AIM: To investigate variation patterns of corneal biomechanical parameters and binocular symmetry among children of different genders aged 8-16 years.METHODS:A retrospective study was conducted, and children who underwent optometric examinations at the ophthalmology department of our hospital were enrolled between January 2022 and December 2024. Measurements included the flat keratometry(K1), steep keratometry(K2), and mean curvature(Km)of the anterior corneal surface, horizontal visible iris diameter(HVID), central corneal thickness(CCT), corneal endothelial cell density(CECD), average cell size(ACS), coefficient of variation(CV), and hexagonality(HEX). Corneal parameters and binocular differences were compared between genders and across age groups.RESULTS:A total of 621 children(1 242 eyes)were enrolled in this study, including 284 males(568 eyes), 337 females(674 eyes), 528 children aged 8-12 years(1 056 eyes), and 93 children aged 13-16 years(186 eyes). In children aged 8-16 years, the K1, K2, Km and CV of both eyes, as well as the interocular CCT differences in boys were significantly lower than those in girls(all P<0.05), while the HVID and HEX of both eyes, as well as the CCT of the left eye in boys were significantly higher than those in girls(all P<0.05). Children aged 8-12 years had significantly higher K1, Km, CECD and HEX in both eyes, and significantly lower ACS in both eyes than those aged 13-16 years(all P<0.05). K1, K2, Km, CECD and HEX in both eyes were negatively correlated with age(P<0.05); ACS in both eyes was positively correlated with age(P<0.001); K1 and Km of the right eye were positively correlated with the CECD of the right eye(P<0.05), and K1 and CCT of the left eye were positively correlated with the CECD of the left eye(P<0.05).CONCLUSION:Significant gender differences exist in corneal parameters among children aged 8 to 16 years, while binocular symmetry remained stable.

Objective:To screen the risk factors for non-complete procedural success of transvenous lead extraction(TLE),and to establish a prediction model based on the results and evaluate its predictive efficacy.Methods:A total of 1 029 patients who underwent TLE in Peking University People's Hospital from January 2014 to December 2020 were enrolled and divided into training set(n=720)and validation set(n=309)using the random number method.There were no statistically significant differences among the variables in the training set and the validation set.The training set was divided into the complete procedural success(CPS)group(n=664)and the non-CPS group(n=56).Univariate analysis was employed to screen the relevant indicators of non-CPS,followed by binary logistic regression analysis to identify the independent risk factors of non-CPS.Subsequently,a predictive model and nomogram were constructed.The receiver operating characteristic(ROC)curve analysis was applied to evaluate the ability of the model to distinguish non-CPS from TLE patients in the training set and validation set.The Hosmer-Lemeshow goodness-of-fit test was used to assess the consistency between the predicted risk and the actual risk of the model.Results:Univariate analysis showed that the relevant variables with P<0.1 including the age at the first implantation of the lead,the number of leads extracted,the oldest dwell time of lead extracted,the presence of abandoned leads,non-manual traction for lead extracted,the number of extracted leads>3,bilateral lead implantation,and the indications for TLE.The binary logistic regression analysis revealed that the presence of abandoned leads(OR=2.252,95%CI:1.111-4.564,P=0.024),the oldest dwell time of the extracted leads(OR=1.009,95%CI:1.005-1.012,P<0.001),and the number of extracted leads>3(OR=3.177,95%CI:1.306-7.733,P=0.011)were independent risk factors for non-CPS of TLE.ROC curve analysis revealed that the area under the ROC curve(AUC)of the training set was 0.80(95%CI:0.75-0.85,P<0.001).The AUC of the validation set was 0.81(95%CI:0.72-0.90,P<0.001).The Hosmer-Lemeshow goodness-of-fit test indicated that the P values of both the training set(P=0.089)and the validation set(P=0.136)were greater than 0.05.Conclusions:The presence of abandoned leads,the oldest dwell time of lead extracted,and the number of extracted leads>3 are independent risk factors for non-CPS in patients undergoing TLE.The nomogram model based on the above factors has satisfactory predictive ability.

