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K H Hauenstein

Publications and source records attributed to K H Hauenstein.

At least 37 records · Page 2Linked to original sources
PubMed1992

[Digitization of conventional x-ray films].

The diagnostic value of a digitization system for analogue films based on a charge-coupled-device (CCD) scanner with adjustable resolution of 2.5 or 5 lp/mm was assessed. Some 110 skeletal radiographs, 50 contrast studies, including 25 of patients with Crohn's disease, and 70 abdominal plain films before and after successful lithotripsy for renal stones were digitized. Receiver operating characteristic (ROC) studies showed improved detection of cortical and trabecular defects with contrast-optimized digitized films. Edge enhancement algorithms yielded no additional information. Inflammatory lesions of Crohn's disease were detected equally well by conventional films and digitized images. A statistically significant improvement (p less than 0.05) in the recognition of disintegration after lithotripsy was found for the processed digitized images. On the basis of this initial investigation, the digitization system tested appears to be useful for diagnostic purposes, especially when contrast resolution plays an important part, as with stone fragmentation or cortical defects.

Bone Neoplasms↗
PubMed1992

[Uretero-arterial fistula. A rare cause of massive hematuria].

Ureteroarterial fistulae is a rare condition, with less than 25 reported cases. We describe such a fistula in a young female patient, after radiation therapy for cancer of the cervix and rectovaginal and vesicovaginal fistulae requiring sigmoidostomy and an ureteroureterostomy after long-lasting ureteral intubation. Angiography demonstrated the fistula and the reflux of contrast medium up to the pyelocalyceal cavities, and allowed establishing the origin of the massive hematuria, which caused the patient's death.

Adult↗
PubMed1992

[Percutaneous interventions on the bile duct in obstructive jaundice. A meaningful or excruciating prolongation of life?].

The percutaneous transhepatic access to the bile duct opens a wide spectrum of diagnostic and therapeutic procedures. This means specific diagnosis and therapy of the obstructive jaundice even in patients in bad general conditions and therefore unfavourable prognosis. As in most cases curative therapy is no longer possible, survival time can be taken into consideration. There are no great problems concerning the performance of technical procedures. But it is the justifiability of the interventions that has to be reconsidered in each of the cases. The facts that the quality of life can be improved and the possibility to discharge the patient as soon as possible should be the guidelines in having the patients undergo these therapeutic procedures. The evaluation of our case material from 1985-1991 show that just in this respect the introduction of the endoprosthesis (thick calibrated endoprosthesis, stents) is a great progress, with a mean survival time between 8 and 10 months, and with normalization of laboratory values in 75-100%.

Adult↗
PubMed1992

[Diagnostic procedures in acute gastrointestinal hemorrhage].

In gastrointestinal bleeding, the diagnosis is predominantly made by endoscopy. However, if the bleeding site is in a part of the intestine that cannot be reached by endoscopy, than the diagnosis is based on radiological and scintigraphic methods. In the past 5 years 35 patients with such cases of gastrointestinal bleeding had angiography and/or scintigraphy (n = 15) in our department. Based on our retrospective study of those cases, we advocate a management protocol for such patients based on the hemodynamic presentation.

Adolescent↗
PubMed1991

[Percutaneous transhepatic endoscopy and targetted tissue removal with an F-10.2 maneuverable thin cholangioscope].

Due to the flexibility and an external control mechanism of our thin calibrated cholangioscope (10.2 F) an inspection of the bile ducts via percutaneous transhepatic access is possible without too much discomfort for the patient. A 3.6 F working channel enables target-specific biopsies under optical control. It does not only enable histological diagnosis of the tumour itself but above all the exact definition of the proximal and distal tumour borders. This is a decisive criterion of operability and operation planning especially in tumours of the hepatic bifurcation. Expansion of the compressive lesion may be determined for palliative treatment. Percutaneous stone extraction by contact lithotripsy or with a Dormia basket is technically possible via the working channel under endoscopic view. An inspection of the peripheral branches of the same and the other liver lobe from one access only is made possible by easy maneuverability and flexibility of the endoscope.

Adenocarcinoma↗
PubMed1991

[Percutaneous transhepatic cholangioscopy for gallstone therapy and tumor diagnosis].

Using percutaneous-transhepatic cholangioscopy with a guided small calibre, cholangioscope (3.5 mm) in patients with obstructive jaundice it is possible to perform biopsies under visual control or to look for the exact intraductal extension of a tumor with only little stain on the patient. The access may be via a puncture of the right or the left hepatic duct. Since 1987 we have used this method 61 times in 45 patients. Some 32 patients suffered from malignancy of the bile duct. Of 13 patients with benign obstruction we performed a bougienage in 8. The other 5 patients were treated by stone extraction.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1991

[CT-guided biopsy. Comments on the puncture technique].

Computed tomography is an universally applied method of controlling diagnostic puncture of unrecognized processes in practically any region of the human body. The conditions required, the puncture technique, the various pathways and the types of needles used are discussed.

Biopsy, Needle↗
PubMed1991

[Percutaneous diagnosis and therapy of the bile ducts and gallbladder. Feasibility and status].

Percutaneous transhepatic access to the bile duct has opened up new possibilities not only for diagnosis by means of cholangiography and cholangioscopy with endoscopically guided biopsy by small-bore equipment, but also for the treatment of benign and malignant obstructive jaundice. In malignant disease recanalization of the obstruction is possible by means of laser, intracavitary irritation, internal bile drainage in Klatskin tumors, large-diameter endoprostheses (e.g., a Y-shaped prosthesis) or metal stents. In benign disease, balloon dilatation of inflammatory stenoses, stone extractions from the bile duct or gallbladder by means of Dormia baskets, ultrasound or piezoelectric shockwave-contact lithotripsy and chemical litholysis are possible. Very often percutaneous access is a real alternative to surgical intervention.

