Hearing Loss Classification and Management

Conductive Hearing Loss

• The American Academy of Otolaryngology-Head and Neck Surgery states that conductive hearing loss occurs when pathology in the external auditory canal or middle ear blocks sound conduction to the inner ear 1, 2
• Common causes of conductive hearing loss include cerumen impaction, foreign bodies, stenosis, atresia, tympanic membrane perforation, middle ear effusion, cholesteatoma, ossicular discontinuity/fixation, and otosclerosis, as reported by the American Academy of Otolaryngology-Head and Neck Surgery 1, 2
• The prognosis for conductive hearing loss is generally good with appropriate intervention, with many causes being medically or surgically correctable, according to the American Academy of Otolaryngology-Head and Neck Surgery 1

Sensorineural Hearing Loss

• The American Academy of Otolaryngology-Head and Neck Surgery reports that sensorineural hearing loss involves dysfunction of the inner ear, cochlear nerve, or central auditory pathways, resulting from damage to hair cells in the cochlea, auditory nerve, or central auditory centers 1, 3
• Age-related hearing loss (presbycusis) is the most common type in adults, typically beginning after age 50 and increasing in prevalence with age, affecting 1 in 3 adults aged 65-74 and nearly 50% of those over 75, as stated by the American Academy of Otolaryngology-Head and Neck Surgery 3, 4
• The American Academy of Otolaryngology-Head and Neck Surgery notes that presbycusis is typically bilateral, symmetric, and gradually progressive, with a permanent and progressive prognosis, and management focuses on amplification and rehabilitation 3, 4

Mixed Hearing Loss and Special Considerations

• The American Academy of Otolaryngology-Head and Neck Surgery states that mixed hearing loss combines elements of both conductive and sensorineural hearing loss, involving dysfunction in both the sound conduction pathway and the sensorineural components 1
• Asymmetric sensorineural hearing loss requires further evaluation as it may indicate serious underlying pathology, such as retrocochlear pathology like vestibular schwannoma or meningioma, according to the American Academy of Otolaryngology-Head and Neck Surgery 1, 2
• The American Academy of Otolaryngology-Head and Neck Surgery recommends that patients with significant asymmetric hearing loss, conductive/mixed hearing loss, or poor word recognition should be referred for specialized evaluation 1, 5

Clinical Implications

• Early identification and appropriate referral are crucial for optimal outcomes, as stated by the American Academy of Otolaryngology-Head and Neck Surgery 1, 3
• The American Academy of Otolaryngology-Head and Neck Surgery recommends regular monitoring (at least every 3 years) for patients with known hearing loss 6
• Patient education about the impact of hearing loss on communication, safety, cognition, and quality of life is essential, according to the American Academy of Otolaryngology-Head and Neck Surgery 1, 6

Management of Mixed Hearing Loss with Attic Retraction

Initial Assessment and Diagnosis

• The American Academy of Otolaryngology-Head and Neck Surgery recommends that clinicians evaluate and refer patients with conductive or mixed hearing loss for specialized management, as the presence of mixed hearing loss combined with attic retraction represents a serious clinical scenario requiring immediate specialist attention 7

Key Diagnostic Steps

• Distinguishing hearing loss type through physical examination and tuning fork tests (Weber and Rinne) is necessary to confirm the mixed nature of the hearing loss, as recommended by the American Academy of Otolaryngology-Head and Neck Surgery 8, 9
• Obtaining comprehensive audiometry, including pure tone thresholds, speech audiometry, and tympanometry, is crucial to quantify both the conductive and sensorineural components of the hearing loss 7

Surgical Management Strategy

• Follow-up every 3-6 months with otoscopy and audiometry is recommended for stable, non-progressive retractions without evidence of cholesteatoma 10

Addressing the Mixed Hearing Loss

• Audiologic rehabilitation should be offered for residual sensorineural hearing loss, as part of the management strategy for mixed hearing loss 11
• Hearing amplification may be necessary if significant sensorineural loss persists post-operatively, according to the American Academy of Otolaryngology-Head and Neck Surgery 7

Monitoring and Follow-Up

• Obtaining follow-up audiometry at conclusion of treatment and within 6 months is recommended to assess the outcome of the management strategy 11

Hearing Loss Evaluation and Management

Introduction to Hearing Loss

• The American Academy of Otolaryngology-Head and Neck Surgery recommends distinguishing between conductive and sensorineural hearing loss, as management pathways are completely different and time-sensitive treatment windows may be closing 12

