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
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
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
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
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
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
Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance to...Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance tomography enables real-time monitoring of changes in cerebral blood perfusion within the ischemic brain,but investigating the feasibility of using this method to assess post-stroke rehabilitation in vivo remains critical.In this study,ischemic stroke was induced in rats through middle cerebral artery occlusion surgery.Transcranial focused ultrasound stimulation was used to treat the rat model of ischemia,and electrical impedance tomography was used to measure impedance during both the acute stage of ischemia and the rehabilitation stage following the stimulation.Electrical impedance tomography results indicated that cerebral impedance increased after the onset of ischemia and decreased following transcranial focused ultrasound stimulation.Furthermore,the stimulation promoted motor function recovery,reduced cerebral infarction volume in the rat model of ischemic stroke,and induced the expression of brain-derived neurotrophic factor in the ischemic brain.Our results also revealed a significant correlation between the impedance of the ischemic brain post-intervention and improvements in behavioral scores and infarct volume.This study shows that daily administration of transcranial focused ultrasound stimulation for 20 minutes to the ischemic hemisphere 24 hours after cerebral ischemia enhanced motor recovery in a rat model of ischemia.Additionally,our findings indicate that electrical impedance tomography can serve as a valuable tool for quantitatively evaluating rehabilitation after ischemic stroke in vivo.These findings suggest the feasibility of using impedance data collected via electrical impedance tomography to clinically assess the effects of rehabilitatory interventions for patients with ischemic stroke.展开更多
Objective To prospectively investigate the diagnostic accuracy for coronary artery stenosis of prospectively electrocardiogram-triggered spiral acquisition mode (high pitch mode) dual-source computed tomography corona...Objective To prospectively investigate the diagnostic accuracy for coronary artery stenosis of prospectively electrocardiogram-triggered spiral acquisition mode (high pitch mode) dual-source computed tomography coronary angiography (CTCA) in patients with relatively higher heart rates (HR) compared with catheter coronary angiography (CCA). Methods Forty-seven consecutive patients with relatively higher HR (>65 and <100 bpm) (20 male, 27 female; age 55±10 years) who both underwent dual-source CTCA and CCA were prospectively included in this study. All patients were performed CTCA using high pitch mode setting at 20%-30% of the R-R interval for the image acquisition. All coronary segments were evaluated by two blinded and independent observers with regard to image quality on a three-point scale (1: excellent to 3: non-diagnostic) and for the presence of significant coronary stenoses (defined as diameter narrowing exceeding 50%). Considered CCA as the standard of reference, the sensitivity, specificity, positive predictive value and negative predictive value were calculated. Radiation dose values were calculated using the dose-length product. Results Image quality was rated as being score 1 in 92.4% of segments, score 2 in 6.1% of segmentsand score 3 in 1.5% of segments. The average image quality score per segment was 1.064±0.306. The HR variability of patients with image score 1, 2 and 3 were 2.29±1.06 bpm, 5.17±1.37 bpm, 8.88±1.53 bpm, respectively. The average HR variability of patients with different image scores were significantly different (F=170.402, P=0.001). The sensitivity, specificity, positive and negative predictive values were 92.6%, 97.0%, 87.6%, 98.3%, respectively, per segment and 90.0%, 95.2%, 85.3%, 96.9%, respectively, per vessel and 100%, 63.6%, 90.0%, 100%, respectively, per patient. The effective radiation dose was on average 0.86±0.16 mSv. Conclusion In patients with HR more than 65 bpm and below 100 bpm without cardiac arrhythmia, the prospectively electrocardiogram-gated high-pitch spiral acquisition mode with image acquired timing set at 20%-30% of the R-R interval provides a high diagnostic accuracy for the assessment of coronary stenoses combined with a 1.5% of non-diagnostic coronary segments and a radiation dose below 1 mSv.展开更多
