Biomedical subjects
Publications and source records attributed to J Kollath.
We report on our initial results of 19 intraarterial digital subtraction angiographies in 18 patients. We saw diagnostic angiograms in all examinations. There were no complications. We conclude that the fine needle approach offers the possibility of outpatient angiography in selected cases.
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Percutaneous aspiration-thromboembolectomy is a simple method for removal of thrombo-embolic material of diverse origin. It is highly effective with small material outlay. As a third angioplasty method it has considerably improved the success rates of balloon dilatation and local lysis treatment with urokinase or streptokinase. The procedure was used alone or in combination on 71 occasions involving 69 limbs in 66 patients. An angiographically demonstrable success was seen in 96% and clinical improvement in 91.6%. Local lysis treatment with streptokinase or urokinase was shortened, less hazardous and, because of removal of non-lysable material, more successful. Embolectomy with the Fogarty catheter remains the method of choice for treating emboli arising from the heart in vessels of the aorto-iliac system. For smaller vessels below the inguinal ligament, however, we consider the new, lesser invasive method to be an alternative to vessel surgery.
In pediatrics angiography is a method that is used relatively rarely. During the last few years the introduction of nonionic contrast media has led to considerable progress in the field of conventional angiography since these contrast media are tolerated much better than the ionic ones. Also in the field of catheter techniques the introduction of new catheters has led to considerable progress. The new catheters are characterized by very thin walls and wide lumina which allow a high flow of contrast media. Their use in children has considerably reduced local complications at the puncture site. The introduction of digital subtraction techniques on the one hand made intravenous angiography in pediatric patients possible and on the other hand led to considerable reduction of contrast media as compared to conventional angiography. Motion artifacts, however, cause problems. In interventional radiology, as far as blood vessels are concerned, technical possibilities are the same for children as for adults. Dilatations of blood vessels are the main indications. For embolizations the indications are mainly tumor embolizations and bleeding embolizations.
We report the results and indications of 106 digital subtraction angiographies in 84 pediatric patients up to 16 years of age. 70 of the intravenous and all of the 21 intraarterial studies revealed diagnostic results and no further vascular study for the demonstration of the pathologic conditions was necessary.
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The influence of iodine concentrations and different volumes of a conventional ionic contrast media and a contrast media with low osmolarity on the quality of the results of intra-arterial digital subtraction angiography of the lower extremities in patients who underwent percutaneous transluminal angioplasty (n = 52) are reported. According to our results, intra-arterial injections of a conventional ionic contrast medium diluted with 0.9% sodium chloride solution, resulting in an iodine concentration of 190 mg/ml injectable solution, reveals the best results when injected in an amount of 6 ml per injection. The use of low-osmolarity contrast-medium showed no advantages, the quality of the resulting pictures was inferior to that revealed with the ionic compound. Probably this is because the iodine concentration in the diluted low-osmolarity compound was less.
The authors report on 18 patients with stenoses of the aortic isthmus in whom digital subtraction angiography had been carried out. In three patients DSA yielded the primary diagnosis of a postductal stenosis of the aortic isthmus. In all postoperative patients, restenosis of the aorta could either be excluded or confirmed. In three cases with complications after an operation, DSA supplied diagnostic information which was decisive for proceeding further. According to the authors' experience, intravenous DSA can replace conventional angiography in the majority of postoperative controls and in future also in primary diagnosis.
We report on the results of a comparison of intravenous and intraarterial digital subtraction angiography (iv and ia-DSA) with conventional angiography in patients with known renal masses. Whereas more than 80% of the tumours were diagnosed via IV-DSA, none of the benign renal cysts were identified. The overall detection rate, therefore, is 65% in all patients (n = 21) of the study group. The value of ia-DSA as a time sparing procedure, saving film-cost and contrastmedia, is discussed. The diagnostic accuracy of selective renal angiograms in digital and conventional technique yields equal results in our comparative study.
Treatment of esophageal stenosis by large diameter balloon catheters offers significant advantages over bouginage. Catheter dilating force is confined to the affected segment and can be controlled by the patient's reaction. Perforation is practically excluded by the use of fluoroscopy, contrast media, flexible angiographic guidewires, and better control over the time and forces of dilation. Wider, more lasting dilation can be achieved. Forty-one dilations were done on 21 patients with this new procedure without complications and with improved relapse-free intervals.
Subtraction angiocardiography (DSAK) with a fully digitalised system (DR 960) provides a well defined demonstration of the left ventricle after peripheral venous contrast injection. Cardiac volume and ejection fractions were calculated by a dedicated software programme and the findings correlated with cine ventriculography (CA) (r = 0.91), biplane echo cardiography (2 DE) (r = 0.77) and radionucleid ventriculography (RNV) (r = 0.85); the method can be used even with reduced cardiac output (EF less than or equal to 15%). Densitometric measurements of the EF on phantoms correspond with morphometric findings, but its clinical application is at present not possible because of the frequent appearance of artefacts. Analysis of regional disturbances of ventricular wall movements shows very good correlation between DSAK and CA and these appear more accurate than 2 DE. DSAK is a valuable, rapid and reproducible method with few side effects for cardiological diagnosis.
The new imaging method digital subtraction angiography (DSA) permits intravenous arteriography. 1259 patients were thus investigated over one year. The lower extremities comprised 21,4% of assessment areas. 120 investigations in 95 patients were based on an indication of percutaneous transluminal angioplasty (PTA). DSA can be used before and after the PTA. The small extent of invasiveness and the shortening of in-patient admission are particular advantages preoperatively. These advantages, in addition to the possibility of out-patient evaluation, are also true for DSA in comparison to the conventional arteriography. Thus the combination of both methods has been found to be very suitable.
Intravenous digital subtraction pulmonary angiography was performed in 220 patients. Of these, 206 had suspected pulmonary embolism. Our intravenous studies yielded images of diagnostic quality in 98% of cases. Compared to conventional pulmonary angiography, intravenous digital subtraction angiography (IV DSA) is safer, faster, and easier to perform. This technique is an acceptable substitute for routine pulmonary angiography in all patients with pulmonary embolism. Intravenous DSA is currently the procedure of choice for the evaluation of patients with suspected pulmonary embolism.
The typical signs of the rupture of the thoracic aorta in the chest radiographs of patients with this injury are shown. Because all these signs lack specificity only angiography was diagnostic till now. Digital subtraction angiography (dsa) as a new diagnostic procedure can replace invasive angiography. In four cases the rupture of the aorta was clearly diagnosed by means of digital subtraction angiography. In three additional cases it could be definitely excluded.
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Explore the source record for details and available documents.