、CT平扫及CTP参数,构建6个创新性综合指标,包括早期神经功能严重程度指数(ENSI)、灌注-核心不匹配指数(PCMI)等。采用分级建模策略构建基础模型(临床变量)、增强模型(+CT形态学)和综合模型(+CTP及创新性变量),通过受试者工作特征(ROC)曲线、净重分类改善指数(NRI)和综合判别改善指数(IDI)评估模型性能。结果未改善组患者的基线NIHSS评分[(18.45±5.68)分vs(12.41±5.70)分]、血糖水平[(8.76±4.68)mmol/L vs(6.70±2.25)mmol/L]和核心梗死体积[20.28(1.92~67.59)mL vs 3.68(0.86~11.80)mL]均明显高于改善组,差异均有统计学意义(P<0.01)。多因素分析结果显示,基线NIHSS(OR=1.231,P<0.001)、血糖(OR=1.285,P=0.001)、核心梗死体积(OR=1.016,P=0.037)和ENSI(OR=0.831,P=0.006)是独立预测因子。综合模型AUC值(0.855)优于增强模型(0.830)和基础模型(0.825)。相对于增强模型,综合模型NRI达0.677,IDI为0.091。结论整合CTP参数和创新性综合指标的分级预测模型可有效预测缺血性卒中血管内治疗后神经功能改善。ENSI作为独立预测因子,计算简便,具有良好的临床应用前景。展开更多
Thirty-four patients with cerebral infarction and 18 patients with transient ischemic attack were examined by multi-slice spiral CT scan, CT perfusion imaging, and CT angiography within 6 hours after onset. By CT perf...Thirty-four patients with cerebral infarction and 18 patients with transient ischemic attack were examined by multi-slice spiral CT scan, CT perfusion imaging, and CT angiography within 6 hours after onset. By CT perfusion imaging, 29 cases in the cerebral infarction group and 10 cases in the transient ischemic attack group presented with abnormal blood flow perfusion, which corresponded to the clinical symptoms. By CT angiography, various degrees of vascular stenosis could be detected in 41 patients, including 33 in the cerebral infarction group and eight in the transient ischemic attack group. The incidence of intracranial artery stenosis was higher than that of extracranial artery stenosis. The intracranial artery stenosis was located predominantly in the middle cerebral artery and carotid artery siphon, while the extracranial artery stenosis occurred mainly in the bifurcation of the common carotid artery and the opening of the vertebral artery. There were 34 cases （83%） with convict vascular stenosis and perfusion abnormalities, and five cases （45%） with perfusion abnormalities but without convict vascular stenosis. The incidence of cerebral infarction in patients with National Institutes of Health Stroke Scale scores 〉 5 points during onset was significantly higher than that in patients with National Institutes of Health Stroke Scale scores 〈 5 points. These experimental findings indicate that the combined application of various CT imaging methods allows early diagnosis of acute ischemic cerebrovascular disease, which can comprehensively analyze the pathogenesis and severity of acute ischemic cerebrovascular disease at the morphological and functional levels.展开更多
Objective： To explore whether single and fused monochromatic images can improve liver tumor detection and delineation by single source dual energy CT （ssDECT） in patients with hepatocellular carcinoma （HCC） durin...Objective： To explore whether single and fused monochromatic images can improve liver tumor detection and delineation by single source dual energy CT （ssDECT） in patients with hepatocellular carcinoma （HCC） during arterial phase. Methods： Fifty-seven patients with HCC who underwent ssDECT scanning at Beijing Cancer Hospital were enrolled retrospectively. Twenty-one sets of monochromatic images from 40 to 140 keV were reconstructed at 5 keV intervals in arterial phase. The optimal contrast-noise ratio （CNR） monochromatic images of the liver tumor and the lowest-noise monochromatic images were selected for image fusion. We evaluated the image quality of the optimal-CNR monochromatic images, the lowest-noise monochromatic images and the fused monochromatic images, respectively. The evaluation indicators included the spatial resolution of the anatomical structure, the noise level, the contrast and CNR of the tumor. Results： In arterial phase, the anatomical structure of the liver can be displayed most clearly in the 65-keV monochromatic images, with the lowest image noise. The optimal-CNR monochromatic images of HCC tumor were 50-keV monochromatic images in which the internal structural features of the liver tumors were displayed most clearly and meticulously. For tumor detection, the fused monochromatic images and the 50-keV monochromatic images had similar performances, and were more sensitive than 65-keV monochromatic images. Conclusions： We achieved good arterial phase images by fusing the optimal-CNR monochromatic images of the HCC tumor and the lowest-noise monochromatic images. The fused images displayed liver tumors and anatomical structures more clearly, which is potentially helpful for identifying more and smaller HCC tumors.展开更多
