ELECTRON MICROSCOPIC STUDIES OF OTOSCLEROTIC FOCUS

From electron microscopic studies of otosclerotic tissue fixed immediately after surgical removal of the stapes, we feel we can deduce the following: First: Apart from the borderline between focus and normal tissue as seen in the light microscope, there are 'microfoci' demonstrable only in the electron microscope. The focus appears to enlarge by fusion of these microfoci. Second: Osteoclasts appear to play a subordinate role during the so-called phase of resorption. On the other hand, we demonstrated pronounced osteocytic resorption, pericellular lysis of collagen being an invariable finding. In relation to these findings, lyso-sonies were often observed in the osteocytes. The endothelial cells of the capillary network appeared to be normal. © 1969 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.