What is the blood supply to the external ear?
The posterior auricular artery is also the main blood supply to the external ear.
Does the eardrum have a blood supply?
Blood Supply and Lymphatics The lateral surface of the tympanic membrane is supplied by the deep auricular branch of the maxillary artery. The medial surface is irrigated by the anterior tympanic artery, a branch of the maxillary artery, and the posterior tympanic artery, a branch of the posterior auricular artery.
What Innervates external auditory canal?
The lateral surface of the tympanic membrane, the external auditory canal, and the external acoustic meatus are all innervated by nervus intermedius (a branch of CN VII), the auriculotemporal nerve (CN V3), and the auricular branch of the vagus nerve.
What does the external auditory canal contain?
The external auditory canal is a cylindrical canal, comprised of cartilage and bone, and lined by a thin layer of skin that is rich in ceruminous and sebaceous glands.
What is the function of the external auditory canal?
Once the sound waves have passed the pinna, they move two to three centimetres into the auditory canal before hitting the eardrum, also known as the tympanic membrane. The external auditory canal’s function is to transmit sound from the pinna to the eardrum.
What is the function of the auditory tube?
The main function of the eustachian tube is ventilation of the middle ear and maintenance of equalized air pressure on both sides of the tympanic membrane (eardrum). Closed at most times, the tube opens during swallowing. This permits equalization of the pressure without conscious effort.
Are there blood vessels in the ear canal?
The labyrinthine artery enters the internal auditory canal but divides into two branches shortly after entering into the canal, the common cochlear artery and the anterior vestibular artery.
What is the auditory canal?
external auditory canal, also called external auditory meatus, or external acoustic meatus, passageway that leads from the outside of the head to the tympanic membrane, or eardrum membrane, of each ear. The canal is nearly 1 inch (2.5 cm) in length and is lined with skin that extends to cover the tympanic membrane.
What is the function of tympanum?
The tympanic membrane (also tympanum or myrinx), is a thin membrane that separates the external ear from the middle ear. Its function is to transmit sound from the air to the ossicles inside the middle ear. The malleus bone bridges the gap between the eardrum and the other ossicles.
What is Vestibulocochlear?
The vestibulocochlear nerve (auditory vestibular nerve), known as the eighth cranial nerve, transmits sound and equilibrium (balance) information from the inner ear to the brain.
What lines the auditory canal and what is its function?
The canal is nearly 1 inch (2.5 cm) in length and is lined with skin that extends to cover the tympanic membrane. Tiny hairs directed outward and modified sweat glands that produce cerumen (earwax) help to discourage insects from entering the ear.
Where the auditory tube opens?
The tube opens about 1.25 cm behind and slightly below the posterior end of the inferior turbinate. The bony portion is widest at its tympanic end. It passes through the squamous and petrous portions of the temporal bone but narrows gradually to the isthmus, which is the narrowest part of the eustachian tube.
