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parotid
region
the
parotid region
contains the
largest
salivary
gland
and has
the
'queen
of
the
face'
the
facial nerve.
It contains
vertically disposed
blood vessels and
horizontally
placed
facial nerve
with its horizontal branches.
saLiVaRY
GlaRD
:
·
it has
three
salivary
glands
submandibular
,
sublingual
and
parotid
· there are numerous small
glands
in the
tongue ,
the
palate
,
cheeks and
lips
.
·
saliva
keeps
the
oral
cavity
moist
,
aids
chewing
and
swallowing
as well as it
has
enzymes
that aids breakdown
of
food.
parotid
gland
· it is the
largest salivary grand
· situated below the external
acoustic meatus
,
between the ramus
of
the mandible and
the steenodeidomastoid muscle
. It
overlaps
all
these structures
. It also
overlaps
the
masseter muscle.
·
skin over
the
gland
is
supplied
by
greater
auricular nerve.
~
CaPSULe Of PaROtiD GlaND
:
· the
investing
layer of
deep
cervical fascia forms
capsule
for the
gland
. The fascia
split
-s between the
angle
of
mandible and the mastoid
process
to enclose the
gland
.
·
The
superficial Lamina/paritidomasseric
fascia
,
thick
and
a adherent
to the
gland
,
is attached above
to the
zygomatic
arch.
·
The
deep
lamina is thin
is attached
to
styloid process , tympanic palate , angle of
posterior
border
oframus
of
mandible
&
a part
of
the
deep
lamina
is
thickened
,
between
styloid
process
and
mandible to
form
stylomandibular ligament
, that
separates
the
submandibular
gland
from
paroti
gland
. The
ligament
is
pierced by
external
carotid
artery.
~
External features
:
a. It has
I
surfaces
: )
Superior
superficial
- Anteromedial
Posteromedial
b. It has 3 borders
:
Anterior
- Postelior
Medial/Pharyngeal
edge
<
Relations
:
·
The
apex
overlaps
the
posterior belly of diagastric
and the
adjoining part
of
the carotid Irian
-gle
. The cervical branch of
the facial
neve
and two branches
of
retromandibular
vein
emerge
at
the
apex
.
· the
SUPERIOR Surface
: forms the
upper
end of the
gland
which
is
concave.
It is related to
d. The
cartilaginous part
of
the external acoustic meatus.
b.
The
posterior
border
of
temporomandibular
joint
c
. The
auriculotemporal
nerve
d.
Superficial
temporal
vessels.
·
the superficial
fascia is related
to
:
a. Skin
b.
superficial
Fascia
having
great
auricular nerves anterior branches
, periavicular
lymph
nodes
and
posterior
fibres
of
platysma
or
visovius .
c
. the
parotid
fascia
d. a few
deep parotid
lymph
nodes.
·
veins
:
a
. the
retromandibular
vein is
formed
here
due
to
joining
of
maxillary
vein
superficial
temporal
vein.
b. At the lower
end
,
the retromandibular
vein divides into
the
posterior
and
anterior branches
· nerve
:
the
facial
nerve
is
a branch
of
second brachial
arch. It leaves the skull
through
stylomastoid
foramen.
It enters
parotid gland
through
the
posteromedial
surface
,
crosses the
external carotid
artery
and retromandibular vein. It divides into two branches behind
the neck
of
mandible into the
temporofacial
cervicofacial
branch
The
temporofacial give
rise to
temporal
zygomatic
branch
. The
sricofacial
gives
rise to
buccal
, marginal
mandi
bular and cervical.
structures
at exit
of
stylomastoid
foramen
:
1 .
Posterior auricular neve arises
just
below
stylomastoid
foramen and
supplies
:
a. Auricularis
posterior
b .
Intrinsic muscle
on
back
of
anricle
c
.
Occipitalis
2
.
Communicating
branches with
adjacent spinal
and
cranial
nerves
.
3 .
Stylohyoid
branch
, supplies stylohyoid
muscle
Digastric
branch
,
supplies posterior belly of
diagastric
·
temporal
branch crosses
zygomatic
arch and
supplies
,
a. Orbicularis
oculi
b. Frontalis
c.
Corrugator
supercili
d. avicularis
anterior
e
. Quricularis
superior
f . Intrinsic muscle on
lateral side
of
auricle
.
·
zygomatic
branch
supplies
orbicularis oculi
·
Buccal branch
,
divides
into two
the
superior
is
above
parotid
gland
and inferior
below
parotid gland
·
Marginal
mandibular
supplies
lower
lip
cheek
·
cervical branch
supplies
platysma
Bell's PalaSY
: sudden
paralysis
of
facial
nerve at the
stylomastoid
foramen
,
which
results in
turning of
mouth at corne
, inability
to close
eye
and
disappearance of
nasolabial
fold .
Patey's
faciovenous
plane
: the
parotid
gland
is
formed
by major superficial s
a
few
deep
portion
which is
joined
by
a isthmus' around it
,
which
is divided
by
the facial neve.
Accessory
Process
of
PAROtiD GLAND
:
·
Facial
process
·
Pterygoid
process
·
Glenoid
process
·
Poststyloid
process
BLOOD
SUPPLY
: It is
supplied
by
external
canotid
artery ,
and its branches. The
veins
drain
into
internal
and external
jugulal
veins.
neRVe
SUPPLY
:
a. The
parasympathetic
neeves are secretomotor. Reach
parotid
gland through greater
aurice
las nerve.
