external carotid artery

EXTERNAL CAROTID ARTERY

INTRODUCTION External carotid artery is the chief artery which

supplies to structures in the front of the neck and in the face.

Description of branches of it with their applied anatomy .

ECA -ligation

EMBRYOLOGY OF ECA During the fourth and

fifth weeks of embryological development, when the pharyngeal arches form, the aortic sac gives rise to arteries – the aortic arches.

The aortic sac is the endothelial lined dilation, it is the primordial vascular channel from which the aortic arches arise.

In the initial stage there are pairs of aortic arches, which are numbered I, II, III, IV, and V. This system becomes

altered in further development.

3rd Arch : forms common carotid artery, first (cervical) part of internal carotid artery (rest of internal carotid arises from dorsal aorta), and external carotid artery.

COMMON CAROTID ARTERIES

Right common carotid artery is a branch of the brachiocephalic artery.It begins in the neck behind the right sternoclavicular joint.

Left common carotid artery is a branch of the arch of aorta.It ascends to the back of the left sternoclavicular joint and enters the neck.

In the neck,each artery runs upwards within the carotid sheath,under cover of the anterior border of the sternocleidomastoid muscle.

CAROTID SHEATH Carotid sheath is

condensation of the fibroareolar tissue around the main vessels of the neck.

CONTENTS:It contains the common and internal carotid arteries,internal jugular vein and the vagus nerve.

In the sheath,common carotid artery is medially placed.Vagus nerve lies in between.

RELATIONS The ansa

cervicalis lies embedded in the anterior wall of the carotid sheath.

The cervical sympathetic chain lies behind the sheath.

BIFURCATION OF COMMON CAROTID ARTERY Common carotid artery

bifurcates into external and internal carotid arteries at the level of upper border of the thyroid cartilage.

Two structures of importance at the bifurcation are

Carotid sinus

Carotid body

CAROTID SINUS Carotid sinus is slight dilatation at the termination

of the common carotid artery or the beginning of the internal carotid artery.

It receives a rich innervation from the glossopharyngeal and sympathetic nerves.

FUNCTION:

Carotid sinus acts as a baroreceptor or pressure receptor and regulates pressure.

APPLIED ANATOMYCAROTID SINUS SYNDROME Loss of consciousness due to simple head movements. Hypersensitivity of the carotid sinus due to an

unknown etiology. Sudden slight pressure changes, such as that occasioned

by movement of the head, may result in stimulation of the carotid sinus.

Impulses transmitted by the sinus reduce blood pressure and slow the pumping action of the heart.

Thus decreasing blood supply to the brain and resulting in sudden loss of consciousness.

While supporting the mandible care should be taken not to apply pressure on the carotid sinus.

CAROTID BODY Carotid body is a small,oval reddish-brown

structure situated behind the bifurcation. It receives nerve supply mainly from the

glossopharyngeal nerve, but also from the vagus and sympathetic nerves.

FUNCTION:

Carotid body acts as a chemoreceptor and responds to changes in the oxygen and carbon dioxide and Ph content of the blood.

EXTERNAL CAROTID ARTERY Generally,it lies anterior to the internal carotid

artery.

It is the chief artery of supply to structures in the front of the neck and in the face.

SURFACE MARKING ECA is marked by joining

the following two points.

-A) point on the anterior border of the sternocleidomastoid muscle at the level of the upper border of the thyroid cartilage.

-B) second point on the posterior border of the neck of the mandible.

The artery is slightly convex forwards in its lower half and slightly concave forwards in its upper half.

B

A

COURSE ECA begins in the carotid

triangle at the level of upper border of thyriod cartilage opposite the disc between the third and fourth cervical vertibrae.

In the carotid triangle,it lies under cover of the anterior border of the sternocleidomastiod muscle

As the artery ascends ,it passes deep to the post. Belly of digastric and stylohyoid muscle and terminates behind the neck of the mandible by dividing into the maxillary and superficial temporal arteries.

Has slightly curved course,so that it is anteromedial to ICA in it lower part,and anterolateral to the ICA in its upper part.

RELATIONSIN THE CAROTID TRIANGLE

Superficially—Cervical branch of facial nerve

Hypoglossal nerve

Facial,lingual,and superior

thyriod veins

Deep to the artery— Wall of pharynx

Superior laryngeal nerve

Ascending pharyngeal artery

ABOVE THE CAROTID TRIANGLE

Lies deep in the substance of the parotid triangle.

Within the gland, it is related

Superficially—Retromandibular vein

Facial nerve

Deep to the artery—ICA

Structures passing between ECA and ICA

Styloglossus

Stylopharyngeus

IXth nerve

Pharyngeal branch of

Xth nerve

Styloid process

BRANCHES

Total of 8 branches ANTERIOR— Superior thyroid

Lingual

Facial POSTERIOR-- Occipital

Posterior auricular MEDIAL— Ascending

pharyngeal TERMINAL— Maxillary

Superficial temporal

Mn:Sister Lucy's Powdered Face Often Attracts Silly Medicos"

ANTERIOR BRANCHES

SUPERIOR THYRIOD ARTERYORIGIN:Arises from the front of

ECA below the tip of greater cornua of hyoid bone.

COURSE: Runs downwards and forwards parallel and just superficial to the extenal laryngeal nerve.

- It passes deep to omohyoid ,sternohyoid, sternothyroid and reaches the upper pole of lateral lobe of thyroid and divides into its terminal branches.

