Purpose-To compare the measurements of visual acuity (VA) results measured with Snellen and Early Treatment Diabetic Retinopathy Study (ETDRS) charts in eyes with and without age-related macular degeneration (AMD). Design-Cross-sectional study. Participants-One hundred four participants (190 eyes) selected from a university retina practice; 80 participants (142 eyes) had some degree of AMD. Methods-Visual acuity was measured in each patient using standard procedure with both snellen and ETDRS charts in random order. Statistical analysis of the results was performed. Main Outcome Measures-Difference in VA measured by both charts in logarithm of minimal angle of resolution (logMAR) notations. Results-Overall, the mean Snellen VA was 0.78 logMAR (= 20/120), and the mean ETDRS VA in the same eye was 0.54 logMAR (= 20/70; P<0.001). In the low vision group (<20/200), represented by patients with AMD, the average difference in number of lines was considerably larger than in the good vision range (>20/30). On average, 20/200 on Snellen was 20/95 on ETDRS (>3 lines difference), and 20/30 on Snellen was 20/25 on ETDRS (<1 line difference). Conclusion-Our results show poor agreement between the Snellen and ETDRS charts, and it was more pronounced in the group with poor vision. The ETDRS measurements yielded better VA, particularly in participants with vision <20/200 (representing more advanced AMD patients). We suggest taking these findings into consideration when comparing outcomes in clinical practices (which typically measure VA using standard Snellen charts) with outcomes from clinical trials (which typically measure VA using ETDRS charts). Visual acuity (VA) in clinical settings is an ability to discriminate two stimuli separated in space at high contrast compared with the background. This simple measure detects most of the
Aim-To determine the suitability of porous silicon photonic crystals for intraocular drug-delivery.Methods-A rugate structure was electrochemically etched into a highly doped p-type silicon substrate to create a porous silicon film that was subsequently removed and ultrasonically fractured into particles. To stabilise the particles in aqueous media, the silicon particles were modified by surface alkylation (using thermal hydrosilylation) or by thermal oxidation. Unmodified particles, hydrosilylated particles and oxidised particles were injected into rabbit vitreous. The stability and toxicity of each type of particle were studied by indirect ophthalmoscopy, biomicroscopy, tonometry, electroretinography (ERG) and histology.Results-No toxicity was observed with any type of the particles during a period of >4 months. Surface alkylation led to dramatically increased intravitreal stability and slow degradation. The estimated vitreous half-life increased from 1 week (fresh particles) to 5 weeks (oxidised particles) and to 16 weeks (hydrosilylated particles). Conclusion-The porous silicon photonic crystals showed good biocompatibility and may be used as an intraocular drug-delivery system. The intravitreal injectable porous silicon photonic crystals may be engineered to host a variety of therapeutics and achieve controlled drug release over long periods of time to treat chronic vitreoretinal diseases.There is an important medical need for a minimally invasive, controllable and monitorable drug-delivery system that would enable long-acting local treatment of intraocular diseases affecting the retina and choroid. In particular, diseases such as choroidal neovascularisation (CNV) in age-related macular degeneration (ARMD), proliferative vitreoretinopathy (PVR) associated with retinal detachment and trauma, and refractory uveitis would benefit greatly. For those chronic refractory diseases, drug delivery to the vitreous, retina and choroid is a challenging task due to the formidable obstacles posed by the blood-retinal barrier and the tight junctions of the retinal pigment epithelium. With systemic administration, only small fractions of drug reach the target, requiring large and potentially toxic doses. An ideal method of retinal drug delivery would provide a locally sustained release for prolonged periods of time. Due to the short vitreous half-life of most injectable intravitreal drugs, frequent administrations are necessary. Intravitreal injection has become standard in clinical practice and trials; however, We have investigated self-assembling liposomes and, most recently, a crystalline drug-delivery material to achieve intraocular long-lasting release of selected antiviral and antiproliferative compounds. 3 4 In particular, the lipid prodrug-delivery system is not feasible for delivery of large molecular compounds such as polypeptides and proteins, which are becoming increasingly important in the treatment of eye diseases. Other systems consisting of biodegradable and bioerodible polymeric microparticles have...
Both FA and high-resolution OCT are highly sensitive techniques and correlate well in detection of ME. However, there is a small chance that when performed alone they might miss existing subtle ME.
The intravitreous injectable lipid prodrugs of AraG and 5-fluoro-2'-deoxyuridine could be long-lasting, slow-release, antiproliferative compounds to treat unwanted intraocular proliferation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.