[Cataract-related changes of intelligence. An innovative aspect].

Background: On average, the intelligence level of adults decreases with age. Since loss of vision increases in parallel and, according to a review of literature, impairment of vision corresponds to cognitive deterioration, age-related reduction of intelligence could partially be explained by restricted vision.

Question: Are late-acquired cataracts closely related to reduction in intelligence levels? AIM. If it is substantiated that late-acquired cataracts cause mental impairment, a frequent disorder of vision will be identified that principally may be treated quickly and successfully. By this means ophthalmologists were able to improve intelligence, "the" key variable in modern information societies.

Methods: An open controlled longitudinal study in five samples of seniors with and without cataract surgery.

Results: The actual mental efficiency and the knowledge of cataract patients reached a lower level than a "normal" population. A few weeks after an IOL implantation the actual intelligence level increased relevantly and statistically significantly in all samples, whereas controls displayed no systematic changes.

Conclusion: Cataracts and removal by surgery can change the IQ considerably which is of great importance for the patient and for the social and medical environment.