ENT Flashcards
Borders of the anterior triangle in the neck
Superiorly – inferior border of the mandible (jawbone).
Laterally – anterior border of the sternocleidomastoid.
Medially – sagittal line down the midline of the neck.
The contents and boundaries of the anterior triangle in the neck
Carotid triangle
- Sup – post belly digastric; Lat - med SCM; infer - sup belly omohyoid
- common carotid artery (bifurcates; + carotid sinus - BaroR), internal jugular vein, hypoglossal and vagus nerves.
Submental triangle
- Inf – hyoid bone; Med– midline of neck; La - ant belly digastric
- submental lymph nodes
Submandibular Triangle
- Sup – body of mandible; Ant – ant belly digastric;
Post – post belly digastric
- submandibular gland (salivary), and lymph nodes.
Muscular Triangle
- Sup– hyoid bone; Med – midline of the neck; Supero-lat – sup belly omohyoid; Infero-lat – inf portion SCM
- Infrahyoid muscles, the pharynx, and the thyroid, parathyroid glands.
Borders of the posterior triangle and its contents
Ant – post SCM; Post– ant trapezius; Inf– middle 1/3 clavicle.
Split by omohyoid into - occipital triangle (larger + sup) and subclavian triangle (contains distal subclavian A)
- Muscles –> omohyoid;
- external jugular vein –> empties into the subclavian vein
- distal part of the subclavian artery
- accessory nerve (CN XI) and cervical plexus (+phrenic N)
Where is the thyroid gland located and its blood supply
- anterior neck (post to muscles)
- C5 and T1 vertebrae; inferior to thyroid cartilage
- divided into 2 lobes connected by an isthmus
- butterfly shape.
- superior and inferior thyroid A; drainage via super, middle and infer thyroid veins –> int jug vein
Pathophysiology and presentation of thryoglossal cysts
As the thyroid gland descends during development, it moves through a duct called the thyroglossal duct. This duct normally fuses and regresses in the adult.
However, in 50% of individuals, the distal portion of the duct continues as a pyramidal lobe – effectively an extra piece of thyroid tissue. (No clinical consequences).
Other portions of the duct may persist as thyroglossal cysts. These present with a mass in the midline of neck, and can be excised surgically.
Sx - non-tender fluctuant swelling in the midline. Move up when pt extends tongue.
Where are the parathyroid glands located and how many are there
Posterior aspect of the lateral lobes of the thyroid gland. They are flattened and oval in shape, situated external to the gland itself, but within its sheath.
Most people have 4 - 2 from sup parathyroid (from 4th pharyngeal pouch); 2 from inf parathyroid ( from 3rd pharyngeal pouch)
- supplied by inf thyroid A
What are the paranasal sinuses and where do they empty
Extensions of the respiratory part of the nasal cavity - air filled space lined by ciliated pseudostratified resp epi.
4 pairs:
named according to the bone in which they are located; - - maxillary - middle meatus
- frontal- middle meatus
- sphenoid - roof or nasal cavity
- ethmoid - post= sup meatus; middle/ant = middle meatus
Where is epistaxis most likely to develop from
Kiesselbach/ Littles area.
kiesselbachs plexus:
- -> anterior ethmoidal artery
- -> sphenopalatine artery (max A branch)
- -> greater palatine artery (max A branch)
- -> superior labial artery (branch facial A)
Types of audiometry
Quantify loss and determine its nature.
Pure tone audiometry (PTA)
- tones at different frequencies and strengths
-Pt. indicates when sound appears and disappears
-Mastoid vibrator –>bone conduction threshold.
- Threshold at different frequencies are plotted to
give an audiogram.
> age-related hearing loss and sensoineural - lose high freq
> otosclerosis + menieres- lose all freq
Tympanometry
- Measures stiffness of ear drum
- Evaluates middle ear function
- Flat tympanogram: mid ear fluid or perforation
- Shifted tympanogram: +/- mid ear pressure
Evoked response audiometry
- Auditory stimulus –> measurement of elicited brain response by surface electrode.
- Used for neonatal screening (if otoacoustic emission testing negative)
What is the normal range of hearing and the grades of hearing loss
- 0-20dB
mild - 20-40
mod - 41-70
severe - 71-95
profound - >95
Causes of hearing loss
Conductive - problem with transmission of soundwaves from external ear through middle ear --> WIDENING Wax/FB Infection (otitis media +/- effusion) Drum perf (trauma/infection) Extra - otosclerosis Neoplasia / no vent of middle ear Injury (barotrauma) Granulomatous (wegeners/sarcoid)
Sensoineural - problem in cochlear, cochlear N or brainstem –> DIVINITY
Development (alport/TORCH/perinatal anoxia) and degen (presby)
Infection - VZV, measles, mumps, influenza, meningitis, HZV
Vasc - int aud A ischaemia (+vertigo), stroke
Inflam (vasculitis/sarcoid)
Neoplasia (CPA tumour, acoustic neuroma)
Injury (noise, head trauma)/ MS/ low b12
Toxins (gentamycin, furosemide, aspirin, vancomycin)
lYmph (menieres, perilymphatic fistula (rupture round window))
Presentation, causes and differential of otitis externa
Presentation
Purulent discharge; Itch/ ear fullness Pain and tragal tenderness; localised red +swelling; warm +/- blood; conductive hearing loss
- narrowing of the canal + accumulation of debris, leads to further entrapment of pathogens and propagating the infective process.
Discharge - White-yellow – bacterial; Thick white grey with visible hyphae or spores – fungal;
Causes –> Any interruption in wax formation
- repeated water exposure
- trauma to the canal (e.g. cotton buds)
- blockage (e.g. debris)
Organisms –> Mainly pseudomonas; S. Epidermidis; S.aureus
Differential - Clear grey – otitis media +/- blood - perf. Relief of pain.
