Objective:To analyze and compare the interfractional setup errors between two body posi-tioning fixation methods(lithotomy position with carbon fiber full-body fixation frame vs.conventional carbon fiber body fixation frame combined with thermoplastic membrane)in radical radiotherapy for pros-tate cancer,and to calculate the clinical target volume(CTV)to planning target volume(PTV)margin(MPTV)for both methods to optimize immobilization techniques and radiotherapy workflows.Methods:A retrospective analysis was conducted on 37 consecutive patients who underwent radical prostate radio-therapy at Peking University First Hospital between August 2021 and March 2023.The patients were di-vided into two groups based on the immobilization method:Group A(18 patients,450 CBCT image sets)used a carbon fiber whole-body fixator in the lithotomy position,while Group B(19 patients,461 CBCT image sets)used a conventional carbon fiber fixator combined with a thermoplastic mask.All the patients underwent daily cone-beam computed tomography(CBCT)image guidance.Bone registration combined with manual registration was used to obtain the setup error data in the left-right(X),cranio-caudal(Y)and anterior-posterior(Z)directions.The positioning errors of the two groups were compared by using the independent sample t-test,the Mann-Whitney U test and the chi-square test.The average positioning error,systematic positioning error(Σ)and random positioning error(δ)were calculated,and the CTV-PTV extension distance was calculated by using the(MPTV=2.5Σ+0.7δ).Results:The analysis of the setup errors in the three-dimensional direction showed significant differences between the two groups(all P＜0.01).Specifically,the median(quartile)absolute values of the errors in the X,Y,and Z di-rections of group A were[0.40(0.20,0.70)cm,0.50(0.30,0.80)cm,and 0.35(0.20,0.60)cm],respectively.In group B,the corresponding values were significantly reduced to[0.20(0.10,0.40)cm,0.40(0.20,0.70)cm and 0.20(0.10,0.40)cm].The results of Mann-Whitney U test showed that the differences in each direction were highly statistically significant(X:z=-6.86;Y:z=-2.76;Z:z=-5.71).The cumulative distribution ratio of the setup error displacement within 0.5 cm in the X,Y,and Z directions in group A and group B were 297(66.0％)and 408(88.5％)(P＜0.01),250(55.6％)and 285(61.8％)(P=0.055),308(68.4％)and 391(84.8％)(P＜0.01),re-spectively.The CTV-PTV margins in three directions were X 0.66 cm in group A and 0.35 cm in group B;Y0.67 cm and 0.45 cm;Z 0.54 cm and 0.42 cm.Conclusion:Conventional carbon fiber human body fixator combined with thermoplastic film can significantly reduce the setup error.However,the car-bon fiber whole-body fixator in the lithotomy position demonstrated larger setup errors in the X,Y,and Z directions compared with the conventional fixator combined with a thermoplastic mask,indicating the need for further workflow optimization.Given that the lithotomy position is essential for transperineal ultrasound-guided techniques,further research and improvements are required to achieve higher positioning accuracy.

Objective:To investigate the clinical characteristics of patients with high-myopia macular hole retinal detachment (MHRD) combined with choroidal detachment and to preliminarily analyze factors associated with postoperative hole closure.Methods:A retrospective clinical case series study. A total of 68 patients with high myopia (68 eyes) with MHRD diagnosed by Department of Ophthalmology, Peking University People’s Hospital from January 2019 to April 2024 were included in this study. Among them, there were 14 males (14 eyes) and 54 females (54 eyes). The mean age was (61.10±9.66) years. All eyes were treated with pars plana vitrectomy (PPV) combined with silicone oil or gas filling. Best corrected visual acuity (BCVA), intraocular pressure, and B-mode ultrasonography were performed. The BCVA test was performed using the Snellen visual acuity chart, which was statistically converted to logarithm of the minimum angle of resolution (logMAR) visual acuity. The range of choroidal detachment was defined according to the number of involved quadrants observed in B-mode ultrasound or surgery, which was divided into 1 to 4 quadrants. Axial length (AL) was measured under retinal reattachment. In 68 eyes, there were 17 eyes with choroidal detachment and 51 eyes without choroidal detachment, respectively. There were 17 eyes with choroidal detachment, and the detachment range involved 1, 2, 2 and 12 eyes in 1, 2, 3 and 4 quadrants, respectively. During operation, 13% C 3F 8 was filled in 2 eyes, all of which were not complicated with choroidal detachment. 