Objective To investigate the local anatomical characteristics of the cyctic duct and the feasibility of bile duct exploration through the cystic duct for stone removal and primary suture.Methods From February to September 2023,100 cases of secondary choledocholithiasis(SCL)were treated with laparoscopic transcystic common bile duct exploration(LTCBDE).During the operation,6 indicators were measured,including the direction of the gallbladder duct joining the common bile duct,the inner diameter of the gallbladder duct,the length of the gallbladder duct incision,the length of the gallbladder duct parallel to the common bile duct,the distance between the incised gallbladder duct or common bile duct and the upper edge of the duodenum,and the diameter of the stone taken by the cholangioscopy.Results The direction of the gallbladder duct joining into the common bile duct:92 cases at 9-12 o'clock,of which 76 cases at 10 and 11 o'clock,accounting for 76%;1 case each at 1 and 2 o'clock,accounting for 2%;2 and 4 cases at7 and 8 o'clock respectively,accounting for6%.The inner diameter of the cystic duct ranged from 3 mm to13 mm,with a median of 5.0 mm.The length of the common bile duct opened:21 cases(21%)had the common bile duct cut open,with an incision of 1-5 mm and a median of 3.0 mm.The parallel length of gallbladder duct and common bile duct:there was a parallel length of 2-40 mm and a median of 10.0 mm in36 cases.The distance between the incised gallbladder duct or common bile duct and the upper edge of the duodenum was5-20 mm,with a median of 15.0 mm.Intraoperative choledochoscope was used in 90 cases to remove stones,with a total of 128 stones removed.The diameter of the stones ranged from 1.5 mm to 22.0 mm,with a median of 5.0 mm.All the100 cases of LTCBDE were successful.A total of 83 cases(83%)were followed up for 3 months after surgery.After discharge,their appetite returned to normal,and they resumed normal life and work.There were no symptoms of bile duct stones such as abdominal pain,jaundice,or fever,and their liver function was normal.B-ultrasound showed a diameter of 5-10 mm for the common bile duct,with a median of 7 mm,and no postoperative stenosis.Conclusions Exploring the common bile duct through the cystic duct is feasible,with no or minimal damage to the common bile duct and no damage to the Oddi sphincter.It is the best way and surgical technique for laparoscopic exploration and stone removal via choledochoscope in SCL.

Objective To investigate the local anatomical characteristics of the cyctic duct and the feasibility of bile duct exploration through the cystic duct for stone removal and primary suture.Methods From February to September 2023,100 cases of secondary choledocholithiasis(SCL)were treated with laparoscopic transcystic common bile duct exploration(LTCBDE).During the operation,6 indicators were measured,including the direction of the gallbladder duct joining the common bile duct,the inner diameter of the gallbladder duct,the length of the gallbladder duct incision,the length of the gallbladder duct parallel to the common bile duct,the distance between the incised gallbladder duct or common bile duct and the upper edge of the duodenum,and the diameter of the stone taken by the cholangioscopy.Results The direction of the gallbladder duct joining into the common bile duct:92 cases at 9-12 o'clock,of which 76 cases at 10 and 11 o'clock,accounting for 76%;1 case each at 1 and 2 o'clock,accounting for 2%;2 and 4 cases at7 and 8 o'clock respectively,accounting for6%.The inner diameter of the cystic duct ranged from 3 mm to13 mm,with a median of 5.0 mm.The length of the common bile duct opened:21 cases(21%)had the common bile duct cut open,with an incision of 1-5 mm and a median of 3.0 mm.The parallel length of gallbladder duct and common bile duct:there was a parallel length of 2-40 mm and a median of 10.0 mm in36 cases.The distance between the incised gallbladder duct or common bile duct and the upper edge of the duodenum was5-20 mm,with a median of 15.0 mm.Intraoperative choledochoscope was used in 90 cases to remove stones,with a total of 128 stones removed.The diameter of the stones ranged from 1.5 mm to 22.0 mm,with a median of 5.0 mm.All the100 cases of LTCBDE were successful.A total of 83 cases(83%)were followed up for 3 months after surgery.After discharge,their appetite returned to normal,and they resumed normal life and work.There were no symptoms of bile duct stones such as abdominal pain,jaundice,or fever,and their liver function was normal.B-ultrasound showed a diameter of 5-10 mm for the common bile duct,with a median of 7 mm,and no postoperative stenosis.Conclusions Exploring the common bile duct through the cystic duct is feasible,with no or minimal damage to the common bile duct and no damage to the Oddi sphincter.It is the best way and surgical technique for laparoscopic exploration and stone removal via choledochoscope in SCL.

