The metabolism of the lens under normal and pathological conditions has been studied extensively, and various factors which produce opacities of the lens are known. The changes leading to senile cataract in human beings are not understood, however (for review of the literature see Bellows,2 Friedenwald et al.,5 and Nordmann15).
The lens does not have its own blood supply and is, for its nutrition, dependent on the aqueous humor. It seems reasonable to assume that changes in flow or composition of the aqueous humor can produce changes in the normal metabolism of the lens, leading to opacities. An investigation of the rate of aqueous flow with a comparison between normal human eyes and eyes with cataract would, therefore, be of interest.
Different methods for determining the rate of aqueous flow in human eyes have been developed. The tonographic method shows an uncertainty in the estimate of aqueous
LINNÉR E. The Rate of Aqueous Flow in Human Eyes With and Without Senile CataractA Study by Means of the Suction-Cup Method. AMA Arch Ophthalmol. 1959;61(4):520-527. doi:10.1001/archopht.1959.00940090522003