66 eyes were filled with silicone oil. According to whether the patients were complicated with choroidal detachment, the patients were divided into the group without choroidal detachment and the group with choroidal detachment. Independent sample t test, Welch two-sample t test or Mann-Whitney U test were used for comparison between groups. Generalized linear regression and logistic regression were used to analyze the relationship between the aperture size of postoperative unclosed holes and the closed hole after surgery and clinical factors. Results:At 3 months after surgery, the logMAR BCVA of the affected eye was 1.29±0.43, with a preoperative to postoperative difference ranging from -1.60 to 0.70 (-0.51±0.51) logMAR units. The AL ranged from 26.6 to 34.3 (29.60±2.12) mm. Among 68 eyes, macular hole of 37 (54.4%, 37/68) eyes were open and 31 (45.6%, 31/68) eyes were closed, respectively. The hole diameter of the open eye was (753±424) μm. There was no significant difference in age, course of disease and AL between the two groups ( W=412.0, 477.5, 427.0; P>0.05). Before operation, BCVA in patients with choroidal detachment was worse ( W=257.5) and intraocular pressure was lower ( t=4.051) in patients with choroidal detachment compared with those without choroidal detachment, with statistical significance ( P<0.05). At 3 months after surgery, BCVA in patients with choroidal detachment was significantly worse than that in patients without choroidal detachment, with statistical significance ( W=284.0, P<0.05). There were no significant differences in logMAR BCVA difference ( t=0.616) and macular hole closure rate ( χ 2=0.000) before and after surgery ( P>0.05). The reoperation rate of retinal detachment due to persistent or recurrent retinal detachment was significantly higher in the group with choroid detachment than in the group without choroid detachment, and the difference was statistically significant (odds ratio=6.424, P<0.05). Logistic regression analysis showed that young age was significantly correlated with macular hole closure failure after surgery ( β=0.077, P=0.015). There was no correlation between AL, duration of disease, BCVA before surgery, intraocular pressure, wether combined with choroid detachment range and postoperative hole closure ( β=-0.072, 0.000, 0.672, -0.085, -0.391; P>0.05). Conclusions:Concomitant choroidal detachment adversely affected on both pre-operative and post-operative visual acuity in high myopia MHRD. It is closely associated with the risk of recurrent retinal detachment and the needs of multiple operations, but has no significant effect on hole closure rate. Lower age of onset may be a risk factor for macular hole closure.

Objective:To observe and analyze the correlation between ectopic foveal inner layer (EIFL) and the EIFL-based idiopathic epiretinal membrane (ERM) staging system and the anatomic and functional prognosis of ERM eyes post pars plana vitrectomy (PPV).Methods:A retrospective study. From January 1, 2020 to October 30, 2023, 345 eyes of 330 patients diagnosed with idiopathic ERM in Department of Ophthalmology of Peking University People's Hospital and treated with standard transciliary flat three-channel 25G PPV combined with ERM and internal limiting membrane exfoliation were included in the study. Among them, 96 were males (111 eyes) and 234 were females (234 eyes). The mean age was (66.8±7.7) years. All study eyes received standard three-port 25G PPV combined with ERM and internal limiting membrane peeling. All study eyes underwent best corrected visual acuity (BCVA) and optical coherence tomography (OCT) examinations. BCVA was performed using a standard logarithmic visual acuity chart and converted to logarithm of the minimum angle of resolution visual acuity for statistical analysis. EIFL thickness and central foveal thickness (CFT) on OCT were measured. ERM eyes were grouped into stage Ⅰ, Ⅱ, Ⅲ and Ⅳ according to ERM staging scheme based on EIFL; disorganization of the retinal inner layers (DRIL) of study eyes were assessed and grouped into no, mild and severe groups. The correlation between ERM staging as well as EIFL thickness and the anatomical and functional prognosis 6 months post-PPV were analyzed.Results:Among 345 study eyes, 12, 87, 174 and 72 eyes were stage Ⅰ-Ⅳ ERM respectively, 63 with no DRIL, 216 with mild DRIL and 66 with severe DRIL. Among the 153 eyes with macular edema, the edema subsided in 66 eyes (43.1%, 66/153) 6 months after the operation. Eighty-seven eyes (56.9%, 87/153) did not regress. The edema subsided 6 months after the operation was not significantly correlated with the ERM stage before the operation ( χ2=3.331, R=?0.145, P=0.304) or the degree of DRIL ( χ2=0.655, R=?0.108, P=0.445). The results of the correlation analysis showed that logMAR BCVA 6 months after the surgery was positively correlated with the degree of DRIL before the surgery ( Tau-b=0.236), ERM stage ( Tau-b=0.194), CFT ( r=0.383), and EIFL thickness ( r=0.317) ( P<0.05). There was no significant correlation with the thickness of the outer nuclear layer before the operation ( r=0.004, P>0.05). Preoperative ERM stage ( Tau-b=0.303, P<0.001) and DRIL severity ( Tau-b= 0.238, P=0.001) were positively correlated with CFT at 6 months after surgery. Conclusion:The ERM stage and EIFL thickness before the operation are positively correlated with logMAR BCVA and CFT 6 months after the operation.

