Репозиторий Университета

Background: To investigate age-related severity, patterns of retinal structural damage, and functional visual recovery in pediatric and adult cohorts of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) optic neuritis (ON). Methods: All MOGAD patients from the 5 participating centers were included. Patients with initial manifestation <18 years were included in the pediatric (MOGAD ) cohort and patients with ≥18 years in the adult (MOGAD ) cohort. For patients with MOGAD ON, examinations at least ≥6 months after ON onset were included in the analyses. Using spectral domain optical coherence tomography (SD-OCT), we acquired peripapillary retinal nerve fiber layer thickness (pRNFL) and volumes of combined ganglion cell and inner plexiform layer (GCIPL). High- and 2.5% low-contrast visual acuity (HCVA, LCVA) and visual-evoked potentials (VEP) were obtained. Results: Twenty MOGAD  (10.3±3.7 years, 30 MOGAD ON eyes) and 39 MOGAD  (34.9±11.6 years, 42 MOGAD ON eyes) patients were included. The average number of ON episodes per ON eye was similar in both groups (1.8±1.3 and 2.0±1.7). In both pediatric and adult MOGAD, ON led to pronounced neuroaxonal retinal atrophy (pRNFL: 63.1±18.7 and 64.3±22.9 μm; GCIPL: 0.42±0.09 and 0.44±0.13 mm , respectively) and moderate delay of the VEP latencies (117.9±10.7 and 118.0±14.5 ms). In contrast, visual acuity was substantially better in children (HCVA: 51.4±9.3 vs. 35.0±20.6 raw letters, p=0.001; LCVA: 22.8±14.6 vs. 13.5±16.4, p=0.028). Complete visual recovery (HCVA-logMAR 0.0) occurred in 73.3% of MOGAD  and 31% MOGAD  ON eyes, while 3.3% and 31% demonstrated moderate to severe (logMAR > 0.5) visual impairment. Independent of retinal atrophy, age at ON onset significantly correlated with visual outcome. Conclusion: Pediatric MOGAD ON showed better visual recovery than adult MOGAD ON despite profound and almost identical neuroaxonal retinal atrophy. Age-related cortical neuroplasticity may account for the substantial discrepancy between structural changes and functional outcomes. ped adult ped adult 3 ped adults

© 2018 Society of Photo-Optical Instrumentation Engineers (SPIE). We present the nanoparticle-enabled experimentally trained wavelet-domain denoising method for optical coherence tomography (OCT). It employs an experimental training algorithm based on imaging of a test-object, made of the colloidal suspension of the monodisperse nanoparticles and contains the microscale inclusions. The geometry and the scattering properties of the test-object are known a priori allowing us to set the criteria for the training algorithm. Using a wide set of the wavelet kernels and the wavelet-domain filtration approaches, the appropriate filter is constructed based on the test-object imaging. We apply the proposed approach and chose an efficient wavelet denoising procedure by considering the combinations of the decomposition basis from five wavelet families with eight types of the filtration threshold. We demonstrate applicability of the wavelet-filtering for the in vitro OCT image of human brain meningioma. The observed results prove high efficiency of the proposed OCT image denoising technique.

Lutein and zeaxanthin are carotenoid pigments that affect the function of the visual analyzer. They selectively accumulate in the yellow spot of the retina, form macular pigment and determine the density of the retina macula. Lutein and zeaxanthin slow down the progression of age-related macular degeneration, a leading cause of senior-age blindness. The main food sources of non-vitamin carotenoids are green leafy vegetables, zucchini, pumpkin, green peas, broccoli. The aim of the study is a retrospective assessment of the levels and sources of alimentary intake of lutein and zeaxanthin in young people and research of the effect of lutein and zeaxanthin in the diet on macula density. A specially designed questionnaire was used to quantify the content of lutein and zeaxanthin in the diet, reflecting the amount of consumption of the main sources of these carotenoids on the day preceding the survey. A non-invasive non-contact method of optical coherence tomography of the retina was used to determine the density of the macula. The study involved 96 students of Sechenov University at the age of 21-27 years. The study found that only 6.25% of the respondents had daily intake of lutein and zeaxanthin of 6 mg or more, 8.33% had 4.6-5.9 mg, 8.33% had 3.0-4.5 mg, in 18.75% - 1.5-2.9 mg, in 45.83% <1.4 mg 12.5% of respondents didn't include sources of lutein and zeaxanthin in the diet. The more common sources of lutein and zeaxanthin in the diet were eggs and fresh tomatoes. Retinal density indices corresponded to the age standards in the majority of the examined. In 8.3% surveyed the thickness of the retina was decreased, and 4.2% had higher thickness of the retina in comparison with the standards. Significant differences in the Central subfield thickness in men and women were revealed. There was no dependence of the levels of lutein and zeaxanthin coming from food sources on the retina thickness indicators.

The article reviews the results of using optical coherence tomography (OCT) - a non-invasive non-contact examination method for obtaining a tomographic slice image of the site of glaucoma surgery. The method helped reveal the functional relationships between the newly created outflow pathways and various parameters of the filtering bleb such as its linear dimensions, wall structure, presence of microcysts, position of drainage, etc. Due to its high resolution and noninvasiveness, OCT can be reliably used to examine the structure of aqueous outflow pathways in different postoperative periods with accuracy close to morphometric. The amount of data that had been obtained with the method has allowed the creation of new classifications and clarification of OCT-relevant prognostic signs for glaucoma surgery site.

© 2018 SPIE. We have proposed a wavelet-domain de-noising technique for imaging of human brain malignant glioma by optical coherence tomography (OCT). It implies OCT image decomposition using the direct fast wavelet transform, thresholding of the obtained wavelet spectrum and further inverse fast wavelet transform for image reconstruction. By selecting both wavelet basis and thresholding procedure, we have found an optimal wavelet filter, which application improves differentiation of the considered brain tissue classes-i.e. malignant glioma and normal/intact tissue. Namely, it allows reducing the scattering noise in the OCT images and retaining signal decrement for each tissue class. Therefore, the observed results reveals the wavelet-domain de-noising as a prospective tool for improved characterization of biological tissue using the OCT.