Objective To investigate the image quality, radiation dose and diagnostic value of the low-tube-voltage high-pitch dual-source computed tomography(DSCT) with sinogram affirmed iterative reconstruction(SAFIRE) for non-...Objective To investigate the image quality, radiation dose and diagnostic value of the low-tube-voltage high-pitch dual-source computed tomography(DSCT) with sinogram affirmed iterative reconstruction(SAFIRE) for non-enhanced abdominal and pelvic scans. Methods This institutional review board-approved prospective study included 64 patients who gave written informed consent for additional abdominal and pelvic scan with DSCT in the period from November to December 2012. The patients underwent standard non-enhanced CT scans(protocol 1) [tube voltage of 120 k Vp/pitch of 0.9/filtered back-projection(FBP) reconstruction] followed by high-pitch non-enhanced CT scans(protocol 2)(100 k Vp/3.0/SAFIRE). The total scan time, mean CT number, signal-to-noise ratio(SNR), image quality, lesion detectability and radiation dose were compared between the two protocols. Results The total scan time of protocol 2 was significantly shorter than that of protocol 1(1.4±0.1 seconds vs. 7.6±0.6 seconds, P<0.001). There was no significant difference between protocol 1 and protocol 2 in mean CT number of all organs(liver, 55.4±6.3 HU vs. 56.1±6.8 HU, P=0.214; pancreas, 43.6±5.9 HU vs. 43.7±5.8 HU, P=0.785; spleen, 47.9±3.9 HU vs. 49.4±4.3 HU, P=0.128; kidney, 32.2±2.3 HU vs. 33.1±2.3 HU, P=0.367; abdominal aorta, 44.8±5.6 HU vs. 45.0±5.5 HU, P=0.499; psoas muscle, 50.7±4.1 HU vs. 50.3±4.5 HU, P=0.279). SNR on images of protocol 2 was higher than that of protocol 1(liver, 5.0±1.2 vs. 4.5±1.1, P<0.001; pancreas, 4.0±1.0 vs. 3.6±0.8, P<0.001; spleen, 4.7±1.0 vs. 4.1±0.9, P<0.001; kidney, 3.1±0.6 vs. 2.8±0.6, P<0.001; abdominal aorta, 4.1±1.0 vs. 3.8±1.0, P<0.001; psoas muscle, 4.5±1.1 vs. 4.3±1.2, P=0.012). The overall image noise of protocol 2 was lower than that of protocol1(9.8±3.1 HU vs. 11.1±3.0 HU, P<0.001). Image quality of protocol 2 was good but lower than that of protocol 1(4.1±0.7 vs. 4.6±0.5, P<0.001). Protocol 2 perceived 229 of 234 lesions(97.9%) that were detected in protocol 1 in the abdomen and pelvis. Radiation dose of protocol 2 was lower than that of protocol 1(4.4±0.4 m Sv vs. 7.3±2.4 m Sv, P<0.001) and the mean dose reduction was 41.4%. Conclusion The high-pitch DSCT with SAFIRE can shorten scan time and reduce radiation dose while preserving image quality in non-enhanced abdominal and pelvic scans.展开更多
Truncus arteriosus is an uncommon congenital cardiac abnormality which is characterized by a single arterial trunk origin from the heart that supplies both the systemic,pulmonary and coronary circulation.We present a ...Truncus arteriosus is an uncommon congenital cardiac abnormality which is characterized by a single arterial trunk origin from the heart that supplies both the systemic,pulmonary and coronary circulation.We present a preterm newborn female patient with type 2 truncusarteriosus,left superior vena cava and aberrant subclavian artery diagnosed with low dose dual-source cardiac computed tomography(CT).We discuss that low dose dual-source cardiac CT has more advantages than other imaging methods and it is an important modality for assessment of patients with conotruncal anomalies such as truncusarteriosus.展开更多
Background:Pulmonary atresia(PA)is a group of heterogeneous complex congenital heart disease.Only one study modality might not get a correct diagnosis.This study aims to investigate the diagnostic power of dualsource ...Background:Pulmonary atresia(PA)is a group of heterogeneous complex congenital heart disease.Only one study modality might not get a correct diagnosis.This study aims to investigate the diagnostic power of dualsource computed tomography(DSCT)for all intracardiac and extracardiac deformities in patients with PA compared with transthoracic echocardiography(TTE).Materials and Methods:This retrospective study enrolled 79 patients and divided them into three groups according to their main diagnosis.All associated malformations and clinical information,including treatments,were recorded and compared among the three groups.The diagnostic power of DSCT and TTE on all associated malformations were compared.The surgical index(McGoon ratio,pulmonary arterials index(PAI),and total neopulmonary arterial index)and radiation dose were calculated on the basis of DSCT.Results:Of the patients,32,30,and 17 were divided into the groups of PA with ventricular septal defect(VSD),PA with VSD and major aortopulmonary collateral arteries,and PA with other major malformations,respectively.Consequently,182,162,and 13 intracardiac,extracardiac,and other major malformations were diagnosed,respectively.Moreover,DSCT showed a better diagnostic performance in extracardiac deformities(154 vs.117,p<0.001),whereas TTE could diagnose intracardiac deformities better(159 vs.139,p=0.001).The McGoon ratio,PAI,and treatment methods were significantly different among the three groups(p=0.014,p=0.008,and p=0.018,respectively).Conclusion:More than one imaging modality should be used to make a correct diagnosis when clinically suspecting PA.DSCT is superior to TTE in diagnosing extracardiac deformities and could be used to roughly calculate surgical indices to optimize treatment strategy.展开更多