Objective To observe the clinical effect of Huangqi Yixin Decoction combined with sacubitril/valsartan in treatment of patients with heart failure with preserved ejection fraction(HFpEF)of Qi deficiency and blood stasis type.Methods A total of 86 patients with HFpEF of Qi deficiency and blood stasis type were randomly divided into western medicine group and combination group using the random number table method,with 43 cases in each group.The western medicine group was trea-ted with sacubitril/valsartan sodium tablets on the basis of conventional anti-heart failure therapy,while the combination group was additionally treated with Huangqi Yixin Decoction on the basis of the western medicine group's treatment.The therapeutic efficacy,traditional Chinese medicine(TCM)syndrome scores,cardiac function indicators[Tei index,N-terminal pro-brain natriuretic peptide(NT-proBNP)],exercise tolerance[6-minute walk distance(6MWD),maximum exercise heart rate,metabolic equivalent(MET)],and the occurrence of adverse reactions were compared between the two groups.Results The overall clinical effective rate in the combination group was 93.02％,which was higher than that in the western medicine group(76.74％),and the difference was statistically significant(P＜0.05).After treatment,the TCM syndrome scores in both groups were lower than those before treatment,and the scores in the combination group were lower than those in the western medicine group,with a statistically significant difference(P＜0.05).After treatment,the levels of Tei index and NT-proBNP in both groups were lower than those before treatment,and the levels in the combination group were lower than those in the western medicine group,with a statistically sig-nificant difference(P＜0.05).After treatment,the 6MWD,maximum exercise heart rate,and MET in both groups were higher than those before treatment,and the values in the combination group were higher than those in the western medicine group,with a statistically significant difference(P＜0.05).The incidence of adverse reactions in the western medicine group was 18.60％,which was higher than that in the combination group(4.65％),and the difference was statistically signifi-cant(P＜0.05).Conclusion Huangqi Yixin Decoction combined with sacubitril/valsartan has a good therapeutic effect on HFpEF of Qi deficiency and blood stasis type.It can reduce the TCM syn-drome scores of patients,improve exercise tolerance,and has good safety.

Objective To use a physics-informed neural network(PINN)-based model to predict hemodynamics in intracranial aneurysms and address the problems of long simulation time and high computational cost in traditional computational fluid dynamics(CFD)simulations.Methods The PINN model was trained using only the computational domain coordinates and sparse velocity measurement points from CFD data of clinical patients.The predicted blood flow velocity,pressure,and wall shear stress(WSS)from the PINN model were compared with CFD simulation results.Results The proposed method was used to test and validate data from four different patients.For velocity prediction,the average mean absolute error(MAE),average mean relative error(MRE),average mean squared error(MSE)was 4.60％,6.61％,and 0.229％,respectively.For WSS prediction,the average MAE,MRE and MSE was 5.54％,8.58％,and 0.510％,respectively.The PINN model demonstrated a good generalization capability across different aneurysm models and could reduce the computation time of hemodynamics from several hours to just a few seconds.Conclusions The PINN model can effectively compensate for incomplete measurement data through physical constraints,even when boundary conditions are unknown and measurement data are sparse.It can rapidly and accurately simulate the hemodynamics of intracranial aneurysms.This method has the potential to provide effective support for clinical risk prediction in intracranial aneurysms.

