Higher Order Wavefront Aberrations in Early Keratoconus and Keratoconus Suspects

Abstract

 

Abstract:

 

To determine whether higher order aberrations detected with the ALCON

 

LADARWAVE wavefront sensor can be used to distinguish ‘early’ keratoconus and

 

keratoconus ‘suspects’ from a normal control group.

 

We studied 52 normal controls, 12 patients with ‘early’ keratoconus and 11 keratoconus ‘suspects’ with videokeratography (TMS–1, Tomey) and aberrometry (LADARWAVE,Alcon). Videokeratography patterns and Zernike polynomials were analyzed for each patient. Data were compared and analyzed to determine whether specific higher order aberrations could be identified to separate ‘early’ keratoconus and keratoconus ‘suspects’ from normal controls.

 

see Table

 

 

^{*: F–test for data with normal distribution; Wilcoxon test for data without normal distribution.}

 

Vertical coma, secondary astigmatism, and total RMS coma appear to be useful in distinguishing ‘early’ keratoconus and keratoconus ‘suspects’ from normal controls. Vertical coma, in particular, has the most potential for differentiating these groups based on aberrometry alone. Our findings are consistent with previous work by Maeda et al. (Ophthalmology. 2002 Nov;109(11):1996–2003). In this paper, they determined that spherical and coma–like aberrations were increased in keratoconus compared to normal. To our knowledge, our analysis is the first to compare aberrometry between normals and keratoconus, as well as keratoconus ‘suspects’. Our analysis also determines specifically the significance of vertical coma in kertoconus and keratoconus suspects.

 

 

Keywords: keratoconus • optical properties • clinical (human) or epidemiologic studies: risk factor assessment