Objective To evaluate the image quality （IQ） and radiation dose of 128-slice dual-source computed tomography （DSCT） coronary angiography using prospectively electrocardiogram （ECG）-triggered sequen- tial scan mo...Objective To evaluate the image quality （IQ） and radiation dose of 128-slice dual-source computed tomography （DSCT） coronary angiography using prospectively electrocardiogram （ECG）-triggered sequen- tial scan mode compared with ECG-gated spiral scan mode in a population with atrial fibrillation. Methods Thirty-two patients with suspected coronary artery disease and permanent atrial fibrilla- tion referred for a second-generation 128-slice DSCT coronary angiography were included in the prospec- tive study. Of them, 17 patients （sequential group） were randomly selected to use a prospectively ECG.~triggered sequential scan, while the other 15 patients （spiral group） used a retrospectively ECG-gated spiral scan. The IQ was assessed by two readers independently, using a four-point grading scale from excel- lent （grade 1） to non-assessable （grade 4）, based on the American Heart Association 15-segment model. IQ of each segment and effective dose of each natient were comDared between the two groups. Results The mean heart rate （HR） of the sequential group was 96±27 beats per minute （bpm） with a variation range of 73±25 bpm, while the mean HR of the spiral group was 86±22 bpm with a variationrange of 65±24 bpm. Both of the mean FIR （t= 1.91, P=0.243） and HR variation range （t=0.950, P=0.350） had no significant difference between the two groups. In per-segment analysis, IQ of the sequential group vs. spiral group was rated as excellent （grade 1） in 190/244 （78%） vs. 177/217 （82%） by readerl and 197/245 （80%） vs. 174/214 （81%） by reader2, as non-assessable （grade 4） in 4/244 （2%） vs. 2/217 （1%） by readerl and 6/245 （2%） vs. 4/214 （2%） by reader2. Overall averaged IQ per-patient in the sequential and spiral group showed equally good （1.27＋0.19 vs. 1.25＋0.22, Z=-0.834, P=0.404）. The effective radiation dose of the sequential group reduced significantly compared with the spiral group （4.88±1.77 mSv vs. 10.20±3.64 mSv; t=-5.372, P=0.000）. Conclusion Compared with retrospectively ECG-gated spiral scan, prospectively ECG-triggered sequential DSCT coronary angiography provides similarly diagnostically valuable images in patients with atrial fibrillation and significantly reduces radiation dose.展开更多
Background:To evaluate the qualitative and quantitative differences between intracardiac and extracardiac vascular malformations in patients with a single atrium(SA),single ventricle(SV)and single atrium-single ventri...Background:To evaluate the qualitative and quantitative differences between intracardiac and extracardiac vascular malformations in patients with a single atrium(SA),single ventricle(SV)and single atrium-single ventricle(SA-SV)using dual-source CT(DSCT),and to compare the diagnostic performances of DSCT and transthoracic echocardiography(TTE).Methods:This retrospective study included 24 SA,75 SV and 24 SA-SV patients who underwent both DSCT and TTE before surgery.The diagnostic values of DSCT and TTE for intracardiac and extracardiac malformations were compared according to the surgical results.The diameters of the major artery and vein were measured and calculated based on DSCT and compared among the three groups.Results:The most common malformation was pulmonary artery disease in SA(50.0%)and SA-SV(45.8%)groups and patent ductus arteriosus(33.3%)in SV group.Although there was no statistical difference,arterial development was relatively poor in the SA group.All groups showed the trend of pulmonary artery stenosis(SA vs.SV vs.SA-SV:50.0%vs.30.7%vs.33.3%).There was a significant difference in mean pulmonary vein index among the groups(p=0.017).The diagnostic sensitivity of DSCT was superior to that of TTE for extracardiac malformations.Conclusions:The most common malformation in SA and SA-SV patients is pulmonary artery stenosis.SV patients are most likely to be complicated with patent ductus arteriosus.DSCT is more advantageous than TTE for diagnosing combined extracardiac malformations and can accurately measure the diameter of arteriovenous vessels.展开更多
Overt and harmful diabetes mellitus(DM)has detrimental effects on individuals and,by extension,the community.Among the microvascular DM complications is diabetic retinopathy(DR).DR may cause irreversible vision deteri...Overt and harmful diabetes mellitus(DM)has detrimental effects on individuals and,by extension,the community.Among the microvascular DM complications is diabetic retinopathy(DR).DR may cause irreversible vision deterioration in cases of poor blood glucose regulation.Changes in vascular permeability are key trigger points for diabetic macular edema(DME),a condition characterized by the accumulation of fluid in the macula.The development of vascular endothelial growth factor(VEGF)pathway inhibitors has provided a pathogenesis-based treatment approach for DME.Optical coherence tomography(OCT)provides highresolution imaging of the anatomy,including the aging of DME and its structural damage,in distinct morphologic subtypes of macular edema,thereby supporting the assessment of macular edema treatment.The availability of repeated OCT monitoring provides clinical reassurance through the treatment.OCT angiography(OCTA)provides retinal blood flow maps with high spatial resolution.The ability promotes an understanding of disease pathogenesis and facilitates the implementation of new therapeutic methods.This review compares the potential of OCT and OCTA in the diagnosis and treatment of DME,as well as their respective therapeutic applications.展开更多
