The radiation dose received by patients undergoing chest radiography was included. 200 patients who attended these investigations in 10 hospitals in Iran were randomly selected from all ages groups and both female and...The radiation dose received by patients undergoing chest radiography was included. 200 patients who attended these investigations in 10 hospitals in Iran were randomly selected from all ages groups and both female and male. Critically ill patients were excluded. This paper presents the work, which was implemented on 200 patients and evaluated using the entrance skin dose （ESD） in the posterior anterior （PA） chest projection measured directly at the center of the X-ray field. In addition, the machine room, and dark room .parameters, as well as work practices and repeat rates were studied. The quality control （QC） parameters and the ESD before and after QC were evaluated utilizing an anthropomorphic phantom to define the optimal exposure condition at all hospitals. This research shows that after using the QC parameters and after optimization of the exposure conditions, the ESD was decreased by 42% on average. Also the qua/ity of the radiographs generally increased. The reported method is easily implemented in any clinical situation where optimization of chest radiography is needed.展开更多
BACKGROUND Coronary computed tomography angiography(CCTA)is the preferred noninvasive examination method for coronary heart disease.However,the radiation from computed tomography has become a concern since public awar...BACKGROUND Coronary computed tomography angiography(CCTA)is the preferred noninvasive examination method for coronary heart disease.However,the radiation from computed tomography has become a concern since public awareness of radiation hazards continue to increase.AIM To explore the value of multiple dose reduction techniques for CCTA.METHODS Consecutive normal and overweight patients were prospectively divided into two groups:Group A1,patients who received multiple dose reduction scans(n=82);and group A2,patients who received conventional scans(n=39).The scan parameters for group A1 were as follows:Isocentric scan,tube voltage=80 kV,and tube current control using 80%smart milliampere.The scan parameters for group A2 were as follows:Normal position,tube voltage=100 kV,and smart milliampere.RESULTS The average effective doses(EDs)for groups A1 and A2 were 1.13±0.35 and 3.36±1.30 mSv,respectively.There was a statistically significant difference in ED between the two groups(P<0.01).Furthermore,noise was significantly lower,and both signal-to-noise ratio and contrast signal-to-noise ratio were higher in group A2 when compared to group A1(P<0.01).Moreover,the subjective image quality(IQ)scores were excellent in both groups,in which there was no significant difference in subjective IQ score between the two groups(P=0.12).CONCLUSION Multiple dose reduction scan techniques can significantly decrease the ED of patients receiving CCTA examinations for clinical diagnosis.展开更多
Background：Contrast dose and radiation dose reduction in computerized tomography （CT） scan for adult has been explored successfully,but there have been few studies on the application of low-concentration contrast i...Background：Contrast dose and radiation dose reduction in computerized tomography （CT） scan for adult has been explored successfully,but there have been few studies on the application of low-concentration contrast in pediatric abdominal CT examinations.This was a feasibility study on the use of dual-energy spectral imaging and adaptive statistical iterative reconstruction （ASiR） for the reduction of radiation dose and iodine contrast dose in pediatric abdominal CT patients with solid tumors.Methods：Forty-five patients with solid tumors who had initial CT （Group B） and follow-up CT （Group A） after chemotherapy were enrolled.The initial diagnostic CT scan （Group B） was performed using the standard two-phase enhanced CT with 320 mgI/ml concentration contrast,and the follow-up scan （Group A） was performed using a single-phase enhanced CT at 45 s after the beginning of the 270 mgI/ml contrast injection using spectral mode.Forty percent ASiR was used for the images in Group B and monochromatic images with energy levels ≥60 keV in Group A.In addition,filtered back-projection （FBP） reconstruction was used for monochromatic images 〈60 keV in Group A.The total radiation dose,total iodine load,contrast injection speed,and maximum injection pressure were compared between the two groups.The 40 keV and 60 keV spectral CT images of Group A were compared with the images of Group B to evaluate overall image quality.Results：The total radiation dose,total iodine load,injection speed,and maximum injection pressure for Group A were decreased by 19%,15%,34.4%,and 18.3%,respectively.The optimal energy level in spectral CT for displaying the abdominal vessels was 40 keV.At this level,the CT values in the abdominal aorta and its three branches,the portal vein and its two branches,and the inferior vena cava were all greater than 340 hounsfield unit （HU）.The abdominal organs of Groups A and B had similar degrees of absolute and relative enhancement （t =0.36 and-1.716 for liver,0.153 and-1.546 for pancreas,and 2.427 and 0.866 for renal cortex,all P 〉 0.05）.Signal-to-noise ratio of the abdominal organs was significantly lower in Group A than in Group B （t =-8.11 for liver,-7.83 for pancreas,and-5.38 for renal cortex,all P 〈 0.05）.However,the subjective scores for the 40 keV （FBP） and 60 keV （40% ASiR） spectral CT images determined by two radiologists were all 〉3,indicating clinically acceptable image quality.Conclusions：Single-phase,dual-energy spectral CT used for children with solid abdominal tumors can reduce contrast dose and radiation dose and can also maintain clinically acceptable image quality.展开更多
