From Big Medical Encyclopedia

ULYTKOVY TUBULE [canaliculus cochleae (PNA, JNA, BN A); synonym: a tubule of a snail, a water supply system

of a snail] — the tubule of a funneled form in a stony part of a temporal bone connecting perilymphangeal space of an inner ear with a subarachnoid space of a brain. Length of a tubule is 7 — 17 mm. Its outside (lower) opening to dia.

2 — 6 mm are on the rear edge of a pyramid of a temporal bone under an internal acoustical opening (see the Skull), and internal (upper) diazd. to 0,3 microns — approaches initial department of the main curl of a snail, approximately in the center of a pyramid (fig).

There was an opinion that in At. to. there is a feather a lymphatic channel. However numerous researches showed that At. to. it is in most cases executed friable with about e d both and and ate t, Kommersant of N about and fabric (see), rich with the collagenic fibers forming network, in loops a cut there are cellular elements. It is impossible to exclude participations At. to. in exchange between a perilympha and cerebrospinal liquid (see). When At. to. zarashchen, communication of perilymphangeal space of an inner ear (see) with a subarachnoid space of a brain (see M ozgovy covers) the hl is carried out. obr. through perivascular and perineural spaces of the vessels and nerves which are in internal acoustical pass.

In most cases near At. to. there are one or two to -

Fig. The diagrammatic representation of topography of a cochlear tubule on a cut of a temporal bone: 1 — a labyrinth; 2 — a drum cavity with acoustical stones; z — outside acoustical pass; 4 — an internal jugular vein; 5 — an upper bulb of an internal jugular vein; 6 — an internal carotid artery; 7 — additional tubules of a cochlear tubule; 8 — the glossopalatine, wandering and additional nerves; 9 — a cochlear tubule; 10 — internal acoustical pass with the eighth cranial nerve which is in it.

stno-venous — so-called additional a tubule At. to. In each of them there passes the vein (at. canaliculi cochleae), through to-ruyu a part of blood from vessels of an inner ear streams directly in the lower stony sine (see the Meninx). In the absence of these tubules venous outflow is carried out through veins of a labyrinth and a vein of a water supply system of a threshold (at. aquaeductus vestibuli).

Existence of communication of a cavity of a labyrinth with a subarachnoid space of a brain through At. to. (and other ways) allows to use a spinal puncture (see) with the diagnostic and medical purposes at nek-ry diseases of an inner ear. So, at inflammatory diseases of a labyrinth changes of cerebrospinal liquid can be noted (a pleocytosis, change of a ratio of protein fractions, etc.). The spinal puncture can be used for the purpose of decrease in labyrinth pressure, and also for introduction to a subarachnoid space of pharmaceuticals for immediate effect on patol. the center in an inner ear. Through At. to. to adjacent areas contagiums at a labyrinthitis can extend (see) or meningitis (see). As near the lower opening At. to. there pass trunks of the glossopalatine, wandering and additional nerves, patol. processes in the field cause dysfunction of these nerves (see. Vagus nerve, Dobavochn y nerve. Glossopharyngeal nerve). Disturbance of an integrity of a thin bone partition between At. to. and an upper bulb of an internal jugular vein at operative measures can lead to infection of an inner ear and a subarachnoid space, and also to injury of the above-stated nerves.

Bibliography: And in and with about in P. B. Water pro-

waters of a snail and its additional tubules at the person (a topografo-anatompchesky research), Vestie, otorinolar., No. 4, page 19, 1058; M e u of m a n Y. Zur Anato-mie des Aqueductus cochleae nebst einigen Bemerkungen uber dessen Physiologie, Acta Soc. Med. «Duodecim», Bd 13, S. 1, 1930.

11. B. Abiicob.