Application of acoustic microscopy to the study of embryonic development

Abstract

A preliminary investigation was conducted to determine the acoustically revealed details of embryonic tissue. A fixed, but unstained 72-hour chick embryo specimen was imaged at an acoustic frequency of 100 MHz with the scanning laser acoustic microscope [L.W. Kessler, P.R. Palermo, and A. Korpel, Nature 232, 110 (1971)]. The acoustic micrographs obtained, which exhibited a resolution of 20 μm, revealed many organ formations and regions of cell condensation within the embryo. In order to minimize the alterations to the tissue structures, histological staining techniques were not employed. Consequently, the optical opacity of the specimen precluded our obtaining a useful optical image for comparative purposes. This paper will discuss the comparison between the structures revealed in the acoustic microscope and the established microanatomy of the embryo. It will also be shown that the selective interaction of sound with the different tissue structures in the embryo may be considered to be analogous to a hypothetical new staining technique.