Lower Pole Stretch / Inferior Implant Malposition
Lower pole (the lower pole is the lower part of the breast) stretch, or "bottoming out" really represents a spectrum of two separate deformities. All breast implants cause lower pole stretch by definition. If the lower pole of the breast did not stretch, then the implant could not be placed inside the breast. The issue here is when the lower pole stretch becomes excessive, enough to compromise the aesthetic appearance of the breast. I have patients who are very tolerant of significant lower pole stretch and some who are not very tolerant of even moderate amounts of stretch. Mild lower pole stretch essentially goes unnoticed.
For each size implant, there is an ideal distance from nipple to lower breast crease. When this distance is exceeded, the breast becomes very "bottom-heavy" and the nipple tends to ride higher up on the breast mound, tilting upward. There is also loss of upper pole fullness as the available breast implant volume begins to migrate to the lower portion of the breast. This is what is meant by "lower pole stretch."
Lower pole stretch can be the result of lengthening of the lower pole of the breast alone, inferior displacement of the inframammary fold (lower breast crease), or a combination of both of these.
How I Assess a Breast for Lower Pole Stretch/Inferior implant malposition
When I assess a breast for lower pole stretch, there are two things to consider:
1. Was there stretching of the breast from nipple to the original post-augmentation lower breast crease?
2. Did the original post-augmentation lower breast crease migrate downward?
As I always plan my surgeries such that the scar ends up in the crease at the end of surgery, the scar is a marker for the original post-augmentation crease. This is an important reference point. Note: sometimes I make the surgical incision in the natural preoperative breast crease, sometimes I lower the crease to accommodate the implant. That is an entirely different discussion. The key point to remember is that I plan for the scar to always be in the crease of the breast at the end of surgery. Whether I planned to lower the preoperative crease before augmentation is irrelevant.
Isolated Lower Pole Stretch
Isolated lower pole stretch refers to stretching of the lower breast tissue alone. Therefore, I am referring to the distance from nipple to the surgical scar. As long as the surgical scar remains in the same place, the implant itself remains in the same position on the chest. If the nipple to surgical scar distance increases, and the scar remains in the original location, then there is isolated lower pole stretch. In this case, the lower breast has stretched and volume from the upper portion of the breast will shift to the lower breast. This will result in some loss of fullness of the upper breast. Essentially, the implant stays in the same location as originally placed, but it reshapes so that most of the volume of the implant is in the lower portion of the breast, yielding a full, rounded lower breast. In most cases, the breast will still maintain an attractive, natural look and not require any surgical revision.
Inferior Migration of the Lower Breast Crease
The important difference to recognize is that when there is inferior displacement of the lower breast crease, the breast implant will also migrate downward as the lower edge of the implant rests on the lower breast crease. The end result is that the breast mound also appears lower on the chest wall. This is important to know if one is contemplating surgical correction. It is imperative to understand the anatomy and the cause of a deformity in order to formulate a corrective surgical plan. The surgeon needs to understand if the problem is due to stretching of the lower pole of the breast, lowering of the lower breast crease or a combination of the two. This will allow the surgeon the best opportunity to formulate the most optimal surgical plan for correction of the deformity.
There are three possibilities causing the breast to appear "bottomed out":
1. Isolated stretching of the lower portion of the breast, breast crease is in original location
2. No stretching of the lower portion of the breast, breast crease has migrated downward
3. A combination of the first two.
The below diagram illustrates the difference between Isolated Lower Pole Stretch and Inferior Migration of the Lower Breast Crease.
Left: Breast implants at the correct level on the chest wall, with no lower pole stretch or malposition. The horizontal lines (top to bottom) depict the correct position for the upper border of the areola, the lower edge of the implant (lower breast crease) and an example of inferior migration of the lower breast crease.
Middle: Isolated lower pole stretch. The lower breast crease is maintained in the proper position, however, the lower pole of the breast has stretched with some descent of the lower pole of the breast and nipple, however, the overall aesthetic result is not significantly compromised.
Right: Inferior migration of the lower breast crease. The lower breast crease has descended inferiorly, resulting in descent of the implant, severe loss of upper breast fullness, misshapen breast contours and superior displacement of the nipple.