What is the recommended workup for a patient presenting with pulsation tinnitus?

Workup for Pulsatile Tinnitus

For patients presenting with pulsatile tinnitus, a CT angiography or MR angiography should be performed as the primary imaging modality to identify the underlying cause, which can be found in more than 70% of cases with thorough evaluation. 1, 2

Initial Evaluation

History and Physical Examination

• Determine characteristics of tinnitus:
  • Confirm pulsatile nature (synchronous with heartbeat)
  • Unilateral vs bilateral
  • Duration of symptoms
  • Associated symptoms (hearing loss, vertigo, neurological symptoms)
  • Impact on quality of life

Otoscopic Examination

• Visualize ear canals and tympanic membranes to identify:
  • Visible vascular abnormalities
  • Middle ear masses
  • Tympanic membrane perforation
  • Cerumen impaction

Additional Physical Examination

• Auscultation of ears, neck, and skull to detect objective bruits
• Compression of ipsilateral jugular vein (if this abolishes the tinnitus, venous cause is likely)
• Head positioning tests

Imaging Studies

First-Line Imaging

• CT angiography or MR angiography is the recommended first-line imaging for pulsatile tinnitus 1
• These modalities can identify:
  • Vascular abnormalities (arteriovenous fistulae, arteriovenous malformations)
  • Vascular tumors (glomus tumors/paragangliomas)
  • Vascular stenoses
  • Venous anomalies

Additional Imaging Based on Clinical Suspicion

• MRI with contrast of internal auditory canals if:

  • Unilateral tinnitus with asymmetric hearing loss
  • Suspicion of vestibular schwannoma

• High-resolution CT of temporal bones if:

  • Suspicion of temporal bone pathology
  • Dehiscent jugular bulb
  • Superior semicircular canal dehiscence

Specialist Referrals

Immediate ENT Referral

• All patients with pulsatile tinnitus should be referred to an otolaryngologist 1
• Urgent referral if:
  • Visible abnormality on otoscopic examination
  • Associated focal neurological symptoms
  • Sudden hearing loss

Additional Referrals

• Audiologist: For comprehensive hearing evaluation
• Neurology/Neurosurgery: If vascular malformation or intracranial hypertension is suspected
• Interventional Radiology: For potential treatment of vascular causes

Common Etiologies to Consider

Vascular Causes (Most Common)

• Arterial: Atherosclerosis, carotid stenosis, arterial dissection, fibromuscular dysplasia
• Arteriovenous: Dural arteriovenous fistulae, highly vascularized skull base tumors
• Venous: Idiopathic intracranial hypertension, venous sinus stenosis, high jugular bulb

Structural Causes

• Glomus tumors (most common tumor cause - 16% of cases) 3
• Temporal bone abnormalities
• Dehiscent jugular bulb

Metabolic/Systemic Causes

• High cardiac output states (anemia, thyrotoxicosis, pregnancy)
• Ototoxic medications

Common Pitfalls to Avoid

• Failing to perform appropriate imaging for pulsatile tinnitus (always requires vascular imaging)
• Overlooking idiopathic intracranial hypertension (especially in young, overweight women)
• Missing potentially dangerous vascular causes (arteriovenous fistulae, carotid stenosis)
• Delayed referral for unilateral or persistent pulsatile tinnitus
• Incomplete evaluation of the vascular system

Clinical Pearls

• Pulsatile tinnitus, unlike non-pulsatile tinnitus, usually has an identifiable cause that can be detected with appropriate imaging 3
• The diagnostic approach should be guided by categorizing potential causes as vascular, structural, or metabolic 2
• In cases where initial imaging is negative but symptoms persist, consider conventional angiography for small dural arteriovenous malformations 4
• Compression of the ipsilateral jugular vein during examination can help differentiate between arterial and venous causes