Biomedical subjects

K Vyska

Publications and source records attributed to K Vyska.

At least 55 records · Page 3Linked to original sources

PubMed1977

[Isotope angiographic measurement of blood flow velocity in the human aorta and major arteries. I. Methodology and physiological considerations].

A special 8-channel detector arrangement was used to determine atraumatically the mean blood flow velocities in the aorta and the large arteries of the lower extremities in man. Following intravenous injection of 99mTc-pertechnetate time-activity curves were recorded over defined measuring points over the arteries, from these the appearance times of the tracer determined, and the mean blood flow velocities calculated from the differences between appearance times (the minimal transit times) and the distances between measuring points. The simultaneous determination of the minimal transit times between the vena cava inferior and the root of the aorta, which correspond closely to the total cardiac transit times, permits recognition of cases in whom blood flow velocity is reduced as a result of cardiac disease.

Adult↗

PubMed1976

[Isotope studies of cerebral circulation using the Fucks-Knipping gamma camera: use of a multi-parameter system with an intravenous tracer injection technic].

In order to analyze cerebral blood flow for diagnostic purposes, Indium 113m-DTPA was i.v. injected into seated patients, and time-activity curves were registered by a multifacet gamma camera (Fucks-Knipping) from 8 regions of interest, from the median area and from the right and left side of the head: 3 from the hemisphere, 3 from the brain stem, 2 from the large arteries of the neck. The results from 14 patients with chronic impairment of cerebral blood flow were compared with normal data from 20 healthy individuals. The time activity curves were analyzed for peak-height, mean transit time, and ratio peak to plateau height. The individual parameters were investigated for the degree of their correlation in a multiparameter system. The results from the patients indicated for the different single parameters a non-uniform response. There was also no correlation between the deviation of different parameters, between single pathological parameters and the degree and the site of blood flow impairment. On the other hand, a positive correlation was found between the number of pathological parameters and the degree of blood flow impairment irrespective of the site of its localization. Reason for this result probably is the variable location and degree of blood flow compensation by collaterals, which predominantly are expected at the cerebral base. The data indicate the potential usefulness of the application of the multiparameter analysis to quantitatively detect the degree of impairment of cerebral blood flow without regard to its topography. In this respect, the method, here described, promises to be of clinical value for non-invasive and non-hazardous diagnostic screening of cerebral blood flow.

Adult↗

PubMed1976

[Analysis of DNA histograms by computer (author's transl)].

INTRODUCTION: Quantitative DNA cytophotometry, the study of morphology of chromosomes and cell kinetics are important approaches toward characterization of genetic information. Each approach has its own problems and limits. Difficulties with interpretation of DNA histograms arise from a lack of proper terminology, and from attempting to interpret them in terms of the existing terminologies for chromosomal analysis and cell kinetics. Aim of this research was to develop a computerized mathematical analysis of DNA histograms. MATERIALS AND METHODS: As a basis for the comparison of normal with those of tumor cell populations the DNA histograms of heart muscle cells were selected for the normal cell population from 14 normal hearts of adults, 16 hypertrophic hearts, 14 non-polyploidized hearts of children, and 14 hypertrophic hearts of children with congenital malformations. Normal diploid cell populations from 7 effusions were also included. The 24 populations of malignant cells consisted of primary tumors and metastatic effusions. DNA cytophotometry was performed on single nuclei in Feulgen stained preparations by means of the UMSP/XD 50 ZEISS. The approximation of the DNA histograms by linear combination of normal distributions was done according to spline-function and calculated by means of the IBM-375. RESULTS: The nuclear classes 2C, 4C, and 8C show no differences between the normal, left and right heart with respect to mean values (X), standard deviations (sx), variances (sX) and coefficients of variance (sx/X). However, coefficients of variance are smaller in hypertrophic (2.15 to 8.37%) than in normal hearts of adults (8.90 to 10.85%), and larger in hypertrophic heart of children (4.06 to 7.09%). The mean values of the DNA classes 2C, 4C, 8C, and 16C vary witin +/- 18.6% with a probability of 95.5%. Benign effusions contain only 2C and 4C nuclei with a variance of 4.00% and 8.75%, respectively. In DNA histograms of malignant cells, only one third has a first peak outside of 2C +/- 18.6%. In approximately one fifth of the histrograms the position of the second or third peaks deviates significantly from normal polyploid values. Since a large proportion of polyploid nuclei is limited to only a few normal tissues, pronounced polyploidy is suggestive of malignancy in all other tissues. If in the cases containing only two DNA classes, 2C and 4C, the populations are malignant, the proportion of 4C is more than 8% while in the corresponding benign populations the proportion of 4C atains only 2.97 +/- 2.5%. In some cases a few highly polyploidized nuclei not taken into a account by our computer program are suggestive of malignancy. In only one DNA histogram out of the 24 analysed, all of these criteria are negative. In six cases the computer analyses reveal two stemlines of tumor cells with corresponding polyploid values.

