Wavefront analysis in eyes with nuclear or cortical cataract.

Area of Science:

• Ophthalmology
• Optics
• Vision Science

Background:

• Cataracts, particularly nuclear and cortical types, can affect visual function.
• Higher-order aberrations (HOAs) contribute to reduced image quality beyond refractive error.
• Wavefront analysis offers a method to quantify ocular aberrations.

Purpose of the Study:

• To compare ocular and corneal higher-order aberrations in mild cataracts.
• To assess the impact of ocular HOAs on contrast sensitivity loss.
• To investigate the relationship between lens density and HOAs.

Main Methods:

• Observational case series involving patients with mild nuclear/cortical cataracts and normal subjects.
• Wavefront aberrations of the whole eye (oculus) and cornea measured using Hartmann-Shack aberrometry.
• Calculation of HOAs using Zernike polynomials; analysis of contrast sensitivity and average lens density.

Main Results:

• Ocular HOAs were significantly higher in cataractous eyes compared to normal eyes.
• Corneal HOAs did not differ significantly between groups.
• Spherical aberration polarity differed between nuclear (negative) and cortical (positive) cataracts.
• Contrast sensitivity strongly correlated with ocular HOAs and moderately with average lens density.

Conclusions:

• The Hartmann-Shack aberrometer is effective for evaluating image quality in mild cataracts.
• Distinct spherical aberration patterns exist for nuclear versus cortical cataracts.
• Lens optical aberrations, alongside light scattering, contribute to reduced contrast sensitivity in early cataracts.