Objective To investigate the feasibility of acquiring the similar homogeneous enhancement using bolus-tracking techniques with shortened respiratory time in prospectively electrocardiogram-gated high-pitch spiral acqu...Objective To investigate the feasibility of acquiring the similar homogeneous enhancement using bolus-tracking techniques with shortened respiratory time in prospectively electrocardiogram-gated high-pitch spiral acquisition mode (Flash mode) coronary computed tomography angiography (CCTA) compared with test bolus technique. Methods One hundred and eighty-four consecutive patients with mean heart rate ≤65 beats per minute undergoing CCTA were prospectively included in this study. The patients were randomly divided into two groups. Patients in the group A (n=92) instructed to shorten respiratory time received CCTA using bolus-tracking technique with high-pitch spiral acquisition mode (Flash mode), while those in the group B (n=92) underwent CCTA with test bolus technique. The attenuation in the ascending aorta, image noise, contrast-to-noise ratio and radiation doses of the two groups were assessed. Results There were no significant differences in the mean attenuation values in the ascending aorta (483.18±59.07 HU vs. 498.7±83.51 HU, P=0.183), image noise (21.4±4.5 HU vs. 20.9±4.3 HU, P=0.414), contrast-to-noise ratio (12.1±4.2 vs. 13.8±5.1, P=0.31) between the groups A and B. There were no significant differences in the radiation dose of dynamic monitoring scans (0.056±0.026 mSv vs. 0.062±0.018 mSv, P=0.068) and radiation dose of angiography (0.94±0.07 mSv vs. 0.96±0.15 mSv,P=0.926) between the two groups, while 15 mL less contrast material volume was administered in the group A than the group B. Conclusion Bolus-tracking technique with shortened time of respiratory in Flash mode of dual-source CT yields the similar homogeneous enhancement with less contrast material in comparison to the test bolus technique.展开更多
We report on tests of combined positron emission tomography(PET)andfluorescence molecular tomography(FMT)imaging system for in vivo investigation on small animals.A nude mouse was inoculated with MD-MB-231 breast canc...We report on tests of combined positron emission tomography(PET)andfluorescence molecular tomography(FMT)imaging system for in vivo investigation on small animals.A nude mouse was inoculated with MD-MB-231 breast cancer cells which expressed redfluorescent protein(RFP).For FMT system,reflective illumination mode was adopted with full-angle data acquisition.[18F]-Fluorodeoxyglucose([18F]-FDG)was used as radioactive tracer for PET.Both data were acquired simultaneously and then reconstructed separately before fusion.Fluorescent tomography results showed exactly where the tumor was located while PET results offered more metabolic information.Results confirmed feasibility for tumor detection and showed superiority to single modality imaging.展开更多
Objective: On the premise that the image quality meets the requirements of clinical diagnosis, we explored the methods to reduce the radiation dose of coronary artery imaging with Dual-Source CT (DSCT). Methods: We ra...Objective: On the premise that the image quality meets the requirements of clinical diagnosis, we explored the methods to reduce the radiation dose of coronary artery imaging with Dual-Source CT (DSCT). Methods: We randomly selected 200 patients with coronary heat disease (BIM 0.05). The average image noise in group A is (41.76 ± 7.98) HU, in group B the average image noise is (43.97 ± 3.88) HU, the dif- ference between the two groups was not statistically significant (P>0.05). The average CTDIvol of group A and B were (20.63 ± 2.24) mGy, (38.11 ± 10.69) mGy, respectively, then P <0.01. The average DLP of group A and B are (235.75 ± 28.64) mGycm and (492.59 ± 125.49) mGycm respectively, then P <0.01, the dif- ference of radiation dose had statistical significance (P<0.05). Conclusions: For coronary artery imaging with DSCT the heart electric pulse (AUTO) regulation technology can meet the diagnostic requirements and effectively reduce the radiation dose.展开更多
Photon-counting computed tomography(PCCT)represents a significant advancement in pediatric cardiovascular imaging.Traditional CT systems employ energy-integrating detectors that convert X-ray photons into visible ligh...Photon-counting computed tomography(PCCT)represents a significant advancement in pediatric cardiovascular imaging.Traditional CT systems employ energy-integrating detectors that convert X-ray photons into visible light,whereas PCCT utilizes photon-counting detectors that directly transform X-ray photons into electric signals.This direct conversion allows photon-counting detectors to sort photons into discrete energy levels,thereby enhancing image quality through superior noise reduction,improved spatial and contrast resolution,and reduced artifacts.In pediatric applications,PCCT offers substantial benefits,including lower radiation doses,which may help reduce the risk of malignancy in pediatric patients,with perhaps greater potential to benefit those with repeated exposure from a young age.Enhanced spatial resolution facilitates better visualization of small structures,vital for diagnosing congenital heart defects.Additionally,PCCT’s spectral capabilities improve tissue characterization and enable the creation of virtual monoenergetic images,which enhance soft-tissue contrast and potentially reduce contrast media doses.Initial clinical results indicate that PCCT provides superior image quality and diagnostic accuracy compared to conven-tional CT,particularly in challenging pediatric cardiovascular cases.As PCCT technology matures,further research and standardized protocols will be essential to fully integrate it into pediatric imaging practices,ensuring optimized diagnostic outcomes and patient safety.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 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 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.
