APPLIED SURGICAL ANATOMYOF ARTERIES OF HEAD AND NECK : APPLIED SURGICAL ANATOMYOF ARTERIES OF HEAD AND NECK DEEPTHA.J Arteries of head and neck : Arteries of head and neck Aorta
Common carotid artery
External carotid artery
Internal carotid artery
Subclavian artery COMMON CAROTID ARTERY : COMMON CAROTID ARTERY COURSE – The right common carotid artery arises from the brachiocephalic artery behind the sternoclavicular joint.
-- The left artery arises directly from the arch of aorta behind the manubrium sternum.
-- In the neck, each CCA extends upwards & laterally with in the carotid sheath to the level of upper border of lamina of thyroid cartilage.
-- The bifurcation takes place in carotid triangle opposite the disc between c3 & c4 vertebra. VARIATIONS OF CCA : : VARIATIONS OF CCA : In 12% subjects right CCA arises above the level of upper border of sternoclavicular joint.
May arise as a separate branch from arch of aorta, or in conjunction with left CCA.
In majority of abnormal cases left CCA arises in common with brachiocephalic artery , if that artery is absent , two carotids arise by single trunk.
Rarely artery ascends in the neck without undergoing division, either ECA or ICA being absent.
CCA usually has no branches ,but may give origin to vertebral, superior thyroid, ascending pharyngeal, inferior thyroid or occipital artery. APPLIED ANATOMY : APPLIED ANATOMY CAROTID PULSE : CCA may be compressed against the carotid tubercle of transverse process of C6 vertebra ( carotid tubercle of chassaignac ) about 4cm above the sternoclavicular joint.
Patency of carotid system can be investigated by angiography by injecting a contrast medium into CCA. EXTERNAL CAROTID ARTERY : EXTERNAL CAROTID ARTERY Anterior : Superior thyroid
Medial: Ascending pharyngeal
Superficial temporal EXTERNAL CAROTID ARTERY : EXTERNAL CAROTID ARTERY Introduction:
It lies anterior to ICA and is the chief arterial supply to structures in front of neck and face.
Under cover of anterior border of sternocleidomastoid Course : : Course : As the artery ascends ,it passes deep to the post. Belly of digastric and stylohyoid muscle and enters the parotid gland where it inclines somewhat backwards n lies lateral to the ICA.
Italic ‘f’ shaped course from commencement to termination. At the origin - Artery lies in the carotid triangle,
antero medial to ICA. APPLIED ANATOMY : APPLIED ANATOMY LIGATION OF ECA :
Done at 2 points
Artery exposed at its origin & ligature above superior thyroid artery – upper part of neck, superficial & deep structures of neck
Ligation higher up, behind the angle of lower jaw- maxillary artery injuries
UNILATERAL LIGATION – will not stop hemorrhage : A] LIGATION OF ECA IN CAROTID TRIANGLE:- Skin incision-- at the level of angle of mandible behind anterior border of sternocleidomastoid muscle ,continued downward to the level of cricoid cartilage. -- Platysma, superficial sheath of sternomastoid incised, muscle exposed & retracted ,deep layer of sternomastoid head is visible & IJV through it.
-- Fascia in front of vein is cut to expose the arteries. Slide 11: LIGATION IN RETROMANDIBULAR FOSSA :
Skin incision--- at line starting at the tip of mastoid process , circling the mandibular angle, continuing forward below the mandible one inch.
Passing scalpel through skin & posterior fibers of platysma , the retromandibular vein or EJV is located, tied & cut.
Branches of great auricular nerve cut -- permit mobilization of cervical lobe of parotid gland. Slide 12: 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. 1. SUPERIOR THYROID ARTERY : 1. SUPERIOR THYROID ARTERY COURSE: arises from the front of ECA below the tip of greater cornu of hyoid bone, passes downward and forward accompanied by the laryngeal nerve.
Rests on the inferior constrictor muscle, passes deep to omohyoid ,sternohyoid, sternothyroid and reaches the upper pole of lateral lobe of thyroid. APPLIED ANATOMY: : APPLIED ANATOMY: The arch of superior thyroid artery is characteristic – diagnostic landmark
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. 2. LINGUAL ARTERY : 2. LINGUAL ARTERY Introduction: Principal artery of tongue. Arises from front of ECA opposite the tip of greater cornu of hyoid bone.
