If used correctly, hyaluronidase can dissolve persistent deposits of hyaluronic acid fillers, such as Restylane, Perlane, Juvederm, etc.
The key, of course, is using just a touch of the hyaluronidase. If used very sparingly, yes, it is possible to dissolve just the lump while leaving the majority of the Restylane intact.
We do a tremendous amount of fillers in my office, especially in the tear trough or lower eyelid area. We also see many patients coming in for revision of prior incorrectly performed injections. Usually, I am able to correct just the problem area, without needing to reinject filler. Sometimes, however, the surrounding filler also melts away, so a small touch up may be necessary, and I always warn patients of this reality before we start.