Salivary Gland Operations

Parotidectomy

· Preparation

— Head draped to encompass the ET tube, but expose the corner of the mouth and eye

— Shoulder roll. I prepare the ear and place a small cotton wick inside which is added to the count

— Neck extension & turned away. Suture towel to skin. 30% upward tilt of table

— Bipolar diathermy

— Nerve stimulator

— Patient NOT paralysed

· Incision Lazy-S: preauricular, around pinna, along SCM to about 1cm below angle of mandible

· I apply skin hooks to the anterior skin flap and raise anterior flap at level of parotid fascia just deep to platsyma using diathermy not going beyond the margins of the parotid.

· I elevate skin flaps posteriorly to expose the SCM, mastoid process and cartilage of external auditory canal. I suture the skin flaps to the drapes to maintain exposure using 2/0 Silk.

· Gt auricular nerve overlying the SCM about 3cm below the mastoid process is identified. I divide the branch that enters the parotid gland.

· I divide and ligate the retromandibular vein

· Define nerve

— Dissect along cartilaginous portion of external auditory meatus

   Identify nerve in tympanomastoid fissure by palpating the mastoid process and where it turns in to join the external auditory canal is the vertical surface landmark of the facial nerve.

   I elevate the temporoparotid fascia using an angled haemostat to elevate the posterior portion of the parotid gland away from the mastoid process and uncover the main trunk of the facial nerve

— Stylomastoid artery lies anterior (branch of post auricular a). If it bleeds apply pressure for 5 minutes.

· Dissect along  the branches of the nerve. I retract the superficial lobe using a small Langenbach or allis clamps and pass a haemoatat just superficial to nerve and divide the tissue above the nerve using scissor and bipolar diathermy for haemostasis.

At any bifurcation I follow the more posterior branch of the nerve

— I continue this dissection until each branch has been separated from the parotid tissue.

· I usually transect the glandular tissue gland after clearance of lesion obtained or divide duct anteriorly using 2/0 vicryl if the entire superficial lobe has been removed.

· I take care to separate the duct from the buccal branch closely applied to it.

· I ensure haemostaisis using pressure with a raytech swab, bipolar diathermy and 4/0 vicryl ties.

· I close the skin using subcuticular monocryl over a 10F redivac closed suction drain.

 

How do you remove a benign lesion in the deep lobe of the parotid gland

· First remove the superficial lobe.

· Free the facial nerve from the underlying tissue

· The following vessels must be ligated and divided:

— The retromandibular vein must be separated from the marginal manbidular nerve and divided.

— The superficial temporal artery and vein

— The external carotid artery

— Internal maxillary and transverse facial arteries

How do you remove a malignant lesion that has invaded the facial nerve

· The procedure is radical parotidecomy.

· The entire parotid gland and involved parts of the facial nerve are excised, often combined with MRND.

· The facial nerve should be reconstructed using the auricoltemporal nerve or sural nerve anatomosed with 10/0 Prolene under an operating microscope.

How would you perform facial nerve monitoring

· Peripheral needle electrodes are inserted at four points: Frontalis (temporal branch); orbicularis oculi (zygomatic branch); buccal branch (orbicularis oris); depressor of lower lip (marginal mandibular).

· Electromyographic signal are then recorded producing visual and audible signals when the facial nerve supplying them is stimulated. 

What do you do if you cannot identify the facial nerve

· Use the nerve stimulator

· If the facial nerve cannot be identified at the stylomastoid foramen, the buccal branch can be identified by its relationship to Stenson’s duct.

· This buccal branch can then be followed to the temporfacial division of the nerve.

Complications of parotidectomy

· Freys syndrome (gustatory sweating) 5%

— Damage to auriculotemporal nerve interrupting parasympathetic supply

— Sweating of skin anterior to ear

· Facial nerve palsy

— Transient 5%

— Permanent 1%

· Fistula 1%

· Formication 1%

· Recurrence 1%

 

Submandibular

v Impaction occurs in

— @ orifice: Intraoral removal

— middle 1/3 duct: Intraoral removal

— Hilar region Submandibular galnd excision

Removal of stone

· LA injected over calculus or GA with nasotracheal intubation and pharynx packed off

Keep mouth open with dental prop

Grasp the tip of the tongue with a towel clip and palpate the stone in the floor of the mouth. If the stone is not palpable then do not proceed. If palpable

· Insertion of proximal and distal 3/0 nylon sutures and use these as stays to isolate and control the stone in the duct .

— Retraction

   Prevention of proximal migration of calculus

   Pass a lacrimal probe into the orifice of the duct and incise onto the stone preserving the last 0.5cm of the duct. Lift the stone out. If you cannot lift the stone out without compromising the integrity of the duct orifice sew the duct lining to the floor of the mouth using 4/0 vicryl rapide.

· Wound left open

 

Excision of submandibular gland for stone disease

· Preparation and position as for parotidecomy

— Head draped to encompass the ET tube, but expose the corner of the mouth and eye

— Shoulder roll. I prepare the ear and place a small cotton wick inside which is added to the count

— Neck extension & turned away

— Bipolar diathermy

— Patient NOT paralysed

· Incision 3-4cm below ramus of mandible over gland

· Dissect directly down onto gland incising the skin, fat, platsyma from anterior border of SCM to 3cm from midline

NO flaps

· Define inferior border of the gland

   Identify and divide facial artery / and retromandibular vein

   Keeping very close to the gland capsule reduces the chance of injury to the marginal mandibular nerve.

· Dissect off digastric tendon and anterior belly

· Dissect off mylohyoid anteriorly

· Dissect superior border

— Identify and divide posterior and anterior facial vein and facial artery

· Dissect deep portion (posterior) off stylohyoid

v Stylohyoid splits around posterior belly digastric

— Identify and divide facial artery as comes round stylohyoid

· Apply tissue forceps to the gland as it passes posterior to the border of mylohyoid.

· Retract mylohyoid and separate the deep portion of the gland from muscle by blunt dissection

· Dissect the deep portion of the deep lobe from the hyoglossus muscle gently using blunt dissection.

· At this point identify lingual nerve superior to duct

— Divide fibres from submandibular ganglion to gland

· Identify & preserve hypoglossal nerve inferior (deep) to duct

· I free the duct as far anteriorly as possible and ligate and divide it using 2/0 Vicyrl taking care not to damage the nerves.

· I check haemostasis. I insert a 10F redivac drain into the wound bringing the tube out below the midline of the incision.

· I close the platsyma with 4/0 vicryl and 4/0 Monocyryl subcuticular to skin.