Correlation mapping method for generating microcirculation morphology from optical coherence tomography (OCT) intensity images

Abstract

Standard optical coherence tomography (OCT) in combination with software tools can be harnessed to generate vascular maps in vivo. In this study we have successfully combined a software algorithm based on correlation statistic to reveal microcirculation morphology on OCT intensity images of a mouse brain in vivo captured trans-cranially and through a cranial window. We were able to estimate vessel geometry at bifurcation as well as along vessel segments down-to mean diameters of about 24 μm. Our technique has potential applications in cardiovascular-related parameter measurements such as volumetric flow as well as in assessing vascular density of normal and diseased tissue.

Minimizing projection artifacts for accurate presentation of choroidal neovascularization in OCT micro-angiography

“…From the scanning protocol of OCT micro-angiography, we analyze the changes in both magnitudes (speckle pattern) and phases among four repeated B-scans. In doing so, hereby we choose intensity decorrelation [22] due to its normalization operation, which reduces the influence of intensity values when evaluating the difference, and phase variance [23] to denote the changes in magnitude and phase among repeated B-scan measurements. The same transversal location as shown in Fig.…”

“…This fact implies that it would be difficult for all the current OCTA algorithms to directly differentiate the projection artifacts from the true blood vessel signals. These algorithms include, but are not limited to, complex OCT signal based approach, such as OMAG [24,25]; magnitude based approach, such as decorrelation [22], SSADA [26] and speckle variance [27]; and phase based approach, e.g. phase variance [23].…”

Noninvasive structural and microvascular anatomy of oral mucosae using handheld optical coherence tomography

“…Additionally, various OCT-based angiography techniques have been intensively developed including Doppler/Doppler-variance OCT [33,34], optical micro-angiography [35,36], speckle-variance OCT (sv-OCT) [37,38], and correlation-mapping OCT (cm-OCT) [39,40]. In particular, the OCT intensity-based angiographic methods include sv-OCT and cm-OCT, which estimate the intensity variance or cross-correlation between time-variant Bscans obtained at the same location.…”

Circumferential optical coherence tomography angiography imaging of the swine esophagus using a micromotor balloon catheter

“…OCTA was later performed using motion contrast, by calculating the amplitude, phase, or complex amplitude variation of the OCT signals between neighboring B-scan frames [27]. Amplitude-based OCTA relaxes system phase stability requirements and has good sensitivity to slow blood flows in the capillaries [28][29][30][31][32]. In addition, the majority of microvasculature is oriented transverse to the OCT beam, and thus it is difficult to visualize with Doppler OCT because of the small axial phase shift from the Doppler effect.…”