It is accompanied by same-named vein.

BRANCHES:

INFRAHYOID ARTERY :A small vessel, passing inferior to the hyoid bone to anastomose with its counterpart on the other side.

-Supplies infrahyiod muscles.

STERNOCLEIDOMASTOID ARTERY :Passes ventral to the carotid sheath, suppling SCM on its deep surface.

SUPERIOR LARYNGEAL ARTERY :Passes superficial to the inferior pharyngeal constrictor muscle and pierces the thyrohyoid membrane, accompanied by the internal laryngeal nerve.

-Within the larynx, it serves its muscles, glands, and mucosa.

CRICOTHYROID ARTERY: Supplies cricothyriod muscle and anastomoses with the artery of the opposite side.

GLANDULAR BRANCHES Supplies the upper one third of the lobe and the upper half of the isthmus.

Anterior branch

Posterior branch

Lateral branches(occasionally).

The anterior branch descends on the anterior border of the lobe and continues along the upper border of the isthmus to anastomose with its fellow of the opposite side.

The posterior branch descends on the posterior border of the lobe and anastomoses with the ascending branch of the inferior thyriod artery.

Occasionally, a lateral branch is present, which supplies the lateral aspect of the lateral lobe.

APPLIED ANATOMY The arch of superior thyroid artery is characteristic –

diagnostic landmark The artery and external laryngeal nerve are close to each

other higher up, but diverge slightly near the gland.

- So, ligature of superior thyroid artery in thyroid surgery should be made close to the gland in order to avoid injury of the external laryngeal nerve.

-Damage to the external laryngeal nerve causes some weakness of phonation due to loss of tightening effect of the cricothyriod on the vocal cord.

Intra-arterial infusion chemotherapy for laryngeal and hypopharyngeal cancers.

LINGUAL ARTERYORIGIN:Arises from ECA opposite the

tip of the greater cornua of hyoid bone.

-It may arise in common with the facial artery, then becoming the linguofacial trunk.

COURSE:Divided into three parts by hypoglossus muscle.

FIRST PART – In carotid triangle, extends from origin to the posterior border of hyoglossus.

- Rests on the middle constrictor,forms a upward loop which is crossed by hypoglossal nerve. This loop permits the free movements of the hyiod bone.

SECOND PART – Deep to hyoglossus, runs horizontally forward along the upper border of hyoid bone between hyoglossus laterally and middle constrictor, stylohyoid ligament medially.

THIRD PART [ ‘arteria profunda linguae’ ]—Also called as deep lingual artery.

-It runs upwards along the anterior Border of hyoglossus, then horizontally forwards on the undersurface of tongue on each side of frenum linguae.

-In vertical course,it lies b/t the genioglossus medially & inferior longitudinal muscle of tongue laterally. Horizontal part is accompanied by lingual nerve.

BRANCHESHas four branches:

SUPRAHYOID ARTERY :Courses along the superior border of the hyoid bone, serving the muscles in its vicinity, and anastomosing with its counterpart on the other side.

DORSAL LINGUAL ARTERY: Arises deep to the hyoglossus muscle. It ascends to the posterior dorsum of the tongue to supply the palatoglossal arch, mucous membrane of the tongue, palatine tonsil, and some of the soft palate, freely anastomosing with other arteries in its vicinity.

SUBLINGUAL ARTERY :Arises at the border of the hyoglossus muscle to course between the genioglossus and mylohyoid muscles on its way to the sublingual gland, which it supplies along with adjacent muscles in addition to the mucous membrane of the floor of the mouth and gingiva.

-Branches of this artery anastomose with the submental branch of the facial artery.

DEEP LINGUAL ARTERY:Terminus of the lingual artery.

-Passes along the ventral aspect of the tongue, immediately deep to the mucous membrane, accompanied by the lingual nerve, to its apex, where it will anastomose with its counterpart of the other side.

APPLIED ANATOMY

In surgical removal of tongue , first part of artery is ligated before it gives any branches to the tongue or tonsil.

 LIGATION OF LINGUAL ARTERY :

Incision – circling the lower pole of submandibular gland.

- Skin, platysma, deep fascia incised, submandibular gland exposed , lifted, tendon of diagastric visible.

-Free border of mylohyoid muscle seen, hypoglossal nerve identified. Digastric tendon pulled downwards –enlarges the digastric triangle, hyoglossus muscle visible.

- Muscle divided bluntly, in the gap of its vertical fibers lingual artery found & ligated.

SUBLINGUAL ARTERY

Injury occurs in premolar & molar region, when sharp instrument or rotating disks slips off a lower molar & injure the floor of mouth.

-May present problems to the surgeon attempting to ligate its source because it may arise from the submental branch of the facial artery rather than from the lingual artery.

FACIAL ARTERYORIGIN: Arises from the ECA just above the tip of

greater cornua of hyoid bone.

COURSE: Runs upwards in -- neck as cervical part ; face -- facial part.

Tortuous course—In neck allows free movements of pharynx during deglutition,

on face -- free movements of mandible , lips, & cheek during mastication & facial expressions, escapes traction & pressure during movements.  

.    

Cervical part : Cervical part Runs upwards on superior constrictor of pharynx deep to the posterior belly of digastric.

-It grooves the posterior border of submandibular gland, makes S-bend [2 loops] 1st winding down over submandibular gland & then up over the base of mandible.

