High-Speed Holographic Shape and Full-Field Displacement Measurements of the Tympanic Membrane in Normal and Experimentally Simulated Pathological Ears

Abstract

To improve the understanding of the middle-ear hearing mechanism and assist in the diagnosis of middle-ear diseases, we are developing a high-speed digital holographic (HDH) system to measure the shape and acoustically-induced transient displacements of the tympanic membrane (TM). In this paper, we performed measurements on cadaveric human ears with simulated common middle-ear pathologies. The frequency response function (FRF) of the normalized displacement by the stimulus (sound pressure) at each measured pixel point of the entire TM surface was calculated and the complex modal indicator function (CMIF) of the middle-ear system based on FRFs of the entire TM surface motions was used to differentiate different middle-ear pathologies. We also observed changes in the TM shape and the surface motion pattern before and after various middle-ear manipulations. The observations of distinguishable TM shapes and motion patterns in both time and frequency domains between normal and experimentally simulated pathological ears support the development of a quantitative clinical holography-based apparatus for diagnosing middle-ear pathologies.

Mammalian middle ear mechanics: A review

“…The motion of the tympanic membrane in response to sound has been studied using various measurement techniques, including capacitive probes ( Von Békesy, 1941 ; Von Békésy, 1960 ), laser doppler velocimetry (LDV) ( Schops et al, 1987 ; Stasche et al, 1994 ; Goode et al, 1996 ; Aarnisalo et al, 2009 ; Szymanski et al, 2009 ; Aarnisalo et al, 2010 ; Kunimoto et al, 2014 ; Wang et al, 2016 ; Jiang et al, 2019 ), speckle contrast interferometry ( Lokberg et al, 1980 ; Wada et al, 2002 ), holography ( Tonndorf and Khanna, 1970 ; Tonndorf et al, 1971 ; Tonndorf and Khanna, 1971 ; Furlong et al, 2009 ; Rosowski et al, 2009 ; Cheng et al, 2010 ; Cheng et al, 2013 ; Khaleghi et al, 2013 ; Dobrev et al, 2014 ; Khaleghi et al, 2015a ; Khaleghi et al, 2015b ; Tang et al, 2019 ; Tang et al, 2021 ), and optical coherence tomography (OCT) ( Subhash et al, 2012 ; Chang et al, 2013 ; Burkhardt et al, 2014 ; Dobrev et al, 2016 ; Park et al, 2016 ; Razavi et al, 2016 ; Jeon et al, 2019a ; Jeon et al, 2019b ). More details about the methods are reported in the appendix.…”

Numerical model characterization of the sound transmission mechanism in the tympanic membrane from a high-speed digital holographic experiment in transient regime

“…HDH allows to measure TM movements produced by a short impulse (click) fast enough to ignore movement artifacts associated with physiological noise such as movements associated with breathing, heart beating, etc. The transient response captured by the high-speed camera (>50k frames per second) allows the analysis of TM impulse responses [ 18 ], in both normal and experimentally simulated pathological human middle ears [ 19 ]. Recently, Tang et al, [ 20 ] used the HDH to record human cadaveric TM transient responses induced by acoustic impulses.…”

Two-wavelength interferometry for measurement of transonic airflow in a compressor blade cascade

“…Interferometry is one of the basic tools in the field of flow visualization. Digital interferometric methods using sensitive high-speed cameras [3] make it possible to quantify the quantities of airflow fields with high accuracy and spatial resolution. Interferometric techniques are based on "encoding" the optical phase of a wave to a measurable intensity in the form of interference fringes.…”