1.Principle and safety of high power focused-beam microwave for deep heating
Jia LIU ; Wenhai ZENG ; Baifan ZHANG ; Chao GONG ; Zisheng HU ; Liping HUANG
Chinese Journal of Radiation Oncology 1992;0(01):-
ObjectiveTo evaluate the safety and effectiveness of high power focused-beam microwave for deep region/whole body heating.MethodsTen 20 cm?20 cm?2 cm Jiang Han-bao prescribtion muscle phantoms were counterpoised exactly to 37 ℃,then piled up under microwave applicator. Nine thermocouples were placed between the phantoms in the center to monitor the temperature during heating. The phantoms were heated with a series of different source-skin distances and powers with the temperature measured every 1-2 min. After heating,the thermal distributive images for the phantoms were attained by liquid crystal plate (LCP) with the temperature of 40-45 ℃. Five swines with 60-75 kg weight were heated 8 times (1-3 times for each swine ) for 120 min each session,with a heating power of 600-800 W. Serum and tissues including liver,kidney,colon-rectum,intestine,muscle,fat and lung were collected for pathologic examination before and after heating. ResultsThe temperature images of 2-10 cm depth attained immediately after heating by LCP showed that the aim temperature (equal or over 40 ℃) was achieved and exhibited uniform thermal distribution in these areas. The tissues of the swines showed no serious damage by either microscopic or electron-microscopic examination. Some serum enzymatic parameters temporarily increased after heating,then reduced to normal level after a short interval (about one week) ConclusionHigh power focused-beam microwave is effective and safe for deep region/whole body heating by either phantoms or animal tests.