neurology IV: disorders of special senses

Usually granulomatous anterior uveitis (mutton-fat keratic precipitates, iris nodules).

most common ocular manifestation of sarcoidosis

Less common, but children with juvenile idiopathic arthritis (JIA, esp. oligoarticular type, ANA+) often develop chronic anterior uveitis.

most common uveitis associated with rheumatoid arthritis

Rare in SLE (unlike sarcoidosis or JIA).

is uveitis common in SLE?

uveitis

inflammation of the uvea causing swelling and irritation

Retinal vasculitis, cotton-wool spots, retinal artery/vein occlusions (from immune complex vasculitis or antiphospholipid antibodies).

ocular findings associated with SLE

candle-wax drippings

Sarcoidosis findings of granuomatous uveitis

conductive hearing loss

Reduced sound intensity, but clarity preserved; often improves with volume

Sensorineural hearingloss

-Dysfunction of inner ear (cochlea/hair cells) or CN VIII

-Loss of both intensity and clarity, especially difficulty with speech discrimination

central hearing loss

-Lesion in auditory cortex or central pathways

-Difficulty interpreting sound despite intact peripheral system; often associated with neurologic findings

Cerumen impaction, otitis media, otitis externa, tympanic membrane perforation, otosclerosis

most common causes of conductive hearing loss

Presbycusis (age-related), noise-induced, Meniere's disease, vestibular schwannoma, ototoxic drugs (aminoglycosides, cisplatin, loop diuretics)

most common causes of sensorineurall hearing loss

Chronic otitis media with cholesteatoma, trauma, advanced otosclerosis

most common causes of mixed hearing loss

Stroke (temporal lobe), multiple sclerosis, brainstem tumors, cortical lesions

most common causes of central hearing loss

Rinne: bone > air, Weber lateralizes to affected ear

Rinne/Weber findings associated with conductive hearing loss

Frequent otitis media, Eustachian tube dysfunction, family history of otosclerosis.

risk factors for conductive hearing loss

sensorineural hearing loss

History: Progressive difficulty understanding speech, especially in noisy environments; tinnitus.

Age (presbycusis), chronic noise exposure, ototoxic meds, family history.

risk factors of SNHL

Rinne air > bone (normal), Weber lateralizes to unaffected ear.

Rinne/Weber findings associated with SNHL

History: Combination (e.g., chronic infection + gradual decline in clarity).

Risk factors: Chronic otitis media, long-standing middle ear disease.

history + risk factors associated with mixed hearing loss

Prior stroke, MS, brain tumors, trauma.

risk factors of central hearing loss

air vs bone conduction

the Rinne tests

lateralization (conductive → affected ear; SNHL → unaffected ear

Weber tests

conductive hearing loss

Air conduction worse than bone conduction; air-bone gap present.

Sensorineural hearing loss

Both air and bone conduction reduced, no gap.

otoacoustic emissions

ewborn screening; evaluates cochlear (outer hair cell) function.

aminoglycosides, cisplatin, loop diuretics

classic ototoxic medications

High-dose corticosteroids (oral or intratympanic)

treatment of suddent SNHL

audiogram

cornerstone test for hearing loss

Onset: Sudden (hours to days), unilateral facial weakness.

Laterality: Typically unilateral, rarely bilateral.

typical onset of bell;s palsy

Inability to close eye, raise eyebrow, smile, frown, or puff cheek on affected side.

Drooping of mouth → drooling.

Altered taste (anterior 2/3 tongue via chorda tympani)

Dry eye (↓ lacrimation) or dry mouth (↓ salivation).

no other neurologic deficits

typical symptoms of Bell's palsy

Bell’s Palsy = LMN lesion of CN VII → forehead not spared.

Stroke = UMN lesion → forehead spared (bilateral cortical innervation).

main differentiator of Bell's palsy from stroke

hyperacusis

excessively sensitive hearing

-associated with Bell's palsy on affectedd side

Bell's phenomenon

fluttering of the eyes upward when closed eyelids are opened by the examiner

lyme disease, tumors, HIV, sypphilis

potential secondary causes of Bell's palsy

Ramsay Hunt Syndrome (Herpes Zoster Oticus)

VZV causing facial palsy + vesicular rash in ear

Heerfordt's syndrome

Sarcoid associated with parotid gland enlargement, uveitis, fever and cranial nerve palsies

trigeminal neuralgia

Severe, brief, lancinating unilateral facial pain (seconds-minutes).

Triggered by light touch, chewing, talking.

Causes: idiopathic (vascular loop compression), MS (demyelination), tumors.

glossopharyngeal neuralgia

Severe unilateral throat, ear, tonsillar fossa pain.

Triggered by swallowing, coughing, talking.

Causes: idiopathic, vascular compression, tumors.

HSV-1

virus sometimes impllicated with Bell's palsy

often bilateral facial palsy

palsy associated with Lyme disease

Incomplete recovery or permanent weakness.

Aberrant regeneration (synkinesis: involuntary eye closure with smiling).

Exposure keratopathy (inability to close eye → corneal ulcer).

complicatioins of Bell's palsy

Synkinesis

involluntary eye closure with smiling (comp of Bell's palsy, grammy has this)

Oral corticosteroids (prednisone) within 72 hours of onset.

-eye protection via artificial tears, taping at night

first liine treatment of Bell's palsy