Spectral computed tomography(CT) based on photon counting detectors(PCDs) is a well-researched topic in the field of X-ray imaging. When PCD is applied in a spectral CT system, the PCD energy thresholds must be carefu...Spectral computed tomography(CT) based on photon counting detectors(PCDs) is a well-researched topic in the field of X-ray imaging. When PCD is applied in a spectral CT system, the PCD energy thresholds must be carefully selected, especially for K-edge imaging, which is an important spectral CT application. This paper presents a threshold selection method that yields better-quality images in K-edge imaging. The main idea is to optimize the energy thresholds ray-by-ray according to the targeted component coefficients, followed by obtaining an overall optimal energy threshold by frequency voting. A low-dose pre-scan is used in practical implementations to estimate the line integrals of the component coefficients for the basis functions. The variance of the decomposed component coefficients is then minimized using the Cramer–Rao lower bound method with respect to the energy thresholds. The optimal energy thresholds are then used to take a full scan and gain better image reconstruction with less noise than would be given by a full scan using the non-optimal energy thresholds. Simulations and practical experiments on imaging iodine and gadolinium solutions, which are commonly used as contrast agents in medical applications, were used to validate the method. The noise was significantly reduced with the same dose relative to the non-optimal energy thresholds in both simulations and in practical experiments.展开更多
文摘BACKGROUND Photon-counting detector(PCD)CT represents a transformative advancement in radiological imaging,offering superior spatial resolution,enhanced contrast-tonoise ratio,and reduced radiation dose compared with the conventional energyintegrating detector CT.AIM To evaluate PCD CT in oncologic imaging,focusing on its role in tumor detection,staging,and treatment response assessment.METHODS We performed a systematic PubMed search from January 1,2017 to December 31,2024,using the keywords“photon-counting CT”,“cancer”,and“tumor”to identify studies on its use in oncologic imaging.We included experimental studies on humans or human phantoms and excluded reviews,commentaries,editorials,non-English,animal,and non-experimental studies.Study selection followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Out of 175 initial studies,39 met the inclusion criteria after screening and full-text review.Data extraction focused on study type,country of origin,and oncologic applications of photon-counting CT.No formal risk of bias assessment was performed,and the review was not registered in PROSPERO as it did not include a meta-analysis.RESULTS Key findings highlighted the advantages of PCD CT in imaging renal masses,adrenal adenomas,ovarian cancer,breast cancer,prostate cancer,pancreatic tumors,hepatocellular carcinoma,metastases,multiple myeloma,and lung cancer.Additionally,PCD CT has demonstrated improved lesion characterization and enhanced diagnostic accuracy in oncology.Despite its promising capabilities challenges related to data processing,storage,and accessibility remain.CONCLUSION As PCD CT technology evolves,its integration into routine oncologic imaging has the potential to significantly enhance cancer diagnosis and patient management.
