Anterior segment changes with age and during accommodation measured with partial coherence interferometry.

PURPOSE

To evaluate anterior segment alterations with age and during accommodation in different age groups.

SETTING

Department of Ophthalmology, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary.

METHODS

Fifty-three subjects (101 normal eyes) were enrolled in this study and divided into 3 age groups: younger than 30 years (Group 1), between 31 years and 44 years (Group 2), and older than 45 years (Group 3). The total amplitude of accommodation was determined with a defocusing technique, and anterior segment measurements were performed by partial coherence interferometry.

RESULTS

Group 1 comprised 32 eyes; Group 2, 37 eyes; and Group 3, 32 eyes. The total amplitude of accommodation decreased with age (P<.0001). With the target position at infinity, the lens thickness (LT) and anterior segment length (ASL) increased and the anterior chamber depth (ACD) decreased significantly with age (P<.0001). During accommodation in the youngest group, the mean change in LT was 36.3 mum/diopter (D) and in ACD, -26.7 mum/D. The mean accommodation-induced ACD change was -0.08 mm +/- 0.06 (SD) in Group 1, -0.064 +/- 0.087 mm in Group 2, and -0.03 +/- 0.06 mm in Group 3 (P = .0004). The mean LT change during near fixation was 0.109 +/- 0.063 mm in Group 1, 0.103 +/- 0.136 mm in Group 2, and 0.006 +/- 0.05 mm in Group 3 (P<.0001). The mean ASL change during accommodation was 0.029 +/- 0.037 mm, 0.039 +/- 0.114 mm, and -0.023 +/- 0.051, respectively (P<.0001).

CONCLUSIONS

In addition to forward movement of the anterior lens surface with age, the posterior surface moved backward. Alterations in LT and ACD sufficient for a unit of refractive power change during accommodation might be smaller than previously thought. Anterior shifting of the lens may also participate in the accommodative response.