AIM To evaluate the feasibility of reducing the dose of iodinated contrast agent in computed tomography pulmonary angiography(CTPA). METHODS One hundred and twenty-seven patients clinically suspected of having pulmona...AIM To evaluate the feasibility of reducing the dose of iodinated contrast agent in computed tomography pulmonary angiography(CTPA). METHODS One hundred and twenty-seven patients clinically suspected of having pulmonary embolism underwent spiral CTPA, out of whom fifty-seven received 75 mL and the remaining seventy a lower dose of 60 mL of contrast agent. Both doses were administered in a multiphasic injection. A minimum opacification threshold of 250 Hounsfield units(HU) in the main pulmonary artery is used for assessing the technical adequacy of the scans. RESULTS Mean opacification was found to be positively correlated to patient age(Pearson's correlation 0.4255, P < 0.0001) and independent of gender(male:female, 425.6 vs 450.4,P = 0.34). When age is accounted for, the study and control groups did not differ significantly in their mean opacification in the main(436.8 vs 437.9, P = 0.48),left(416.6 vs 419.8, P = 0.45) or the right pulmonary arteries(417.3 vs 423.5, P = 0.40). The number of sub-optimally opacified scans(the mean opacification in the main pulmonary artery < 250 HU) did not differ significantly between the study and control groups(7 vs 10).CONCLUSION A lower dose of iodine contrast at 60 mL can be feasibly used in CTPA without resulting in a higher number of sub-optimally opacified scans.展开更多
<strong>Background: </strong>Numerous studies have demonstrated increasing evidence for cataractogenesis at lower levels of ionizing radiation than previously believed, with some suggesting possible absenc...<strong>Background: </strong>Numerous studies have demonstrated increasing evidence for cataractogenesis at lower levels of ionizing radiation than previously believed, with some suggesting possible absence of a threshold. Genetic differences between individuals also result in increased susceptibility in some operators, who might not be aware. European occupational exposure limits have been reduced and operators are seeking protective measures. <strong>Objective: </strong>To evaluate the protective effect of a face-shield equipped suspended protection system (Zero-Gravity<span style="white-space:nowrap;"><sup><span style="white-space:nowrap;">®</span></sup></span>, TIDI Products, Neenah, WI) along with adherence to safety practices against radiation dose to the eye lens for an interventional radiologist performing a wide variety of procedures. <strong>Materials and Methods:</strong> In this institutional review board-approved single-institution study, one interventional radiologist wore a highly sensitive personnel monitoring dosimeter badge on the cap near the left eye while performing 299 procedures (3690 fluoroscopy minutes) over 18 consecutive months while utilizing the suspended protection system along with adherence to other generally recommended safety practices and movement away from the field during angiographic power injections. Dosimetry reports and procedural information were retrospectively reviewed. <strong>Results: </strong>Total lens dose equivalent to the left eye over 18 months was 0.11 mSv (annualized dose = 0.073 mSv, or 7.3 mRem). The patient-dose-area product standardized dose of 0.00576 <span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">μ</span></span></span>Sv/Gy<span style="white-space:nowrap;"><span style="white-space:nowrap;">⋅</span></span>cm<sup>2</sup> is well below reports of conventional lead aprons, shields, and protective eyewear. <strong>Conclusion: </strong>Eye exposures were kept to near-background levels using the materials and methods of this study while performing a wide variety of complex procedures from all positions around the patient.展开更多
BACKGROUND Photon-counting detector(PCD)CT represents a transformative advancement in radiological imaging,offering superior spatial resolution,enhanced contrast-tonoise ratio,and reduced radiation dose compared with ...BACKGROUND Photon-counting detector(PCD)CT represents a transformative advancement in radiological imaging,offering superior spatial resolution,enhanced contrast-tonoise ratio,and reduced radiation dose compared with the conventional energyintegrating detector CT.AIM To evaluate PCD CT in oncologic imaging,focusing on its role in tumor detection,staging,and treatment response assessment.METHODS We performed a systematic PubMed search from January 1,2017 to December 31,2024,using the keywords“photon-counting CT”,“cancer”,and“tumor”to identify studies on its use in oncologic imaging.We included experimental studies on humans or human phantoms and excluded reviews,commentaries,editorials,non-English,animal,and non-experimental studies.Study selection followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Out of 175 initial studies,39 met the inclusion criteria after screening and full-text review.Data extraction focused on study type,country of origin,and oncologic applications of photon-counting CT.No formal risk of bias assessment was performed,and the review was not registered in PROSPERO as it did not include a meta-analysis.RESULTS Key findings highlighted the advantages of PCD CT in imaging renal masses,adrenal adenomas,ovarian cancer,breast cancer,prostate cancer,pancreatic tumors,hepatocellular carcinoma,metastases,multiple myeloma,and lung cancer.Additionally,PCD CT has demonstrated improved lesion characterization and enhanced diagnostic accuracy in oncology.Despite its promising capabilities challenges related to data processing,storage,and accessibility remain.CONCLUSION As PCD CT technology evolves,its integration into routine oncologic imaging has the potential to significantly enhance cancer diagnosis and patient management.展开更多
