Spatially mapping of tracheal ciliary beat frequency using real time phase resolved Doppler spectrally encoded interferometric microscopy (Conference Presentation)

Abstract

Ciliary motion in the upper airway is the primary mechanism by which the body transports foreign particulate out of the respiratory system in order to maintain proper respiratory function. The ciliary beating frequency (CBF) is often disrupted with the onset of disease as well as other conditions, such as changes in temperature or in response to drug administration. Current imaging of ciliary motion relies on microscopy and high speed cameras, which cannot be easily adapted to in-vivo imaging. M-mode optical coherence tomography (OCT) imaging is capable of visualization of ciliary activity, and phase-resolved Doppler (PRD) algorithm can be integrated to measure the ciliary beating direction and amplitude with nanometer sensitivity. However, since ciliary activity naturally happens on the tissue surface, enface imaging modalities should be more suitable than cross-sectional ones such as OCT. We report on the development of a spectrally encoded interferometric microscopy (SEIM) system using a phase-resolved Doppler (PRD) algorithm to measure and map the ciliary beating frequency within an en face region. This novel high speed, high resolution system allows for visualization of both temporal and spatial ciliary motion patterns with nanometer sensitivity. Rabbit tracheal CBF ranging from 9 to 13 Hz have been observed under different temperature conditions, and the effects of using lidocaine and albuterol have also been measured. This study is the stepping stone to in-vivo studies and the translation of imaging spatial CBF in clinics.