Sudden Hearing Loss Workup

Updated: Dec 28, 2021
  • Author: Neeraj N Mathur, MBBS, MS, DNB, MAMS, FAMS; Chief Editor: Arlen D Meyers, MD, MBA  more...
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Laboratory Studies

Routine, nontargeted laboratory testing is not recommended. [1] Laboratory studies should be directed by the history and physical examination findings and can include the following:

  • Fluorescent treponemal antibody absorption (FTA-Abs) for syphilis

  • Antinuclear antibodies (ANA), rheumatoid factor, and erythrocyte sedimentation rate (ESR), for autoimmune diseases

  • International normalized radio (INR), activated partial thromboplastin time (aPTT), and clotting time, for coagulopathy

  • CBC and differential, for infection

  • Thyroid-stimulating hormone (TSH) for thyroid disease

  • Fasting blood glucose for diabetes mellitus

  • Cholesterol and triglycerides, for hyperlipidemia


Imaging Studies

Approximately 1-2% of patients with ISSHL have internal auditory canal (IAC) or CPA tumors. Conversely, 3-12% of patients with vestibular schwannomas present with sudden hearing loss.

Magnetic resonance imaging (MRI) with gadolinium diethylenetriamine-pentaacetic acid (DPTA) enhancement is the criterion standard test for diagnosing CPA masses, especially because a 30-40% false-negative rate exists with auditory brainstem response (if hearing levels permit). The cost issue for MRI has been addressed by performing limited studies using fast spin echo techniques.

According to 2012 guidelines from the American Academy of Otolaryngology-Head and Neck Surgery Foundation (AAO-HNSF), computed tomography (CT) scans are not helpful and expose the patient to ionizing radiation. Therefore, CT scans are not recommended in the initial evaluation of patients with presumptive SSNHL. [1] However, in young patients, for whom only a small possibility of detecting a vestibular schwannoma exists, a noncontrast temporal bone CT scan could be obtained. Anatomic defects such as a Mondini dysplasia or enlarged vestibular aqueduct might account for a sudden hearing loss.


Other Tests

See the list below:

  • Audiometry, including pure-tone and speech tests and immittance (tympanometry and acoustic reflex) tests, is mandatory. Testing can be directed by information gleaned from the history and physical examination. Obtaining those laboratory tests for which the results may influence the treatment plan is wise.

  • Auditory brainstem response testing and otoacoustic emissions (OAE) tests may provide additional information regarding the functional integrity of the auditory system.

    • OAE testing can provide information about cochlear function, and the auditory brainstem response can be used to assess auditory nerve function.

    • The auditory brainstem response and OAE results may also assist in diagnosing a functional hearing loss.

  • Vestibular tests are not mandatory and are obtained when indicated by the history and physical examination findings.