The constantly increasing therapeutic use of magnesium salts, particularly in the United States, makes one consider whether or not harmful effects on the eye can be produced. Burge1 had shown that the magnesium content of cataracts removed in this country was five times that of cataracts removed in India.
The possibility of a relation of intake of magnesium to pathologic changes in the lens was suggested by the following case:
R. K., a housewife aged 49, was first seen on Dec. 4, 1935, complaining of failing vision in each eye for the past year.
Examination disclosed soft mature cataracts, with good light projection. A search into all possible etiologic factors, which were present at the time or which may have existed in the formative period, failed to disclose any of a dietary, hereditary, metabolic, endocrinologic or toxic nature.
Three years previously, at a time when from the patient's