The majority of proteins were found to be present in perilymph at levels reflecting the total protein gradient between perilymph and plasma. With the possible exception of presumed perilymphatic fistula, it is not envisioned that the analysis of perilymph will be used for diagnostic purposes but rather as a tool for the elucidation of the mechanisms underlying inner ear disease, whether localized or as part of systemic alteration. The diagnosis of perilymph fistula remains a most controversial and challenging topic in otology. Perilymph fistula is an abnormal communication between the middle ear and the perilymphatic space. The major problem with the diagnosis and treatment of perilymph fistula that to date no reliable pre- and intraoperative diagnostic tests exist.
Diagnosis is based upon history, and physical examination.
No consensus as to management exists as a restul of this. A search for a specific marker to identify the fluid encountered in the middle ear upon exploratory surgery in patients with suspected perilymph fistula ensued. The establishment of protein maps of inner ear fluids and the revelation of a specific protein and of several examples of proteins showing striking differences in concentration when compared with other body fluids seemed most promising. Proteins significantly different between plasma and perilymph, and therefore relevant to perilymph fistula, are boxed. Beta-2 transferrin We confirmed earlier findings that this protein was present in perilymph and CSF, but absent in normal plasma.