Background:Quantum-enhanced medical imaging algorithms–quantum entanglement reconstruction,quantum noise suppression,and quantum beamforming–propose possible remedies for significant constraints in traditional diagn...Background:Quantum-enhanced medical imaging algorithms–quantum entanglement reconstruction,quantum noise suppression,and quantum beamforming–propose possible remedies for significant constraints in traditional diagnostic imaging,such as resolution,radiation efficiency,and real-time processing.Methods:This work used a mixed-methods strategy,including controlled phantom experiments,retrospective multi-center clinical data analysis,and quantum-classical hybrid processing to assess enhancements in resolution,dosage efficiency,and diagnostic confidence.Statistical validation included analysis of variance(ANOVA)and receiver-operating characteristic curve analysis,juxtaposing quantum-enhanced methodologies with conventional and deep learning approaches.Results:Quantum entanglement reconstruction enhanced magnetic resonance imaging spatial resolution by 33.2%(P<0.01),quantum noise suppression facilitated computed tomography scans with a 60%reduction in radiation,and quantum beamforming improved ultrasound contrast by 27%while preserving real-time processing(<2 ms delay).Inter-reader variability(12%in Diagnostic Confidence Scores)showed that systematic training is needed,even if the performance was better.The research presented(1)a reusable clinical quantum imaging framework,(2)enhanced hardware processes(field-programmable gate array/graphics processing unit acceleration),and(3)cost-benefit analyses demonstrating a 22-month return on investment breakeven point.Conclusion:Quantum-enhanced imaging has a lot of promise for use in medicine,especially in neurology and cancer.Future research should focus on multi-modal integration(e.g.,positron emission tomography–magnetic resonance imaging),cloud-based quantum simulations for enhanced accessibility,and extensive trials to confirm long-term diagnostic accuracy.This breakthrough gives healthcare systems a technology roadmap and a reason to spend money on quantum-enhanced diagnostics.展开更多
For cone beam computed tomography(CBCT),there has long been a desire to modulate the intensity and distribution of the X-rays to accommodate the patient’s anatomy as the gantry rotates from one projection to another....For cone beam computed tomography(CBCT),there has long been a desire to modulate the intensity and distribution of the X-rays to accommodate the patient’s anatomy as the gantry rotates from one projection to another.This would reduce both image artifacts and radiation dose.However,the current beam modulation setups,such as dynamic bowtie filters,may be too complex for practical use in clinical applications.This study aimed to investigate a simplified dynamic beam filtration strategy for CBCT imaging to reduce image artifacts and radiation dose.In this study,the beam filtration was designed to vary dynamically as the CBCT gantry rotates around the object.Specifically,two distinct components were integrated:the sheet filter part and the bowtie filter part.The dynamic beam filtration setup has two working schemes,one is a combination of dynamic sheet filter and dynamic bowtie filter,denoted as dynamic filterdynamic bowtie(DFDB);the other is a combination of dynamic sheet filter and static bowtie filter,denoted as dynamic filter-static bowtie(DFSB).Numerical imaging experiments were performed for three human body parts:the shoulder,chest,and knee.In addition,the Monte Carlo simulation platform MC-GPU was used to generate the dose distribution maps.Results showed that the proposed DFDB and DFSB beam filtration schemes can significantly reduce the image artifacts and thus improve the CBCT image quality.Depending on the scanned object,the total radiation dose could be reduced by 30%.The proposed simple dynamic beam filtration strategy,especially the DFSB approach,could be beneficial in the future to improve the CBCT image quality with reduced image artifacts and radiation dose.展开更多
In this report,acupoint embedding method was used for a 25-year-old female patient with epilepsy.The patient suffered from repeated paroxysmal unconsciousness combined with convulsions of four limbs for13 years,and ex...In this report,acupoint embedding method was used for a 25-year-old female patient with epilepsy.The patient suffered from repeated paroxysmal unconsciousness combined with convulsions of four limbs for13 years,and exacerbation for 2 months.She was orally administered with antiepileptic drugs which showed poor control.Using the treatment principles of regulating the mind,opening the orifices,extinguishing wind,and relieving epilepsy,suture-embedded acupoints include Dàzhuī(大椎GV14),Bǎihuì(百会GV20),Xuánlú(悬颅GB5),Yāoqí(腰奇EX-B9),Gānshū(肝俞BL18),Jiūwěi(鸠尾CV15),Jiānshǐ(间使PC5),and Fēnglóng(丰隆ST40),and the patient was treated once a month(qw).After treatment for 6 times,the patient had occasionally a seizure that lasted for several seconds,and the patient’s condition was improved obviously.Acupoint embedding method can control the frequency of epileptic seizures effectively,and reduce the dose of antiepileptic drugs,and deserves further research.展开更多
