A 36 year old man shows positive Rinne test. His condition is:
**Question:** A 36 year old man shows positive Rinne test. His condition is:
A. Sensorineural hearing loss
B. Conductive hearing loss
C. Vestibular disorder
D. Unknown cause of hearing loss
**Correct Answer:** **B. Conductive hearing loss**
**Core Concept:**
The Rinne test is a clinical audiologic test used to differentiate between conductive and sensorineural hearing loss. The test involves measuring the air conduction and bone conduction thresholds of a specific frequency. A positive Rinne test result indicates that the air conduction threshold is lower than the bone conduction threshold, suggesting a conductive hearing loss.
**Why the Correct Answer is Right:**
In a conductive hearing loss, sound waves are unable to travel efficiently through the outer ear, ear canal, or middle ear structures (e.g., due to ear infections, cerumen (wax) blockage, or eardrum perforation). When measuring the air conduction threshold, the auditory nerve is bypassed, as sound waves travel via the air. By comparing the air conduction threshold with the bone conduction threshold, a positive Rinne test indicates that the air conduction threshold is lower than the bone conduction threshold, supporting the diagnosis of conductive hearing loss.
**Why Each Wrong Option is Incorrect:**
A. Sensorineural hearing loss (choice A) is caused by abnormalities within the inner ear or auditory nerve, resulting in a negative Rinne test (air conduction threshold higher than bone conduction threshold).
C. Vestibular disorders (choice C) typically present with vertigo, dizziness, and imbalance, not a Rinne test result.
D. The cause of hearing loss (choice D) is unknown after the Rinne test is performed, but the test helps narrow down the potential causes.
**Clinical Pearl:**
The Rinne test is a simple, non-invasive tool to help differentiate between conductive and sensorineural hearing loss. It should be performed in conjunction with the Weber test, which involves assessing sound localization, as both tests together provide valuable information for diagnosing the cause of hearing loss.