Diagnostic Evaluation

• Pure tone audiometry with air and bone conduction thresholds is essential to quantify hearing loss and determine type, according to the American Academy of Otolaryngology-Head and Neck Surgery 12
• Otoscopic examination will likely show abnormalities in conductive hearing loss, including middle ear effusion, tympanic membrane retraction, cerumen impaction, or other structural pathology 12
• Otoscopic examination will typically be normal in sensorineural hearing loss 12

Sensorineural Hearing Loss

• This represents a potential otologic emergency, especially if sudden onset, and requires immediate evaluation and treatment 13, 14
• Time-sensitive treatment window: corticosteroids are most effective within 2 weeks of symptom onset, according to the American Academy of Otolaryngology-Head and Neck Surgery 13, 14
• Approximately one-third to two-thirds of sudden sensorineural hearing loss patients may recover spontaneously within 2 weeks, but those without improvement in the first 2 weeks are unlikely to show significant recovery 13, 14

Treatment Pathways

• Corticosteroids may be offered as initial therapy if within 2 weeks of symptom onset in sudden sensorineural hearing loss, according to the American Academy of Otolaryngology-Head and Neck Surgery 13, 14
• Intratympanic corticosteroids can be offered as salvage therapy if oral steroids fail or are contraindicated in sudden sensorineural hearing loss 13, 14
• MRI of brain and internal auditory canals should be obtained to rule out vestibular schwannoma in sudden sensorineural hearing loss 13, 14
• Follow-up audiometry within 6 months is recommended to assess treatment outcome in sudden sensorineural hearing loss 15

Diagnostic Criteria and Evaluation of Mixed Hearing Loss

Definition

• Mixed hearing loss is defined as the simultaneous presence of conductive and sensorineural components in the same ear, requiring audiometric confirmation with abnormal air‑ and bone‑conduction thresholds. American Academy of Otolaryngology‑Head and Neck Surgery. 16
• The conductive component reflects pathology in the external auditory canal, tympanic membrane, or middle ear that impedes sound transmission. American Academy of Otolaryngology‑Head and Neck Surgery. 17
• The sensorineural component reflects dysfunction of the cochlea, auditory nerve, or central auditory pathways occurring concurrently. American Academy of Otolaryngology‑Head and Neck Surgery. 17

Audiometric Evaluation

• Comprehensive audiometric testing that demonstrates the characteristic mixed‑loss pattern is required for diagnosis. American Academy of Otolaryngology‑Head and Neck Surgery. 18
• Pure‑tone audiometry should include air‑ and bone‑conduction measurements across the frequency range of 250 Hz to 8000 Hz. American Academy of Otolaryngology‑Head and Neck Surgery. 18

Speech Audiometry

• Speech‑recognition threshold (SRT) and word‑recognition scores (WRS) should be obtained to evaluate functional hearing ability. American Academy of Otolaryngology‑Head and Neck Surgery. 18
• Disproportionately poor word‑recognition scores relative to the pure‑tone average may indicate retrocochlear pathology and prompt additional work‑up. American Academy of Otolaryngology‑Head and Neck Surgery. 19

Physical Examination

• Otoscopic examination typically reveals middle‑ear abnormalities such as effusion, tympanic‑membrane retraction or perforation, cerumen impaction, cholesteatoma, or other structural pathology. American Academy of Otolaryngology‑Head and Neck Surgery. 16
• Tuning‑fork testing (Weber and Rinne) assists in distinguishing the mixed nature by demonstrating both conductive and sensorineural components. American Academy of Otolaryngology‑Head and Neck Surgery. 16

Tympanometry

• Tympanometry is essential for assessing middle‑ear function and confirming the conductive component of mixed loss. American Academy of Otolaryngology‑Head and Neck Surgery. 18

Referral, Imaging, and Management Considerations

• Asymmetric mixed hearing loss warrants immediate specialized evaluation to exclude serious underlying lesions such as vestibular schwannoma or other retrocochlear pathologies. American Academy of Otolaryngology‑Head and Neck Surgery. 18
• The American Academy of Otolaryngology‑Head and Neck Surgery recommends referral of patients with conductive or mixed hearing loss for specialized management due to the potential seriousness of the clinical scenario. American Academy of Otolaryngology‑Head and Neck Surgery. 18
• Temporal‑bone imaging (high‑resolution CT for conductive pathology or MRI with gadolinium for sensorineural and retrocochlear assessment) should be considered when the etiology is unclear or surgical intervention is contemplated. American Academy of Otolaryngology‑Head and Neck Surgery. 18