Choroidal binarization analysis: clinical application

Introduction: Image processing of optical coherence tomography scans through binarization techniques represent a non-invasive way to separately asses and measure choroidal components, in vivo. In this review, we systematically search the scientific literature regarding binarization studies published so far. Methods: A systematic research was conducted at PubMed database, including English literature articles for all of the following terms in various combinations: binarization, choroid/al, enhanced depth spectral domain/swept source optic coherence tomography, and latest publications up to November 2018 were reviewed. Results: Thirty-seven articles were included and analyzed regarding studied disease, binarization method, studied variables, and outcomes. Most of the studies have focused on the more common retinal pathologies, such as age-related macular degeneration, central serous chorioretinopathy and diabetic retinopathy but binarization techniques have also been applied to the study of choroidal characteristics in ocular inflammatory diseases, corneal dystrophies and in postsurgical follow-up. Advantages and disadvantages of binarization techniques are also discussed. Conclusion: Binarization of choroidal images seems to represent a promising approach to study choroid subcomponents in an increasingly detailed manner.