How many CC's do you lose when going under the muscle?

There is an imperceptible loss of projection
approximately 1 cm and volume following subpectoral breast augmentation. This would clearly depend on the thickness of
the pectoral muscle

No one will be able to predict your cup size, because there is no standard bra sizing among different manufacturers.  You should re-visit with your surgeon to look at before and after photos of patients who look like you, try on sizers, do the "rice test,"  and avail yourself of all options to know what it may look like to have 500 or 550 ccs.  Your surgeon will be the best guide, so go back one more time for final questions. Click on the link below to see a breast augmentation that is fully healed. 

It's not volume, or cc's, that you lose when you put your implants under the muscle, it's that what you are trying on on top of your breasts will lose some projection once the implant is under the muscle.  The volume is still there.  This is why it is important to do a sizing exercise properly and to have a consultation with an experienced board certified plastic surgeon who has the proper types of sizers and the expertise to guide you in making the right choices.  In my experience, when done properly the sizing exercise with specially designed volumetric sizers does an excellent job of accurately demonstrating postop appearance.  With this method, we have very few, if any, cases in which we have to return to the OR to exchange sizes  Good luck.

 Thank you for the question. In my opinion, it is not possible to accurately determine how many CCs the you would “lose” when undergoing sub muscular breast augmentation surgery.  I would suggest that you do not make your decisions based on statement such as: “you will lose 50 cc of volume when breast implants are placed under the muscle”. These statements are simply not reliable enough to utilize clinically. Generally speaking, the best online advice I can give to ladies who are considering  breast augmentation surgery (regarding breast implant size/profile selection) is:
1. Concentrate on choosing your plastic surgeon carefully.  Concentrate on appropriate training, certification, and the ability of the plastic surgeon to achieve the results you are looking for. Ask to see lots of examples of his/her work. Sometimes, it is necessary to seek several consultations before you feel comfortable about your choice.
2. Have a full discussion and communication regarding your desired goals  with your plastic surgeon. This communication will be critical in determining  breast implant size/type/profile will most likely help achieve your goals. 
In my practice, the use of photographs of “goal” pictures (and breasts that are too big or too small) is very helpful. I have found that the use of words such as  “natural” or "large C or small D cup” etc means different things to different people and therefore prove unhelpful.
 Also, as you know, cup size varies depending on him who makes the bra; therefore, discussing desired cup  size may also be inaccurate. Again, best not to discuss your goals and/or judge the outcome of the procedure performed based on achieving a specific cup size.  The use of computer imaging may be very helpful during the communication process. The use of  in bra sizers may also be helpful. In other words, use as many “visual aids” as possible during the communication process. I encourage patients to meet  with me as my times as necessary, to feel comfortable that we are both on the “same page”.
 
3.  Once you feel you have communicated your goals clearly,  allow your plastic surgeon to use his/her years of experience/judgment to choose the breast implant size/profile that will best meet your goals.  Again, in my practice, this decision is usually made during surgery. I generally select appropriate breast implant size/profile after the use of temporary intraoperative sizers and viewing the patient's chest in the upright and supine positions.
I hope this (and the attached link,  dedicated to breast augmentation surgery concerns) helps.  Best wishes.

Like fitting a shoe to your foot or a dress to your body, you aren't really looking for a size number, you're looking for what fits or what gets the effect you're looking for. There is no loss of actual volume because the implant is below the pectoralis muscle. The difference is in effect of the same volume. Implants are placed behind the pectoralis muscle for the upper half of the breast because they are better padded and protected and look more natural. The apparent size increase of smooth, round implants placed behind the pectoralis muscle is from one to two cup sizes compared to what you start from unless your breast is unusually wide or narrow for your chest. It is not wise to just choose a number of cc's and expect a certain result or choose a result and expect it to be just done. I would also disagree with responses recommending using external sizers to judge this. Implants are properly sized by their diameter compared to the space behind the breast they are to fill and a choice of forward volumes (profiles) for the effect of 1-2 cup sizes of increase. Based on my experience, choosing an overly large implant volume like 550 cc's and forcing it to work is looking for an unnatural result and distortions that may require a revision to fix. 

Your best bet when you are trying to decide on implants is to try on sizers of the exact implant you are considering inside a very tight sports bra. This will give you a close idea of what you will look like. More importantly the dimensions or width of the implants need to match and fit your frame and body. If you are working with a board certified plastic surgeon with an expertise in breast augmentation he or she should be able to help you with this in their office. Good luck! best, Dean Vistnes, M.D

AAjoslin,      At your height and weight, with scant tissues, those are going to be pretty large implants, and will likely appear relatively round.  The issue here is not loss of volume, but compression of the silicone gel, which lessens the projection of submuscular implants a little.  Also, the same implant over the muscle (which I would not advocate), would appear narrower, and thus more projecting, because the submuscular positioning makes the base appear wider, and thus the width to projection ratio is different, with the same volume.  Saline under the muscle does not compress quite as much, either.  I hope that this help.  Good Luck.Best wishes,Tom DeWire, MD, FACS     Richmond, VA