Acute perilymphatic fistulae caused by nonpenetrating trauma or idiopathic etiologies should be first managed conservatively with bed rest and avoidance of any increase in intracranial pressure. If symptoms do not improve, or even worsen during this time, surgical exploration should be considered.

Once the decision has been made to explore the middle ear for a perilymph fistula, a routine should be followed to minimize the possibility for inaccurate diagnosis. Injection of topical anesthetics should be kept to a minimum to avoid pooling of anesthetic fluids in the window niches. Once the tympanomeatal flap has been raised, the round window niche should be gently suctioned and briefly examined. The entire oval window niche must be visualized, which usually requires curettage of the scutum. Using microsuction and high-power magnification, both the oval and round windows should be inspected with the patient in the Trendelenburg position, while the anesthetist performs a Valsalva maneuver. Gentle manipulation of the ossicular chain should also be done while visualizing both window niches. If the stapedial footplate is fractured, a total stapedectomy should be performed. More commonly, the perilymph leak is around the annular ligament of the footplate or in the round window niche. In such cases, the mucosa around the windows should be escarified with a micropick and a piece of soft tissue placed over the region. In the round window niche, a plug of fibrofatty tissue works well to obliterate the niche and directly contact the round window membrane. The oval window niche is best managed by using a thin piece of perichondrium cut in a pants-leg fashion, to cover the annular ligament of the footplate completely, overlapping only at the posterior margin of the footplate. This type of repair is performed, even if no perilymph leak has been identified at surgery. It is my philosophy that if I have entertained this diagnosis so seriously that I have advised the patient to undergo an operative procedure, I seal both windows in the event that this is an intermittent fistula.

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