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Biomedical subjects

B Kasal

Publications and source records attributed to B Kasal.

5 recordsLinked to original sources
PubMed1988

131I dose to the human fetal thyroid in the Zagreb district, Yugoslavia, from the Chernobyl accident.

The 131I activity was measured in 30 human fetal thyroids in Zagreb district after the Chernobyl accident. A model of radioiodine metabolism in the mother and human fetus which takes into account the age dependence of the uptake and retention of radioiodine in the fetal thyroid was developed. Having assessed that the total intake by the average mother was about 1330 Bq, a good correlation between calculated and measured fetal thyroid activities was found (r = 0.77, P less than 0.001). The fetal thyroid dose reached the maximum of 0.43 micro Gy/Bq intake at about the fifth month of gestation. It was concluded that the risk of having a child with a harmful trait due to 131I absorbed by the mother was negligible.

Accidents↗
PubMed1983

Relationship between objective and subjective assessment of gamma camera image sharpness.

In order to relate the performance of the human observer to the objective specifications of a gamma camera system, images of a test object were taken under various conditions that could be expected to cause changes in resolution. Observers were asked to put the images in the order of increasing/decreasing sharpness. For the same physical conditions, objective measurements were made from which the resolution parameters FWHM and FWTM could be derived. By looking for significant differences in ordering of the images, it was possible to show that, within the limitations of the specific system investigated, a fractional change in FWHM of about 10% caused a significant change in image quality. Further experiments to test the universality of this figure are suggested.

Humans↗
PubMed1981

Dynamic mode LSF measurements for the scintillation camera.

A method is presented to improve the measurements of line spread function (LSF) of gamma cameras that makes use of a digital computer and a moving line source of radioactivity. Data acquisition is done in the dynamic mode with the computer, while the source moves across the collimator face. The resulting LSFs are defined with many curve points that enable very precise calculation of the corresponding modulation transfer function (MTF). The method is easily used in routine checking of gamma cameras. It makes possible a quick and precise determination of LSF for any point in the field of view of the detector.

Methods↗