Biomedical subjects
Publications and source records attributed to W S Rau.
We report a case of metastatic renal cell carcinoma arising in a cadaver transplant kidney 6 years after transplantation. Due to molecular analysis of the tumor tissue we could prove that the carcinoma originated from the male donor. After tumor resection and interruption of immunotherapy, the concomitant bone and lymph node metastases resolved with alpha-interferon and interleukin-2-based immunotherapy.
PURPOSE: In glenohumeral instability, CT arthrography and MR arthrography of the shoulder joint were compared to assess accuracy in diagnosis of labral lesions and other internal derangements of the joint, and to evaluate relevance of both imaging methods for therapy. METHODS: 38 patients with symptoms of shoulder instability were examined clinically, arthrographically with CT and MRI, and arthroscopically. Arthrography with CT and MRI was performed in a double-contrast technique after single puncture and simultaneous injection of the contrast agents for both imaging methods. Type and extent of lesions on arthrographic imaging were criteria for planning therapy to a conservative, sole arthroscopic, or open surgical approach. RESULTS: Sensitivity in diagnosis of labral lesion (26 defects) was 85% in CT, 88% in MRI and 100% if both methods were used. Full-thickness tears of the rotator cuff were visualised in CT in 73%, and in MRI in 100%. Diagnostic accuracy increased from partial to complete to total defects. An open surgical approach was correctly predicted on MRI in 90% and on CT in 71%. A sole arthroscopic therapy was correctly foreseen on both arthrographic techniques in only 38% due to difficulties to assess glenohumeral ligaments. CONCLUSIONS: CT arthrography and MR arthrography were excellent for diagnosing labral lesions. MRI is superior to CT in the imaging of all joint structures. Surgical approach can be accurately predicted with both imaging methods but special surgical techniques cannot be effectively planned to replace diagnostic arthroscopy in all cases.
PURPOSE: The aim of the present study was to evaluate the efficacy of fluoroscopically controlled implantation of subcutaneous tunneled single- or double-lumen-catheters for short- and long-term dialysis. PATIENTS AND METHODS: In total, 104 patients were implanted with either a single-lumen Demer catheter or a Permcath double-lumen catheter into the subclavian vein under fluoroscopic control. RESULTS: In 99 of 104 cases (= 95.2%) the implantation remained without complications. Implantation-related occurrences included one pneumothorax, one mediastinal haematoma and one death. 61.5% of the indwelling catheters remained in situ for the intended duration. In 78% of the patients, dialysis was carried out to completion. 37 explantations (38.3%) were required due to various factors including infection (5), thrombosis (3), dislocation (9) and malfunction (20). The average duration of implantation was 59.1 days (range 1-851 days). CONCLUSIONS: Fluoroscopic-controlled implantation of subcutaneous tunneled catheters for dialysis is superior to surgically implanted catheters with regard to lower rates of infections and is equally reliable in respect of rates of complication and patency. Thus, this mode of implantation is a safe and reliable alternative to other procedures as access for haemodialysis.
PURPOSE: An experimental study was performed on joint specimens of the knee to assess the advantages and disadvantages of 14 generally available sequences in cartilage imaging. METHODS: Each of the 50 surgically exposed cadaveric joints of the knee was examined by the following sequences: T1, proton- and T2 weighted spin echo(SE) sequences, proton- and T2 weighted Turbo-SE, T1 weighted SE with fat suppression, MTC combined with T1-weighted SE and T2 weighted FLASH-2 D, STIR, FISP-3 D, FLASH-3 D (with fat suppression), and MR arthrography. We assessed the image quality by a scale, signal to noise-ratio of cartilage and joint fluid, and the accuracy in detection of cartilage lesions. Pathology and arthroscopy were reference methods to MRI, and demonstrated grade 1-4 lesions on 186 of 300 joint facettes. RESULTS: Advanced stages of cartilage lesions (65 grade 3 and 4 lesions) were detected by standard SE sequences in 67-94%. Application of volume techniques (FISP-3 D, FLASH-3 D), high definition matrix (512 pixel), MTC with FLASH-2 D and MR-arthrography improved the sensitivity up to 82-100%. Superficial lesions (65 grade 2 lesions) were demonstrated in 3-38%, and on MR arthrography in 45%. Structural changes (56 Grade 1 lesions) were recorded on MR) in only 10%. CONCLUSIONS: With regard to standard SE sequences, the detectability of cartilage lesions can be improved by techniques that use 512 matrices, selective cartilage imaging, and volume acquisition.