Objective:To analyze and compare the interfractional setup errors between two body posi-tioning fixation methods(lithotomy position with carbon fiber full-body fixation frame vs.conventional carbon fiber body fixation frame combined with thermoplastic membrane)in radical radiotherapy for pros-tate cancer,and to calculate the clinical target volume(CTV)to planning target volume(PTV)margin(MPTV)for both methods to optimize immobilization techniques and radiotherapy workflows.Methods:A retrospective analysis was conducted on 37 consecutive patients who underwent radical prostate radio-therapy at Peking University First Hospital between August 2021 and March 2023.The patients were di-vided into two groups based on the immobilization method:Group A(18 patients,450 CBCT image sets)used a carbon fiber whole-body fixator in the lithotomy position,while Group B(19 patients,461 CBCT image sets)used a conventional carbon fiber fixator combined with a thermoplastic mask.All the patients underwent daily cone-beam computed tomography(CBCT)image guidance.Bone registration combined with manual registration was used to obtain the setup error data in the left-right(X),cranio-caudal(Y)and anterior-posterior(Z)directions.The positioning errors of the two groups were compared by using the independent sample t-test,the Mann-Whitney U test and the chi-square test.The average positioning error,systematic positioning error(Σ)and random positioning error(δ)were calculated,and the CTV-PTV extension distance was calculated by using the(MPTV=2.5Σ+0.7δ).Results:The analysis of the setup errors in the three-dimensional direction showed significant differences between the two groups(all P＜0.01).Specifically,the median(quartile)absolute values of the errors in the X,Y,and Z di-rections of group A were[0.40(0.20,0.70)cm,0.50(0.30,0.80)cm,and 0.35(0.20,0.60)cm],respectively.In group B,the corresponding values were significantly reduced to[0.20(0.10,0.40)cm,0.40(0.20,0.70)cm and 0.20(0.10,0.40)cm].The results of Mann-Whitney U test showed that the differences in each direction were highly statistically significant(X:z=-6.86;Y:z=-2.76;Z:z=-5.71).The cumulative distribution ratio of the setup error displacement within 0.5 cm in the X,Y,and Z directions in group A and group B were 297(66.0％)and 408(88.5％)(P＜0.01),250(55.6％)and 285(61.8％)(P=0.055),308(68.4％)and 391(84.8％)(P＜0.01),re-spectively.The CTV-PTV margins in three directions were X 0.66 cm in group A and 0.35 cm in group B;Y0.67 cm and 0.45 cm;Z 0.54 cm and 0.42 cm.Conclusion:Conventional carbon fiber human body fixator combined with thermoplastic film can significantly reduce the setup error.However,the car-bon fiber whole-body fixator in the lithotomy position demonstrated larger setup errors in the X,Y,and Z directions compared with the conventional fixator combined with a thermoplastic mask,indicating the need for further workflow optimization.Given that the lithotomy position is essential for transperineal ultrasound-guided techniques,further research and improvements are required to achieve higher positioning accuracy.

Objective To use a physics-informed neural network(PINN)-based model to predict hemodynamics in intracranial aneurysms and address the problems of long simulation time and high computational cost in traditional computational fluid dynamics(CFD)simulations.Methods The PINN model was trained using only the computational domain coordinates and sparse velocity measurement points from CFD data of clinical patients.The predicted blood flow velocity,pressure,and wall shear stress(WSS)from the PINN model were compared with CFD simulation results.Results The proposed method was used to test and validate data from four different patients.For velocity prediction,the average mean absolute error(MAE),average mean relative error(MRE),average mean squared error(MSE)was 4.60％,6.61％,and 0.229％,respectively.For WSS prediction,the average MAE,MRE and MSE was 5.54％,8.58％,and 0.510％,respectively.The PINN model demonstrated a good generalization capability across different aneurysm models and could reduce the computation time of hemodynamics from several hours to just a few seconds.Conclusions The PINN model can effectively compensate for incomplete measurement data through physical constraints,even when boundary conditions are unknown and measurement data are sparse.It can rapidly and accurately simulate the hemodynamics of intracranial aneurysms.This method has the potential to provide effective support for clinical risk prediction in intracranial aneurysms.

