Résumé
Objective To study the mechanism of tear trough deformity and palabromalar groove deformity.Methods Four old cadavers (2 male,2 female,an average age of 67.2 years) with obvious tear trough deformity and palpbromalar groove deformity and 4 young cadavers (2 male,2 female,an average age of 23.5 years) without tear trough deformity and palpbromalar groove deformity were selected and dissected and histological observation were performed on lower eyelid and periorbital region.Results Compared to young specimens,the skin and orbicularis oculi muscle of old specimens were atrophy and relaxed.Tear trough deformity and palabromalar groove deformity overlaid the junction of thinner eyelid skin and thicker cheek skin.The superior border of the malar fat pad covered the junction of the palpebral and orbital portions of the orbicularis muscle,and correlated with the tear trough and palpbromalar groove,but the superior border of the malar fat pad in young cadavers was found above the tear trough and palpbromalar groove line.The orbicularis retaining ligament arose from the orbital rim and caudal to the junction of the palpebral and orbital portions of the orbicularis muscle,and it was relaxed in old group than that in young group.Conclusions Tear trough deformity and palabromalar groove deformity result from combination of age-related relaxation,atrophy and descent of layers of tissues.The orbital septal and the orbicularis retaining ligament prevent tissues from descending,which makes tear trough deformity and palabromalar groove deformity more visible.