Optical coherence elastography (OCE) provides deformation or the material property mapping of soft tissue.1,2 The addition of elastographic contrast may improve the inherent ability of optical coherence tomography (OCT) to differentiate the composition and structure of soft tissue.3 Moreover, the mechanical information extracted from OCE is important for analysis and identification of pathological changes in soft tissue. For example, OCE may provide high-resolution characterization of strains in arterial walls, which would be important complementary information for determining the stability of atherosclerotic lesions.4 There are two main categories of OCE techniques, phase-based methods5,6 and speckle tracking techniques,7–9 which rely on the structure of the speckle pattern when it is fixed. In general, speckle-tracking based OCE can measure greater deformation than phase-based OCE methods as phase-based OCE is limited by the phase stability of OCT system10 and the phase wrapping induced by large physical deformations or high detected particle velocities within the imaging volume. Although phase unwrapping could extend the measurement range of the phase-based method, it is difficult to apply due to noise corruption or discontinuity of the wrapped phase maps in OCT imaging.6,11 The principle of speckle tracking techniques has been previously described by Schmitt.1 Briefly, the speckle can be temporally tracked by quantifying the displacement via cross correlation of the OCT images of prestressed and stressed tissue samples. However, the resolution for the displacement calculation was limited to 1 pixel and no strain elastograms were given, as the process of strain calculation by differentiating the displacements was very sensitive to noise. Kirkpatrick et al.12 demonstrated that a maximum likelihood speckle shift estimator is superior than cross correlation, when the tissue motion between frames is less than 0.8 pixels. However, in practice, it is difficult to estimate the pixel shift a priori. Moreover, if the deformation values have a wide range from subpixels to pixels, the maximum likelihood will not be effective. Another drawback of the existing speckle tracking methods is the use of numerical differentiation of displacements to obtain strains. This procedure is noise sensitive as any error in the displacement measurement will be amplified in its strain calculation.13 Due to these complications, the large majority of the present speckle-tracking based OCE techniques has not been verified for their measurement accuracy. Therefore, more advanced algorithms are required to improve the measurement resolution and accuracy. We aim to develop a robust speckle-tracking based OCE methodology with subpixel resolution and improved strain measurement accuracy.