BACKGROUND Diabesity(diabetes as a consequence of obesity)has emerged as a huge healthcare challenge across the globe due to the obesity pandemic.Judicious use of antidiabetic medications including semaglutide is impo...BACKGROUND Diabesity(diabetes as a consequence of obesity)has emerged as a huge healthcare challenge across the globe due to the obesity pandemic.Judicious use of antidiabetic medications including semaglutide is important for optimal management of diabesity as proven by multiple randomized controlled trials.However,more real-world data is needed to further improve the clinical practice.AIM To study the real-world benefits and side effects of using semaglutide to manage patients with diabesity.METHODS We evaluated the efficacy and safety of semaglutide use in managing patients with diabesity in a large academic hospital in the United States.Several parameters were analyzed including demographic information,the data on improvement of glycated hemoglobin(HbA1c),body weight reduction and insulin dose adjustments at 6 and 12 months,as well as at the latest follow up period.The data was obtained from the electronic patient records between January 2019 to May 2023.RESULTS 106 patients(56 males)with type 2 diabetes mellitus(T2DM),mean age 60.8±11.2 years,mean durations of T2DM 12.4±7.2 years and mean semaglutide treatment for 2.6±1.1 years were included.Semaglutide treatment was associated with significant improvement in diabesity outcomes such as mean weight reductions from baseline 110.4±24.6 kg to 99.9±24.9 kg at 12 months and 96.8±22.9 kg at latest follow up and HbA1c improvement from baseline of 82±21 mmol/mol to 67±20 at 12 months and 71±23 mmol/mol at the latest follow up.An insulin dose reduction from mean baseline of 95±74 units to 76.5±56.2 units was also observed at the latest follow up.Side effects were mild and mainly gastrointestinal like bloating and nausea improving with prolonged use of semaglutide.CONCLUSION Semaglutide treatment is associated with significant improvement in diabesity outcomes such as reduction in body weight,HbA1c and insulin doses without major adverse effects.Reviews of largescale real-world data are expected to inform better clinical practice decision making to improve the care of patients with diabesity.展开更多
Selective Catalyst Reduction（SCR）Urea Dosing System（UDS）directly affects the system accuracy and the dynamic response performance of a vehicle.However,the UDS dynamic response is hard to keep up with the changes o...Selective Catalyst Reduction（SCR）Urea Dosing System（UDS）directly affects the system accuracy and the dynamic response performance of a vehicle.However,the UDS dynamic response is hard to keep up with the changes of the engine＇s operating conditions.That will lead to low NO_χconversion efficiency or NH_3 slip.In order to optimize the injection accuracy and the response speed of the UDS in dynamic conditions,an advanced control strategy based on an air-assisted volumetric UDS is presented.It covers the methods of flow compensation and switching working conditions.The strategy is authenticated on an UDS and tested in different dynamic conditions.The result shows that the control strategy discussed results in higher dynamic accuracy and faster dynamic response speed of UDS.The inject deviation range is improved from being between-8%and 10%to-4%and 2%and became more stable than before,and the dynamic response time was shortened from 200 ms to 150 ms.The ETC cycle result shows that after using the new strategy the NH_3 emission is reduced by 60%,and the NO_χemission remains almost unchanged.The trade-off between NO_χconversion efficiency and NH_3 slip is mitigated.The studied flow compensation and switching working conditions can improve the dynamic performance of the UDS significantly and make the UDS dynamic response keep up with the changes of the engine＇s operating conditions quickly.展开更多
Background:Rheumatoid arthritis(RA),a chronic systemic autoimmune disease,is characterized by synovitis and progressive damage to the bone and cartilage of the joints,leading to disability and reduced quality of life....Background:Rheumatoid arthritis(RA),a chronic systemic autoimmune disease,is characterized by synovitis and progressive damage to the bone and cartilage of the joints,leading to disability and reduced quality of life.This study was a randomized clinical trial comparing the outcomes between withdrawal and dose reduction of tofacitinib in patients with RA who achieved sustained disease control.Methods:The study was designed as a multicenter,open-label,randomized controlled trial.Eligible patients who were taking tofacitinib(5 mg twice daily)and had achieved sustained RA remission or low disease activity(disease activity score in 28 joints[DAS28]≤3.2)for at least 3 months were enrolled at six centers in Shanghai,China.Patients were randomly assigned(1:1:1)to one of three treatment groups:continuation of tofacitinib(5 mg twice daily);reduction in tofacitinib dose(5 mg daily);and withdrawal of tofacitinib.Efficacy and safety were assessed up to 6 months.Results:Overall,122 eligible patients were enrolled,with 41 in the continuation group,42 in the dose-reduction group,and 39 in the withdrawal group.After 6 months,the percentage of patients with a DAS28-erythrocyte sedimentation rate(ESR)of<3.2 was significantly lower in the withdrawal group than that in the reduction and continuation groups(20.5%,64.3%,and 95.1%,respectively;P<0.0001 for both comparisons).The average flare-free time was 5.8 months for the continuation group,4.7 months for the dose reduction group,and 2.4 months for the withdrawal group.Conclusion:Withdrawal of tofacitinib in patients with RA with stable disease control resulted in a rapid and significant loss of efficacy,while standard or reduced doses of tofacitinib maintained a favorable state.Trial Registration:Chictr.org,ChiCTR2000039799.展开更多
