Comparision of optical low coherence reflectometry versus ultrasonic biometry in high hypermetropia

Abstract

Purpose: 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. Methods: 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. Results: 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. Conclusion: 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.