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Biomedical subjects

M Classen

Publications and source records attributed to M Classen.

At least 343 records · Page 19Linked to original sources
PubMed1984

[Active immunization against hepatitis B].

The efficacy of the hepatitis B vaccine Hevac B Pasteur was assessed in 277 persons over a period of 6 months. HBs antigen of 5 micrograms/dose was administered three times in monthly intervals. Before each vaccination and after 6 months 18 chemical pathology data and a clinical assessment were performed and all important serologic hepatitis markers (anti-HBs, anti-HBc, HBs antigen, HBc antigen, anti-HBe) were determined radioimmunologically. Within two months antibodies against the surface antigen (anti-HBs) had developed in 85.7% of vaccinees. After 6 months 93.1% of vaccines had become seropositive. Within the first two months anti-HBs-positive findings and higher anti-HBs concentrations occurred significantly more frequently (P less than 0.048) in females than in males. These differences had largely disappeared at the follow-up assessment in the sixth month. In contrast, both parameters (seroconversion rate and anti-HBs concentration) were age-dependent. Among vaccines of less than 25 years of age and of more than 35 there were significant differences after 6 months (P less than 0.005). The hepatitis B vaccine of the Pasteur institute can be considered immunogenic and safe.

Adult↗
PubMed1984

[Viral hepatitis B markers in physicians and medical personnel in the Rhein-Main region].

HBs antigen, anti HBs and anti HBc were determined radioimmunologically on 314 medical students, 585 doctors, 151 medical laboratory personnel and 307 nursing staff. Hepatitis B markers were present in 5.1% of medical students, 23.4% of doctors, 17.9% of laboratory personnel and 18.6% nursing staff. In the different groups there were up to 1.3% HBs antigen-positive persons. A large majority of persons with signs of previous hepatitis B infection had concentrations of both antibodies (anti-HBs and anti-HBc). Between 0.6 and 5.5% of persons were merely anti-HBc positive. Among doctors the number of positive results increased with age and professional exposure, no age dependence as to seropositive or seronegative being found in the other groups. None of the persons tested had been aware of a preceding hepatitis infection. These results indicate that doctors and medical personnel even today are at risk of an undetected viral hepatitis B.

Adult↗
PubMed1984

[Endosonography using a gastrofiberscope].

Gastroscopic ultrasound tomography enables a direct sonographic approach to the upper gastrointestinal tract and the surrounding organs. First experiences show that this new method is characterised by a great diagnostic potential. Its advantages compared with conventional sonography are the avoidance of sonographic obstacles and an improved recognisability of details; part of the examined area is, so to say, enlarged due to the use of high ultrasonic frequencies. With an ultrasonic frequency of 7.5 megahertz, the following processes can be visualised more clearly than with conventional sonographic equipment: processes in the pancreas, cholelithiasis of the common bile duct, hepatic foci, processes in the splenorenal angle, as well as tumours of the stomach and of the esophagus. In cardiology, clear indications are easily recognised, such as the atrial septal defect.

Common Bile Duct Diseases↗
PubMed1984

Electronic endoscopy of the gastrointestinal tract. Initial experience with a new type of endoscope that has no fiberoptic bundle for imaging.

We report on 31 endoscopic investigations using a new type of electronic endoscope which has no fiberoptic bundle for imaging. The device carries on its tip a light-sensitive CCD chip which functions as a TV camera. The signals received are transformed by a processor and displayed on a TV monitor. The upper digestive tract was inspected in 23 patients with the electronic endoscope and in the same session, a fiberoptic-endoscopic esophagogastroduodenoscopy was carried out on 16 of them. The information obtained using the 2 systems differed neither quantitatively nor qualitatively. Because of its external diameter, it was not possible to introduce the electronic endoscope past esophageal stenoses in 2 patients. Preliminary experience with 2 types of colonoscopes in 8 patients strongly indicates that these devices are equivalent, in respect of optical quality, to the fiberoptic endoscopes. The quality and color reproduction of the TV image of the upper and lower digestive tract are excellent. Electronic endoscopy offers great potential for consultation, training and documentation. The patients tolerated the procedure very well.

Adult↗
PubMed1984

Pancreatography in chronic pancreatitis: international definitions.

