4.2 Hearing loss Tinnitus and Dysequilibrium_2024_M Merven.pdf

Hearing Loss, Tinnitus and Vertigo Marc Merven ENT department Hearing Loss - Classification Conductive (CHL): Problem conducting sound into the inner ear (cochlea) Sensorineural (SNHL): Problem processing sound in the...

Hearing Loss, Tinnitus and Vertigo Marc Merven ENT department Hearing Loss - Classification Conductive (CHL): Problem conducting sound into the inner ear (cochlea) Sensorineural (SNHL): Problem processing sound in the CHL SNHL cochlea / CN VIII / central hearing pathways / brain Mixed Hearing loss Combination of both CHL and SNHL Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Conductive hearing loss (CHL) Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Conductive hearing loss (CHL) External Audiory Canal (EAC): Wax Otitis externa (swimmer’s ears) Exostoses (surfer’s ears) Microtia Tympanic Membrane (TM): Perforations Chronic suppurative otitis media (CSOM) Middle ear: Middle ear effusion(MEE)/ Otitis media with effusion(OME)/ Glue ear Ossicular chain fixation/ disruption Otosclerosis Trauma Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe CHL OBSTRUCTIVE EARWAX Causes: - narrow ear canals - some wax consistencies - elderly - earbuds Pt 1 – partially occluding wax Pt 2 – impacted wax No CHL CHL present Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe CHL Middle ear effusions (MEE) / glue ear / OME: Eustachian tube dysfunction  inadequate Ventilation of ME  -ve ME pressure  MEE Other factors Resolution stage of acute otitis media, reflux MEE causes impairment in movement the ear drum Mild / moderate conductive hearing loss Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe CHL Middle ear effusions / glue ear / OME Unusual in adults: May be as a result of preceding AOM If unilateral and persistent in adult Nasopharyngeal carcinoma is a possible cause of ET dysfunction Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe CHL Exostoses of EAC “Surfer’s ear” External auditory canal partially/near completely obstructed Minimal water, wax or infection results in complete closure and CHL Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe CHL Chronic suppurative otitis media Without cholesteatoma With cholesteatoma TB ear  TM perforations +/- Ossicular chain damage  Conductive Hearing Loss  (rarely SN HLoss (labyrinthitis)) Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe  CHL OTOSCLEROSIS Abnormal bone fixes stapes footplate Familial/spontaneous Conductive hearing loss Usually bilateral, with no cause No trauma No previous ear infections Normal “virgin” eardrum Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe CHL TYMPANOSCLEROSIS Very seldom causes H.Loss Scar tissue in tympanic membrane Occasionally involves the ossicles Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe CHL Congenital microtia: Defective development of ear: External auditory canal (EAC) Middle ear Inner ear Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Sensorineural hearing loss - SNHL Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe SNHL - causes Congenital Acquired Presbyaccusis – age related Trauma Physical Barotrauma Ototoxics Inflammatory/infective Labyrinthitis Viral (e.g. Mumps, HIV) Bacterial TB Autoimmune Idiopathic Neoplastic Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Diagnosis of SNHL in children H - Heredity E – Ear syndromes A - Asphyxia R – Treatments (ototoxics) I – Infections (meningitis) N – Neonatal ICU G – Growth (< 1500 gr) G – “Geelsug” - Jaundice Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Important facts about hearing loss in children: A child’s brain has a unique ability, “brain plasticity” for learning language / speech, which is of limited duration From birth to 6-10 years (most happen in 1st 5 years) The child must hear to learn speech Time lost is very difficult to catch up No hearing by 3-5 yrs means no speech forever Ideally, screening done by 1 month of age Diagnosis by 3 months and Intervention by 6 months for optimal speech development Similar to visual pathways, auditory pathways are ‘shut down’ or re- assigned if not developed in infancy Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Mechanisms involved in SNHL Absence/aplasia of the cochlear nerve Abnormal development of the cochlea Genetic anomalies of metabolisms within the cochlea Injury to the cochlear structure Damage to the hair cells in the cochlea Dysfunction or disruption of vascular supply to or within the cochlea Disruption of the nerve endings Compression of the nerve (CN VIII) Central/brain abnormalities Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe SNHL Cochlea form abnormality Normal Abnormal Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe SNHL Age-associated hearing loss / Presbyacusis Progressive loss of cochlear hair cells Reasonable to expect > 60 yrs old Characteristically: high tone/freq affected > low tone/freq (degeneration starts at base of cochlea) Speech discrimination affected Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe SNHL Noise-induced hearing loss Prolonged noise exposure:  