[1] Univ Calif Los Angeles, David Geffen Sch Med, Dept Head & Neck Surg, 200 UCLA Med Plaza,Suite 550, Los Angeles, CA 90095 USA
[2] Univ Calif Los Angeles, David Geffen Sch Med, Dept Neurosurg, Los Angeles, CA 90095 USA
[3] Univ Calif Los Angeles, David Geffen Sch Med, Div Endocrinol Diabet & Metab, Los Angeles, CA 90095 USA