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PURPOSE: Computed quantification of the extent of pleuropulmonary trauma by CT and comparison with conventional chest x-ray--Impact on therapy and correlation with mechanical ventilation support and clinical outcome. METHOD: In a prospective trial, 50 patients with clinically suspicious blunt chest trauma were evaluated using CT and conventional chest x-ray. The computed quantification of ventilated lung provided by CT volumetry was correlated with the consecutive artificial respiration parameters and the clinical outcome. RESULTS: We found a high correlation between CT volumetry and artificial ventilation concerning maximal pressures and inspiratory oxygen concentration (FiO2, Goris-Score) (r = 0.89, Pearson). The graduation of thoracic trauma correlated highly with the duration of mechanical ventilation (r = 0.98, Pearson). Especially with regard to atelectases and lung contusions CT is superior compared to conventional chest x-ray; only 32% and 43%, respectively, were identified by conventional chest x-ray. CONCLUSION: CT allows rapid classification and quantification of pulmonary lesions after thoracic trauma and provides higher sensitivity and reliability. Because of the great correlation with the extent of artificial respiration in respect of duration and pressure, prognosis of the individual patient, as well as a differential therapy, appear possible.
The variety of diseases and courses that may be povoqued by fungi in the lungs is consistent with an equal multitude of radiologically-morphologically visible alterations. Only a few of these radiological signs are characteristic with regard to differential diagnosis of the infection. As long as the pathogen has not been identified, a wide range of differential diagnoses must be considered which can only be restricted by careful overall view with all clinical findings. Nevertheless, detailed analysis of the often indistinct x-ray patterns is imperative in order to contribute to evaluating the course and therapy of aspergilloses.
The authors implanted balloon-expanded stents in the trachea of 10 rabbits for 1 day to 6 months. Follow-up included chest radiography, clinical examination, light microscopy, and scanning electron microscopy. Pneumothorax occurred in two cases after placement, marked stridor due to mucus plugging in all cases, signs of infection in three cases (two of which developed into pneumonitis), compression of the upper stent end in two cases, and moderate to severe mucus plugging in all cases. Microscopically, none of the stents was completely covered with epithelium even at 6 months. The high rate of complications may be a result of the rigid construction, which does not allow tracheal movement or adaptation of the stent shape to the shape of the trachea.
A prospective study of 85 patients with oral cancer, treated with high-dose radiation therapy, was performed to assess the value of magnetic resonance imaging (MRI) and scintigraphy for diagnosis of pathologic changes in the mandible. During postradiotherapeutic monitoring, radiation osteomyelitis occurred in 12 cases, tumor recurrences infiltrating the mandible in five cases, and progressive periodontal disease in nine cases. MRI permitted early diagnosis of radiation osteomyelitis in 11 out of 12 cases; only two cases were false positive. In scintigraphy with 99mTc-HDP, all alterations of the mandible, such as osteoradionecrosis, tumor infiltration, and periodontitis, showed a high uptake, resulting in a sensitivity of up to 100%, but a low specificity of 57%. Scintigraphy permitted assessment of the extension and location of the lesions. Both methods were superior to conventional radiography and clinical examination and should be integrated into a comprehensive follow-up program after radiation therapy.
PURPOSE: To assess the temporary Günther filter system concerning handling, complication rate and efficacy in respect to prophylaxis of pulmonary embolism. PATIENTS AND METHODS: 45 temporary Günther filters were placed in 44 patients (mean age 46 years) with deep venous thrombosis of the iliac and/or inferior vena cava. RESULTS: The mean time until filter retrieval was 6.1 +/- 4.1 days (maximum 14 days) dependent on the success of either thrombolytic therapy or thrombus consolidation. 27 patients underwent systemic thrombolytic therapy (61%), three patients (7%) received local thrombolysis. 14 patients (32%) were treated with heparin in a therapeutic dosage (PTT > 60 sec). We observed four complications (8.8%): one accidental arterial puncture (carotid artery on attempting an internal jugular vein approach), one infection located at the puncture site and one caval vein thrombosis in a patient with known heparin-associated thrombocytopenia. One patient died of pulmonary embolism despite correct filter positioning. CONCLUSION: Percutaneous placement of inferior vena cava filters is therefore an easy, safe and effective prophylaxis in respect of pulmonary embolism if combined with thrombolytic therapy or therapeutic heparinisation.
