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Imaging of the Vascular Distribution of the Outer Ear Using Optical Coherence Tomography Angiography for Highly Accurate Positioning of a Hearable Sensor

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Journal APL Bioeng
Date 2024 May 27
PMID 38799376
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Abstract

Novel hearable technology is securely and comfortably positioned within the ear canal minimizing inaccuracies caused by accessory movements during activities. Despite extensive research on hearable technologies within the outer ear, there is a lack of research in the field of vascular imaging and quantitative analysis in the outer ear , which is one of the crucial factors to select the appropriate sensor position. Therefore, in this paper, we introduced optical coherence tomography angiography (OCTA)-based qualitative and quantitative analyses to visualize the inner vasculature of the outer ear to acquire vascular maps for microvascular assessments . By generating maximum amplitude projection images from three-dimensional blood vascular volume, we identified variations of blood vessel signal caused by the different biological characteristics and curvature of the ear among individuals. The performance of micro-vascular mapping using the proposed method was validated through the comparison and analysis of individual vascular parameters using extracted 20 vascular-related variables. In addition, we extracted pulsatile blood flow signals, demonstrating its potential to provide photoplethysmographic signals and ear blood maps simultaneously. Therefore, our proposed OCTA-based method for ear vascular mapping successfully provides quantitative information about ear vasculature, which is potentially used for determining the position of system-on-chip sensors for health monitoring in hearable devices.

References
1.
Mase M, Micarelli A, Strapazzon G . Hearables: New Perspectives and Pitfalls of In-Ear Devices for Physiological Monitoring. A Scoping Review. Front Physiol. 2020; 11:568886. PMC: 7596679. DOI: 10.3389/fphys.2020.568886. View

2.
Dabiri B, Kampusch S, Geyer S, Le V, Weninger W, Szeles J . High-Resolution Episcopic Imaging for Visualization of Dermal Arteries and Nerves of the Auricular Cymba Conchae in Humans. Front Neuroanat. 2020; 14:22. PMC: 7236887. DOI: 10.3389/fnana.2020.00022. View

3.
Kim Y, Jung G, Jeon D, Wijesinghe R, Seong D, Lee J . Non-Invasive Optical Coherence Tomography Data-Based Quantitative Algorithm for the Assessment of Residual Adhesive on Bracket-Removed Dental Surface. Sensors (Basel). 2021; 21(14). PMC: 8309505. DOI: 10.3390/s21144670. View

4.
Tatham A, Medeiros F . Detecting Structural Progression in Glaucoma with Optical Coherence Tomography. Ophthalmology. 2017; 124(12S):S57-S65. PMC: 6882427. DOI: 10.1016/j.ophtha.2017.07.015. View

5.
Ekelem C, Yu J, Heydarlou D, Heidari E, Csuka E, Chen Z . The effect of melanin on in vivo optical coherence tomography of the skin in a multiethnic cohort. Lasers Surg Med. 2019; 51(5):407-411. DOI: 10.1002/lsm.23086. View