title: Thermal dosimetry of spinal cord heating in the mouse.
abstract: Three systems for the localized heating of the spinal cord of the mouse have been evaluated by measuring the temperatures in the spinal canal (Tsp); at a reference location dorsal to the spine (Tdo), and by numerically calculating temperature distributions throughout two-dimensional transverse cross-sections through the middle of the heated region. The systems assessed were water bath heating alone, water bath-rf combination and rf heating alone with oblique, dorsally located electrodes. It has been established that (1) for all systems delta T (where delta T = Tdo-Tsp) decreased throughout a 1 h heating period-this was attributed to changes in blood flow; (2) there existed a considerable variation in the experimental value of delta T, particularly for rf heating. The resulting error in the estimation of Tsp from a measured value of Tdo can be reduced by making use of the observed correlation between delta T and the slope of a temperature decay curve measured at the beginning of the heating period; (3) rf alone best spares adjacent visceral and superficial tissues from significant elevation of temperature.
authors.affiliation: Department of Medical Physics, Manitoba Cancer Treatment and Research Foundation, Winnipeg, Canada.
authors.forename: G
authors.initials: G
authors.lastname: Froese
authors.forename: P B
authors.initials: PB
authors.lastname: Dunscombe
authors.forename: R M
authors.initials: RM
authors.lastname: Das
authors.forename: J
authors.initials: J
authors.lastname: McLellan
mesh_terms: D000818:Animals; D001831:Body Temperature; D005069:Evaluation Studies as Topic; D006358:Hot Temperature / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D011846:Radio Waves / Q000009:adverse effects; D012039:Regional Blood Flow; D013116:Spinal Cord / Q000098:blood supply; D013119:Spinal Cord Injuries / Q000209:etiology; D013821:Thermometers