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Front 1

EXTERNAL ACOUSTIC MEATUS

CERUMINOUS GLANDS

-describe?
-CC

Back 1

3. Ceruminous glands

a. Modified sweat glands whose secretions combine with secretions of
sebaceous glands to form ear wax or cerumen; cerumen prevents
maceration of the meatal lining by trapped water and may help repel
insects

b. Clinical note: cerumen may decrease hearing acuity by occluding the
external acoustic meatus or by contacting the tympanic membrane
and dampening its vibrations

Front 2

EXTERNAL ACOUSTIC MEATUS

-nerve supply
-blood supply
-fxn

Back 2

4. Nerve supply: auriculotemporal nerve and the auricular branch of the
vagus nerve

5. Blood supply: posterior auricular, superficial temporal, and deep auricular
vessels

6. Function: directs sound waves toward the tympanic membrane

Front 3

MIDDLE EAR

TYMPANIC MEMBRANE
-describe?
-composed of?

Back 3

II. Middle Ear

A. Tympanic membrane

1. Thin, delicate membrane separating the external acoustic meatus from
the tympanic cavity

2. Composed of a middle fibrous layer interposed between a mucosa inter-
nally and skin externally; its external surface faces laterally, inferiorly,
and anteriorly

Front 4

MIDDLE EAR

TYMPANIC MEMBRANE
-"manubrium of the malleus"
-"umbo"?

Back 4

II. Middle Ear
A. Tympanic membrane

3. The manubrium of the malleus attaches to the mucosal side of the tym-
panic membrane, draws it inward, and gives the tympanic membrane the
form of a shallow cone whose apex is called the umbo

Front 5

MIDDLE EAR

TYMPANIC MEMBRANE

-"superior to umbo"

Back 5

II. Middle Ear
A. Tympanic membrane

a. Superior to the umbo, the lateral process of the malleus contacts the
mucosal surface of the tympanic membrane, producing the anterior
and posterior malleolar folds which extend superiorly from the point
of contact

Front 6

MIDDLE EAR

TYMPANIC MEMBRANE
-"B/W MALLEOLAR FOLDS"
-"PARS TENSA"

Back 6

II. Middle Ear
A. Tympanic membrane

b. The part of the tympanic membrane between the malleolar folds is
highly vascular, devoid of a middle fibrous layer, and termed the pars
flaccida; the remaining part of the tympanic membrane is called the
pars tensa

Front 7

MIDDLE EAR

TYMPANIC MEMBRANE

-nerve and blood supply

Back 7

4. Nerve supply: auriculotemporal nerve, tympanic branch of the glossopha-
ryngeal nerve, and the auricular branch of the vagus nerve

5. Blood supply: deep auricular, anterior tympanic, and stylomastoid ves-
sels (the stylomastoid artery is a branch of the posterior auricular artery
and enters the skull through the stylomastoid foramen)