Objective To assess the filtration efficiency of two N95 filtering-facepiece respirators(FFRs)for the decomposition products of sulfur hexafluoride (SF6).Methods Two types of N95 FFRs (the particulate and the acid-proof respirators) were selected in this study.The decomposition products of SF6,including particles,hydrogen fluoride (HF) and sulfur dioxide (SO2),were measured under experimental condition by using TSI PortaCount Plus,fluorine ion-selective electrodes and spectrophotometer separately.The filtration efficiency was then calculated and compared.Results Both two models of N95 respirators had lowest filtration efficiency larger than 95％ for particles under airflow ranged from 10 to 95 L/min.When exposed to different concentrations of HF (low:0.00～ 1.99 mg/m3,middle:2.00～3.99 mg/m3,high:＞4 mg/m3),the acid-proof N95respirator was more effective than the particulate respirator (P＜0.05) with a filtration efficiency of 98.83％,99.08％,and 99.03％ versus 48.44％,45.71％,and 47.31％.For four SO2 concentration ranges (0.00～2.49 mg/m3,2.50～4.99 mg/m3,5.00-9.99 mg/m3,and ＞10.00 mg/m3),the acid-proof respirator showed a high filtration efficiency within exposure to 1.5 hours:95.73％,98.67％,98.14％,and 97.78％,respectively,when exposure duration extended to 4 hours,the filtration efficiency of the acid-proof respirator decreased to 91.97％,82.28％,70.12％,and 58.56％,respectively.Conclusion Both the particulate and the acid-proof N95 FFRs met national standards on the particulate filtration efficiency.The acid-proof N95 respirator demonstrates to be more effective in filtering HF and SO2 than the particulate respirator.The filtration efficiency could decrease to an unsafe condition under longer exposure duration,timely replacement of respirator is recommended at the workplace.

Objective To assess the filtration efficiency of two N95 filtering-facepiece respirators(FFRs)for the decomposition products of sulfur hexafluoride (SF6).Methods Two types of N95 FFRs (the particulate and the acid-proof respirators) were selected in this study.The decomposition products of SF6,including particles,hydrogen fluoride (HF) and sulfur dioxide (SO2),were measured under experimental condition by using TSI PortaCount Plus,fluorine ion-selective electrodes and spectrophotometer separately.The filtration efficiency was then calculated and compared.Results Both two models of N95 respirators had lowest filtration efficiency larger than 95％ for particles under airflow ranged from 10 to 95 L/min.When exposed to different concentrations of HF (low:0.00～ 1.99 mg/m3,middle:2.00～3.99 mg/m3,high:＞4 mg/m3),the acid-proof N95respirator was more effective than the particulate respirator (P＜0.05) with a filtration efficiency of 98.83％,99.08％,and 99.03％ versus 48.44％,45.71％,and 47.31％.For four SO2 concentration ranges (0.00～2.49 mg/m3,2.50～4.99 mg/m3,5.00-9.99 mg/m3,and ＞10.00 mg/m3),the acid-proof respirator showed a high filtration efficiency within exposure to 1.5 hours:95.73％,98.67％,98.14％,and 97.78％,respectively,when exposure duration extended to 4 hours,the filtration efficiency of the acid-proof respirator decreased to 91.97％,82.28％,70.12％,and 58.56％,respectively.Conclusion Both the particulate and the acid-proof N95 FFRs met national standards on the particulate filtration efficiency.The acid-proof N95 respirator demonstrates to be more effective in filtering HF and SO2 than the particulate respirator.The filtration efficiency could decrease to an unsafe condition under longer exposure duration,timely replacement of respirator is recommended at the workplace.