Image Quality Assessment for Digital Volume Correlation-Based Optical Coherence Elastography

Abstract

Optical coherence elastography (OCE) based on digital volume correlation (DVC) has the advantages of full 3D displacements and strain tensor quantification. However, the measurement results are often unreliable due to the poor quality of the optical coherence tomography (OCT) speckle patterns. This paper proposes an image evaluation index based on OCT-DVC (CMGG, combined mean attenuation intensity, breadth and dispersion of the gray level distribution), which comprehensively considers the OCT signals’ attenuation and the breadth and dispersion of the gray level distribution of the OCT images. Virtual deformation experiments of phantoms by numerically applied displacements and deformation measurement of pork meat were conducted. The results of the mean bias errors have a corresponding good relationship with CMGG, which demonstrates the effectiveness of the proposed CMGG. Based on this index, a lot of time may be saved by a pretest evaluation during DVC-OCE measurement. CMGG also guides the development of OCE system design, adjustment and new DVC-OCE algorithms.

Keywords

• optical coherent elastography
• digital volume correlation
• displacement
• image evaluation index