Vestibulocochlear Organ ---- 前庭蜗器

The Vestibulocochlear Organ 前庭蜗器

   Parts: external ear 外耳 middle ear 中耳 internal ear 内耳：

Conduct the sound wave 。

Contains the receptors of auditory and vestibular organs

External ear

The external ear consists of

auricle 耳廓 ,external acoustic meatus 外耳道 tympanic membrane 鼓膜 .

External ear

1. Auricle 耳廓 Helix 耳轮Antihelix 对耳轮crura of antihelix 对耳轮脚triangular fossa 三角窝Scapha 耳舟auricular concha 耳甲 externalacoustic pore 外耳门Tragus 耳屏，Antitragus 对耳屏auricular lobule 耳垂

2. external acoustic meatus 外耳道 :

bony part 骨部： medial 2/3

cartilaginous part 软骨部： lateral 1/3

External ear

External ear

3. tympanic membrane 鼓膜 :

Flaccid part 松弛部 : upper 1/4

Tense part 紧张部 : lower 3/4

Umbo of tympanic membrance

Cone of light 光锥

鼓膜脐

Consists of three parts Tympanic cavity 鼓室 Auditory tube 咽鼓管 Mastoid antrum 乳突窦 and mastoid cells 乳突小房

Middle ear 中耳

Position: An irregular air-filled cavity locates within the temporal bone, and lies between the tympanic membrane and the lateral wall of the inner ear 内耳 .

• It contains the auditory ossicles 听小骨 , ligaments, muscles, vessels and nerves.

Tympanic cavity 鼓室

Middle ear 中耳 Boundaries:

   (1) Roof or tegmental wall 鼓室盖 :

   (2) inferior wall or jugular wall 颈静脉壁 : separates the cavity from superior bulb of internal jugular v.

   

(3) Anterior wall or carotid wall 颈动脉壁 :

Upper opening for tensor tympani m.

lower opening for auditory tube 咽鼓管鼓室口(4) Posterior wall or mastoid wall 乳突壁 :

Aditus of mastoid antrum: 乳突窦的入口； Pyramidal eminence 锥隆起： 内藏镫骨肌 .

Tympanic cavity 鼓室

   (5) lateral wall or membranous wall 鼓膜壁 :is formed by

tympanic membrane

epitympanic recess 鼓室上隐窝

Middle ear

   (6) Medial wall or labyrinthine wall 迷路壁 : promontory 岬 Fenestra vestibuli 前庭窗 Fenestra cochleae 蜗窗 : covered by secondary tympanic membrane

第二鼓膜 .

Middle ear

Prominence of facial canal 面神经管凸 :

2. Auditory tube 咽鼓管 :     

Middle ear

In childhood: shorter, wider and more horizontal than in adult

Bony part 骨部 : posterolateral 1/3 ,open into the anterior wall of

tympanic cavity

Cartilaginous part 软骨部 : anteromedial 2/3, open into the nasopharynx 鼻咽部

3. Mastoid antrum 乳突窦 and mastoid cells 乳突小房    

Middle ear

mastoid cells

2 ） content of tympanic cavity

(1)auditory ossicles 听小骨： 3 块

malleus 锤骨

incus 砧骨

stapes 镫骨

Middle ear

（ 2 ）运动听小骨的肌 tensor tympani 鼓膜张肌

stapedius 镫骨肌

Internal ear 内耳

bony labyrinth 骨迷路 membranous labyrinth 膜迷路 .

Position: lies in the petrous part of the temporal bone, and consists of two parts:

Internal ear 内耳

The bony labyrinth is composed of the compact bone, and the latter, a series of communicating membranous sacs and ducts, is contained within the bone labyrinth.