Sometimes arises in common with facial artery as a ‘linguo-facial’ trunk.
Divided into 3 parts by hyoglossus muscle. Slide 16: FIRST PART – In carotid triangle, extends from origin to the posterior border of hyoglossus.
Rests on the middle constrictor, crossed by hypoglossal nerve.
SECOND PART – Deep to hyoglossus, runs horizontally forward along the upper border of hyoid bone between hyoglossus laterally and middle constrictor, stylohyoid ligament medially. Slide 17: THIRD PART – [ ‘arteria profunda linguae’ ],ascends along the anterior Border of hyoglossus, then horizontally forward on the undersurface of tongue on each side of frenum linguae.
In vertical course, lies b/t the genioglossus medially & inferior constrictor of tongue laterally. Horizontal part is accompanied by lingual nerve. Applied anatomy : Applied anatomy In surgical removal of tongue , first part of artery is ligatured before it gives any branches to the tongue or tonsil. Slide 19: 2] sublingual artery -- injury occurs in premolar & molar region, when sharp instrument or rotating disks slips off a lower molar & injure the floor of mouth. LIGATION OF LINGUAL ARTERY : : LIGATION OF LINGUAL ARTERY : Incision – circling the lower pole of submandibular gland.
Posterior part – towards tip of mastoid ; anterior part – towards chin.
Skin, platysma, deep fascia incised, submandibular gland exposed , lifted,tendon of diagastric visible.
Free border of mylohyoid muscle ascertained, 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. 3.Facial artery : 3.Facial artery Arises from the ECA just above the tip of greater cornu of hyoid bone
Runs upwards -- neck as cervical part ; face -- facial part.
Tortuous course—allows free movements of pharynx during deglutition, on face -- free movements of mandible , lips, & cheek during mastication & facial expressions, escapes traction & pressure during movements. Course: Cervical part : Course: Cervical part Runs upwards on superior constrictor of pharynx deep to the, posterior belly of digastric with stylohyoid & to the ramus of mandible
Grooves the posterior border of submandibular gland
Makes S-bend [2 loops] 1st winding down over submandibular gland & then over the base of mandible. VARIATIONS : : VARIATIONS : May arise in common with lingual artery constituting “linguo-facial trunk”.
Occasionly ends by forming submental artery& not infreqently extends only as high as the angle of mouth or nose.
Deficiency is compensated by enlargement of one of neighbouring arteries. Slide 24: 3] facial artery – 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. LIGATION OF FACIAL ARTERY. : 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.
Artery is accompanied by facial vein & crossed superficially by marginal mandibular branch of facial nerve.
Taking this into consideration, incision -- at least half inch below the border of mandible & parallel to it.
Skin, platysma, deep fascia are cut , soft tissues retracted, pulse of facial artery felt.
Artery-- isolated, tied & cut. OCCIPITAL ARTERY : OCCIPITAL ARTERY Arises in carotid triangle from posterior aspect of ECA .
Passes backward, upward along & under cover of post. Belly of diagastric , crossing superficial to contents of carotid sheath, hypoglossal & accessory nerve. Appears in the sub occipital region , rests on the rectus capitis ,obliqus capitis superior &semispinalis capitis, crosses the apex of post. triangle of neck, finally piercing trapezius. BRANCHES: : BRANCHES: 1]Sternomastoid branch – two in no., supply sternomastoid m.
2]mastoid branch –enters cranial cavity through mastoid foramen, supplies mastoid air cells in the dura.
3]meningeal branch – enters the skull through jugular foramen & condylar canal, supplies dura of posterior cranial fossa. Slide 28: 4] muscular branch- supply adj. muscles.
5]occasional auricular branch supplies cranial surface of auricle.
6]descending branch- superficial --anastamoses with sup.br. Of transverse cervical art.; deep br.anastamoses with deep cervical art.
7]occipital br. – supply the scalp upto vertex. APPLIED ANATOMY : 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 ( costo-cervical trunk )
ECA * SCA
Important for neurosurgeons ASCENDING PHARYNGEAL ARTERY: : ASCENDING PHARYNGEAL ARTERY: First, smallest, medial br. Of ECA.
Ascends to base of skull between wall of pharynx & ICA.
Branches –pharyngeal, tympanic, meningeal. Slide 31: Pharyngeal br. –supply wall of pharynx,tonsil,part of auditory tube,& soft palate.
