Cochlear Soft Tissue Imaging Using In-Line Phase Contrast

Abstract

Problem Most contemporary imaging methods require invasive specimen preparation and/or are time consuming, or lack sufficient spatial resolution. Methods Experiments were made at the Advanced Photon Source (APS), Argonne National Laboratory. The APS is a synchrotron radiation source of the third generation, for which the particular characteristic is the highly coherent X-ray radiation. X-rays are generated with an undulator, inserted in a straight section of the storage ring. Images taken with hard X-rays and the grating interferometer were compared with images from the same specimen acquired with light microscopy. Results The results show that imaging of cochlear soft tissue structures is possible with hard X-rays and a grating interferometer. Conclusion Imaging of cochlear soft tissue structures is possible with hard X-rays and a grating interferometer. Significance It is important to examine cochlear morphology from many points of view, including comparative anatomy, cochlear developmental changes, malformation caused by genetic defects, changes related to diseases, sensory physiology, and cochlear modeling. Best imaging results were obtained from in situ experiments in the absence of tissue distortion. However, most contemporary imaging methods require invasive specimen preparation and/or are time consuming, or lack sufficient spatial resolution. A method that potentially overcomes these shortcomings is presented in this paper and it uses hard X-rays and a grating interferometer. Furthermore, hard X-rays would allow imaging cochlear soft tissue structures without opening the cochlea itself. Support The UNICAT facility at the Advanced Photon Source is supported by the U.S. DOE under Award No. DEFG02-91ER45439, through the Frederick Seitz Materials Research Laboratory at the University of Illinois at Urbana-Champaign, the ORNL (U.S. DOE contract DE-AC.