Original StudyANALYSIS OF FLUID VOLUME AND ITS IMPACT ON VISUAL ACUITY IN THE FLUID STUDY AS QUANTIFIED WITH DEEP LEARNINGReiter, Gregor S. MD*; Grechenig, Christoph MD*; Vogl, Wolf-Dieter PhD*; Guymer, Robyn H. PhD†; Arnold, Jennifer J. MBBS‡; Bogunovic, Hrvoje PhD*; Schmidt-Erfurth, Ursula MD*Author Information *Department of Ophthalmology and Optometry, Christian Doppler Laboratory for Ophthalmic Image Analysis, Medical University of Vienna, Vienna, Austria; †Department of Surgery (Ophthalmology), Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, and University of Melbourne, Melbourne, Australia; and ‡Marsden Eye Specialists, Parramatta, New South Wales, Australia. Reprint requests: Ursula Schmidt-Erfurth, MD, Department of Ophthalmology and Optometry, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria; e-mail: [email protected] U. Schmidt-Erfurth is a scientific consultant for Genentech, Heidelberg Engineering, Kodiak, Novartis, and Roche. R. H. Guymer reports personal fees from Bayer, Novartis, Roche Genentech, and Apellis outside the submitted work. J. J. Arnold reports personal fees and advisory board membership for Allergan, Novartis, and Bayer. None of the other authors has any financial/conflicting interests to disclose. Retina: June 2021 - Volume 41 - Issue 6 - p 1318-1328 doi: 10.1097/IAE.0000000000003023 Buy Metrics AbstractIn Brief Purpose: To investigate quantitative differences in fluid volumes between subretinal fluid (SRF)–tolerant and SRF-intolerant treat-and-extend regimens for neovascular age-related macular degeneration and analyze the association with best-corrected visual acuity. Methods: Macular fluid (SRF and intraretinal fluid) was quantified on optical coherence tomography volumetric scans using a trained and validated deep learning algorithm. Fluid volumes and complete resolution was automatically assessed throughout the study. The impact of fluid location and volumes on best-corrected visual acuity was computed using mixed-effects regression models. Results: Baseline fluid quantifications for 348 eyes from 348 patients were balanced (all P > 0.05). No quantitative differences in SRF/intraretinal fluid between the treatment arms was found at any study-specific time point (all P > 0.05). Compared with qualitative assessment, the proportion of eyes without SRF/intraretinal fluid did not differ between the groups at any time point (all P > 0.05). Intraretinal fluid in the central 1 mm and SRF in the 1-mm to 6-mm macular area were negatively associated with best-corrected visual acuity (−2.8 letters/100 nL intraretinal fluid, P = 0.007 and −0.20 letters/100 nL SRF, P = 0.005, respectively). Conclusion: Automated fluid quantification using artificial intelligence allows objective and precise assessment of macular fluid volume and location. Precise determination of fluid parameters will help improve therapeutic efficacy of treatment in neovascular age-related macular degeneration. In the FLUID study, less injections resulted in neither higher fluid volumes nor in worse best-corrected visual acuity. Macular fluid quantification offers a precise and reliable way to guide anti–vascular endothelial growth factor treatment in neovascular age-related macular degeneration.