Registration of serial images plays an increasingly important role in medicine. A novel registration method used for serial images matching is proposed, which is based on the joint histogram. After thresholding the two images to be registered, the joint histogram is divided into four separate regions. Then the criterion function is defined as bin counting in a specific region of the joint histogram, which simplifies the computation of the criteria function greatly and speeds up the alignment process significantly. We choose the Powell optimization algorithm to calculate the registration parameters. The comparison of the results from both mutual information and our method shows that the new method based on segmentation and counting is a fast, simple, efficient and accurate registration method.

Objective To analyze the curative effect of minimally invasive incision combined with plate fixation for calcaneal fractures.Methods Retrospectively analyzed the clinical data of 30 cases(30 feet) of calcaneal fractures who were treated with minimal incision(sinus tarsi approach combined with posterior lateral incision) from August 2014 to August 2015.Minimally invasive incision combined with plate fixation were performed for the treatment.X-rays were taken in the regular follow-up,B(o)hler and Gissane angle as well as the complications were measured.The final curative effect was comprehensively assessed according to the ankle hind foot score of American Aryhopaedic Foot and Ankle Society(AOFAS).Results All cases were followed up for an average of 14.5 months (from 12 to 16 months), and all fractures healed with no complication such as incision infection or poor healing.The average B(o)hler angle was improved from preoperative(13.42°±4.2°) to (29.3°±3.8°) at the last follow-up with a significant difference(t=-20.424,P=0.000),and the average Gissane angle was significantly improved from preoperative(97.8°±9.7°) to (123.6°±6.5°) at the last follow-up (t=-17.5,P=0.000).The outcomes were evaluated with AOFAS,resulting in an excellent and good rate of 83.3%.Conclusion Treatment of calcaneal fractures with minimal incision has the advantages of less trauma,lower incision complication rate,stronger reduction and fixation,which can achieve satisfactory outcomes.

BACKGROUNDTo establish a cohort for the study of risk factors of lung cancer, and to support the study of early biomarkers and prevention of lung cancer.

METHODSDesigned a special population-based prospectively dynamic cohort among radon- and arsenic-exposed tin miners aged 40 or more years old with at least 10 years of occupational exposure in Yunnan Province, P.R.China. The mass screenings with sputum cytology and chest X-ray were conducted annually. The baseline information was collected for assessing demographic characteristics and risk factors. The multiple sputum specimens, chest radiographs and numerous biologic specimens have been collected and stored.

RESULTSFrom 1992-1999, 9143 miners have been enrolled and 460 new cases of lung cancer have been found. There had 47655 person-time chest radiographs and 46625 person-time sputum cytology among the cohort in 8 years. The relative risks of age-adjusted exposure to chronic bronchitis, silicosis, and tobacco were 1.73, 1.46, and 1.32 respectively.

CONCLUSIONSA cohort of unique occupationally-exposed tin miners with an extensive biologic specimen repository and data bank has been successfully established. Although occupational exposures are the predominant risk factors among the high risk miners, lung cancer risk is also associated with chronic obstructive lung disease (chronic bronchitis and silicosis) and a number of measures of exposure to tobacco smoke, including early age of first use, duration, and cumulative exposure.

BACKGROUNDLung cancer has become the leading cause of the cancer death in China. Population-based lung cancer screening is still in controversy. The objective of this study is to analyze the effect of annual chest radiography and sputum cytological screening conducted in high lung cancer risk population who were exposed to work related carcinogens.

METHODSA retrospective analysis was conducted to evaluate the screening results of the lung cancer cases diagnosed from 1992 to 2001 in the miners of Yunnan tin mine.

RESULTSA total of 9317 miners had been screened annually from 1992 to 1999. A total of 46 779 chest radiography and 45 672 sputum cytological examinations had been conducted, and 793 cohort subjects had at least one positive result. The annual positive detection rate ranged from 1214.1/100 000 to 3482.7/100 000. By December 31, 2001, 433 lung cancer cases had been confirmed, 371 cases out of them had cytological/pathological evidence, and 55.0% were squamous cell carcinoma followed by adenocarcinoma and small cell carcinoma. Stage I or II accounted for 24%. 62.1% of the cases had at least one positive screening result, while 165 cases were detected by chest radiography alone, 56 were detected by sputum cytology, and 48 were detected by both screening modalities. 64.2% of X-ray detected cases were squamous/adenous carcinomas and 75.0% of cytological detected cases were squamous carcinoma. 80.8% of early stage cases had at least one previous positive finding from screening.

