To the Editor.
—Previous authors have disagreed on how the blood glucose affects the refractive state of the lens.1,2 The mechanism probably involves a number of factors including the level and speed of cortical and nuclear hydration, the overall lens shape, and the lens position. Definitive experimental data are not yet available. It is interesting to speculate on mechanisms as Keller does in the paper to which he refers, but I am not yet convinced by any "simple explanation."There are many descriptions in the literature of new diabetics who have not been hospitalized or who have been studied from the time of diagnosis.2,3 If pretreatment hyperopia were common, one would expect more reports of it, especially in adults who would be symptomatic. On the other hand, few authors have analyzed early and asymptomatic refractive changes in diabetes, and I agree with Keller that the practitioner should think
Marmor MF. Hyperopia in Diabetes-Reply. Arch Ophthalmol. 1973;90(6):512. doi:10.1001/archopht.1973.01000050512025