1.
Neck dissection(2731)
In 1906 Crile describe the classic radical neck dissection & populalized by Hayes Martin. The
following neck dissection can be performed.
Classic radical neck dissection;
Extended radical neck dissection;
Modified radical neck dissection (type 1-3);
Selective neck dissection.
Preoperative preparation;
A unilateral neck dissection doesnot require a tracheostomy but it is advised to have an
tracheostomy for a patient who is undergoing a bilateral or a 2nd dissection following previous
radiotherapy.
Position
The patient is intubated & laid supine with the head extended on a head ring, sand bag under the
shoulders &head turned to the opposite side. By placing the sand bag more on the ipsilateral
side,the dissection of the posterior triangle is more easier.
Incision;
There are a number of incisions available to perform a neck dissection. The decision will be based on
personal preference, previous surgery, number of levels required for access purposes, any previous
surgical incision & the site of the primary tumour.
If the patient has not previous been irradiated, the commest used incision is the Y type (crile) or
schobinger incision with a lazy S on the vertical limb to reduced scar tissue contracture.
If the patient has been irradiated ,two separate incisions described by McFee, has limited access . so
horizontal-T (Hetter) & utility incision.
Other incision are lateral utility, visor , extended thyroid ,H-incision.
Radical neck dissection
This removes the lymph node containing levels in the neck (I-V) & all three nonlymphatic structures
(spinal accessory nerve, sternomastoid, & internal jugular vein).
Indications
Significant operable neck disease (N2a,N2b,N3)
Access prior to pedicle flap reconstruction.

2.
Contraindications
Those patients whose primary tumour are untreatable,those who are unfit major surgery, those with
distant metastases.
Raising the flaps
Major corners of consternation
-Lower end of internal jugular vein
- junction of lateral border of clavicle with the lower edge of trapezius.
-Upper end of internal jugular vein.
-submandibular triangle.
Minor corners consternation
Retropharyngeal nodes
Parapharyngeal nodes
Chaissaignac’s triangle.
Lower end of the internal jugular vein
It is by convention , usual to begin at the lower end in the first corner of consternation.It is the basic
principle of cancer surgery that the main vein draining the primary tumour being removed should be
divided first.This steps may reduce the number of systemic metastases.Lower end of IJV is
approached by dividing the sternomastoid muscle.
Carotid sheath is opened to expose the internal jugular vein & it is important to identify a length of
at least 2cm to ligation.Three ligatures are used , two at the lower end & one at the upper end. In
addition ,both end of veins are transfixed.
Once the internal jugular vein has been tied ,the dissection extends laterally to approach
Chaissaignac’s triangle(longus coli & scalenus anterior ,their attachments to the tubercle of C6 &
subclavian artery is the base.)
The critical steps in radical neck dissection of the lower neck are as follows;
1)Divided the lower end of sternomastoid in corner 1.
2) Isolate & ligate the internal jugular vein.
3) Look for & avoid the thoracic duct & branches of the jugular lymph duct in chaissaignac’s triangle.
4) Divided & retract the omohyoid muscle upwards.
5)Mobillize the fat pad overlying the prevertebral fascia.
6) Identify & preserve the brachial plexus & phrenic nerve.

3.
7)Deal with corner 2.
Supraclavicular dissection(corner 2)
The dissection proceeds towards corner 2 at the lateral end of the clavicle& this is done by
supraclavicular dissection.One tric is to tie off the internal jugular vein & then go straight to the
bottom end of the trapezius ,begin dissection behind the omohyoid from lateral to medial. Omohoid
muscle is divided. Then phrenic nerve is identified, it runs over sclanius anterior from lateral to
medial.
Dissection of the posterior triangle
This dissection continued up the anterior border of trapezius to the mastoid tip.
Most important structure is accessory nerve that runs in the roof ,not the floor of the posterior
triangle,It exits the lateral border of the sternomastoid at the junction of its upper1/3 &lower 2/3.
(Erb’s point), can be identified the nerve 1 cm above the point of the great auricular nerve winds
round the muscle. Another way of finding the nerve is to draw a line laterally from the laryngeal
prominence through posterior triangle. It crosses the Erb’s point.
The dissection continues , dividing the fascia from anterior border of trapezius up to mastoid tip
where the sternomastoid joins with the trapizus. If the accessory nerve is involved then it is not wise
to preserve it.Firm traction is applied to sternomastoid muscle ,the level of trisection is at the angle
of the jaw &would normally include the lower pole of parotid gland. This would facilitate ligation of
upper end of IJV.
Division of the upper end of the internal jugular vein
This is third corner of consternation.Access is crucial in a cephalic direction to get above the
disease.upper end of IJV can be located by palpating the transverse process of C2.Two suture are
placed above & below the point of division with transfixing sutures. It is not necessary to remove
the posterior belly of diagastic muscle.
The critical steps in radical neck dissection of the upper neck are
1) Divided the upper end of the sternomastoid in three corner.
2) Retract the posterior belly of the digastrics upwards.
3) Identify & ligate the internal jugular vein.
4) Identify & preserve the hypoglossal nerve.
5) Deal with the retropharyngeal & parapharyngeal nodes.
Dissection of the submandibular triangle(fourth corner)
Anterior belly of digastrics mucle identified. Submandibular gland is then identified & is dissected to
the posterior border of mylohyoid muscle.mylohyoid muscle retracted in a forward direction to
reveal the submandibular duct .submandibualr duct is tied & divided,hypoglossal nerve is kept under
conatant direct vision to avoid any damage.

