EN1.1-2 | ENT Foundations — Glossary

An autoimmune systemic illness occurring 2–4 weeks after untreated GABHS tonsillitis/pharyngitis; caused by molecular mimicry between streptococcal M-protein epitopes and cardiac valve proteins; manifests as migratory polyarthritis, carditis (mitral > aortic valve), Sydenham's chorea, erythema marginatum, subcutaneous nodules (Jones criteria); leads to rheumatic heart disease.

Pathological enlargement of the pharyngeal tonsil (adenoid) in the nasopharynx; causes: Eustachian tube obstruction → OME and hearing loss; nasopharyngeal obstruction → mouth breathing, snoring, and obstructive sleep apnoea; adenoidfacies from chronic mouth breathing; treated with adenoidectomy ± grommets.

A single, unilateral benign polyp arising from the maxillary antrum, extending through the middle meatus and through the posterior choana into the nasopharynx; occurs in children and young adults; not strongly associated with allergy; treated by endoscopic polypectomy including removal of the antral base; does NOT recur when completely excised.

The 'unsafe'/squamosal type of COM: attic or marginal perforation of the TM, foul-smelling discharge, cholesteatoma present, bone erosion (ossicles, facial nerve canal, tegmen, sigmoid sinus); carries risk of facial palsy, meningitis, brain abscess, labyrinthitis; ALWAYS requires surgical treatment (mastoidectomy).

A dip in bone conduction thresholds at 2000 Hz on audiometry in stapedial otosclerosis; a mechanical artefact of stapes fixation (not true cochlear damage); typically reverses after successful stapedectomy; its presence in a patient with conductive hearing loss and a normal-looking TM is highly suggestive of otosclerosis.

A standardised anatomical classification of cervical lymph nodes used in head and neck oncology: levels I–VI in the neck, level VII in the superior mediastinum; each level drains specific head/neck primary sites, guiding neck dissection planning and staging.

An accumulation of desquamating keratinising squamous epithelium in a retraction pocket (atticoantral CSOM) or a congenital rest (congenital type) within the middle ear; releases collagenolytic enzymes (matrix metalloproteinases) and inflammatory cytokines that erode surrounding bone, driving the destructive complications of atticoantral CSOM.

A chronic inflammatory condition of the middle ear cleft with a non-intact tympanic membrane of at least 3 months' duration; divided into tubotympanic (mucosal/'safe') and atticoantral (squamosal/'unsafe') types based on pathological mechanism, site, and complication risk.

The fibrous membrane connecting the inferior margin of the thyroid cartilage to the superior margin of the cricoid ring; the site for emergency cricothyroidotomy (NOT elective tracheostomy); easily palpable in the midline of the neck as a slight depression below the laryngeal prominence.

Bilateral, multiple, pale, glistening, oedematous polyps arising from the ethmoidal sinus mucosa in adults; driven by chronic eosinophilic inflammation (allergic rhinitis, asthma, Samter's triad); treated with topical corticosteroids ± FESS; characteristically recur after surgery due to the persistent underlying eosinophilic mucosal process.

A channel connecting the middle ear to the nasopharynx; equalises air pressure between the middle ear and the atmosphere; opens during swallowing and yawning; shorter and more horizontal in children, predisposing to otitis media.

Endoscopic surgery to open the sinus ostia and remove obstructing disease (polyps, thickened mucosa) under nasal endoscope visualisation, restoring mucociliary drainage; used for nasal polyposis unresponsive to topical steroids, chronic sinusitis, or antrochoanal polyp; complications include orbital (damage to lamina papyracea) and skull base/CSF leak (damage to cribriform plate).

The region of the larynx consisting of the true vocal folds (cords) and the anterior and posterior commissures; the site of voice production; has minimal lymphatics, so glottic carcinoma typically presents early with hoarseness before nodal spread.

The dominant bacterial cause of acute tonsillitis (approximately 30% of cases); treated with penicillin to prevent immunological complications (acute rheumatic fever — mediated by molecular mimicry with cardiac proteins; post-streptococcal glomerulonephritis). Amoxicillin is avoided if EBV mononucleosis is suspected — causes drug rash in 90% of EBV-positive patients.

A vascular anastomosis on the anterior nasal septum at the vestibule, where five arteries converge: anterior and posterior ethmoidal, sphenopalatine, greater palatine, and superior labial arteries; the commonest site of epistaxis, especially in children.

Surgical removal of the mastoid air cells, attic, and the diseased contents (cholesteatoma, granulation tissue, infected bone) of the middle ear cleft; the definitive treatment for atticoantral CSOM with cholesteatoma; variants: canal wall up (posterior EAC wall preserved) and canal wall down (posterior EAC wall removed — wider access, lower recurrence, but lifelong cavity maintenance required).

The mechanism by which respiratory mucosa continuously moves the mucus blanket posteriorly and inferiorly toward the pharynx using coordinated ciliary beating; the primary defence of the nasal cavity and paranasal sinuses against inhaled particles and pathogens; impaired in primary ciliary dyskinesia and cystic fibrosis.

Surgical repair of a tympanic membrane perforation using a graft (typically temporalis fascia or tragal perichondrium) placed under or over the perforation; performed when the ear has been dry for ≥3 months; restores hearing and prevents recurrent middle ear infection in tubotympanic CSOM.

