ENT Head and Neck

• Cartilage formed by chondrofication of the first arch mesenchyme
• It makes mandible

• Cartilage formed by chondrofication of the 2nd arch mesenchyme
• It makes astyloid process, lesser cornu and upper body of hyoid,

• Superficial : thin subcutaneous layer invests platisma and facial expression muscles
• Deep:
• Superficial or investing layer: invests SCM, trapezius, omohyoid, strap muscles, parotid, it makes Carotid sheath.
• Middle: encircles trachea, thyroid, oesophagus.
• Deep: encloses post vertebral muscles, forms prevertebral layer, and floor of posterior triangle. (has two layers: alar, and deep layer)

• Submental
• submandibular
• peritonsilar
• parapharyngeal
• retropharyngeal
• pretracheal (containe DELPHIAN node)
• prevertebral (extends down to T3)

• It is shaped like an inverted pyramid.the top of which is the base of skull and the inferior part isthe greater cornu of the hyoid bone. It is bounded medially by the superior constrictor and laterally by the pterygoid muscles, the mandible and deep lobe of the parotid gland. The parapharyngeal space is divided by the styloid process and its attachments into the prestyloid and poststyloid spaces. The prestyloid space contains ectopic salivary tissue. while the poststyloid contains carotid arteries, internal jugular vein, cranial nerves 9-12, cervical sympathetic chain and lymph nodes.
• The parapharyngeal space contains a fat pad, which is located centrally. The radiological displacement pattern of this fat pad is useful for diagnosing lesions in this area. Prestyloid and lateral lesions will displace the fat posteromedially,while poststyloid lesions will displace this fat anteriorly.

IJV

• submental: (Level Ia) from anterior floor of moth
• submandibular: (Level Ib) floor of mouth, tongue, buccal cavity
• jugular chain:
• jugulodigastric: (Level II) posterior faucial region, palatine tonsil
• junctional: lymphatic anastomosis of submandibular, retropharyngeal, and jugular nodes
• Middle jugular: (Level III) from larynx, midhypopharynx, upper thyroid.
• Lower jugular: (Level IV) important confluence between mediastinal, axillary and neck nodes.
• Posterior:
• along CN XI: (Level Va) from nasopharynx
• along thyrocervical: (Level Vb) from anterior neck nodes
• Level VI: paratracheal, perithyroidal and delphian nodes
• Level VII: Superior mediastinal tissues.

The thoracic lymphatic duct joins the vein at the intersection with the subclavian vein in Chassaignac'striangle, which is formed by the longus colli, scalenus anterior with the subclavian artery at the base, the apex isformed by the tubercle of the sixth thoracic vertebra (Chassaignac's tubercle).

This nerve runs inferior to the angle of the mandible, it dips down into the neck and runs superficial to the submandibular triangle. The nerve runs just deep to the platysma and is superficial to the deep fascia. It runs inferior to the greater cornu of the hyoid bone, which is the inferior landmark of its course. It curves upwards and crosses the mandible for a second time close to the facial artery and vein. It lies deep to the depressor anguli oris,which it supplies. It also supplies risorius and the muscles of the lower lip.

• auricular branch (Arnold)
• carotid body branches
• pharyngeal branches
• superior laryngeal branches
• cardiac branches
• recurrent laryngeal branches.

The accessory nerve exits the muscle at the junction of the upper and middle thirds of the posterior border, a point known as Erb's point.

all the intrinsic muscles of the tongue and all the external muscles, except the palatoglossus (which is innervated by vagus).

• Interruption of cervical sympathetic trunk:
• ptosis
• meiosis
• anhydrosis
• itchy scalp
• blocked nose

Thyroglossal duct cyst

• reactive LMP
• in children: dermoid cyst or rhabdomyosarcoma
• in young adults: lymphoma, TB, nerve sheath tumours
• over 35: cervical mets

• hystiocytic necrotizing lymphadenitis, without granular cell infiltration, affecting young women.
• Malaise, mild fever, painless posterior triangle cervical LMP.
• benign, resolves in months

Stensen, 5cm

• 1. Type 1 (25 percent). There are no anastamotic links between the main branches,
• 2. Type 2 (14 percent). The buccal branch subdivides and fuses with the zygomatic branch.
• 3. Type 3 (44 percent). There are major anastamotic links from the buccal branch to other major branches.
• 4. Type 4 (14 percent). There is complex branching and anastamotic links between the two divisions.
• 5. Type 5 (3 percent). The facial nerve trunk divides before leaving the stylomastoid foramen.

