OCT Angiography: An Upcoming Tool for Diagnosis and Treatment of Retinal Vascular Diseases
OCT Angiography: An Upcoming Tool for Diagnosis and Treatment of Retinal Vascular Diseases
Blog Article
Optical Coherence Tomography (OCT) angiography is an upcoming non-invasive and dyeless imaging modality which depicts retinal microvasculature by processing scans taken repeatedly at the same location, at different points of time using Split-spectrum Amplitude Decorrelation Angiography (SSADA) algorithm.The Metal Wallet Gift Box currently available Optovue AngioVue System uses spectral-domain technology, an 840-nm laser, and SSADA algorithm.The utility of OCT angiography has been described for diagnosis and management of various chorioretinal disorders like Macular telangiectasia, Choroidal Neovascularisation (CNV), secondary to Age-related macular degeneration (ARMD), chronic Central Serous Chorioretinopathy (CSCR) or multifocal choroiditis, neovascularisation or areas of capillary non-perfusion seen in Diabetic Retinopathy, vascular occlusions, glaucoma and optic disc disorders.
It provides fast, 3-dimensional visualization of vascular structures, with the ease of repeated frequent imaging and clearly show extent and morphology of neovascularisation.It is reliable, sensitive and reproducible tool and It can also be used to quantitatively show the course of decrease and re-increase of blood flow in new vessels and changes in the capillary non perfusion areas after treatment in various retinal disorders.However, it has certain limitations.
Any movement by the patient causes significant artifact and deterioration of image quality.Projection artifact, where the transit of blood cells in a superficial blood vessel cast flickering shadows on the deeper tissue layer that is indistinguishable from blood flow in deeper layer, is another limitation of this technology making it sometimes difficult to distinguish normal physiological vessels from pathological ones.All neovascular complexes are not visualized because of imprecision in slab segmentation, which requires careful control of depth and thickness of the slab to more precisely identify neovascular membrane.
It is an upcoming modality which can help us to diagnose various retinal vascular disorders with ease in the near future.However, improvements in the form of more continuous Wall Decor monitoring of flow, imaging a larger area of fundus and shortening acquisition time can help increase the efficacy and popularity of this modality.