Fast Optical Coherence Elastography via Optimized Sampling Density With Preserved Accuracy

Optical coherence elastography (OCE) is a non-invasive imaging technique for quantifying tissue stiffness. The spatial resolution of elastography maps is closely related to the spatial sampling density required to adequately represent mechanical features. In this study, we investigated the effect of spatial sampling density on OCE by varying the number of effective sampling points along scanning axes using the proposed phase-gradient velocity estimation method. These methods were validated using agar phantoms and in vivo human facial acne and the results showed that down sampling reduced computational cost by around 69% and up to about 89%. For the down sampling results of the acne dataset, the velocity changed by only 5.82% in an affected lesion. These results provide a practical criterion for reducing acquisition and post-processing time while establishing the quantitative relationship between spatial sampling, elastography accuracy and computational efficiency.