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Neck dissection Dr. Rajesh Pandey

NECK DISSECTION- A COMPREHENSIVE STUDY

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Page 1: NECK DISSECTION- A COMPREHENSIVE STUDY

Neck dissection Dr. Rajesh Pandey

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Introduction• It is a procedure to remove lymph nodes and surrounding

fibro fatty tissues from neck to eradicate metastasis to cervical lymph nodes in cancer of aerodigestive tract.

• Status of the cervical lymph nodes is the single most important prognostic factor in head and neck tumors.

• Cure rates drop into half when there is regional lymph node involvement

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Emil Theodor KocherEarned Nobel Prize in 1909 for his work in thyroid and neck

surgery — the first ever awarded to a surgeon.

1880 – Kocher proposed

removing nodalmetastases

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1906 – George Crile described the classic radical neck dissection (RND)

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1967 - Bocca and Pignataro described the “functional neck dissection” (FND)

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Subgroups of lymph nodes

• Ia Submental• Ib Submandibular

• IIa Upper jugular (Anterior to XI)• IIb Upper jugular (Posterior to XI)

• III Middle jugular

• IVa Lower jugular (Clavicular)• IVb Lower jugular (Sternal)

• Va Posterior triangle (XI)• Vb Posterior triangle (Transverse

cervical)

• VI Central compartment

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Level I• Submental triangle (Ia)

– Anterior digastric– Hyoid– Mylohyoid

• Submandibular triangle (Ib)– Anterior and posterior

digastric– Mandible.

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Level IAFloor of mouth, anterior oral tongue, anterior mandibular alveolar ridge, lower lip

Level IBOral cavity, anterior nasal cavity, softtissue of midface, submandibular gland

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Level II

• Upper Jugular Nodes• Anterior Lateral border of

sternohyoid, posterior digastric and stylohyoid

• Posterior Posterior border of SCM

• Skull base• Hyoid bone (clinical landmark)• Carotid bifurcation (surgical

landmark)

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• Level IIa anterior to XI

• Level IIb posterior to XI

– Submuscular recess

– Oropharynx > oral cavity and laryngeal mets

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Level IIA & IIBOral cavity, nasal cavity, nasopharynx, oropharynx,, hypopharynx, larynx, parotid gland

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Level III

• Middle jugular nodes– Anterior Lateral border of

sternohyoid– Posterior Posterior border of

SCM – Inferior border of level II– Cricoid cartilage lower border

(clinical landmark) – Omohyoid muscle (surgical

landmark)• Junction with IJV

Level III

Middle jugular nodes• Anterior Lateral border of

sternohyoid• Posterior Posterior border of

SCM • Inferior border of level II• Cricoid cartilage lower border

(clinical landmark) • Omohyoid muscle (surgical

landmark) Junction with IJV

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Level IIIOral cavity, nasopharynx, oropharynx, hypopharynx, larynx

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Level IV

• Lower jugular nodes – Anterior Lateral border of

sternohyoid– Posterior Posterior border of

SCM– Cricoid cartilage lower border

(clinical landmark)– Omohyoid muscle (surgical

landmark)• Junction with IJV

– Clavicle

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Level IVHypopharynx, thyroid, cervical esophagus, larynx

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Level V

• Posterior triangle of neck – Posterior border of SCM– Clavicle– Anterior border of trapezius– Va Spinal accessory nodes– Vb Transverse cervical artery

nodes• Radiologic landmark

– Inferior border of Cricoid– Supraclavicular nodes

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Level VA & VBNasopharynx, oropharynx, posterior scalp/neck skin

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Level VI

Anterior Compartment StructuresBoundaries• Above by Hyoid bone• Below by Suprasternal notch• On either side by medial border

of Carotid sheath

Lymph Nodes– Perithyroidal– Pretracheal– Precricoid Nodes (Delphian)– Paratracheal nodes along

recurrent laryngeal nerves

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Level VIThyroid gland, glottic and subglottic larynx, apex of piriform sinus, cervical esophagus

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Staging of the neck

“N” classification – AJCC (1997)Consistent for all mucosal sites except the nasopharynx

Thyroid and nasopharynx have different staging based on tumor behavior and

prognosis

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Staging

• Nx: Regional lymph nodes cannot be assessed.

• N0: No regional lymph node metastases.

