The purpose of this Evidence Review column is to provide information about current literature of relevance to plastic and aesthetic nurses.
As the skin ages, it becomes thinner. This is due to a decrease in the amount of skin collagen and a reduction in the elastic fibers contained within the skin. These changes begin at approximately 30 years of age. In addition to age-related skin changes, there are changes that occur within the facial skeleton. These changes include a reduction in facial height, an increase in facial width, and a retrusion of the upper jaw caused by bony resorption. The changes that occur to the midface as an individual ages are of great interest to plastic and aesthetic nurses because the soft tissue is most often targeted during attempts to rejuvenate the aged face (Serra-Renom & Serra-Mestre, 2016).
There are two schools of thought related to midfacial aging: the gravitational theory and the volume-loss theory. The gravitational theory proposes that facial aging occurs as a result of anatomical changes such as bone remodeling, tissue descent secondary to gravitational pull, attenuation of the retaining facial ligaments, and atrophy of the fat compartments. The volume-loss theory proposes that facial aging occurs as a result of atrophy of compartmentalized facial fat.
Boehm et al. (2020) conducted a longitudinal study to quantify age-related volume changes occurring within the superficial, deep, and buccal fat compartments of the midface. The researchers evaluated individuals aged 30-65 years who underwent a facial computed tomographic (CT) scan, followed by a second facial CT scan 10 or more years after the first CT scan. For each patient, the researchers calculated the volume of the total midface (i.e., superficial plus deep plus buccal fat), superficial and deep fat only, and superficial fat only.
A total of 19 of 498 screened patients were included in the study. Notably, at the .01 significance level, a sample size of 19 patients provided more than 90% power for all primary outcomes. The median initial age of the study participants was 45.9 years (range = 31-65 years). The mean final age of the participants was 57.3 years (range = 41-77 years). Of the 19 participants, 14 (74%) were women and 5 (26%) were men. The average time interval between CT scans was 11.3 years (range = 10-13 years).
The researchers found that the mean total fat volume of the midface decreased significantly from 46.47 to 40.81 cm3 (p < .01). The mean superficial fat volume decreased significantly from 26.10 to 23.15 cm3 (p < .01). The mean deep fat volume decreased significantly from 11.01 to 8.98 cm3 (p < .01). During the study period, the participants lost an average of 11.3% of their superficial fat volume and 18.4% of their deep fat volume. There was no significant difference in the amount of buccal fat volume (9.36-8.68 cm3; p = .04).
The results of this study show that as an individual ages, there is a measurable loss of midface fat volume. These results provide support for the volume-loss theory for facial aging. When volume is lost from the deep midface fat compartment, there is a loss of foundational support for the midface that leads to the development of a "ptosis" of the overlying superficial fat that deepens the nasolabial fold. The subsequent loss of superficial fat contributes to the deflated appearance of the skin envelope.
The researchers posited that the study interval of 11.3 years may have been too short to capture greater changes in midface fat volume. Furthermore, although the sample size was large enough to achieve more than 90% power, it remains a small sample size. Similar studies with larger samples conducted over a longer period of time may better characterize age-related changes in midface facial fat and the rate of the changes that occur.
If you have read or know about an important study relevant to plastic and aesthetic nurses and would like to write about it or see it presented in the Evidence Review column of Plastic Surgical Nursing, please contact Sharon Ann Van Wicklin, Editor-in-Chief, atmailto:[email protected].
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