Abstract
Purpose :
A first in class drug, deoxycholic acid (10mg/ml) was recently approved for reduction of submental fat. One of the rare but serious complications observed with its administration is damage to the marginal mandibular nerve. In this study, we evaluated if deoxycholic acid directly induces histologic damage to fresh cadaveric marginal mandibular nerve (MMN).
Methods :
A segment of MMN was harvested from twelve hemifaces of 6 fresh cadavers. The nerve specimen was exposed to either 0.9% sterile saline for 24 hours, deoxycholic acid (10mg/ml) for 20 minutes, or deoxycholic acid (10mg/ml) for 24 hours. Tissue fixed in glutaraldehyde for 24 then embedded in plastic and sectioned. Toluidine blue stained sections were qualitatively evaluated for stain intensity using light microscopy.
Results :
Toluidine blue staining was less in the marginal mandibular nerve exposed to deoxycholic acid when compared to saline. The specimen exposed to deoxycholic acid for 24 hours showed less toluidine blue staining that that of the nerve exposed to dexoycholic acid for 20 minutes. Transmission electron microscopy of submental fat exposed to deoxycholic acid revealed disruption of adipocyte integrity and surrounding reticular meshwork when compared to specimens only exposed to saline.
Conclusions :
Deoxycholic acid (10mg/ml) treated marginal mandibular nerve causes direct damage to the myelin sheath in fresh human cadaver specimens. Direct neurotoxic effect of deoxycholic acid may be responsible for marginal mandibular nerve injury in patients. Myelin damage seen in the marginal mandibular nerve should caution the use of deoxycholic acid in the periocular region.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.