Abstract
Purpose :
Lax eyelid syndrome (LES) is the combination of distensible “floppy” eyelids and chronic papillary conjunctivitis and can present in patients with obstructive sleep apnea (OSA). Loss of elastin is a feature of LES and has been found to be co-localized with MMP-9 in eyelids of OSA patients. MMP-9 is also elevated in peripheral blood of patients with OSA. Elastin disruption has been demonstrated in soft palate histological specimens of OSA patients following uvulopalatopharyngoplasty. This study evaluated the relationship between OSA, obesity, and elastin content in skin, orbital tissue, optic nerve and trabecular meshwork of patients with known OSA compared to healthy controls.
Methods :
Globe specimens were obtained from Eversight Eye Bank for analysis of optic nerve, lamina cribosa, trabecular meshwork, and orbital tissue. Skin biopsies of non-inflammatory conditions from patients who had sleep studies were analyzed. Comparison was made between elastin content in the above tissues among four independent groups of patients: obese with OSA, obese without OSA, non-obese with OSA, non-obese without OSA. Using Verhoeff –Van Gieson stain, a pathologist, blinded to the groups, determined morphology and quantity of elastin.
Results :
There were no statistical differences in elastin content between the four groups in either superficial or deep dermal layers (p = 0.34; p = 0.68). There was a statistically significant difference in elastin content between the obese and non-obese groups in the superficial but not deep dermal layer (p = 0.049; p = 0.53). There were no differences between the OSA and non-OSA groups for either superficial or deep layers (p = 0.57). The optic nerve, trabecular meshwork and periorbital soft tissue samples displayed few and fragmented elastin fibers in patients with OSA and obesity, but were difficult to assess.
Conclusions :
Skin biopsy specimens showed no difference in the number of elastin fibers in the superficial or deep dermal layers in patients with OSA and without OSA. There was a statistically significant difference between the number of elastin fibers in patients with obesity when compared to patients without obesity, regardless of whether the patients had OSA or not. This might reflect that the systemic inflammation caused by obesity leads to differential expression of MMPs. Further work is necessary to determine any role of OSA in the ocular tissues.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.