Adult↗

PubMed1976

[Minimal cardiac transit times in the diagnosis of heart disease: measurements with the gamma retina V and indium-113m. The influence on central volume relationships of long-term digitalis therapy in patients with latent and manifest coronary insufficiency].

Using Indium-113m and the Gamma Retina V (Fucks-Knipping Camera), the minimal cardiac transit times (MTTs) were measured radiocardiographically from the right auricle to the aortic root. This analysis served to determine the relation between stroke volume and the segment volume of the part of circulation between the right auricle and the aortic root. In 39 patients with myocardial insufficiency of different clinical degree the effectiveness of digitalization was, up to a period of 5 years, measured by means of the volume relation mentioned above. The following conclusions can be drawn from the results: digitalization of patients with myocardial insufficiency leads to an improvement of the impaired relation of central volumes. In patients with diminished cardiac reserve the improvement is drastic and often results in a nearly complete normalization. The data remain constant during therapy even for an observation period of 5 years. Digitalization of patients with congestive heart failure only leads to a partial improvement. In contrast to patients with diminished cardiac reserve this effect is temporary. The different behaviour of the relation between stroke volume and segment volume in patients with diminished cardiac reserve and congestive heart failure under prolonged administration of digitalis points to the necessity of treatment with digitalis in the early stage of myocardial disease.

Adult↗

PubMed1975

[Isotope-angiographic measurement of aortic flow velocity for differential diagnosis of aortic sclerosis].

The speed of flow between aortic arch and abdominal aorta was determined from the corresponding minimal transit time (MTT) measured with 113m-In-DTPA and the Fucks-Knipping gamma camera. A total of 144 individuals was examined: 62 normal persons, 34 patients with cardiac insufficiency; 31 patients with hyperkinetic syndrome (effort syndrome and hyperthyroidism) and 17 patients with isolated aortic sclerosis without impairment of cardiac function. In all individual groups there was a highly significant correlation between speed of flow and heart rate. For a given heart rate speed of flow was diminished in cases of cardiac insufficiency and aortic sclerosis; it was accelerated in patients with hyperkinetic syndrome. By plotting the speed of flow through the aorta, normalized to an arbitary heart rate, against the corresponding MTT, also normalized to the same heart rate, the presence of aortic sclerosis could be differentially recognized in 14 of the 17 patients with this disease.

Angiography↗

PubMed1975

[Minimal cardiac transit time in thyroid disorders and in the effort syndrome].

Minimal transit times (MTTs) were determined with the Fucks-Knipping gamma camera from differences between arrival times in consecutive cardiac compartments of blood radioactively labelled with 113m-In-DTPA Measurements were made on 50 patients with effort syndrome, 59 patients with hyperthyroidism before and after thyroid suppression therapy partly suffering from associated heart disease, and 25 patients with hypothyroidism before and after therapy with thyroid hormone. In patients with effort syndrome and hyperthyroidism, MTTs were often, but not always shortened below the control values; consequently, in case of associated heart disease, MTT-prolongation may be masked in such instances where hyperthyroidism causes MTT shortening. Hypothyroidism caused MTTs to be prolonged. The prolonged MTTs reverted to normal values upon adequate therapy with thyroid hormone.

Adult↗

PubMed1975