High-frequency ex vivo ultrasound imaging of the auditory system.
A 50MHz array-based imaging system was used to obtain high-resolution images of the ear and auditory system. This previously described custom built imaging system (Brown et al. 2004a, 2004b; Brown and Lockwood 2005) is capable of 50 microm axial resolution, and lateral resolution varying from 80 microm to 130 microm over a 5.12 mm scan depth. The imaging system is based on a 2mm diameter, seven-element equal-area annular array, and a digital beamformer that uses high-speed field programmable gate arrays (FPGAs). The images produced by this system have shown far superior depth of field compared with commercially available single-element systems. Ex vivo, three-dimensional (3-D) images were obtained of human cadaveric tissues including the ossicles (stapes, incus, malleus) and the tympanic membrane. In addition, two-dimensional (2-D) images were obtained of an intact cochlea by imaging through the round window membrane. The basilar membrane inside the cochlea could clearly be visualized. These images demonstrate that high-frequency ultrasound imaging of the middle and inner ear can provide valuable diagnostic information using minimally invasive techniques that could potentially be implemented in vivo.
Brown
Jeremy A
JA
Dalhousie University, Halifax Nova Scotia, Canada B3H 1V7. J.Brown@dal.ca
Torbatian
Zahra
Z
Adamson
Robert B
RB
Van Wijhe
Rene
R
Pennings
Ronald J
RJ
Lockwood
Geoffrey R
GR
Bance
Manohar L
ML
D003051:Cochlea / Q000000981:diagnostic imaging; D004423:Ear / Q000000981:diagnostic imaging*; D004429:Ear Ossicles / Q000000981:diagnostic imaging; D004432:Ear, Middle / Q000000981:diagnostic imaging; D005240:Feasibility Studies; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D014057:Tomography, X-Ray Computed; D014159:Transducers; D014432:Tympanic Membrane / Q000000981:diagnostic imaging; D014463:Ultrasonography