CONCLUSIONSAnnual lung cancer screening with combination of chest radiography and sputum cytology play some extent role in early detection of lung cancer in high risk population. The results may provide some primary data for lung cancer screening in special population who are at high risk of lung cancer in China.

It is an important morphological research method to reconstruct the 3D imaging from serial section tissue images. Registration of serial images is a key step to 3D reconstruction. Firstly, an introduction to the segmentation-counting registration algorithm is presented, which is based on the joint histogram. After thresholding of the two images to be registered, the criterion function is defined as counting in a specific region of the joint histogram, which greatly speeds up the alignment process. Then, the method is used to conduct the serial tissue image matching task, and lies a solid foundation for 3D rendering. Finally, preliminary surface rendering results are presented.
Algorithms ; Image Processing, Computer-Assisted ; methods ; Imaging, Three-Dimensional ; Microtomy ; methods

Objective To investigate the impact of the interaction of fasting blood glucose(FBG)and serum uric acid(SUA)on diabetic retinopathy(DR).Methods A total of 306 diabetes mellitus(DM)patients diagnosed and re-ceived comprehensive ophthalmic examination in the First Affiliated Hospital of Gannan Medical University from January 2019 to January 2021 were selected.According to the presence or absence of DR,these patients were divided into the DR group(178 patients)and the non-DR(NDR)group(128 patients).The general clinical data of patients in the two groups were compared.The least absolute shrinkage and selection operator(LASSO)regression method and multivariate Logistic regression analysis were used to screen the independent influencing factors of DR in DM patients,and the odds ratio of risk factors was calculated.The sensitivity analysis of the results was performed using the E-value method.The interaction of FBG and SUA on DR in DM patients was analyzed by an additive interaction model.The Nomogram model to predict DR in DM patients was constructed and verified internally.The receiver operating characteristic curve(ROC)was used to evalu-ate the effects of FBG,SUA and both FBG and SUA on DR in DM patients.Results Compared with the NDR group,the course of DM in the DR group was significantly longer,the proportion of patients with history of oral medication was signif-icantly lower,the proportion of patients with history of insulin therapy was significantly higher,and the levels of total cho-lesterol,triglyceride,low-density lipoprotein cholesterol,high-density lipoprotein cholesterol,blood urea nitrogen,serum creatinine,SUA and FBG were significantly higher(all P＜0.05).The history of insulin therapy,course of DM≥9.66 years,TG≥2.07 mmol·L-1,SUA ≥ 297.73 μmol·L-1 and FBG ≥8.92 mmol·L-1 were the risk factors for DR in DM pa-tients,while the history of oral medication was the protective factor for DR in DM patients.The Nomogram model based on the above independent risk factors was accurate in predicting the occurrence of DR in DM patients.SUA and FBG had inter-active effects on DR in DM patients.The value of SUA-FBG interaction in the diagnosis of DR was greater than that of both alone.Conclusion SUA≥ 297.73 μmol·L-1 and FBG ≥8.92 mmol·L-1 are the risk factors for DR in DM patients.The value of interaction of FBG and SUA in the diagnosis of DM accompanied by DR is greater than that of both alone.

Objective　To study the occupational lung cancer among Yunnan tin miners during 1992-1997 by sputum cytology. Methods　The data of cases and occupational high-risk population for lung cancer among tin miners (Age≥40 years old and worked underground and／or at smeltery≥10 years) were analyzed. Results　There were 339 patients with lung cancer determined during six years, in which squamous cell carcinoma was 56.34％. The average incidence age was 65.78 years of age. The average positive rate to sputum cytology examination was 32.74％. The accuracy, specificity and sensitivity to sputum cytology examination were 99.35％, 99.81％ and 39.22％ respectively. The positive predictive value of sputum cytology examination was 62.01％, which was significantly higher than X-ray (33.05％)(P＜0.01). There were 48 recessive lung cancer cases and 12 suspicious recessive lung cancer cases found with sputum cytology during the six years. Conclusion　The sputum cytology examination is still one of the most effective methods for lung cancer screening among occupational high-risk population. The occupational high-risk population should be defined again (the tin miners' age≥50 years old and had worked underground and／or at smeltery≥10 years).

