What test is being performed when a tuning fork is placed on the forehead to assess hearing loss?

Weber Test Identification in Hearing Loss Assessment

The nurse practitioner is performing the Weber test, which is used to differentiate between conductive hearing loss and sensorineural hearing loss. 1

Understanding the Weber Test

The Weber test is a simple bedside hearing assessment that involves:

1. Vibrating a tuning fork (typically 256 or 512 Hz) by striking it on a protected surface like a covered elbow or knee
2. Placing the handle of the vibrating tuning fork at the midline of the forehead or on maxillary teeth
3. Asking the patient where they hear the sound 1

Interpretation of Weber Test Results

• Normal finding: Sound is heard at midline or "everywhere"
• Lateralization to one ear: Indicates either:
  • Conductive hearing loss (CHL) in the ear where sound is heard better, OR
  • Sensorineural hearing loss (SNHL) in the opposite ear 1

Clinical Significance of the Weber Test Result

In this case, the sound lateralizing to the left ear suggests either:

• Conductive hearing loss in the left ear, OR
• Sensorineural hearing loss in the right ear 1

Complementary Testing

The Weber test should be performed alongside the Rinne test for more complete assessment:

• Rinne test: Compares air conduction to bone conduction by:
  1. Placing the tuning fork on the mastoid bone
  2. Moving it to the entrance of the ear canal
  3. Asking which position produces louder sound 1

Clinical Application

The Weber and Rinne tests together help clinicians:

• Distinguish between conductive and sensorineural hearing loss
• Make preliminary diagnoses prior to formal audiometric testing
• Guide appropriate referrals and treatment plans 1

Important Considerations

• Tuning fork tests provide reasonable initial information but do not replace formal audiometric testing 1
• Proper technique is crucial - the tuning fork should be struck correctly to avoid nonharmonic frequencies 1
• In older adults, age-related sensorineural hearing loss (presbycusis) is the most common type of hearing loss 2
• Lateralization patterns may be affected by longstanding unilateral hearing loss due to central adaptation processes 3

Common Pitfalls to Avoid

• Failing to remove cerumen impaction before assessment, which can cause conductive hearing loss 1, 4
• Not considering that patients with sudden sensorineural hearing loss often report tinnitus, ear fullness, and vertigo 1
• Overlooking that the accuracy of tuning fork tests may be lower in children 5

By performing the Weber test correctly, the nurse practitioner is taking an important first step in determining the type and laterality of hearing loss, which will guide further diagnostic testing and management.