ABSTRACT
Microbeam radiation therapy (MRT) is a radiotherapy modality that uses arrays of highly collimated, quasi-parallel micrometer-sized X-ray beams to deliver high radiation doses (Bravin et al. 2015). Its inception dates back to the late 1950s when H. J. Curtis and C. P. Baker, Brookhaven National Laboratory (BNL), the United States, discovered that the threshold dose for normal tissue damage was several hundred Grays when irradiating a mouse brain with deuteron microbeams (Zeman et al. 1959, 1961). It was then found that the tolerance of normal tissue to radiation dose increases dramatically, which is inversely proportional to the size of the radiation field (Hopewell et al. 1987). This phenomenon is known as the dose–volume effect.
