How the two tuning fork tests work
The Weber test places a vibrating tuning fork on the middle of the forehead or the top of the head, and the client says where the sound is louder. In normal hearing it is heard equally. The Rinne test compares air conduction (fork near the ear canal) with bone conduction (fork on the mastoid bone) in each ear. Normally air conduction is heard longer than bone conduction, which is called a positive Rinne.
Conductive versus sensorineural patterns
In conductive loss, sound cannot travel well through the outer or middle ear. Bone conduction bypasses the blockage, so on the Rinne test bone conduction is longer than air in the affected ear, and on the Weber test the sound lateralizes to the affected ear, because that ear is not masked by room noise. In sensorineural loss, the inner ear or nerve is damaged, so both air and bone conduction are reduced but air stays longer, and the Weber sound lateralizes to the better ear.
| Pattern | Weber | Rinne in affected ear |
|---|
| Conductive loss | Louder in the affected ear | Bone longer than air |
| Sensorineural loss | Louder in the better ear | Air longer than bone (both reduced) |
| Normal hearing | Equal in both ears | Air longer than bone |
Putting his results together
His Weber sound is louder in the right ear. On its own, that could mean right conductive loss or left sensorineural loss. The right Rinne result settles it: bone conduction is longer than air on the right, which is the signature of conductive loss in the right ear. The left Rinne is normal, with air longer than bone, so the left ear has no conductive loss. Left sensorineural loss would send the Weber sound to the right, but it would not explain the abnormal right Rinne. Right sensorineural loss would send the Weber sound to the left.
Clinical relevance
Common causes of conductive loss include impacted cerumen, middle ear fluid or infection, and otosclerosis. In an older adult, cerumen is frequent and easily treated. The finding does not exclude coexisting age-related sensorineural loss; it means that the right ear has a conductive component that should be evaluated. Accurate baseline hearing information is also important because he is starting an ototoxic drug.
Exam takeaway
Key point Conductive: Weber to the bad ear, bone longer than air. Sensorineural: Weber to the good ear, air longer than bone. Use the Rinne result to decide which ear is affected.