Measurement of Crystalline Lens Volume During Accommodation in a Lens Stretcher

Abstract

Lens volume remains effectively constant during accommodation, with changes that are less than 1% on average. This result supports a hypothesis that the change in lens shape with accommodation is accompanied by a redistribution of tissue within the capsular bag without significant compression of the lens contents or fluid exchange through the capsule.

Optical Coherence Tomography Based Estimates of Crystalline Lens Volume, Equatorial Diameter, and Plane Position

“…In the accommodating eyes, we found that VOL remained constant with accommodation, DIA decreased and EPP shifted backwards, which is consistent with previously reported results by Hermans et al, 26 and Marussich et al 9 However, Gerometta et al 66 measured an increase of lens VOL with accommodation.…”

“…These results are in agreement with recent studies that reveal the relevance of lens surface astigmatism 3,27 and errors associated to the assumption of lens rotational symmetry. 9 The proposed approach could be implemented in current commercial devices such as Scheimpflug-imaging based systems or clinical anterior segment OCT. Nevertheless, as demonstrated before, distortion correction is critical to obtain accurate results.…”

“…However, in vivo OCT measurements of the posterior lens surface were obtained through the anterior surface, assuming a homogeneous refractive index in the optical distortion correction. Marussich et al 9 showed that an uncertainty of 60.01 in the refractive index produced an uncertainty on the order of 61% in the lens VOL and suggested that ignoring the GRIN introduced a negligible error. Siedlecki et al 69 showed that GRIN did not affect significantly the estimation of lens radii of curvature, although posterior lens asphericity estimates may in fact be affected by neglecting the presence of GRIN.…”

The effects of mechanical strain on mouse eye lens capsule and cellular microstructure

“…The complete recovery of fiber width is consistent with bulk lens equatorial recovery, which was also complete at 6%, and nearly complete at 9% equatorial strain. Since 9% equatorial strain is already beyond the physiological equatorial strain that accommodative lenses would experience in vivo (Jackson, 1907;Marussich et al, 2015), we did not examine the effect higher loads to determine whether greater equatorial strains led to incomplete recovery.…”

“…Our data shows that compression with 10% axial strain in mouse lenses does not cause irreversible damage to bulk lens shape. Ten percent axial strain is within the range of physiological primate lens shape changes during accommodation calculated from in vivo measurements (Jackson, 1907;Doyle et al, 2013;Marussich et al, 2015). Thus, for the rest of this study, we focused primarily on the microstructural changes that occur at 10% axial strain.…”