A basic information to gain knowledge about ENT

1. Amrutha Nayaka P,
3rd year Bsc(N),
Kidwai College Of
Nursing,
Bengaluru.

2. ANATOMY OF EAR
The ear is the organ of hearing and balance.
The parts of the ear include:
1. External Ear
2. Middle Ear
3. Internal Ear
1. EXTERNAL EAR
*Pinna
*External auditory
meatus
*Tympanic membrane
2. MIDDLE EAR
*Auditory ossicles
3. INTERNAL EAR
*cochlea
*Vestibule
*Semicircular canals

3. External or outer ear, *Pinna This is the outside part of the ear.
*External auditory canal or tube. This is the tube that connects the
outer ear to the inside or middle ear.
*Tympanic membrane (eardrum). The tympanic membrane divides the
external ear from the middle ear.
Middle ear (tympanic cavity),
Ossicles. Three small bones that are connected and transmit the
sound waves to the inner ear. The bones are called:
*Malleus
*Incus
*Stapes
Eustachian tube: A canal that links the middle ear with the back of the
nose. The eustachian tube helps to equalize the pressure in the
middle ear. Equalized
pressure is needed for the proper transfer of sound waves. The
eustachian tube is lined with mucous, just like the inside of the nose
and throat.

4. Inner ear,
Cochlea: This contains the nerves for hearing.
Vestibule: This contains receptors for balance.
Semicircular canals: This contains receptors for balance
PHYSIOLOGY OF EAR
1.Tympanic membrane : It consists of connective tissue and is kept in the
position by the handle of the malleus. It forms the lateral wall of middle ear.
Functions:
*It acts as a pressure receiver i.e it is extremely sensitive to pressure changes
prodced by sound waves on its external surface.
*It acts as a resonator i.e it starts vibrating (in and out movements) freely when
the sound waves strike.
*It critically dampens(stops the vibrations of) the sound waves i.e. strectching
the tympanic membrane, its vibrations are stopped almost immediately.

5. 2.Ear ossicles or auditory ossicles: There are three minute bones(ear) ossicles,
*Malleus(hammer)
*incus(anvil)
*stapes(stirrup).
3.Pharyngo tympanic tube/Eustachian tube:
It is 4-5 cm in length and connects the middle ear cavity with the pharynx. It
serves to equalize the pressure on the two
sides of the tympanic membrane when atmospheric pressure(high altitude) or
increases(deep sea diving).
4.Two skeletal muscles:
'Tensor tympani' and 'stapedius'
a) Tensor tympani: It is sttached to the neck of malleus
b) Stapedius: It is attached to neck of the stapes.
Function:
Both the muscles, the tensor tympani and stapedius can be reflexly activated
by loud sounds and this reflexly decreases the amplitude of sound vibration of
the
tympanic membrane. thus they serve a protective function by protection of the
internal ear by loud sounds.(tympanic reflex or acoustic reflex).

6. DISORDERS OF EAR
1. Acute Otitis media : Inflammation in the middle ear
lasting less than 6 weeks.
2. Cholesteatoma : Tumor of the middle ear or mastoid,
or
both, that can destroy structures of the temporal
bone.
3. Chronic Otitis media : Repeated episodes of acute
otitis media causing irreversible tissue damage
and persistent tympanic membrane perforation.
4. Conductive Hearing loss : loss of hearing in which
efficient sound transmission to the inner ear is
interrupted by some obstruction or disease process.
5. Tympanoplasty : Surgical repair of the tympanic
membrane.

8. ANATOMY OF NOSE
Nose is a pyramidal shaped structure lying between the two eyes on the face.
It is partly bony and partly cartilaginous. It has an apex the root of nose present
between the two eyes and a base which has two anterior nasal apertures.
Each nasal aperture leads to nasal cavity. The two nasal cavities are separated
from each other by medial wall know as nasal septum. Each nasal cavity is boun
laterally by lateral wall which has bony shelf like projections, the nasal conchae
the part of nasal cavity inferior to the nasal turbinates is the meatus of nose.
Each nasal cavity has three turbinates superior, middle and inferior tubinates
and three meatuses superior, middle and inferior meatuses. Part of the nasal
cavity opposite mucosa (responsible for smell) lines this part of nasal cavity and
is of yellow colour.

9. PHYSIOLOGY OF NOSE
1.Breathing
2.Air conditioning of inspired air
3.Protection of lower airway
4.Ventilation and drainage of p.n.s.
5.Olfaction
6.Nasal resistance
7.Vocal resonance
8.Nasal refluxes

10. DISORDERS OF NOSE
1.Common cold
2. Sinusitis
3. Epistaxis : bleeding from nose
4. Foreign body in nose
5. Infection of sinuses and other upper respiratory
tract infections
6. Polyps in the nasal sinuses
7. Rhinitis : Inflammations of the mucous
membrane of the nose.
8. Deviated nasal septum : when nasal septum is
not in the midline

11. ANATOMY OF TONGUE
Tongue is a muscular organ lying in the oral cavity proper.
It is a mass of muscle lined superiorly and inferiorly by mucous
membrane. It is divided into anterior 2/3rd and posterior 1/3rd by V shaped
depression known as sulcus terminalis. The superior surface of anterior
2/3rd of tongue is rough while inferior surface is smooth.
Whereas the posterior end of the ueg is attached to hyoid bone, the
anterior end of the tounge is free. Superior surface of the tongue is
rough because of projection of mucosa known as the papillae.
There are three types of papillae i.e.
1.Filiform
2. Fungiform
3. Circuvallate papillae.

12. a) Filiform papillae: They are conical, present all over anterior 2/3rd of
tongue. They are most numerous and do not possess taste
buds(structures for tasting things)
b) Fungiform papillae: They are mushroom shaped papillae present over
anterior 2/3rd of tongue. They possess taste buds.
c) Circumvallate papillae: They are visible by naked eyes. They are
present just anterior to sulcus terminalis. They are circularand are
surrounded by a circular depression the moth. Their walls possess taste
buds.
PHYSIOLOGY OF TONGUE
1.Taste
2.Helps in speech
3.Helps in swallowing food.
4.Helps in sensation of thirst.

13. DISORDER OF THE THROAT
1. Tonsillitis
2. Laryngitis ( inflammation of the larynx)
3. Laryngeal Cancer
4. Tracheostomy