Can a doctor use same pocket when using larger implants?

More information is needed.  Are you under the muscle?  Are your current implants soft?  Are your pockets OK now?  Do you have too much lateral displace or too wide cleavage?  Can you post photos?If you have a current submuscular pocket that is acceptable in shape and look, then your surgeon will likely just fine tune your current pocket to allow for a larger implant.Bottoming out coming from overaggrssive release of the muscle and/or a patient with very soft/weak connective tissue.

Absolutely. The same pocket can be used. Modifications may need to be made to the pocket depending on the size of the pocket in relationship to the size of the implant. When going bigger, the pocket may need to be opened up a bit. That would be decided by your surgeon either ahead of time or in the operating room.