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.

PURPOSE.To quantify the role of anterior zonular tension on the optomechanical lens response during simulation of accommodation in primates. METHODS. Postmortem cynomolgus monkey eyes (n ϭ 14; age range, 3.0 -11.5 years) were dissected leaving intact the lens, zonules, ciliary body, hyaloid membrane, anterior vitreous, and a scleral rim. The lens was mounted in a lens-stretching system and stretched radially in step-wise fashion. The load, and the lens diameter and power were measured at each step and the diameter-and power-load relationships were quantified. The anterior zonular fibers were then transected, and the experiment was repeated. The equatorial lens diameter and lens optical power before and after zonular transection were compared. RESULTS. Stretching increased the lens diameter by 0.25 Ϯ 0.09 mm (median Ϯ interquartile range) before and 0.25 Ϯ 0.19 mm after zonular transection. Stretching decreased the lens power by 13.0 Ϯ 6.5 D before and 10.6 Ϯ 8.0 D after zonular transection. The load required to change the diameter of the lens by 1 mm decreased from 18.8 Ϯ 10.7 g before to 15.0 Ϯ 7.8 g after zonular transection. The absolute change in power per gram of loading decreased from 2.5 Ϯ 1.1 before to 2.0 Ϯ 1.2 D after zonular transection. CONCLUSIONS.The cynomolgus monkey lens retains a significant fraction of its accommodative ability after transection of the anterior zonules in simulated accommodation experiments.

While either the anterior or posterior zonules alone are capable of changing the shape of both lens surfaces, the anterior zonules have a greater effect on the anterior lens surface, and the posterior zonules have a greater effect on the posterior lens surface.

Laser trabeculoplasty (LT) is a commonly used modality of treatment for glaucoma. The mechanism by which LT lowers the intraocular pressure (IOP) is unknown. Using cat eyes, selective laser trabeculoplasty (SLT) with a Q-switched frequency doubled Nd:YAG laser was used to treat the trabecular meshwork (TM). Laser treated TM was then subjected to proteomic analysis for detection of molecular changes and histological analysis for the detection of structural and protein expression patterns. In addition, the protein glycosylation patterns of laser treated and non-treated TM was assessed and differentially glycosylated proteins were proteomically identified. SLT laser treatment to the TM resulted in elevated glycosylation levels compared to non-lasered TM. TM laser treatment also resulted in protein expression levels changes of several proteins. Elevated levels of biglycan, keratocan and prolargin were detected in laser treated TM compared to non-lasered controls. Further investigation is anticipated to provide insight into how glycosylation changes affect TM proteins and TM regulation of aqueous outflow in response to laser trabeculoplasty.