An individual professionally trained to perform diagnostic evaluations of the eye and its diseases, including examinations for ophthalmic foreign bodies, tumors, radiation injuries, inflammatory diseases, and vascular lesions as well as measurements of axial length (e.g., in cataract surgeries and intraocular lens implantation). In the U.S., professionally trained ophthalmic sonographers are certified in their specialty by the American Registry of Diagnostic Medical Sonographers.