• Browning Langston posted an update 4 days, 14 hours ago

    To investigate the three-dimensional distribution and associating demographic factors of depolarization, using polarization-sensitive optical coherence tomography (PS-OCT), to evaluate melanin pigmentation in the retinal pigment epithelium (RPE) and choroid in healthy eyes.

    In total, 39 unaffected healthy eyes of 39 subjects were examined using a PS-OCT clinical prototype. The degree of depolarization, expressed as the polarimetric entropy, was assessed in the RPE, the superficial and the total choroid layer, especially in the center, the inner, or the outer areas centered at the fovea. The values and their association with the demographic data were analyzed. Near-infrared fundus autofluorescence (NIRAF) was also used, in the same manner, for the comparison. Twenty-eight of 39 eyes were measured twice to evaluate intrasession repeatability.

    Both the polarimetric entropy in the RPE and the gray level in NIRAF, decreased from the center to the periphery (P < 0.001). The polarimetric entropy in the RPE was significantly associated with age in each area (P ≤ 0.001). In the RPE and the superficial choroid, the polarimetric entropy was negatively associated with axial length in each area (P ≤ 0.002). The intraclass correlation coefficient of the polarimetric entropy in the same session was excellent in each area of the RPE, superficial choroid, or total choroid layer (0.94-0.98).

    The distribution of fundus melanin pigment-related depolarization was evaluated using PS-OCT. The depolarization was associated with the subjects’ demographic data, such as age or axial length.

    The presented information in healthy eyes provides an essential basis for the investigation into a variety of chorioretinal pathologies.

    The presented information in healthy eyes provides an essential basis for the investigation into a variety of chorioretinal pathologies.

    Because age-related macular degeneration (AMD) is a progressive disorder and advanced AMD is currently hard to cure, an accurate and informative prediction of a person’s AMD risk using genetic information is desirable for early diagnosis and potential individualized clinical management. The objective of this study was to develop and validate novel prediction models for AMD risk using large genome-wide association studies datasets with different machine learning approaches.

    Genotype data from 32,215 Caucasian individuals with age of ≥50 years from the International AMD Genomics Consortium in dbGaP were used to establish and test prediction models for AMD risk. Four different machine learning approaches-neural network, lasso regression, support vector machine, and random forest-were implemented. A standard logistic regression model using a genetic risk score was also considered.

    All machine learning-based methods achieved satisfactory performance for predicting advanced AMD cases (vs. normal controls) (area under the curve = 0.81-0.82, Brier score = 0.17-0.18 in a separate test dataset) and any stage AMD (vs. normal controls) (area under the curve = 0.78-0.79, Brier score = 0.18-0.20 in a separate test dataset). The prediction performance was further validated in an independent dataset of 783 subjects from UK Biobank (area under the curve = 0.67).

    By applying multiple state-of-art machine learning approaches on large AMD genome-wide association studies datasets, the predictive models we established can provide an accurate estimation of an individual’s AMD risk profile based on genetic information along with age. The online prediction interface is available at https//yanq.shinyapps.io/no_vs_amd_NN/.

    The accurate and individualized risk prediction model interface will greatly improve early diagnosis and enhance tailored clinical management of AMD.

    The accurate and individualized risk prediction model interface will greatly improve early diagnosis and enhance tailored clinical management of AMD.

    Choroideremia and RPGR-associated retinitis pigmentosa (RP) are two distinct inherited rod-cone degenerations, where good visual acuity (VA) is maintained until late disease stages, limiting its usefulness as a disease marker. Low luminance VA and low luminance deficit (standard VA minus low luminance VA) may be more sensitive visual function measures.

    Standard VA was obtained using Early Treatment Diabetic Retinopathy Study letter charts (Precision Vision,Bloomington, IL, USA). Low luminance VA was assessed using a 2.0-log unit neutral density filter, with the same chart setup, without formal dark adaptation. Doramapimod supplier Mean central retinal sensitivity was assessed using MAIA microperimetry (Centervue SpA, Padova, Italy). Optical coherence tomography imaging was attained with Heidelberg Eye Explorer software (Heidelberg Engineering, Heidelberg, Germany).

    Twenty-four male participants with confirmed pathogenic RPGR mutations, 44 male participants with confirmed pathogenic CHM mutations, and 62 age-matched controls underwent clinical assessment prior to clinical trial recruitment. Low luminance VA was significantly reduced in both disease groups compared to controls. The low luminance deficit correlated with microperimetry retinal sensitivity and ellipsoid zone width. Eleven participants with moderate VA had poor low luminance VA (subsequently a large low luminance deficit), no detectable microperimetry sensitivity, and severely constricted ellipsoid zone widths.

    Low luminance VA and subsequently low luminance deficit are useful markers of central macular visual function in both choroideremia and RPGR-associated RP, when standard VA is preserved.

    Low luminance visual acuity and low luminance deficit are useful vision measures in two distinct rod-cone degenerations and may be useful in other retinal degenerations.

    Low luminance visual acuity and low luminance deficit are useful vision measures in two distinct rod-cone degenerations and may be useful in other retinal degenerations.

    To describe normative values for choroidal thickness in newborns and characterize their relationship to vitreoretinal features.

    Term newborns underwent awake, handheld swept-source optical coherence tomography (SS-OCT) in this prospective cohort study. An automated segmentation algorithm followed by manual adjustments measured choroidal thickness at the fovea and five perifoveal locations. Two masked, trained graders, with a third mediating disagreements, analyzed scans for vitreoretinal findings. OCT vitreoretinal findings, including dome-shaped macula, subretinal fluid, punctate hyperreflective vitreous opacities, persistent inner retinal layers, foveal ellipsoid zone, tractional and non-tractional vitreous bands, epiretinal membrane, cystoid macular edema, vessel elevation, scalloped retinal layers, hyporeflective vessels, and retinal spaces, were assessed and correlated with foveal choroidal thickness using a generalized linear mixed model.

    Fifty-nine eyes of 39 infants (mean gestational age, 39.5 weeks; 18 male, 46%) were included.