Kim JW, et al. - Experts radiographically and histologically characterized the tongue base tissues removed after robotic surgery and evaluated their relationship with polysomnographic measurements in obstructive sleep apnea. Four distinctive layers including epithelial, lymphoid follicular, glandular and muscular layers were comprised by the tongue base tissue removed by transoral robotic surgery in OSA patients. Discrimination of these layered structures could also be done in the CT images.