Clin Med: Otitis, Hearing, Equilibrium

Cerumen Impaction

Excessive accumulation of normal, protective cerumen that causes symptoms or prevents a necessary ear canal examination, frequently exacerbated when cotton swabs or digital manipulation push wax deeper into the canal. It presents clinically with hearing loss, ear fullness or pressure, otalgia, itching, or tinnitus.

Ear Canal Foreign Bodies

Exogenous objects (such as beads, toys, paper, food, or insects) retained within the external auditory canal, occurring most commonly in pediatric patients. Pathophysiology involves canal obstruction or mucosal irritation, presenting as an asymptomatic finding or with ear pain, hearing loss, otorrhea, or bleeding.

Otitis Externa

Acute bacterial inflammation or infection of the external auditory canal, most frequently caused by Pseudomonas aeruginosa or Staphylococcus aureus, with key risk factors including water exposure, canal trauma (e.g., cotton swabs, scratching), and earbud or hearing aid use. It presents clinically with otalgia, pruritus, ear fullness, otorrhea, severe pain elicited by manipulating the tragus or pinna, and canal erythema and edema with exudate or debris that may obscure the tympanic membrane.

Necrotizing Otitis Externa

Severe, invasive bacterial infection of the external auditory canal that extends to adjacent skull base structures causing skull-base osteomyelitis, occurring most often in older adults with diabetes or immunocompromised individuals infected with Pseudomonas aeruginosa. It presents clinically with severe, persistent otalgia (characteristically worse at night), persistent otorrhea despite topical therapy, granulation tissue in the ear canal, and potential cranial nerve deficits in advanced disease.

Acute Otitis Media (AOM)

Acute infection and inflammation of the middle ear space, typically developing after a viral upper respiratory infection causes Eustachian tube dysfunction and middle-ear fluid accumulation, leading to bacterial superinfection (most commonly Streptococcus pneumoniae, nontypeable Haemophilus influenzae, or Moraxella catarrhalis). It presents clinically with acute otalgia, fever, URI symptoms, decreased hearing, ear-tugging and irritability in infants, otorrhea if the tympanic membrane perforates, and hallmark otoscopic findings of a bulging tympanic membrane, middle-ear effusion, decreased TM mobility, and loss of normal landmarks.

Otitis Media with Effusion (OME)

Presence of middle-ear fluid without signs or symptoms of acute infection, commonly developing after an episode of acute otitis media, during Eustachian tube dysfunction, or following a viral URI. It presents clinically without fever or acute otalgia, manifesting instead as ear fullness, popping, or conductive hearing loss, with otoscopy demonstrating a dull or retracted tympanic membrane, air-fluid levels or bubbles, and decreased TM mobility on pneumatic otoscopy.

Chronic Suppurative Otitis Media (CSOM)

Chronic middle-ear inflammation defined by persistent or recurrent otorrhea flowing through a perforated tympanic membrane, typically following recurrent or inadequately treated middle-ear infections and most commonly involving Pseudomonas aeruginosa or Staphylococcus aureus. It presents clinically with persistent or recurrent purulent ear discharge and conductive hearing loss, usually causing little to no ear pain unless an acute exacerbation occurs.

Eustachian Tube Dysfunction

Impaired patency or opening mechanism of the Eustachian tube preventing normal middle-ear ventilation and pressure equalization, frequently triggered by viral URIs, allergic rhinitis, or anatomical factors. It presents clinically with ear fullness, popping, pressure, muffled hearing, and symptom exacerbation during ambient pressure changes.

Otosclerosis

Abnormal bone remodeling of the otic capsule that most commonly fixes the stapes footplate at the oval window, preventing normal acoustic vibration and sound transmission into the inner ear. It presents clinically in young to middle-aged adults (frequently bilateral and familial) as progressive conductive hearing loss with a normal otoscopic exam, though extension into the cochlea can additionally produce sensorineural hearing loss.

Barotrauma

Middle-ear mucosal injury resulting from a failure to equalize pressure between the middle ear cavity and ambient atmospheric pressure, occurring most commonly during flight descent or diving in the setting of Eustachian tube dysfunction, URI, or nasal congestion. It presents clinically with ear pain, pressure, fullness, popping, and muffled hearing, with otoscopy showing tympanic membrane retraction, erythema, middle-ear fluid, hemotympanum, or TM perforation, as well as potential vertigo or sensorineural hearing loss if inner-ear barotrauma occurs.

Cholesteatoma

Non-neoplastic accumulation of keratinizing squamous epithelium within the middle ear and mastoid, most commonly acquired when chronic Eustachian tube dysfunction generates negative pressure leading to a tympanic membrane retraction pocket, or secondary to chronic suppurative otitis media. Pathophysiology involves expanding keratin accumulation that progressively erodes surrounding ossicles and bone, presenting clinically with persistent or recurrent foul-smelling otorrhea, conductive hearing loss, and otoscopic visualization of a retraction pocket containing pearly white keratin debris.

