title: Comparison between diffuse infrared and acoustic transmission over the human skull.
abstract: Skull-induced distortion and attenuation present a challenge to both transcranial imaging and therapy. Whereas therapeutic procedures have been successful in offsetting aberration using from prior CTs, this approach impractical for imaging. In effort to provide a simplified means for aberration correction, we have been investigating the use of diffuse infrared light as an indicator of acoustic properties. Infrared wavelengths were specifically selected for tissue penetration; however this preliminary study was performed through bone alone via a transmission mode to facilitate comparison with acoustic measurements. The inner surface of a half human skull, cut along the sagittal midline, was illuminated using an infrared heat lamp and images of the outer surface were acquired with an IR-sensitive camera. A range of source angles were acquired and averaged to eliminate source bias. Acoustic measurement were likewise obtained over the surface with a source (1MHz, 12.7mm-diam) oriented parallel to the skull surface and hydrophone receiver (1mm PVDF). Preliminary results reveal a positive correlation between sound speed and optical intensity, whereas poor correlation is observed between acoustic amplitude and optical intensity.
authors.affiliation: Dept. of Biomedical Eng., Cleveland Clinic, Cleveland, OH.
authors.forename: Q
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Dept. of Biomedical Eng., Cleveland Clinic, Cleveland, OH.
authors.forename: N
authors.initials: N
authors.lastname: Reganti
authors.affiliation: Dept. of Biomedical Eng., Cleveland Clinic, Cleveland, OH.
authors.forename: Y
authors.initials: Y
authors.lastname: Yoshioka
authors.affiliation: Dept. of Biomedical Eng., Cleveland Clinic, Cleveland, OH.
authors.forename: M
authors.initials: M
authors.lastname: Howell
authors.affiliation: Dept. of Biomedical Eng., Cleveland Clinic, Cleveland, OH.
authors.forename: G T
authors.initials: GT
authors.lastname: Clement