How do I know when to stop saline injections into expanders?

Hello!  Thank you for your question. You should participate in the final volume as the decision of when to stop expansion should be when you are content with the size in clothing.  You can try your old bras and see how the cup size fits. Often times, your surgeon may slightly overfill the expander to give additional space for the implant.  Your surgeon will then exchange your tissue expander for an accordingly-sized implant.  As the implant is more compressible and natural than the corresponding tissue expander, the appearance may not be as projecting or full as your appearance with the expander. However, shaping of the pocket to create the most aesthetically-appearing breast will likely be performed at that stage.  Hope that this helps. Best wishes!

One of the benefits of having expanders in place is the flexibility they provide. Patients are encouraged to actively participate in the filling process and decisions that need to be made. There are some benchmarks which can be used as guidelines including the capacity of the expander, the weight of the mastectomy resection specimen. It is not uncommon for the surgeon to overfill slightly in order to accommodate the implant at the second stage of reconstruction.Ultimately, the patient should dictate when you are at your goal whether that is before, at, or above capacity.As always, discuss your concerns with your board certified plastic surgeon.

This is something that you should be discussing with your surgeon.  In general the permanent implants are more compressible and look smaller than tissue expanders of similar size. Most surgeons will slightly overfill the expanders and stretch the skin prior to implant placement so it is not so tight around the implant.  It is also helpful to give the stretched skin time to expand and relax for several months prior to implant placement.