FIELD: medicine; medical engineering. SUBSTANCE: method involves injecting boron- and/or gadolinium-containing substance in prolonged action medicinal form into a biological object 5 min before exposure to radiation. The biological object is irradiated with heat neutron beam of 20-150 mm diameter and 5•108-109 th/cm2•s tn/γ with background gamma-radiation power in the beam being not greater than 0.14 R/s during 15-60 min. The device has horizontal channel with graphite scattering unit positioned tangentionally to the active zone of the water-type nuclear reactor and closed with aperture of 10 to 150 mm diameter at its exit to working chamber. System for producing neutron beam has five gate rings with conic collimator unit mounted into three central rings having divergence angle α=1.8-2.0 deg and manufactured from high pressure polyethylene which density ρ = 0.97 g/g/cm3. Filter from polycrystalline bismuth with density ρ=9.75 g/g/cm3 is mounted in the third gate ring when moving in the beam propagation direction which ratio l to distance to diaphragm L is l/L=1/(30-40). Lead and polyethylene bushings are placed in the first gate ring. Biological protection of the operation chamber has movable unit connected with desk which surface has steps coupled with steps on the internal surface of the operation chamber. Stationary biological protection of the operation chamber is built from steel carcasses filled layer-by-layer with 5-6 mm thick layer of lead and boronized polyethylene. Two frames are mounted on the desk in parallel to each other. The first of which has fixing members in front of the aperture for fixing biological object or head phantom. The second frame has tuning concentric rings spaced over polymethyl metacrylate plate attached to the frame for directing neutron beam and mounting dosimetric detectors. EFFECT: high therapeutic effectiveness. 2 cl, 6 dwg
