Abstract
Purpose :
Controversy exists regarding the safety of scleral collagen cross-linking(CXL) by riboflavin/ultraviolet A(UVA). In this study, retina and choroid biological parameters were observed on rhesus monkeys eyes to evaluate the biological changes in early period postoperatively of scleral CXL by riboflavin/UVA on rhesus monkeys sclera.
Methods :
Four 3-year-old male rhesus monkeys(8 eyes) were observed in this study, with scleral CXL procedures applied on superior temporal equatorial sclera on random eyes of all rhesus. CXL was performed with topical riboflavin solution (0.1%) followed by irradiation with ultraviolet A (370nm, 3mW/cm2) for 30 min. Optical coherence tomography (OCT) examination was performed before and 1 week, 1 month and 3 months after the CXL operation. The thickness of retina and choroid were analyzed by 9 parts (1, 3, 6 mm ETDRS) and 7 parts (500, 1000, 1500μm to central fovea of macula) respectively, to evaluate changes of retina and choroid biological parameters in different regions after CXL. The data between cross-linked and untreated control eyes were compared using paired samples t-test.
Results :
As for retina parameters, only the thickness of inner temporal part of retina in CXL eyes revealed a significant reduction in 1 week postoperatively(P=0.022). While the thickness of CXL eyes subsequently increase from 1 month postoperatively, and no statistical difference was noted between CXL eyes and control eyes in 1 month and 3 months(P>0.05). Among choroid parameters, the average thickness of 500μm temporally to central fovea of macula part of choroid in CXL eyes revealed a significant reduction in 1 week postoperatively(P=0.017). In 1 month postoperatively, the average thickness of 1500μm temporally to central fovea of macula part of choroid in CXL eyes revealed a significant reduction(P=0.026). While the thickness increase gradually from 3 months postoperatively, and no statistical difference was noted between CXL eyes and control eyes (P>0.05).
Conclusions :
The thickness of retina and choroid may be affected in crosslinked region in early period postoperatively, but it might recover gradually after 3 months. There is no significant change on retina and choroid biological parameters of non-crosslinked region. Further study should be performed to evaluate the long-term effect of scleral CXL in clinical application.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.