Abstract
On comparing micropneumographical and radiographical features with histological data the empty spaces observed in the auditory ossicles result mainly in medullary cavities and to a lesser extent in intraosseal vessels. Consequently it may be deduced that the impressions obtained by osteo-micropneumography, a new histological technique described in the article, and radiographic enlargement indicate not only the intrinsic bone structure but especially the vasculo-medullary distribution. From this point of view it seems that the lacunar phase corresponds to a mainly sinusoidal blood supply in the medullary spaces whereas the canalicular phase corresponds to a vascular type of distribution. Therefore from the morphological features observed in radiographs and micropneumographs an estimation of the blood supply in the ossicles can be made in physiological conditions according to the age of the subject.