基金Project supported by the National Natural Science Foundation of China(82304311,81903460)the Sichuan Province Science and Technology Program(2022YFS0616)。
文摘Spectral computed tomography(CT)imaging as an advanced and non-invasive technique is of importance in the diagnosis of disease.Therefore,it is significant to develop safe and high-performance contrast agents for spectral CT imaging.Herein,we synthesized a small-molecule erbium chelate(ErDOTA dimeglumine),with the advantages of favorable colloidal and structure stability,good biocompatibility and biosafety,and sensitive spectral CT imaging ability in vitro and in vivo.Erbium chelate exhibits strong X-ray attenuation capability and the energy-dependent attenuation in the range of 40-160 keV due to the high K-edge value of Er(57.5 keV).Especially,the slope of the Hounsfield unit(HU)curve for erbium chelate is 1.5 times that of iohexol at 50 keV,and 5.6 times that of iohexol at130 keV.We then applied erbium chelate in the in vivo spectral CT imaging of healthy mice and DSSinduced colitis mice.It is found that erbium chelate is rapidly metabolized from the intestinal tract in healthy mice within 12 h due to favorable biocompatibility,while it is enriched and displays brighter signals in the inflammatory site of colon in colitis mice.Specifically,the CT value in the large intestines of colitis mice 12 h after erbium chelate administration is 53.0,which is much higher than that of healthy mice(8.3),showing great potential for sensitive and accurate diagnosis of inflammatory bowel disease.Moreover,compared with the clinically used contrast agent iohexol,erbium chelate shows better spectral CT imaging performance in both healthy and colitis mice at low to high energy settings.Superior CT imaging is also observed in CT26 tumor-bearing mice after administration with erbium chelate in comparison to iohexol.In summary,the small-molecule erbium chelate is expected to be a safe and highperfo rmance co ntrast agent for spectral CT imaging to promote the diagnosis of gastrointestinal diseases.
文摘This study aims to explore the clinical and CT imaging features of brucellosis spondylitis(BS)and to strengthen the clinical cognition to reduce misdiagnosis and mistreatment.In this study,clinical and CT imaging data of 106 patients with BS diagnosed in the Second Hospital of Hohhot and the Third Hospital of Baotou were collected from March 2023 to September 2024 and retrospectively analyzed by clinical manifestations,CT imaging,and disease regression.In 106 patients,58.5%had fever,98.1%had malaise,96.2%had excessive sweating,81.1%had lumbosacral pain,79.3%had limitation of limb movement,76.4%had constipation,and 6.6%had urinary retention.For imaging manifestations,the involvement of lumbar,thoracic and cervical vertebrae were 80.2%,16.9%and 1.9%,respectively.Lesions<1.0 cm,1.0–2.0 cm,2.0–3.0 cm,and>3.0 cm were found in 49.4%,29.6%,19.4%,and 1.6%,respectively.In 106 patients,CT showed round,irregular or worm-like areas of bone destruction,with coexisting osteophytes in 61.5%and no signs of dead bone or pedicle destruction.Interdiscal destruction,spinal canal abscess,ligament injury,and signs of lumbar major muscle compression were rare,accounting for 11.7%,6.6%,4.7%,and 3.8%,respectively.Regarding regression,106 patients with BS treated with antimicrobial therapy or antimicrobial+surgery had a good prognosis.In conclusion,BS has its own characteristics in clinical and imaging aspects and it is easy to distinguish from other common causes of spondylitis bone damage.
