Eye Abnormalities in Mouse Fetuses Caused by Simultaneous Irradiaition of X-Rays and Ultrasound. 1. The Effects of Ultrasound on the Teratogenicity of X-Ray Irradiation

Abstract

The teratogenic effects of simultaneous irradiation of x-rays and ultrasound were studied, chiefly with regard to developmental eye abnormalities. On day 7 of pregnancy ddN mice were irradiated with 150 R of x-rays (30 R/min) and/or ultrasound at 1.5 or 3 W/cm^2 (1 MHz) for 5 min. All mice were killed on day 18 of pregnancy and the offspring were examined. Fetal mortality in each group irradiated with ultrasound at 1.5 or 3 W/cm^2 did not significantly differ from in the control groups. There was no significant difference between the two groups irradiated with ultrasound. The incidence of gross malformations was very low in each group irradiated with ultrasound at 1.5 or 3 W/cm^2 (0.8% in the former and 1.3% in the latter). These results indicated no detectable teratogenic effects of ultra-sound in the present experimental conditions. In the group simultaneously irradiated with x-rays and ultrasound at 3 W/cm^2, fetal mortality was significantly higher than in the other groups, but it did not differ between the group irradiated with x-rays alone and the group simultaneously irradiated with x-rays and ultrasound at 1.5 W/cm^2. The incidence of gross malformations did not differ among the three groups. The type and degree of malformations including eye abnormalities also did not differ with the group. These results indicated that the embarrassedly effects of x-rays in mouse fetuses were enhanced by simultaneous irradiation of ultrasound, but the teratogenic effects of x-rays were not enhanced in the present experimental conditions.