Head Flashcards
Name the type of contrast agent used in MRI and why you would use it?
Gadolinium
Used to help highlight more vascular tissue E.g. cancer or inflamed tissue
What would you consent a patient for having Parotid surgery (min 4)
Facial nerve weakness (permanent 1%, temporary up to 30%)
Sensory loss around ear (greater auricular nerve)
Silocele
Seroma
Bleeding / haematoma formation
Frey’s syndrome (gustatory sweating)
Recurrence
Infection
Pathophysiology of Frey’s syndrome
Gustatory sweating due to damage to auriculotemporal branch of V3.
It carries parasympathetic to parotid gland and sympathetic to scalp (sweating). Parasympathetic fibres can become sympathetic due to inappropriate regeneration of nerve
Treatment of frey’s syndrome
Gold standard: Botox injections
Aluminium based deodorant
Topical glycopyrrolate
Neuronectomy (Jacobson’s nerve section in the middle ear)
Pleomorphic adenoma treatment and information to patient
Risk of 1% per year of malignant transformation
M=F
Peak incidence 5th decade
They can recur
Treatment
- Conservative (watchful waiting, ultrasound and examination follow up)
- Surgery
What is the 80% rule re. Parotids?
- 80% of parotid tumours are benign
- 80% of parotid tumours are pleomorphic adenomas
- 80% of salivary gland pleomorphic adenomas occur in parotid
- 80% of parotid pleomorphic adenomas occur in the superficial lobe
- 80% of untreated pleomorphic adenomas remain benign
Incisions for Parotidectomy
Modified Blair incision
Modified Facelift incision
How can you locate the affected regions in Frey’s syndrome?
Iodine starch test may be used
Pait pt with iodine, then starch, then ask them to eat something and look for the areas that sweat and inject with botox
Causes of parotid enlargment
Parotitis
Infective: Mumps HIV TB
Autoimmune: Sjogren’s syndrome
Granulomatous: Sarcoid, TB
Benign tumours e.g. pleomorphic
Malignant tumours e.g. acinic cell, adenoid cyctic carcioma
Drugs - TOPIC: Thiouracil, Oral contraceptive pill, Phenylbutazone, Isoprenaline and Co-proxamol
Pseudo hypertrophy of masseter muscles
Investigations for parotid mass
USS
USS+ FNA
CT/MRI if indicated
Malignant salivary neoplasms
Adenoid cystic carcinoma
Mucoepidermoid carcinoma
Accinic cell carcinoma
Metastatic lesions (eg malingnant melanoma)
Lymphoma
What vessel do you need to be careful of during Parotid sugery when dissecting the facial nerve?
Stylomastoid artery (branch of posterior auricular artery)
which exits the stylomastoid foramen with the facial nerve.
4 ways to find facial nerve during parotid surgery
Tragal Pointer - VII is 1cm deep and inferior
Tympanomastoid suture (most consistent) - VII approx 2mm inferior to suture line
Posterior belly of the digastric - approx 1 cm superior and parallel to the upper border of the digastric muscle near its insertion at the mastoid tip.
Retrograde dissection of peripheral branch
Warthin’s tumour epidemiology and it’s other name
Papillary cystadenoma lymphomatosum
Male : Female = 7:1
Peak incidence 7th decade
10% bilateral (rarely synchronous)
Rarely recur
Sialolithiasis
What is it and demographics
- most common site
- male / female
- age
Most commonly submandibular (Wharton’s) duct
Rarely sublingual, sometimes the Parotid (Stenson’s) duct
Male > Female
Affects 0.45% population
Generally age 30-60