Objective:To screen the risk factors for non-complete procedural success of transvenous lead extraction(TLE),and to establish a prediction model based on the results and evaluate its predictive efficacy.Methods:A total of 1 029 patients who underwent TLE in Peking University People's Hospital from January 2014 to December 2020 were enrolled and divided into training set(n=720)and validation set(n=309)using the random number method.There were no statistically significant differences among the variables in the training set and the validation set.The training set was divided into the complete procedural success(CPS)group(n=664)and the non-CPS group(n=56).Univariate analysis was employed to screen the relevant indicators of non-CPS,followed by binary logistic regression analysis to identify the independent risk factors of non-CPS.Subsequently,a predictive model and nomogram were constructed.The receiver operating characteristic(ROC)curve analysis was applied to evaluate the ability of the model to distinguish non-CPS from TLE patients in the training set and validation set.The Hosmer-Lemeshow goodness-of-fit test was used to assess the consistency between the predicted risk and the actual risk of the model.Results:Univariate analysis showed that the relevant variables with P<0.1 including the age at the first implantation of the lead,the number of leads extracted,the oldest dwell time of lead extracted,the presence of abandoned leads,non-manual traction for lead extracted,the number of extracted leads>3,bilateral lead implantation,and the indications for TLE.The binary logistic regression analysis revealed that the presence of abandoned leads(OR=2.252,95%CI:1.111-4.564,P=0.024),the oldest dwell time of the extracted leads(OR=1.009,95%CI:1.005-1.012,P<0.001),and the number of extracted leads>3(OR=3.177,95%CI:1.306-7.733,P=0.011)were independent risk factors for non-CPS of TLE.ROC curve analysis revealed that the area under the ROC curve(AUC)of the training set was 0.80(95%CI:0.75-0.85,P<0.001).The AUC of the validation set was 0.81(95%CI:0.72-0.90,P<0.001).The Hosmer-Lemeshow goodness-of-fit test indicated that the P values of both the training set(P=0.089)and the validation set(P=0.136)were greater than 0.05.Conclusions:The presence of abandoned leads,the oldest dwell time of lead extracted,and the number of extracted leads>3 are independent risk factors for non-CPS in patients undergoing TLE.The nomogram model based on the above factors has satisfactory predictive ability.

Objectives:To analyze the clinical characteristics,strategies,success and complication rates of lead extraction and re-implantation during the upgrade of cardiovascular implantable electronic devices(CIED)in non-infectious patients.Methods:This retrospective study collected and analyzed the baseline clinical data and surgical data of 66 non-infected patients who had their existing CIEDs(including cardiac pacemaker,implantable cardioverter defibrillator[ICD],cardiac resynchronization therapy pacemaker[CRT-P])upgraded to ICD or CRT-P or cardiac resynchronization therapy defibrillator(CRT-D)or subcutaneous implantable cardioverter defibrillator(S-ICD)in Peking University People's Hospital from March 2018 to March 2024.We analyzed the strategies of lead extraction and reimplantation as well as the operation success rate and complication rate.Results:Among the 66 patients,preoperative imaging revealed that 12 patients(18.2%)had severe stenosis/occlusion of the venous access route,with lead wear/perforation in 26 patients(39.4%).32 patients(48.5%)underwent transvenous lead extraction(TLE),of which all leads were removed in 27 patients(84.4%),and only non-functional leads were removed in 5 patients(15.6%).The success rate of the TLE procedure was 100%and no complication occurred.Among the 66 patients,functional leads retained and new leads were implanted on the same side in 28 patients(42.4%),all leads were removed and new leads were reimplanted on the opposite side in 22 patients(33.3%),only non-functional leads were removed and new leads were reimplanted on the same side in 5 patients(7.6%),all leads were removed and new leads were reimplanted on the same side in 5 patients(7.6%),and 6 patients(9.1%)had the leads abandoned and then were re-implanled.The success rate of the upgrade surgery was 100%,no complications were reported.Conclusions:When the existing CIEDs(including cardiac pacemaker,ICD,CRT-P)of non-infected patients are upgraded to ICD,CRT-P,CRT-D or S-ICD,lead extraction and reimplantation are safe and feasible,and reimplantation can be performed on the ipsilateral or contralateral side.