Facial part:The vessel enters the face by winding around the base of the mandible, and by piercing the deep cervical fascia,at the anteroinferior angle of the masseter muscle.

It runs upwards and forwards deep to the risorus,

to a point 1.25cm lateral to the angle of the mouth.

Then it ascends by the side of the nose upto the medial angle of the eye where it terminates by anastomosing with the dorsal nasal branch of the ophthalmic artery.

SURFACE MARKING OF FACIAL PART

By joining the following 3 points.

1)A point o the base of the mandible at the anteriorinferior border of the masseter muscle.

2)A second point 1.2cm lateral to the angle of the mouth.

3)A point at the medial angle of the eye.

More tortuous b/n first two points.

12

3

VARIATIONS : May arise in common with lingual artery constituting “linguo-facial trunk”.

-Occasionly ends by forming submental artery and freqently extends only as high as the angle of mouth or nose.

-Deficiency is compensated by enlargement of one of neighbouring arteries.

BRANCHESCERVICAL PART:

ASCENDING PALATINE ARTERY: Originates near the origin of facial artery.

-It passes upwards between the stylopharyngeus and styloglossus muscles, to supply the levator veli palatini, superior pharyngeal constrictor and neighboring muscles, soft palate, tonsils, and auditory tube.

TONSILLAR A RTERY: Passes between the styloglossus and medial pterygoid muscles and pierces the superior pharyngeal constrictor muscle to supply the palatine tonsil and the posterior tongue.

GLANDULAR ARTERIES: Distribute as three or four vessels to the submandibular gland to supply it and the adjacent area.

SUBMENTAL ARTERY: Arises from the facial artery near the anterior border of the masseter muscle.

-It follows the base of the mandible in an anterior direction and turns onto the chin at the anterior border of the depressor anguli oris muscle and accompanies with the mylohyiod nerve.

-It supplies the submental triangle and sublingual salivary gland and forms anastomoses with several arteries in its vicinity, including the mental and sublingual arteries.

FACIAL PART:

INFERIOR LABIAL ARTERY: Originates near the corner of the mouth, passes deep to the depressor anguli oris muscle, and pierces the orbicularis oris muscle.

-The artery courses superficial to that muscle, supplying it as well as the substance of the lower lip.

-It forms an anastomosis with its counterpart of the other side and with branches of the mental and submental arteries.

SUPERIOR LABIAL ARTERY: Arises just above the inferior labial artery. It passes

superficial to the orbicularis oris muscle in the upper lip to serve that muscle as well as the substance of the upper lip.

- It sends a small twig, the SEPTAL BRANCH to supply anteroinferior part of the nasal septum and another one, the ALAR BRANCH, into the wing of the nose.

-The terminus of the vessel will anastomose with its counterpart of the opposite side.

LATERAL NASAL ARTERY: Small branch arising at and passing into the wing and bridge of the nose.

-This supplies ala and dorsum of the nose. This vessel will anastomose with various other arteries in its vicinity.

ANGULAR ARTERY: Is the terminal continuation of the facial artery, supplying the tissues in the vicinity of the medial corner of the eye and anastomosing with dorsal nasal branch of the ophthalmic artery.

APPLIED ANATOMY Facial Artery

Compression:

Applying pressure to the facial artery as it passes over the inferior border of the mandible just anterior to the angle will diminish blood flow to that side.

o Can be injured –during operative procedures on lower premolars & molars, if instrument enters the cheek at inferior vestibular fornix., also while attempt to open a buccal abscess or mucocoele.

In mand. 1st molar region care must be takent not to injure the facial artery while extending the vertical incision down the vestibule during surgical extraction of mandibular impaction

So it is recommended that start vertical incision from the vestibule in upward direction.

While excising the sbmandibular gland,the facial artery should be ligated at two points and should be scured before dividing it, otherwise it may retract through stylomandibular ligament causing serious bleeding.

LIGATION OF FACIAL ARTERY.

Exposed --at the point crossing the lower border of

mandible .

Using contracted masseter as a landmark, pulse of facial

artery felt at point situated anterior to the attachment of masseter.

,

Incision - at least half inch below the border of mandible & parallel to it.

Skin,platysma and deep cervical fascia cut

Artery is accompanied by facial vein & crossed superficially by marginal mandibular branch of facial nerve

Pulse of facial artery felt. Artery- isolated, tied & cut

Wound closed in layers.

Anaesthetist’s arteries:

Rather than using the radial artery for determining pulse rate, anesthesiologists use either the superficial temporal artery, accessed anterior to the ear just superior to the zygomatic arch, or the facial artery just as it crosses the mandible anterior to the masseter muscle.

POSTERIOR BRANCHES

OCCIPITAL ARTERYORIGIN:Arises in carotid

triangle from posterior aspect of ECA ,opposite the origin of facial artery.

-It is crossed at its origin by hypoglossal nerve.

COURSE: Passes backwards and upwards along & under cover of lower border of post. Belly of diagastric , crossing carotid sheath, hypoglossal & accessory nerves.

Then it runs deep to the mastiod process and muscles attached to it i.e.,sternocleidomastiod,

digastric etc.

Then crosses the rectus capitus lateralis,superior oblique,and semispinalis capitus muscle at the apex of the posterior triangle.

Finally it pierces the trapezius muscle and ascends in a tortuous course in the superficial fascia of the scalp.

