Percutaneous Transhepatic Biliary Metallic Stent Placement: Experimental And Clinical Study

Malignancies of the biliary hilum have an extremely poor prognosis,with less than 10%of patients surviving 5 years after the diagnosis.This tumor is characterized by its deep spread into the liver along the periductal lymphatics and perineural spaces as well as along the bile duct wall.The resectability rates for high bile duct tumors are generally reported to be approximately 10%-20%,although rates as high as 96.5%, with 50.9%undergoing radical resection,have been reported.For the vast majority of patients,palliation is the goal.Although surgical bilioenteric bypass has been the traditional palliative approach,this therapy cannot be applied to all patients,and surgical mortality rates have been reported to be as high as 33%when extensive resections are required.Percutaneous palliation of biliary obstruction resulting from hilar malignancy can be accomplished in a variety of ways.Various self-expanding metallic stents with differing constructions have been available for the treatment of malignant biliary strictures.Although it is still controversial whether all segments of the liver should be drained,the concerns regarding unilateral drainage include the inability to relieve jaundice and the potential for bacterial contamination of an undrained segment,with the possibility for subsequent biliary sepsis and death. Bilateral percutaneous transhepatic biliary drainage(PTBD) has been performed with placement of multiple stents with unilateral or bilateral transhepatic approaches. Several techniques to drain the right and left hepatic ducts via a single percutaneous tract have been developed to eliminate the additional morbidity and discomfort associated with a second PTBD procedure. Part 1:Percutaneous Transcholecystic Biliary Metallic Stent Deployment:feasible study in the canine and the pathology of the stented bile duct.PURPOSEthe purpose of this study was to report our initial experiment with a canine model for biliary metal stent implantation through a percutaneous transcholecystic access.MATERIALS AND METHODSTen dogs,weighing 22.5-29.5kg,fasted for 24h then anesthesia.After computer tomography guidance,the canines' gallbladders were punctured percutaneously under ultrasound.Omnipaque was given to opacity the gallbladder and extrahepatic biliary system.Using an Introducer Set and superstiff wire,a 5F sheath,with a length of 30 cm, was placed through the cystic duct into the common bile duct.Then mental stents were deployed into the common bile duct through cystic duct.Follow-up one month with CT scan and chemistry test.Autopsy was performed after one month to evaluate the safety and feasibility of this animal model.RESULTSPuncture of gallbladder was successful in all ten dogs Metallic stents were successfully deployed into eight dogs,while the other two were failure because of the sharp angulation of cystic duct and common bile duct.Seven animals tolerated the whole procedures(including deploying the metal stent) without changes in their clinical conditions and no symptoms.One died of bile leakage.At the 1-month follow-up,the hepatic function was within the normal range in four of the dogs.Alkaline phosphatase (AKP) increased from 5 to 10 days after operation in two of dogs and total bilirubin increased in one dog.These abnormalities recovered one month later.There was no obvious migration for all stents during the follow-up period,which was evaluated by CT scan.CONCLUSIONSThis technique allows a safe and feasible access into the biliary system using a percutaneous transcholecystic approach especially for a long-term interventional research.Part 2:The Clinical Study of Metallic Stents in the Treatment of Complex Hilar CholangiocarcinomaPURPOSETo evaluate the technical success and clinical efficacy of multi stents placement in the management of hilar cholangiocarcinoma.MATERIALS AND METHODS45 consecutive patients with hilar cholangiocarcinoma were treated with percutaneous transhepatic placement of two or three self-expandable metallic endoprostheses in a different configuration.These patients ranged in age from 39 to 79 years and included 27 men and 18 women.The cause of hilar obstructions in these patients are all cholangiocarcinoma included Bismuth classification wereâ…¡(n=12),â…¢a (n=17),â…¢b(n=10),andâ…£(n=6).All patients were considered unsuitable candidates for surgical resection on the basis of medical fitness,tumor extent,or both,and endoscopic attempts to drain the right and left hepatic ducts had been unsuccessful in some patients.All PTBD procedures were performed with use of sonographic and fluoroscopic guidance by way of a left ventral or right lateral approach,or both.The stents used in this study were self-expanding nitinol stents(Antai Company,BEJING). All stents were placed 3-7 days after the initial drainage procedure.Then 2 or 3 stents were placed in the configuration of T,Y or X over