What imaging modalities are used to diagnose tinnitus (ringing in the ears)?

From the Guidelines

Imaging is not typically used as a primary diagnostic tool for tinnitus, but MRI of the brain with contrast is the preferred imaging modality when tinnitus is unilateral, pulsatile, associated with hearing loss, or accompanied by neurological symptoms, as recommended by the most recent guidelines 1.

Key Points to Consider

• Tinnitus is a subjective symptom that cannot be directly visualized, and imaging studies are not always necessary for diagnosis.
• The American College of Radiology (ACR) guidelines suggest that imaging studies should only be performed when there are concerning features suggesting an underlying structural cause, such as unilateral tinnitus, pulsatile tinnitus, or asymmetric hearing loss 1.
• MRI of the brain with contrast is the preferred imaging modality for evaluating tinnitus, particularly when it is unilateral, pulsatile, or associated with hearing loss or neurological symptoms.
• CT scans may be used when bony abnormalities are suspected, and CT or MR angiography may be appropriate for evaluating vascular causes of pulsatile tinnitus 1.
• Imaging studies should be part of a comprehensive evaluation that includes a thorough history, physical examination, and audiological testing to properly assess and manage tinnitus.

Important Considerations for Imaging

• The ACR guidelines recommend against imaging studies for patients with symmetric or bilateral, subjective, nonpulsatile tinnitus in the absence of other symptoms 1.
• Imaging studies may not be necessary for patients with tinnitus that does not localize to one ear, is nonpulsatile, and is not associated with focal neurological abnormalities or asymmetric hearing loss 1.
• The choice of imaging modality depends on the type of tinnitus and associated symptoms, and should be guided by the ACR Appropriateness Criteria topics for "Hearing Loss and/or Vertigo", "Head Trauma", and "Cerebrovascular Diseases-Aneurysm, Vascular Malformation, and Subarachnoid Hemorrhage" 1.

From the Research

Imaging Modalities for Diagnosing Tinnitus

The following imaging modalities are used to diagnose tinnitus:

• MRI (Magnetic Resonance Imaging): used to rule out retrocochlear disease in patients with unilateral, non-pulsatile tinnitus 2
• CT (Computed Tomography): used as the initial imaging strategy for pulsatile tinnitus in certain clinical features, such as retrotympanic mass or conductive hearing loss 2
• Temporal bone CT: used to investigate pulsatile tinnitus 2
• Arterial and venous imaging: used to investigate pulsatile tinnitus 2
• Conventional angiography: rarely indicated, but may be used to exclude significant pathology such as dural arteriovenous malformation 2

Indications for Imaging

Imaging is indicated in the following cases:

• Unilateral or asymmetric tinnitus 3, 4, 2
• Tinnitus associated with focal neurologic abnormalities or asymmetric hearing loss 3, 4, 2
• Pulsatile tinnitus 2
• Objective pulsatile tinnitus, to exclude significant pathology such as dural arteriovenous malformation 2

Diagnostic Approach

The diagnostic approach to tinnitus involves:

• Comprehensive history and physical examination 3, 4, 5
• Audiologic evaluation 3, 4, 5
• Blood profile analysis 5
• Referral to a specialist when necessary 5
• Imaging studies, as indicated by the clinical assessment 2