Progressive Choriocapillaris Changes on Optical Coherence Tomography Angiography Correlate With Stage Progression in AMD.

Purpose: We investigated the association between inner choroid flow deficit percentage (IC-FD%) using swept-source optical coherence tomography angiography (SS-OCTA) and progression of AMD. Methods: Retrospective, observational study including 64 eyes (42 participants) with early or intermediate AMD at baseline. Participants had two or more consecutive swept-source optical coherence tomography angiography covering a period of at least 18 months. Demographics, visual acuity, and AMD staging based on Beckman classification were reviewed. OCT was analyzed for hyperreflective foci, subretinal drusenoid deposits, hyporeflective drusen cores, and subfoveal choroidal thickness. IC-FD% was measured within the central 3- and 6-mm using a 16-µm slab, after compensation and binarization (Phansalkar method). Mixed-effects Cox regression models assessed the association between imaging biomarkers and AMD progression. Results: During follow-up (37 ± 9 months), 4 eyes with early AMD (31%) progressed to intermediate AMD and 30 (59%) eyes with intermediate AMD developed late AMD (19 geographic atrophy; 11 wet AMD). Baseline hyporeflective drusen core was associated with geographic atrophy development (P < 0.01), whereas greater IC-FD% (3-mm) was associated with wet AMD (P = 0.03). Time-varying analysis showed that faster subfoveal choroidal thickness reduction and IC-FD% (6-mm) increase were associated with geographic atrophy onset (P < 0.05), whereas IC-FD% (3-mm) increase was associated with wet AMD (P = 0.03). Notably, greater IC-FD% increases in the 3 mm (area under the curve = 0.72) and 6 mm (area under the curve = 0.89) were better predictive of wet AMD and geographic atrophy development, respectively. Conclusions: Our longitudinal IC-FD% assessment emphasizes the role of progressive choriocapillaris changes as a biomarker for AMD progression. Our findings support that widespread choriocapillaris alterations (6 mm) may precede progression to geographic atrophy, whereas more central choriocapillaris loss (3 mm) may provide an ischemic stimulus for wet AMD.

Decreased Macular Choriocapillaris Perfusion Correlates with Contrast Sensitivity Function in Dry Age-Related Macular Degeneration.

PURPOSE: To investigate the relationships between contrast sensitivity (CS), choriocapillaris perfusion, and other structural OCT biomarkers in dry age-related macular degeneration (AMD). DESIGN: Cross-sectional, observational study. PARTICIPANTS: One hundred AMD eyes (22 early, 52 intermediate, and 26 late) from 74 patients and 45 control eyes from 37 age-similar subjects. METHODS: All participants had visual acuity (VA) assessment, quantitative CS function (qCSF) testing, macular OCT, and 6 × 6-mm swept-source OCT angiography scans on the same day. OCT volumes were analyzed for subretinal drusenoid deposits and hyporeflective drusen cores, and to measure thickness of the outer nuclear layer. OCT angiography scans were utilized to calculate drusen volume and inner choroid flow deficit percentage (IC-FD%), and to measure the area of choroidal hypertransmission defects (HTDs). Inner choroid flow deficit percentage was measured from a 16-µm thick choriocapillaris slab after compensation and binarization with Phansalkar's method. Generalized linear mixed-effects models were used to evaluate the associations between functional and structural variables. MAIN OUTCOME MEASURES: To explore the associations between qCSF-measured CS, IC-FD%, and various AMD imaging biomarkers. RESULTS: Age-related macular degeneration exhibited significantly reduced qCSF metrics eyes across all stages compared with controls. Univariate analysis revealed significant associations between various imaging biomarkers, reduced qCSF metrics, and VA in both groups. Multivariate analysis confirmed that higher IC-FD% in the central 5 mm was significantly associated with decreases in all qCSF metrics in AMD eyes (ß = -0.74 to -0.25, all P < 0.05), but not with VA (P > 0.05). Outer nuclear layer thickness in the central 3 mm correlated with both VA (ß = 2.85, P < 0.001) and several qCSF metrics (ß = 0.01-0.90, all P < 0.05), especially in AMD eyes. Further, larger HTD areas were associated with decreased VA (ß = -0.89, P < 0.001) and reduced CS at low-intermediate frequencies across AMD stages (ß = -0.30 to -0.29, P < 0.001). CONCLUSIONS: The significant association between IC-FD% in the central 5 mm and qCSF-measured CS reinforces the hypothesis that decreased macular choriocapillaris perfusion contributes to visual function changes in AMD, which are more pronounced in CS than in VA. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Extensive Endolaser During Vitrectomy for Primary Rhegmatogenous Retinal Detachment Is Associated With Epiretinal Membrane Formation.

BACKGROUND AND OBJECTIVE: Epiretinal membrane (ERM) formation, a common complication following pars plana vitrectomy (PPV) for primary rhegmatogenous retinal detachment (RRD) repair, is associated with vision loss and metamorphopsias. Although laser retinopexy is generally associated with ERM formation, the correlation between the extent of laser treatment and ERM formation during PPV is not well established. The aim of this study was to identify risk factors associated with ERM formation including extend of endolaser retinopexy after PPV for primary RRD. PATIENTS AND METHODS: A retrospective, observational case series of 181 consecutive patients (185 eyes) who underwent PPV for primary RRD repair by a single surgeon was performed. Charts were reviewed by two independent reviewers, and de-identified data including patient characteristics and intraoperative findings such as number of laser spots placed were recorded. RESULTS: Postoperative ERM formation occurred in 75 eyes (40.5%) of which 68 (90.6%) were Stage 1, two (2.6%) were Stage 2, three (4%) were Stage 3, and two (2.6%) were Stage 4. Only one patient required secondary PPV for visually significant ERM. Patients with ERM had significantly more laser spots compared with patients with no ERM, with a mean of 807 and 519 laser spots respectively (95% CI: 387.6 to -187.3; P < 0.0001). Univariable analysis identified ≥750 endolaser spots (odds ratio [OR] = 4.0, 95% CI: 2.0 to 8.4; P < 0.0001), ≥4 retinal tears (OR = 2.8, 95%: CI 1.4 to 6.4; P = 0.005), and female sex (OR = 2.0, 95% CI: 1.1 to 3.7; P = 0.02) as significantly associated factors. After adjusting for potential confounding factors (ie, age, sex, macula status, lattice degeneration, length of symptoms, vitreous hemorrhage, number of endolaser spots, number of retinal tears) in multivariable logistic regression, ≥ 750 endolaser spots (OR = 2.4; P = 0.04) and female sex (OR = 2.4; P = 0.03) persisted as significant independent factors. CONCLUSIONS: Our study identified ≥ 750 laser spots and female sex as independent risk factors for ERM formation following PPV for RRD with an OR of 2.4 each. Although the incidence of ERM formation was generally high (40.5%), only one case required secondary PPV with ERM peeling, and visual outcomes were comparable between patients with and without ERM at final follow up. While endolaser photocoagulation is critical for successful RRD repair, consideration of the risk of ERM formation with extensive laser exposure is warranted. [Ophthalmic Surg Lasers Imaging Retina 2024;55:326-333.].