Abstract
Purpose :
Tenon’s capsule fascia is encountered during strabismus surgery, but its composition and function remain poorly understood. As a result, there is no consensus whether Tenon’s fascia in the surgical field should be minimally disrupted or excised widely. This study tested the hypothesis that there are differences in the composition and abundance of Tenon’s capsule proteins with aging and after strabismus surgery.
Methods :
Tenon’s capsule samples were collected from 40 subjects who were undergoing strabismus surgery. Samples were collected from subjects in 3 age groups:
a) children (<18 years old)
b) adults (18 to <55 years old)
c) older adults (55 years and older)
Each group had 2 subgroups: surgically naïve (SN) subjects and subjects who had prior strabismus surgery (PSS). Samples were collected from 6 subjects in each of the 6 subgroups.
Data from 30 randomized subject samples were analyzed by liquid chromatography with tandem mass spectrometry. Protein abundance was deemed statistically significant between subject groups if absolute average log2 >0.58 and Q value <0.05.
Results :
In total, 194 proteins had statistically significant differences in abundance between subject groups.
Type I and type III collagen were found to decrease with age in SN subjects. SN children had 5-fold more abundant type I collagen compared to SN adults (p = 0.02) and 12-fold compared to SN older adults (p < 0.001). Type III collagen was 24-fold more abundant in SN children than SN older adults (p < 0.001). In PSS subjects, children had 3-fold more abundant type I collagen than adults (p < 0.001) and 2.6-fold more abundant than older adults (p = 0.002). Type III collagen was 3.5-fold more abundant in children than adults (p < 0.001) and 2.4-fold more abundant than in older adults (p = 0.02).
Type I and type III collagen was less abundant in PSS subjects compared to SN subjects. Type I collagen was 2.2-fold more abundant in SN subjects than in PSS subjects (p < 0.001), while type III collagen was 2.4-fold more abundant (p < 0.001).
Conclusions :
Our results confirm our hypothesis that the protein composition of Tenon’s fascia changes with age and prior strabismus surgery. The decrease in collagen with age was consistent with the authors’ observation that Tenon’s fascia is thick in children and thin in older adults. The decrease in collagen in subjects with prior strabismus surgery was unexpected as scar tissue is comprised of these proteins.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.