Objective:To evaluate the effect of virtual reality arthroscopic simulation system combined with case-based learning (CBL) in orthopedic clinical teaching.Methods:From January 2021 to June 2022, a total of 36 residents who took the standardized residency training at Department of Articular Orthopedics in The Third Affiliated Hospital of Soochow University were enrolled in this study. They were randomized into an experimental group and a control group, with 18 trainees in each group. The experimental group adopted the virtual reality arthroscopic simulation system combined with CBL teaching mode, while the control group adopted simple endoscopic simulation training box with traditional teaching mode. Theoretical and practical tests and questionnaire survey were carried out to evaluate the teaching effects in two groups. SPSS 22.0 was performed to conduct t-test on the measurement data between the two groups. Results:The theoretical and practical test scores of the experimental group [(89.39±3.09) and (82.72±4.28)] were better than those of the control group [(86.22±4.43) and (76.61±5.65)], with statistically significant differences ( t= 2.49, P=0.018; t=3.66, P=0.001). The questionnaire survey showed that the experimental group was better than the control group in creating novel forms of courses [(4.94±0.24) vs. (4.11±0.58), t=5.62, P<0.001], simulating more real scenes [(4.83±0.38) vs. (3.78±0.43), t=7.80, P<0.001], inspiring learning interests [(4.78±0.43) vs. (4.00±0.59), t=4.51, P<0.001], improving practical skills [(4.83±0.38) vs. (3.83±0.51), t=6.61, P<0.001], and building career confidence [(4.50±0.62) vs. (3.06±0.54), t=7.47, P<0.001], with statistically significant differences (all P<0.001). Conclusions:The virtual reality arthroscopic simulation system combined with CBL teaching mode can better simulate the real clinical scenes, help inspire the interest of learning and quickly improve practical skills, thereby improving the effect of orthopedic clinical teaching.

Objective:To investigate the prognostic value of serum adenosylhomocysteinase (AHCY) in patients with hepatitis E virus acute liver failure (HEV-ALF).Methods:From 1 January 2017 to 31 December 2022, 100 patients each with HEV-ALF and acute hepatitis E (AHE) from the First Affiliated Hospital of Medical School of Zhejiang University and Affiliated Suzhou Hospital of Nanjing Medical University were included in this case-control study. The HEV-ALF group was 58.56±11.16 years old, including 71 men. The AHE group was 56.04±14.30 years old, including 61 men. All serum samples were obtained before the patient had an acute onset and were obtained without treatment. Firstly, the serum AHCY levels in patients with HEV-ALF and AHE were analyzed by ELISA. Secondly, the serum AHCY levels in HEV-ALF patients with different organ failure and disease condition were compared. According to the number of organ failure, 100 HEV-ALF patients were divided into organ failure number=2 group ( n=58), number=3 group ( n=24) and number>3 groups ( n=18). According to the disease condition, 100 patients were divided into improvement group ( n=49), disease fluctuation group ( n=37), and deterioration group ( n=14). Thirdly, the survival times between the high serum AHCY level group ( n=50) and the low serum AHCY level group ( n=50) were compared. Finally, the independent risk factors to predict mortality using the multivariate Logistic regression analysis, and evaluated the predictive and decision-making abilities of serum AHCY levels were explored using the receiver operating characteristic (ROC) curve and decision curve analysis (DCA). Results:Serum AHCY levels in HEV-ALF patients were significantly higher than those in AHE patients [326.92 (295.37-385.84) pg/ml vs. 222.88 (188.04-246.78) pg/ml, Z=-12.217, P<0.001]. Serum AHCY levels in group 2 were significantly lower than those in group 3 [303.44 (284.40-330.15) pg/ml vs. 335.36 (306.30-385.84) pg/ml, Z=-3.353, P=0.001]. Serum AHCY level in group 3 were significantly lowerthan those in group>3 [335.36 (306.30-385.84) pg/ml vs. 549.89 (423.35-660.22) pg/ml, P<0.001]. The serum AHCY levels in the fluctuation group were lower than those in the deterioration group [322.17 (283.92-423.74) pg/ml vs. 458.26 (374.66, 593.89) pg/ml, Z=-4.016, P=0.009]. The survival time of high serum AHCY level group was significantly lower than that of low serum AHCY level group [23.11 (20.25-25.96) days vs. 29.49 (28.79-30.20) days, Z=-2.596, P<0.001]. The multivariate Logistic regression analysis showed that the levels of serum AHCY and total bilirubin were independent risk factors to predict mortality in HEV-ALF patients [AHCY, OR (95% CI): 1.008 (1.002-1.015), P=0.008; total bilirubin, OR (95% CI): 1.011 (1.005-1.018), P=0.001]. Serum AHCY level predicting the area under the curve (AUC) of 30-day mortality in HEV-ALF patients was 0.912, with a sensitivity of 90.00% and a specificity of 93.75%. DCA results demonstrated that serum AHCY level had good decision-making power for predicting 30-day mortality in HEV-ALF patients. Conclusion:Serum AHCY has an important prognostic value for HEV-ALF patients. Higher serum AHCY levels indicate the worse prognosis of HEV-ALF patients.