Igaku butsuri : Nihon Igaku Butsuri Gakkai kikanshi = Japanese journal of medical physics : an official journal of Japan Society of Medical Physics最新文献

In 1982, the Osaka General Medical Center made a modernization plan and started construction of a new hospital. The new radiology department was studied from the layout of the rooms to the newly introduced equipment and data storage system. Just around that time (1983), Fuji Computed Radiography (FCR) was developed.Using this FCR, we took on the challenge of the world's first full digitalization of a general radiography system.At that time, we took the following policies to improve the system.(1) To digitize all general radiography.(2) To review the radiography process, improve the equipment, and build a system to link the equipment together.(3) Change the selection of radiography equipment to one that is compatible with the digital system (small focus: magnified radiography).(4) Convert all ideas, including image processing, to digital systems.These attempts were successful and became the basis for the current field of general radiography.

Clinical studies of boron neutron capture therapy (BNCT) have been conducted using thermal and epithermal neutron beams generated from research reactors. Considering the spread and development of BNCT, it has been desired to realize BNCT using an accelerator-based neutron source that can be installed in medical institutions. To date, the accelerator-based BNCT has been developed by combining various accelerators such as a cyclotron and a linear accelerator with neutron generation targets. In Japan, the world's first treatment system using a combination of a cyclotron and a beryllium target has received manufacturing and marketing approval as a medical device. In June 2020, BNCT insurance medical treatment was started at medical institutions. Currently, BNCT is being performed for cases of locally unresectable recurrent or unresectable advanced head and neck cancer. In this paper, it is shown that the history of reactor-based BNCT and the current development status and future prospects of the accelerator-based BNCT, which has been carried out in advance in Japan.

A calibration service using a medical accelerator has been launched to calibrate a radiotherapy dosimeter in terms of an absorbed dose to water. The radiotherapy dosimeter calibrated by the calibration service can measure the absorbed dose to water without a beam quality conversion factor. In this paper, an overview of the calibration service for a high-energy photon beam and a high-energy electron beam was described, as well as methods of absorbed dose measurement and cross-calibration using the calibrated radiotherapy dosimeter. And the development status of a dose standard for a particle beam was reported.

Exposure to ionizing radiation (IR) increases the risk of cancers, as epidemiology studies of atomic bomb survivors and patients who have received radiotherapy show. The carcinogenic effects of IR are well-documented, although the effects of radiation carcinogenesis change in each organ. The mammary gland is known to be highly susceptible to radiation-induced cancer. We have previously reported that (i) differential DNA methylation patterns in rat mammary carcinomas induced by pre-and post-pubertal IR; (ii) the effect of parity on rat mammary carcinogenesis varies between pre-and post-pubertal IR. In this review, we summarize our radiation researches as well as related with other radiation researches in rodent models.

A number of epidemiological studies have been conducted to investigate the health effects of low-dose radiation. The author reviewed epidemiological studies among radiologists, radiological technologists, and nuclear workers. Because the results of many epidemiological studies on these subjects have been published, and many studies have measured radiation doses, there is little uncertainty. In the studies among radiologists and radiological technologists, high risks for leukemia, skin cancer, and breast cancer were found in populations that began work before around 1950, but not seen such a tendency for those starting work recent years. The results of the studies among nuclear workers were inconsistent with some reporting that a risk was seen, while others reported no risk. The reason for this may be due to the different analysis methods among the studies.

This is a review article on luminescence in water published by JSRT and JSMP (https://www.jsmp.org/en).abe.