A fistula test with pressure on the left ear canal increased the intensity of the nystagmus, so an explorative tympanotomy (ET) was performed a day later under general anesthesia due to a suspected PLF.
Fistula test showed positive results in one patient  and negative in another .
These represent very unspecific findings; furthermore, fistula test is a very specific but poorly sensitive diagnostic tool.
The fistula test (FT) is a bedside vestibular method of examination that detects the existence of an abnormal communication between the middle and inner ear.
The purpose of this case series is to demonstrate a specific methodology for the evaluation of the inner ear in cases with a false negative fistula test in patients with chronic ear disease with cholesteatoma.
The fistula test was negative and in the vHIT only the gain for head impulses towards the affected side in the plane of the horizontal semicircular canal was abnormal.
In this report, we have demonstrated three patients with radiologically and surgically confirmed horizontal semicircular canal fistula but with a false negative fistula test. Bedside head impulse testing was able to show the abnormal vestibule-ocular reflex and in one case was able to localize the deterioration to a particular semicircular canal.
(3,4) Vartiainen et al found that a positive vestibular fistula test
was even more often negative than positive in patients with a surgically demonstrated fistula.
A fistula test in the right ear was positive, with both a mild right-beating nystagmus and a sensation of vertigo.
(2) Over the years, the most frequently studied physical examination finding has been the fistula test for Hennebert's sign.
(2) An ENG fistula test may be useful as a supplement to the clinical fistula test.
Findings on the Hallpike maneuver, the fistula test
, and examination of the sinus, pharynx, and neck were also normal.