4.
Once the dissection is completed ,a warm pack is placed into the wound & following Valsalva
manoeuvre ,haemostasis is completed. The wound is irrigated firstly with saline & then sterile water
& any further bleeding points secured.
Closure
Following wound irrigation ,used instruments should be discarded & new gloves can be worn to
close the wound. Two large drains are placed through the posterior flap & securely tied.Drain should
never cross the carotid sheath,
Finally make a check for any chylous leak, this is facilitated by asking the anaesthetist to perform a
valsalva maneurve.
The wound may be left uncovered or a gauze dressing may be applied to the suture line prior to the
release of the drains.it is important at this stage to check for an air leak since drain failure can have
disastrous results.
Complications
General complications; anaesthetic complications postoperative atelectasis with basal collapse as
well as pneumonia & uninary retention ,Deep vein thrombosis.
Local complications;
1)Haemorrhage;
2) wound infection: the four important factors in the development of a wound infection after radical
neck dissection;
-contamination of the surgical field at the time of surgery.
- composite resection , pharyngeal & laryngeal resection.
-postoperative haematoma which becomes infected.
-Flap necrosis & wound break down.
3) carotid artery rupture; Sponteneous rupture of the carotid artery results following necrosis of the
arterial wall due to infection.
Preoperative radiotherapy, post-operative salivery fistula prone to rupture.
4)Chylous fistula; in dissection of left side of neck ,if thoracic duct is seen & damaged it must be
ligated . post operatively ,if the leak is mild (less than 100 ml in a day.) conservative management.
Conservative management involves pressure dressing &parenteral feeding.
If the leak is major >300ml,/day re-explore the wound, identify the leak & oversew it.
5)Pneumothorax; apical pleura may be damaged, air leak at the time if the patient is being ventilated
.

5.
6) Nerve injuries; the accessory nerve , branches of cervical plexus,(lesser occipital, greater
auricular, transverse cutaneous nerve, supraclavicular nerves,) mandibular & cervical branch
of facial nerve, hypoglossal nerve, lingual nerve, vagus, phrenic nerve, brachial plexus.
7) Cerebral oedema ; a certain amount of cerebral oedema occurs after radical neck
dissection, intracranial pressure incranial pressure increase approximately three fold. & five
fold in bilateral radical neck dissection.
A patient with cerebral oedema will have congested face, BP raised, pulse fall,
Management by sitting position, I/V mannitol together with dexamethasone. These patient
often have pharyngeal & laryngeal oedma . Any patient having bilateral neck dissection
(whether simultaneous or staged) should have an elective tracheostomy.
Extended radical neck dissection
This operation consists of removal of all the structures resected in a radical neck dissection along
with one or more additional lymph node groups or nonlymphatic structures or both.
The additional lymph node groups include retropharyngeal & parapharyngeal lymph node, parotid
nodes, or nodes in levels VI Or VII.
Non-lymphatic structures that may be removed include part of the mandible, the parotid gland,
part of the mastoid tip. Prevertebral fascia, & musculature, the digastrics muscle, the hypoglossal
nerve , external carotid artery.
Modified radical neck dissection
This operation consists of removal of all lymph nodes groups (levels I-V) with preservation of one or
more nonlymphatic structures .
Type –I: Removal of all lymph node groups (levels I-V ) with preservation of the spinal accessory
nerve where spinal accessory nerve is not involved.
Type-II: Removal of all lymph nodes group (levels I-V) preservation of the spinal accessory nerve &
internal jugular vein. (particularly second side operations , differentiated thyroid carcinoma).
Type –III: Removal of all lymph nodes groups (levels I-V) with preservation of the spinal accessory
nerve , Internal jugular vein, & sternomastoid muscle. (particularly treatment of N0 neck &
treatment of differentiated thyroid carcinoma.)
Selective neck dissection
A selective neck dissection consists of preservation of one or more lymph nodes groups & all three
nonlymphatic structures.
Selective neck dissection are only indicated in the N0 neck. They should not carried out previous
surgery or radiotherapy.

6.
Selective neck dissection (for the previously untreated No neck)
Type Levels dissected Main indications
supraomohyoid I-III T1-T4 ,N0 neck
Extended
supraomohyoid(anterolateral)
I--IV Skin cancer anterior to the line
of tragus
Lateral II -IV T2-T4, N0 neck
posterolateral II-V(postauricular nodes) Skin cancer posterior to the line
of tragus.
Anterior or centre VI Differentiated thyroid cancer.
Superior mediastinum VII Differentiated & medullary
carcinoma of thyroid. Cervical
oesophageal carcinoma.

7.
Selective neck dissection (for the previously untreated No neck)
Type Levels dissected Main indications
supraomohyoid I-III T1-T4 ,N0 neck
Extended
supraomohyoid(anterolateral)
I--IV Skin cancer anterior to the line
of tragus
Lateral II -IV T2-T4, N0 neck
posterolateral II-V(postauricular nodes) Skin cancer posterior to the line
of tragus.
Anterior or centre VI Differentiated thyroid cancer.
Superior mediastinum VII Differentiated & medullary
carcinoma of thyroid. Cervical
oesophageal carcinoma.