Labyrinthine fistula, bilateral

This code signifies the presence of an abnormal connection or opening between the inner ear (labyrinth) and another structure, affecting both ears. This defect can lead to perilymph leakage, causing symptoms such as vertigo, hearing loss, and nystagmus.

Apply this code when documentation explicitly states a labyrinthine fistula is present bilaterally. This diagnosis is often made following imaging studies (e.g., CT scan) or surgical exploration, confirming the communication between the labyrinth and the middle ear or mastoid.

• Ensure documentation specifies "bilateral" involvement; otherwise, use a unilateral or unspecified code.
• Look for associated symptoms like conductive or sensorineural hearing loss (H90.-) or vertigo (R42) which may require additional coding.
• Distinguish from other inner ear disorders like Ménière's disease (H81.0-) or benign paroxysmal positional vertigo (H81.1-) unless a fistula is also present.