Preganglionic
file
Interior
salivatory
nucleus
Glossopharyngeal
nerve
Tympanic
branch
d
Tympanic plexus
↓
lesser
petrosal
neve
Relay
to offic fibers
↓
Postganglionic
fibers
auriculotemporal
Parotid
Thyroid gland
·
the
thyroid
(shield-like)
gland
is
endocrine in nature
,
and is situated
in the lower
part
of front
of
neck and the sides
of
neck.
· it
regulates
calcium metabolism
,
somatic and
psychic growth
as well as
basal metabo
-lic rate. It
is the
only
gland
that uses natural iodine
for
the
production of
its
hormones.
· it has two lobes
, right
and
left
that are
joined
by
the isthmers.
· it
is situated
against
the CS-C7 and
the T1. the lobes extend from fourth
to fifth
tracheal
ring
and
isthmus
from
second to fourth
tracheal
ring.
·
it
grows
in size
during
menstruation
and
pregnancy.
:
·
the true
capsule
is formed from
the
peripheral
condensation
of
the connective tissue
of the
gland
· a dense
capillary plexus
is
present
deep
to the
true
capsule
.
to avoid
hemorrage during operations
.
Thyroid
is removed
along
with the true
capsule
.
·
the false
capsule
is formed
from the
pretracheal layer
of
deep
cervical fascia. It
is thin
along
the
posterior
border
of
the
lobe and dense (thick on the inner
surface of
the
gland
where
it forms a
suspensory ligament
(of
berry)
which
attached the lobe
to
the cricoid
cartilage
.
~
PaRtS Relations
:
the LOBE
is conical
in
shape ,
it has
a. an apex
: it is
pointed upwards
and
slightly
laterally.
It
is
limited
by
the attachment
of
sternothyroid
muscle to
oblique
line
of
thyroid
cartilage
.
it
is related to
superior thyroid
artery
external
laryngeal
nerve.
b .
a base
:
which lies between fourth
and fifth tracheal
ring.
It
is
related
to interior
thyro
-id
artery
laryngeal
nerve.
C. 3
surfaces
:
C.
1
.
Lateral
: convex
and covered
by
S
stenothyroid , sternohyoid , superior belly
of
omon
void
and sternodeidomastoid
can't. border).
c .
2 .
medial
: related
to
2 muscles
: cricoid + interior constrictor
2 tubes
:
resophagus
trachea
2 nerves
: recurrent
external
laryngeal
nerve
C. 3. Posterolateral
surface
: is related
to the carotid sheath and
overlaps
the common
carotid
artery.
d
. 2 borders
:
d
. 1.
anterior
:
it
is thin
and related
to anterior branch
of
superior thyroid
artery.
d. 2 .
Posterior
:
it
is thick
and
related to
:
7 .
Parathyroid gland
anastomosis
of
posterior
branch
of superior thy
-void
artery
descending
branch
of
interior
Interior
thyroid artery
- Parotid duct
only
on
left
side
- the Isthmus connects
and has
:
a. 2 surfaces
:
- 1 .
anterior
: covered
by
: 1 .
left t right
sternobyoid steenothyroid
muscles
anterior
jugular
veins
Fascia
and
skin
2. 2. Posterior
: related to second
to fourth
tracheal
rings
b .
2 borders
:
b. 1.
Upper
border
:
related
to anterior branch
of left
and
right
superior
thyroid
arter
y , they
anastomose
here
b. 2 .
Lower BORDER
:
the interior
thyroid
veins leave here.
· it divides
into 4/
glandular
branches which
pierce
fascia
individually
to reach
lower border .
·
the terminal
part
is
in
intimate relation
with recurrent
laryngeal
nerve.
c. In 3
% individuals
, thyroid
gland
is also
supplied
by
lowest
thyroid
artery ,
a
branch
of brachiocephalic
trunk
. It enters
at lower
part
of
isthmus.
d.
Accessory thyroid
arteries
arising
from tracheal and
oesophagus
arteries also
supply.
venOUS
SUPPLY
:
a.
Superior
thYROID
vein
emerges
at
upper
pole
of
lobe
along
with
superior thyroid artery
and
drains into internal
jugular
vein
↓
In
ning
i
a
b. Middle thyroid vein
emerges
at middle
of
lobe ,
THYROIC HAND
I
< Middle thyroid
Vein
is
short
and wide
channel. Drains
into interna
vein of
KOCHER - e
jugular
vein
Inferiore -
vein
Er
c.
interior
thyroid
vein
emerge
at lower border
Xceft
Brachiocephali
a
where
they
form a
plexus
in front
of
trachea
Lower
L
cervice
W drains
into
brachiocephalic
vein.
· umme
nose
a.
vein
of Rocher
might
emerge
between middle
and interior branch
and drains
into internal
jugular
vein
.
Lymphatic Drainage
:
· the
lymph
nodes from
upper part of
gland
reach
upper
cervical
lymph
nodes
directly
or
through
prelaryngeal
nodes
·
the
lymph
nodes
from lower
part
of
gland
reach lowel cervical
lympl
nodes
directly
or
through
pretracheal
paratracheal
nodes
nerve
SUPPLY
:
·
mainly by
middle cervical
ganglia
and
partly by
interior
and
superior
cervical
ganglia
they
are vasoconstrictor
.
applied
anatomy:
any
swelling of thyroid gland (goitre)
is
to
be assessed from
behind
Removal
of thyroid gland along
with true
capsule might
be
necessary
in
hyperthy
roidism
.
Hypothyroidism
causes cretinism
in
children
Myoxedema
in adults.
Pressure
symptoms
and
neve involvements
are seen
in carcinoma
of
gland
lead
-ing
to
dysponea , dysphagia , dysphonia
.
Benign
tumours
may
displace
or
compress
neighbouring
structures.
