Novel Insight into Morphological Features and Vascular Profile of Selected Macular Dystrophies Using Swept-Source Optical Coherence Tomography and Optical Coherence Tomography Angiography

Abstract

Our perception of macular dystrophies has evolved overtime from collective grouping into hereditary disorders of unclear etiology and no effective treatment to avid search for the underlying pathogenic mechanism that would provide base for future therapy. A causal conjunction between abnormalities in the photoreceptors layer and the RPE-Bruch's membrane complex and abnormal profile of the retinal vascular plexuses and the choriocapillaris-stands out as a plausible theory of pathogenesis. The recently introduced swept-source optical coherence tomography (SS-OCT) technology incorporates long-wavelength (1050-nm) scanning light, less susceptibility to sensitivity roll-off, and ultrahigh-speed image acquisition. These features enabled in vivo noninvasive visualization of different strata of the outer retina and the choriocapillaris with unprecedented finesse. Furthermore, the SS-OCT technology incorporated a blood flow detection algorithm; OCTARA that in tandem with the deeper penetration and superior axial resolution of SS-OCT enabled detailed assessment of the retinal capillary plexuses and the choriocapillaris in terms of structure and density. This novel technology could help explore yet undiscovered frontiers in the pathophysiology of macular dystrophies and guide future therapeutic approaches. This chapter includes a review of literature along with the authors' experience in imaging selected macular dystrophies using SS-OCT and SS-OCT angiography (SS-OCTA).

Customized Slab-Segmentation Method for Projection-Artifact Elimination in Best Vitelliform Macular Dystrophy: A Swept-Source Optical Coherence Tomography Angiography Study

“… 5 Consequently, SS-OCTA unveils a previously uncharted vascular pathological profile of BVMD that includes vascular alteration of the SCP and DCP layers, and reveals causal relationships between an abnormal vascular profile and pathological changes in retinal microstructure. 1–4 , 6 Moreover, SS-OCTA depicts with pinpoint accuracy the development of secondary choroidal neovascular membrane (CNV), particularly in cases where FFA and structural OCT have revealed equivocal findings. 7–9 …”