The graft in 178 renal transplant patients was irradiated in an effort to halt acute rejection phenomena. Of the patients, 61 per cent received their transplant from either a sibling, parent or child and 38 per cent received cadaveric kidneys. Of the irradiated kidneys 61 per cent were functioning at 6 months, 58 per cent at 12 months and 49 per cent at 18 months. The rational for irradiation of transplanted kidneys with acute rejection is discussed.
In the treatment of Hodgkin’s disease according to KAPLAN (1966) the cervical, mediastinal, hilar and axillary nodes are irradiated. Although as much as possible of the lung tissue is protected from irradiation there is always a potential risk of pulmonary, mediastinal and myocardial injury. LARSSON et coll. (1976) have recently investigated the effect on the cardiovascular system. They found an increased incidence of ECG abnormalities, mainly T-wave changes and atrial arrhythmias, during treatment and also a considerable fall in the arterial blood pressure in about 20 per cent of the patients. However, 6 months after treatment the abnormalities had disappeared. The effect on the pulmonary gas exchange following irradiation of the mediastinal, hilar, cervical and axillary nodes is now reported.
Pretreatment staging laparotomy in carcinoma of the uterine cervix has been advocated because surgical staging may detect disease not apparent clinically. An analysis of survival and local control data from previously reported large series of patients with carcinoma of the uterine cervix shows that surgical staging does not increase survival rates. It is likely that surgical staging may also increase morbidity from therapy.
The xerographic technique has been introduced at Radiumhemmet for direct field control in therapy with high energy photon radiation (60Co-unit, 6 MV linear accelerator and 42 MeV betatron). The xerograms are of a sufficiently good quality for this purpose. The advantages and disadvantages connected with the xerographic facilities at present available are discussed.
The modulation transfer function of radiologic imaging systems is commonly obtained by determining the line spread function (LSF) of the system and computing its Fourier transform. Ideally, LSF should be obtained with infinitesimally narrow slits. The use of finite slits for obtaining the LSF is analyzed theoretically. An expression for the MTF of a finite rectangular slit is derived. Slit width correction of observed MTF is discussed as well as the correction for any generalized slit configuration.
Isotope nephrography was performed in 90 cases of carcinoma of the uterine cervix stage I B before radical hysterectomy with pelvic lymph node dissection. Ureteric involvement was indicated in 15 patients, 10 of these had metastases to the pelvic lymph nodes. The overall metastases detection rate was 55 per cent.
Some phantom measurements of absorbed doses from Norwegian dental radiography are presented. The mean bone-marrow dose from a single molar bite-wing projection was assessed to 1 mrad, a conventional full mouth examination (10 exposures) 7 mrad and an orthopantomographic exposure 2 mrad. The population dose from Norwegian dental radiography was estimated to be: mean bone-marrow dose 1 mrad and genetically significant dose 0.012 mrad.
A review of the morphologic, biochemical and clinical effects of hyperthermia on malignant cells indicates the presence of two principally different heat-induced alterations. (1) A 'destructive' lysosomal dependent cytoplasmic reaction dominates the tumour-cell devitalization in vivo, probably influenced by the characteristic tumour cell environment. (2) 'Repressive' nuclear abnormalities may be observed, but seem to be secondary in the in vivo reaction. However, under certain conditions (combined treatment modalities) this nuclear effect may be of importance.
A method capable of continuously recording the changes in the physiologic activity of ciliated cells during irradiation has been used to analyse the importance of photon energy for the early biologic effects of ionizing radiation. Gamma rays from 60Co and 50 kV roentgen rays were used. Important differences were demonstrated and conventional RBE values are not valid for early effects. The results are discussed and RBE for 50 kV roentgen rays has been calculated in respect to early effects of irradiation.
Frozen mouse cadavers were exposed to 220 kV roentgen irradiation with the thymic area covered with a lead plate sized 18 mm X 24 mm X 4 mm oe 18 mm X 12 mm X 4 mm. Lif-Telfon rods were used for dose measurements. With larger plate the mean dose from scattered radiation, in percent of that in the uprotected abdomen, was 12.77 (thymic lobes) and 18.34 (vertebra). With the smaller shield the figures were markedly increased, 16.70 and 23.77, respectively. Since the percentage dose is relatively high, the amount of scattered radiation may have biologic significance.