The auditory sensory organ on the basilar membrane within the cochlear duct (scala media); contains inner and outer hair cells whose stereocilia are deflected by basilar membrane movement, converting mechanical vibration to electrical nerve signals via CN VIII.

The three smallest bones in the body — malleus (attached to the TM), incus (interposed), and stapes (footplate in the oval window) — forming the mechanical chain transmitting sound from the tympanic membrane to the inner ear with amplification (~27 dB).

The anatomical region in the middle meatus through which the maxillary, anterior ethmoid, and frontal sinuses drain; blockage of the OMC (by mucosal oedema, polyp, or anatomical variation) is the primary mechanism of recurrent sinusitis.

Accumulation of non-purulent viscous fluid in the middle ear behind an intact TM, most commonly in children; caused by Eustachian tube dysfunction (often from adenoid hypertrophy obstructing the tube orifice); produces mild to moderate conductive hearing loss; on tympanometry: Type B (flat) curve.

A localised disease of the otic capsule bone in which abnormal spongy vascular bone replaces the normal dense enchondral bone; most commonly at the fissula ante fenestram anterior to the oval window, causing stapes fixation and progressive bilateral conductive hearing loss; autosomal dominant, Caucasians, female predominance, worsens in pregnancy.

Evidence-based indications for tonsillectomy in recurrent tonsillitis: ≥7 documented episodes in 1 year, or ≥5 per year for 2 consecutive years, or ≥3 per year for 3 consecutive years; each episode meeting at least one of: temperature >38.3°C, cervical lymphadenopathy, tonsillar exudate, or positive GABHS culture.

A fascial space lateral to the pharynx and medial to the parotid gland, containing the internal carotid artery, internal jugular vein, and cranial nerves IX–XII in its retrostyloid compartment; infection here can arise from peritonsillar abscess, parotitis, or dental disease.

The upper portion of the tympanic membrane between the anterior and posterior malleal folds; lacks the middle fibrous layer, making it structurally weaker; the site of primary acquired cholesteatoma (attic retraction pocket).

A collection of pus in the peritonsillar space (between the tonsillar capsule and the superior constrictor muscle), complicating bacterial tonsillitis; presents with severe unilateral throat pain, trismus, 'hot potato' voice, drooling, and contralateral uvular deviation; requires incision and drainage plus interval tonsillectomy.

The external ear, a cartilaginous framework covered by skin; its named landmarks (helix, antihelix, tragus, antitragus, lobule, concha) are used to localise lesions; its shape functions to collect and directionally focus sound.

Branch of CN X supplying motor fibres to all intrinsic laryngeal muscles EXCEPT the cricothyroid; left RLN has a longer intrathoracic course (loops under the aortic arch), making it more vulnerable to mediastinal pathology and thyroid surgery; right RLN loops under the right subclavian artery.

Earache arising from pathology OUTSIDE the ear, transmitted via shared nerve supply: CN V3 (dental/temporomandibular), CN IX (tonsil, pharynx), CN X (larynx, hypopharynx, oesophagus), CN VII (EAC/concha), C2/C3 (posterior scalp/neck); in adult smokers, referred otalgia is a red flag for head/neck malignancy.

The triad of aspirin/NSAID sensitivity + asthma + nasal polyposis; caused by COX-1 inhibition diverting arachidonic acid metabolism to leukotriene overproduction, producing bronchospasm and nasal congestion; NSAIDs and aspirin must be avoided; associated with the most severe and recurrent nasal polyposis.

Surgical removal of the fixed stapes and replacement with a prosthesis (e.g. piston from incus to oval window membrane) for otosclerosis; restores sound conduction; success rate >90% in experienced hands; risks include sensorineural hearing loss, perilymph gush, labyrinthitis, and chorda tympani nerve damage.

The parotid gland duct, approximately 5 cm long, passing anteriorly over the masseter muscle and piercing the buccinator to open opposite the upper second molar tooth; palpable when the parotid is obstructed (calculus, stricture).

The portion of the larynx above the true vocal folds, including the epiglottis, aryepiglottic folds, false vocal folds, and laryngeal ventricles; has rich lymphatic drainage → nodal spread occurs early in supraglottic carcinoma.

The spatial arrangement of frequency encoding along the basilar membrane: high-frequency sounds maximally displace the narrow, stiff base of the cochlea; low-frequency sounds displace the wide, flexible apex; the basis of audiometric frequency-specific hearing loss localisation.

The 'safe'/mucosal type of COM: central perforation of the pars tensa, mucoid/mucopurulent non-foul-smelling discharge, no cholesteatoma, conductive hearing loss; rarely causes life-threatening complications; medical treatment (aural toilet + ciprofloxacin drops) and myringoplasty are appropriate.

The drum-like membrane separating the EAC from the middle ear; comprises pars tensa (the main drum with three layers: epithelial, fibrous, mucosal) and pars flaccida (Shrapnell's membrane, lacking the fibrous layer, site of primary acquired cholesteatoma).

A reflex that stabilises gaze during head movement: semicircular canal signals (via CN VIII vestibular division and the medial longitudinal fasciculus) drive compensatory eye movements equal and opposite to the head movement, keeping the visual image stable on the retina.

A ring of lymphoid tissue at the junction of the nasal and oral cavities with the pharynx, comprising the adenoid (pharyngeal tonsil) posterosuperiorly, paired palatine tonsils laterally, lingual tonsil at the tongue base, and tubal tonsils near the Eustachian tube orifices.