Comparision of Optical Low Coherence Reflectometry Versus Ultrasonic Biometry in High Hypermetropia

To compare anterior chamber depth (ACD), axial length (AL), and lens thickness (LT) measurements obtained by the Lenstar LS 900 (Haag-Streit AG) optical low-coherence reflectometry with those obtained by the A-scan contact ultrasound among patients with moderate and high hypermetropia.

Fifty-two eyes of 52 patients with moderate and high hypermetropia (spherical equivalent of +4 D or more) were examined in this study measurements of ACD, AL, and LT obtained by Lenstar were compared with those obtained by applanation A-scan ultrasound. All measurements were obtained by two independent examiners. The interdevice agreements were evaluated with Bland-Altman analyses.

The mean age of the patients was 54.78±12.77 years (range 18-74 years). The mean spherical equivalent refractive power was +5.16±1.12 D (+4.0 to +8.75). The mean values of ACD, AL, and LT with A-scan were 3.05±0.34, 21.55±0.75, and 4.33±0.49 mm, respectively, whereas these values were 2.99±0.45, 21.58±0.78, and 4.20±0.44 mm, respectively, with Lenstar. There was statistically significant difference of LT between the two methods (P=0.02). The mean differences (lower/upper limit of agreement) of the ACD, AL, and LT values for A-scan ultrasound and Lenstar were -0.06 (-0.594/0.474), 0.04 (-0.380/0.459), and -0.12 (-0.739/0.502), respectively.

Among patients with moderate and high hypermetropia, the biometric measurements of ACD, AL, and LT by ultrasound and optical biometry were determined to be correlated and there was a high degree of agreement between contact A-scan ultrasonic biometry and Lenstar.