{
  "abstract": "Objective To investigate the relationship between photopic pupil size, refractive state and foveal anatomy in healthy adults, in the context of emmetropisation and myopia.Methods and analysis In this cross-sectional study, pupil sizes were recorded in 80 healthy adults (28±8 years/55 women) using a custom-built high-resolution pupil tracker (0.03 mm/pixel). Daylight lamps provided two high-luminance conditions (6.5k and 10k cd/m²). Objective refraction and axial length were measured, and additionally high-resolution optical coherence tomography (OCT) was applied to record retinal volume scans of the fovea. OCT B-scans were automatically segmented for the internal limiting membrane and retinal pigment epithelium layers by the instrument algorithm. Additionally, the ellipsoid and phagosome zones defining the outer segment lengths were determined by a custom-made algorithm. Associations between photopic pupil size, refractive state, axial length and foveal metrics were analysed with correlation and multivariable regression.Results Photopic pupil sizes at 6.5k cd/m² ranged from 1.77 to 3.38 mm (2.33±0.26 mm). Spherical equivalent of refraction ranged from −9.4 to +4.9 D (−1.24±2.29 D), and axial length ranged from 21.0 to 27.0 mm (23.9±1.2 mm). Photopic pupil size was significantly correlated with axial length and refractive state (all p≤0.01), although the explained variance was modest (R 2 up to 0.09). Outer segment length and foveal hill distance were significantly associated with refractive state (all p<0.05).Conclusion The association of photopic pupil size with axial length and refractive state, alongside foveal parameters being linked to refractive state but not to pupil size (exception: nasal hill height), suggests a potential interplay between foveal architecture and emmetropisation. Further investigation via longitudinal studies of children will be required. The main limitation of this study is the under-representation of high-myopes.",
  "authors": [
    {
      "affiliations": [
        "Carl Zeiss Vision International GmbH, Aalen, Germany"
      ],
      "name": "Niklas Domdei"
    },
    {
      "affiliations": [
        "Optics Group, School of Physics, University College Dublin, Dublin, Ireland"
      ],
      "name": "Brian Vohnsen"
    },
    {
      "affiliations": [
        "Carl Zeiss Vision International GmbH, Aalen, Germany",
        "Institut for Ophthalmic Research, Eberhard Karls Universitat Tubingen, Tubingen, Germany"
      ],
      "name": "Siegfried Wahl"
    },
    {
      "affiliations": [
        "Department of Ophthalmology, University Hospital Bonn, Bonn, Germany"
      ],
      "name": "Wolf Harmening"
    }
  ],
  "title": "Photopic pupil size, foveal anatomy and emmetropisation: a cross-sectional study in adult eyes",
  "uid": "df8f2e9e-0d32-5358-93bd-0d48d0b516c8"
}