Basic Consideration for Facial Aging: Age-Related Changes of the Bony Orbit and Orbicularis Oculi Muscle in East Asians

Abstract

Background Age-related changes in the periocular areas are mainly caused by anatomical changes of the bony orbit and orbicularis oculi muscle (OOM). To achieve effective rejuvenation, it is necessary to understand these anatomical changes according to age. Objectives We analyzed the configuration of the bony orbit and OOM using computed tomography (CT) and evaluated the effects of aging on these structures. Methods A total of 220 orbits and OOMs of 110 Japanese participants (55 males, 55 females) aged 20-87 years were enrolled. The long diameter of the orbits, orbital ellipticity, OOM thickness, and OOM attachment to the inferior orbital rim were analyzed. These variables were statistically evaluated for their relationship with age. Results The long diameter of the orbit was significantly longer in those over than in those under 60 years, with a moderate and significant positive correlation between orbital ellipticity and age. OOM thickness and age showed a strong negative correlation. The degree of OOM attachment to the inferior orbital rim decreased significantly with age. Conclusions This study showed that age-related changes of the bony orbit in Japanese individuals tended to be the same as those in Caucasians, but there were differences in degree of changes observed. As a new finding in the Japanese population, the OOM not only thins with aging, but also gradually loosens from the facial bone. In the elderly, only the nasal side of the OOM was attached to the bone. In clinical application, this could contribute to the development of cosmetic surgeries.

Objective Analysis of Age-Related Changes in the Superficial Musculoaponeurotic System in Japanese Females Using Computed Tomography

“…This study showed that the SMAS, like muscles of facial expression, 8 become thinner with aging, suggesting that it is involved in mechanisms of facial aging. In the future, if the aging mechanism of SMAS is elucidated in more detail, it may be possible to apply it to nonsurgical facial rejuvenation therapy and help develop more effective and safer facelift surgeries.…”

“…In 2019, Okuda et al 5 reported that SMAS laxity increases due to aging. Furthermore, in a report by Okuda et al 8 in 2022, it was shown that the orbicularis oculi muscle became thinner due to aging. Additionally, it has been shown that the lateral part of the orbicularis oculi muscle, lateral canthal tendon, and major zygomatic muscle droop with aging when standing.…”

“…Current CT technology provides high-resolution images, allowing detailed visualization of facial appearance and subcutaneous structure changes. 3 , 8 The workstation used for data capture also housed an imaging analysis system that can create various 3D CT images. 3 , 5 …”

“… 3 , 15 These tissues are known to depreciate with aging. 8 , 16 , 17 It is inferred that these tissue reductions lead to SMAS thinning. In addition, thinning of the SMAS with aging could lead to sagging cheeks due to loosening of its supportive force.…”

“…Therefore, we used computed tomography (CT) technology with a high spatial resolution to address this challenge. 3 , 5 , 8 In anatomical imaging, the SMAS is recognizable as a linear subcutaneous fibromuscular structure. 3 , 5 One limitation of SMAS analysis is that its thickness varies depending on the facial region.…”