FISSULA ANTE FENESTRAM: ITS FORM AND CONTENTS IN EARLY LIFE

The fissula ante fenestram has come to be regarded as a constant feature of the human ear and is believed to occur typically as a channel within the bone containing an avascular connective tissue. In early corrosion preparations described by Hyrtl¹in 1845 and by Siebenmann²in 1890 only the medial end of the fissula was demonstrated, and in their figures it appears as a macroscopic projection of the anterior portion of the vestibule. Later, Mayer³(1917) and others have described and figured the full structure with its termination on the wall of the tympanic cavity. They have emphasized that it is a fissure-like band of connective tissue within bone, and, because of its location between the cochlear and the canalicular portion of the capsule, they have maintained that it serves as a synchondrosis between them, absorbing the strains incident to growth. From a study