Evaluation and Management of Unilateral Pulsatile Tinnitus Lasting 9 Months
This patient requires urgent imaging evaluation with high-resolution CT temporal bone or CT angiography of the head and neck, as pulsatile tinnitus lasting 9 months in one ear has an identifiable—and potentially life-threatening—vascular or structural cause in over 70% of cases. 1, 2
Why Imaging Cannot Be Delayed
Your patient's presentation has moved well beyond "transient" pulsatile tinnitus (which refers to episodes lasting only minutes) and represents persistent, unilateral pulsatile tinnitus requiring comprehensive workup 3. The 9-month duration and unilateral nature significantly elevate the likelihood of an identifiable structural or vascular cause 2.
Critical life-threatening causes that must be ruled out include: 2
- Dural arteriovenous fistula (8% of cases)—can present with isolated pulsatile tinnitus before catastrophic hemorrhage or stroke
- Arterial dissection—requires urgent identification
- Atherosclerotic carotid artery disease (17.5% of cases)—most common arterial cause
Initial Clinical Assessment Before Imaging
Perform targeted otoscopic examination specifically looking for: 1, 2
- Vascular retrotympanic mass (suggests paraganglioma/glomus tumor—16% of cases)
- This finding changes your imaging strategy
Assess for objective versus subjective tinnitus: 1, 2
- Can you hear the pulsatile sound with a stethoscope over the ear, mastoid, or neck?
- Objective tinnitus (audible to examiner) is rare but strongly suggests vascular pathology requiring immediate workup
Check for compression maneuvers: 2
- Does carotid or jugular compression relieve the tinnitus?
- Relief suggests venous etiology (sigmoid sinus abnormalities, jugular bulb variants) or arterial dissection
Screen for red flags requiring immediate escalation: 4
- Focal neurological deficits
- Asymmetric or unilateral hearing loss (obtain audiometry)
- Severe headaches (suggests intracranial hypertension—second most common cause at ~20% of cases) 2
First-Line Imaging Strategy
Choose between two equally appropriate first-line options based on clinical suspicion: 2
Option 1: High-Resolution CT Temporal Bone (Non-Contrast)
Order this if you suspect: 1, 2
- Paragangliomas or glomus tumors (especially if vascular retrotympanic mass seen)
- Jugular bulb abnormalities (high-riding jugular bulb, dehiscence of sigmoid plate)
- Superior semicircular canal dehiscence
- Aberrant vascular anatomy (persistent petrosquamosal sinus, abnormal emissary veins)
- Adenomatous middle ear tumors
Option 2: CT Angiography (CTA) of Head and Neck with Contrast
Order this if you suspect: 1, 2
- Dural arteriovenous fistulas (life-threatening if missed)
- Arterial dissection (life-threatening if missed)
- Atherosclerotic carotid artery disease (most common cause overall)
- Sigmoid sinus diverticulum or dehiscence (commonly associated with intracranial hypertension)
- Arteriovenous malformations
Practical note: CTA source images can be reconstructed to create dedicated temporal bone CT images without additional radiation exposure, making CTA a reasonable "one-stop-shop" initial study 2.
When to Proceed to Advanced Imaging
Order MRI with contrast and MR angiography if: 2
- CT/CTA are negative but clinical suspicion remains high
- Suspected cerebellopontine angle lesions or acoustic neuroma
- Vascular malformations not identified on CT/CTA
- Patient has contraindications to iodinated contrast
Consider digital subtraction angiography (DSA) if: 5
- Initial vascular imaging is negative but vascular etiology is strongly suspected
- This is the gold standard for detecting subtle dural arteriovenous fistulas
Common Pitfalls to Avoid
Do not dismiss this as benign: 2
- Pulsatile tinnitus almost always requires imaging evaluation due to identifiable causes in >70% of cases
- Missing dural AVF can result in catastrophic hemorrhage before other symptoms develop
Do not order imaging for the wrong indication: 1
- If asymmetric hearing loss is present, follow ACR criteria for hearing loss rather than tinnitus protocols
- If neurologic deficits are present, follow cerebrovascular disease protocols
Do not perform inadequate otoscopic examination: 2
- Missing a vascular retrotympanic mass (paraganglioma) leads to delayed diagnosis and inappropriate imaging selection
Do not overlook intracranial hypertension: 2
- Particularly in young, overweight women with headaches
- Can lead to vision loss if missed (idiopathic intracranial hypertension/pseudotumor cerebri)
Referral and Concurrent Management
Refer to otolaryngology for: 3
- Comprehensive evaluation and audiologic testing
- Coordination of imaging interpretation and treatment planning
Screen for psychiatric comorbidity: 1
- Patients with tinnitus and severe anxiety or depression require prompt identification and intervention
- Suicide is reported in tinnitus patients with co-existing psychiatric illness