Bile Duct Diseases↗
PubMed1990

Diagnostic imaging in metastatic lung disease.

Chest radiographs, full lung tomography and computed tomography of the chest provide increasing sensitivity for evaluation of pulmonary metastases. Pulmonary nodules of 5-10 mm diameter are detectable with increasing frequency by use of high kilovoltage chest radiographs. Full lung linear tomography provides an overall accuracy of 72-97% in diagnosis of pulmonary nodules. Chest CT delineates pulmonary nodules as small as 3 mm within 10 mm slice sections. However, as sensitivity increases, specificity diminishes in identifying metastatic nodules. Sensitivity in CT is also reduced by false negative findings due to unequal respiratory cycles. Comparative radiologic-pathologic evaluation of nodule detection proved CT to be the most sensitive screening method for pulmonary metastases. Timing of follow-up studies for pulmonary nodule detection in cancer patients can be determined by tumor growth kinetics; 3-6 month intervals proved to be useful.

Humans↗
PubMed1990

[Wide-gauge bile duct endoprostheses with a port irrigation system. A new method of prolonging the drainage function].

The maintenance of adequate drainage by the bile ducts is crucial in all the endoscopic or percutaneous transhepatic procedures used today for the treatment of obstructive jaundice. We use wide-gauge polyurethane bile duct endoprostheses (F16; 5.3 mm - F20; 6.7 mm). Occlusion need not be expected to occur earlier than 4-6 months after placement. The implantation of a subcutaneous port system connected to the prosthesis by means of an F5 (1.6 mm) catheter allows not only X-ray examination of the function, but also lavage of the prosthesis and the biliary ducts. It is possible to add bile-dissolving substances, thus preventing crystallization of bile. In this way the patency of the prosthesis can be maintained for substantially longer. This also means a definite improvement in the quality of life.

Cholestasis↗
PubMed1990

[Computed tomographic-guided fine-needle biopsy of the pancreas for histology determination].

Computed tomography-guided fine-needle biopsies of the pancreas were performed in 54 patients. In 46/54 biopsies, the material obtained permitted a histological diagnosis despite the small external needle diameter of only 0.95 mm. The only complication was due to laceration of an artery of the transverse mesocolon. The prevalence of malignant tumors was 67%. Adenocarcinoma was diagnosed in more than 80% of all biopsies; rare findings were malignant carcinoid or centroblastic lymphoma. Benign tumors included mucinous adenocystoma and serous microcystic adenoma. Within the group of patients where pathologic-anatomic evaluation was possible, the sensitivity of fine-needle biopsy for malignant tumors was 87% and the specificity 100%. A positive needle biopsy diagnosis for a malignant tumor reduces the number of exploratory laparotomies needed and is helpful in the planning of surgery.

Adenocarcinoma, Mucinous↗
PubMed1988

Significance of early angiographic follow-up after internal thoracic artery anastomosis in coronary surgery.

The authors report about the radiological checking of the patency of the internal thoracic artery transplant in 75 patients with coronary artery disease, using intraarterial DSA in the early postoperative phase (between 6th and 8th postoperative day). The left or the right brachial artery was punctated and the contrast medium was injected at a dosage of 50 ml in counter-current. Only one angiogram series per patient was necessary to appraise the anastomosis and the perfusion of the bypass applied. In 5 patients a stenosis and in 4 patients an occlusion of the transplant could to be diagnosed. Early postoperative angiography enables quality control. In case of occlusion reoperation may be indicated.

Adult↗
PubMed1988

[Early postoperative control of internal thoracic artery-coronary artery anastomoses using intra-arterial DSA].

Early postoperative angiographic control is important for prognosis and medical therapy for patients undergoing coronary bypass surgery. Grafts from the internal mammary artery had been shown to be superior to venous bypasses for anastomoses to the left anterior descending coronary artery. Thus, the need for angiographic demonstration of graft patency and function is increasing. We report on the angiographic analyses of 73 patients after left internal mammary artery (LIMA) bypass surgery by filling of the graft via retrograde injection of contrast medium into the left brachial artery. In all cases the bypass, anastomosis and downstream vessel were clearly visualised. No complications or side effects were observed.

Adult↗
PubMed1988

[Limitations of computed tomographic differential diagnosis of focal liver changes].

Computed tomography of the liver is essential when there are discrepancies between ultrasonography, physical examination and laboratory findings. However, sometimes the referring clinicians overestimate the true accuracy of CT. Some of its major pitfalls include the limited spatial resolution and consequent false-negative results in the case of small focal lesions; further disadvantages are the inadequate contrast between a lesion and surrounding liver parenchyma, and limited specificity even in perfusion studies. When typical patterns in contrast and density of a cyst, hemangioma and focal nodular hyperplasia are present an accurate diagnosis is achieved. In atypical cases and in all other liver lesions further investigations will be necessary.

Diagnosis, Differential↗
PubMed1988

[Predictive value of magnetic resonance tomography in comparison with sonography and computed tomography in the diagnosis of focal liver lesions].

Ultrasonography and computed tomography are widely used for the diagnosis of focal lesions of the liver. However, the possibilities for tumor characterization and determination of potential malignancy are limited in many cases. Evaluation by magnetic resonance imaging shows a good correlation of relaxation time with the amount of stroma as a proportion of the total cell content of a lesion. This allows differentiation for a number of lesions. Thus, the combination of ultrasonography and magnetic resonance imaging could provide the ideal diagnostic procedure in many cases.

Adult↗