A renewed interest has recently been manifest in the biochemical factors bearing on otosclerosis. At the meeting of the German Otolaryngologic Congress in 1932, and previously, at the meeting of the Southwest Society of German Otolaryngologists, Grahe and Griebel1 reported a series of experiments with the blood serum of known otosclerotic patients on ground up bone of the labyrinth, which gave up its calcium and phosphorus to a greater degree than when exposed to normal serum. They attributed this to the action of a ferment on the order of a phosphatase in the blood of otosclerotic persons.
At the 1933 congress of German otolaryngologists, Krainze2 reported experiments on rabbits with artificially induced acidosis, resulting in increased porosity of the labyrinthine bone and deposition of uncalcified bone and also general rachitic-like changes in the skeleton.
Barth,3 using parathyroid extract in rats and guinea-pigs, reported changes in the labyrinth