文摘The radiation dose received by patients undergoing chest radiography was included. 200 patients who attended these investigations in 10 hospitals in Iran were randomly selected from all ages groups and both female and male. Critically ill patients were excluded. This paper presents the work, which was implemented on 200 patients and evaluated using the entrance skin dose （ESD） in the posterior anterior （PA） chest projection measured directly at the center of the X-ray field. In addition, the machine room, and dark room .parameters, as well as work practices and repeat rates were studied. The quality control （QC） parameters and the ESD before and after QC were evaluated utilizing an anthropomorphic phantom to define the optimal exposure condition at all hospitals. This research shows that after using the QC parameters and after optimization of the exposure conditions, the ESD was decreased by 42% on average. Also the qua/ity of the radiographs generally increased. The reported method is easily implemented in any clinical situation where optimization of chest radiography is needed.
基金Supported by Zhuhai Medical Research Fund,No.ZH3310200001PJL.
文摘BACKGROUND Coronary computed tomography angiography(CCTA)is the preferred noninvasive examination method for coronary heart disease.However,the radiation from computed tomography has become a concern since public awareness of radiation hazards continue to increase.AIM To explore the value of multiple dose reduction techniques for CCTA.METHODS Consecutive normal and overweight patients were prospectively divided into two groups:Group A1,patients who received multiple dose reduction scans(n=82);and group A2,patients who received conventional scans(n=39).The scan parameters for group A1 were as follows:Isocentric scan,tube voltage=80 kV,and tube current control using 80%smart milliampere.The scan parameters for group A2 were as follows:Normal position,tube voltage=100 kV,and smart milliampere.RESULTS The average effective doses(EDs)for groups A1 and A2 were 1.13±0.35 and 3.36±1.30 mSv,respectively.There was a statistically significant difference in ED between the two groups(P<0.01).Furthermore,noise was significantly lower,and both signal-to-noise ratio and contrast signal-to-noise ratio were higher in group A2 when compared to group A1(P<0.01).Moreover,the subjective image quality(IQ)scores were excellent in both groups,in which there was no significant difference in subjective IQ score between the two groups(P=0.12).CONCLUSION Multiple dose reduction scan techniques can significantly decrease the ED of patients receiving CCTA examinations for clinical diagnosis.
文摘Background：Contrast dose and radiation dose reduction in computerized tomography （CT） scan for adult has been explored successfully,but there have been few studies on the application of low-concentration contrast in pediatric abdominal CT examinations.This was a feasibility study on the use of dual-energy spectral imaging and adaptive statistical iterative reconstruction （ASiR） for the reduction of radiation dose and iodine contrast dose in pediatric abdominal CT patients with solid tumors.Methods：Forty-five patients with solid tumors who had initial CT （Group B） and follow-up CT （Group A） after chemotherapy were enrolled.The initial diagnostic CT scan （Group B） was performed using the standard two-phase enhanced CT with 320 mgI/ml concentration contrast,and the follow-up scan （Group A） was performed using a single-phase enhanced CT at 45 s after the beginning of the 270 mgI/ml contrast injection using spectral mode.Forty percent ASiR was used for the images in Group B and monochromatic images with energy levels ≥60 keV in Group A.In addition,filtered back-projection （FBP） reconstruction was used for monochromatic images 〈60 keV in Group A.The total radiation dose,total iodine load,contrast injection speed,and maximum injection pressure were compared between the two groups.The 40 keV and 60 keV spectral CT images of Group A were compared with the images of Group B to evaluate overall image quality.Results：The total radiation dose,total iodine load,injection speed,and maximum injection pressure for Group A were decreased by 19%,15%,34.4%,and 18.3%,respectively.The optimal energy level in spectral CT for displaying the abdominal vessels was 40 keV.At this level,the CT values in the abdominal aorta and its three branches,the portal vein and its two branches,and the inferior vena cava were all greater than 340 hounsfield unit （HU）.The abdominal organs of Groups A and B had similar degrees of absolute and relative enhancement （t =0.36 and-1.716 for liver,0.153 and-1.546 for pancreas,and 2.427 and 0.866 for renal cortex,all P 〉 0.05）.Signal-to-noise ratio of the abdominal organs was significantly lower in Group A than in Group B （t =-8.11 for liver,-7.83 for pancreas,and-5.38 for renal cortex,all P 〈 0.05）.However,the subjective scores for the 40 keV （FBP） and 60 keV （40% ASiR） spectral CT images determined by two radiologists were all 〉3,indicating clinically acceptable image quality.Conclusions：Single-phase,dual-energy spectral CT used for children with solid abdominal tumors can reduce contrast dose and radiation dose and can also maintain clinically acceptable image quality.
