Correlation-stability approach to elasticity mapping in OCT: comparison with displacement-based mapping and \textit{in vivo} demonstrations

TL;DR

This paper introduces a correlation-stability method for elasticity mapping in OCT that outperforms traditional displacement-based approaches in noise tolerance and operational range, demonstrated through simulations and in vivo tests.

Contribution

It proposes a novel correlation-stability approach for elastography in OCT, offering wider operational strain range and better noise tolerance compared to conventional displacement-based methods.

Findings

CS approach has a wider operability region in strain

CS method is more tolerant to noise

Demonstrated effectiveness with simulated and in vivo images

Abstract

A variant of compression optical coherence elastography for mapping relative tissue stiffness is reported. Unlike conventionally discussed displacement-based (DB) elastorgaphy, in which the decrease in the cross-correlation is a negative factor causing errors in mapping displacement and strain fields, we propose to intentionally use the difference in the correlation stability (CS) for deformed tissue regions with different stiffness. We compare the parameter ranges (in terms of noise-to-signal ratio and strain) in which the conventional DB- and CS-approaches are operable. It is shown that the CS approach has such advantages as significantly wider operability region in terms of strain and is more tolerant to noises. This is favorable for freehand implementation of this approach. Examples of simulated and real CS-based elastographic OCT images are given.