Its terminal portion comes to lie along the greater occipital nerve.

BRANCHESIN THE CAROTID TRIANGLE STERNOMASTOID BRANCHES – Two in

no.,upper branch accompanies the accessory nerve and lower branch arises near the origin of the occipital artery. Supplies sternomastoid m.

IN THE POSTERIOR TRIANGLE and SCALP REGION:

AURICULAR BRANCH: Passes superficial to the mastoid process to reach and supply the back of the auricle.

MASTOID BRANCH:–Enters cranial cavity through mastoid foramen, supplies mastoid air cells in the dura and diploe.

MENINGEAL BRANCH – Ascends with the

internal jugular vein and enters the skull through jugular foramen & condylar canal, supplies dura of posterior cranial fossa.

MUSCULAR BRANCH-Supply the Digastricus, Stylohyoideus, Splenius, and Longissimus capitis.

DESCENDING BRANCH : The largest branch of the occipital, descends on the

back of the neck, and divides into a superficial and deep portion.

-The superficial portion runs beneath the Splenius, giving off branches which pierce that muscle to supply the Trapezius and anastomose with the ascending branch of the transverse cervical artery.

-The deep portion runs down between the Semispinales capitis and colli, and anastomoses with the vertebral and with the a. profunda cervicalis, a branch of the costocervical trunk.

The terminal branches of the occipital artery(occipital branches) are distributed to the back of the head: they are very tortuous, and lie between the integument and Occipitalis, anastomosing with the artery of the opposite side and with the posterior auricular and temporal arteries, and supplying the Occipitalis, the integument, and pericranium

APPLIED ANATOMY

Superficial branch anastomosis with ascending branch of transverse cervical artery. Deep branch of descending br of occipital artery anastomosis with deep cervical artery.

Important for neurosuegeons.

POSTERIOR AURICULAR ARTERYORIGIN: Arises from the

posterior aspect of the external carotid artery just above the posterior belly of the digastric.

COURSE:It runs upwards and backwards deep to parotid gland, but superficial to the styloid process.It crosses the base of the mastiod process and ascends behind the auricle.

BRANCHES Besides several small branches to the Digastricus,

Stylohyoideus, and Sternocleidomastoideus, and to the parotid gland, this vessel gives off three branches:

Stylomastoid.

Auricular

Occipital.

Stylomastoid Artery (a. stylomastoidea) :Enters the stylomastoid foramen along with facial nerve and supplies the tympanic cavity, the tympanic antrum and mastoid cells, and the semicircular canals. In the young subject a branch from this vessel forms, with the anterior tympanic artery from the internal maxillary, a vascular circle, which surrounds the tympanic membrane.

Auricular Branch (ramus auricularis): Ascends behind the ear, beneath the Auricularis posterior, and is distributed to the back of the auricle, upon which it ramifies minutely, some branches curving around the margin of the cartilage, others perforating it, to supply the anterior surface.

-It anastomoses with the parietal and anterior auricular branches of the superficial temporal.

Occipital Branch (ramus occipitalis): Passes backward, over the Sternocleidomastoideus, to the scalp above and behind the ear. It supplies the Occipitalis and the scalp in this situation and anastomoses with the occipital artery.

MEDIAL BRANCH

ASCENDING PHARYNGEAL ARTERY

ORIGIN:The smallest branch arising from the medial side of the external carotid artery, near its commencement.

COURSE: Ascends vertically between the internal carotid and the side of the pharynx, to the under surface of the base of the skull, lying on the Longus capitis.

BRANCHES

PHARYNGEAL BRANCHES :Are three or four in number. Descend to supply the medial and inferior constrictors of pharynx and the Stylopharyngeus.

PALATINE BRANCH: It passes inward upon the superior constrictor of pharynx, sends ramifications to the soft palate and tonsil, and supplies a branch to the auditory tube.

 PREVERTEBRAL BRANCHES: Are numerous small vessels, which supply the Longi capitis and colli, the sympathetic trunk, the hypoglossal and vagus nerves, and the lymph glands; they anastomose with the ascending cervical artery.

INFERIOR TYMPANIC ARTERY : Passes through a minute foramen in the petrous portion of the temporal bone, in company with the tympanic branch of the glossopharyngeal nerve, to supply the medial wall of the tympanic cavity and anastomose with the other tympanic arteries.

MENINGEAL BRANCHES: Are several small vessels, which supply the dura mater. One, the posterior meningeal, enters the cranium through the jugular foramen; a second passes through the foramen lacerum; and occasionally a third through the canal for the hypoglossal nerve.

TERMINAL BRANCHES

MAXILLARY ARTERYORIGIN:Large terminal branch

given off behind the neck of the mandible.

COURSE:  Divided into three parts by lateral pterygiod muscle.

The first or mandibular portion passes horizontally forward, between the ramus of the mandible and the sphenomandibular ligament, where it lies parallel to and a little below the auriculotemporal nerve; it crosses the inferior alveolar nerve, and runs along the lower border of the lateral pterygiod.

The second or pterygoid portion runs obliquely forward and upward superficial to the lower head of the lateral pterygiod.

  The third or pterygopalatine portion passes between the two heads of the lateral pterygiod and pterygomaxillary fissure,to enter into the pterygopalatine fossa where it lies in front of the sphenopalatine ganglion.