Photoacoustic-computed tomography is a novel imaging technique that combines high absorption contrast and deep tissue penetration capability,enabling comprehensive three-dimensional imaging of biological targets.Howev...Photoacoustic-computed tomography is a novel imaging technique that combines high absorption contrast and deep tissue penetration capability,enabling comprehensive three-dimensional imaging of biological targets.However,the increasing demand for higher resolution and real-time imaging results in significant data volume,limiting data storage,transmission and processing efficiency of system.Therefore,there is an urgent need for an effective method to compress the raw data without compromising image quality.This paper presents a photoacoustic-computed tomography 3D data compression method and system based on Wavelet-Transformer.This method is based on the cooperative compression framework that integrates wavelet hard coding with deep learning-based soft decoding.It combines the multiscale analysis capability of wavelet transforms with the global feature modeling advantage of Transformers,achieving high-quality data compression and reconstruction.Experimental results using k-wave simulation suggest that the proposed compression system has advantages under extreme compression conditions,achieving a raw data compression ratio of up to 1:40.Furthermore,three-dimensional data compression experiment using in vivo mouse demonstrated that the maximum peak signal-to-noise ratio(PSNR)and structural similarity index(SSIM)values of reconstructed images reached 38.60 and 0.9583,effectively overcoming detail loss and artifacts introduced by raw data compression.All the results suggest that the proposed system can significantly reduce storage requirements and hardware cost,enhancing computational efficiency and image quality.These advantages support the development of photoacoustic-computed tomography toward higher efficiency,real-time performance and intelligent functionality.展开更多
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
Muon scattering tomography(MST) is a powerful noninvasive imaging technique with significant applications in nuclear material detection and security screening.Traditional MST usually relies on the point of closest app...Muon scattering tomography(MST) is a powerful noninvasive imaging technique with significant applications in nuclear material detection and security screening.Traditional MST usually relies on the point of closest approach(PoCA) algorithm to reconstruct images from muon scattering data;however,PoCA often suffers from suboptimal image clarity and resolution.To overcome these challenges,we propose a novel approach that leverages reinforcement learning(RL) to enhance MST reconstruction,termed the μRL-enhanced method.By framing the MST optimization task as an RL problem,we developed an intelligent agent capable of dynamically adjusting the key PoCA parameters.The agent is trained using a multi-objective reward function that guides the optimization toward higher-quality reconstructions.Our experimental results show that theμRL-enhanced method significantly outperforms the traditional PoCA baseline acros s multiple benchmark metrics.Specifically,the proposed approach on average attains a 307% improvement in the intersection over union(IoU),a 79% increase in the structural similarity index measure(SSIM),and a 8.4% enhancement in the peak signal-to-noise ratio(PSNR) across four experiments.Furthermore,when benchmarked against the maximum likelihood scattering and displacement(MLSD)algorithm,the μRL-enhanced method offers modest gains in PS NR and IoU,together with a one-third increase in SSIM.These improvements demonstrate the enhanced reconstruction accuracy and structural fidelity of the μRL-enhanced method,highlighting its potential to advance MST technologies and their applications.展开更多
The conventional optical coherence tomography angiography(OCTA)algorithm is implemented in the linear domain,which may lead to the neglect of weak blood flow information.Logarithmic transformation is widely used in si...The conventional optical coherence tomography angiography(OCTA)algorithm is implemented in the linear domain,which may lead to the neglect of weak blood flow information.Logarithmic transformation is widely used in signal analysis to improve the contrast of weak signals.However,decorrelation-based OCTA in the logarithmic domain is also sensitive to the signal-to-noise ratio(SNR)even in high SNR regions,introducing strong flow artifacts that severely reduce the blood vessel contrast.A metric—static-to-dynamic ratio(SDR)—was used to quantify weak flow signals,and a weak flow model among decorrelation,SDR,and SNR was established.Based on this model,we proposed a log-scale inverse SDR-based OCTA method(logiSDR-OCTA),which simultaneously and effectively reduces SNR-induced flow artifacts in static regions and prevents the attenuation of the flow signal in dynamic regions.The in vivo imaging experiments demonstrated that the contrast of the mouse brain logiSDR images was 2.43 times that of linear-scale decorrelation images and 2.71 times that of log-scale subtraction images;the contrast of the human retina logiSDR images was 4.91 times that of linear-scale decorrelation images and 3.56 times that of log-scale subtraction images.展开更多
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
