PLF involves damage to the membranes between the middle and inner ear. The membranes can have a tear, there can be a hole or they can be too slack. PLF can result from severe pressure changes, from inside or outside the body, or a trauma – a car crash for instance. The trauma doesn’t necessarily have to have occurred to the head. Perilymph Fistula can usually heal by itself, if the patient follows certain precautions. If there is a hole in the temporal bone as well (SCDS), however, the fistula will not heal permanently, particularly if the dehiscence is large. If the bone is thin but a hole hasn’t formed, rather than proceeding straight to surgery, the patient can consider trying conservative methods ie. non-surgical options. They include prevention of anything that will cause a rise in intracranial pressure: avoidance of straining and bending over, a low salt diet, avoidance of pressure altering situations (air travel, scuba), a trial of diuretics to lower intracranial pressure.
The perilymph fistula surgery is known by different names: a fistula repair, or round window occlusion. A strict postoperative regime needs to be followed to stand any chance of such an operation being successful. Be aware, some doctors may tell a patient that PLF is a controversial diagnosis. When it comes to the inner ear it seems nothing is written in stone. Other doctors, with considerable experience treating SCDS patients, take the view that SCDS treatment will only be successful if one proceeds from the hypothesis that PLF does exist.
Here you may read about a balance test for perilymph fistula.