• N1: Single ipsilateral lymph node, < 3 cm

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Staging

• N2a: Single ipsilateral lymph node 3 to 6 cm• N2b: Multiple ipsilateral lymph nodes < 6 cm • N2c: Bilateral or contralateral nodes < 6cm

• N3: Metastases > 6 cm

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Staging

• Nasopharyngeal Carcinoma– N1 – Unilateral < 6cm– N2 – Bilateral < 6 cm– N3a > 6 cm– N3b – Extension to

supraclavicular fossa

• Thyroid– N1 – Regional node mets

• N1a - Ipsilateral• N1b - Bilateral, midline,

contralateral cervical or mediastinal LN

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Classification

Neck Dissection

Comprehensive ND

Radiacal ND

Modified radical ND

Selective ND

Supraomohyoid ND Lateral ND Anteriolat

eral ND

Extended ND

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RND

Structure removed• LN level I – V• SCM• Spinal accessory n.• IJV• Tail of parotid • Submandibular gland• Omohyoid

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Structures to be preserved

Carotid artery Brachial Plexus Phrenic & vagus nerve cervical sympathetic chain marginal mandibular, lingual and hypoglossal nerves

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Modified Radical Neck Excision of same lymph node bearing regions as RND with preservation of one or more nonlymphatic structures (SAN, SCM, IJV)

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MRND Type I

Preservation of SAN

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MRND Type II

Preservation of SAN and IJV

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MRND Type III

Preservation of SAN, IJV, and SCM ( “Functional neck dissection”)

By Bocca

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Selective Neck dissection:

Any type of cervical lymphadenectomy with preservation of one or more lymph node groups

Four subtype:

• Supraomohyoid neck dissection

• Postero-lateral neck dissection

• Lateral neck dissection

• Anterior neck dissection

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Supraomohyoid neck dissection:• Removal of lymph nodes in regions I –III • The posterior limit is the cutaneous branches of the cervical

plexus and posterior border of SCM• The inferior limit is the superior belly of the omohyoid where it

cross IJN

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Selective Neck DissectionsLateral neck dissection– En bloc removal of the jugular lymph nodes

including Levels II-IV.

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SND: Posterolateral Type

• Definition – En bloc excision of lymph bearing tissues in Levels II-IV and additional

node groups – suboccipital and postauricular.

• Indications -Cutaneous malignancies

-Melanoma -Squamous cell carcinoma -Merkel cell carcinoma - Soft tissue sarcomas of the scalp and neck

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SND: Anterior Compartment

• Definition – En bloc removal of lymph structures in Level VI Perithyroidal nodes Pretracheal nodes Precricoid nodes (Delphian) Paratracheal nodes along recurrent nerves

– Limits of the dissection are the hyoid bone, suprasternal notch and carotid sheaths

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Extended Neck Dissection

• Definition– Removal of one or more additional lymphatic groups and/or non-lymphatic structures relatively to a radical neck dissection.eg-level VII, Retro-pharyngeal lymphnode, hypoglosal nerve, carotid artery.

Indication• Carotid artery invasion–Other examples:• Resection of the hypoglossal

nerve resection or digastric muscle

• dissection of mediastinal nodes and central compartment for subglottic involvement, and

• removal of retropharyngeal lymph nodes for tumors originating in the pharyngeal walls

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Indication of RND

• 1. Significant operable neck disease (N2a,N2b, N3) with tumour bulk near or directly involve spinal accessory nerve and/or internal jugular vein/SCM.

• 2.Extensive recurrent disease after previous surgery or radiotherapy.

• 3.Clinical sign of gross extranodal disease

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Indication of MRND

– MRND Type I:1. Clinically obvious neck

lymph nodes metastasis and SAN not involved by tumor

2. Intraoperative decision just like preservation of the facial nerve in parotid surgery

• MRND Type II:1. Rarely planned2. Intra-operative decision for

tumor found adherent to SCM but away from SAN & IJV

• MRND Type III:– Depend on the autopsy

reports1. Lymph nodes were in the

fibrofatty and do not share the same adventitia with blood vessels

2. They are not found within the aponeurosis or glandular capsule of the submandibular “Functional neck dissection”

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• MRND Type III:– For treatment of N0 neck nodes

– Indicated for N1 mobile nodes and not greater than 2.5 – 3.0 cm

• Contra-indicated in the presence of node fixation

• Result is difficult to interpret because of the use of radiation therapy

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• Selective/elective neck dissection:– For treatment of N0 neck nodes

– For N+ nodes when combined with radiotherapy

• Adjuvant radiotherapy for patient with 2 – 4 positive nodes or extra-capsular spread

– Upgrade intra-operatively following positive frozen section

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Indication of SND• SOH TYPE• Is indicated for oral cancer.• T1-T4 with clinical No neck • .indicted for contra-lateral neck in midline

lession of the floor of the mouth or ventral tongue.

• Other indication-extension of parotid surgery, facial skin malignancy anterior to the tragus

• In case antero-lateral part of the tongue level I-IV also be considered.

