Camachocooke7288
Agreement between 30° and 50° images showed a similar bias as when comparing data obtained with the same camera angle setting but exhibited larger confidence intervals (arteries bias = 0.21% [9.04/-8.62]%; veins bias = 0.71% [14.82/-13.40]%).
Averaging methods yielded the best agreement; there was little difference in average arterial and venous oxygen saturation between protocols, which analyze all vessels versus the four largest vessels. The least agreement was found for single vessel measurements and comparisons between different camera angles.
Standardization of image capture protocols (same image size and undertaking a vessel averaging approach for oxygenation analysis) will enhance the detection of smaller physiological changes in eye disease.
Standardization of image capture protocols (same image size and undertaking a vessel averaging approach for oxygenation analysis) will enhance the detection of smaller physiological changes in eye disease.
microRNAs (miRNAs) mediate the pathological mechanisms of diabetic retinopathy. In this study, we compared miRNA expression profiles in the vitreous between patients with proliferative diabetic retinopathy (PDR) and patients with a macular hole as non-diabetic controls, and between PDR patients treated with anti-vascular endothelial growth factor (VEGF) therapy and untreated PDR patients.
Vitreous samples of non-diabetic and PDR patients were screened for miRNAs with quantitative polymerase chain reaction (qPCR) panels. miRNA candidates were validated in vitreous samples of a second, independent cohort. In addition, the effect of anti-VEGF therapy was investigated in the vitreous of a third study population consisting of PDR patients who had not received anti-VEGF therapy and PDR patients who had received preoperative anti-VEGF therapy.
During screening, seven miRNAs were found to be significantly higher in the vitreous of PDR patients, whereas two miRNAs were found to be significantly lower compared with non-diabetic controls. Validating the expression of these miRNAs in a second cohort resulted in the identification of six miRNAs that were expressed at significantly higher rates in the vitreous of PDR patients hsa-miR-20a-5p, hsa-miR-23b-3p, hsa-miR-142-3p, hsa-miR-185-5p, hsa-miR-326, and hsa-miR-362-5p. see more Among these six miRNAs, hsa-miR-23b-3p levels were lower in the anti-VEGF-treated group of PDR patients compared with untreated PDR patients.
In this study, we identified six miRNAs that are expressed more highly in PDR patients and one miRNA that is expressed at a lower levels in anti-VEGF-treated PDR patients.
miRNAs identified in the vitreous of PDR patients may improve our understanding of the mechanisms leading to PDR.
miRNAs identified in the vitreous of PDR patients may improve our understanding of the mechanisms leading to PDR.
To determine the rates and develop an initial risk prediction model for nonadherence to post screening ophthalmic referral (PSOR) in type 2 diabetes mellitus (T2DM) patients attending a national diabetic retinopathy screening program in Singapore.
Data from 2387 patients with T2DM (mean [standard deviation] age 66.5 [11] years; 52.5% female patients) who underwent teleophthalmic screening between 2010 and 2014 under the Singapore Integrated Diabetic Retinopathy Program were extracted from electronic medical records. All were referred for tertiary ophthalmic management at the Singapore National Eye Centre (SNEC). Nonadherence was defined as not attending the SNEC appointment within 6 months of the assigned appointment date. Regression analysis using traditional modified Poisson and conditional inference models was used to construct and evaluate the discriminative ability of the preliminary risk prediction model to identify nonadherent individuals.
Nonadherence rates to PSOR was 12.7% (95% confidence interval, 11.4%-14.1%). In traditional multivariable models adjusted for sociodemographic, lifestyle, and ocular factors, nonadherent individuals had higher triglyceride levels and were less likely to have a referable eye condition (
< 0.05). This model was able to identify nonadherent individuals with an accuracy (area under the curve) of 84%. In contrast, the conditional inference model was able to achieve similar discriminative ability using only participants' ocular health characteristics.
The rates of nonadherence to PSOR in Singaporean individuals with T2DM is low, with better ocular health being strongly predictive of nonadherence in our Asian population.
Our results may inform interventions to decrease nonadherence to PSOR.
Our results may inform interventions to decrease nonadherence to PSOR.
Wound healing processes in a rat corneal alkali burn model were observed using low-vacuum scanning electron microscopy (LV-SEM), a new observation method that can use paraffin sections for light microscopic immunostaining.
Injured cornea was observed under immunohistochemistry, LV-SEM, and transmission electron microscopy. In LV-SEM, periodic acid-methenamine silver staining was used to observe collagen and platinum blue staining was used to observe vascular endothelial cells. Analyses of the messenger RNA expression involved in neovascularization processes after wound creation were also performed.
LV-SEM depicted progression of corneal wound healing in a stereoscopic fashion. In neovascularization processes after wound creation, LV-SEM with osmification clearly demonstrated detachment of pericytes from the vascular endothelial cells, in association with up-regulation of angiopoietin-2 messenger RNA expression.
