What is the Inner Ear?

The inner ear includes labyrinth of bone and labyrinth of membrane, which is contained in the bone of the temporal bone rock, located between the tympanum and the base of the inner ear canal.

The inner ear includes labyrinth of bone and labyrinth of membrane, which is contained in the bone of the temporal bone rock, located between the tympanum and the base of the inner ear canal.

Chinese name

inner ear

Foreign name

internal ear

Alias

get lost

Attributes

Hearing system components

Location

Between the tympanum and the bottom of the inner ear canal

Constitute

Bone labyrinth and membrane labyrinth

Inner ear anatomy

1. Bone labyrinth is a series of curved tubules and cavities surrounded by dense bone, which is about 1.7 to 2 cm long, and its long axis is roughly consistent with the long axis of the temporal bone. Membrane labyrinth is a membrane tubule and sac composed of epithelium and connective tissue, which is similar to bone labyrinth.

2. Membrane labyrinth has bit and hearing sensor. Membrane labyrinth is filled with internal lymph, and between the membrane labyrinth and the bone labyrinth wall is filled with external lymph. There is no direct communication between internal and external lymph.

Bone labyrinth is divided into vestibular, semicircular canal and cochlea. In addition, the vestibular snail nerve passes through the inner ear canal, so it is also attached to the bone labyrinth description.

Vestibule: The vestibule is an approximately elliptical cavity in the middle of the labyrinth of bone. It communicates forward and downward with the cochlea; backwards with three bone semicircular canals. The outer wall is a part of the inner wall of the tympanum, and is connected to the base of the sacrum at the vestibular window; the inner wall corresponds to the inner ear canal floor. The vestibular wall has oblique vestibules. The posterior upper part of the palate is an oval capsule recess, and the anterior lower part is a balloon recess, each containing a labyrinth of the same name. The lower part of the iliac crest separates to form a smaller volute recess, which houses the blind vestibular end of the volute. There are several groups of small holes on the inner wall, called ethmoidal plaques, which are the channels of the vestibular nerve. The lower part of the crypt of the oval capsule also has the vestibular aqueduct inner opening, which is where the endolymphatic vessels enter the vestibular aqueduct.

Bone semicircular canal: Bone semicircular canal includes three anterior, outer and posterior canal semicircular canals, all of which are "C" shaped, about 2/3 of the circumference. Each bone semicircular canal is connected to the vestibule with two bone feet. One leg is called ampulla, and each of the three tubes has an enlarged bone ampulla. The other one of the anterior and posterior semicircular canals is called the common bone foot. Single bone foot, so three semicircular canals have a total of five openings in the vestibule. The three bone semicircular canals are perpendicular to each other in space. The anterior semicircular canal arch is upward, perpendicular to the long axis of the cone, and buried in the arch-shaped raised surface; the horizontal arch of the external canal semicircular canal extends backward to form the outer semicircular canal at the entrance of the mastoid sinus; Parallel to the major axis of the cone. The diameter of the bone semicircular canal is about 0.8 to 1.0 mm, and the ampulla doubles.

Cochlea: The cochlea is shaped like a volute, and the cochlea corresponds to the bottom of the inner ear canal. Through the bottom and top is a conical snail shaft composed of bone cancellous, with snail nerves and blood vessels passing through it. The cochlea is a spiral bone tube that curls 21/2 23/4 circles around the snail axis, which is called a spiral tube. The bottom circle of the tube is close to the inner wall of the middle ear and participates in forming the cape; the top circle is finally blind. The bone spiral plate protruding from the snail shaft protrudes into the spiral canal, and the tube is not completely separated into the anterior lateral vestibular step and the posterior medial drum step.

Inner ear canal: It is a short tube in the posterior part of the temporal bone rock. One end is open behind the rock and the other end is finally at the bottom of the inner ear canal. This base is divided into two parts by a horizontal bar. The upper anterior segment is the facial nerve region, with a facial neural tube entrance; the posterior segment has a group of small holes, called the superior vestibular region, through which the ampullary nerve of the oval capsule passes; That is, the spiral hole line, the snail nerve passes; there is a group of small holes in the lower posterior area called the inferior vestibular area, the balloon nerve passes; there is also a large single hole backward, the posterior ampulla nerve passes.

Membrane semicircular canal: The lumen of the membranous semicircular canal is about 1/4 of the bone canal. Corresponding to the canal semicircular canal, it is divided into anterior, lateral, and posterior membranous canals. Each ampullary foot has anterior, outer, and posterior ampulla, which are almost full of the bone cavity, with small peak-like ridges in the lateral position. The ampulla is composed of two kinds of epithelial cells, namely support cells and hair cells. The hairs of the cells are inserted into a glial layer called the ampulla. The ampulla is a sensory sensory receptor that receives rotational variable-speed motion stimulation.