- They are usually embedded in the back of the false capsule (rarely in the
- Superior parathyroid is more constant in position (posterior to thyroid &
above inferior thyroid artery).
- lnferior parathyroid may rarely be located in superior mediastinum.
The pituitary gland, or hypophysis, is an endocrine gland about the size of a pea and
weighing 0.5 g. lt is a protrusion of the bottom of the hypothalamus at the base of the
brain, and rests in a small, bony cavity (sella turcica) covered by a dural fold
(diaphragma sellae). The pituitary fossa, in which the pituitary gland sits, is situated in the
sphenoid bone in the middle cranial fossa at the base of the brain.
f,hyt,'A$ii lrekseSrpsix frflqd rlFy'-_
Isoplr{c -.---.-"-.."-_ s(&skrhn{tEy
sheath, medial to the internal
is crossed antero-laterally by
Facial a.'.-'...--.----.-...:*
End$l at the level of the upper
border of thyroid cartilage (between
Co & C+) by dividing into external & internal carotid arteries.
o The incision is carried down through SC tissue & platysma. After division of
external jugular vein, the cervical fascia is opened along the anterior border of
sternomastoid which is retracted laterally to expose the carotid artery.
- From the common carotid artery, passes in the neck inside carotid sheath
- lt then enters carotid canal in the skull, emerges in the upper part of foramen
lacerum, passes in cavernous sinus & ends in the circle of Willis.
- lt is separated from the external carotid by styloid process & structures attached
to it. A Ar*erlor aolemnhetlno
B ra n Ch es : lt is the principal artery of the brain
1) Ophthalmic artery(it gives lacrimal & supraorbital As & ends by
supratrochlear A & dorsal nasal A which anastomoses with facial A).
2) Anterior & middle cerebral arteries.
3) Posterior communicating & anterior choroid arteries.
Surqical ImportanCe: A-V fistula between ICA & the cavernous sinus leading
to throbbing pain and pulsating proptosis.
EgglnSl From common carotid artery & passes outside carotid sheath.
tupraffiFHkr{rt*ry fhfit sa{fimon csru{il ortory
iilrt#$,{*hlsrtBry $uboh{*rirbrl
EndSl At the level of neck of mandible inside parotid gland by dividing into superficial
temporal & maxillary arteries.
1) From its medial aspect:. ascendlng pharyngeal artery.
. Posterior Auricular artery (at the level of the upper border of posterior
. Superficial temporal artery @alled anesthetist's artery, as if ts
used o count pulse by anesthefisfs).
ln malignant goiter, obstruction of the carotid can occur. This causes loss or
weakening of pulsation of the s rperficial temporal artery (Sign of Berry).
BeqinS: from the front of thp external carotid artery, at the level of the fip of greater
- Makes a loop above tip of hyoid bone & is crossed by hypoglossal n.
- Branch ) Supra-hyoid artery.
- Passes above hyoid bone & deep to hyoglossus & hypoglossal n.
- Branches> 2- 3 dorsal lingual arteries.
Passes deep to anterior border of hyoglossus & is crossed by hypoglossal
Branches ) Artery to sublingual gland.
Ends by forming profunda artery of tongue which is separated from
mucosa of lower surface of tongue by its vein.
Lebrrlvlrw Dorsal lhgual arlo{iss $ubm€{rlalarlery
- During tongue bleeding, we should pull tongue outwards as this causes
compression on the lingual a. against the greater horn of hyoid bone.
- lf it is mandatory to tigite the lingual a, ltls better to ligate the 2nd part after cutting
hyoglossus m. because the 1't part is related to hypoglossal nerve.
BeginS: from the front of ECA above the lingual artery.
*. lt ascends deep to the posterior belly of digastric & stylohyoid m. to reach the
tF digastric triangle & runs deep to the submandibular gland.
. lt enters the face at the antero-inferior angle of the masseter and then it
ascends in the face to reach the angle of the eye.
. Should be double ligated during operation for submandibular salivary gland.
1. Angular A. (ECA) with branches of ophthalmic A (lCA).
2. Superficial temporal A. (ECA) with supraorbital & supratrochlear As (lCA).
Aranch of the maxillary artery deep to lateral pterygoid.#
o Passes between the two roots of auriculo-temporal nerve, and then enters the
middle cranial fossa by passing in foramen spinosum with nervus spinosus.
. ln the cranial cavity the artery & its branches lie extra-dural.
EndS: ln the middle cranial fossa. lt divides into anterior & posterior divisions:
. Directed upwards & forwards towards the pterion, grooving the greater
. Then passes upwards & backwards crossing to motor & sensory areas of
the brain, towards a point 1cm behind corona[ suture, grooving the parietal
. It is the artery of extra-dural hemorrhage.
NlTl p\rrion is H-shaped suture between frontal, parietal, temporal & sphenoid bone. tt is
4 cm above mid-zygomatic arch.
. Passes upwards & backwards towards the lambda grooving the temporal
& a vertical line drawn from post. border of mastoid process.
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