Phase unwrapping for MHz optical coherence elastography and application to brain tumor tissue

During neuro-oncologic surgery, phase-sensitive optical coherence elastography (OCE) can be valuable for distinguishing between healthy and diseased tissue. However, the phase unwrapping process required to retrieve the original phase signal is a challenging and critical task. To address this issue, we demonstrate a one-dimensional unwrapping algorithm that recovers the phase signal from a 3.2x2005;MHz OCE system. With a processing time of approximately 0.11 s per frame on the GPU, multiple 2x03C0; wraps are detected and corrected. By utilizing this approach, exact and reproducible information on tissue deformation can be obtained with pixel accuracy over the entire acquisition time. Measurements of brain tumor-mimicking phantoms and human ex vivo brain tumor samples verified the algorithmx0027;s reliability. The tissue samples were subjected to a 200x2005;ms short air pulse. A correlation with histological findings confirmed the algorithmx0027;s dependability.