Cement paste backfill(CPB)technology is a key method for mine waste treatment,and pipeline transport is critical for safe and efficient waste transfer.Variations in raw material properties can cause slurry segregation...Cement paste backfill(CPB)technology is a key method for mine waste treatment,and pipeline transport is critical for safe and efficient waste transfer.Variations in raw material properties can cause slurry segregation,increase pipeline wear and resistance,raise the risk of blockages or bursts,and disrupt operations.To study CPB slurry segregation during transport,CPB was prepared using cement as the cementitious material and unclassified tailings as inert materials.A small annular-tube device using an electrical resistance tomography system was developed to analyze its flow characteristics,and quantitative segregation assessment methods were developed.The results indicated that CPB conductivity increases with transport time but decreases with higher solid mass content,with the latter having a greater impact.At a low solid content,solid particles migrated toward the bottom of the pipe as the flow time increased,and the migratory behavior of the particles diminished as the solid content increased.At a flow rate of 1.25 m/s,the heterogeneity index for CPB with 58wt% solid content increased by 1.24 in 20 min,whereas that for CPB with 62wt% solid content increased by 2.17.Higher solid mass content amplifies the effect of conveying time on segregation,emphasizing the need to balance these factors for minimizing segregation.These insights can guide the optimization of mine pipeline transport systems.展开更多
Intense light diffusion and attenuation through turbid biological tissues compromise the achievable depth,resolution,and contrast in optoacoustic tomography(OAT).We propose to mitigate this limitation by exploiting ul...Intense light diffusion and attenuation through turbid biological tissues compromise the achievable depth,resolution,and contrast in optoacoustic tomography(OAT).We propose to mitigate this limitation by exploiting ultrasound waves to locally modulate the refractive index of scattering samples,effectively generating embedded light waveguides.Here,the ultrasound-induced waveguides enhanced light delivery into deep targets,achieving up to 110%improvement in contrast-to-noise ratio of OAT images at a depth of eight mean free scattering paths.Furthermore,ultrasound-mediated light focusing enables breaking through the acoustic diffraction limit by attaining 25μm spatial resolution via localization OAT without the need for external circulating contrast agents.These findings demonstrate the potential of ultrasoundinduced light guiding for enabling label-free super-resolution OAT with enhanced contrast and depth.展开更多
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
Female reproductive tract lesions are diverse,ranging from benign inflammation to malignant tumors,all of which seriously threaten women’s health.Early accurate diagnosis is crucial for improving prognosis.As the“go...Female reproductive tract lesions are diverse,ranging from benign inflammation to malignant tumors,all of which seriously threaten women’s health.Early accurate diagnosis is crucial for improving prognosis.As the“gold standard”for diagnosis,histopathological examination is difficult to meet the needs of clinical screening and dynamic monitoring due to limitations such as invasiveness and sampling restrictions.Optical Coherence Tomography(OCT),as a non-invasive,real-time,and high-resolution imaging technology,can clearly display the microstructure of biological tissues,known as“optical biopsy”,and shows promising application prospects in the diagnosis of female reproductive tract lesions.This article systematically reviews the basic principles of OCT technology,the research progress on the correlation between OCT image features and histological features in lesions of different parts of the female reproductive tract such as the cervix and endometrium,analyzes the diagnostic efficacy,advantages and limitations of OCT technology,and prospects its future development direction,aiming to provide a reference for the clinical application of OCT technology in the diagnosis of female reproductive tract diseases.展开更多
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
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
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
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
Objective:The current pathological diagnosis of lymph node metastasis is time-consuming,labor-intensive,and dependent on sectioning of paraffin blocks.Herein,in a prospective cohort of patients with breast cancer,we v...Objective:The current pathological diagnosis of lymph node metastasis is time-consuming,labor-intensive,and dependent on sectioning of paraffin blocks.Herein,in a prospective cohort of patients with breast cancer,we validated dynamic full-field optical coherence tomography(D-FFOCT),a virtual pathology tool integrating deep learning for nodal metastasis detection,and offering rapid and label-free histologic approximations of fresh tissues.Methods:In a prospective dual-center cohort of 155 patients with breast cancer,747 freshly bisected lymph node slides were obtained via D-FFOCT.Surgeons interpreted each slide with histopathology as the gold standard.A deep learning model was trained on 28,911 patches(corresponding to 590 slides)and tested on 7,736 patches(corresponding to 157 slides).The results were mapped to the slide level for potential intraoperative evaluation.Results:D-FFOCT strongly correlated with hematoxylin and eosin(H&E)-stained histological images.Surgeons achieved 97.10%specificity in nodal diagnosis with D-FFOCT.The performance of the artificial intelligence(AI)model was not inferior to that of human experts and had a sensitivity/specificity of 87.88%/91.94%and an area under the receiver operating characteristic curve of 0.899 at the slide level.The human–AI collaborative system reduced labor requirements by 75%and increased the specificity by 6.5%,to 98.39%.Conclusions:D-FFOCT has excellent potential as a tool for assessing lymph node metastatic status without tissue preparation or consumption.The integration of D-FFOCT with deep learning decreases labor demands and maintains high accuracy,thereby enabling streamlined nodal prediction independent of routine pathology procedures.展开更多
