Fig. 1

Ultrasound images of sea turtle eyes. A Examination of a Caretta caretta eye. B Chelonia mydas eye—coloured lines show the axial globe length (a), corneal thickness (b), anterior chamber depth (c), lens axial length (d), vitreous chamber depth (e). C Caretta caretta eye—slightly oblique image from which scleral ossicle width and thickness were measured (between arrows). D Eretmochelys imbricata eye showing oval shape with central optic axis (line) smaller than the equatorial diameter (dashed line), indicating the posterior shading of the orbit bone (asterisk). E Lepidochelys olivacea eye—note that despite the posterior ossicle artefacts, visualization of the posterior portions is not impeded. F Caretta caretta eye in power Doppler mode showing segments of blood vessels (in yellow–orange) distributed in the scleral cartilage. G Part of the salt gland (between arrows) adjacent to the bulb (*) of Lepidochelys olivacea. H Caretta caretta eye in power Doppler mode showing a large blood vessel (*) adjacent to the salt gland (between arrows), where few and small vessels were identified (arrow head)