Objective To evaluate the association of subretinal hyper-reflective material (SHRM) with visual acuity (VA), geographic atrophy (GA) and scar in the Comparison of Age related Macular Degeneration Treatments Trials (CATT) Design Prospective cohort study within a randomized clinical trial. Participants The 1185 participants in CATT. Methods Participants were randomly assigned to ranibizumab or bevacizumab treatment monthly or as-needed. Masked readers graded scar and GA on fundus photography and fluorescein angiography images, SHRM on time domain (TD) and spectral domain (SD) optical coherence tomography (OCT) throughout 104 weeks. Measurements of SHRM height and width in the fovea, within the center 1mm2, or outside the center 1mm2 were obtained on SD-OCT images at 56 (n=76) and 104 (n=66) weeks. VA was measured by certified examiners. Main Outcome Measures SHRM presence, location and size, and associations with VA, scar, and GA. Results Among all CATT participants, the percentage with SHRM at enrollment was 77%, decreasing to 68% at 4 weeks after treatment and 54% at 104 weeks. At 104 weeks, scar was present more often in eyes with persistent SHRM than eyes with SHRM that resolved (64% vs. 31%; p<0.0001). Among eyes with detailed evaluation of SHRM at weeks 56 (n=76) and 104 (n=66), mean [SE] VA letter score was 73.5 [2.8], 73.1 [3.4], 65.3 [3.5], and 63.9 [3.7] when SHRM was absent, present outside the central 1mm2, present within the central 1mm2 but not the foveal center, or present at the foveal center (p=0.02). SHRM was present at the foveal center in 43 (30%), within the central 1mm2 in 21 (15%) and outside the central 1mm2 in 19 (13%). When SHRM was present, the median maximum height in microns under the fovea, within the central 1 mm2 including the fovea and anywhere within the scan was 86; 120; and 122, respectively. VA was decreased with greater SHRM height and width (p<0.05). Conclusions SHRM is common in eyes with NVAMD and often persists after anti-VEGF treatment. At 2 years, eyes with scar were more likely to have SHRM than other eyes. Greater SHRM height and width were associated with worse VA. SHRM is an important morphological biomarker in eyes with NVAMD.
These data suggest that decreases in plasma free-VEGF levels are greater after treatment with aflibercept or bevacizumab compared with ranibizumab at 4 weeks. At 52 and 104 weeks, a greater decrease was observed in bevacizumab versus ranibizumab. Results from 2 subgroups of participants who did not receive injections within at least 1 month and 2 months before collection suggest similar changes in VEGF levels after stopping injections. It is unknown whether VEGF levels return to normal as the drug is cleared from the system or whether the presence of the drug affects the assay's ability to accurately measure free VEGF. No significant associations between VEGF concentration and systemic factors were noted.
Angiotensin II (ANG II)-mediated catecholamine release and its possible contribution to the pressor response was assessed in baroreceptor-denervated rats. Neonatal male Sprague-Dawley rats were injected with the sympatholytic drug, guanethidine monosulphate (50 mg/kg s.c., 6 days/week) for 40 days. Plasma catecholamine concentrations were measured using a 3H-radioenzymatic assay as follows: (a) before and 30 s after the injection of saline or ANG II (79.3 pmol/kg i.v.), at the peak of the pressor response, then 50 s and 80 s thereafter, in guanethidine-treated (GUAN) and saline-injected (SHAM) rats, and (b) before and after adrenalectomy (ADX), following the same time-sequence for ANG II as in (a). Peak pressor responses to graded doses of ANG II (6.6, 26.4, 53.0 and 79.3 pmol/kg i.v.) were measured in GUAN+ADX and ADX rats. Destruction of peripheral sympathetic nerves was confirmed by measurements of plasma noradrenaline (NA), adrenaline (AD) and dopamine (DA) concentrations and by changes in pressor responses and heart rates following i.v. doses of tyramine. ANG II induced significantly (P < 0.05) greater pressor responses in GUAN+ADX rats than in ADX rats, especially after the 53.0 and 79.3 pmol/kg doses. Plasma AD concentrations increased within seconds after the pressor response to ANG II in both GUAN and SHAM rats but there was no change in plasma NA or DA concentrations (P < 0.05). ANG-II-mediated AD release from the adrenal medulla may contribute to the overall pressor action of the peptide. The vasculature became more sensitive to ANG II at a time when NA and DA depletion occurred following sympathectomy and/or adrenalectomy. This heightened sensitivity to ANG II was not due to a decrease in circulating ANG II in sympathectomized rats because even though plasma renin activity fell from 6.54 +/- 0.52 to 3.77 +/- 0.26 ng ANG I/ml per h it remained within the normal range.
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.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.