Name of the Procedure:

Distortion Product Evoked Otoacoustic Emissions (DPOAE); Comprehensive Diagnostic Evaluation (Quantitative Analysis of Outer Hair Cell Function by Cochlear Mapping, Minimum of 12 Frequencies), with Interpretation and Report

Summary

Distortion Product Evoked Otoacoustic Emissions (DPOAE) is a non-invasive hearing test used to assess the function of the outer hair cells in the cochlea. The comprehensive diagnostic evaluation includes quantitative analysis across at least 12 frequencies and includes an interpretation and report.

Purpose

DPOAE tests are primarily used to detect hearing loss, particularly in the high-frequency range. The goals are to:

• Identify any dysfunction in the cochlear outer hair cells.
• Diagnose and monitor conditions affecting hearing.
• Assist in guiding further diagnostic and therapeutic actions.

Indications

• Unexplained hearing loss.
• Tinnitus or ringing in the ears.
• Difficulties in understanding speech, particularly in noisy environments.
• Monitoring of ear health in ototoxic medication use.
• Newborn hearing screening.

Preparation

• No specific fasting or medication adjustments are typically required.
• Patients are advised to avoid exposure to loud noises for at least 24 hours before the test.
• Earwax may need to be removed for accurate results.

Procedure Description

1. The patient is seated comfortably in a soundproof room.
2. A small probe is placed into the ear canal.
3. The probe emits two tones of different frequencies, which evoke a response from the cochlea.
4. The echoes (otoacoustic emissions) generated by the outer hair cells are recorded by the probe.
5. The procedure is repeated for a minimum of 12 different frequencies.
6. Data is collected and analyzed, followed by a comprehensive report.

Duration

The procedure typically takes about 20-30 minutes.

Setting

The procedure is usually performed in an outpatient clinic or an audiologist's office.

Personnel

• Audiologist
• Medical technician (optional)

Risks and Complications

• Extremely low risk.
• Minor discomfort or tickling sensation in the ear canal.
• Rarely, slight irritation of the ear canal.

Benefits

• Early detection and accurate diagnosis of hearing problems.
• Non-invasive and painless with no need for sedation.
• Quick results that can help guide further medical decisions.

Recovery

• No recovery time needed.
• Patients can return to normal activities immediately after the test.
• Follow-up appointments may be needed based on the results.

Alternatives

• Pure tone audiometry: another common hearing test but requires active participation from the patient.
• Auditory Brainstem Response (ABR): more comprehensive, often used when DPOAE results are inconclusive.
• Pros and cons: Pure tone audiometry can miss cochlear outer hair cell dysfunction; ABR is more detailed but also more complex and time-consuming.

Patient Experience

• During the procedure, patients might feel occasional pressure changes or hear soft tones.
• The test is generally comfortable with minimal discomfort.
• Patients are encouraged to stay relaxed and still to ensure accurate results.
• No significant pain is associated with this procedure, and any mild discomfort is typically manageable without special measures.