BRANCHES First or Mandibular

Portion Deep Auricular. Anterior Tympanic. Middle Meningeal Accessory Meningeal Inferior Alveolar.

Second or Pterygoid Portion

Deep Temporal. Masseteric. Pterygoid. Buccinator.

Third or Pterygopalatine Portion•Posterior Superior Alveolar.•Infraorbital.•Greater palatine artery•Pharyngeal.•Aretry of pterygiod canal•Sphenopalatine.

FIRST OR MANDIBULAR PART

Deep Auricular Artery (a. auricularis profunda):

-It ascends in the substance of the parotid gland, behind the temporomandibular articulation, pierces the cartilaginous or bony wall of the external acoustic meatus.

-supplies its cuticular lining and the outer surface of the tympanic membrane.

-It gives a branch to the temporomandibular joint.

Anterior Tympanic Artery :

Passes upward behind the temporomandibular articulation, enters the tympanic cavity through the petrotympanic fissure.

- Ramifies upon the tympanic membrane, forming a vascular circle around the membrane with the stylomastoid branch of the posterior auricular, and anastomosing with the artery of the pterygoid canal and with the caroticotympanic branch from the internal carotid.

-Supplies inner surface of tympanic membrane.

MIDDLE MENINGEAL ARTERY (medidural artery):

ORIGIN:A branch of first part of maxillary artery given in the infratemporal fossa. It is the largest of the arteries which supply the dura mater.

COURSE:It ascends between the sphenomandibular ligament and the lateral pterygiod muscle, and between the two roots of the auriculotemporal nerve to the foramen spinosum of the sphenoid bone, through which it enters the middle cranial fossa.

It then runs forward in a groove on the great wing of the sphenoid bone, and divides into two branches, anterior and posterior.

SURFACE MARKING a)Artery enters the skull

opposite to-A point immediately above the middle of the zygoma

b)Artery divides deep to-2cm above the first point

The anterior division can be approached –By making a hole in the skull over pterion, 4cm above the midpoint of zygomatic arch.

The posterior division can be approached –By making a hole at a point 4cm above and 4cm behind the external acoustic meatus.

BRANCHES OF MIDDLE MENINGEAL ARTERYANTERIOR BRANCH OR FRONTAL BRANCH:

Larger than the posterior branch. Crosses the great wing of the sphenoid, reaches the groove, or canal, in the sphenoidal angle of the parietal bone, and then divides into branches which spread out between the dura mater and internal surface of the cranium.

-After crossing the pterion, the aretry is closely related to the motor area of the cerebral cortex.

POSTERIOR BRANCH OR PARIETAL BRANCH: Curves backward on the squama of the temporal bone, and, reaching the parietal some distance in front of its mastoid angle, divides into branches which supply the posterior part of the dura mater and cranium.

 The branches of the middle meningeal artery are distributed partly to the dura mater, but chiefly to the bones; they anastomose with the arteries of the opposite side, and with the anterior and posterior meningeal.

BRANCHES AFTER ENTERING CRANIUM:

(1) Numerous ganglionic branches supply the semilunar ganglion and the dura mater in this situation.

(2) A superficial petrosal branch enters the hiatus of the facial canal, supplies the facial nerve, and anastomoses with the stylomastoid branch of the posterior auricular artery.

(3) A superior tympanic artery runs in the canal for the Tensor tympani, and supplies this muscle and the lining membrane of the canal.

(4) Orbital branches or anastomotic branches pass through the superior orbital fissure or through separate canals in the great wing of the sphenoid, to anastomose with the lacrimal or other branches of the ophthalmic artery.

(5) Temporal branches pass through foramina in the great wing of the sphenoid, and anastomose in the temporal fossa with the deep temporal arteries.

APPLIED ANATOMY FRONTAL BRANCH – Extradural

hemorrhage -hematoma presses on the motor area – hemiplegia of opposite side

APPROACH- hole in the skull over pterion – 4 cm above mid point of zygomatic arch.

PARIETAL OR POSTERIOR BRANCH - contralateral deafness

APPROACH- hole is made 4cm above and 4cm behind the external acoustic meatus.

EXTRADUR HAEMORRHAGE

-Arterial-Symptoms of

cerebral compression occurs late

-Paralysis 1st appears in the face and then spreads to lower parts

-No blood in the CSF

SUBDURAL HAEMORRHAGE

-Venous-Occurs early

-Occurs haphazardly

-Blood in the CSF

Accessory Meningeal Branch (ramus meningeus accessorius; small meningeal or parvidural branch):

It enters the skull through the foramen ovale, and supplies the semilunar ganglion, dura mater and structures in infratemporal fossa.

Inferior Alveolar Artery ( inferior dental artery):

COUSE: Descends with the inferior alveolar nerve to the mandibular foramen on the medial surface of the ramus of the mandible.

It runs along the mandibular canal in the substance of the bone, accompanied by the nerve, and opposite the first premolar tooth divides into two branches, incisor and mental.

The incisor branch is continued forward beneath the incisor teeth as far as the middle line, where it anastomoses with the artery of the opposite side;

The mental branch escapes with the nerve at the mental foramen, supplies the chin, and anastomoses with the submental and inferior labial arteries.

BRANCHESBEFORE ENTERING

MANDIBULAR CANAL: Lingual branch to the tongue. Mylohyiod branch to the mylohyiod

muscle.

