Description of Anatomy and Physiology

1. Anatomy and Physiology of ENT
Prepared By : Mihir. M.Patel,
Nursing Tutor,GCON,Siddhpur.

2. Anatomy of Ear
The ear is the organ of hearing and is also involved in Balance. It is
supplied by the 8th cranial nerve i.e. Vestibulocochlear nerve.
The ear is divided into
three large parts:
The External ear
The Middle ear
The Inner ear

3. External Ear
The outer ear comprises the pinna and the external auditory meatus. The outer
part of this is cartilaginous. The deep part is bony. The cartilaginous meatus
contains hair follicles and glands which secrete wax. The hair follicles extend
only for a short distance into the ear and are not found in the deeper parts of
the external meatus. The external meatus varies in size and form with growth.

4. Middle Ear
The Middle Ear Includes;
 The Tympanum
 The Eustachian tube
 The Mastoid antrum and cells

5. Inner Ear
The semicircular canals in the inner ear are part of our balance system. The
cochlea is a bony structure shaped like a snail and filled with two fluids
(endolymph and perilymph). The Organ of Corti is the sensory receptor inside
the cochlea which holds the hair cells, the nerve receptors for hearing.

6. Nose and Paranasal Sinuses
External Nose
 The external nose is supported by bone and cartilage.
 The bony part is formed mainly by the nasal bones on each side, and the
frontal process of the maxillary bone.
 The cartilaginous portion is formed by several cartilages which support and
give shape to the lower part of the nose and nasal tip.

7. Nasal Function
1.Olfaction
2.Filtration
3.Humidification and Warming of the Air Passing to the Lungs.
4.Vocal resonance
5.Aesthetic Function

8. Pharynx
Descriptive Purposes Pharynx is divided into three
parts:Nasopharynx, Oropharynx and Laryngopharynx.
Structure:
The wall of the Pharynx contains several types of tissue.
 Mucous Membrane Lining
 Sub mucosa
 Smooth Muscle
Function:
 Passageway for Air and Food
 Warming and Humidifying
 Taste
 Hearing
 Protection
 Speech

9. Larynx/Voice Box
Position: It lies at the level of the 3rd , 4th , 5th and 6th cervical
vertebrae.
Structure: The larynx is composed of several irregularly
shaped cartilages attached to each other by ligaments and
membranes. The Main cartilages are;
 1 Thyroid Cartilage
 1 Cricoid Cartilage
 2 Arytenoid Cartilages
 1 Epiglottis
Function:
 Production of Sound
 Speech
 Protection of the Lower Respiratory Tract
 Passageway for Air
 Humidifying, Filtering and Warming.