文摘Artificial intelligence(AI)is rapidly transforming radiology and computed tomography(CT)imaging by enabling automated image analysis,improved diagnostic accuracy,and clinical decision-support.We performed a systematic review of peerreviewed studies published between January 1,2010 and March 31,2025 to quantify reported gains in diagnostic performance and workflow efficiency,to evaluate clinical decision-support benefits and risks,and to identify integration priorities.We searched PubMed,IEEE Xplore,Scopus,ScienceDirect,and Google Scholar and screened 128 records;26 studies met the inclusion criteria.Extracted data included study design,AI architecture,sample size,and quantitative performance metrics;study quality was assessed using Newcastle-Ottawa Scales(NOS),Cochrane RoB 2,or AMSTAR 2 as appropriate.Across included studies,AI applications in CT showed consistent improvements in sensitivity,specificity,and time-to-diagnosis in specific tasks(notably lung-nodule detection and intracranial hemorrhage triage),with reported detection-rate increases up to~20%and reduced turnaround times in several real-world implementations.Barriers include dataset bias,limited external validation,interpretability(“black-box”)concerns,workflow integration challenges,and evolving regulatory issues.Economic analyses suggest potentially favorable return on investment(ROI)in high-volume settings but are sensitive to licensing and infrastructure costs.To realize AI's benefits in CT imaging,rigorous multi-center validation,transparent reporting,humancentered workflow design,and post-deployment surveillance are essential.
基金Project supported by the Natural Science Foundation of Shandong Province(ZR2020ME045,ZR2020ME046)the Taishan Scholar Project of Shandong Province(tsqn201812130)+2 种基金the National Natural Science Foundation of China(82272833)"New Universities 20"Foundation of Jinan(2021GXRC099,T202204)China Postdoctoral Science Foundation(2022M711438)。
文摘Photodynamic therapy(PDT),as a non-invasive treatment,is expected to be widely used in clinical cancer treatment.In this paper,a near-infrared(NIR)light responsive Lu_(2)O_(3):Yb/Er/Li-Ce6@MIL-101/GOx-PDA(LCMGP)nanodiagnostic platform was prepared for CT/PA imaging-guided multimodality synergistic therapy.Under 808 nm laser irradiation,Lu_(2)O_(3):Yb/Er/Li-Ce6(LC)NPs in the nano-diagnostic platform are activated and sensitized by NIR light,resulting in the generation of more single-linear oxygen(^(1)O_(2))for efficient PDT.Glucose oxidase(GOx)and MIL-101(Fe)nanozymes can utilize their excellent enzyme cascade catalytic properties and peroxidase-like catalytic properties to undergo glycolysis reactions and catalyze the decomposition of endogenous hydrogen peroxide(H_(2)O_(2)),producing a large amount of hydroxyl radicals(·OH),achieving efficient chemodynamic therapy(CDT).The functionalized modification of polydopamine(PDA)endows the LCMGP nanoparticles with higher photothermal conversion efficiency,which can prompt high local temperature at the tumor site under the irradiation of NIR light to achieve efficient photothermal therapy(PTT).In addition,hyperthermia accelerates the catalytic efficiency of the nanozymatic cascade of LCMGP nanoparticles to enhance ROS production while increasing cellular uptake,resulting in PTT-induced PDT/CDT synergistic effect(96%).Based on the excellent photothermal conversion effect of PDA and the high X-ray atte nuation effect of Lu/Fe,the LCMGP nanotherapeutic system demonstrates good CT/PA imaging function,providing new insights and ideas for imaging-mediated multimodal synergistic therapy.
基金support of the Department of Nuclear Medicine,Peking University Cancer Hospital。
文摘Breast cancer(BC)is currently the most common malignancy worldwide and the leading cause of cancer-related death in women.1 At the molecular level,breast cancer is highly heterogeneous,with multiple subtypes,including human epidermal growth factor receptor-2-positive,luminal A,luminal B,and triple-negative breast cancer(TNBC),each requiring different clinical treatment approaches.2,3 Among breast cancer patients,70%-80%are estrogen receptor-positive(ER^(+)).4 TNBC is the most aggressive type and is characterized by a poor prognosis and a high risk of death.5 Epidemiological data indicate that TNBC mainly occurs in young premenopausal women under 40 years of age,accounting for approximately 15%-20%of all breast cancer patients.Compared with patients with other subtypes of breast cancer,TNBC patients have shorter survival times,6 with a 40%mortality rate within 5 years of post-diagnosis.7 Therefore,early diagnosis and treatment are vital for improving outcomes in breast cancer patients.Positron emission tomography/computed tomography(PET/CT)using fluorine-18-2-fluoro-2-deoxy-glucose(^(18)F-FDG)is the most commonly used tracer in the clinic and has been used for breast cancer imaging.However,its use in detection,differential diagnosis of benign versus malignant lesions,and local tumor staging in breast cancer is not recommended.This is due to its high false-negative rate for detecting small tumors(<1 cm)and low-grade breast cancers and a high false-positive rate for local benign breast conditions.8 These limitations have driven the exploration of novel targets for PET radiotracers.The development of new PET radiotracers holds the potential for significantly advancing the diagnosis,staging,management,and treatment of breast cancer in the future.