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Six cases of idiopathic fibrosis are presented to demonstrate the different manifestations of the disease and the efficiency of CT and MRI. In addition to the most common form, retroperitoneal fibrosis (Ormond's disease), fibrosis was seen in the mediastinum and pelvis. The inflammatory aortic aneurysm is a special variant. MRI was superior to CT in many diagnostic requirements. The extent of fibrosis was demonstrated more sensitively and MRI showed sclerosis in regions that appeared normal on CT. Occlusion of large vessels and collateral circulation were better depicted on MRI. The superior tissue contrast of MRI permitted differentiation of several stages of inflammation, which is of major significance for treatment and follow-up.
We inserted Gianturco-Z stents in 17 patients with tracheobronchial stenoses on 18 occasions. Three patients had benign, all others malignant stenoses due to compression of the tracheobronchial tree by metastasising malignancies. In all cases the stents could be easily positioned and the patients experienced relief of their severe dyspnea. In one case there was fatigue breakage of the stent. The patient was therefore given a silicone tracheal stent.
15 completely occluded iliac arteries (five cases over 10 cm, 8 cases between 5 and 10 cm and two cases below 5 cm) were reviewed for their interventional management, technical results and complications. The procedure was successful in 14 of 15 cases (93%). In six cases we performed local thrombolysis before PTA. In the patient group with "only PTA" the treatment had to be abandoned in one case because of the risk of embolism. Two patients suffered from a distal embolism of the same side and one patient from an ipsi- and contralateral embolism. A stent implantation was necessary in one patient. In the group of patients with prior local thrombolysis there was no complication nor was there an indication for a stent-implantation. Hence, we conclude that a primary local lysis with a consecutive PTA is an appropriate treatment of complete long occlusions of the iliac artery.
Hickman catheters are used mainly in patients with hematologic diseases, especially lymphatic and myelotic leukemias, and malignant lymphomas. They facilitate the administration of chemotherapeutics, hyperosmolar solutions and other substances with local toxicity as well as frequent taking of blood samples. Usually Hickman catheters are placed by surgical cut-down on a jugular vein. In lieu of this surgical placement, we recommend the implantation of Hickman catheters by means of interventional radiology techniques. In a period of 13 months 78 Hickman catheters were placed in 67 patients, 37 catheters (= 47%) stayed more than one month, 8 catheters (= 10%) stayed 5 to 8 months in the central venous system, 26, respectively 6, of these catheters are until now in situ. Lethal or life threatening complications did not occur. There were no infections at the introduction site of the catheter. The main complications were: pneumothorax without drainage: 3.2%, pneumothorax with drainage: 3.2%, slipping back of the tip of the catheter: 4.8%, thrombosis of the subclavian vein: 3.2%, fluid in the pleural cavity: 1.6%. In correspondence to the literature the complications of Hickman catheter placement by means of interventional radiology are less serious than by means of surgical cutdown. Further advantages are: general anesthesia can be avoided (less strain on severely ill patients, no problems to wean from assisted ventilation in patients with respiratory insufficiency), the smooth curve of the implanted catheter avoids sharp kinking and occlusion of the lumen, very small skin incisions are sufficient (lesser risk of hematomas in patients with thrombopenia), time and cost are reduced in comparison to surgical placement.
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32 patients with secondary Raynaud's syndrome and known basic disease (thromboangiitis obliterans, arterial sclerosis, collagenosis) were examined by high-resolution arterial subtraction angiography. There were typical organic fixed vessel irregularities in relation to the extent of the disease. In early stages, however, the functional vasospastic disorder dominates. The extent and the reversibility of the vasospasm were documented after pharmacological treatment. Pharmacoangiography of the hand can therefore be used as helpful method in the differential diagnosis and therapy of Raynaud's syndrome.
NiTi prostheses were perorally inserted in 12 rabbits. The spiral prostheses were overgrown by normal tracheal epithelium over time. No adverse effects due to impairment of the mucociliary clearance and no chondromalacia occurred. We conclude that perorally insertable prostheses made of the shape-memory alloy NiTi may be used as endotracheal or endobronchial prostheses.