Changes in the state of water in senile cataractous lenses as studied by nuclear magnetic resonance

Abstract

Measurements of NMR relaxation times T 1 and T 1 ϱ are presented for water protons in normal human, porcine and senile cataractous lenses, together with determinations of both total water content and the fraction of bound water. Relaxation times measured in completely opaque cortical cataractous lenses are longer than for normal lenses at temperatures above the freezing point of the free water, the difference being most marked in the case of spin-lattice relaxation in the rotating frame ( T 1 ϱ ). The changes reflect a reduction in the proportion of bound water. No such changes were observed in lenses affected only by nuclear cataract, which appear to retain a normal water balance.