The frequency of recurrences in a material of 463 patients with mammary carcinoma following treatment by surgery with or without postoperative roentgen or cobalt irradiation to the operation area and regional lymph nodes is analysed. Postoperative irradiation to the operation area seems to prevent the chest wall recurrences even in stage I mammary carcinoma.
Absorption of glucose and sucrose by intestine from supralethally irradiated rats was investigated using an in vivo preparation. An activation of glucose absorption one day day after exposure is followed by a marked fall in glucose and sucrose absorption on day 3. Experiments under different conditions of loading indicate that at 20 hours active transport of glucose is already impaired although the maximum velocity is increased. After 3 days maximum velocity and active transport decrease markedly. Inverstase activity increases after 20 hours, but this is not accompanied by an increased sucrose absorption. The defect in sucrose absorption 72 hours after irradiation is paralleled by a decrease in invertase activity.
The influence of temperature on the early effects ionizing irradiation has been analysed using the trachea of the rabbit. ATP is assumed to be released by the effect of irradiation on the mitochondrial membranes, which increases the mucociliary activity in the epithelium, registered second-by-second during irradiation performed at 20 degrees C, 30 degrees C, 37 degrees C and 40 degrees C. The early effects of irradiation depended on the temperature, while hyperthermia does not potentiate this condition. A possible explanation is that phosphofructokinase, which is probably stimulated by irradiation, is inactivated at lower temperatures.
The first 22 MeV micron installation for radiation therapy is described with regard to the general design, the beam transport and the gantry. The first measurements of the electron depth dose curves indicate that the distributions obtained are superior to those of most betatrons and linear accelerators. For the same electron beam energy the depth of dose maximum and the 90 or 80 per cent dose level is considerably increased. The 20.9 MV photon beam has similar depth dose characteristics as a 20 MV betatron.
Early radiation effects on the physiologic activity of ciliated cells during exposure have been investigated at 0.34Gy/s and 0.05 Gy/s. The results obtained indicate a more intense early biologic effect at a higher dose rate. The mechanisms of radiation injury are discussed.
Twenty-two patients with Burkitt's lymphoma in complete remission induced by either cyclophosphamide or a combination of cyclophosphamide, oncovin and methotrexate were randomized to receive or not to receive prophylactic cerebrospinal irradiation. Six of 11 irradiated patients relapsed with tumour of the central nervous system as compared to 4 of 11 controls. Relapse frequency appeared to be related to stage of disease on admission. It is concluded that irradiation does not prevent relapse.
New Clambda-values (Cair,lambda) are proposed which should be applied for ionization chambers with an inner wall of air-equivalent material, air eq. plastic or graphite. The new values are up to approximately 3 per cent lower, and apply for a chamber with an inner wall lining of water-equivalent material.er cent higher than those published in the ICRU Report No. 14 and here named Cwater,lambda as the inner wall is considered water-equivalent. Also two sets of CE-values are proposed, namely Cair,E which is given in ICRU No. 21 and Cwater,E which is approximately 3 p
The relative central absorbed dose preceding and following air layers and channels in a polytetrafluorethylene (teflon) phantom has been measured with LiF-teflon dosimeters. Focus phantom distance is set to 100 cm and the field sizes range from 3 cm X 3 cm to 6 cm X 6 cm. Absorbed dose decrease and build-up factors in front of and behind the air cavity are evaluated. The build-up factor is strongly dependent on field size. Measurements of absorbed dose in water and polystyrene yield approximately the same results as in teflon if the linear dimensions of the irradiation geometry (including depth in phantom) in water and polystyrene are equal to 1.84 and 1.99 respectively times the corresponding parameter in teflon. The underlying transformation procedure is derived. The absorbed dose correction factors in the region behind the slab are discussed in terms of tissue-air-ratio and effective attenuation formulae.
Irradiation of human peripheral lymphocytes in vitro reduces their capacity to be triggered to DNA-synthesis by PHA in a two-dose shaped fashion suggesting the presence of one relatively radiation sensitive and one relatively resistant cell population. Intracavitary and external radiation therapy for carcinoma of the uterus and vagina, which reduced the lymphocyte counts by approximately 66 per cent, did not significantly change the ratio of these subpopulations, indicating that PHA-reactive cells cannot be grouped into radiation sensitive and resistant subpopulations.