Mx and complications of otitis media
- prevention - debris removed by microsuction; avoid swimming; mx eczema
- aural toileting
- topical antibiotics (depending on local protocol)
- simple analgesia
- Steroid drops (if canal inflam)
Complication - Malignant otitis externa –> extension –> skull osteomyelitis
-90% of pts. are diabetic (or other immune compromise)
Presentation
- Severe otalgia which is worse @ night +/- headache
- Copious otorrhoea
- Granulation tissue in the canal
- can involve CN VII
Ix - urgent CT scan
Rx - Surgical debridement; IV abx
What is Bullous Myringitis
Painful haemorrhagic blisters on deep meatal skin and TM.
Assoc. ̄c influenza infection
presentation of TMJ dysfunction
- Symptoms Earache (referred pain from auriculotemporal N.) Facial pain Joint clicking/popping Teeth-grinding (bruxism) Stress (assoc. ̄c depression)
Signs
Joint tenderness exacerbated by lateral movements of an open jaw.
Investigation –> MRI
Management –> NSAIDs; Stabilising orthodontic occlusal prostheses
Presentation and mx of Ramsay-Hunt Syndrome
Herpes Zoster oticus - unilateral facial palsy caused by reactivation of VZV from the geniculate nucleus on CNVII
Clinical Features
- moderate to severe ear pain
- facial palsy within few days (more severe than bells) + ipsilateral vertigo, hyperacusis, and tinnitus.
O/E - Vesicles will be visible during this latter period, covering the concha, anterior ⅔ tongue, +/- soft palate
Mx - prednisolone and acyclovir ASAP
~ 75% of cases will resolve
Complications - chronic tinnitus + vestibular dysfunction.
Presentation, RF and common organisms causing acute otitis media
Presentation Usually children post viral URTI Rapid onset ear pain, tugging @ ear. Irritability, anorexia, vomiting Purulent discharge if drum perforates \+/- malaise, fever, and coryzal symptoms o/e Bulging, red TM; Fever - make sure test function of facial N
Common organisms - RSV, H. influenzae, S. pneumoniae, Moraxella catarrhalis, and S.pyogenes,
RF - Age (peak age 6-24 months); Parenteral / passive smoking; Previous URTI; Presence of enlarged adenoids; Bottle feeding or dummy use (breast feeding is protective); GORD and BMI (in adults)
Ix, Mx and complications of acute otitis media
Ix - cultures if pyrexial, swab discharge if present
Mx -majority resolve < 24 hours, nearly all within 3 days.
- simple analgesics
- if systemically unwell - Amoxicillin
Complications
Mastoiditits; Meningitis; Facial nerve paresis; Intracranial abscess; Sigmoid sinus thrombosis; Chronic Otitis Media; OME; perforation TM; sepsis; IE; septic arthritis
Presentation, ix and rx of otitis media with effusion
Presentation Inattention at school Poor speech development Hearing impairment/ aural fullness Hx previous acute otitis media o/e Retracted dull TM; Fluid level Ix Audiometry: flat tympanogram Rx Usually resolves spontaneously, Consider grommets if persistent hearing loss SE: infections and tympanosclerosis Same complications as acute otitis media
Presentation of chronic suppurative otitis media
Painless discharge and hearing loss (conductive)
- chronic discharging ear >6 weeks
o/e –> TM perforation +/- discharge
Rx
- Aural toilet; Abx / Steroid ear drops
+/- tympanoplasty if ear drum doesn’t repair itself
Complications
- Cholesteatoma; labyrinths
presentation and mx of mastoiditis
Middle-ear inflam - destruction of mastoid air cells and abscess formation.
Sx - Fever; Mastoid tenderness/ swelling; Protruding auricle
Rx- IV Abx; CT head if no improvement >24 hr
? Myringotomy ± mastoidectomy
Risk meningitis
presentation and mx of Cholesteatoma
Locally destructive expansion of stratified squamous epithelium within the middle ear.
- congenital/ acquired secondary to chronic OM
Presentation
Foul smelling white discharge
Headache, pain
CN Involvement –> Vertigo; Deafness (conductive) ; Facial paralysis
o/e –> Appears pearly white - surrounding inflammation
Complications
Deafness (ossicle destruction); Meningitis; Cerebral abscess
Mx
Surgery to remove (open/closed)
Define and name causes of tinnitus
Sensation of sound w/o external sound stimulation Causes - Specific Meniere’s (vertigo+deafness)) Acoustic neuroma (unilateral +vertigo+ deafness) Otosclerosis (?FH) Noise-induced Head injury Hearing loss: e.g. presbyacusis
- General
high BP
anaemia
- Drugs Aspirin Aminoglycosides Loop diuretics EtOH
Mx of tinnitus
Treat any underlying causes
Psych support: tinnitus retraining therapy
Hypnotics @ night may help
Presentation and mx of otosclerosis
AD condition characterised by fixation of stapes at the oval window. F>M=2:1
Presentation
Begins in early adult life
Bilateral conductive deafness + tinnitus
HL improved in noisy places: Willis’ paracousis
Worsened by pregnancy/ menstruation/ menopause
difficulty hearing low, deep sounds and whispers
?dizziness
Ix - PTA shows dip (Caharts notch) @ 2kHz
Rx - Hearing aid or stapes implant
Causes of vertigo
IMBALANCE
Infection/injury e.g. labyrinthitis/ head injury
Meniere’s
BPV
Aminoglycosides/Fudrosemide/ metronidazole
Lypmph - peri-fistula
Arterial - migraine; TIA; stroke
Nerve - acoustic neuroma /vestibular schwannoma
Central lesion - demyelination (MS), tumour, infarct
Epilepsy - complex partial
