Can a brain tumor cause constant or intermittent pulsatile tinnitus?

Can a Brain Tumor Cause Pulsatile Tinnitus?

Brain tumors, specifically highly vascularized skull base tumors like paragangliomas and glomus tumors, are a well-established cause of pulsatile tinnitus, accounting for 16% of cases, and can present with either constant or intermittent symptoms. 1

Understanding the Mechanism

Brain tumors cause pulsatile tinnitus through two primary mechanisms:

• Highly vascularized tumors (paragangliomas, glomus tympanicum/jugulare, adenomatous middle ear tumors) create turbulent blood flow that generates audible pulsations synchronous with the heartbeat 1, 2
• Mass effect from intracranial tumors can elevate intracranial pressure, leading to venous sinus abnormalities that produce pulsatile tinnitus 3

The pulsatile nature can be constant or intermittent depending on patient positioning, blood pressure fluctuations, and the degree of vascular involvement 4, 2

Critical Diagnostic Considerations

When to Suspect a Tumor

• Unilateral pulsatile tinnitus has higher likelihood of identifiable structural cause including tumors compared to bilateral presentation 1
• Visible vascular retrotympanic mass on otoscopy strongly suggests paraganglioma or glomus tumor 1
• Objective pulsatile tinnitus (audible to examiner) is rare but strongly suggests vascular pathology including highly vascularized tumors 1

Imaging Strategy

First-line imaging should be high-resolution CT temporal bone (non-contrast) when paragangliomas, glomus tumors, or adenomatous middle ear tumors are suspected, as these are best visualized on bone algorithm CT studies 5, 1, 6

• CT temporal bone identifies skull base tumors, bony erosion patterns characteristic of paragangliomas, and jugular bulb abnormalities 1, 4
• MRI with contrast and MRA should be reserved for cerebellopontine angle lesions (vestibular schwannoma, acoustic neuroma) or when CT/CTA are negative but clinical suspicion remains high 5, 1

Other Important Causes to Consider

While evaluating for brain tumors, recognize that pulsatile tinnitus has identifiable causes in >70% of cases 1, 7:

• Atherosclerotic carotid artery disease is the most frequent cause (17.5% of cases) 1
• Idiopathic intracranial hypertension is the second most common cause, particularly in young overweight women 1
• Dural arteriovenous fistulas (8% of cases) are life-threatening and can cause hemorrhagic or ischemic stroke if untreated 1, 7

Critical Pitfalls to Avoid

• Never dismiss pulsatile tinnitus as benign—it almost always requires imaging evaluation due to identifiable causes in >70% of cases 1
• Missing dural AVF is life-threatening, as it can present with isolated pulsatile tinnitus before catastrophic hemorrhage 1
• Inadequate otoscopic examination can delay diagnosis of vascular retrotympanic masses (paragangliomas) and lead to inappropriate imaging selection 1
• Overlooking intracranial hypertension in young overweight women with headaches can lead to vision loss 1

Treatment Implications

• Paragangliomas and glomus tumors can be treated with surgical resection, radiation therapy, or observation depending on size and symptoms 1
• The specific treatment approach depends on tumor location, size, patient age, and symptom severity 1