文摘Objective To investigate the image quality, radiation dose and diagnostic value of the low-tube-voltage high-pitch dual-source computed tomography(DSCT) with sinogram affirmed iterative reconstruction(SAFIRE) for non-enhanced abdominal and pelvic scans. Methods This institutional review board-approved prospective study included 64 patients who gave written informed consent for additional abdominal and pelvic scan with DSCT in the period from November to December 2012. The patients underwent standard non-enhanced CT scans(protocol 1) [tube voltage of 120 k Vp/pitch of 0.9/filtered back-projection(FBP) reconstruction] followed by high-pitch non-enhanced CT scans(protocol 2)(100 k Vp/3.0/SAFIRE). The total scan time, mean CT number, signal-to-noise ratio(SNR), image quality, lesion detectability and radiation dose were compared between the two protocols. Results The total scan time of protocol 2 was significantly shorter than that of protocol 1(1.4±0.1 seconds vs. 7.6±0.6 seconds, P<0.001). There was no significant difference between protocol 1 and protocol 2 in mean CT number of all organs(liver, 55.4±6.3 HU vs. 56.1±6.8 HU, P=0.214; pancreas, 43.6±5.9 HU vs. 43.7±5.8 HU, P=0.785; spleen, 47.9±3.9 HU vs. 49.4±4.3 HU, P=0.128; kidney, 32.2±2.3 HU vs. 33.1±2.3 HU, P=0.367; abdominal aorta, 44.8±5.6 HU vs. 45.0±5.5 HU, P=0.499; psoas muscle, 50.7±4.1 HU vs. 50.3±4.5 HU, P=0.279). SNR on images of protocol 2 was higher than that of protocol 1(liver, 5.0±1.2 vs. 4.5±1.1, P<0.001; pancreas, 4.0±1.0 vs. 3.6±0.8, P<0.001; spleen, 4.7±1.0 vs. 4.1±0.9, P<0.001; kidney, 3.1±0.6 vs. 2.8±0.6, P<0.001; abdominal aorta, 4.1±1.0 vs. 3.8±1.0, P<0.001; psoas muscle, 4.5±1.1 vs. 4.3±1.2, P=0.012). The overall image noise of protocol 2 was lower than that of protocol1(9.8±3.1 HU vs. 11.1±3.0 HU, P<0.001). Image quality of protocol 2 was good but lower than that of protocol 1(4.1±0.7 vs. 4.6±0.5, P<0.001). Protocol 2 perceived 229 of 234 lesions(97.9%) that were detected in protocol 1 in the abdomen and pelvis. Radiation dose of protocol 2 was lower than that of protocol 1(4.4±0.4 m Sv vs. 7.3±2.4 m Sv, P<0.001) and the mean dose reduction was 41.4%. Conclusion The high-pitch DSCT with SAFIRE can shorten scan time and reduce radiation dose while preserving image quality in non-enhanced abdominal and pelvic scans.
文摘Truncus arteriosus is an uncommon congenital cardiac abnormality which is characterized by a single arterial trunk origin from the heart that supplies both the systemic,pulmonary and coronary circulation.We present a preterm newborn female patient with type 2 truncusarteriosus,left superior vena cava and aberrant subclavian artery diagnosed with low dose dual-source cardiac computed tomography(CT).We discuss that low dose dual-source cardiac CT has more advantages than other imaging methods and it is an important modality for assessment of patients with conotruncal anomalies such as truncusarteriosus.
基金This study was approved by the Institutional Ethics Committee of West China Hospital,Sichuan University (Chengdu, Sichuan, ChinaNo. 14-163)+1 种基金This study has received funding by Sichuan Science and Technology Program(2020YJ0229)1⋅3⋅5 Project for Disciplines of Excellence,West China Hospital,Sichuan University(ZYGD18013)。
文摘Background:Pulmonary atresia(PA)is a group of heterogeneous complex congenital heart disease.Only one study modality might not get a correct diagnosis.This study aims to investigate the diagnostic power of dualsource computed tomography(DSCT)for all intracardiac and extracardiac deformities in patients with PA compared with transthoracic echocardiography(TTE).Materials and Methods:This retrospective study enrolled 79 patients and divided them into three groups according to their main diagnosis.All associated malformations and clinical information,including treatments,were recorded and compared among the three groups.The diagnostic power of DSCT and TTE on all associated malformations were compared.The surgical index(McGoon ratio,pulmonary arterials index(PAI),and total neopulmonary arterial index)and radiation dose were calculated on the basis of DSCT.Results:Of the patients,32,30,and 17 were divided into the groups of PA with ventricular septal defect(VSD),PA with VSD and major aortopulmonary collateral arteries,and PA with other major malformations,respectively.Consequently,182,162,and 13 intracardiac,extracardiac,and other major malformations were diagnosed,respectively.Moreover,DSCT showed a better diagnostic performance in extracardiac deformities(154 vs.117,p<0.001),whereas TTE could diagnose intracardiac deformities better(159 vs.139,p=0.001).The McGoon ratio,PAI,and treatment methods were significantly different among the three groups(p=0.014,p=0.008,and p=0.018,respectively).Conclusion:More than one imaging modality should be used to make a correct diagnosis when clinically suspecting PA.DSCT is superior to TTE in diagnosing extracardiac deformities and could be used to roughly calculate surgical indices to optimize treatment strategy.
