1.CT metal artifact correction using conditional diffusion model
Peiwen LIANG ; Mengxun ZHENG ; Long TANG ; Hua ZHANG
Chinese Journal of Medical Physics 2025;42(4):457-465
Objective To propose a conditional diffusion model based on template priors for correcting streaky metal artifacts characterized by alternating bright and dark patterns that appear in reconstructed computed tomography(CT)images due to the presence of metallic implants.Methods After isolating metal region using image segmentation technology to generate metal trajectory projection data,the projection data of metal trajectory and the corresponding projection data of template prior images were excluded.Subsequently,a conditional diffusion model was developed to recover the missing portions of the projection data in the metal-affected regions.Finally,the restored projection data were reconstructed using filtered back projection to obtain the corrected image.Results Compared with artifact disentanglement network and diffusion model,the proposed approach improved peak signal to noise ratio by 3.44 and 0.749 dB,and increased structural similarity index by 0.079 and 0.015,respectively.Conclusion The proposed approach outperforms traditional metal artifact correction methods and exhibits superior performance in reducing both streaky and shadow artifacts.
2.The characteristics and associated factors of hand dysfunction in patients with rheumatoid arthritis
Yaowei ZOU ; Ying YANG ; Zhiming OUYANG ; Jie PAN ; Peiwen JIA ; Kuimin YANG ; Huwei ZHENG ; Tao WU ; Jianzi LIN ; Jianda MA ; Yingqian MO ; Lie DAI
Chinese Journal of Internal Medicine 2025;64(2):119-127
Objective:To investigate the characteristics of hand dysfunction and its associated factors in patients with rheumatoid arthritis (RA).Methods:A cross-sectional study. Patients with RA were recruited from January 2019 to April 2024 at the Department of Rheumatology and Immunology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University. Demographic and clinical data were collected, including age, gender, active smoking, disease duration, time of morning stiffness, rheumatoid factor and anti-cyclic citrullinated peptide antibody, disease activity, radiographic indicators, and hand function assessment. Hand function was assessed by grip strength measures and self-reported items related to hand function in the Stanford Health Assessment Questionnaire. Factors related to hand function were analyzed by logistic regression analyses.Results:A total of 1 079 RA patients were recruited [mean age: (53.0±12.6) years]. Overall, 72.6% (783/1 079) patients experienced a decrease in grip strength, 57.2% (617/1 079) patients experienced a decreased grip strength in both hands, with the average grip strength of the left and right hands decreasing by 16.3% and 14.1%, respectively, compared to normal values; 39.9% (430/1 079) patients had self-reported hand dysfunction. There were 185 (17.1%) older RA patients (age ≥65 years). The proportion of older RA patients with decreased grip strength [89.7% (166/185) vs. 69.0% (617/894)] and degree of decrease in grip strength compared to normal values (left hand:-35.3%±30.6% vs. -12.3%±38.6%; right hand:-32.6%±32.3% vs. -10.3%±42.1%) were significantly higher than that in young patients, and the proportion of older patients with self-reported hand dysfunction was also significantly higher [53.0% (98/185) vs. 37.1% (332/894), all P<0.001]. Multivariate logistic regression analysis showed that pain visual analogue scale ( OR=1.375, 95% CI 1.020-1.854) was independently associated with grip strength decrease in older RA patients, while the 28-joint tender joint count ( OR=1.151, 95% CI 1.063-1.246) and provider global assessment of disease activity ( OR=1.381, 95% CI 1.171-1.628) were associated with self-reported hand dysfunction. Conclusions:Hand dysfunction is common in RA patients, especially among older RA patients, which is related to pain, joint tenderness and provider global assessment of disease activity. This result implies the importance of pain management in RA patients.
3.CT metal artifact correction using conditional diffusion model
Peiwen LIANG ; Mengxun ZHENG ; Long TANG ; Hua ZHANG
Chinese Journal of Medical Physics 2025;42(4):457-465
Objective To propose a conditional diffusion model based on template priors for correcting streaky metal artifacts characterized by alternating bright and dark patterns that appear in reconstructed computed tomography(CT)images due to the presence of metallic implants.Methods After isolating metal region using image segmentation technology to generate metal trajectory projection data,the projection data of metal trajectory and the corresponding projection data of template prior images were excluded.Subsequently,a conditional diffusion model was developed to recover the missing portions of the projection data in the metal-affected regions.Finally,the restored projection data were reconstructed using filtered back projection to obtain the corrected image.Results Compared with artifact disentanglement network and diffusion model,the proposed approach improved peak signal to noise ratio by 3.44 and 0.749 dB,and increased structural similarity index by 0.079 and 0.015,respectively.Conclusion The proposed approach outperforms traditional metal artifact correction methods and exhibits superior performance in reducing both streaky and shadow artifacts.
