Can I go from a B cup to a C cup with 350cc or 375cc saline implants under the muscle? (photo)

Unfortunately,
you have not told us your bra size just your cup size. If you are a 32 or 34 each 100 cc’s of
implant corresponds to 1 cup size change.
If you are a 36 or 38 each 200 cc’s of implant corresponds to 1 cup size
change. From this, you can compute the
volume required to achieve your desired goal.
However, more important than the implant would be a lift. There is a new technique called Breast
Augmentation with Mini Ultimate Breast LiftTM. Using only a circumareola incision it is
possible to reshape your breast tissue creating upper pole fullness, elevate
them higher on the chest wall and more medial to increase your cleavage. Through the same incision, implants can be
placed. Aligning the areola, breast
tissue and implant over the bony prominence of the chest wall maximizes
anterior projection with a minimal size implant. Small round textured silicone gel implants
placed retro-pectoral look and feel more natural, are more stable, less likely
to ripple or have complications needing revision. Best Wishes,Gary Horndeski, M.D.

Dear Katherine,
Based on your description and picture you are a good candidate for a breast lift and augmentation with Implants. The sizes you mentioned will likely provide you with a good result, however, you would need to be examined in person and preferably have 3-D Vectra imaging and morphing to show you what you would look like with different type breast lifts as well as size size, diameter and shape implants.

I would agree with your plastic surgeon that a breast lift will be helpful in your case. Exactly what type of breast lift I would recommend to you would be based on physical examination.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.
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 “B cup, small C 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.
 The use of computer imaging technology may also be very helpful during this communication process.

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 hope this (and the attached link) help.