Luminance Thresholds and Their Correlation With Retinal Structure in X-Linked Retinoschisis

Invest Ophthalmol Vis Sci. 2021 Oct 4;62(13):25. doi: 10.1167/iovs.62.13.25.


Purpose: To provide a comprehensive analysis of light- and dark-adapted luminance thresholds and their associations with retinal structure in X-linked retinoschisis (XLRS).

Methods: Nine subjects with XLRS and 10 visually-normal individuals participated. Threshold was measured at 15 locations along the horizontal meridian of the visual field at several adaptation levels (5 × 10-5 to 50 cd/m2) after dark-adaptation. The relationship between threshold and adaptation level across the field was described using a standard "threshold-versus-illuminance" model. Optical coherence tomography images were obtained and segmented to quantify outer nuclear layer (ONL+) and outer segment (OS+) thickness. A linear structure-function model was used to describe the relationship between threshold and the product of ONL+ and OS+ thickness.

Results: For peripheral field measurements, thresholds were generally normal for most subjects with XLRS. All subjects had perifoveal and parafoveal threshold elevations under dark-adapted and high illuminance conditions, with thresholds at moderate illuminances being closer to normal. For foveal measurements, seven of nine subjects with XLRS had normal dark-adapted thresholds, and all had abnormally elevated high illuminance thresholds. Threshold-versus-illuminance curves in the fovea, parafovea, and perifovea were abnormally steep for subjects with XLRS, appearing similar to the normal peripheral field shape. Under both dark- and light-adapted conditions, threshold was predicted by ONL+ × OS+ thickness at nearly all field locations.

Conclusions: Threshold elevation in XLRS is complex, depending on both the adaptation level and the visual field location. The pattern of threshold-versus-illuminance suggests that macular function in XLRS is similar to the periphery of controls.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Dark Adaptation / physiology*
  • Electroretinography
  • Female
  • Fovea Centralis / diagnostic imaging*
  • Fovea Centralis / physiopathology
  • Humans
  • Male
  • Middle Aged
  • Photic Stimulation
  • Retinoschisis / physiopathology*
  • Tomography, Optical Coherence / methods*
  • Visual Acuity*
  • Visual Fields / physiology*
  • Young Adult