False positive fistula test: Here the test is positive inspite of absence of fistula:
- Congenital syphilis- here stapes footplate is hypermobile.
- Meniere’s disease (Hennebert’s sign)- It is due to the fibrous bands connecting utricular macula to the stapes footplate.
- Hypermobile stapes footplate.
False negative fistula test: Inspite of fistula being present the test is negative or normal in cases of:
- Cholesteatoma covering the fistula- does not allow pressure changes to be transmitted to the labyrinth.
- Dead labyrinth.