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→Structure
Proximally, the auricular cartilage is rolled into a funnel shape, known as the '''concha'''. The '''scutiform''' cartilage lies rostromedially in the lower ear canal and provides support. The '''annular''' cartilage lies between the proximal horizontal ear canal and the bony '''acoustic process''' of the [[Skull and Facial Muscles - Anatomy & Physiology#Temporal Bone (os temporale)|typmanic bulla]], connected by ligaments. The vertical ear canal lies in a rostroventral orientation before bending medially to become the horizontal canal.
Proximally, the auricular cartilage is rolled into a funnel shape, known as the '''concha'''. The '''scutiform''' cartilage lies rostromedially in the lower ear canal and provides support. The '''annular''' cartilage lies between the proximal horizontal ear canal and the bony '''acoustic process''' of the [[Skull and Facial Muscles - Anatomy & Physiology#Temporal Bone (os temporale)|typmanic bulla]], connected by ligaments. The vertical ear canal lies in a rostroventral orientation before bending medially to become the horizontal canal.
===Microclimate of the Ear Canal===
===Microclimate of the Ear Canal===
In the tissues medial to the ear canal lie the auricular and superficial temporal arteries. Laterally is the '''parotid salivary gland''' and also a branch of the [[Cranial Nerves - Anatomy & Physiology|facial nerve]], external maxillary vein and branches of the external carotid artery. The facial nerve exits the skull through the stylomastoid foramen behind the osseous bulla; it passes below the rostroventral aspect of the horizontal ear canal. The '''auriculo-temporal''' branch of the mandibular portion of the [[Cranial Nerves - Anatomy & Physiology|trigeminal nerve]] (CN V) and branches of the facial nerve pass rostral to the vertical ear canal.
In the tissues medial to the ear canal lie the auricular and superficial temporal arteries. Laterally is the '''parotid salivary gland''' and also a branch of the [[Cranial Nerves - Anatomy & Physiology|facial nerve]], external maxillary vein and branches of the external carotid artery. The facial nerve exits the skull through the stylomastoid foramen behind the osseous bulla; it passes below the rostroventral aspect of the horizontal ear canal. The '''auriculo-temporal''' branch of the mandibular portion of the [[Cranial Nerves - Anatomy & Physiology|trigeminal nerve]] (CN V) and branches of the facial nerve pass rostral to the vertical ear canal.
==The Tympanic Membrane==
This epithelial structure separates the external from the middle ear. Below the stratified keratinising outer epithelium is a connective tissue lamina propria, with a cuboidal mucosal epithelium on the inner surface. The tympanic membrane is divided into the '''pars flaccid''' dorsorostrally, which lies next to the '''manubrium of the malleus''', and the '''pars tensa''' ventrally. The C-shaped manubrium inserts into the '''lamina propria''', extending towards the middle of the pars tensa. Foreign bodies and other damage (severe otitis externa, ascending pathology from middle ear) can result in rupture of the tympanic membrane in the pars tensa region. Defects of the tympanic membrane heal by epithelial migration bridging over the defect, then development of a granulation bed below.
- ''Cochlea'': forms a spiral around a central hollow core of bone, called the modiolus,which contains the cochlear nerve. The spiral lamina projects into the spiral canal, partially bisecting the lumen into two parts, which are called the scala tympani and the scala vestibuli. The scala media (the cochlear duct) is inbetween these two parts.
- ''Cochlea'': forms a spiral around a central hollow core of bone, called the modiolus,which contains the cochlear nerve. The spiral lamina projects into the spiral canal, partially bisecting the lumen into two parts, which are called the scala tympani and the scala vestibuli. The scala media (the cochlear duct) is inbetween these two parts.
==Function - Hearing==
==Function - Hearing==