Terminology in classification of pancreatograms was discussed at a recent international workshop on chronic pancreatitis. A new terminology based on morphological radiographic appearances and a new classification to describe the severity and localisation of pancreatogram changes were agreed. Pancreatograms in chronic pancreatitis are graded as normal or equivocal, or as showing mild, moderate, or marked changes, either diffuse or local. It is hoped that these definitions will help communication between centres, serve as a basis for prospective and comparative studies, and facilitate computerisation.

Chronic Disease↗
PubMed1984

Investigations on the toxicity of bile salt solutions, Capmul 8210 and a bile salt-EDTA solution for common bile duct perfusion in dogs.

The following perfusion media for dissolving bile duct calculi were infused via a cutaneobiliary tube into the biliary tract of 12 mongrel dogs: 4.3% cholate solution, 0.34% chenodeoxycholate solution, Capmul, GMOC (special formulation of Capmul), BA-EDTA and 0.9% saline. Infusion lasted 50 h. Postmortem examination revealed hemorrhagic, partly phlegmonous cholangitis, acute duodenitis, necrosis and abscesses in the liver. The lesions were most pronounced after the cholate solution and with Capmul and GMOC, but were only detected to a slight extent after BA-EDTA and the chenodeoxycholate solution. 0.9% saline had no side effects. The investigations could demonstrate that it is the very irrigation media that today are recommended for treatment of bile duct stones in patients, that cause considerable morphologic side effects. The alternating administration of an EDTA solution with a Capmul preparation may diminish local toxicity of the latter.

Animals↗
PubMed1984

Somatostatin-containing cells in the extrahepatic biliary tract of humans.

We investigated the presence of endocrine cells in the human extrahepatic biliary system using the avidin-biotin-peroxidase complex method. Twenty gallbladders obtained during operations for cholelithiasis, large portions of three common bile ducts obtained during Whipple's procedure for carcinoma of the head of the pancreas, and 155 endoscopic transpapillary biopsy specimens taken during control endoscopy from patients who had had a previous endoscopic sphincterotomy were examined. Somatostatin-containing cells were found in the glandular epithelium of the ampulla of Vater and the bile ducts. Only the surface epithelium in the ampulla contained endocrine cells. All somatostatinlike immunoreactivity was confined to cells and could not be detected in nerves. No somatostatinlike immunoreactivity was found in the gallbladder. These findings reveal a morphologic basis to reported actions of somatostatin on bile flow.

Ampulla of Vater↗
PubMed1984

Radiological and ultrasonographic investigations with respect to patient selection and monitoring for chemical gallstone dissolution.

786 consecutive patients with suspected gallstones investigated radiologically and ultrasonographically, 231 (33.0%) were found to have stones. Radiological examinations showed that 59.3% of these were suitable for chemical dissolution with cheno- or ursodeoxycholic acid. The percentage of treatable patients fell from age 20 to age 65 from 71% to 48% (p less than 0.05) and then rose again to 61% (not significant). The benefit of litholysis is greater, the earlier it is begun. The results are in disagreement with those of two studies in operated patients. Here only 19-24% were suitable for stone dissolution. Comparative ultrasonographic and radiological studies in 23 patients have shown that monitoring of patients during litholysis can be carried out ultrasonographically. Stone size measured ultrasonographically corresponds sufficiently accurately with that obtained radiographically.

Adult↗
PubMed1984

[New technics].

Explore the source record for details and available documents.

Endoscopes↗
PubMed1984

Detection of atrial and ventricular septum defects by transoesophageal two-dimensional echocardiography with a mechanical sectorscanner.

Two-dimensional (transthoracic) echocardiography (2DE) and two-dimensional endoscopic (transoesophageal) echocardiography ( 2DEE ) were performed in 19 consecutive patients with atrial septum defect (ASD), and in 17 controls, 3 with ventricular septum defect (VSD) and 14 with various diseases. In detection of ASD the sensitivity was 61% (11/18) and the specificity 88% (2/17) with 2DE whereas 2DEE revealed a sensitivity of 95% (18/19) and a specificity of 100% (0/17). 2DEE enabled to visualize the VSD in all 3 patients (2DE in 1/3). With 2DEE the site and size of the atrial septum defects could be estimated well as confirmed in 14 patients who underwent cardiac surgery. The lateral resolution of the 7.5 MHz transoesophageal probe was about 0.5 cm. Further studies are required to clarify if cardiac catheterization prior to surgery of an ASD may be replaced by 2DEE .

Adult↗
PubMed1984

Anatomical aspects in ultrasonic endoscopy.