文摘Objective To evaluate the image quality （IQ） and radiation dose of 128-slice dual-source computed tomography （DSCT） coronary angiography using prospectively electrocardiogram （ECG）-triggered sequen- tial scan mode compared with ECG-gated spiral scan mode in a population with atrial fibrillation. Methods Thirty-two patients with suspected coronary artery disease and permanent atrial fibrilla- tion referred for a second-generation 128-slice DSCT coronary angiography were included in the prospec- tive study. Of them, 17 patients （sequential group） were randomly selected to use a prospectively ECG.~triggered sequential scan, while the other 15 patients （spiral group） used a retrospectively ECG-gated spiral scan. The IQ was assessed by two readers independently, using a four-point grading scale from excel- lent （grade 1） to non-assessable （grade 4）, based on the American Heart Association 15-segment model. IQ of each segment and effective dose of each natient were comDared between the two groups. Results The mean heart rate （HR） of the sequential group was 96±27 beats per minute （bpm） with a variation range of 73±25 bpm, while the mean HR of the spiral group was 86±22 bpm with a variationrange of 65±24 bpm. Both of the mean FIR （t= 1.91, P=0.243） and HR variation range （t=0.950, P=0.350） had no significant difference between the two groups. In per-segment analysis, IQ of the sequential group vs. spiral group was rated as excellent （grade 1） in 190/244 （78%） vs. 177/217 （82%） by readerl and 197/245 （80%） vs. 174/214 （81%） by reader2, as non-assessable （grade 4） in 4/244 （2%） vs. 2/217 （1%） by readerl and 6/245 （2%） vs. 4/214 （2%） by reader2. Overall averaged IQ per-patient in the sequential and spiral group showed equally good （1.27＋0.19 vs. 1.25＋0.22, Z=-0.834, P=0.404）. The effective radiation dose of the sequential group reduced significantly compared with the spiral group （4.88±1.77 mSv vs. 10.20±3.64 mSv; t=-5.372, P=0.000）. Conclusion Compared with retrospectively ECG-gated spiral scan, prospectively ECG-triggered sequential DSCT coronary angiography provides similarly diagnostically valuable images in patients with atrial fibrillation and significantly reduces radiation dose.
基金This work was supported by Sichuan Science and Technology Program[2020YJ0229]1·3·5 Project for Disciplines of Excellence,West China Hospital,Sichuan University[ZYGD18013].
文摘Background:To evaluate the qualitative and quantitative differences between intracardiac and extracardiac vascular malformations in patients with a single atrium(SA),single ventricle(SV)and single atrium-single ventricle(SA-SV)using dual-source CT(DSCT),and to compare the diagnostic performances of DSCT and transthoracic echocardiography(TTE).Methods:This retrospective study included 24 SA,75 SV and 24 SA-SV patients who underwent both DSCT and TTE before surgery.The diagnostic values of DSCT and TTE for intracardiac and extracardiac malformations were compared according to the surgical results.The diameters of the major artery and vein were measured and calculated based on DSCT and compared among the three groups.Results:The most common malformation was pulmonary artery disease in SA(50.0%)and SA-SV(45.8%)groups and patent ductus arteriosus(33.3%)in SV group.Although there was no statistical difference,arterial development was relatively poor in the SA group.All groups showed the trend of pulmonary artery stenosis(SA vs.SV vs.SA-SV:50.0%vs.30.7%vs.33.3%).There was a significant difference in mean pulmonary vein index among the groups(p=0.017).The diagnostic sensitivity of DSCT was superior to that of TTE for extracardiac malformations.Conclusions:The most common malformation in SA and SA-SV patients is pulmonary artery stenosis.SV patients are most likely to be complicated with patent ductus arteriosus.DSCT is more advantageous than TTE for diagnosing combined extracardiac malformations and can accurately measure the diameter of arteriovenous vessels.
文摘Overt and harmful diabetes mellitus(DM)has detrimental effects on individuals and,by extension,the community.Among the microvascular DM complications is diabetic retinopathy(DR).DR may cause irreversible vision deterioration in cases of poor blood glucose regulation.Changes in vascular permeability are key trigger points for diabetic macular edema(DME),a condition characterized by the accumulation of fluid in the macula.The development of vascular endothelial growth factor(VEGF)pathway inhibitors has provided a pathogenesis-based treatment approach for DME.Optical coherence tomography(OCT)provides highresolution imaging of the anatomy,including the aging of DME and its structural damage,in distinct morphologic subtypes of macular edema,thereby supporting the assessment of macular edema treatment.The availability of repeated OCT monitoring provides clinical reassurance through the treatment.OCT angiography(OCTA)provides retinal blood flow maps with high spatial resolution.The ability promotes an understanding of disease pathogenesis and facilitates the implementation of new therapeutic methods.This review compares the potential of OCT and OCTA in the diagnosis and treatment of DME,as well as their respective therapeutic applications.
基金supported by the National Key R&D Program of China[Grant No.2023YFF0713600]the National Natural Science Foundation of China[Grant No.62275062]+3 种基金Project of Shandong Innovation and Startup Community of High-end Medical Apparatus and Instruments[Grant No.2023-SGTTXM-002 and 2024-SGTTXM-005]the Shandong Province Technology Innovation Guidance Plan(Central Leading Local Science and Technology Development Fund)[Grant No.YDZX2023115]the Taishan Scholar Special Funding Project of Shandong Provincethe Shandong Laboratory of Advanced Biomaterials and Medical Devices in Weihai[Grant No.ZL202402].
