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Keratoconus and Visual Performance with Different Contact Lenses.

Ana Marta1,2, João Heitor Marques1, Daniel Almeida1

  • 1Department of Ophthalmology, Centro Hospitalar Universitário do Porto (CHUPorto), Oporto, Portugal.

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|December 24, 2021
PubMed
Summary

Rigid gas permeable contact lenses (RGPCL) offer superior visual quality in keratoconus patients compared to other lens types, despite underlying corneal irregularities. This study highlights RGPCL as a key option for improving vision in these individuals.

Keywords:
contact lenskeratoconusoptical qualityvisual performance

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Area of Science:

  • Ophthalmology
  • Optometry
  • Biomedical Engineering

Background:

  • Keratoconus is a progressive corneal ectasia affecting visual acuity.
  • Contact lenses (CL) are essential for correcting vision in keratoconus patients.
  • Different CL materials and designs may impact visual performance differently.

Purpose of the Study:

  • To analyze and compare visual performance in keratoconus patients wearing different types of contact lenses (CL).
  • To evaluate the relationship between corneal tomography parameters and visual quality with CL wear.

Main Methods:

  • Retrospective study of 96 eyes from 59 keratoconus patients.
  • Evaluation of best-corrected visual acuity (BCVA) with CL and spectacles.
  • Assessment of contrast sensitivity (CS), light scattering (OSI), and vision break-up time using specialized devices.
  • Corneal tomography performed using Oculus Pentacam® HR.

Main Results:

  • Rigid gas permeable contact lenses (RGPCL) showed better dynamic objective scatter index (OSI) compared to hydrogel/silicone hydrogel contact lenses (HGCL).
  • Hybrid contact lenses (HCL) demonstrated better mean contrast sensitivity (CS) in photopic conditions than HGCL.
  • RGPCL wearers had more severe keratoconus indicators (higher mean K, lower thinnest point corneal thickness) but superior dynamic visual quality.

Conclusions:

  • Visual quality significantly differs among various contact lens types in keratoconus.
  • Despite more challenging corneal topography, RGPCL are associated with better dynamic visual quality.
  • Contact lens selection plays a crucial role in optimizing visual function for keratoconus patients.