In hearing assessments, if there's a significant difference between air conduction and bone conduction thresholds, what does that indicate?

A significant difference between air conduction and bone conduction thresholds in hearing assessments typically indicates conductive hearing loss. This is because air conduction assessments evaluate the overall ability of the auditory system, while bone conduction bypasses the outer and middle ear, assessing the inner ear and beyond.

When air conduction thresholds are poorer than bone conduction thresholds, it suggests that there is some obstruction or dysfunction in the conductive mechanism of hearing, such as issues with the ear canal, tympanic membrane, or ossicles. This difference is characterized by the fact that sound is transmitted normally through the bone conduction pathway, but impaired through the air conduction pathway.

In contrast, normal hearing would show minimal or no difference between these thresholds, and both types of hearing loss—mixed and sensorineural—would exhibit different patterns without a significant gap, as they involve issues within the inner ear or both the conductive and sensorineural systems.