ANTERIOR COMPARTMENT

• Selected Cases of Thyroid Carcinoma• Parathyroid Carcinoma• Subglottic Carcinoma• CA of Cervical Oesophagus

LATERAL TYPEN0 Neck in carcinomas of• Oropharynx• Hypopharynx• Supraglottis

• Glottic Larynx

POSTERO-LATERAL TYPECutaneous malignancies

• Melanoma• SCC• Merkell cell Carcinoma

- Soft tissue sarcomas of scalp and neck

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• Indication and the type of ND, specially for N0, is controversial

• The following surgical outline was suggested:– SCC oral cavity anterior to circumvalate papilla

• Supraomohyoid– SCC Oropharynx, larynx and hypopharynx

• level I- IV or level II-V– SCC with N+ nodes

• RND – SCC with 2-4 positive nodes or extracapsular spread

• RND and adjuvant therapy

Shah Cancer July 1;109-113: 1990

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N+ disease needs Comprehensive neck

dissection

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Contra-indication

• 1.Untreatable primary tumour or unresectable neck disease(i.e-encasement of brachial plexus, internal carotid artery, prevertebral fascia.

• 2.Patient unfit for major surgery

• 3.Simaltaneous bilateral neck dissection

• 4. Distant metatases

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PREOPERATIVE PREPARATION

1. Ensure all documentation, preoperative procedures, and orders are complete.

2. Check the surgical consent form and others for completeness.

3. Document allergies.

4. Document height and weight.

5. History and Physical.

6. Baseline vital signs.

7. Ensure results of all laboratory and diagnostic tests are on the chart. Document and report any abnormal results.Report special needs and concerns.

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Basic needs of an incision are:

1.Good exposure of the neck and primary disease.

2. Ensure viability of the skin flaps. Avoid acute angles

3. Protect carotid artery even in the cases of wound infection

4.Considered preoperative factor—previous radio or chemotherapy. 5. When draping the surgical field the following ipsilateral landmarks

should be visible 6.Mastoid tip., Ear lobule, Body of the mandible, midline of the chin,

supra-sternal notch, clavicle and region of trapizius muscle insertion

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“Surgical approach”

Incisions

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A p r o n I n c i s i o n

INCISION TYPES

Freeland and Rogers (1975) suggest that the incisions that are most likely to safeguard the blood supply to the skin flaps are the superiorly based apron like.• incision from mastoid to mentum

designed by Latyschevsky and Freund (1960) for combined neck dissection with intraoral procedures

• Apronlike incision described by Freund (1967) to be used when a neck dissection is performed in conjunction with a laryngectomy

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H a l f A p r o n I n c i s i o n

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C o n l e y I n c i s i o n

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Y - I

n c

i s

i o n

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D o u b l e – Y I n c i s i o n

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H - I n c i s i o n

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M a c F e e I n c i s i o n

• 1st limb begins over mastoid process goes down to hyoid bone then up again to the point of chin.

• 2nd limb lies 2cm above the clavicle.It start laterally at ant border of tepezius and and medially at the midline

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S c h o b i n g e r I n c i s i o n

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M o d i f i e d S c h o b i n g e r

I n c i s i o n

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0ther incision

J incision Lateral Utility incision Lahey’s

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Steps of Radical Neck Dissection

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Good Incision

• 1.Good exposure of the neck and primary disease.

• 2. Ensure viability of the skin flaps. Avoid acute angles

• 3. Protect carotid artery even in the cases of wound infection.

• 4. Facilitate reconstruction Example, if pectoral muscle is used a lower limb should be near the clavicle to enable flap accommodation.

• 5. It should be cosmetically acceptable.

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4 area of special attention• Lower end of IJV

• Junction of lateral border of clavicle with lower edge of trapezius

• Upper end of IJV

• Submandibular triangle

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Critical steps in RND-lower neck

• Divide the lower end of the SCM muscle in the first area.• Isolate and ligate the Internal jugular vein• Look for and avoid damage to the thoracic duct and branches of the

jugular lymphatic duct in chaissaignac ‘s triangle• Remove scalene nodes• Devide and retract OM ms upwards.• Mobilize the fat pad overlying prevertebral fascia• Identify and preserve brachial plexus• Identify and preseve the phrenic nerve• Deal with 2nd area

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Critical steps in RND-upper neck

• Divide the upper end of SCM in 3rd area

• Retract the post belly of digastric muscle upward

• Identify and ligate IJV

• Identify and preserve hypoglossal n.

