The mechanical trauma induced by the injection of saline into an area of prior filler treatment may actually hasten the natural process of dissolution and removal that ordinarily is responsible for its breakdown and removal. I have in fact successfully used saline injections in patients who have come to me complaining of undesirable results that they had obtained elsewhere with the use of a calcium-based volumizing filler, Radiesse. In this case, both the mechanical action of needles and the saline itself are believed responsible for hastening the dissolution of the filler. The same can reasonably be asserted when considering the use of saline injections in a region of prior hyaluronic acid-based filler injection. I am curious, however, to know the actual reason that saline is being used in your case. Is it perhaps to enhance subcision with the needle?