Mastoiditis

Serious suppurative complication of acute otitis media where bacterial infection extends directly from the middle ear cavity into the mastoid air cells, potentially causing bony septal destruction. It presents clinically with fever, otalgia, postauricular erythema, swelling, tenderness, protrusion or displacement of the auricle, persistent AOM findings, and CT evidence of mastoid opacification with loss of bony septa.

Middle Ear Paraganglioma (Glomus Tumor)

Rare, highly vascular, and typically benign neuroendocrine tumor arising within the middle ear cavity (glomus tympanicum) or jugular bulb (glomus jugulare). It presents clinically with the classic symptoms of pulsatile tinnitus and conductive hearing loss, with otoscopy revealing a reddish vascular mass visible behind the tympanic membrane and larger lesions causing lower cranial nerve neuropathies.

Hyperacusis

Reduced tolerance to ordinary environmental sounds causing normal-intensity everyday noise to seem excessively loud or uncomfortable, associated with acoustic trauma, noise exposure, migraine, tinnitus, or auditory disorders. It presents clinically as sound intolerance occurring even in individuals with completely normal hearing thresholds.

Tinnitus

Perception of sound in the ear or head without an external acoustic source, most commonly subjective and nonpulsatile, associated with age-related hearing loss, noise exposure, ototoxic medications, or underlying ear pathology. It presents clinically as persistent or intermittent ringing, buzzing, or hissing sounds in the ear, frequently accompanying hearing loss.

Pulsatile Tinnitus

Perception of a vascular sound in the ear that is synchronous with the patient's heartbeat, indicating an underlying vascular cause such as a paraganglioma, arteriovenous malformation/fistula, vascular stenosis, or elevated intracranial pressure. It presents clinically as a rhythmic whooshing or thumping sound matched to the pulse, serving as a red flag that requires targeted vascular evaluation.

Vertigo

Illusion of motion when no motion is occurring or an exaggerated sensation of motion, stemming from asymmetrical neural input between vestibular pathways. Pathophysiology is categorized as peripheral (involving the inner ear or vestibular nerve) or central (involving the brainstem or cerebellum), presenting clinically with sensations of spinning, tilting, or movement, often accompanied by nausea, vomiting, and nystagmus (horizontal/torsional in peripheral disease versus vertical or direction-changing in central etiology).

Labyrinthitis

Inflammatory process involving both the vestibular and cochlear structures of the inner ear, typically caused by a viral or postviral process (or rarely bacterial extension from otitis media or meningitis). It presents clinically as an acute, continuous, severe vertigo lasting days alongside unilateral sensorineural hearing loss, tinnitus, nausea, vomiting, and gait instability.

Ménière's Disease

Inner-ear disorder associated with endolymphatic hydrops, wherein excess accumulation and elevated pressure of endolymph fluid within the inner ear causes progressive structural damage. Pathophysiology manifests clinically as recurrent, spontaneous episodes of vertigo lasting 20 minutes to 12 hours, accompanied by fluctuating unilateral sensorineural hearing loss, tinnitus, and aural fullness.

Benign Paroxysmal Positional Vertigo (BPPV)

Vestibular disorder caused by displaced otoconia ("ear crystals") entering a semicircular canal (most frequently the posterior canal). Pathophysiology involves free-floating otoconia inappropriately deflecting the cupula during head movement, presenting clinically with brief episodes of vertigo (lasting <1 minute) provoked by head position changes (such as rolling over in bed, lying back, looking up, or bending over) without hearing loss or tinnitus, and confirmed via the Dix-Hallpike maneuver.

Conductive Hearing Loss

Hearing impairment caused by impaired transmission of sound waves through the external ear canal or middle ear structures. Pathophysiology involves etiologies such as cerumen impaction, foreign body, otitis externa, otitis media with effusion, Eustachian tube dysfunction, tympanic membrane perforation, or otosclerosis, presenting as reduced sound volume or muffled hearing with preserved nerve conduction.

Sensorineural Hearing Loss

Hearing impairment caused by dysfunction or damage involving the sensory hair cells of the cochlea or the auditory neural pathways of cranial nerve VIII. Pathophysiology encompasses age-related degeneration (presbycusis), noise exposure, ototoxic drugs, inner ear inflammation, or retrocochlear tumors, presenting clinically as loss of sound clarity and speech comprehension.

Sudden Sensorineural Hearing Loss

Acute, unexplained loss of sensorineural hearing developing over 72 hours or less, most commonly idiopathic in origin. It presents clinically as rapid unilateral hearing loss, frequently accompanied by tinnitus, ear fullness, or vertigo, representing an urgent condition requiring prompt audiometric evaluation.

Vestibular Schwannoma (Acoustic Neuroma)

Benign, slow-growing tumor arising from the Schwann cells of the vestibular portion of cranial nerve VIII, usually occurring sporadically and unilaterally (or bilaterally in Neurofibromatosis type 2). Pathophysiology involves progressive compression of nerve structures within the internal auditory canal and cerebellopontine angle, presenting clinically with progressive unilateral sensorineural hearing loss, unilateral tinnitus, and imbalance, with larger lesions causing facial numbness (CN V), facial weakness (CN VII), or ataxia