Distribution mapping of ciliary beat frequencies of respiratory epithelium cells using image processing

Through their rapid periodic actions, the cilia of the human respiratory tract play an important role in clearing inhaled noxious particles. An automated method is developed, based on an image-processing technique, to measure and analyse objectively and quantitatively, ciliary beat frequency (CBF). Microscopic ciliary images are transformed into digitised grey images through an image grabber inside a PC, and signals are extracted from these, based on an image-subtraction algorithm, and are processed through power spectrum analysis using a fast Fourier transform (FFT). By means of the FFT power spectrum, maximum peak frequencies are detected as CBFs in each partitioned block for the entire digitised field. Using these CBFs, distribution maps are composed in various resolutions, showing visually the spatial distribution of CBFs through cells and in a single cell. To measure CBF variations quantitatively, phenylephrine hydrochloride is used, and the changes in CBF influenced by its concentration and duration are observed.