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.
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supported by the Fundamental Research Funds for the Central Universities,Nos.G2021KY05107,G2021KY05101the National Natural Science Foundation of China,Nos.32071316,32211530049+1 种基金the Natural Science Foundation of Shaanxi Province,No.2022-JM482the Education and Teaching Reform Funds for the Central Universities,No.23GZ230102(all to LL and HH).
文摘Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance tomography enables real-time monitoring of changes in cerebral blood perfusion within the ischemic brain,but investigating the feasibility of using this method to assess post-stroke rehabilitation in vivo remains critical.In this study,ischemic stroke was induced in rats through middle cerebral artery occlusion surgery.Transcranial focused ultrasound stimulation was used to treat the rat model of ischemia,and electrical impedance tomography was used to measure impedance during both the acute stage of ischemia and the rehabilitation stage following the stimulation.Electrical impedance tomography results indicated that cerebral impedance increased after the onset of ischemia and decreased following transcranial focused ultrasound stimulation.Furthermore,the stimulation promoted motor function recovery,reduced cerebral infarction volume in the rat model of ischemic stroke,and induced the expression of brain-derived neurotrophic factor in the ischemic brain.Our results also revealed a significant correlation between the impedance of the ischemic brain post-intervention and improvements in behavioral scores and infarct volume.This study shows that daily administration of transcranial focused ultrasound stimulation for 20 minutes to the ischemic hemisphere 24 hours after cerebral ischemia enhanced motor recovery in a rat model of ischemia.Additionally,our findings indicate that electrical impedance tomography can serve as a valuable tool for quantitatively evaluating rehabilitation after ischemic stroke in vivo.These findings suggest the feasibility of using impedance data collected via electrical impedance tomography to clinically assess the effects of rehabilitatory interventions for patients with ischemic stroke.
基金Supported by the Ministry of Science and Technology of Inner Mongolia, China (20110504)
文摘Objective To prospectively investigate the diagnostic accuracy for coronary artery stenosis of prospectively electrocardiogram-triggered spiral acquisition mode (high pitch mode) dual-source computed tomography coronary angiography (CTCA) in patients with relatively higher heart rates (HR) compared with catheter coronary angiography (CCA). Methods Forty-seven consecutive patients with relatively higher HR (>65 and <100 bpm) (20 male, 27 female; age 55±10 years) who both underwent dual-source CTCA and CCA were prospectively included in this study. All patients were performed CTCA using high pitch mode setting at 20%-30% of the R-R interval for the image acquisition. All coronary segments were evaluated by two blinded and independent observers with regard to image quality on a three-point scale (1: excellent to 3: non-diagnostic) and for the presence of significant coronary stenoses (defined as diameter narrowing exceeding 50%). Considered CCA as the standard of reference, the sensitivity, specificity, positive predictive value and negative predictive value were calculated. Radiation dose values were calculated using the dose-length product. Results Image quality was rated as being score 1 in 92.4% of segments, score 2 in 6.1% of segmentsand score 3 in 1.5% of segments. The average image quality score per segment was 1.064±0.306. The HR variability of patients with image score 1, 2 and 3 were 2.29±1.06 bpm, 5.17±1.37 bpm, 8.88±1.53 bpm, respectively. The average HR variability of patients with different image scores were significantly different (F=170.402, P=0.001). The sensitivity, specificity, positive and negative predictive values were 92.6%, 97.0%, 87.6%, 98.3%, respectively, per segment and 90.0%, 95.2%, 85.3%, 96.9%, respectively, per vessel and 100%, 63.6%, 90.0%, 100%, respectively, per patient. The effective radiation dose was on average 0.86±0.16 mSv. Conclusion In patients with HR more than 65 bpm and below 100 bpm without cardiac arrhythmia, the prospectively electrocardiogram-gated high-pitch spiral acquisition mode with image acquired timing set at 20%-30% of the R-R interval provides a high diagnostic accuracy for the assessment of coronary stenoses combined with a 1.5% of non-diagnostic coronary segments and a radiation dose below 1 mSv.