WITHIN THE MANDIBULAR CANAL:

Branches to the mandible

Branches to the roots of each teeth upto midline(dental branches)

Incisor branch anastomoses with the branch from opposite side.

AFTER EMERGING FROM MENTAL FORAMEN:

mental branch escapes with the nerve at the mental foramen, supplies the chin, and anastomoses with the submental and inferior labial arteries

BRANCHES OF SECOND OR PTERYGIOD PART  Deep Temporal Branches: two in number,

anterior and posterior, ascend on the lateral aspect of the skull between the Temporalis and the pericranium;

- Supply the muscle, and anastomose with the middle temporal artery;

- Anterior communicates with the lacrimal artery by means of small branches which perforate the zygomatic bone and great wing of the sphenoid.

 Pterygoid Branches: Irregular in their number and origin, supplies the medial and lateral pterygiod.

Masseteric Artery:

- Is small and passes lateralward through the mandibular notch to the deep surface of the Masseter.

-It supplies the muscle, and anastomoses with the masseteric branches of the external maxillary and with the transverse facial artery.

Buccinator Artery ( buccal artery) :

-Is small and runs obliquely forward, between the Pterygoideus internus and the insertion of the Temporalis, to the outer surface of the Buccinator, to which it is distributed, anastomosing with branches of the external maxillary and with the infraorbital.

BRANCHES OF THIRD OR PTERYGOPALATINE PART BEFORE ENTERING PTERYGOMAXILLARY

FISSURE: Posterior Superior Alveolar Artery ( alveolar or

posterior dental artery):

-Is given off, frequently in conjunction with the infraorbital just as the trunk of the vessel is passing into the pterygopalatine fossa.

-Descending upon the tuberosity of the maxilla, it divides into numerous branches, some of which enter the alveolar canals, to supply the molar and premolar teeth and the lining of the maxillary sinus, while others are continued forward on the alveolar process to supply the gums.

APPLIED ANATOMY Site of hematoma during PSA block. Produces largest and most esthetically unappealing

hematoma. Blood effuses until extravascular exceeds

intravascular pressure or clotting occurs. Infratemporal fossa into which bleeding occurs

accommodates large amount of blood. Prevented by aspirating before giving LA in the

site. Digital pressure can be applied medial and

superior to the maxillary tuberosity.

Infraorbital Artery :

ORIGIN:Arises just before maxillary artery enters the pterygomaxillary fissure.

COURSE;It runs along the infraorbital groove and canal with the infraorbital nerve, and emerges on the face through the infraorbital foramen, beneath the infraorbital head of the Quadratus labii superioris.

BRANCHES:

WITHIN THE CANAL

(a) orbital branches which assist in supplying the Rectus inferior and Obliquus inferior.

(b) anterior superior alveolar branches which descend through the anterior alveolar canals to supply the upper incisor and canine teeth and the mucous membrane of the maxillary sinus.

ON THE FACE

a) Branch to the lacrimal sac: some branches pass upward to the medial angle of the orbit and the lacrimal sac, anastomosing with the angular branch of the external maxillary artery.

b) Branch to nose: anastomosing with the dorsal nasal branch of the ophthalmic.

BRANCHES WITHIN THE PTERYGOPALATINE FOSSA:

GREATER PALATINE ARTERY OR DESCENDING PALATINE ARTERY:

Descends through the pterygopalatine canal with the anterior palatine branch of the sphenopalatine ganglion, emerging from the greater palatine foramen, runs forward in a groove on the medial side of the alveolar border of the hard palate to the incisive canal.

The terminal branch of the artery passes upward through incisive canal to anastomose with the sphenopalatine artery. Branches are distributed to the gums, the palatine glands, and the mucous membrane of the roof of the mouth;

While in the pterygopalatine canal it gives off lesser palatine arteries which descend in the lesser palatine canals to supply the soft palate and palatine tonsil, anastomosing with the ascending palatine artery.

APPLIED ANATOMY In case of abscess from

palatal root of first molar,incision should be made in a antero-posterior direction parallel to the artery.

During lefort I osteotomy: Greater palatine artery is easily injured during

oteotomy of the medial or lateral maxillary sinus walls, pterygomaxillary dysjunction or during dwnfracturing of maxilla

The average distance from the piriform rim to the descending palatine artery was 35.4 mm, range is 31 to 42 mm.

The average length of the greater palatine canal above the nasal floor was 10mm, range is 6 to 15 mm.

The average distance between the pterygomaxillary fissure and the greater palatine foramen was 6.6mm

GUIDELINES TO AVOID INJURY:

Oteotomy of lateral wall of maxillary sinus should extend just beyond the second molar.

Osteotomy of medial wall of maxillary sinus should usually extend 30mm posterior to the piriform rim in females,in males it can be carried back to 35mm ---

O’ RYAN Because the descending palatine

artery travels in an anterior-inferior direction as it enters the greater palatine canal ,injury can be prevented by closely adapting the cutting edge of the osteotome or the saw to the pterygomaxillary fissure.

Artery of the Pterygoid Canal (a. canalis pterygoidei; Vidian artery):

- Passes backward along the pterygoid canal with the corresponding nerve.

- It is distributed to the upper part of the pharynx and to the auditory tube, sending into the tympanic cavity a small branch which anastomoses with the other tympanic arteries.

Pharyngeal Branch:

It runs backward through the pharyngeal canal with the pharyngeal nerve, and is distributed to the nasopharynx, the auditory tube and sphenoidal air cells.

