Slow valve leak? (Photo)

Thank you for your question.   If there is a visible size difference that you can see which was not present before your accident that a leak of the left saline implant is a possibility.  Please see your plastic surgeon for an examination As an exam can often tell if the left implant has deflated.  Replacement of the implant would be indicated if it has.

Hello, I can't offer an opinion whether your implant might have leaked based on the photo.  I think that your plastic surgeon will be the best source of information regarding this issue.

Hi, HoneyM.  Valve leaks in saline implants do occur, but are not common and may be hard to diagnose as the saline leakage is often small and sporadic.  It is most commonly thought that a valve leak occurs with a minor defect in the valve (either from manufacture or occurring intra-operatively) or from tissue ingrowth into the valve.  It is conceivable that high-force trauma, such a motor vehicle accident and seatbelt force, could cause some friction trauma or pull to an implant valve (especially if there is scar tissue in the immediate area).
In my experience, subtle asymmetry following a car accident is usually a result of alteration of the implant pocket due to the forces occurring from the accident.  Scar tissue, as well as the breast's natural borders and creases can be disrupted from the shear forces that occur.  Increased expansion of the implant pocket may cause the implant to sit in a different position and/or orientation, changing the appearance of the breast as well its perceived volume.  The fact that you now have a double crease along the bottom of your breast would make me suspicious that this is what has occurred.
Time will help sort out the cause of your post-accident changes, along with close follow-up with your surgeon.  Good luck!