Objective:To investigate the clinical characteristics of patients with high-myopia macular hole retinal detachment (MHRD) combined with choroidal detachment and to preliminarily analyze factors associated with postoperative hole closure.Methods:A retrospective clinical case series study. A total of 68 patients with high myopia (68 eyes) with MHRD diagnosed by Department of Ophthalmology, Peking University People’s Hospital from January 2019 to April 2024 were included in this study. Among them, there were 14 males (14 eyes) and 54 females (54 eyes). The mean age was (61.10±9.66) years. All eyes were treated with pars plana vitrectomy (PPV) combined with silicone oil or gas filling. Best corrected visual acuity (BCVA), intraocular pressure, and B-mode ultrasonography were performed. The BCVA test was performed using the Snellen visual acuity chart, which was statistically converted to logarithm of the minimum angle of resolution (logMAR) visual acuity. The range of choroidal detachment was defined according to the number of involved quadrants observed in B-mode ultrasound or surgery, which was divided into 1 to 4 quadrants. Axial length (AL) was measured under retinal reattachment. In 68 eyes, there were 17 eyes with choroidal detachment and 51 eyes without choroidal detachment, respectively. There were 17 eyes with choroidal detachment, and the detachment range involved 1, 2, 2 and 12 eyes in 1, 2, 3 and 4 quadrants, respectively. During operation, 13% C 3F 8 was filled in 2 eyes, all of which were not complicated with choroidal detachment. 66 eyes were filled with silicone oil. According to whether the patients were complicated with choroidal detachment, the patients were divided into the group without choroidal detachment and the group with choroidal detachment. Independent sample t test, Welch two-sample t test or Mann-Whitney U test were used for comparison between groups. Generalized linear regression and logistic regression were used to analyze the relationship between the aperture size of postoperative unclosed holes and the closed hole after surgery and clinical factors. Results:At 3 months after surgery, the logMAR BCVA of the affected eye was 1.29±0.43, with a preoperative to postoperative difference ranging from -1.60 to 0.70 (-0.51±0.51) logMAR units. The AL ranged from 26.6 to 34.3 (29.60±2.12) mm. Among 68 eyes, macular hole of 37 (54.4%, 37/68) eyes were open and 31 (45.6%, 31/68) eyes were closed, respectively. The hole diameter of the open eye was (753±424) μm. There was no significant difference in age, course of disease and AL between the two groups ( W=412.0, 477.5, 427.0; P>0.05). Before operation, BCVA in patients with choroidal detachment was worse ( W=257.5) and intraocular pressure was lower ( t=4.051) in patients with choroidal detachment compared with those without choroidal detachment, with statistical significance ( P<0.05). At 3 months after surgery, BCVA in patients with choroidal detachment was significantly worse than that in patients without choroidal detachment, with statistical significance ( W=284.0, P<0.05). There were no significant differences in logMAR BCVA difference ( t=0.616) and macular hole closure rate ( χ 2=0.000) before and after surgery ( P>0.05). The reoperation rate of retinal detachment due to persistent or recurrent retinal detachment was significantly higher in the group with choroid detachment than in the group without choroid detachment, and the difference was statistically significant (odds ratio=6.424, P<0.05). Logistic regression analysis showed that young age was significantly correlated with macular hole closure failure after surgery ( β=0.077, P=0.015). There was no correlation between AL, duration of disease, BCVA before surgery, intraocular pressure, wether combined with choroid detachment range and postoperative hole closure ( β=-0.072, 0.000, 0.672, -0.085, -0.391; P>0.05). Conclusions:Concomitant choroidal detachment adversely affected on both pre-operative and post-operative visual acuity in high myopia MHRD. It is closely associated with the risk of recurrent retinal detachment and the needs of multiple operations, but has no significant effect on hole closure rate. Lower age of onset may be a risk factor for macular hole closure.