文摘AIM To evaluate the feasibility of reducing the dose of iodinated contrast agent in computed tomography pulmonary angiography(CTPA). METHODS One hundred and twenty-seven patients clinically suspected of having pulmonary embolism underwent spiral CTPA, out of whom fifty-seven received 75 mL and the remaining seventy a lower dose of 60 mL of contrast agent. Both doses were administered in a multiphasic injection. A minimum opacification threshold of 250 Hounsfield units(HU) in the main pulmonary artery is used for assessing the technical adequacy of the scans. RESULTS Mean opacification was found to be positively correlated to patient age(Pearson's correlation 0.4255, P < 0.0001) and independent of gender(male:female, 425.6 vs 450.4,P = 0.34). When age is accounted for, the study and control groups did not differ significantly in their mean opacification in the main(436.8 vs 437.9, P = 0.48),left(416.6 vs 419.8, P = 0.45) or the right pulmonary arteries(417.3 vs 423.5, P = 0.40). The number of sub-optimally opacified scans(the mean opacification in the main pulmonary artery < 250 HU) did not differ significantly between the study and control groups(7 vs 10).CONCLUSION A lower dose of iodine contrast at 60 mL can be feasibly used in CTPA without resulting in a higher number of sub-optimally opacified scans.
文摘<strong>Background: </strong>Numerous studies have demonstrated increasing evidence for cataractogenesis at lower levels of ionizing radiation than previously believed, with some suggesting possible absence of a threshold. Genetic differences between individuals also result in increased susceptibility in some operators, who might not be aware. European occupational exposure limits have been reduced and operators are seeking protective measures. <strong>Objective: </strong>To evaluate the protective effect of a face-shield equipped suspended protection system (Zero-Gravity<span style="white-space:nowrap;"><sup><span style="white-space:nowrap;">®</span></sup></span>, TIDI Products, Neenah, WI) along with adherence to safety practices against radiation dose to the eye lens for an interventional radiologist performing a wide variety of procedures. <strong>Materials and Methods:</strong> In this institutional review board-approved single-institution study, one interventional radiologist wore a highly sensitive personnel monitoring dosimeter badge on the cap near the left eye while performing 299 procedures (3690 fluoroscopy minutes) over 18 consecutive months while utilizing the suspended protection system along with adherence to other generally recommended safety practices and movement away from the field during angiographic power injections. Dosimetry reports and procedural information were retrospectively reviewed. <strong>Results: </strong>Total lens dose equivalent to the left eye over 18 months was 0.11 mSv (annualized dose = 0.073 mSv, or 7.3 mRem). The patient-dose-area product standardized dose of 0.00576 <span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">μ</span></span></span>Sv/Gy<span style="white-space:nowrap;"><span style="white-space:nowrap;">⋅</span></span>cm<sup>2</sup> is well below reports of conventional lead aprons, shields, and protective eyewear. <strong>Conclusion: </strong>Eye exposures were kept to near-background levels using the materials and methods of this study while performing a wide variety of complex procedures from all positions around the patient.
文摘BACKGROUND Photon-counting detector(PCD)CT represents a transformative advancement in radiological imaging,offering superior spatial resolution,enhanced contrast-tonoise ratio,and reduced radiation dose compared with the conventional energyintegrating detector CT.AIM To evaluate PCD CT in oncologic imaging,focusing on its role in tumor detection,staging,and treatment response assessment.METHODS We performed a systematic PubMed search from January 1,2017 to December 31,2024,using the keywords“photon-counting CT”,“cancer”,and“tumor”to identify studies on its use in oncologic imaging.We included experimental studies on humans or human phantoms and excluded reviews,commentaries,editorials,non-English,animal,and non-experimental studies.Study selection followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Out of 175 initial studies,39 met the inclusion criteria after screening and full-text review.Data extraction focused on study type,country of origin,and oncologic applications of photon-counting CT.No formal risk of bias assessment was performed,and the review was not registered in PROSPERO as it did not include a meta-analysis.RESULTS Key findings highlighted the advantages of PCD CT in imaging renal masses,adrenal adenomas,ovarian cancer,breast cancer,prostate cancer,pancreatic tumors,hepatocellular carcinoma,metastases,multiple myeloma,and lung cancer.Additionally,PCD CT has demonstrated improved lesion characterization and enhanced diagnostic accuracy in oncology.Despite its promising capabilities challenges related to data processing,storage,and accessibility remain.CONCLUSION As PCD CT technology evolves,its integration into routine oncologic imaging has the potential to significantly enhance cancer diagnosis and patient management.
