Quantifying tympanic membrane dynamics in otitis media using low coherence interferometry

Low coherence interferometry (LCI);Tympanic membrane mobility;Otitis media

Won, Jungeun ; Boppart ; Stephen A.

关键词: Low coherence interferometry (LCI);    Tympanic membrane mobility;    Otitis media;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/99414/WON-THESIS-2017.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Examining middle ear dynamics and mobility of the tympanic membrane (TM) is essential when diagnosing otitis media (OM), or a middle ear infection. OM is a widespread infectious disease in childhood, characterized by the accumulation of middle ear fluid, known as middle ear effusion (MEE). Loss of TM mobility assessed by pneumatic otoscopy may help in determining the presence of a MEE, but its qualitative information has challenged its proper application. In order to provide more efficient and quantitative analysis of the TM dynamics, a pneumatic low-coherence interferometry (LCI) otoscope was developed with automated pressure generation.The pneumatic LCI system developed during this research measures the TM displacement with an axial resolution of around 6.5 μm, and provides simultaneous pressure measurement in the ear canal with a temporal resolution of 1 msec. To facilitate the analysis, two quantitative metrics (compliance and amplitude ratio) were defined to compute the pneumatic mobility of the TM and the middle ear pressure (MEP). Followed by phantom studies and human subject testing, a total of 42 ear datasets from pneumatic LCI system and tympanometry were acquired from 30 pediatric outpatient subjects at Carle Foundation Hospital (Urbana, IL) to assess the clinical significance in relation to OM. As a result, the compliance and the amplitude ratio in the ears with OM were statistically lower than those in the normal group, showing the capability of the pneumatic LCI metrics to represent the TM mobility and characterize different middle ear conditions. The comparisons with current middle ear diagnostic devices, such as otoscopy and tympanometry, are discussed with the limitations of the study, and future directions for the research are presented in the conclusion. Overall, this thesis demonstrates the potential of non-invasive optical sensing and imaging methods to quantitatively describe the changes in middle ear dynamics experienced during OM.