Allogeneic bone marrow transplantations were carried out between March 1983 and July 1985 in 31 patients aged 7 to 45 years (median 18 years). Acute lymphoblastic leukaemia in 1st to 5th remission was present in 8 patients, acute myeloblastic leukaemia in 1st and 2nd remission in 4 patients, chronic myeloid leukaemia, with various remission status, in 6 patients, 3 patients had severe aplastic anaemia and there were single cases of myelodysplasia and immature cell megakaryocytic myelosis. Transplantation was carried out during relapse in 8 patients with either acute myeloid or lymphoblastic leukaemia. Phenotypic HLA-identical mothers (n = 2) as well as genotypic HLA-identical siblings (n = 27), and in two cases HLA-non-identical mothers, served as bone marrow donors. In leukaemia patients the conditioning treatment consisted of fractionated total body irradiation and high dose cyclophosphamide or etoposide. Patients with severe aplastic anaemia received cyclophosphamide (4 X 50 mg/kg) and fractionated total nodal irradiation (total dose 8 Gy). 19 patients (61%) survived 14 to 605 days after bone marrow transplantation. 15 patients (48%) continue to remain in complete remission with Karnofsky indices of greater than or equal to 90%. Causes for death were infection (n = 3), interstitial pneumonia (n = 3), relapse (n = 3) as well as single cases involving acute graft-versus-host-disease, non-engraftment of donor marrow and veno-occlusive disease of the liver.

At the University of Kiel, myeloid and acute lymphatic leukemia is treated since 1983 by total-body irradiation applied prior to bone marrow transplantation. Dose deviations in the midplane caused by the irregular surface and tissue inhomogeneities of the patient are reduced down to +/- 3.5% compared to the central ray, with the help of CT-based individual compensators. This method prevents above all an excessive dose to the lungs. The radiobiologic advantages of fractionated irradiation have been employed for all patients treated hitherto (n = 9). At present, a total body dose of 12 Gy in six fractions is applied within three days. There were no undesired acute radiogenic reactions except a mild acute mucositis found in all patients. Chronic side effects, especially in the lungs, were not demonstrated, too. However, the average follow-up time of 149 days has been rather short. One patient died from relapse of leukemia after a total dose of 10 Gy, another patient died because the transplanted bone marrow was rejected, and a third died from catheter sepsis. Six out of nine patients are in complete remission with a maximum index of Karnofsky. The limited experiences gained hitherto show that the homogenous accelerated-fractionated total-body irradiation offers essential advantages compared to non-compensated single dose irradiation with respect to the prevention of undesired radiogenic effects in sound tissues and that its therapeutic efficacy is at least the same.

Fast neutrons are necessary for neutron radiography of extended biological objects. Applying cellulose nitrate foils to assure specific neutrograms undisturbed by X- and γ -ray effects, a multifoil stack can be used as detector in order to improve image quality and to reduce neutron dose down to less than 10 rem. Neutron radiography enables to observe the exsiccation process in biological materials, e.g. wood, which could not be achieved by X-ray radiography. In medicine neutron radiography could be of value for detecting pathological changes within bone such as replacement of bone marrow by fat or tumor, as shown in human vertebral columns.

Fast neutrons show sufficient penetration to test thick hydrogen containing objects. Neutron radiography can be done by track etch foil methods, which detects recoil nuclei especially protons. The imaging process has been studied in respect to optimal etching conditions, sensitivity and dose-density relations. A multifoil imaging system is proposed, which allows to lower the necessary neutron dose, supresses artifacts and expands the attainable density range. With this system a good sharpness can be achieved; this has also been shown by comparison of the modulation transfer function with those of different x-ray imaging systems.

The image recording of fast neutron radiographs can be achieved sufficiently by means of plastic foils and the track etching technique. The optimal etching conditions for cellulose nitrate foils were studied. A mathematical model for the dependence of the optical density on the area and number of the etch pits is given and compared to measurements. Finally, two examples of radiographic applications may underline the possible importance of this method.

Fifty cases with malignant tumors of the hypopharynx having been irradiated with cobalt-60 at the Radiological Clinic of the Kiel University between 1965 and 1979 are reported. The cumulative 10-year survival rate amounted to 16%. Age and sex, the histology and mode of growth as well as the stage (mostly III or IV) and the primary site of the tumor had no prognostic significance, whereas the tumor response to treatment proved decisive to the prognosis: of the cases clinically revealing complete regression of the tumor, 32% could finally be regarded as cured. Using sole radiation therapy it was possible to obtain total regression of the tumor in 72% with doses between 1500 and 1650 ret, and in 84% with doses between 1651 and 1800 ret. All the patients with clinically incomplete tumor regression deceased within a year.

The jet phenomenon seen during entry of urine into the bladder is illustrated by the urograms of a number of patients. Its diagnostic significance is discussed. Experimental models and theoretical considerations have shown that the jet is determined by the kinetic impulse; for a 1:10 mixture of contrastmedium and water, the jet is visible at all jet diameters and jet speeds at the orifice provided flow at the centre of the jet has fallen to about 0.073 m/s. Transferring these findings to man, and bearing in mind the functional and anatomical peculiarities and pressure differences between the lower ureter and the bladder, it becomes apparent that this phenomen can be produced under physiological conditions.