Estimating the Weight of abdominal flaps for Breast Reconstruction with MRA
Another nifty application of MRA (magnetic resonance angiography) technology in breast reconstruction is estimating the weight of the flap tissue taken from the donor site (usually a DIEP flap or SIEA flap from the abdomen). This gives the surgeon some idea of how big the flap will be, and thus how big the breast reconstruction will be. The ability to do this requires the close working relationship of the radiologist, who has learned how we design our flaps. After the MRA images are acquired, 3D processing is done on a computer station. The volume of the tissue is calculated using software, and then converted to grams.
In approximately 45 abdominal perforator flap breast reconstructions, there was only on average a 47 gram difference (7.5%) between the actual weight of the abdominal flap (weighed in the operating room) and the estimated weight of the abdominal flap using MRA. The reasons why there were not 100% accuracy are: Dr. Vasile will sometimes bevel during the flap dissection to take more fat than what is originally marked on the skin, the calculations are made using the mean density of fat only, and extra tissue was taken with the abdominal flap in 2 of the 45 flaps because an inguinal lymph node was included for a microsurgical lymph node transfer procedure to treat arm lymphedema after axillary node dissection.
This above work was presented by Dr. Vasile at the American Society of Plastic Surgeons Meeting in Seattle, Washington in October 2009.