Change in Axial Length in Highly Myopic Adults Using Partial Coherence Interferometry

ABSTRACT

PURPOSE: To investigate the change in axial length (AL) in highly myopic adults using partial coherence interferometry, and to identify the factors associated with the increase in AL. METHODS: Medical records of highly myopic adults (≥ −6 diopters [D] or AL ≥ 26.0 mm) were retrospectively reviewed. The AL of each patient was measured using partial coherence interferometry at least three times over 2 years, and the yearly change in AL was calculated. Associations between age, AL, choroidal thickness, and the rate of AL change were evaluated using multiple regression analysis. RESULTS: In total, 24 patients (4 males, 20 females) and 44 eyes were included in this study. The mean age was 54.9 ± 10.4 years, the initial AL was 29.335 ± 2.006 mm, the choroidal thickness was 72.7 ± 41.80 µm, the average spherical equivalent was −11.86 ± 3.85 D (−5.1~−22.0 D), and the mean follow-up period was 2.2 ± 0.5 years. A significant increase in AL of ≥0.05 mm was observed in 38 eyes (86.4%) at 2 years. The mean AL was significantly increased, to 29.409 ± 2.007 mm (p < 0.001), at 1 year and to 29.476 ± 2.028 mm (p < 0.001) at 2 years. The average rate of AL change was 0.071 ± 0.049 mm (−0.01~0.19 mm) per year. None of the included factors showed an association with the rate of AL change in multiple regression analysis. CONCLUSIONS: In this study, an increase in AL in highly myopic adults was more frequent than in previous reports using A-scan. Periodic measurements are therefore recommended for the early detection of complications.