Diseases Of The Nose Throat And Ear

138 THE PHARYNX AND NASOPHARYNX

sheath of fascia extending upwards from the neck to form a capsule. The
parotid duct is formed within the gland by the union of ductules that drain
the lobules, and it runs over the masseter to open on the buccal mucosa
through a small surface papilla opposite the second upper molar tooth. The
facial nerve has an intimate relationship with the parotid gland, entering the
posterior part of its deep surface to divide into its five radiating terminal
branches. The secretory nerve supply of the parotid gland comprises sympa-
thetic fibres from the carotid plexus, and a parasympathetic supply derived
indirectly from the glossopharyngeal nerve. This gives a branch to the otic
ganglion from where fibres pass to the auriculotemporal nerve and thence to
the parotid gland. Sensory nerve fibres reach the parotid gland from the
auriculotemporal and great auricular nerves.

The submandibular gland is about half the size of the parotid gland and lies
between the mandible and the hyoid bone, partly under cover of the mandible.
It is related to the mucous membrane of the floor of the mouth and extends
backwards to the angle of the mandible and forwards as far as the mental
foramen. It is partially enclosed in a sheath of cervical fascia. Its duct emerges
from the medial surface of the gland and proceeds upwards and forwards to
open into the floor of the mouth on the summit of the sublingual papilla. It
derives its sympathetic nerve supply from the plexus around the facial artery,
and its parasympathetic secretory fibres from the lingual nerve via the
submandibular ganglion.

The sublingual gland is the smallest of the paired glands and lies in the
anterior part of the floor of the mouth where it raises up the mucous membrane
as the sublingual fold. The nerve supply is from the lingual nerve which
contains sympathetic and parasympathetic fibres.

The secretions differ in the glands. Parotid secretion is wholly serous
whereas submandibular secretion is partly mucous, and it is this fact that
facilitates stone formation in the submandibular gland.

INFLAMMATORY DISEASES

The parotid gland is the most commonly affected by inflammation.

Acute inflammation in the parotid gland may be non-suppurative or
suppurative. Mumps is an acute non-suppurative inflammation of the parotid
gland, and although it may be unilateral it is more commonly bilateral. It is
due to a virus and affects young children more commonly than adults. An
attack confers a lifelong immunity. The symptoms are of an acute febrile
illness with dryness of the mouth because of suppression of secretion. There
is swelling and tenderness of the gland and some degree of trismus. The
symptoms persist for a few days to be followed by a resolution of the swelling.
There is no specific treatment beyond that of a febrile illness, and, because the
disease is infectious, some degree of isolation is necessary. Mumps occasionally
gives rise to encephalitis and meningitis, and a severe attack may be followed
by a permanent bilateral or unilateral sensormeural deafness in children. In
the adult orchitis or oophoritis may occur, causing sterility in the male.

Acute suppurative parotitis may arise from a septic focus in the mouth, such
as chronic tonsillitis or dental sepsis, and may be found in patients taking
tranquillizer drugs or antihistamines, both of which tend to suppress salivary
excretion. The gland becomes swollen and tender, and there is a pyrexia. The