4.The characteristics and associated factors of hand dysfunction in patients with rheumatoid arthritis
Yaowei ZOU ; Ying YANG ; Zhiming OUYANG ; Jie PAN ; Peiwen JIA ; Kuimin YANG ; Huwei ZHENG ; Tao WU ; Jianzi LIN ; Jianda MA ; Yingqian MO ; Lie DAI
Chinese Journal of Internal Medicine 2025;64(2):119-127
Objective:To investigate the characteristics of hand dysfunction and its associated factors in patients with rheumatoid arthritis (RA).Methods:A cross-sectional study. Patients with RA were recruited from January 2019 to April 2024 at the Department of Rheumatology and Immunology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University. Demographic and clinical data were collected, including age, gender, active smoking, disease duration, time of morning stiffness, rheumatoid factor and anti-cyclic citrullinated peptide antibody, disease activity, radiographic indicators, and hand function assessment. Hand function was assessed by grip strength measures and self-reported items related to hand function in the Stanford Health Assessment Questionnaire. Factors related to hand function were analyzed by logistic regression analyses.Results:A total of 1 079 RA patients were recruited [mean age: (53.0±12.6) years]. Overall, 72.6% (783/1 079) patients experienced a decrease in grip strength, 57.2% (617/1 079) patients experienced a decreased grip strength in both hands, with the average grip strength of the left and right hands decreasing by 16.3% and 14.1%, respectively, compared to normal values; 39.9% (430/1 079) patients had self-reported hand dysfunction. There were 185 (17.1%) older RA patients (age ≥65 years). The proportion of older RA patients with decreased grip strength [89.7% (166/185) vs. 69.0% (617/894)] and degree of decrease in grip strength compared to normal values (left hand:-35.3%±30.6% vs. -12.3%±38.6%; right hand:-32.6%±32.3% vs. -10.3%±42.1%) were significantly higher than that in young patients, and the proportion of older patients with self-reported hand dysfunction was also significantly higher [53.0% (98/185) vs. 37.1% (332/894), all P<0.001]. Multivariate logistic regression analysis showed that pain visual analogue scale ( OR=1.375, 95% CI 1.020-1.854) was independently associated with grip strength decrease in older RA patients, while the 28-joint tender joint count ( OR=1.151, 95% CI 1.063-1.246) and provider global assessment of disease activity ( OR=1.381, 95% CI 1.171-1.628) were associated with self-reported hand dysfunction. Conclusions:Hand dysfunction is common in RA patients, especially among older RA patients, which is related to pain, joint tenderness and provider global assessment of disease activity. This result implies the importance of pain management in RA patients.
5.Time-series analysis of particulate matter and daily hospital visits for coronary heart disease in Yinzhou district, Ningbo area.
Zhenhua YE ; Peiwen ZHENG ; Peng SHEN ; Zhenyu ZHANG ; Huaichu LU ; Mingjuan JIN ; Hongbo LIN ; Jianbing WANG ; Kun CHEN ;
Journal of Zhejiang University. Medical sciences 2016;45(6):607-613
To explore the association between particulate matter (PM) and daily hospital visits of coronary heart diseases in Ningbo.Daily data of hospital visits from January 2014 to June 2015 (516 days in total) were obtained from the Yinzhou Health Information System in Ningbo. Daily air pollution data for PM and meteorological data were collected from the database of Ningbo Environmental Monitoring Center and Ningbo Meteorological Bureau. Time-series analysis by quasi-Poisson generalized additive model was used to examine the association between air pollution and hospital visits for coronary heart diseases by adjustment of long-term trends, seasonal patterns and meteorological variables (temperature, humidity), and day of week.An increase of an IQR of PMaccounted for 1.98% (95%:-0.59%-4.63%) increase of hospital visits for coronary heart diseases. The associations between PMand hospital visits for coronary heart diseases among female and the elderly (≥75 years) were stronger (=2.70%,95%:0.01%-5.47%;=3.35%, 95%0.12%-6.69%). The effects of PMattenuated after adjustment for PMPMhad short-term effects on daily hospital visits for coronary heart diseases in Ningbo, and such association was stronger among female and the elderly.
Age Factors
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Aged
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Air Pollutants
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adverse effects
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Air Pollution
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adverse effects
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statistics & numerical data
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China
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epidemiology
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Coronary Artery Disease
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epidemiology
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Female
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Hospitals
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utilization
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Humans
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Humidity
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adverse effects
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Male
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Middle Aged
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Particulate Matter
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adverse effects
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Seasons
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Sex Factors
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Temperature
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Time Factors

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