Histological investigation of liposuctioned fat for injection laryngoplasty

There are a few injectable biomaterials used in vocal-fold-augmentation surgery. In this study, liposuctioned autologous fat, used as the injection material, was investigated histologically.

Liposuctioned fat, which was harvested from 13 patients during injection laryngoplasty, was examined by light and electron microscopy.

The cell membranes of most of the liposuctioned fat had not been damaged during harvesting and microinjection by our method. The harvested liposuctioned fat was a group of unilocular fat cells. Each cell was surrounded by a meshwork of fine reticular fibers. The cells were spherical and about 30 to 130 microm in diameter. The cells size and density were different from individual to individual. The diameters of liposuctioned fat cells were correlated with the body mass index. Dense and small fat cells were able to maintain graft volume. Sparse and large fat cells tended to not be able to maintain graft volume. There was little proliferation of unilocular fat cells, which were not able to maintain graft volume.

The structure consisting of a unilocular cell, containing a single droplet of lipid, surrounded by a meshwork of delicate reticular fiber is one of the reasons why autologous fat has viscous properties similar to those of human lamina propria. Autologous fat was not damaged by our harvesting and microinjection method. The size, density and proliferation of fat cells, and ground substance around them may be related to resorption and a decrease in surviving graft volume.