Do sizers and/or the rice test underestimate final implant size if submuscular?

Thank you for your question. I would say both the surgeons you consulted with are correct. In the hands of an experienced surgeon, sizers, or actual implants in a sports bra can be a very accurate representation of the final outcome. In fact, this is often more accurate than the various imaging systems in the market. Experience is the key. After having done a few thousand such procedures, a typical plastic surgeon develops a very good idea of what size a particular patient wants, or what will work best for them. Balance, appearance  and proportion are more important than actual volume. There is some shrinkage when placed under the muscle, so many surgeons will suggest going one implant size up to compensate for this. Because a patient becomes very accustomed to whatever size implant is placed, most surgeons suggest going with the larger of the two choices as this results in greater patient satisfaction.

Hi, thank you for your inquiry. Sizer can give us a good idea of what we would look like post surgery. Given your height and weight, because you are relatively small, minute differences can have a greater impact on you. I would see a board certified plastic surgeon to get correct anatomical measurements on you to decipher which implant size would look best for what you have envisioned. 

In my opinion, sizers in general do not correlate well with actual implant size, they only give some idea how a patient wants to look in a bra or clothing. You should not be having to experience anxiety over wether to select 275cc or 295cc , as most patients would not be able to descern the difference. A number of factors must be considered when selecting the correct implant for a patient , and only your surgeon has the knowledge and experience to correctly do so....that is their job! In our practice, patients show us how they want their breasts to look, and we take the responsibility of making the correct selection.

Great question!  Unfortunately nothing is 100% accurate and no surgeon will every promise any of these maneuvers will by 100% accurate either.  I agree that the sizers used will have about a 10% loss in volume once its in the body.  The difference between a 275cc and 295cc is actually only 1/2 a shot glass as one shot glass is 40cc's and therefore almost negligable.  Review your options with your surgeon and go with your gut feeling.Best of luck and hope this information helps!
- Dr. Roger Tsai  @DrRogerTsai
Board Certified Plastic Surgeon

Dear chi24,
breast implant type and sizing selection is a complicated process and requires a detailed consultation that includes a discussion of your goals, a detailed examination, and a lengthy discussion. But the decision will always start and end with the patient. When it comes to sizing, we have all of our patients find 3 photos of their desired breast size. We ask for naked breast photos because clothing can obscure the true size (push up bras). Next, we consult with patients and go over the photos and take detailed breast measurements during a physical exam. Next, we using a sizing algorithm to determine a range of implants that will work based on the exam and the measurements.Lastly, during the operation, we use silicone sizers in the operating room to see how the size actually looks in the breast. We sit the patient up in the operating room, while asleep of course, and compare the sizer result with their desired look photos. If it is too small, we start the process over with a slightly larger implant. We don't stop until we get the perfect match.Of all of my breast augmentation patients, every one of them has been happy with their size due to this detailed and meticulous process. You don't want to invest time and money into a result that is either too big or too small.You should discuss your concerns with a board-certified plastic surgeon and make sure that your surgeon understands your goals.
Daniel Barrett, MD

This is a classic example of a question that, if you asked 10 different plastic surgeons, you'd get 15 different answers. In general, if you are concerned that your implants may end up looking too small then just go with the larger of the two. As you said, its a shot glass worth, so to be honest you'll never know the difference after the fact, so best to prevent the potential regret by knowing you chose the larger size if after surgery you do feel like they are smaller than you were hoping for. Hope that helps! 

I use sizers to help patients visualize their breast size, but it is not an exact science. The more flat chested you are, the closer the sizers or rice test is to what you will look like after surgery. The more breast tissue and breast sag that you have, the less accurate they tend to be. Typically, patients in my practice get down to two or three implant sizes then I use sizers intraoperatively to make the final decision based on their preoperative goals. I usually ask patients in your situation whether they want to go with the smaller or larger size if they both look good. In general, patients who choose the larger of the two sizes have a lower likelihood of "I wish I had gone a little bigger" than those who choose the smaller implant.

breast sizers are an approximation and some feel they are more useful than others.  You are right that 20 cc is not much difference.  Both sizes are on the smallish side so even if you go with the 295 it’s not going to make you huge.

In my opinion, sizers really only give you a general idea of what things will look like with regards to the volume. So much depends on your tissues, elasticity, type of implant used, muscle strength, etc.  For one patient, a sizer may very closely replicate the final volume, while another it may off quite a bit.  Every patient is different, and why implant choice is based on a bunch of different factors.  In your case, if your board surgeon plastic surgeon feels that either of those two sizes will work, then I always recommend going with the slightly larger one.  It really is only a tablespoon or two difference at the most.   95% of patients all think they should have gone a little larger once they are healed.  I hope this helps.

Patients often think in terms of cup size when considering augmentation. Unfortunately, devices are sized in terms of milliliters (cc) of volume. This can lead to some confusion when sizing. Additionally, it is important to remember that cup size itself is not standardized with variations from one manufacturer to another. Unfortunately, as many women can attest their cup size in an industry leader such as VS is not necessarily transferable to another brand.
Another point which is often under appreciated is that of anatomy and starting point. Any implant will add volume to the volume which is already present. The implant is additive. A particular volume will not necessarily confer the same cup size to different patients (often times it will not even confer the same cup size to different breasts in the same individual...remember they are "sisters" not "twins"). 
A general rule of thumb is that 125cc can represent somewhere between 1/2 to a full cup size increase. Smaller volume differentials (25-50cc) are typically less consequential representing a volume change of less than a shot glass. However, I have found these numbers, at least anecdotally, to be of little help. Patients often present with notions/goals which do not correlate with these sorts of sterile volumetric assessments.
When sizing patients, there are a number of useful tools including:
-3D imaging (has the added benefit of offering a volumetric analysis of the pre-operative breast)
-Breast sizers (rice bags)
-Goal photos
I also recommend that patients commit to a particular look rather than a cup size. Once a patient settles on a look that pleases them the overall cup size increase becomes less relevant.The key to obtaining a natural result is to stay within the parameters defined by your BWD.With regards to your specific question, there is no 100% accurate way to predict post op size. Submuscular augmentation does make a slight difference in projection (even if it were 10%-that would represent millimeters). I would not struggle mightily over 20 cc ( less than half a shot glass). Ultimately, if you find that the 295 cc is too large, the 20 cc differential is unlikely to have made a difference. That being said, in smaller framed individuals conservative sizing is key to achieving a "natural" result.
As always, discuss your concerns with a board certified plastic surgeon (ABPS).
Donovan Rosas MD
Board Certified by the American Board of Plastic Surgery
Member: American Society for Aesthetic Plastic Surgery, American Society of Plastic Surgeons
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