  Sphenopalatine Artery (a. sphenopalatina;

nasopalatine artery):

Passes through the sphenopalatine foramen into the cavity of the nose, at the back part of the superior meatus.

-Here it gives off its posterior lateral nasal branches which spread forward over the conchæ and meatuses, anastomose with the ethmoidal arteries and the nasal branches of the descending palatine, and assist in supplying the lateral wall of nose and frontal, maxillary, ethmoidal, and sphenoidal sinuses.

-Crossing the under surface of the sphenoid the sphenopalatine artery ends on the nasal septum as the posterior septal branches;supplies to the nasal septum.

-These anastomose with the ethmoidal arteries and the septal branch of the superior labial; one branch descends in a groove on the vomer to the incisive canal and anastomoses with the descending palatine artery.

LITTLE’S AREA or KIESSELBACH’S PLEXUS

-Near the anteroinferior part or vestibule of the septum.

-Contains anastomoses between Superior labial branch of

facial artery Branch of sphenopalatine

artery Anterior ethmoidal artery Greater palatine artery

This is common site of bleeding from nose or epistaxis.

APPLIED ANATOMY OF MAXILLARY ARTERY Surgeries involving

condyle-Avoid injury to maxillary artery as it lies medial to condyle.

Ankylotic mass of TMJ may encircle the artery.So it is advisable to remove ankylotic mass in pieces rather than in toto.

Trismus involving lateral pterygiod comprises blood supply to the nose.

During Le fort I osteotomy procedure- Pterygopalatine portion of maxillary artery may be injured during fracturing the pterygiod plates if Tessier’s osteotome is directed backwards.

-It should be directed downwards and medially.

Can be used as arterial donor in repair of ICA dissections and aneurysms, due to close proximity of the artery to the cranial base.

Control of epistaxis---If epistaxis is not controlled after nasal packing,it can be controlled by ligating IMA via endonasal , transantral or intraoral approach.

Indications for surgery for control of epistaxis

Continued bleeding despite nasal packing

Nasal anomaly precluding packing

Patient refusal/intolerance of packing

Incision made at the canine mucobuccal fold

Transmaxillary IMA ligation via Caldwell-luc approach

Following an incision into the soft tissue over the maxillary sinus, the bony face of this sinus is exposed.

fenestration of the bony face of the maxillary sinus 

SUPERFICIAL TEMPORAL ARTERYORIGIN: The smaller of the two terminal branches

of the external carotid, appears, to be the continuation of ECA. It begins in the substance of the parotid gland, behind the neck of the mandible.

COURSE: It runs vertically upwards crossing over the root of the zygomatic process

-about 5 cm. above this process it divides into two branches, a frontal and a parietal.

Relations.—As it crosses the zygomatic process, it is covered by the Auricularis anterior muscle, and by a dense fascia; it is crossed by the temporal and zygomatic branches of the facial nerve and one or two veins, and is accompanied by the auriculotemporal nerve, which lies immediately behind it.

BRANCHES Besides some twigs to the parotid gland, to the

temporomandibular joint, and to the Masseter muscle,

its branches are: Transverse Facial. Anterior Auricular. Middle Temporal. Frontal. Parietal

Parietal branch

Frontal branch

Middle temporal artery

Transverse facial artery

Transverse Facial Artery:

ORIGIN:From STA before it leaves parotid gland.

COURSE: Running forward through the substance of the gland, it passes transversely across the side of the face, between the parotid duct and the lower border of the zygomatic arch. This vessel rests on the Masseter, and is accompanied by one or two branches of the facial nerve.

SUPPLIES: The parotid gland and duct, the Masseter, and the integument, and anastomose with the external maxillary, masseteric, buccinator, and infraorbital arteries.

Middle Temporal Artery: Arises immediately above the zygomatic arch, and, perforating the temporal fascia, gives branches to the Temporalis, anastomosing with the deep temporal branches of the internal maxillary artery.

- It occasionally gives off a zygomaticoorbital branch, which runs along the upper border of the zygomatic arch, between the two layers of the temporal fascia, to the lateral angle of the orbit.

-This branch, which may arise directly from the superficial temporal artery, supplies the Orbicularis oculi, and anastomoses with the lacrimal and palpebral branches of the ophthalmic artery.

Anterior Auricular Branches : Distributed to the anterior portion of the auricle, the lobule, and part of the external meatus, anastomosing with the posterior auricular.

Frontal Branch :

Runs tortuously upward and forward to the forehead, supplying the muscles, integument, and pericranium in this region, and anastomosing with the supraorbital and frontal arteries.

Parietal Branch:

Larger than the frontal, curves upward and backward on the side of the head, lying superficial to the temporal fascia, and anastomosing with its fellow of the opposite side, and with the posterior auricular and occipital arteries.

APPLIED ANATOMY Control of temporal

haemorrhage. Anaesthetist’s artery Placement of incisions in

craniotomy In reduction of zygomatic arch

fractures – Gilli’s approach

-A 2cm incision is placed in the temporal region at an angle 45 degree to the zygomatic arch, between two branches of the superficial temporal artery and parallel to the anterior branch.

