IN A PREVIOUS paper by one of us (E. E.),1 it was suggested that the long incubation period in silica granuloma was basically due to physical factors. These included the very slow solution of glass, sand or other silicon-containing material by the tissue fluids. This resulted in the deposition of silicon dioxide in the tissue and in the washing away of soluble salts by the circulation. A sarcoid reaction did not develop until sufficient free silica had been deposited in the tissue.
This would presuppose a pregranuloma stage when the silica was being deposited in the tissues. This stage has not been reported previously. Therefore, the following two cases are presented.
REPORT OF CASES
Case 1.—E. D. B., 47-year-old Negro man, consulted one of us on May 27, 1954. Three months previously he had been hit on the forehead with a beer bottle at a party.