Saving eyesight after mid-life

In spite of the fact that much of it is preventable, practically no organized effort has been made to curb the blindness from degenerative disease which comes after the fortieth year. While it is not possible with the present state of knowledge to prevent the degenerations that come with age, it has been repeatedly shown possible to prevent the damage to sight through early recognition and early treatment, notably in glaucoma which leads all other causes of blindness after mid-life. - p. 15-16.