Alzheimer's disease(AD),a neurodegenerative disorder,manifests pathological changes in the brain even during the asymptomatic stage.As the pathological burden intensifies,patients experience functional decline in multiple cognitive domains,including memory,language,spatial perception,executive function,and calculation,and may also exhibit emotional abnormalities.Once AD progresses,treatment becomes extremely chal-lenging.Therefore,early diagnosis and accurate prediction of disease conversion are core tasks in the prevention and treatment of AD,and they are also urgent scientific research challenges to be overcome.Deep learning(DL)models demonstrate considerable advantages in the diagnosis,prediction,classification,and feature extraction of AD,offering new hope for solving this challenging problem.This research commences with a concise introduction to the outcomes of AD and the fundamental knowledge of deep learning.Subsequently,it offers an overview of the imaging studies on the utilization of deep learning for predicting disease transformation from two perspectives.Firstly,it systematically summarizes the existing DL models that have demonstrated innovation in the classification and prediction performance of AD.Secondly,it provides a comprehensive outline of the DL fusion models applied to the diagnosis,classification,and prediction of AD.Finally,this paper expounds upon the impending challenges in the research of this domain.This article demonstrates that deep learning models is cutting-edge trends in the ex-ploration of AD research.

Alzheimer disease(AD)is a neurological disease characterized by cognitive decline.AD continuum refers to the dynamic development progression from early pathological changes to obvious clinical symptoms,covering the continuous spectrum of subjective cognition decline(SCD)stage,mild cognitive impairment(MCI)stage and dementia stage.As one of the key brain regions involved in early stage,hippocampus(HP)in AD continuum is closely related to the progression of disease.MRI has been widely used in the study of HP in the AD continuum.The progresses in structural and functional MRI research of HP changes in AD continuum were reviewed in this article.

Objectives:To analyze the clinical characteristics,strategies,success and complication rates of lead extraction and re-implantation during the upgrade of cardiovascular implantable electronic devices(CIED)in non-infectious patients.Methods:This retrospective study collected and analyzed the baseline clinical data and surgical data of 66 non-infected patients who had their existing CIEDs(including cardiac pacemaker,implantable cardioverter defibrillator[ICD],cardiac resynchronization therapy pacemaker[CRT-P])upgraded to ICD or CRT-P or cardiac resynchronization therapy defibrillator(CRT-D)or subcutaneous implantable cardioverter defibrillator(S-ICD)in Peking University People's Hospital from March 2018 to March 2024.We analyzed the strategies of lead extraction and reimplantation as well as the operation success rate and complication rate.Results:Among the 66 patients,preoperative imaging revealed that 12 patients(18.2%)had severe stenosis/occlusion of the venous access route,with lead wear/perforation in 26 patients(39.4%).32 patients(48.5%)underwent transvenous lead extraction(TLE),of which all leads were removed in 27 patients(84.4%),and only non-functional leads were removed in 5 patients(15.6%).The success rate of the TLE procedure was 100%and no complication occurred.Among the 66 patients,functional leads retained and new leads were implanted on the same side in 28 patients(42.4%),all leads were removed and new leads were reimplanted on the opposite side in 22 patients(33.3%),only non-functional leads were removed and new leads were reimplanted on the same side in 5 patients(7.6%),all leads were removed and new leads were reimplanted on the same side in 5 patients(7.6%),and 6 patients(9.1%)had the leads abandoned and then were re-implanled.The success rate of the upgrade surgery was 100%,no complications were reported.Conclusions:When the existing CIEDs(including cardiac pacemaker,ICD,CRT-P)of non-infected patients are upgraded to ICD,CRT-P,CRT-D or S-ICD,lead extraction and reimplantation are safe and feasible,and reimplantation can be performed on the ipsilateral or contralateral side.

Objectives:To evaluate the performance of AVEIR VR single chamber leadless pacemaker(AVEIR VR)in the real world in China and the predictive factors of pacing threshold to assess the feasibility of AVEIRTM VR implantation in the domestic population.Methods:All patients who underwent AVEIR VR implantation by experienced operators from Peking University People's Hospital in multiple domestic hospitals from June 2024 to October 2024 were consecutively included,and their baseline characteristics,procedural data(including pacemaker electrical measurements at various stages),and follow-up results were observed,recorded,and statistically analyzed.Results:This study included 20 patients who met the indication for pacemaker implantation and underwent AVEIR VR implantation.Their mean age was(71.40±13.37)years,body mass index(BMI)was(23.05±3.71)kg/m2,body surface area(BSA)was(1.70±0.16)m2,all 20 patients were successfully implanted with pacemakers,there were no major complications(newly occurred pericardial effusion during the perioperative period,cardiac tamponade,poor pacemaker function,pacemaker dislocation/perforation,tricuspid valve injury,myocardial infarction,stroke,pulmonary embolism,and clinical death).One patient developed new frequent ventricular premature contractions after pacemaker release.The pacing threshold(PCT)at one week after implantation was correlated with PCT in tether mode(r=0.650,P=0.009)and PCT in release phase(r=0.596,P=0.019),but not with the sensing and impedance in each phase.Conclusions:This preliminary exploration study show that AVEIRTM VR implantation demonstrates satisfactory performance among real world patients in China,especially in elderly and low weight populations,confirming its safety.

