A Study in the Comparative Anatomy of the Blood-vascular System of the Internal Ear in Mammalia and in Homo (Japanese)

Abstract

(I) There is no artery which is called A. auditiva interna as described in the general text- and hand-books of anatomy or of otology.(2) A. auditiva of Siebenmann is surely a misconception of A. cerebelli inferior anterior.(3) The labyrinthine artery is given off always from A. eerebelli inferior anterior, and it is of two kinds, namely, A. labyrinthica and Aa. labyrinthicae, as in the ear of the monkey.(4) The main branches of the labyrinthine artery- namely A. labyrinthica and also Aa. labyrinthicae - are classified into these two types ;_??_A. cochleae (or A. vestibulo-cochlearis) of the second type is a union of A. vestibulo-cochlearis with A. cochleae propria, lacking the stem of the latter in the meatus acusticus internus, of the first type.(5) A. utricularis is always a branch of A. vestibuli anterior.(6) A. nervi ampullaris posterioris of Siebenmann has no relation to the blood-vascular supply of the ampulla membranacea posterior, especially, on its crista ampullae.(7) A. saccularis is a branch of R. vestibularis of A. vestibulocochlearis or A. cochleae (second type) in the labyrinth. It is never given off from the trunk of A. vestibulo-cochlearis in the meatus acuternus internus, contrary to Siebenmann's staterneut.(8) R. vestibularis of A. vestibulo-cochleae or of A. cochleae gives off some branches on a part of the cochlea, i. e., the scala vestibuli, the lamina spiralis, and the ganglion spirale of the vestibular portion of the basal winding.(9) There are two main venous trunks of the blood-vascular system of the membranous labyrinth as follows:i. V. canaliculi cochleaeii. V. aquaeductus vestibuli(10) V. canaliculi cochleae is so extremely powerful, that it collects all the tributaries of the whole cochlea and about a half of the vestibule. It has, therefore, the following branches ;a) V. spiralis anteriorb) V. spiralis posteriorc) V. vestibuli anteriord) V. vestibuli posterior(11) V. aquaeductus vestibuli occupies only the tributaries of all the semicircular canals and of about a half of the vestibule.(12) The trunks of the main branches of V. canaliculi cochleae in the cochlea have four kinds of serial twigs as follows:a) Vv. radiatae scalae vestibulib) Vv. radiatae laminae spiralisc) Vv. radiatae scalae tympanid) Vv. ganglionum spiralium(13) The venous system of the membranous labyrinth has two types in the cochlea as follows:i. The first kind shows that most of the tributaries in the cochlea are received by V. spiralis posterior.ii. The second kind shows that most of the tributaries in the cochlea are collected by V. spiralis anterior.(14) V. vestibuli posterior receives, without fail, some venous twigs of the lamina spiralis on the proximal end of the basal winding, while it is a somewhat powerful branch on the posterior portion of the vestibule.