文摘Background:Quantum-enhanced medical imaging algorithms–quantum entanglement reconstruction,quantum noise suppression,and quantum beamforming–propose possible remedies for significant constraints in traditional diagnostic imaging,such as resolution,radiation efficiency,and real-time processing.Methods:This work used a mixed-methods strategy,including controlled phantom experiments,retrospective multi-center clinical data analysis,and quantum-classical hybrid processing to assess enhancements in resolution,dosage efficiency,and diagnostic confidence.Statistical validation included analysis of variance(ANOVA)and receiver-operating characteristic curve analysis,juxtaposing quantum-enhanced methodologies with conventional and deep learning approaches.Results:Quantum entanglement reconstruction enhanced magnetic resonance imaging spatial resolution by 33.2%(P<0.01),quantum noise suppression facilitated computed tomography scans with a 60%reduction in radiation,and quantum beamforming improved ultrasound contrast by 27%while preserving real-time processing(<2 ms delay).Inter-reader variability(12%in Diagnostic Confidence Scores)showed that systematic training is needed,even if the performance was better.The research presented(1)a reusable clinical quantum imaging framework,(2)enhanced hardware processes(field-programmable gate array/graphics processing unit acceleration),and(3)cost-benefit analyses demonstrating a 22-month return on investment breakeven point.Conclusion:Quantum-enhanced imaging has a lot of promise for use in medicine,especially in neurology and cancer.Future research should focus on multi-modal integration(e.g.,positron emission tomography–magnetic resonance imaging),cloud-based quantum simulations for enhanced accessibility,and extensive trials to confirm long-term diagnostic accuracy.This breakthrough gives healthcare systems a technology roadmap and a reason to spend money on quantum-enhanced diagnostics.
文摘For cone beam computed tomography(CBCT),there has long been a desire to modulate the intensity and distribution of the X-rays to accommodate the patient’s anatomy as the gantry rotates from one projection to another.This would reduce both image artifacts and radiation dose.However,the current beam modulation setups,such as dynamic bowtie filters,may be too complex for practical use in clinical applications.This study aimed to investigate a simplified dynamic beam filtration strategy for CBCT imaging to reduce image artifacts and radiation dose.In this study,the beam filtration was designed to vary dynamically as the CBCT gantry rotates around the object.Specifically,two distinct components were integrated:the sheet filter part and the bowtie filter part.The dynamic beam filtration setup has two working schemes,one is a combination of dynamic sheet filter and dynamic bowtie filter,denoted as dynamic filterdynamic bowtie(DFDB);the other is a combination of dynamic sheet filter and static bowtie filter,denoted as dynamic filter-static bowtie(DFSB).Numerical imaging experiments were performed for three human body parts:the shoulder,chest,and knee.In addition,the Monte Carlo simulation platform MC-GPU was used to generate the dose distribution maps.Results showed that the proposed DFDB and DFSB beam filtration schemes can significantly reduce the image artifacts and thus improve the CBCT image quality.Depending on the scanned object,the total radiation dose could be reduced by 30%.The proposed simple dynamic beam filtration strategy,especially the DFSB approach,could be beneficial in the future to improve the CBCT image quality with reduced image artifacts and radiation dose.
基金Supported by Henan leading talents plan project:HNZYLJ201301008
文摘In this report,acupoint embedding method was used for a 25-year-old female patient with epilepsy.The patient suffered from repeated paroxysmal unconsciousness combined with convulsions of four limbs for13 years,and exacerbation for 2 months.She was orally administered with antiepileptic drugs which showed poor control.Using the treatment principles of regulating the mind,opening the orifices,extinguishing wind,and relieving epilepsy,suture-embedded acupoints include Dàzhuī(大椎GV14),Bǎihuì(百会GV20),Xuánlú(悬颅GB5),Yāoqí(腰奇EX-B9),Gānshū(肝俞BL18),Jiūwěi(鸠尾CV15),Jiānshǐ(间使PC5),and Fēnglóng(丰隆ST40),and the patient was treated once a month(qw).After treatment for 6 times,the patient had occasionally a seizure that lasted for several seconds,and the patient’s condition was improved obviously.Acupoint embedding method can control the frequency of epileptic seizures effectively,and reduce the dose of antiepileptic drugs,and deserves further research.
