Air–Bone Gap
Also written as: ABG — Air–Bone Gap
The difference in decibels between a patient's air-conduction and bone-conduction thresholds at the same frequency, indicating the presence and degree of a conductive component to hearing loss.
Full Definition
An air–bone gap (ABG) is present when bone-conduction thresholds are significantly better (lower dB HL) than air-conduction thresholds at the same frequency, typically considered significant at ≥10 dB HL. It is the primary audiometric indicator of conductive hearing loss. The dash in 'air–bone' should be an en dash (–), not a hyphen (-) or em dash (—), as it separates two coordinate nouns. Editors should confirm correct dash usage and ensure the gap is expressed in consistent units throughout a document.
Usage
Usage note: Use an en dash between 'air' and 'bone' in 'air–bone gap'. Confirm that both AC and BC threshold data are available before the ABG is reported.
In Context
- "An air–bone gap of 30 dB HL at 500 Hz was identified, confirming a moderate conductive hearing loss." — Audiological assessment report
- "The draft used a hyphen in 'air-bone gap'; this was corrected to an en dash per standard audiological style." — Copy-editing note