Ultrasound-induced temperature increase in guinea-pig fetal brain in utero: third-trimester gestation.
Ultrasound Med Biol. 1998 Nov;24(9):1501-10. PMID: 10385971
Department of Veterinary Clinical Sciences, University of Sydney, NSW Australia.
Temperature increase was measured at various depths in the brain of living fetal guinea pigs during in utero exposure to unscanned pulsed ultrasound at ISPTA 2.8 W/cm2. Mean temperature increases of 4.9 degrees C close to parietal bone and 1.2 degrees C in the midbrain were recorded after 2-min exposures. When exposures were repeated on the same sites in each fetus after death, the corresponding mean temperature increases were 4.9 degrees C and 1.3 degrees C, respectively. Cerebral blood perfusion had little cooling effect on ultrasound-induced heating in the guinea pig fetus of 57-61 days gestational age.