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Direct Blood Flow Measurements in a Free RPE-Choroid Graft with Phase-Resolved Doppler OCT.

ABSTRACT: We directly demonstrated the revascularization in a free retinal pigment epithelium (RPE)-choroid graft with direct blood flow detection by experimental phase-resolved Doppler optical coherence tomography (PRD-OCT).Seven patients with age-related macular degeneration underwent an RPE-choroid graft translocation in a prospective institutional cohort study. Spectral domain optical coherence tomography (SD-OCT) was used to measure the revascularization stage. With PRD-OCT the presence of flow was imaged postoperatively.The PRD-OCT confirmed flow in three patients when SD-OCT indicated the afferent vessel ingrowth stage, and in all seven patients when the SD-OCT indicated the efferent vessel ingrowth stage.The PRD-OCT study was able to detect the presence of blood flow in a free RPE-choroid graft. The PRD-OCT findings directly confirmed the revascularization that was otherwise based on the more circumstantial evidence provided by SD-OCT images and angiography.The use of both techniques to monitor the revascularization process in a free graft in patients are an interesting example of replacing more invasive by noninvasive techniques. There is potential future use of PRD-OCT for the visualization of vascularization patterns in other pathologies.

SUBMITTER: van Zeeburg EJ

PROVIDER: S-EPMC4294068 | biostudies-other | 2015 Jan

REPOSITORIES: biostudies-other

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Fractional Flow Reserve/Instantaneous Wave-Free Ratio Discordance in Angiographically Intermediate Coronary Stenoses: An Analysis Using Doppler-Derived Coronary Flow Measurements.

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