Imaging of the calf vocal fold with high-frequency ultrasound.
OBJECTIVE
High-frequency ultrasound imaging offers the potential for assisting in the diagnosis and treatment of vocal fold pathology if it allows aspects of vocal fold microstructure to be visualized noninvasively. The objective of this study was to assess the ability of high-frequency ultrasound to image vocal fold anatomy and injected biomaterials.


METHODS
The vocal folds of two excised calf larynges were imaged ex vivo and compared with corresponding histological sections.


METHODS
High-frequency ultrasound imaging was performed under saline submersion using 40 and 50 MHz transducers, and corresponding cryostat cross-sections were stained with H&E, Trichome, and Verhoeff's Van Gieson stains.


RESULTS
The epithelial surface, lamina propria, and underlying muscle were easily identified with the high-frequency ultrasound as verified with histological sections representing each imaged region. The arytenoid cartilage vocal process can also be clearly distinguished from the surrounding tissue, as can the full extent of injected biomaterials within the superficial lamina propria. Useful ultrasound resolution was obtained to depths of at least 10 mm within the tissue with the 40 MHz transducer.


CONCLUSIONS
This preliminary study demonstrates the capability of high-frequency ultrasound to image the layered anatomy of the calf vocal fold and to discern materials injected into the superficial lamina propria, indicating that this technology holds a strong potential for use in phonosurgery.
Walsh
Conor J
CJ
Department of Mechanical Engineering, Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, USA.
Heaton
James T
JT
Kobler
James B
JB
Szabo
Thomas L
TL
Zeitels
Steven M
SM
D000273:Adipose Tissue; D000818:Animals; D002417:Cattle; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D066298:In Vitro Techniques; D007267:Injections; D014463:Ultrasonography; D014827:Vocal Cords / Q000000981:diagnostic imaging*
D020136:Hydrogel, Polyethylene Glycol Dimethacrylate