80-90 dB requires protection (factories, industry) Head phones/head sets White noise baby devices Individual variation in susceptibility Sudden impact / blast / gunshot Often associated tinnitus Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe SNHL Ototoxicity Ear (& kidney) sensitive to many drugs. Causing permanent SNHL: Aminoglycosides (high dose, IV, ICUs, renal failure) Streptomycin Cytotoxics (chemotherapy) Temporary loss Loop diuretics Aspirin Can affect cochlea and/or vestibular organ Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Labyrinthitis ossificans Ossification of the labyrinth (cochlea and vestibule) Causes: Meningitis, trauma, AOM Suppuration within the cochlea and/or vestibule Inflammatory process resulting in fibrosis followed by ossification Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Menière’s Disease Pathology: Endolymphatic hydrops. (Increase in fluid pressure in the labyrinth) Associated symptoms: Episodic Vertigo lasting < 1 hour + H Loss + Tinnitus +/- sensation of pressure During attacks: Labyrinthine nystagmus H Loss Tinnitus Between attacks: Gradual hearing deterioration Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe  Vestibular schwannoma Asymmetric SNHL and/or tinnitus may suggest local pathology Tumour arising from the CN VIII (vestibular-cochlear nerve) in the internal auditory meatus SNHL/tinnitus either due to compression of the CN VIII or compression of the artery Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe SNHL Sudden sensorineural hearing loss ENT emergency Sudden unilateral/bilateral cochlear failure May / may not be associated tinnitus / vertigo In the absence of a clear causes: trauma, barotrauma, etc… then idiopathic Cause? - postulate: Viral Vascular ischaemia Autoimmune Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Tinnitus Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Tinnitus: what's the buzz? Tinnitus: Definition: Perceived sound with no external source Organised sounds are excluded Incidence: 20-30% population Physiological Transient pathological Permanent pathology Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Tinnitus: Classification: the 3 types of tinnitus 1. Non-pulsatile / “sensorineural”: (Shushing/ringing/cicada-like) – brain’s response to lack of input from ear 2. Pulsatile / vascular: ( in time with pulse) (Suggests ear is hearing nearby turbulent blood flow) 3. Intermittent odd local clicks or sounds Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Non-pulsatile tinnitus Perception of sound in the absence of an auditory stimulus ‘Shushing’/ ringing / cicada-like Brain’s response to input deprivation from the auditory periphery (cochlea and CN VIII) Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe The causes of non-pulsatile TINNITUS: Most commonly due to sensorineural hearing loss (SNHL) Conductive hearing loss can “unmask” / aggravate tinnitus Most common causes of SNHL Presbyacusis Noise-induced hearing loss - May be transient or permanent Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Other causes - SNHL - Congenital/perinatal causes of SNHL - Trauma - Physical or acoustic trauma - Inflammatory/autoimmune – Labyrinthitis, neuronitis – viral (incl COVID19), bacterial, autoimmune - Metabolic - Ototoxic drugs - Idiopathic +/- Sudden S-N H. Loss - Menières’s disease - Neoplastic - Vestibular Schwannoma - Psychosocial - Depression, anxiety, lack of sleep Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Pulsatile tinnitus In time with the heart beat Systemic cause (usually bilateral) Hyperthyroidism LOW, palpitations, hot flushes Pregnancy High output cardiac failure Cardiac murmurs Local causes Aneurysms AV malformations Glomus tumours Abherent veins or arteries Stenoses veins or arteries Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Intermittent odd local clicks or sounds External auditory canal: FB, insect Middle ear: Eustachian tube:”sticky”/patulous Muscle spasms: stapedius, tensor tympani Other local: Palatal myoclonus TMJ clicks Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Vertigo Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe  Equilibrium/balance: Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Various systems involved in integration of balance Input Output Cortical awareness: Cortex Sensation of Cerebellum + (dys)equilibrium: higher centres conscious reaction Visual adaptation: Control of Vision oculomotor activity Central integration Control of posture and motor skill Proprioception + peripheral sensation Autonomic nervous system Vestibular effects labyrinth Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Role of vestibular labyrinths in equilibrium: Most powerful organs providing information for balance The labyrinths on each side are paired and co-ordinated. Vestibular system has complex & multiple connections in CNS Under overriding “CENTRAL CONTROL” of brain Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe  DYSEQUILIBRIUM Pathological disturbance of balance/ equilibrium Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe DYSEQUILIBRIUM: Range of symptoms “Vertigo” (“true” vertigo) “hallucination of movement” vs “Giddiness” “Dizziness” balance disturbance but not “true” vertigo “Lightheadedness” vs “Faintness” “Blackouts” All these terms are used differently and usually vaguely, descriptively and indiscriminately by different people Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe DYSEQUILIBRIUM: Vertigo/giddiness/dizziness/etc… Range of pathology includes: Balance organs of inner ear CNS: cerebellum brainstem CVS: Ischaemia, syncopes, arrhythmias, hypertension Neck Metabolic – e.g. hyperventilation syndrome Psychogenic – e.g. panic attacks Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe DYSEQUILIBRIUM: Causes: central “CENTRAL” sites: PATHOLOGY e.g: Cerebrovascular accident Cerebral cortex Cerebellitis Neurological tracts Alcohol/barbiturates/tran- Cerebellum quilisers/anticonvulsants Brainstem CNS tumours Spinal cord Multiple sclerosis Age Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe DYSEQUILIBRIUM: Causes: vascular VASCULAR: Generalised syncopes/ fainting/ ‘drop attacks’: Vasovagal Postural hypotension Arrhythmias Ischaemia to the CNS Transient ischaemic attacks (TIAs) Vertebrobasilar insufficiency Vestibular end-artery Migraine Hypertension Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe DYSEQUILIBRIUM: Causes: others CERVICAL Occlusion of vertebral arteries E.g Osteophytes PSYCHOGENIC Panic attacks/ lightheadedness/ out-of-body experiences. HYPERVENTILATION SYNDROME Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe DYSEQUILIBRIUM: Causes: peripheral PATHOLOGY e.g: “PERIPHERAL” sites: Benign Paroxismal Labyrinth Positional Vertigo (BPPV) Vestibule Fracture of skull base Saccule Labyrinthitis Semicircular Canals Alcohol/ barbiturates/ Vestibular Nerve tran-quilisers/ anticonvulsants/ vestibulotoxics Menière’s disease Tumours Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe  Pathophysiology: Vestibular dysequilibrium: Sudden dysfunction of 1 labyrinth  its input not in agreement with healthy side and other senses  (Vestibular) dysequilibrium Symptoms: “Vertigo”: severe imbalance, sense of world turning Nausea/vomiting. Signs: Difficulty maintaining posture Vestibular (“Jerk”) nystagmus Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Vertigo Definition: A hallucination of movement – that implies that the patient feels that he/she is moving, without any movement taking place Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe  Vestibular/jerk nystagmus video Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe  NYSTAGMUS: + + ++ + + _    eye movement eye movement eye movement time time time vestibular and Slow drift (“vestibular”) central agree quick correction (“central”) Vestibular (“jerk”) nystagmus Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Nystagmus video Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Vestibular nystagmus: characteristics In setting of severe imbalance Horizontal / rotational Slow & fast phases (“jerk”) Easier to look in direction of slow drift Remains true to its direction (direction constant) Visual fixation can reduce it Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe  Central nystagmus: characteristics Irregular / pendular Direction changing “Uncharacteristic” / “weird” Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe  DYSEQUILIBRIUM: Pen pictures of different peripheral conditions Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe  Labyrinth Labyrinth Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Benign Paroxysmal Positional Vertigo (BPPV): Pathology: otoliths disturb balance organs in a semi-circular canal (commonly the posterior limb) Short episodes (lasting a few seconds) of rotational vertigo precipitated by specific head movements (e.g. turning the head to one side) Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Vestibular Neuronitis Pathology: Acute inflammation of the vestibular nerve resulting in an acute unilateral vestibular failure Results in Severe, continuous, debilitating rotational vertigo Nausea and vomiting No hearing disturbance Classic peripheral jerk nystagmus Gradual improvement over days to weeks as central compensation occurs Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Labyrinthitis Pathology: Viral/Bacterial/autoimmune inflammation of the labyrinth (cochlear & vestibule) Present with similar acute disabling vertigo and nystagmus as patients with vestibular neuronitis, but Cochlea involved: therefore associated hearing loss & tinnitus May see signs of the cause (e.g middle ear disease) Lasts hours to days until cause is treated Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Menière’s Disease Pathology: Endolymphatic hydrops (episodes of excess fluid/ pressure in the labyrinth – reason unknown) Presentation – Episodes/ attacks lasting < 1 hour of: - Vertigo (with nystagmus) + H Loss + Tinnitus - +/- sensation of pressure in the ears - Gradual hearing deterioration over time Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe Thank you Medicine and Health Sciences · EyeNzululwazi ngezoNyango neMpilo · Geneeskunde en Gesondheidswetenskappe