Experimental assessment of the impact of high acoustic power ultrasound diagnostics on animal eyes

Abstract

Purpose: to study the impact of diagnostic ultrasound of high acoustic power on animal eye tissues in the experiment.Material and methods. 46 Chinchilla rabbits (92 eyes) were divided into the main group of 38 rabbits (76 eyes) and the control group of 8 rabbits (16 intact eyes). Animals of the main group were exposed for 30 minutes, through closed eyes, to high-intensity ultrasound (MI 0.9–1.0, TI 1.5–2.0, Ispta.3 50 mW/cm2) by colour Doppler imaging and pulsed Doppler. All animals of this group had corneal thickness measured by optical coherence tomography (OCT) before and immediately after exposure to ultrasound (20 rabbits) and also 2 weeks later (18 rabbits). During the same time span, the content of heat shock proteins HSP27 (HSPB1), HSP60 (HSPD1) and inflammatory mediators: monocytic chemotactic protein-1 (MCP-1), interleukin-6 (IL-6) and interleukin-8 (IL-8) in blood serum and vitreous was determined. Histopathological examinations of the enucleated eyes of rabbits with morphological and morphometric assessment of retinal tissues were performed on the 1st day and 2 weeks after exposure to ultrasound.Results. Immediately after ultrasound exposure and 2 weeks later OCT data reflected no structural changes in the cornea. Quantitative assessment of the levels of HSPD1, HSPB1, MCP-1, IL-6 and IL-8 in blood serum and vitreous did not reveal statistically significant changes after ultrasound exposure. A morphological study including an assessment of morphometric characteristics revealed the absence of apoptotic changes in the layers of the retina at different times after exposure to high-intensity ultrasound.Conclusions. We established no immediate or delayed bioeffects of high acoustic power diagnostic ultrasound exposure lasting up to 30 minutes on the biological media and ocular tissues of animals.