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1st area-lower end IJV • Lower end of IJV is approached 1st by continuing dissection along upper boder of

clavicle from trapezius to suprasternal notch• Supra clavicular n and vessel divided• IJV lies between sternal and clavicular head of SCM .Divide ms fibre reveal vein• Carotid sheath opened , IJV exposed few cm ligate with 3 suture( vicry 0-0) and

transfixed at lower end taking care vagus n.• Left side dissection thoracic duct passes medial to IJV then post finally curve

around it and enter the jn of IJV and subclavian v.• Rt side similar but smaller duct ( accessory duct) encouter• Once IJV tied dissection extends laterally upward towards chaissaignac

triangle( b/w scalenus ant attach to tubercle of c6 , subclavian Ar base)• Remove scalene nodes .• Main jugular lymph duct that terminate on left side with thoracic duct risk if

damage . Found source and transfixed

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2nd area – Jn of Clavicle and Ant. border of Trapezius

• Begin dissection at lower end of trapezius.• The fatty tissue in supraclavicular region are divided.• While the fat is retracted upwards, the inferior belly of omohyoid muscle is

encountered.• It is either cut or ligated and then it can be retracted upwards.• Deeper to omohyoid, transverse cervical artery and vein found , run laterally

across floor of post triangle is ligated which may be a source of bleeding during dissection of posterior triangle.

• Dissection continued till prevertebral fascia—Phrenic nerve and brachial plexus protectrd.

• Phrenic n. descends from lateral to medial through the neck over the ant scalenus ms and brachial plexus emerges from between medial and ant scalenus ms.

• Supraclavicular dissection is continued to ant border of trepizius and dissection continue in upward direction to dissect post triangle.

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Dissection of posterior triangle

• Following the ant border of trapezius but dissecting on the prevertebral fascia the post triangle is cleared. Prevertebral fascia left intact.

• Acessory n. is identified before dissection of post. triangle . Nerve run in the floor of post triangle.

• Methods of identification of acessory n. It exists the lat border of SCM at Jn of upper 1/3 and lower 2/3 and then

has sinuos course before arriving at lower ant border of trepizius to supply this ms.

At the exist from sternomastoid , 1cm above Erb’s point where nerve winds around the ms on its way to supply the parotid fascia.

Dissect up ant border of trapizius in post triangle until nerve is encounter ( confused with with branches of B. plexus.

Drow line lat from laryngeal prominence through post triangle, n crosses that line as it run from erb’s point to the lower post corner of post triangle.

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Dissection of posterior triangle

• Attempt to preserve shoulder ( preserve C3 , C4 n) even if acessory n divided.

• Dissection continue up to mastoid tip

• SCM ms at upper end divided under tension by pulling down • The level of transection is at angle of jaw include lower pole of parotid.

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3rd Area-Upper end of IJV

• Using langenbech retractor under post belly of digatric ms (resident’s friends), upper end of IJV identified

• Its position may be located by palpating transverse process of C2

• Vein is mobilise using lehey forcep , nonabsorbable suture 2 above and 1 below to point of division along with transfixing suture.

• Before tying any ligature ,vagus and hypoglossal n identified and preserved

• Vagus n run along ICA and CCA. Hypoglossal n run across carotid bifurcation.• Remember- all branches of IJV arise from antero-medial surface ligated

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4th area- submandibular triangle

• Dissection begin in the midline• Fat is divided in submental area , display ant belly of DG ms.• Ant. Part of submandibular gland is then idintified and dissected to the

post border of mylohyoid • Upper border of submandibular gland freed by dividing and tying the

vessel including the facial artery• Mylohyoid ms retracted in forward direction to reveal the submandibular

duct. At this point lingual n. is is pulled down in a curve.• Lingual gives small but const branch to SM ganglion, divided • SM duct is tied and divided , taking hypoglossal n in direct vision • Specimen is removed following transfixion and division of facial artery as

it winds over post border of DG ms at post-inf border boder of SM gland.

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summarySubplatismal flap elevation with external jugular vein and greater auricular nerve overlying the SCM

Transecting the sternal head of the SCM

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The supraclavicular nerves Exposing the IJV by incising the carotid sheath

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Anteriorly based flap elevated to expose the omohyoid and SCM

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The lesser occipital nerve (C2) can be confused with the XIn

Free the XIn and divide its branches to SCM

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Spinal Accessory Nerve

• CN XI – Relationship with the IJV

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XIn passing through the IJV

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Posterior flap fully elevated to the trapezius muscle

The XIn is located 1-2cm behind the greater auricular nerve

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Posterior flap fully elevated to the trapezius muscle

The XIn is located 1-2cm behind the greater auricular nerve

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Clossure• The neck is irrigated with water • 2 suction drain(12 fz) is inserted.drai should never cross

carotid sheath.• Anaesthetist ask to perform a valsalva manoeuvre to check

chylous leak and bleeding.• The neck is closed in layers with continuous vicryl to platysma

and sutures/staples to skin • The drain is maintained on continuous suction e.g. low

pressure wall suction, until the drainage volume is <50ml /24hrs

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COMPLICATIONS

• Air embolus• HAEMORRAGE• Carotid blowout• Carotid sinus syndrome• Pneumothorax• Chyle leak & Chylus fistula• Increased intracranial pressure• Wry Neck (Torticollis Coli)• Shoulder dysfunction• Cerebral oedema

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