No abstract available

[en] Depth and position of the parasternal lymph glands are determined by scintigraphy in 67 patients treated by radiotherapy for breast carcinoma. The average depth is found to be 28 mm, and the average position 27 mm laterally from the median line. However, the variation in individual patients as well as between differential patients is so great that individual measurements must be deemed essential for adequate radiotherapy, especially when electrons are used for treatment. (orig.)

[en] In a number of cases it is necessary to estimate the radiation dose to organs far away from the target volume of a patient receiving radiotherapy, e.g. the dose to the gonads or to the fetus of a pregnant patient, often called the peripheral dose. For an accurate calculation of the peripheral dose due to brachytherapy, the tissue scatter and absorption as a function of distance r, T(r) needs to be taken into account. Historically, T(r) data from measurements and Monte Carlo calculations have been fitted to various algorithms (Meisberger, van Kleffens, and others). These calculational methods are, however, inappropriate in the range of distances above 10 cm. In the present work, results of measurements and EGS calculations are reported to determine the dose at distances up to 60 cm from Cs-137, Ir-192 and Co-60 sources. The influence of the size of the phantom was investigated. Several mathematical models to fit the data were investigated. The model of Kornelsen and Young, T(r) = (1 + k_a.(μ.r)^kb).exp(-μ.r), proved to give the best fit to the results. Parameters for this model were derived for the three isotopes. The total reference air kerma (TRAK), which is the sum of the products of the reference air kerma rate of the sources of an implant and the duration of the application, can then be used: with a simple application of the inverse square law, neglecting effects from patient size and tissue inhomogeneities, a good approximation of the dose-in-patient in the range 10 cm < r < 60 cm is obtained from: D(r) = TRAK ^* (100/r)^2* T(r). A few experiments in a Rando Alderson phantom are presented to support the measurements and the calculations

[en] A survey is given of the radiation doses of personnel of the Dr. Bernard Verbeeten Institute for radiotherapy and nuclear medicine. The radiation exposure has been split up for groups of workers and for the kind of techniques or apparatuses. (R.B.). 1 ref.; 3 tabs

[en] An accurate estimate of the dose outside the target area is of utmost importance when pregnant patients have to undergo radiotherapy, something that occurs in every radiotherapy department once in a while. Such peripheral doses (PD) are also of interest for late effects risk estimations for doses to specific organs as well as estimations of dose to pacemakers. A software program, Peridose, is described to allow easy calculation of this peripheral dose. The calculation is based on data from many publications on peripheral dose measurements, including those by the author. Clinical measurements have shown that by using data averaged over many measurements and different machine types PDs can be estimated with an accuracy of ± 60% (2 standard deviations). The program allows easy and fairly accurate estimates of peripheral doses in patients. Further development to overcome some of the constraints and limitations is desirable. The use of average data is to be preferred if general applicability is to be maintained. (author)

[en] The rate of temperature changes was studied in a nylon thimble chamber provided with a temperature sensor, when the chamber was inserted in different phantom media. It was found, that the temperature time constant for the changes ranged from 40 s (chamber in water) to 515 s (chamber with build-up cap in air). It was also found, that handling the detector for about 30 s caused a temperature rise of about 1⁰C. This temperature rise was reflected in dose-rate measurements with a graphite ionization chamber, but was not measureable with a nylon chamber. (Auth.)

[en] An accurate estimate of the dose outside the target area is of utmost importance when pregnant patients have to undergo radiotherapy, something that occurs in every radiotherapy department once in a while. Such peripheral doses (PD) are also of interest for late effects risk estimations for doses to specific organs as well as estimations of dose to pacemakers. A software program, Peridose, is described to allow easy calculation of this peripheral dose. The calculation is based on data from many publications on peripheral dose measurements, including those by the author. Clinical measurements have shown that by using data averaged over many measurements and different machine types PDs can be estimated with an accuracy of ± 60% (2 standard deviations). The program allows easy and fairly accurate estimates of peripheral doses in patients. Further development to overcome some of the constraints and limitations is desirable. The use of average data is to be preferred if general applicability is to be maintained. (author)

[en] A detailed comparison of maintenance costs shows that a cobalt machine is much less expensive than a smaller linear accelerator, even if account is taken of an exchange of source every 5 years. (author). 4 refs.; 1 fig.; 1 tab

[en] A solution is presented for the problem of receiving and storing the excreta of patients to whom radioactive iodine has been administered for the treatment of hyperthyroidism or thyroid gland carcinoma. The solution was found by installing a chemical toilet with flushing facilities connected to receiving tanks via a shut-off valve. (orig.)

No abstract available