文摘Photoacoustic-computed tomography is a novel imaging technique that combines high absorption contrast and deep tissue penetration capability,enabling comprehensive three-dimensional imaging of biological targets.However,the increasing demand for higher resolution and real-time imaging results in significant data volume,limiting data storage,transmission and processing efficiency of system.Therefore,there is an urgent need for an effective method to compress the raw data without compromising image quality.This paper presents a photoacoustic-computed tomography 3D data compression method and system based on Wavelet-Transformer.This method is based on the cooperative compression framework that integrates wavelet hard coding with deep learning-based soft decoding.It combines the multiscale analysis capability of wavelet transforms with the global feature modeling advantage of Transformers,achieving high-quality data compression and reconstruction.Experimental results using k-wave simulation suggest that the proposed compression system has advantages under extreme compression conditions,achieving a raw data compression ratio of up to 1:40.Furthermore,three-dimensional data compression experiment using in vivo mouse demonstrated that the maximum peak signal-to-noise ratio(PSNR)and structural similarity index(SSIM)values of reconstructed images reached 38.60 and 0.9583,effectively overcoming detail loss and artifacts introduced by raw data compression.All the results suggest that the proposed system can significantly reduce storage requirements and hardware cost,enhancing computational efficiency and image quality.These advantages support the development of photoacoustic-computed tomography toward higher efficiency,real-time performance and intelligent functionality.
基金Project(2023YFB4606200)supported by the National Key Research and Development Program of ChinaProject(2023-SSRF-HZ-503114-2)supported by Shanghai Synchrotron Radiation Facility,Instrument BL16U2,China。
文摘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.
基金supported by the National Natural Science Foundation of China (No.12222502)。
文摘Muon scattering tomography(MST) is a powerful noninvasive imaging technique with significant applications in nuclear material detection and security screening.Traditional MST usually relies on the point of closest approach(PoCA) algorithm to reconstruct images from muon scattering data;however,PoCA often suffers from suboptimal image clarity and resolution.To overcome these challenges,we propose a novel approach that leverages reinforcement learning(RL) to enhance MST reconstruction,termed the μRL-enhanced method.By framing the MST optimization task as an RL problem,we developed an intelligent agent capable of dynamically adjusting the key PoCA parameters.The agent is trained using a multi-objective reward function that guides the optimization toward higher-quality reconstructions.Our experimental results show that theμRL-enhanced method significantly outperforms the traditional PoCA baseline acros s multiple benchmark metrics.Specifically,the proposed approach on average attains a 307% improvement in the intersection over union(IoU),a 79% increase in the structural similarity index measure(SSIM),and a 8.4% enhancement in the peak signal-to-noise ratio(PSNR) across four experiments.Furthermore,when benchmarked against the maximum likelihood scattering and displacement(MLSD)algorithm,the μRL-enhanced method offers modest gains in PS NR and IoU,together with a one-third increase in SSIM.These improvements demonstrate the enhanced reconstruction accuracy and structural fidelity of the μRL-enhanced method,highlighting its potential to advance MST technologies and their applications.
基金supported by the National Key R&D Program of China(Grant Nos.2021YFF0700503,2022YFC2404201,and 2021YFF0700700)the Natural Science Foundation of Jiangsu Province(Grant Nos.BK20240024 and BK20220263)+3 种基金the Strategic Priority Research Program of the Chinese Academy(Grant No.XDB1020000)the Suzhou Pilot Program for Basic Research(Grant No.SSD2023018)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.Y2023087)the National Natural Science Foundation of China(Grant No.62075235)。
文摘The conventional optical coherence tomography angiography(OCTA)algorithm is implemented in the linear domain,which may lead to the neglect of weak blood flow information.Logarithmic transformation is widely used in signal analysis to improve the contrast of weak signals.However,decorrelation-based OCTA in the logarithmic domain is also sensitive to the signal-to-noise ratio(SNR)even in high SNR regions,introducing strong flow artifacts that severely reduce the blood vessel contrast.A metric—static-to-dynamic ratio(SDR)—was used to quantify weak flow signals,and a weak flow model among decorrelation,SDR,and SNR was established.Based on this model,we proposed a log-scale inverse SDR-based OCTA method(logiSDR-OCTA),which simultaneously and effectively reduces SNR-induced flow artifacts in static regions and prevents the attenuation of the flow signal in dynamic regions.The in vivo imaging experiments demonstrated that the contrast of the mouse brain logiSDR images was 2.43 times that of linear-scale decorrelation images and 2.71 times that of log-scale subtraction images;the contrast of the human retina logiSDR images was 4.91 times that of linear-scale decorrelation images and 3.56 times that of log-scale subtraction images.
基金supported by the financial support received from the Indian Council of Medical Research-Department of Health Research(ICMRDHR-CoE-5/3/8/5/2019/I-MDMS)Medical Device and Diagnostics Mission Secretariat(MDMS)and Foundation for Centre for Healthcare Entrepreneurship(CfHE).
文摘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.
基金supported by the National Natural ScienceFoundation of China(Nos.52427804 and 52574136).
文摘Cement paste backfill(CPB)technology is a key method for mine waste treatment,and pipeline transport is critical for safe and efficient waste transfer.Variations in raw material properties can cause slurry segregation,increase pipeline wear and resistance,raise the risk of blockages or bursts,and disrupt operations.To study CPB slurry segregation during transport,CPB was prepared using cement as the cementitious material and unclassified tailings as inert materials.A small annular-tube device using an electrical resistance tomography system was developed to analyze its flow characteristics,and quantitative segregation assessment methods were developed.The results indicated that CPB conductivity increases with transport time but decreases with higher solid mass content,with the latter having a greater impact.At a low solid content,solid particles migrated toward the bottom of the pipe as the flow time increased,and the migratory behavior of the particles diminished as the solid content increased.At a flow rate of 1.25 m/s,the heterogeneity index for CPB with 58wt% solid content increased by 1.24 in 20 min,whereas that for CPB with 62wt% solid content increased by 2.17.Higher solid mass content amplifies the effect of conveying time on segregation,emphasizing the need to balance these factors for minimizing segregation.These insights can guide the optimization of mine pipeline transport systems.