Inferior tympanic branch –supply medial wall of tympanic cavity.
Meningeal br. –supply dura matter & adj. bones. Slide 32: 32 Maxillary artery Origin – larger terminal branch of external carotid, arises behind and below the mandibular neck, in substance of parotid gland
Pterygopalatine part Slide 33: 33 Mandibular part ( first part) Passes between the mandibular neck and the sphenomandibular ligament, below auriculotemporal nerve
Deep auricular artery
Anterior tympanic branch
Middle meningeal artery
Frontal & Parietal
Accessory meningeal artery
Inferior alveolar artery Slide 34: 34 Pterygoid part (Second part) Ascends obliquely forwards medial to temporalis and superficial to lower head of lateral pterygoid
Deep temporal branches
Buccal artery Slide 35: 35 Pterygopalatine part Passes between the heads of lateral pterygoid, through pterygomaxillary fissure into the pterygopalatine fossa
Artery of pterygoid canal
- Sphenopalatine artery APPLIED SURGICAL ANATOMY : APPLIED SURGICAL ANATOMY MIDDLE MENINGEAL ARTERY ( 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
MMA ( parietal or posterior branch )- contralateral deafness
APPROACH- hole is made 4cm above and 4cm behind the external acoustic meatus. Slide 37: POSTERIOR SUPERIOR ALVEOLAR ARTERY- site of hematoma during PSA block.
- prevented by aspirating before giving LA in the site.
GREATER PALATINE AND ANTERIOR PALATINE ARTERY.
case of abscess from palatal root of first molar,incision should be made in a antero-posterior direction ,then transversly.
Incision– made near free margin of gingiva.
Edge of knife directed outward, upward. Slide 38: 38 Superficial temporal artery Origin: smaller of the two terminal branches, begins in the parotid gland behind mandible’s neck
Course: crosses the posterior root of zygomatic process of temporal bone, divides into anterior and posterior branches APPLIED ANATOMY : 39 APPLIED ANATOMY Control of temporal haemorrhage
Anastomose freely; partially detached with scalp also heal with reasonable hope even if one vessel is intact
Placement of incisions in craniotomy
In reduction of zygomatic arch fractures – Gilli’s approach COLLATERAL CIRCULATION : COLLATERAL CIRCULATION In occlusion of CCA -- anastamoses between branches of SCA & ECA.
Achieved through :1] Br. Of Right & left ECAs.,
2] between left & right ICA via circle of willis.
3] superior thyroid A. with inferior thyroid A.
4] descending branch of occipital A. with deep cervical & asc. Branch of transverse cervical A.
5] vertebral A. may take over entire supply of carotids with in skull. APPLIED ASPECT OF ARTERIES : : APPLIED ASPECT OF ARTERIES : A] Arteries endangered during minor surgical procedures or dental treatment :
1] anterior palatine artery :
2. sublingual artery
3. facial artery B] ARTERIES ENDANGERED DURING ORTHOGNATHIC SURGERIES : : B] ARTERIES ENDANGERED DURING ORTHOGNATHIC SURGERIES : Pterygopalatine portion of maxillary artery – during Le fort I osteotomy procedure
In mandibular orthognathic surgery, collateral blood supply is central to preservation of osteotomised segments.
Carotid A. may be susceptible to damage during orthognathic surgery.
Thrombosis of ICA can occur after surgery due to excessive extension of head & neck. PROTECTION OF MAJOR BLOOD VESSELS: : PROTECTION OF MAJOR BLOOD VESSELS: Vessels requiring special protection during & following neck dissection are carotids, common & internal.
Rupture of carotid system is reffered as ‘carotid blow-out’.
Common adverse circumstance– previous exposure to ionising radiation. Slide 44: Vessel damaged by radiotherapy is subjected to added insult of wound breakdown & exposure, & liable to rupture.
Two methods of protecting:
Modified skin incisions
Covering of vessels using muscle flaps or graft of dermis. MODIFICATIONS OF SKIN INCISIONS : : MODIFICATIONS OF SKIN INCISIONS : MacFee INCISION – Most widely used. The sites where hazard remains are points at which the transverse suture lines ,upper & lower ,cross the line of artery.
Upper more vulnerable, as likely to be site of salivary fistula or wound breakdown .
CONLEY INCISION – also provides excellent protection for vessels below level of hyoid.