• Drugs: Hyoscine, Tricyclic antidepressions, Monoamine oxydase inhibitors, hyoscine, phenothiazines, antiparkinson, antihistamine.
• ageing, more in females
• Depression
• RT
• autoimmune
• Viral: HIV, HSV 6, Hep C
• GVHD
• sarcoidosis
• Iron overstorage
• amyloidosis

• mumps (paramyxovirus, in young, can cause orchitis, meningitis, encephalitis, deafness)
• acute suppurative sialadenitis (pain, fever?, purulant D, dysgeusia, LMP, related to xerostomia and RT)
• Juvenile recurrent parotitis (3-6 years, local pain, sialectasis)
• Sialolithiasis (more in submandibular, female, pain/swelling in eating, x-ray good Ix, but 30% of stones are radiolucent)
• Sjogren syndrome
• drug induced xerostomia (antihistamines, TCA, antiemetics, antiparkinson)
• HIV (mimics Sjogren's symptoms, or gland enlargment)
• Sialosis (bilat, late life, related to DM, malnutrition, alcohol, menopause)

• 2nd most common autoimmune disease of connective tissue
• cause: unknown
• pathology: lymphocytic infliltration of glands
• types:
• primary: (xerostomia, xerophtalmia)
• Secondary: Primary + other connective tissue diorder (RA)
• symptoms: dysphagia, dysgeusia, dysarthria, eye discomfort, oral candidiasis, dental caries, median glossitis, parotid swelling.
• risk of MALTtumour, lymphoma
• Ix: Schirmer, rose-bengal, HPT, autoantibody to RA(SSA), LO(SSB)
• Tx: Pilocarpine, Bethanecol, Pyridostigmine, bromhexine, steroid, HCQ,electrostimulation, salivary substitude, chewing gum

• Disease: multiple lymphoepithelial lesions of the lacrimal and salivary glands. (variant of Sjogren)
• Miculicz syndrome simply reflects other disorders characterized by lacrimal and salivary gland disease that mimics Sjogren syndrome, but is associated with disorders such as sarcoidosis, lymphoma and other similar systemic disorders.

mucocoeles

1, Medial pterygoid plate; 2, tensor palati; 3, levator palati; 4,pterygomandibular raphe; 5, palatoglossus; 6, tonsillar branch offacial artery; 7, glossopharyngeal nerve; 8, stylohyoid ligament;9, stylopharyngeus; 10, epiglottis; 11, phayngotympanic tube;12, pharyngobasilar fascia; 13, salpingopharyngeus; 14, superiorconstrictor; 15, palatopharyngeal sphincter; 16,palatopharyngeus-anterior bundle; 17, palatopharyngeusposteriorbundle; 18, middle constrictor; 19, inferior constrictor.

• All the muscles of the soft palate, except the tensor palati,are supplied by the pharyngeal plexus (cranial root ofaccessory and vagus) with an additional supply from the facial nerve (greater petrosal nerve). The tensor palati issupplied by the trigeminal nerve through the nerve to the medial pterygoid muscle.
• Sensation to the palate is provided by the maxillary division of the trigeminal nerve, through its greater and lesser palatine branches, and the pharyngeal branches of the glossopharyngeal nerve.
• Sympathetic fibres reach the palate on the blood vessels supplying it and are derivedfrom the superior cervical ganglion.

The pharyngeal wall consists of four layers which,from the inside out, are the mucous membrane lining,the pharyngobasilar fascia, the muscular layer and the buccopharyngeal fascia.

• The cartilaginous portion of the Eustachian tube and the tensor and levator palati pass through the pharyngobasilar fascia. The palatine branch of the ascending pharyngeal artery curls over the upper edge of thesuperior constrictor.
• The stylopharyngeus enters the pharynx between the middle and superior constrictors, accompanied by the glossopharyngeal nerve which supplies it before passing forwards tothe tongue.
• The internal laryngeal nerve and superior laryngeal nerve pierce the thyrohyoid membrane between the middle and inferior constrictors.
• The recurrent laryngeal nerve and inferior laryngeal artery pass between the cricopharyngeal part of the inferior constrictor and the oesophagus.

The pharyngeal plexus is formed by the pharyngeal branches of the glossopharyngeal and vagus nerves with sympathetic fibres from the superior cervical ganglion. Many of the vagal fibres come from the cranial root of the accessory, which joins the vagus at its superior ganglion.The pharyngeal branches of the vagus supply all the muscles of the pharynx via the pharyngeal plexus, except the stylopharyngeus which is supplied by the glossopharyngeal nerve.

