Distribution of submental fat in relationship to the platysma muscle

The results of submental lipectomy often remain suboptimal, and in some cases this may be due to the presence of residual fat deep to the platysma muscle. This study was undertaken to determine the relative amounts of fat superficial and deep to the platysma muscle. A dissection of the submental region of 20 cadavers revealed a mean weight of fat lying superficial to the platysma muscle of 8.4 grams. The mean weight of fat lying deep to the platysma muscle but superficial to the mylohyoid muscle was 3.7 grams. In three cases (15%), the weight of fat deep to the platysma muscle was greater than 50% of the total fat. This is of significance with respect to those submental lipectomy procedures that normally address only the fat superficial to the platysma.