HAYES MARTIN INCISION. VESSEL COVERING : : VESSEL COVERING : -- Transected at a suitable level above the clavicle , mobilised & swung anteriorly to cover the area of carotid bulb.
-- myocutaneous flaps --- standard techniques in intraoral reconstruction. 1]MUSCLE FLAPS – They carry their blood supply with them in transfer.
- the group of muscles behind the carotids , scalenes & levator scapulae are used for cover.
Most effective flap – levator scapulae. DERMAL GRAFTS : : DERMAL GRAFTS : Alternative method of protection.
Standard split skin graft used,removing a strip of underlying dermis & replacing the skin graft in its original site.
Dermal strip along entire length of carotid provide extra layer of protective collagen. Slide 48: END OF PART 1 THE SUBCLAVIAN SYSTEM OF ARTERIES : : THE SUBCLAVIAN SYSTEM OF ARTERIES : ORIGIN - Arises from the brachiocephalic trunk. Left subclavian art.arises from the arch of aorta. BRANCHES OF SUBCLAVIAN : BRANCHES OF SUBCLAVIAN a) vertebral,
b) internal thoracic
c) thyrocervical trunk.
d) costo cervical trunk.
e)Dorsal scapular artery. Course: : Course: Cervical part -- curved course with upward convexity.
extends from the sternoclavicular joint to the outer border of first rib, enters through the apex of axilla & continued as axillary artery.
Each art. Arches over the cervical pleura n apex of the lung, subdivided into 3 parts by scalenus anterior muscle
,1st part -- upto medial border of muscle, 2nd part--- behind the muscle, 3rd---- lateral border of muscle to the outer border of 1st rib. VARIATIONS : : VARIATIONS : Right SCA may arise from brachiocephalic artery above or below the level of sternoclavicular joint.
May be a separate trunk from arch of aorta, & then be either first or last branch.
When first branch– occupies ordinary position of brachiocephalic trunk.
When last branch –arises from left extremity of arch , ascends obliquely at right side behind trachea , esophagus, & right CCA to inner border of first rib. : Occasionly it perforates scalenus anterior, rarely passing in front of muscle.
May ascend as high as 4cm above the clavicle or only reach the upper border of bone.
Left SCA is occasionly joined at its origin with left CCA. APPLIED ANATOMY : APPLIED ANATOMY Subclavian steal syndrome -- takes place in obstruction of SCA proximal to the origin of vertebral artery. Some amount of blood is stolen from the brain through the vertebral artery of the opposite side in order to provide collateral circulation to the affected arm. This may result in ischemic neurological symptoms. Effective compression of SCA can be attained only where it passes across the upper surface of 1st rib. To compress the vessel here, the shoulder should be depressed & pressure exercised downwards, backwards &medially in the angle formed by the posterior border of the sternocleidomastoid with the upper border of clavicle. : A cervical rib may compress the SCA, diminishing the radial pulse.
An aneurysm may form in the 3rd part of SCA.its pressure on the brachial plexus causes pain, weakness,& numbness in the upper limb.
The rt. SCA may arise from the descending thorasic aorta. In that case , it passes posterior to oesophagus which may be compressed, condition known as dysphagia lusoria.
Cervical rib may compress the subclavian artery. Here the radial pulse is diminished or obliterated on turning the patients head upwards and to affected side after deep breath- ADSONS TEST. Slide 56: BLALOCK S operation for fallots tetrology – right subclavian artery is anastomosed end to side to short circuit to pulmonary stenosis VERTEBRAL ARTERY : : VERTEBRAL ARTERY : Origin-- from the upper surface of the first part of SC A.passes through-- foramina transversaria of upper six cervical vertebrae, winds backward around the lateral mass of atlas,enters the cranial cavity through foramen magnum, and at the lower border of pons. unites with similar artery of opposite side forms-- the basilar artery. BRANCHES: : BRANCHES: A]Cervical branches –
1] spinal branches – enter the vertebral canal through intervertebral foramina ; supplies spinal cord,meninges, vertebra.
2] muscular branches – from 3rd part ; supply sub-occipital muscles.
B] cranial branches –a) meningeal branches b)posterior spinal artery,
c)ant. Spinal artery.,d) post. Inferior cerebellar artery, e)medullary arteries. Parts : Parts First part:- extends from the origin of the artery to the transverse process of c6.