文摘BACKGROUND Diabesity(diabetes as a consequence of obesity)has emerged as a huge healthcare challenge across the globe due to the obesity pandemic.Judicious use of antidiabetic medications including semaglutide is important for optimal management of diabesity as proven by multiple randomized controlled trials.However,more real-world data is needed to further improve the clinical practice.AIM To study the real-world benefits and side effects of using semaglutide to manage patients with diabesity.METHODS We evaluated the efficacy and safety of semaglutide use in managing patients with diabesity in a large academic hospital in the United States.Several parameters were analyzed including demographic information,the data on improvement of glycated hemoglobin(HbA1c),body weight reduction and insulin dose adjustments at 6 and 12 months,as well as at the latest follow up period.The data was obtained from the electronic patient records between January 2019 to May 2023.RESULTS 106 patients(56 males)with type 2 diabetes mellitus(T2DM),mean age 60.8±11.2 years,mean durations of T2DM 12.4±7.2 years and mean semaglutide treatment for 2.6±1.1 years were included.Semaglutide treatment was associated with significant improvement in diabesity outcomes such as mean weight reductions from baseline 110.4±24.6 kg to 99.9±24.9 kg at 12 months and 96.8±22.9 kg at latest follow up and HbA1c improvement from baseline of 82±21 mmol/mol to 67±20 at 12 months and 71±23 mmol/mol at the latest follow up.An insulin dose reduction from mean baseline of 95±74 units to 76.5±56.2 units was also observed at the latest follow up.Side effects were mild and mainly gastrointestinal like bloating and nausea improving with prolonged use of semaglutide.CONCLUSION Semaglutide treatment is associated with significant improvement in diabesity outcomes such as reduction in body weight,HbA1c and insulin doses without major adverse effects.Reviews of largescale real-world data are expected to inform better clinical practice decision making to improve the care of patients with diabesity.
基金Supported by National Hi-tech Research and Development Program of China(863 Program,Grant No.2012AA111708)
文摘Selective Catalyst Reduction（SCR）Urea Dosing System（UDS）directly affects the system accuracy and the dynamic response performance of a vehicle.However,the UDS dynamic response is hard to keep up with the changes of the engine＇s operating conditions.That will lead to low NO_χconversion efficiency or NH_3 slip.In order to optimize the injection accuracy and the response speed of the UDS in dynamic conditions,an advanced control strategy based on an air-assisted volumetric UDS is presented.It covers the methods of flow compensation and switching working conditions.The strategy is authenticated on an UDS and tested in different dynamic conditions.The result shows that the control strategy discussed results in higher dynamic accuracy and faster dynamic response speed of UDS.The inject deviation range is improved from being between-8%and 10%to-4%and 2%and became more stable than before,and the dynamic response time was shortened from 200 ms to 150 ms.The ETC cycle result shows that after using the new strategy the NH_3 emission is reduced by 60%,and the NO_χemission remains almost unchanged.The trade-off between NO_χconversion efficiency and NH_3 slip is mitigated.The studied flow compensation and switching working conditions can improve the dynamic performance of the UDS significantly and make the UDS dynamic response keep up with the changes of the engine＇s operating conditions quickly.
文摘Background:Rheumatoid arthritis(RA),a chronic systemic autoimmune disease,is characterized by synovitis and progressive damage to the bone and cartilage of the joints,leading to disability and reduced quality of life.This study was a randomized clinical trial comparing the outcomes between withdrawal and dose reduction of tofacitinib in patients with RA who achieved sustained disease control.Methods:The study was designed as a multicenter,open-label,randomized controlled trial.Eligible patients who were taking tofacitinib(5 mg twice daily)and had achieved sustained RA remission or low disease activity(disease activity score in 28 joints[DAS28]≤3.2)for at least 3 months were enrolled at six centers in Shanghai,China.Patients were randomly assigned(1:1:1)to one of three treatment groups:continuation of tofacitinib(5 mg twice daily);reduction in tofacitinib dose(5 mg daily);and withdrawal of tofacitinib.Efficacy and safety were assessed up to 6 months.Results:Overall,122 eligible patients were enrolled,with 41 in the continuation group,42 in the dose-reduction group,and 39 in the withdrawal group.After 6 months,the percentage of patients with a DAS28-erythrocyte sedimentation rate(ESR)of<3.2 was significantly lower in the withdrawal group than that in the reduction and continuation groups(20.5%,64.3%,and 95.1%,respectively;P<0.0001 for both comparisons).The average flare-free time was 5.8 months for the continuation group,4.7 months for the dose reduction group,and 2.4 months for the withdrawal group.Conclusion:Withdrawal of tofacitinib in patients with RA with stable disease control resulted in a rapid and significant loss of efficacy,while standard or reduced doses of tofacitinib maintained a favorable state.Trial Registration:Chictr.org,ChiCTR2000039799.
