OMSB ENT (OEENT) cheat sheet

Epistaxis: most bleeds arise from Kiesselbach plexus (Little area) on the anterior septum; first-line is direct pressure for 10–15 minutes plus topical vasoconstrictor, then chemical or electrocautery of a visible anterior vessel; posterior bleeds (sphenopalatine artery) present with blood running down the throat and often need packing or arterial ligation/embolization.

Sudden sensorineural hearing loss: defined as ≥30 dB loss across three contiguous frequencies occurring within 72 hours; treat as an emergency - oral or intratympanic corticosteroids, MRI to exclude retrocochlear pathology (vestibular schwannoma), and audiometry at presentation and follow-up.

Acute otitis media diagnostic triad: acute onset of symptoms, middle-ear effusion (bulging or reduced mobility on pneumatic otoscopy), and middle-ear inflammation; routine antibiotics are not required for all cases - observe for 48–72 hours in selected children ≥2 years with nonsevere illness, but treat with amoxicillin (high dose) when severe, bilateral in young children, or otorrhea is present.

Vertigo: distinguish peripheral from central. Peripheral features include horizontal-torsional nystagmus suppressed by visual fixation, positive head impulse test, and no skew deviation; central features include vertical or direction-changing nystagmus, normal head impulse, skew deviation, and focal neurologic signs (HINTS exam).

Benign paroxysmal positional vertigo: diagnosed by Dix–Hallpike maneuver (posterior canal) showing upbeating torsional nystagmus with latency and fatigability; treated with canalith repositioning (Epley). Horizontal canal BPPV shows horizontal geotropic or ageotropic nystagmus on supine roll test.

Tonsillectomy indications: recurrent throat infection meeting frequency criteria (e.g., ≥7 episodes in 1 year, ≥5 per year for 2 years, or ≥3 per year for 3 years), obstructive sleep-disordered breathing, or suspicion of malignancy in asymmetric enlargement; post-tonsillectomy hemorrhage is the most feared complication and can be primary (within 24 h) or secondary (days 5–10).

Neck masses: in adults, a persistent neck mass is malignancy until proven otherwise - perform flexible nasolaryngoscopy and fine-needle aspiration; squamous cell carcinoma (often HPV-related oropharyngeal) is the most common cause of a malignant neck mass in adults, whereas branchial cleft cysts and thyroglossal duct cysts are common congenital causes in children.

Airway emergency: stridor is a sign of upper airway obstruction (inspiratory stridor suggests laryngeal level); in a child with suspected epiglottitis or croup, avoid agitating the patient, do not examine the throat with a tongue blade if epiglottitis is suspected, and secure the airway in a controlled setting with anesthesia/ENT backup.

Hearing loss classification: conductive loss shows air-bone gap with normal bone conduction; sensorineural loss shows both air and bone thresholds reduced with no gap; mixed loss shows a gap plus reduced bone conduction. Tuning forks: Rinne negative in conductive loss; Weber lateralizes to the affected ear in conductive loss and to the better ear in sensorineural loss.

Hoarseness lasting >3 weeks in an adult requires laryngoscopy to exclude laryngeal carcinoma, regardless of smoking history; red flags include dysphagia, odynophagia, otalgia with normal ear exam, and neck mass.

Chronic rhinosinusitis diagnosis requires ≥12 weeks of symptoms plus objective evidence of mucosal inflammation (endoscopy or CT); initial management is saline irrigation plus intranasal corticosteroids, with antibiotics reserved for documented bacterial exacerbations.

Obstructive sleep apnea: screen with Epworth Sleepiness Scale and overnight polysomnography; apnea-hypopnea index ≥5 with symptoms or ≥15 regardless of symptoms defines OSA; first-line therapy for moderate-severe disease is CPAP, with surgery (e.g., tonsillectomy in children, uvulopalatopharyngoplasty in selected adults) as adjunct.

Salivary gland swelling: parotid tumors are most often benign pleomorphic adenoma; a painful, rapidly growing mass with facial nerve palsy suggests malignancy. Fine-needle aspiration guides management; sialolithiasis causes meal-related pain and is managed with hydration, sialogogues, and sialendoscopy or excision if recurrent.

Otitis externa: caused most often by Pseudomonas aeruginosa or Staphylococcus aureus after water exposure; treat with topical antibiotic drops (e.g., ciprofloxacin or aminoglycoside) plus aural toilet; avoid aminoglycoside drops if tympanic membrane perforation is suspected, and use a wick if the canal is swollen.

Cholesteatoma: painless otorrhea with a marginal/attic retraction pocket and conductive hearing loss; it is locally destructive and does not resolve with medical therapy - treatment is surgical (tympanomastoidectomy).

Facial nerve palsy: Bell palsy is idiopathic and peripheral (involves the entire hemiface, including forehead); corticosteroids within 72 hours improve outcomes. Forehead sparing or other cranial neuropathies suggest central lesion or parotid/skull-base malignancy.

Pediatric stridor: croup (barking cough, inspiratory stridor, steeple sign) is treated with dexamethasone and nebulized epinephrine for moderate-severe cases; epiglottitis (drooling, tripod positioning, thumb sign) is a true airway emergency requiring intubation and IV antibiotics.

Allergic rhinitis: diagnose clinically with confirmatory testing when needed; first-line therapy is intranasal corticosteroids plus second-generation oral antihistamines; intranasal decongestants should not exceed 3–5 days to avoid rhinitis medicamentosa.

Middle ear anatomy: the ossicular chain transmits sound from the tympanic membrane to the oval window (malleus–incus–stapes); the Eustachian tube equalizes pressure and drains the middle ear, and dysfunction underlies most middle-ear effusion.

Cochlear tonotopic organization: high frequencies are encoded at the base and low frequencies at the apex; this explains the pattern of noise-induced hearing loss (4 kHz notch) and the frequency mapping of cochlear implants.

Cranial nerves in ENT: CN VII (facial) exits via the stylomastoid foramen; CN IX (glossopharyngeal) mediates the gag reflex afferent; CN X (vagus) provides vocal cord motor innervation via the recurrent laryngeal nerve, which loops around the aortic arch on the left and the subclavian artery on the right - left-sided injury is more common in thoracic disease.

Laryngeal examination: indirect laryngoscopy or flexible nasolaryngoscopy visualizes the vocal folds; normal phonation requires symmetrical mucosal waves and complete glottic closure; lesions on the true vocal fold with impaired mobility raise concern for malignancy.

Neck levels (surgical): Level I submental/submandibular, II upper jugular, III mid jugular, IV lower jugular, V posterior triangle, VI anterior (central) compartment - relevant for thyroid, laryngeal, and nodal staging.

Tympanometry types: Type A normal (peak near 0 daPa), Type B flat (effusion, perforation, or mass), Type C negative pressure (Eustachian tube dysfunction); acoustic reflex testing assesses the stapedial reflex arc.

Tuning fork tests: Rinne compares air versus bone conduction at the mastoid; Weber compares bone conduction between ears; Schwabach compares patient to examiner - useful for quick bedside classification of hearing loss.

Smell and taste: olfactory epithelium sits in the cribriform plate region; anosmia after head trauma may indicate cribriform plate fracture with risk of CSF leak (halo sign, β2-transferrin).