Runs upwards and backwards in the triangular space b/w scalenus anterior and longus colli muscles called vertebral triangle
Second part– runs through the foramina transverseria of upper C6.it course is vertical upto the axis vertebrae Slide 60: Third part :Lies in the sub-occipital triangle emerging from foramen tranversarium of atlas.
Enters the vertebral canal by passing deep to the lower arched marginof the posterior atlanto-occipital membrane .
Fourth part :Pierces the dura & arachnoid maters,& passes upward & medially through the foramen magnum in front of first tooth of ligamentum denticulum.
At lower border of pons ,it unites with the fellow of opp. Side to form basilar art. INTERNAL THORACIC ARTERY : INTERNAL THORACIC ARTERY Arises from the inferior surface of 1st part of SCA, opposite the origin of thyrocervical trunk.,2cm above the sternal end of clavicle.
Ant. Inter-costal artery.
Superior epigastric artery. THYRO CERVICAL TRUNK : THYRO CERVICAL TRUNK Arises from the upper surface of 1st part of SCA,just distal to the origin of vertebral art.
3 branches : 1]inferior thyroid art.
-a]asc. Cervical art.
-b]inf laryngeal art.
-c]tracheal, oesophageal, laryngeal br.
2]superficial cervical art.
3]suprascapular art. COSTO-CERVICAL TRUNK : COSTO-CERVICAL TRUNK Arises from the back of 1st part of SCA on left side2nd part of same art. On rt. Side.
Branches – 1]deep cervical artery
--2] superior intercostal art. DORSAL SCAPULAR ARTERY : DORSAL SCAPULAR ARTERY Arises from 3rd part of SCA.
Passes laterally b/w upper & middle or middle & lower trunks of bracheal plexus.
supply the rhomboids & enters in formation of scapular anastamoses. BRANCHES OF ICA : BRANCHES OF ICA From petrous part –
2] branches to pterygoid canal.
From cavernous part –
3] inferior hypophysial artery.
4] meningeal branch.
From cerebral part –
5]superior hypophyseal artery.
7] posterior communicating artery.
8] anterior choriod artery.
9] anterior cerebral artery.
10] middle cerebral artery. Slide 66: 66 Internal carotid artery Origin - similar to that of ECA
Course- broadest outline
Vertically upwards – neck
Horizontally forwards and medially- petrous carotid canal
Upwards – foramen lacerum
Horizontally forwards – cavernous sinus
Vertically upwards medial- anterior clinoid process
Backwards and upwards – to its terminal branches Slide 67: 67 Divided into-
Cerebral Internal carotid artery Slide 68: 68 Cervical part Relations
Posteriorly -sup cervical ganglion,sup laryngeal nerve
Medially - ascending pharyngeal artery
Anterolaterally - sternocleidomastoid muscle
Inferiorly-digastric, hypoglossal nerve
At the level of digastric - stylohyoid muscle, posterior branches of ECA
Above the digastric - styloid process,deeper part of parotid gland Internal carotid artery Slide 69: 69 Petrous part Relations
Surounded by venous and sympathetic plexuses
Posterolaterally-middle ear and
Anterolaterally- auditory tube
ganglion Internal carotid artery Slide 70: 70 Branches
Caroticotympanic branch or artery
Pterygoid artery Internal carotid artery Slide 71: 71 Cavernous part Ascends to the posterior clinoid process
Emerges through the dorsal roof of the cavernous sinus
Meningeal branches Internal carotid artery Slide 72: 72 Cerebral part Lies at base of the brain.Divides into Anterior and Middle cerebral arteries.
Gives off 5 branches:
Anterior cerebral artery
Middle cerebral artery
Posterior communicating artery
Anterior choroid artery Internal carotid artery Slide 73: 73 Ophthalmic artery Artery enters the orbit through optic canal.
Terminates near the medial angle of the eye, dividing into supratrochlear and dorsal nasal branches Internal carotid artery Slide 74: 74 Branches
Central artery of retina
Posterior ethmoidal artery
Anterior ethmoidal artery
Medial palpebral artery
Supratrochlear artery Ophthalmic artery Slide 75: end Slide 76: 76 Circle of Willis Circulus arteriosus – polygonal
Anterior cerebral arteries through
anterior communicating arteries
Posterior cerebral arteries each joins the ipsilateral internal carotid artery by a posterior communicating artery