a-scan ultrasonography

English Thesaurus

1. the use of ultrasonography to measure the length of the eyeball (noun.act)

hypernym	:	echography, sonography, ultrasonography, ultrasound,
definition	:	using the reflections of high-frequency sound waves to construct an image of a body organ (a sonogram); commonly used to observe fetal growth or study bodily organs (noun.act)