基金Supported by the National Natural Science Foundation of China (30671997)~~
文摘Imaging technologies are utilized to study the brain morphology and the functions of rat models of Parkinson disease （PD）. Magnetic resonance imaging （MRI） and magnetic resonance angiography （MRA） are used to obtain morphological imaging data. Functional imaging data, such as the spectrum and blood flow changes are obtained by proton magnetic resonance spectroscopy （1H-MRS） and CT perfusion （CTP）. Results show that PD rat models have no characteristic morphological imaging abnormalities, but exist regional cerebral blood flow （CBF） reductions and spectral changes in the striatum.
文摘目的构建并验证基于CT及灌注特征的分级预测模型,评估其对急性缺血性卒中血管内治疗后神经功能改善的预测价值。方法回顾性分析2019年1月至2024年3月重庆医科大学附属永川医院收治的183例接受机械取栓治疗的缺血性卒中患者的临床资料。根据6个月mRS评分将患者分为未改善组(n=44)和改善组(n=139)。收集临床资料、CT平扫及CTP参数,构建6个创新性综合指标,包括早期神经功能严重程度指数(ENSI)、灌注-核心不匹配指数(PCMI)等。采用分级建模策略构建基础模型(临床变量)、增强模型(+CT形态学)和综合模型(+CTP及创新性变量),通过受试者工作特征(ROC)曲线、净重分类改善指数(NRI)和综合判别改善指数(IDI)评估模型性能。结果未改善组患者的基线NIHSS评分[(18.45±5.68)分vs(12.41±5.70)分]、血糖水平[(8.76±4.68)mmol/L vs(6.70±2.25)mmol/L]和核心梗死体积[20.28(1.92~67.59)mL vs 3.68(0.86~11.80)mL]均明显高于改善组,差异均有统计学意义(P<0.01)。多因素分析结果显示,基线NIHSS(OR=1.231,P<0.001)、血糖(OR=1.285,P=0.001)、核心梗死体积(OR=1.016,P=0.037)和ENSI(OR=0.831,P=0.006)是独立预测因子。综合模型AUC值(0.855)优于增强模型(0.830)和基础模型(0.825)。相对于增强模型,综合模型NRI达0.677,IDI为0.091。结论整合CTP参数和创新性综合指标的分级预测模型可有效预测缺血性卒中血管内治疗后神经功能改善。ENSI作为独立预测因子,计算简便,具有良好的临床应用前景。
基金supported by the Youth Fund of the First Clinical College of Liaoning Medical University, No. 2010C20
文摘Thirty-four patients with cerebral infarction and 18 patients with transient ischemic attack were examined by multi-slice spiral CT scan, CT perfusion imaging, and CT angiography within 6 hours after onset. By CT perfusion imaging, 29 cases in the cerebral infarction group and 10 cases in the transient ischemic attack group presented with abnormal blood flow perfusion, which corresponded to the clinical symptoms. By CT angiography, various degrees of vascular stenosis could be detected in 41 patients, including 33 in the cerebral infarction group and eight in the transient ischemic attack group. The incidence of intracranial artery stenosis was higher than that of extracranial artery stenosis. The intracranial artery stenosis was located predominantly in the middle cerebral artery and carotid artery siphon, while the extracranial artery stenosis occurred mainly in the bifurcation of the common carotid artery and the opening of the vertebral artery. There were 34 cases （83%） with convict vascular stenosis and perfusion abnormalities, and five cases （45%） with perfusion abnormalities but without convict vascular stenosis. The incidence of cerebral infarction in patients with National Institutes of Health Stroke Scale scores 〉 5 points during onset was significantly higher than that in patients with National Institutes of Health Stroke Scale scores 〈 5 points. These experimental findings indicate that the combined application of various CT imaging methods allows early diagnosis of acute ischemic cerebrovascular disease, which can comprehensively analyze the pathogenesis and severity of acute ischemic cerebrovascular disease at the morphological and functional levels.
