Cataract surgery rates have soared 10-fold over the past 40 years in England, according to new research.
The increase has led doctors to question whether the surgery is now undertaken too readily in some NHS cases.
National data on hospital admissions for cataract surgery in England from 1968 to 2004 were analysed by researchers from the Oxford Eye Hospital and Oxford University.
Admission rates in England rose from 62 per 100,000 people in 1968, to 173 in 1989, and then to 637 in 2004.
Wide regional variations in admissions were also found in the study published in the British Journal of Ophthalmology.
The highest rates tend to be in more deprived areas.
The report says: "The fact that there is substantial geographical variation in cataract surgery raises similar questions as to whether areas with high rates are 'overservicing' in relation to need or whether areas with low rates are 'underproviding' care."
The push to provide more cataract surgery was kick-started in the 1990s when experts predicted a major shortfall in provision, made worse by an ageing population.