Abstract O'Donnell C et al.

Correlations between refractive error and biometric parameters in human eyes using the LenStar 900.

O'Donnell C, Hartwig A, Radhakrishnan H.
Cont Lens Anterior Eye. 2011 Feb;34(1):26-31.

PURPOSE:
To investigate the relationship between refractive error and ocular biometry in healthy subjects using a new optical low coherence reflectometry device.

METHODS:
Biometric measurements were obtained with a LenStar LS 900 (Haag Streit, Switzerland) on one eye of 70 phakic subjects (mean±SD age; 29±9 years). Forty myopes and 30 non-myopes (best sphere range -9.63D to +0.63D) were included. Outcome measures were compared for the two groups using one way between groups ANOVA. These included; keratometry, central corneal thickness, iris width, anterior chamber depth, pupil diameter, lens thickness, axial length and retinal thickness. No mydriatic or cycloplegic agents were used.

RESULTS:
There were significant differences between groups for keratometry readings (p=0.021 and p=0.038 for steep and flat k readings respectively), anterior chamber depth (p=0.001), lens thickness (p=0.026) and axial length (p<0.001). As expected significant correlations were found between spherical equivalent power and axial length (Pearson product-moment correlation r=-0.75, p<0.001) and between spherical equivalent power and anterior chamber depth (r=-0.29, p=0.018). Anterior chamber depth and pupil diameter decreased with age (r=-0.429, p<0.001 and r=-0.386, p=0.001 respectively) whereas lens thickness increased with age (r=0.618, p<0.001).

CONCLUSIONS:
Our data showed significant differences between myopes and non-myopes for the key biometric parameters assessed and provides information about the relationships between these biometric parameters and age. The results, coupled with a unique ability to image and analyse the ocular structures non-invasively make the LenStar a promising new instrument for ocular evaluation in research and clinical practice.