LV-SEM enables high magnification observation of paraffin sections used for immunohistochemistry. LV-SEM provides easy, detailed observations and offers a promising new observational modality in the field of ophthalmology.
High magnification analysis was easily available using LV-SEM with conventional paraffin sections for light microscopy.
High magnification analysis was easily available using LV-SEM with conventional paraffin sections for light microscopy.
While using their amblyopic eye, individuals with strabismic amblyopia count inaccurately and underestimate the number of features. These deficits are attributed to limitations in high-level cortical functions and attention. In the current study, we examined whether feature counting is affected in strabismic and anisometropic amblyopia during dichoptic viewing, a setup that can better capture binocular function disruptions.
Through a mirror stereoscope, Gabor patches were presented for 200 msec (Experiment 1) or 350 msec (Experiment 2) in both the left eye and the right eye of observers, who were required to combine the percepts and report the total number of patches. Counting performance and errors were compared across amblyopic groups and normal-sighted observers. The contribution and relation of each eye to performance was also evaluated.
Anisometropic and strabismic amblyopia groups counted inaccurately and underestimated the number of features compared to the normal-sighted group. In both amblyopic groups, the amblyopic eye contributed less in comparison to the fellow eye. The strabismic group exhibited worse performance, and a more pronounced difference in eye contribution, in comparison to the anisometropic group.
Overall, our results support the view of higher-level cortical and binocular function deficits in amblyopia.
The current study bridges the gap between research on high-cortical function deficits and clinical binocular function disruptions in amblyopia, which can help us better understand the neural mechanism of amblyopia and inform clinical therapeutic tasks and strategies.
The current study bridges the gap between research on high-cortical function deficits and clinical binocular function disruptions in amblyopia, which can help us better understand the neural mechanism of amblyopia and inform clinical therapeutic tasks and strategies.
To develop a new method of manufacturing contact lens-shaped crosslinked amniotic membranes (AMs) using glutaraldehyde (GA) and dialdehyde starch (DAS) as crosslinking agents.
Amniotic membranes were placed on a curved plastic mold and crosslinked with either 4.5% DAS or 1% GA, after which their physical properties and biological safety were evaluated.
The tensile strength of the GA- and DAS-crosslinked samples was much increased compared with that of normal AMs. Neither crosslinking process affected AM transparency. Although the GA-crosslinked AM showed better enzymatic resistance, its physiological structure was severely damaged after the crosslinking process. On the other hand, compared with the GA-crosslinked AM, the DAS-crosslinked AM showed higher growth factor concentrations and better biocompatibility, similar to normal AMs. link2 In addition, the DAS-crosslinked AM was effective in the recovery of corneal epithelial wounds and was well maintained over 3 days without decentration or degradation on the ocular surface in human subjects.
Contact lens-shaped AMs were successfully prepared with crosslinking agents. Crosslinking with DAS did not affect the structural properties or biological activity of the AMs, and the improved mechanical properties helped the AM to maintain its curved shape. link3 This crosslinking method allowed us to transplant AMs into patients' eyes without sutures.
Sutureless fixation of contact lens-shaped AMs would be very convenient and safe for the treatment of corneal surface disease.
Sutureless fixation of contact lens-shaped AMs would be very convenient and safe for the treatment of corneal surface disease.
To determine local ocular tissue levels of the bile acid, tauroursodeoxycholic acid (TUDCA), in the pig model using oral, intravenous (IV), intravitreal injection (IVitI) and low- and high-dose suprachoroidal, sustained-release implants (SCI-L or SCI-H).
Forty-six pigs (92 globes) were included in the study. TUDCA was delivered orally in 5 pigs, IV in 4, IVitI in 6, SCI-L in 17, and SCI-H in 14. Testing timeframes varied from the same day (within minutes) for IV; 1 to 6 days, oral; and 1 to 4 weeks, IVitI and SCI. Enucleated globes were dissected, specimens from specific tissues were separated, and TUDCA was extracted and quantified using mass spectrometry.
The highest TUDCA tissue levels occurred after IV delivery in the macula (252 ± 238 nM) and peripheral retina (196 ± 171 nM). Macular choroid and peripheral choroid levels were also high (1032 ± 1269 and 1219 ± 1486 nM, respectively). For IVitI delivery, macular levels at day 6 were low (0.5 ± 0.5 nM), whereas peripheral choroid was higher (15.3 ± 16.7 nM). Neither the SCI-L nor SCI-H implants delivered meaningful macular doses (≤1 nM); however, peripheral retina and choroid levels were significantly higher. Bile acid isoforms were found in the serum specimens.
The highest TUDCA tissue levels in the pig model were obtained using IV delivery. Oral delivery was associated with reasonable tissue levels. Local delivery (IVitI and SCI) was able to achieve measurable local ocular tissue levels.
Diffusional kinetics from the suprachoroidal space follow the choroidal blood flow, away from the macula and toward the periphery.
Diffusional kinetics from the suprachoroidal space follow the choroidal blood flow, away from the macula and toward the periphery.
