The Organ of Hearing

(Organon Auditus; The Ear)

Dr. Anvari

The external ear

� auricula or pinna

� external acoustic � external acoustic meatus.

Nerves� Auriculares anterior

& superior & the intrinsic muscles on the lateral surface are supplied by the temporal branch of the facial nerve

� the Auricularis posterior and the intrinsic muscles on the cranial surface by the posterior auricular branch of the same nerve.

Arteriesof the auricula

� posterior auricularfrom the external carotid

� anterior auricular� anterior auricularfrom the superficial temporal.

Ear (Microtia)

External Acoustic Meatus(external auditory canal or meatus)

� S-shaped curve = 2.4 cm

� cartilaginous portion = 8 mm

� osseous portion = 16 mm

• tympanic sulcus

� pars externa

� inward, forward, and slightly upward

� pars media

� inward and backward

� pars interna

� inward, forward, and slightly downward

Ear Wax is Your Friend!

• Waxy sebaceous secretions + skin cells• Anti-pseudomonal due to acidic PH• Moisture repelling waxy consistency• Occasionally needs removal if:• Occasionally needs removal if:

– Impairs hearing– Interferes with hearing aids– Impairs inspection– Cerumen “dam” causes water trapping

Low Tech Wax Removal

Arteries and nerves

� posterior auricular

� Deep auricular (maxillary)

� superficial temporal.

� auriculotemporal (V3)

�

� auricularbranch of the � superficial temporal. � auricularbranch of the vagus.

Anatomy of the Ear

Parts of the ear

� External (auricle and external external auditory canal)

� Channel sound in

� Makes ear wax

� Self cleaning

Proper Technique?

Ant in external auditory meatus

Exostosis

Otitis Externa (O.E.)

� more common in swimmers/divers

� most commonly bacterial

� 90% pain (otalgia), 10% itch� 90% pain (otalgia), 10% itch

� pain with manipulation

� lymph node enlargement

� foul greenish-tinged discharge

� eczema, psoriasis, allergy & trauma

Clinical Appearance of O.E.

Suppurative O. E.

Suppurative O. E.

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