基金supported by the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation program(Grant No.101002460)。
文摘Intense light diffusion and attenuation through turbid biological tissues compromise the achievable depth,resolution,and contrast in optoacoustic tomography(OAT).We propose to mitigate this limitation by exploiting ultrasound waves to locally modulate the refractive index of scattering samples,effectively generating embedded light waveguides.Here,the ultrasound-induced waveguides enhanced light delivery into deep targets,achieving up to 110%improvement in contrast-to-noise ratio of OAT images at a depth of eight mean free scattering paths.Furthermore,ultrasound-mediated light focusing enables breaking through the acoustic diffraction limit by attaining 25μm spatial resolution via localization OAT without the need for external circulating contrast agents.These findings demonstrate the potential of ultrasoundinduced light guiding for enabling label-free super-resolution OAT with enhanced contrast and depth.
基金supported by the Guangdong Pharmaceutical University 2024 Higher Education Research Projects(GKP202403,GMP202402)the Guangdong Pharmaceutical University College Students’Innovation and Entrepreneurship Training Programs(Grant No.202504302033,202504302034,202504302036,and 202504302244).
文摘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.
基金2022 University-Level Scientific Research Project(Project No.:KJ2022-19)Innovation Project for Undergraduate Students in 2025(Project No.:bkcx2025035)。
文摘Female reproductive tract lesions are diverse,ranging from benign inflammation to malignant tumors,all of which seriously threaten women’s health.Early accurate diagnosis is crucial for improving prognosis.As the“gold standard”for diagnosis,histopathological examination is difficult to meet the needs of clinical screening and dynamic monitoring due to limitations such as invasiveness and sampling restrictions.Optical Coherence Tomography(OCT),as a non-invasive,real-time,and high-resolution imaging technology,can clearly display the microstructure of biological tissues,known as“optical biopsy”,and shows promising application prospects in the diagnosis of female reproductive tract lesions.This article systematically reviews the basic principles of OCT technology,the research progress on the correlation between OCT image features and histological features in lesions of different parts of the female reproductive tract such as the cervix and endometrium,analyzes the diagnostic efficacy,advantages and limitations of OCT technology,and prospects its future development direction,aiming to provide a reference for the clinical application of OCT technology in the diagnosis of female reproductive tract diseases.
基金supported by the Key Research and Development Program of the Xinjiang Uygur Autonomous Region(No.2020B03006-1)the National Natural Science Foundation of China(Nos.42304069,and 42102275).
文摘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.
文摘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.
文摘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.
基金PEEP titration in ARDS patients using EIT combined with lung ultrasound,Key Laboratory of Emergency Trauma Research,Ministry of Education (KLET-202201)airway clearance protocol in ICU mechanically ventilated patients based on electrical impedance imaging technology,Natural Science Foundation of Hunan Province (2024JJ9148)effects of end expiratory positive pressure on lung re-expansion in patients with ARDS and intra-abdominal hypertension monitored using lung ultrasound,Natural Science Foundation of Hunan Province (2023JJ60308)
文摘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.
基金supported by grants from the National Key Research and Development Program of China(Grant No.2024YFC3405303)Beijing Natural Science Foundation(Grant No.7242281 and 7244427)Research and Development Fund of Peking University People’s Hospital(Grant No.RDZH2024-03 and RDEB2025-25).
文摘Objective:The current pathological diagnosis of lymph node metastasis is time-consuming,labor-intensive,and dependent on sectioning of paraffin blocks.Herein,in a prospective cohort of patients with breast cancer,we validated dynamic full-field optical coherence tomography(D-FFOCT),a virtual pathology tool integrating deep learning for nodal metastasis detection,and offering rapid and label-free histologic approximations of fresh tissues.Methods:In a prospective dual-center cohort of 155 patients with breast cancer,747 freshly bisected lymph node slides were obtained via D-FFOCT.Surgeons interpreted each slide with histopathology as the gold standard.A deep learning model was trained on 28,911 patches(corresponding to 590 slides)and tested on 7,736 patches(corresponding to 157 slides).The results were mapped to the slide level for potential intraoperative evaluation.Results:D-FFOCT strongly correlated with hematoxylin and eosin(H&E)-stained histological images.Surgeons achieved 97.10%specificity in nodal diagnosis with D-FFOCT.The performance of the artificial intelligence(AI)model was not inferior to that of human experts and had a sensitivity/specificity of 87.88%/91.94%and an area under the receiver operating characteristic curve of 0.899 at the slide level.The human–AI collaborative system reduced labor requirements by 75%and increased the specificity by 6.5%,to 98.39%.Conclusions:D-FFOCT has excellent potential as a tool for assessing lymph node metastatic status without tissue preparation or consumption.The integration of D-FFOCT with deep learning decreases labor demands and maintains high accuracy,thereby enabling streamlined nodal prediction independent of routine pathology procedures.
