Optomechanical Response of Human Lenses Refilled With Polymer Gel

Abstract

Purpose: : To evaluate the optomechanical response of the human lenses before and after lens refilling.

Methods: : Thirteen post-mortem (40.4±17.1 hours) eyes from eight human donors (30.1±12.8 y/o, range 14-50 y/o) were dissected leaving intact the lens, zonules, ciliary body, hyaloid membrane, anterior vitreous and a segmented scleral rim. The lens preparation was mounted in a lens stretching system and the sclera was stretched 2 mm radially in a step-wise fashion (0.25 mm/step). The load and the lens and ciliary body diameter and lens power were measured at each step. The lens contents were removed and the capsular bag was filled with a flexible polymer gel. The changes in the lens and ciliary body diameter and the lens power, and load relationships were compared before and after refilling.

Results: : The lens diameter, ciliary body diameter, power, and the changes in lens diameter and power all increased after lens refilling, from 9.01±0.41 mm to 9.05±0.48 mm (p = 0.030), 11.38±0.61 mm to 11.51±0.95 mm (p = 0.033), 21.79±2.72 D to 25.79±3.49 D (p = 0.017), 0.27±0.08 mm to 0.42±0.05 mm (p < 0.001) and 2.51±1.81 D to 4.78±2.07 D (p = 0.008) respectively. The maximum stretching force decreased after lens refilling from 8.93±1.17 g to 7.80±0.70 g (p = 0.006).

Conclusions: : Lens refilling can produce a significant increase in the change in lens diameter and optical power in human lenses.Acknowledgement: Scientific support from Drs. Pravin K Vaddavalli¹, Virender Sangwan¹ and Jean-Marie Parel^2,3,6

Keywords: accommodation • cataract • ciliary body