Choriocapillaris flow impairment predicts the development and enlargement of drusen

Purpose: To evaluate the choriocapillaris flow in regions of enlarged or new incident drusen in patients with early and intermediate age-related macular degeneration (AMD). Methods: We retrospectively reviewed and analyzed structural optical coherence tomography (OCT) and OCT angiography (OCTA) images of consecutive patients with early or intermediate AMD evaluated at the Doheny-UCLA Eye Centers between 2015 and 2018. All patients were imaged using a Cirrus OCT, and only one eye was included in the study. To be eligible for this analysis, patients were required to have a 3 7 3-mm OCTA scan acquired during the first visit (considered as baseline) and a fovea-centered 512 7 128 macular cube (6 7 6 mm) acquired at both the baseline visit and after a minimum of 1 year follow-up. The drusen maps generated from the macular cubes were used to generate a drusen area (DA) measurement and compute the difference between baseline and follow-up (\u394DA). After registering the structural OCTs to the baseline choriocapillaris (CC) OCTA, we analyzed and compared the baseline flow deficits (FD) within drusen-free region (FDDF), regions into which drusen enlarged or expanded at follow-up (FDEN), and regions in which new incident drusen (FDND) appeared at follow-up. Results: Forty-six patients were eligible for the analysis and had a mean follow-up of 1.47 years. Twelve eyes of 12 subjects had a \u394DA < 0.1 mm2. In these eyes, only the FDDF was calculated (40.37 \ub1 2.29%) and it was not significantly different from the FDDF of eyes with \u394DA 65 0.1 mm2 (40.25 \ub1 4.37%, p = 0.849). When comparing the different regions within the eyes with \u394DA 65 0.1 mm2, there was no significant difference between FDED and FDND (43.61 \ub1 4.36% and 44.16 \ub1 2.38%, p = 528), but both were significantly higher than FDDF (p = 0.001 and p < 0.001, respectively). Conclusions: Significant CC flow impairment is present under regions of intact retinal pigment epithelium (RPE) where existing drusen will enlarge into or new drusen will appear within 2 years. These findings suggest that location of drusen may not be stochastic but may be driven by regional deficits in the choriocapillaris

The interplay of agency, culture and networks in field evolution

We examine organizational field change instigated by activists. Contrary to existing views emphasizing incumbent resistance, we suggest that collaboration between incumbents and challenger movements may emerge when a movement's cultural and relational fabric becomes moderately structured, creating threats and market opportunities but remaining permeable to external influence. We also elucidate how lead incumbents' attempts at movement cooptation may be deflected through distributed brokerage. The resulting confluence of cultural and relational "structuration" between movement and field accelerates the pace but dilutes the radicalness of institutional innovation, ensuring ongoing, incremental field change. Overall, this article contributes to the emergent literature on field dynamics by uncovering the evolution and outcomes of collaborative work at the intersection of social movements and incumbent fields

Relationship between choriocapillaris flow and scotopic microperimetry in early and intermediate age related macular degeneration

Purpose: To evaluate the correlation between choriocapillaris (CC) flow alterations and scotopic macular sensitivity (sMS) in patients with early and intermediate age-related macular degeneration (AMD). Design: prospective cross-sectional study METHODS: We acquired two 3x3mm and two 6x6mm swept-source optical coherence tomography angiography (OCTA) images of one eye of consecutive early or intermediate AMD patients at the Doheny UCLA Eye Centers. After 30 minutes of dark adaptation, the same eye underwent scotopic microperimetry with an 18\ub0-wide grid (52 stimuli) centered on the fovea. The two en-face CC angiograms obtained from each scan pattern were compensated for signal loss and averaged. Main outcome measures: correlation between percentages of flow deficits (FD3mm and FD6mm) and sMS in the central 10\ub0 (MS10) and the overall pattern (MS18). Results: Thirty eyes of 30 patients were enrolled, with 14 (46.7%) having subretinal drusenoid deposits (SDD). In the averaged OCTA scans, the FD3mm was 12.56\ub12.41 % while the FD6mm was 9.33\ub11.84 %. The mean MS10 and MS18 were 13.84\ub15.89 dB and 14.64\ub15.21 dB, respectively. For the MS10, the multivariate regression analysis showed a significant association only with FD3mm (\u3b2:-0.628, p<0.001) while the MS18 was significantly correlated with both SDD (\u3b2:-0.32, p=0.047) and FD6mm (\u3b2:-0.473, p=0.005). Conclusions: Our study reports a significant correlation between the CC flow impairment and the sMS in eyes with early or intermediate AMD. If replicated in future longitudinal studies, the choriocapillaris FD may prove to be a useful parameter for evaluating the functional status and prognosis of these eyes

A Workshop on Measuring the Progression of Atrophy Secondary to Stargardt Disease in the ProgStar Studies: Findings and Lessons Learned

The Progression of Atrophy Secondary to Stargardt Disease (ProgStar) studies were designed to measure the progression of Stargardt disease through the use of fundus autofluorescence imaging, optical coherence tomography, and microperimetry. The overarching objectives of the studies were to document the natural course of Stargardt disease and identify the most appropriate clinical outcome measures for clinical trials assessing the efficacy and safety of upcoming treatments for Stargardt disease. A workshop organized by the Foundation Fighting Blindness Clinical Research Institute was held on June 11, 2018, in Baltimore, MD, USA. Invited speakers discussed spectral-domain optical coherence tomography, fundus autofluorescence, and microperimetry methods and findings in the ProgStar prospective study. The workshop concluded with a panel discussion of optimal endpoints for measuring treatment efficacy in Stargardt disease. We summarize the workshop presentations in light of the most current literature on Stargardt disease and discuss potential clinical outcome measures and endpoints for future treatment trials