The combined use of gastroscopy and sonography will yield both methods an enhancement of its diagnostic range. By this new method, ultrasonography has to face new aspects of the examination. Endosonographical examinations were performed in 26 normal patients. The technique of endoscopic ultrasound tomography ( EUT ) is complicated and different because of the orientation, the predestined nature of the GI tract, and the limited movements within the GI tract. Seven standard positions are proposed: distal duodenum, papilla Vateri, bulbus duodeni, antrum ventriculi, corpus ventriculi, fundus ventriculi, and distal oesophagus. But up to now, there has been no general examination technique for the visualization of the individual organs. Nevertheless, with EUT new sonographic windows were opened. The first experiences show that the contours of organs and vessels may be imaged with a distinction unknown up to now. The sector and magnifying effect of EUT may contribute to the knowledge of anatomical, topographical and pathological conditions and changes.

Adult↗
PubMed1984

Detection of biliary stones by means of endosonography.

For its particular qualities, endoscopic ultrasound tomography ( EUT ) appears to be a suitable method for achieving better results in diagnostics of bile duct alterations than conventional UT. In 10 patients with enlarged common bile duct. EUT was carried out with three different prototypes (mechanical sector scan, ultrasound gastrofiberscope . Olympus/ Aloka ). The encouraging results suggest that the high discriminating investigational technique of EUT may be superior to conventional UT for finding common bile duct stones, probably for the differential diagnosis of biliary drainage problems caused by tumors, too.

Adult↗
PubMed1984

Pancreatic pseudocysts and tumors in endosonography.

In endoscopic ultrasound tomography (UT), the ultrasound probe positioned in the stomach has direct access to the pancreatic region. In first experiences, 62 patients were investigated by EUT . 22 of them had a pancreatic infection. EUT seems to be a new method being a valuable complement to conventional UT with a high diagnostic potential and with broad possibilities of application. The increased resolution of structural details of pathological alterations could be of diagnostic value.

Adult↗
PubMed1984

Diagnostic efficacy of endoscopic ultrasound tomography in pancreatic cancer and cholestasis.

By direct access to the target organs and by improved detail resolution, endoscopic ultrasound tomography (EUT) broadens the range of sonographic diagnostics. In this preliminary study, the accuracy of EUT was tested in 34 patients with suspected pancreatic carcinoma and/or painfree jaundice. In all 10 patients with pancreatic carcinoma and in all 6 patients with chronic pancreatitis, the diagnosis made by EUT was correct. Three patients with benign tumors of the pancreas were also diagnosed correctly. The diagnostic sensitivity of EUT in pancreatic cysts was in 4 of 5 cases 80%, in dilatations of the main pancreatic duct in 10 of 11 cases 91%, and in cholestasis in 14 of 15 cases 93%. All 5 common bile duct concrements and all 3 tumors of the papilla Vateri were diagnosed by EUT. The differential diagnosis between pancreatic tumor and pancreatitis was improved by EUT in 1 of 18 cases. In the region of the papilla Vateri, EUT was superior to conventional UT in the diagnosis of ampullary concrements and papillary tumors in 6 of 8 cases (4/5 and 2/3, respectively). EUT could become an important complementary diagnostic method for disorders of the pancreas and the common bile duct with a particular sensitivity for the region of the papilla Vateri.

Adult↗
PubMed1984

Endoscopic biliary drainage.

Endoscopic drainage of the occluded biliary system through the papilla Vateri consists of two different methods, i.e. bilio- nasal and bilio-duodenal drainage. For bilio-nasal drainage a 250-cm- long preformed polyethylene tube is placed above the stenosis to provide the flow out of the congested bile duct. This external drainage is indicated to prevent the blockade of a ductal stone after endoscopic papillotomy (EPT), to treat septic cholangitis, and to dissolve big ductal stones chemically. Insertion of a bilio-nasal probe succeeds in 95% of hte cases. Internal bilio-duodenal drainage is more difficult and succeeds in 87%, its main indication is the inoperable malignant bile duct obstruction. The value of a preoperative biliary drainage is in discussion. Internal bilio-duodenal drainage will perhaps not prolong the survival time of patients with malignant biliary obstruction but it will improve the life quality in the majority of the patients. The decrease of serum bilirubin after the implantation of the prosthesis and the localization of the tumor are of prognostic significance.

Bile Duct Diseases↗