Abstract
Purpose :
Ocular surgery is known to be a risk factor for the development or worsening of dry eye. The purpose of this study was to evaluate possible effects of light from an operating microscope with the hyperosmolarity level of the ocular surface using an in-vitro dry eye model.
Methods :
NaCl-induced hyperosmolar stress was used as a surrogate for the pre-operative dry eye. Porcine conjunctival fibroblasts were cultured in media with different osmolarity: 290 mOsM as a control, 350 mOsM and 400 mOsM as hyperosmolar conditions. An in-vitro scratch assay was performed for each condition with 10 minutes of light exposure (10000 ± 1000 lux) afterwards, on 96 well plates to observe the effect of light on wound healing (n=3). Cell viability was assessed by MTT colorimetric assay after light exposure at the 48-hour time point. Wound healing closure was visualized after the light exposure at 24-hour time point by the Live-Dead assay. The wound area was calculated by ImageJ.
Results :
The wound healing closure was significantly slower at the osmolarity of 350 mOsM with the light exposure compared to the same level of osmolarity but without light exposure, after 24-hours of the culture of conjunctival fibroblasts (p=0.007). With the 400 mOsM culture conditions and light exposure, cellular viability was reduced by 30% ± 10% (p<0.05) compared to the same culture conditions without light exposure.
Conclusions :
The results suggest that light from operating microscopes during ophthalmic surgery might adversely affect cell viability and wound healing on the ocular surface and hence might be a potential contributor to dry eye symptoms after ocular surgery. In addition, pre-operative hyperosmolarity has the potential to make the ocular surface more susceptible to light during ocular surgery.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.