Purchase this article with an account.
K.J. Al-Ghoul, W.M. Al-Ghoul, R.K. Zoltoski, J.R. Kuszak; Compaction and Scatter as a Function of Age in Rabbit Lenses . Invest. Ophthalmol. Vis. Sci. 2003;44(13):3485.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: To correlate particular age-related structural changes (specifically compaction of nuclear lens fibers along the visual axis) to the amount of scatter in rabbit lenses. Methods: New Zealand White rabbits at 16-20 months old (adult) and 3.5-4 years old (aged) were utilized for this study. Immediately after sacrifice, scatter was assessed by laser scan analysis using the ScantoxTM In Vitro Assay System. All lenses were scanned at 0°, 45°, 90° and 135° such that the 0° and 90° scans were coincident with respectively, the posterior and anterior line suture planes. Lenses were then fixed, dissected to reveal the embryonic (EN) and fetal (FN) nuclear regions and processed for scanning electron microscopy. Compaction of fibers was assessed by morphometric analysis of the following parameters: the anterio-posterior (A-P) axis length of the EN, the presence of accordion-like compaction folds on EN fibers, the elliptical angles described by FN fibers, and the number of fiber ends in a given length (10µm) along radial cell columns in the FN. Results: Scatter, measured as relative intensity of lasers transmitted through the lens, was significantly greater in aged lenses as compared to adult lenses (p=0.01). In addition, the average length of the A-P axis in the EN was reduced in aged as compared to adult lenses, although the difference was not significant. This finding was consistent with limited compaction folds noted along the length of EN fibers in both age groups. The average elliptical angles described by anterior and posterior portions of inner FN fibers (1mm from the center of the EN) were significantly reduced as a function of age (p=0.04 for anterior; p=0.03 for posterior). The average elliptical angles of outer fetal fibers (2.5mm from the center of the EN) were not significantly different in adult and aged lenses since all lenses examined had comparable angles to inner fetal fibers of aged lenses, i.e. they were all compacted. The number of fiber ends/10µm along radial cell columns in the FN was not significantly different as a function of age. Conclusions: In rabbit lenses, increased scatter appears to be correlated with fiber compaction. The data suggests that age-related compaction in FN fibers precedes compaction in the older EN fibers.
This PDF is available to Subscribers Only