The membranous labyrinth is filled with endolymph 内淋巴 ,

The space between the membrnous and bony labyrinth is filled with perilymph 外淋巴 .

bony labyrinth 骨迷路

Cochlea 耳蜗 :

Vestibule 前庭 :

 Bony semicircular canals 骨半规管       

bony labyrinth 骨迷路

(1) Cochlea 耳蜗 :        Cochlear spiral canal 蜗螺旋管 Modiolus 蜗轴       Osseous spiral lamina 骨螺旋板 Scala vestibuli 前庭阶 Scala tympani 鼓阶   

Modiolus

Osseous spiral lamina

Scala vestibuli

Scala tympani

bony labyrinth 骨迷路

   (2)  Vestibule 前庭 :

is the central part of bony labyrinth ， and is medial to the tympanic cavity ， it has 4 walls

On its lateral wall fenestra vestibuli 前庭窗 fenestra cochleae. 蜗窗 The medial wall is the fundus of the internal acoustic meatus 内耳道底  

bony labyrinth 骨迷路

   (2)  Vestibule 前庭 :

On its anterior wall,

a large opening communicates with the scale vestibuli 前庭阶 of cochlea.     

 On the  posterior wall

5 opennings of emicircular canals.  

bony labyrinth 骨迷路

Anterior semicircular canal

Posterior semicircular canal

Lateral semicircular canal

(3) Bony semicircular canals 骨半规管 :

 three in number, the ant., post., and lateral

     simple bony crus 单骨脚ampullar bony crura 壶腹骨脚 bony ampulla 骨壶腹common bony crus 总骨脚

2. Membranous labyrinth 膜迷路

(1) Cochlear duct 蜗管 : in cochlear spiral canal

   (2) Utricle 椭圆囊 and saccule 球囊 :   in vestibule

   (3) Semicircular ducts 膜半规管 :

(1) Cochlear duct 蜗管 :     superior wall : vestibular wall 前庭壁 inferior wall : tympanic wall or basilar membrane 基底膜 spiral organ 螺旋器（ Corti 器）   lateral wall:

前庭壁

外侧壁

鼓壁（基底膜）

螺旋器 （ Corti 器）

labyrinth 膜迷路2. Membranous labyrinth 膜迷路

receptors of balance, respond to linear acceleration and deceleration 直线加速和减速运动

   (2) Utricle and saccule 椭圆囊和球囊 :  

 Connected to each other by utriclosaccular duct 椭圆球囊管 macular utricli 椭圆囊斑 macular sacculi 球囊斑  

Membranous labyrinth 膜迷路

蜗管

、椭圆囊

膜半规管

球囊saccule Utricle

Cochlear duct

Semicircular ducts

    

 (3) Semicircular ducts 膜半规管 :

membranous ampullae 膜壶腹 crista ampullaris 壶腹嵴：

Membranous labyrinth 膜迷路

receptor of balance, which respond to rotation of the head

The Vestibulocochlear Organ

Internal acoustic meatus 内听道

   structures passing through it

Facial nerve

vestibulocochlear nerve

vessels of labyrinth

The position of internal ear

颞骨岩部内耳

Conduction of sound

声波的传导途径

1 、气导 Air conductive pathway ：

brain

•2 、骨导： 是指声波直接振动颞骨，引起蜗管内淋巴的振动，进而刺• 激基底膜上的螺旋器，引起听觉。

可分为气导和骨导两条途径

tympanic membrane chain of auditory ossicles

fenestra vestibuli perilymph within the scala vestibuli

endolymph within cochlear duct spiral organ

nerve impulse vestibulocochlear n.

the external acoustic meatusthe sound wave

Receptors of balance Receptor of hearing

Bony labyrinth: Bony semicircular

canalsVestibule Cochlea

Membranous

Abyrinth ： Cochlear ductSemicircular ducts Utricle 、 saccule

Receptors ： crista ampullaris spiral organ Macular sacculi

Macular utricli

The summary

Fig. 耳

Fig. 鼓膜

Fig. 鼓室

Fig. 迷路

Fig. 迷路

前庭阶

鼓阶

前庭壁

外侧壁

鼓壁（基底膜）

螺旋器（ Corti器）

蜗神经节蜗神经

Facial n.

Veastibular n.

Cochlear n.

1. 外侧壁（鼓膜壁）

鼓膜光锥

鼓室上隐窝

Fenestra cochleae 蜗窗

Promontory 岬

Prominence of facial canal

Pyramidal eminence

Fenestra vestibuli 前庭窗

Conduction of sound 声波的传导

External ear

Tympanic membrane

chain of auditory ossicles

fenestra vestibuli

Internal ear

cochlear n.

spiral organ