I think this point is quite important in that I have seen many cases, both clinically as well as forensically, where patients are labeled as brain injured when they in fact only have a vestibular disorder causing an array of somatic, cognitive and behavioral symptoms that were incorrectly apportioned to brain injury. The diagnoses of traumatic brain injury and perilymphatic fistula are not mutually exclusive and must be treated for each accordingly. The definitive diagnostic test for perilymphatic fistulas remained somewhat controversial. There has been recent literature looking at the use of the fistula test that questions its utility as a definitive measure of PLF presence. Hennebert's test, among others.
Many clinicians believe that the definitive diagnosis can only be made at the time of surgery.
Based on the inspection, however, many clinicians will tell you even at that point that it is still difficult at times to make a definitive diagnosis. Newer techniques utilizing analysis of fluid harvested at the time of surgical inspection with analysis for beta II transferring via immunoblotting assay have been used to assist in definitively making the diagnosis. This substance is only found in cerebral spinal fluid and inner ear perilymph and is absent from serum and other body fluids. Generally, post traumatic PLF heal spontaneously. Treatment of non-resolving OPLF involved surgical patching of the leak if bed rest is ineffective.