the stricture.Three days after stent placement,contrast material was injected to confirm the position and patency of the endoprostheses,and external drainage catheters were removed in all patients.The study endpoints were followed at monthly intervals during the follow-up periods.Medical records were reviewed,ultrasonography(US) or computed tomography(CT) of the liver was performed,and serum bilirubin levels were checked.Technical success was defined as the deployment of the endoprostheses across the stricture with good radiologic positioning and bile passage down the stent.Successful decompression of the biliary system was defined by a decrease in serum bilirubin level more than 30% versus baseline value within the first week after stent insertion.In cases of recurrent jaundice,patients were evaluated by US,percutaneous transhepatic cholangiography, or CT.At the time of death,the stent was considered to be patent if the patient had a normal bilirubin level or stable mild hyperbilirubinemia.Complications were also evaluated with medical records and laboratory data.Statistical analysis was performed with use of SAS software(version 8.1) and SPSS(version 11.0).Stent patency rate and patient survival rate were calculated according to the Kaplan-Meier method.A Cox proportional-hazards model was used to assess differences affected by age,sex,or Bismuth type of obstruction.RESULTSStent placement with two or three endoprostheses was successful in all patients. Follow-up cholangiograms on the third day after stent placement showed that the system was adequately decompressed in all cases.All patients showed a significant decrease in serum bilirubin level.A paired t test of pre-and post procedural mean bilirubin levels showed a P value less than 05,which was considered statistically significant.All patients were free of external drainage tubes after the stent insertion. There were no major complications directly related to stent insertion.The usual complications of self-limiting hemobilia and cholangitis were associated with initial biliary drainage or dilation of the tract.No related to the procedure.The mortality rate within 30 days of stent placement was 2.2%(1 of 45).The mean survival and stent patency times were 215.3 days(range,26-516 days) and 181.5 days(range,26-473 days),respectively.There were no statistical differences in age,sex,or Bismuth type.CONCLUSIONSMulti stents placement is simple,safe,and reliable in achieving bilateral internal bile drainage in patients with complex hilar cholangiocarcinoma.Part 3:The Clinical Study of Percutaneous Intervention in the Treatment of Obstructive Jaundice due to Bile duct thrombosisPURPOSETo explore the Percutaneous Intervention in treatment of obstructive jaundice due to bile duct thrombosis in order to improve clinical efficacy and patients' quality of life.MATERIALS AND METHODS27 patients with obstructive jaundice due to bile duct thrombosis,ranged in age from 32 to 82 years and included 22 men and 5 women,were caused by hepatic cellular cancer(19 cases),carcinoma of gallbladder(4 cases),rectal cancer(1 case) and gastric cancer(3 cases).It was proved by operative pathology for 16 patients,punture biopsy for 5 patients,bile duct biopsy forceps for 3 patients and combination of clinical, biochemistry and imaging for 3 patients.The bile duct thrombosis included Ueda classification were typeâ…¢for 23 cases(85.2%) and 4 cases(14.8%).All patients were treated with percutaneous transhepatic biliary drainage. Permanent external drainage was prefered when the internal drainage associated with hemobilia and cholangitis.Stent placement was chosed if jaundice and other symptoms were improved.Internal drainage tube was remained accompanied with reccurence of symptoms.RESULTSPTBD was success in all cases.The procedures were preferd as below:Permanent external drainage for 5 patients,internal drainage and adjustment for 13 patients, covered stents for 7 patiens,stents placement with external drainage for 2 patients because of hemobilia and cholangitis who died 30 days later.Complications: immediate hemobilia due to puncturation for 7 cases(25.9%),hemobilia post-operation duration for 19 cases(70.4%),drainage tube falling off for 2 cases(7.4%).The conditions were sovled with corresponce treatment.Quality of life was considered to be improved for 23 patients(85.2%) Because symptoms of fever and jaundice was improved,better weight And appetite and self-confidence to fight against disease was elevated.The mean survival time and median survival time were 109.3 days(range, 17-320 days) and 92 days,respectively.CONCLUSIONSPercutaneous Intervention is one of choices to improve the patients' quality of life in case of unresectable bile duct thrombosis.Covered stent was prefered with typeâ…£thrombosis,choice of covered stent,external drainage and internal drainage for typeâ…¢adjusted correlated with different conditions,bare metalic stent was unsuitable for bile duct thrombosis.