(1) Some infantile patients requested the attendance by the side treatment table even during radiation treatments. resulting in inevitable exposure of the attendant. In forty-two years, from 1925 to 1968,the attendants reached about 600 persons in the Chiba University Hospital. The gonadal exposure of the attentants was sometimes expected as considerable. This report is concerned with the direct measurements of gonadal exposure on the attendants of infantile patients. The measurements employed the regular pocket chamber placed at the external or the vaginal fornix. The dose measured with the chamber indicated 526 to 848 mR in total during the X-ray deep therapy, approximately equivalent to 50 mR in average per 100R exposure on the infantile patient.(2) X-ray deep therapy on the pituitary region had been adopted as the treatment of functional disturbances of the ovary including sterility. Such a radiation treatments have been given to about 4000 patients at the Department of Gynecology, Chiba University Hospital until the end of 1969. The number of patients treated was approximately corresponding with 40% of out-patients with functional disturbances of the orary including sterility. The ages of the patients ranged 15 to 50 years. and 70% of patients belonged to 20 to 29 years old. The measurement of gonad dose upon the patients, employing the regular pocket chamber, showed 40 mR in average, which was consistent with the results of the phantom experiment.
In recent years, multi-phase rectifying instruments have come to be widely used in tune with the popular use of continuous angiography and TV fluoroscopy techniques. However, the quality as well as quantity of X-rays emitted by the 6-pulse or 12-pulse rectifying instrument has not been fully elucidated as compared with that by the conventional, singlephase 2-pulse rectifying method. The following report is an attempt to such an analysis.(1) In experiment, no great qualitative difference was observed between the X-rays generated by the 2-pulse unit and those by the 12-pulse one, but in quantity the 12-pulse unit was capable of producing approximately 1.5 times as much X-rays as by the 2-pu1se unit.(2) In theory, by expounding Kulenkampff's experimental formula, comparison was made of the X-ray outputs obtained by different rectifying methods. Practically no qualitative difference was observed between the x-rays from the 6-pulse unit and those from the 12-pulse or constant potential unit, while a slight difference was seen between the X-rays from the 2-pulse unit and those from the 12-pulse or constant potential unit. With an inherent filter of 3mmAl, the quantity of X-rays from the 12-pulse or constant potential unit was 1.4-1.5 times of those from the 2-pulse one, while the X-rays from the 6-pulse one was 1.3-1.4 times in quantity of the 12-pulse one.(3) Our measurements show a good agreement with the absorption curve reported by the Radiation physics Laboratory in N. B. S., whereas Kulenkampff's calculations present only a slight attenuation, which proves a qualitative hardness of the X-rays produced.
Some clinical experiences and technological problems in using the pluridirectional tomographic unit are discussed and compared with that of ordinary linear tomographic unit. The unit used is Toshiba LGM-I. With this unit any one of various tube and film orbits for blurring out the shadows not in the tomographic plane can be chosen. They are linear, circular, spinal and hypocycloidal. Quality of the tomogram taken with this unit by linear movement is almost same as with ordinary unit, but in cases of the paranasal cavity, the internal auditory canal and the spinal column tomogram by complicated orbit are superior to that with ordinary unit. one of the technological problems taken place with this new unit is the positioning of the patient. The thickness of the tomographic layer of the complicated orbit is thinner than that of tha ordinary orbit, so that the most accurate positioning of the patient is required. New device for the positioning aid of the tomography of the head and neck region is presented.
By examining these registration cards installed at the Section of Public Health, Prefectural Government, it was learned that there are 354 hospitals and 3022 private offices of practitioner in Aichi Prefecture. In the hospitals 968 X-ray units are installed and in the private office of practitioner 1962. In the offices stood for radiology 11.7% of practitioners has X-ray units while nonradiologist are there. Practitioners for gastroenterology. internal medicine, surgery, obstetics gynecology, ophthalmology have the X-ray units with their percentage of 72.6,58.3,62.6,39.2,22.6 in this order. Enquete cards were delivered to the department of Radiology of 13 hospitals in Aichi Prefecture where radiologist were taking services. The exposure time of fluoroscopy conducted by nonradiologist was longer than that by radiologist.