Can carotid artery stenosis cause changes to hearing?

Carotid Artery Stenosis and Hearing Changes

Yes, carotid artery stenosis can cause changes to hearing, including hearing loss, tinnitus, and other auditory disturbances. 1

Pathophysiological Mechanisms

• Carotid artery stenosis can lead to reduced blood flow through the carotid arteries, causing problems in the hearing organ that manifest as receptive cochlear-extracochlear hearing damage 1
• The ischemic mechanism within the inner ear region may lead to early non-specific symptoms of atherosclerosis of large vessels 1
• Hearing changes may be part of the spectrum of non-specific symptoms that can occur with carotid stenosis, alongside other neurological manifestations 2

Clinical Manifestations of Hearing Changes in Carotid Stenosis

• Patients with carotid artery stenosis may experience:

  • Hearing loss (which may be subtle and not always clinically apparent) 1
  • Tinnitus (including pulsatile tinnitus in some cases) 3
  • Abnormalities in audiological testing even without subjective hearing complaints 1

• These symptoms may occur alongside other more recognized symptoms of carotid stenosis such as:

  • Hemispheric (cortical) ischemia 2
  • Amaurosis fugax (temporary vision loss) 2
  • Motor or sensory deficits 2

Diagnostic Considerations

• Audiological abnormalities detected in patients with carotid stenosis include:

  • Abnormal tone threshold audiometry 1
  • Abnormal stapedius muscle reflexes 1
  • Altered brainstem auditory evoked potentials 1

• When evaluating a patient with unexplained hearing changes, especially in those with vascular risk factors, carotid artery disease should be considered in the differential diagnosis 1

• Duplex ultrasound (DUS) is commonly used as the first step to detect extracranial carotid artery stenosis 2

Important Clinical Correlations

• Hearing disturbances appear to have similar severity whether the stenosis affects the internal carotid artery or vertebral artery 1

• Carotid endarterectomy has been associated with postoperative voice problems and may result in recurrent laryngeal nerve damage in up to 6% of patients, which could indirectly affect hearing perception 2

• Pulsatile tinnitus specifically has been reported as a symptom of carotid artery stenosis, with cases showing immediate resolution following treatment of the stenosis 3

Management Implications

• In patients presenting with unexplained hearing changes, especially those with vascular risk factors, screening for carotid artery stenosis may be warranted 1

• Management of carotid stenosis follows standard protocols based on:

  • Presence of symptoms related to the affected carotid artery 2
  • Degree of internal carotid artery stenosis 2
  • Patient age, gender, comorbidities, and life expectancy 2

• All patients with carotid artery disease should receive:

  • Antiplatelet therapy (low-dose aspirin or clopidogrel in case of aspirin intolerance) 2
  • Statin medication to reduce LDL cholesterol below 100 mg/dL 2
  • Blood pressure management 2
  • Smoking cessation interventions 2

Clinical Pitfalls and Caveats

• Hearing changes due to carotid stenosis may be subtle and not always explicitly clinically expressed as hearing loss 1

• These auditory symptoms may be overlooked or attributed to age-related hearing loss, particularly in older patients who are also at higher risk for carotid stenosis 1

• When evaluating patients with unexplained hearing changes, particularly those with vascular risk factors, clinicians should consider carotid artery stenosis in the differential diagnosis 1

• Hearing changes may sometimes be an early indicator of clinically significant stenosis before more typical neurological symptoms develop 1