• sore throats are due to tonsillitis
• there are five or more episodes of sore throat peryear
• there are symptoms for at least a year
• the episodes of sore throat are disabling and preventnormal functioning.
• following resolution of a second Peri Tonsilar Abscess
• Asymmetrical adult tonsil with normal mucosa in the absence of cervical adenopathy has an approximately7 percent risk of malignancy'" primarily B-celllymphoma.
• Asymmetrical adult tonsil with mucosal abnormality and or cervical adenopathy has a very high risk of malignancy with asymmetry being the strongest predictor.
• As an oncological procedure for Ca tonsil
• OSA in children
• In adults with gross tonsil hypertrophy and OSA, or as part of (UPPP) or laser-assisted uvulopalatoplasty.
• Severe haemorrhagic tonsillitis.
• Severe infectious mononucleosis with upper airwayobstruction.
• Large symptomatic tonsoliths (tonsillarconcretions)
• As long-term management of 1gA nephropathy.

• Hand, foot, and mouth disease is a common viral illness that usually affects infants and children younger than 5 years old. However, it can sometimes occur in adults. Symptoms of hand, foot, and mouth disease include fever, mouth sores, and a skin rash.
• Enterovirus 71
• coxackie viruses
• ...

• 50% asymptomatic
• fever
• sepsis
• headache
• severe odynophagia

Zenker diverticulum AKA pharyngeal pouch

• conservative: for small ones
• endoscopic surgery (Dohlman's procedure)
• diathermy, laser, stapling
• cricopharyngeal myotomy alone
• excision +- cricopharyngeal myotomy
• Inversion + cricopharyngeal myotomy
• external approach surgery

Aspiration is defined as laryngeal penetration of secretions,such as saliva, ingested solids and liquids, or refluxed or regurgitated gastric contents below the level of the truevocal cords.

• Neuromascular: CVA,MS, Parkinson, bain injury, Guillain barre, MG, MD,
• gastrointestinal disease: ZD, GERD, achalasia, post RT
• Mechanical: NGT, ETT, tracheostomy
• other: severe debilitation

• CXR
• contrast swallow
• Rigid/flexible endoscopy
• Barium videofluroscopy swallowing study (gold standard)

• conservative: treat pneumonia, NGT, Pharyngostomy, gastrostomy, jejunostomy, tracheostomy with inflated low-pressure cuff
• surgical: VC medialization, cricopharyngeal myotomy, narrow field laryngectomy, epiglottopexy+tracheostomy, vertical laryngoplasty, subperichondrial cricoidectomy, partial submucosal cricoidectomy, glottic closure, tracheo-oesophageal diversion, laryngotracheal separation. total laryngectomy.

Posterior to the tubal elevation is the lateral pharyngeal recess (fossa of Rosenmliller) which is formedby the projection of the tubal cartilage into the pharynx.

• There are three types of epithelium in the nasopharynx: columnar pseudostratified ciliated 'respiratory-type' epithelium with goblet cells and seromucinous glands is found in the region of the choanae,on the roof and upper portion of the posterior wall.
• 
• non keratinizing stratified squamous epithelium is found on the lower half of the lateral and posterior walls and is continuous with that in the oropharynx.
• 
• an intermediate epithelium of columnar cells with short microvilli instead of cilia lies between these two zones.

Lymphoid tissue found on the rim of the tubal elevation, the tubal tonsil.

• mucosa: repiratory, non-keratinizing squamous and intermediate type
• submucosa: a thick strong layer
• muscular: inner longitudinal: stylopharyngeus, salpingopharyngeus, palatopharyngeus, and outer cicunferential 3 constrictors.
• adventitia: buccopharyngeal fascia

The ectodermal upgrowth in the form of a pouch, known as Rathke's pouch, a depression in nasopharynx, forms the adenohypophysis (glandular portion of the pituitary) comprising the pars anterior, the pars intermedia and the pars tuberalis.

• Rathke's pouch remnants and pharyngeal hypophysis
• Nasopharyngeal glioma (rare)
• hairy polyp or nasopharyngeal dermoid
• congenital deficit in nasopharyngeal form:
• Down, Crouzone,Apert, Treacher Collins syndrome
• Toruous vessels in the nasopharynx (ICA)
• Aquired Conditions:
• Adenoids
• Thornwald's cyst (Cyst of bursa pharyngeal embryonalis)
• Retention cysts
• Benign neoplasms:
• JNA
• Schwannomas