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T Ponchon

Publications and source records attributed to T Ponchon.

100 records · Page 6Linked to original sources
PubMedDate not supplied

Retrograde biliary ultrathin endoscopy enhances biopsy of stenoses and lithotripsy.

Forceps biopsies of biliary stenoses are difficult to direct under fluoroscopy and for this reason may give spurious results. In addition, fluoroscopy does not prevent the electrohydraulic lithotripsy (EHL) probe from damaging the bile duct wall. Retrograde biliary endoscopy with the ultrathin endoscope (UTE) was tested in 12 patients to guide biopsies and in 6 patients to guide EHL. Results of biopsies were confirmed by surgery or the disease course in each of the 12 patients. Only one stone could not be fragmented and removed because the EHL probe could not be properly placed. The diagnosis of biliary stenosis may be markedly enhanced by using a UTE although at the risk of an endoscopic sphincterotomy and subsequent biliary infection. EHL with UTE is difficult and time consuming but further technical development may make it more practical immediately following sphincterotomy.

Aged↗
PubMedDate not supplied

Endoscopic treatment of biliary tract fistulas.

Endoscopic therapy was attempted in 24 patients with spontaneous or postoperative persistent biliary fistulas. Endoscopic retrograde cholangiography demonstrated the site of the fistula in 22 cases. Sphincterotomy or biliary stent placement resulted in rapid resolution of the fistula in 16 of 24 patients. Failures were attributed to exclusion of the injured intrahepatic bile duct in two cases, insufficient dilation of a bile duct stricture in one, the large size of the bile duct defect in two, and associated lesions in three (cirrhosis, arterial trauma, subhepatic abscess). Endoscopic management of biliary fistulae requires: (1) visualization of the location of the fistula by retrograde cholangiography especially in case of an intrahepatic lesion, (2) prior percutaneous drainage of associated subhepatic or subphrenic abscesses, and (3) appropriate relief of distal biliary obstruction in order to reduce the intraductal biliary pressure. The outcome is uncertain when endoprostheses are used to bridge large bile duct defects.

Adult↗
PubMedDate not supplied

Extracorporeal ablation of liver tissue by high-intensity focused ultrasound.

High-intensity focused ultrasound (HIFU) may produce a well-delineated lesion of coagulation necrosis in deep organs, by means of an extracorporeal transducer. Applications of this method to the liver in animal models have been studied for many years. The effects of HIFU on the normal liver parenchyma and on hepatic tumors are reviewed. In the normal rabbit liver in vivo we showed the relation between intensity levels and exposure times and the need to adapt intensity to the depth of the target. No severe complications were observed when an intensity of 1,000 W/cm2 was used. HIFU is a noninvasive method for the local destruction of liver tumors. In experimental models, safety and efficacy were demonstrated. HIFU may be interesting for the treatment of some human liver tumors.

Animals↗
PubMedDate not supplied

[Cephalic duodenopancreatectomy for endocrine tumor of the ampulla of Vater and of the minor papilla].

OBJECTIVES: Endocrine tumors of the ampulla of Vater and minor papilla are rare. This study describes the mode of presentation and evaluates the correlation between pathological features and prognosis. PATIENTS: Between 1982 and 1998, 6 patients (3 M, 3 F, mean age: 47.6 years, range: 36-58) for whom a diagnosis of endocrine tumor of the ampulla of Vater or minor papilla was made between 1982 and 1998 after histological examination of an operative specimen of pancreaticoduodenectomy. RESULTS: One patient was detected incidentally, two had a Zollinger-Ellison syndrome, two had pain and one had obstructive jaundice with pain. The tumor was located in the ampulla of Vater in 5 cases and at the minor papilla in 1 case. All patients underwent a pancreaticoduodenectomy, with histological examination showing tumor diameter varying from 5 to 40 mm and positive lymph nodes. Five patients had a well differentiated endocrine tumor and one a poorly differentiated tumor. All patients had positive Grimelius staining. The secretory profile analyzed by immunohistochemistry was heterogeneous. Median duration of follow-up was 51 months (range: 6 months-16 years) with all patients currently still alive. The patient with a poorly differentiated tumor had diffuse liver metastases, the others were disease-free. CONCLUSION: This study demonstrates the frequency of metastatic spread to adjacent lymph nodes and the inconsistent secretory profiles of these tumors. Pancreaticoduodenectomy may offer long term disease-free survival in well differentiated tumors, and such histology may be useful in advising on prognosis.

Adult↗
PubMedDate not supplied

[Value of intraductal biopsies and intraductal cytology in the etiological diagnosis of biliary stenoses].

Endobiliairy tissue specimens were obtained for cytologic and histologic examinations at the site of stenosis after percutaneous biliary drainage or endoscopic retrograde sphincterotomy in 49 patients with benign (10 cases) or malignant (39 cases) biliary stricture. Final etiologic diagnosis was obtained by surgery (18 cases), autopsy (one case), aspiration cytology of metastasis (2 cases), serology (2 cases), and in 26 cases, was determined by the course and outcome of the disease. As the sensitivity of each method, cytology and histology, was weak, it was necessary to associate them to improve results. Accurate etiologic diagnosis was achieved in 77 p. 100 of cases. The specificity of the method was satisfactory and specimen examination allowed to correct and confirm the initial etiologic diagnosis in 12 and 65 p. 100 of cases, respectively. The specificity of the method and its low morbidity prompt us to recommend it during transhepatic or retrograde therapeutic drainage as it can serve as a guide for later treatment. On the other hand, achievement of a transhepatic drainage or an endoscopic sphincterotomy only to obtain endobiliairy tissue specimens means taking into account the poor sensitivity of the method and the complications inherent to transhepatic drainage and endoscopic sphincterotomy. The practice of obtaining specimens by the retrograde technique without sphincterotomy or under cholangioscopy should be developed.

Adult↗