Retinal “sweet spot” for myopia treatment

• Published in: Scientific reports Vol. 14; no. 1; pp. 26773 - 10
• Main Authors: Swiatczak, Barbara, Scholl, Hendrik P. N., Schaeffel, Frank
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 05.11.2024; Nature Publishing Group; Nature Portfolio
• Subjects: 631/378; 631/378/2613; 631/378/2613/1786; Adult; Axial length; Defocus; Emmetropization; Eye; Female; Fixation, Ocular - physiology; Fovea; Fovea Centralis; Human subjects; Humanities and Social Sciences; Humans; Male; multidisciplinary; Myopia; Myopia - physiopathology; Neurosciences; Patching; Periphery; Refraction, Ocular - physiology; Retina; Science; Science (multidisciplinary); Young Adult; Retina; Axial length; Defocus; Fovea; Emmetropization; Periphery
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-024-78300-x

We studied which retinal area controls short-term axial eye shortening when human subjects were exposed to + 3.0D monocular defocus. A custom-built infrared eye tracker recorded the point of fixation while subjects watched a movie at a 2 m distance. The eye tracker software accessed each individual movie frame in real-time and covered the points of fixation in the movie with a uniform grey patch. Four patches were programmed: (1) foveal patch (0–3 degrees), (2) annular patch (3–9 deg), (3) foveal patch (0–3 deg) combined with an annular patch (6–9 deg), and (4) full-field patch where only 6–10 deg were exposed to the defocus. Axial eye shortening was elicited similarly with full-field positive defocus and with the foveal patch, indicating that the fovea made only a minor contribution (-11 ± 12 μm vs. -14 ± 17 μm, respectively, n.s.). In contrast, patching a 3–9 degrees annular area or fovea together with an annular area of 6–9 degrees, completely suppressed the effect when compared with full-field defocus (+ 3 ± 1 μm or -2 ± 13 μm vs. -11 ± 12 μm, respectively, p  < 0.001). Finally, we found that the near-peripheral retina (6–10 degrees) is a “sweet spot” for positive defocus detection and alone can regulate eye growth control mechanism, and perhaps long-term refractive development (-9 ± 8 μm vs. full-field: -11 ± 12 μm, n.s.).