基金supported by the National Basic Research Program of China (973 Program) (Grant No. 2011CB707705)National Natural Science Foundation of China (Grant No. 81371715+1 种基金 81201215)the Capital Characteristic Clinical Application Research (Grant No. Z121107001012115)
文摘Objective： To explore whether single and fused monochromatic images can improve liver tumor detection and delineation by single source dual energy CT （ssDECT） in patients with hepatocellular carcinoma （HCC） during arterial phase. Methods： Fifty-seven patients with HCC who underwent ssDECT scanning at Beijing Cancer Hospital were enrolled retrospectively. Twenty-one sets of monochromatic images from 40 to 140 keV were reconstructed at 5 keV intervals in arterial phase. The optimal contrast-noise ratio （CNR） monochromatic images of the liver tumor and the lowest-noise monochromatic images were selected for image fusion. We evaluated the image quality of the optimal-CNR monochromatic images, the lowest-noise monochromatic images and the fused monochromatic images, respectively. The evaluation indicators included the spatial resolution of the anatomical structure, the noise level, the contrast and CNR of the tumor. Results： In arterial phase, the anatomical structure of the liver can be displayed most clearly in the 65-keV monochromatic images, with the lowest image noise. The optimal-CNR monochromatic images of HCC tumor were 50-keV monochromatic images in which the internal structural features of the liver tumors were displayed most clearly and meticulously. For tumor detection, the fused monochromatic images and the 50-keV monochromatic images had similar performances, and were more sensitive than 65-keV monochromatic images. Conclusions： We achieved good arterial phase images by fusing the optimal-CNR monochromatic images of the HCC tumor and the lowest-noise monochromatic images. The fused images displayed liver tumors and anatomical structures more clearly, which is potentially helpful for identifying more and smaller HCC tumors.
基金supported by Grants from National key research and development program(No.2016YFF0101304)the National Natural Science Foundation of China(Nos.61771279,11435007)
文摘Spectral computed tomography(CT) based on photon counting detectors(PCDs) is a well-researched topic in the field of X-ray imaging. When PCD is applied in a spectral CT system, the PCD energy thresholds must be carefully selected, especially for K-edge imaging, which is an important spectral CT application. This paper presents a threshold selection method that yields better-quality images in K-edge imaging. The main idea is to optimize the energy thresholds ray-by-ray according to the targeted component coefficients, followed by obtaining an overall optimal energy threshold by frequency voting. A low-dose pre-scan is used in practical implementations to estimate the line integrals of the component coefficients for the basis functions. The variance of the decomposed component coefficients is then minimized using the Cramer–Rao lower bound method with respect to the energy thresholds. The optimal energy thresholds are then used to take a full scan and gain better image reconstruction with less noise than would be given by a full scan using the non-optimal energy thresholds. Simulations and practical experiments on imaging iodine and gadolinium solutions, which are commonly used as contrast agents in medical applications, were used to validate the method. The noise was significantly reduced with the same dose relative to the non-optimal energy thresholds in both simulations and in practical experiments.
