Ultrasound--a research tool in the study of accommodation.

Measurements of the globe were made at different stages of accommodation with Kretz A-mode ultrasonic equipment. A comparison between the movement of the crystalline lens in two refractive groups appeared to show that the highly myopic lens had to expand more per dioptre of accommodation; in other words, it was less efficient than the near-emmetropic lens. Also the posterior surface of the lens appeared to move more in highly myopic eyes than in near-emmetropic eyes.