Objective:To observe and analyze the correlation between ectopic foveal inner layer (EIFL) and the EIFL-based idiopathic epiretinal membrane (ERM) staging system and the anatomic and functional prognosis of ERM eyes post pars plana vitrectomy (PPV).Methods:A retrospective study. From January 1, 2020 to October 30, 2023, 345 eyes of 330 patients diagnosed with idiopathic ERM in Department of Ophthalmology of Peking University People's Hospital and treated with standard transciliary flat three-channel 25G PPV combined with ERM and internal limiting membrane exfoliation were included in the study. Among them, 96 were males (111 eyes) and 234 were females (234 eyes). The mean age was (66.8±7.7) years. All study eyes received standard three-port 25G PPV combined with ERM and internal limiting membrane peeling. All study eyes underwent best corrected visual acuity (BCVA) and optical coherence tomography (OCT) examinations. BCVA was performed using a standard logarithmic visual acuity chart and converted to logarithm of the minimum angle of resolution visual acuity for statistical analysis. EIFL thickness and central foveal thickness (CFT) on OCT were measured. ERM eyes were grouped into stage Ⅰ, Ⅱ, Ⅲ and Ⅳ according to ERM staging scheme based on EIFL; disorganization of the retinal inner layers (DRIL) of study eyes were assessed and grouped into no, mild and severe groups. The correlation between ERM staging as well as EIFL thickness and the anatomical and functional prognosis 6 months post-PPV were analyzed.Results:Among 345 study eyes, 12, 87, 174 and 72 eyes were stage Ⅰ-Ⅳ ERM respectively, 63 with no DRIL, 216 with mild DRIL and 66 with severe DRIL. Among the 153 eyes with macular edema, the edema subsided in 66 eyes (43.1%, 66/153) 6 months after the operation. Eighty-seven eyes (56.9%, 87/153) did not regress. The edema subsided 6 months after the operation was not significantly correlated with the ERM stage before the operation ( χ2=3.331, R=?0.145, P=0.304) or the degree of DRIL ( χ2=0.655, R=?0.108, P=0.445). The results of the correlation analysis showed that logMAR BCVA 6 months after the surgery was positively correlated with the degree of DRIL before the surgery ( Tau-b=0.236), ERM stage ( Tau-b=0.194), CFT ( r=0.383), and EIFL thickness ( r=0.317) ( P<0.05). There was no significant correlation with the thickness of the outer nuclear layer before the operation ( r=0.004, P>0.05). Preoperative ERM stage ( Tau-b=0.303, P<0.001) and DRIL severity ( Tau-b= 0.238, P=0.001) were positively correlated with CFT at 6 months after surgery. Conclusion:The ERM stage and EIFL thickness before the operation are positively correlated with logMAR BCVA and CFT 6 months after the operation.

Objective:To investigate the impact of body mass index (BMI) on delayed extubation of patients with acute Stanford type A aortic dissection (ATAAD).Methods:A total of 400 ATAAD patients who were admitted to our hospital from October 2021 to October 2023 and underwent surgical treatment were selected as the research objects. According to BMI, they were divided into obese group (BMI≥28 kg/m 2, 119 cases) and non-obese group (BMI<28 kg/m 2, 281 cases). The differences of preoperative clinical characteristics, intraoperative and postoperative data between the two groups were compared. Starting from transferring to the ICU and ending with the first successful extubation, The risk factors of postoperative invasive mechanical ventilation time ≥ 48 h in ATAAD patients were analyzed, and the predictive efficacy of related factors for postoperative invasive mechanical ventilation time ≥ 48 h in ATAAD patients was evaluated. Results:Compared with the non-obese group, the proportion of hypertension, diabetes, admission heart rate, admission systolic blood pressure, admission diastolic blood pressure and preoperative white blood cell count in the obese group were significantly increased, and the differences were statistically significant ( P<0.05). The cardiopulmonary bypass time, aortic cross-clamp time, operation time, red blood cell transfusion volume, invasive mechanical ventilation time, secondary operation rate and total hospitalization cost in the obese group were significantly higher than those in the non-obese group, and the differences were statistically significant ( P<0.05). Univariate logistic regression analysis showed that BMI, cardiopulmonary bypass time, ascending aortic cross-clamp time, operation time, age, hypertension, and red blood cell transfusion were related factors for postoperative invasive mechanical ventilation time ≥48 h in ATAAD patients ( P<0.05). Logistic multivariate regression analysis showed that increased BMI ( OR=1.213, P<0.05) and increased age ( OR=1.020, P<0.05) were independent risk predictors of postoperative invasive mechanical ventilation time≥48 h in ATAAD patients. Receiver operating characteristic curve ( ROC) analysis showed that the area under the ROC curve ( AUC) of BMI for predicting the duration of postoperative invasive mechanical ventilation in ATAAD patients≥48 h was 0.682 ( P<0.05), and the best predictive cut-off value was 25.64 kg/m 2. Conclusion:BMI≥28kg/m 2 increases the difficulty of surgery and the duration of invasive mechanical ventilation in ATAAD patients. BMI has a high predictive value for the duration of invasive mechanical ventilation in ATAAD patients after surgery ≥48 h, and effective intervention measures can be formulated to improve the treatment effect of patients.