老化對人類眼輪匝肌組織型態特徵之影響

Orbicularis oculi muscle is a key structure in the peri-orbital anatomy and is
responsible for the major changes of aging in this area. Peri-orbital rejuvenation has
been an issue of great interest in plastic surgery. We believe that understanding the
age-related changes in orbicularis oculi muscle is important for improving the current
rejuvenation techniques or developing the new ones. Nevertheless, a study focusing
on this topic has never been performed before, simply because it is difficult and
dangerous to perform needle biopsy on orbicularis oculi muscle.
We recruited patients who received upper blepharoplasty in National Taiwan
University Hospital as our subjects. Taking advantage of the discarded soft tissue in
the blepharoplasty surgery, samples of orbicularis oculi muscle can be easily obtained
from patients of various ages.
In our study, the muscle specimens are mounted for transverse section and frozen
in liquid propane chilled with liquid nitrogen. Muscle fiber types can be classified
2
with myofibrillar ATPase staining. The ATPase-stained muscle sections were
processed as a videoprint. Suitable areas of each section containing transversely cut
muscle fibers were photographed. The image file was processed with an image
analysis system. The number of each fiber per photographed area and the cross
sectional area of each fiber can be determined.
By dividing the subjects who had their orbicularis oculi muscle sampled during
upper blepharoplasty operation into age groups, the different muscle type
compositions can be compared among the different groups. Therefore, the age-related
changes in fiber type compositions fiber cross section areas of human orbicularis oculi
muscle can be concluded.