OCT-angiography in neurodegenerative diseases examination

Neurodegenerative diseases (NDD) are disorders characterized by a progressive loss of selectively vulnerable populations of neurons, accompanied by a break in connections between parts of the nervous system, imbalance of genes and the delivery of appropriate neurotransmitters, leading to memory impairment, movement disorders and cognitive impairment. Pathogenetic mechanisms are associated with accumulation of abnormal proteins (extracellular amyloid β-protein, α-synuclein protein etc) as well as with autoimmune inflammation. The signs of these changes in retina can be considered as markers of neurodegenerative process. The exact etiology of NDD has not been fully understood yet, but the role of impaired cerebral geodynamics, which determines the development and aggravates the progression of neurodegeneration, has been proven. The structure and microcirculation of retina have similar features with cerebral blood vessels and morphological changes of retina and brain are identical. Since NDD are more often diagnosed at advanced stages, it is necessary to identify useful biomarkers that can be used for early diagnosis and monitoring of the degree of neuronal degeneration. In cases of NDD, there is a decreasing of density of retinal vessels of superficial and deep capillary plexus, as well as expansion of the foveolar avascular zone, the severity of this changes varies with the stage of the disease. The using of optical coherence tomography in the angiography mode as a non-invasive, fast, informative and affordable research method based on modern capabilities of multimodal imaging, seems to be the most relevant and in demand in clinical practice.