Biomedical subjects
Publications and source records attributed to M V Helzel.
CT-Sonogram as an independent examination should be used in defined cases of ileus combined with pregnancy, obesity, great abdominal tumours (e.g. large hernias). Less x-ray exposure and absence of faulty x-ray films are the arguments in favour of this method.
Differences in the inflow pattern between the right and left renal vein seen in bolus contrast medium application can simulate vena cava thrombosis.
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A quantitative comparison of changes in renal size after the intravenous injection of contrast media showed no difference between ionic and non-ionic contrast medium. Contrast media of similar osmolarity (Metrizamide and Ioxaglate with 470 and 490 mosn/kg H2O) did show significant variations. Evidently properties of the contrast medium, other that their osmotic behaviour, are of significance (chemical structure, viscosity, iodine content, specific toxicity, and the effect on the permeability of biological membranes, calcium-binding activity, effect on coagulation). Changes in renal size could be reproduced by repeating the contrast injection at 24 to 48 hours.
Sonographic evaluation of the width of the spinal canal is inferior compared to CT or myelography, concerning accuracy and especially quantity of information received. The advantage of sonography is the lacking of X-ray exposure, the non-invasive procedure and the low cost of apparatus and operational time. For these reasons sonography is favoured as a screening method in detecting spinal canal stenosis in a group whose handicap was largely occupational or sport-related.
Sonography, combined with a geometrical simulation-model, can be used to estimate parameters of pulmonary function tests (PFT). The sensitivity for changes of PFT may be increased by repetitive examinations. This simple inexpensive method is easily reproducible. Additional information concerning diaphragmatic motility is obtained. The value of this method is improved by taking geometric parameters directly from chest radiograph using a suitable computer program.
The sonographic imaging of the vena lumbalis ascendens dextra is demonstrated; the possibility of sonographic imaging of the vena lumbalis ascendens sinistra and parts of the great lymphatic vessels (ductus thoracicus, trunci lumbales, cysterna chyli) is outlined for the first time.
First experiences with contrast media, so-called "sonographica", for the purpose to improve the ultrasonographic diagnostic of the upper abdomen are reported; special emulsions and suspensions with particle diameters between 50-2000 mu were used. The sonographica cause an echo texture similar to the liver and a more homogeneous ultrasonic absorption in the upper abdomen--within the range of frequencies and intensities used in sonographic diagnostic. This improves the possibility of obtaining cross-sections by using several transducers--arranged on a circuit--simultaneously. By increasing the echogenicity of the sonographicum the thickness of the stomach and duodenal wall can be indicated regularly for the first time.
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Explore the source record for details and available documents.