OBJECTIVE: To explore the effectiveness of free paraumbilical perforator flaps in repairing skin and soft tissue defects in children. METHODS: Between February 2018 and March 2024, 12 children with skin and soft tissue defects were treated with the free paraumbilical perforator flaps. There were 7 boys and 5 girls with an average age of 6.3 years (range, 2-12 years). The defects located on the upper limbs in 6 cases, lower limbs in 5 cases, and neck in 1 case. The causes of wounds included 7 cases of electrical burns, 1 case of thermal burn, 2 cases of scar release and excision due to scar contraction after burns, 1 case of scar ulcer at the amputation stump after severe burns, and 1 case of skin necrosis after a traffic accident injury. The size of defects after debridement ranged from 7.0 cm×4.0 cm to 18.0 cm×10.0 cm. According to the defect size, 11 cases were repaired with unilateral paraumbilical perforator flaps centered on the umbilicus, among which 3 cases with larger defects were designed as "L"-shaped flaps along the lateral and lower ends of the perforator; the donor sites were directly closed. One case with extensive defect after scar excision and release was repaired with bilateral expanded paraumbilical perforator flaps; the donor sites were repaired with autologous split-thickness skin grafts. The size of flaps ranged from 9.0 cm×4.0 cm to 20.0 cm×11.0 cm. Postoperatively, analgesia and sedation were provided, and the blood supply of the flaps was observed. RESULTS: All operations were successfully completed. The operation time was 4-7 hours, with an average of 5.0 hours. After postoperative analgesia and sedation, the visual analogue scale (VAS) score for pain in all children was less than or equal to 3, and there was no non-cooperation due to pain. All flaps and skin grafts survived completely, and the wounds healed by first intention. Ten children underwent 1-4 times of flap de-fatting, finger separation, and trimming. All children were followed up 6-48 months (mean, 26.6 months). No obvious swelling of the flaps occurred, and the texture was soft. At last follow-up, among the 6 children with upper limb defects, 2 had upper limb function grade Ⅳ and 4 had upper limb function grade Ⅴ according to the Carroll upper limb function assessment method. The 4 children with lower limb defects had no limitation of joint movement. The neck flexion and rotation in the 1 child with neck defect significantly improved when compared with that before operation. The 1 child with residual ulcer at the amputation stump could wear a prosthesis and move without limitation, and no new ulcer occurred. Linear scars were left at the donor sites, and no abdominal wall hernia was formed. CONCLUSION The free paraumbilical perforator flap has abundant blood supply and can be harvested in large size. It can be used to repair skin and soft tissue defects in children and has the advantages of short operation time, minimal injury, high safety, and minimal impact on the growth and development of children.
Humans ; Perforator Flap/transplantation* ; Child ; Male ; Female ; Soft Tissue Injuries/surgery* ; Child, Preschool ; Plastic Surgery Procedures/methods* ; Burns/surgery* ; Umbilicus/surgery* ; Skin Transplantation/methods* ; Skin/injuries* ; Cicatrix/surgery* ; Treatment Outcome

Objective To initially explore the possibility of applying the fluorescence micro-optical sectioning tomography(fMOST)high-resolution 3D reconstruction system to the morphological study of the intestinal nervous system and to preliminarily establish a method for studying the morphology of the intestinal nervous system using this system.Methods fMOST high-resolution 3D reconstruction system was used to study the intestinal nervous system of C57BL/6 mice in detail.Based on this method,a new morphological method of the visceral nervous system of small animal models was explored at the single-cell level.Results Compared with the large intestine,the small intestine lacked the typical myenteric plexus(Auerbach),deep mucosal plexus(Henley),and submucosal superficial plexus(Meissner).Conclusion The result of this paper provide a clearer and systematic display of the anatomical structure of the enteric nervous system in C57BL/6 mice,and further clarify the similarities and differences between the enteric nervous system of mice and human,and provide a theoretical basis for its rational application in the study of digestive system diseases.The morphological study of fMOST high-resolution 3D reconstruction system is not limited to the central nervous system,but can be extended to the morphological study of multiple visceral nervous systems.