基金Supported by the Ministry of Science and Technology of Inner Mongolia, China (20110504)
文摘Objective To investigate the feasibility of acquiring the similar homogeneous enhancement using bolus-tracking techniques with shortened respiratory time in prospectively electrocardiogram-gated high-pitch spiral acquisition mode (Flash mode) coronary computed tomography angiography (CCTA) compared with test bolus technique. Methods One hundred and eighty-four consecutive patients with mean heart rate ≤65 beats per minute undergoing CCTA were prospectively included in this study. The patients were randomly divided into two groups. Patients in the group A (n=92) instructed to shorten respiratory time received CCTA using bolus-tracking technique with high-pitch spiral acquisition mode (Flash mode), while those in the group B (n=92) underwent CCTA with test bolus technique. The attenuation in the ascending aorta, image noise, contrast-to-noise ratio and radiation doses of the two groups were assessed. Results There were no significant differences in the mean attenuation values in the ascending aorta (483.18±59.07 HU vs. 498.7±83.51 HU, P=0.183), image noise (21.4±4.5 HU vs. 20.9±4.3 HU, P=0.414), contrast-to-noise ratio (12.1±4.2 vs. 13.8±5.1, P=0.31) between the groups A and B. There were no significant differences in the radiation dose of dynamic monitoring scans (0.056±0.026 mSv vs. 0.062±0.018 mSv, P=0.068) and radiation dose of angiography (0.94±0.07 mSv vs. 0.96±0.15 mSv,P=0.926) between the two groups, while 15 mL less contrast material volume was administered in the group A than the group B. Conclusion Bolus-tracking technique with shortened time of respiratory in Flash mode of dual-source CT yields the similar homogeneous enhancement with less contrast material in comparison to the test bolus technique.
基金The authors would like to thank X.Zhang,faculty of XinAoMDT Technology Co.,Ltd.,for the work of system software development.This work is supported by the National Natural Science Foundation of China under Grant Nos.81071191,60831003,30930092,30872633the Tsinghua-Yue-Yuen Medical Science Foundationthe National Basic Research Program of China(973)under Grant No.2011CB707701.
文摘We report on tests of combined positron emission tomography(PET)andfluorescence molecular tomography(FMT)imaging system for in vivo investigation on small animals.A nude mouse was inoculated with MD-MB-231 breast cancer cells which expressed redfluorescent protein(RFP).For FMT system,reflective illumination mode was adopted with full-angle data acquisition.[18F]-Fluorodeoxyglucose([18F]-FDG)was used as radioactive tracer for PET.Both data were acquired simultaneously and then reconstructed separately before fusion.Fluorescent tomography results showed exactly where the tumor was located while PET results offered more metabolic information.Results confirmed feasibility for tumor detection and showed superiority to single modality imaging.
文摘Objective: On the premise that the image quality meets the requirements of clinical diagnosis, we explored the methods to reduce the radiation dose of coronary artery imaging with Dual-Source CT (DSCT). Methods: We randomly selected 200 patients with coronary heat disease (BIM 0.05). The average image noise in group A is (41.76 ± 7.98) HU, in group B the average image noise is (43.97 ± 3.88) HU, the dif- ference between the two groups was not statistically significant (P>0.05). The average CTDIvol of group A and B were (20.63 ± 2.24) mGy, (38.11 ± 10.69) mGy, respectively, then P <0.01. The average DLP of group A and B are (235.75 ± 28.64) mGycm and (492.59 ± 125.49) mGycm respectively, then P <0.01, the dif- ference of radiation dose had statistical significance (P<0.05). Conclusions: For coronary artery imaging with DSCT the heart electric pulse (AUTO) regulation technology can meet the diagnostic requirements and effectively reduce the radiation dose.
文摘Photon-counting computed tomography(PCCT)represents a significant advancement in pediatric cardiovascular imaging.Traditional CT systems employ energy-integrating detectors that convert X-ray photons into visible light,whereas PCCT utilizes photon-counting detectors that directly transform X-ray photons into electric signals.This direct conversion allows photon-counting detectors to sort photons into discrete energy levels,thereby enhancing image quality through superior noise reduction,improved spatial and contrast resolution,and reduced artifacts.In pediatric applications,PCCT offers substantial benefits,including lower radiation doses,which may help reduce the risk of malignancy in pediatric patients,with perhaps greater potential to benefit those with repeated exposure from a young age.Enhanced spatial resolution facilitates better visualization of small structures,vital for diagnosing congenital heart defects.Additionally,PCCT’s spectral capabilities improve tissue characterization and enable the creation of virtual monoenergetic images,which enhance soft-tissue contrast and potentially reduce contrast media doses.Initial clinical results indicate that PCCT provides superior image quality and diagnostic accuracy compared to conven-tional CT,particularly in challenging pediatric cardiovascular cases.As PCCT technology matures,further research and standardized protocols will be essential to fully integrate it into pediatric imaging practices,ensuring optimized diagnostic outcomes and patient safety.