Anastomoses ICA ECA

Dorsal Nasal Artery and Angular Artery

Dorsal Nasal Artery (branch of the Ophthalmic artery)

Angular Artery (branch of the Facial Artery)

Supraorbital Artery and Frontal Artery

Supraorbital Artery (branch of the Ophthalmic)

Frontal Artery (terminal branch of the Superficial Temporal Artery)

Zygomatico Artery andTransverse facial artery

Zygomatico (branch Lacrimal Artery)

Transverse Facial Artery (branch of Superficial Temporal Artery)

Branches of the Posterior Ethmoidal Artery and branches of the Sphenopalatine Artery

Posterior Ethmoidal Artery

Sphenopalatine Artery(branch of the Internal Maxillary)

Cavernous branches and Middle Meningeal artery

Cavernous branches from the cavernous portion of the ICA

Middle Meningeal Artery (branch of the Internal Maxillary)

ECA -LIGATIONCan be done in carotid triangle or in retromandibular

fossa.

INDICATION:

Bleeding from oral malignancies

Diminishment of blood supply to the area of the tumour bed as adjunctive procedure prior to the tumour resection.

Involvement of vesssel or major branch in tumour

Slipping of superior pedicle of thyriod gland

Injuries causing carotid blow-outs

SPECIAL INSTRUMENTS:

Vascular loops and sutures

Vascular clamps

PATIENT POSITION:

Supine position with shoulder on roll, neck extended and turned to opposite side.

ANAESTHESIA:

GA(local when necessary)

LANDMARKS

1)Upper border of thyriod cartilage

2)Carotid bulb

3)Internal jugular vein

4)Anterior jugular vein

-lower border of mandible

-Anterior border of sternocleidomastiod muscle

Ligation in carotid triangle:

KEY POINTS:

-ICA doesn’t branch in the neck,except for rare exceptions.

-ECA is usually anterior and superficial to ICA but not always.

-Follow the ECA to its 2nd branch,atleast.

-Obtain control of CCA below bifurcation before ligation.

-Be certain that vagus nerve, IJV, hypoglossal nerve and superior laryngeal nerve are identified .

-Bradycardia is common with carotid bulb manipulation.1% lidocaine without epinephrine may be injected into the areolar tissue around bulb.

PROCEDURE INCISION:A horizontal

skin incision is outlined and crosshatched at the level of hyiod bone and submandibular gland,two to three fingerbreadths below the angle of the mandible.It is placed in a skin crease.The posterior border of the incision is over the SCM.

Dissection is carried through skin,platysma,then anterior border of SCM is identified and retracted posteriorly.

A clamp is used to dissect anterior to the muscle parallel to great vessels ,to identify carotid sheath.

The CCA is carefully separated from other contents of sheath.

The IJV, vagus nerve and ansa hypoglossi are retracted posteriorly.

Usually at this place,a vesicular loop is placed loosely around CCA to obtain control.

Then dissection is carried up along the CCA to the bifurcation area.

At this point hypoglossal nerve is identified crossing the branches,it should be preserved.

-ICA doesn’t branch in the neck,except for rare exceptions.

-ECA is usually anterior and superficial to ICA but not always.

-Follow the ECA to its 2nd branch,atleast

-A 2-0 silk tie is placed between the superior thyriod and lingual arteries.

-The wound is closed in layers after the removal of vesicular loop from CCA .

COMPLICATIONS:

-Damage to vital structures.

-Retrograde thrombus formation.

-Persistence of bleeding due to collateral flow.

-Rarely blindness may occur if ophthalmic artery arises from middle meningeal artery of ECA.

LIGATION IN RETROMANDIBULAR FOSSA:

Done when there are maxillary artery injuries.

Skin incision--- at line starting at the tip of mastoid process , circling the mandibular angle, continuing forward below the mandible one inch.

Skin & posterior fibers of platysma are cut, the retromandibular vein or EJV is located, tied & cut.

Branches of great auricular nerve cut -- permit mobilization of cervical lobe of parotid gland.  

Attachment of parotid capsule to the anterior border of sternomastoid severed with scalpel. Parotid gland retracted .

post. Belly of digastric ,stylohyoid muscle is visible. Above this stylomandibular ligament can be palpated if lower jaw of the patient is pulled forward.

This movement--- widens the entrance into retromandibular fossa , tenses the stylomandibular ligament.

Pulsations of ECA are felt , isolated & tied.

EAGLE’S SYNDROME Elongation of styloid process or

ossification of stylohyoid ligament. Mostly arises after tonsillectomy.

SYMPTOMS: Sorethroat,otalgia, glossodynia and

pain along distribution of ICA and ECA.

CAROTID ARTERY SYNDROME Deviated styloid process or ossified

stylohyoid ligament causing impingement on either ECA or ICA

These syndromes cited as DD for atypical facial pain

REFERENCES GRAY’S ANATOMY- 39TH EDITION NETTER’S- COLOUR ATLAS OF ANATOMY B.D.CHAURASIA’S HUMAN ANATOMY-

VOL 3 SURGICAL ANATOMY OF OTOLARYNGOLOGY-JEFFREY

J. BAILLEY JOURNAL OF MAXILLOFACIAL AND ORAL SURGERY-

LOCATION OF DESCENDING PALATINE ARTERY DURING LEFORT I OSTEOTOMY

INTERNET SOURCES

THANK YOU

Guided by Presented by

Dr.S.M.Nooruddin MDS R,Manthru Naik

Dr.K.Surekha MDS

Dr.G.Sudhakar MDS