Evaluation of Biological Effect of Ultrasound in Albino Rat Fetuses in Late Gestation Age

Abstract

This is an In-vivo Experimental (randomized control) study which involves ultrasound wave exposure to pregnant Albino Rat uterus, at late gestation period, to evaluate the bioeffects of ultrasound in fetuses at late gestation age. Specific objective of this study are to evaluate bio effect of ultrasound as a teratogen in form of intrauterine growth restriction, and see possibility of histology change brain tissue from ultrasound exposure . The study was conducted at National University –Sudan Radiology Lab from May 2015 to December 2017 using temporary constructed Animal House which follow international guidelines of animal house care with constant external environment and daily monitoring by animal house technician. Ultrasound machine was calibrated and exposure parameter were fixed as linear array transducer of 12MHz, focal distance was 4.5 cm ,Thermal Index was .5 Mechanical Index was .8 ,duration of exposure was 40 minute. Pregnant albino rats were grouped to exposed and control, and were sacrificed in the next days of exposure (17, 18, 19, 20, 21) then fetuses were taken out for evaluation of effect, the sample obtained was 55 fetuses. Calibrated weigh scale was used to measure fetal weigh by veterinary specialist, slide brain histopathology done by a specialized technologist and was reported by veterinary histopathologist. XI Regarding intrauterine growth , there is reduction in fetal weight through determined study days but more significant at day 19 of rat gestation day P-value < .005.Multiple histological brain change was observed in different groups, shown as loss of normal pattern formations . It is concluded that ultrasound exposure to fetal may act as deleterious bio effect in Albino Rat and this may act as same in human subject as some previous studies. This study needs to be replicated with extension and modification of parameters and using large animal model to mimic humans ALARA (As Low As Reasonable Achievable) principle is important concept to be adopted by ultrasound medical professional in their practice with update to consensus report from upcoming research that may reveal ultrasound bio effect to humans, especially offspring.