Comparison of laser and circumlimbal suture induced elevation of intraocular pressure in albino CD-1 mice

TitleComparison of laser and circumlimbal suture induced elevation of intraocular pressure in albino CD-1 mice
Publication TypeJournal Article
Year of Publication2017
AuthorsLiu, H. - H., L. Zhang, M. Shi, L. Chen, and J. Flanagan
JournalPLoS ONE
Keywordsadult, animal, animal experiment, animal model, animal tissue, Animals, Article, circumlimbal suture, comparative study, controlled study, episcleral vein, intermethod comparison, intraocular hypertension, intraocular pressure, laser coagulation, male, Mice, monitoring, mouse, nonhuman, ocular blood vessel, Ocular Hypertension, Optical coherence tomography, pathology, pathophysiology, retina, retina ganglion cell, retina ischemia, Retinal Ganglion Cells, retinal nerve fiber layer, suture, suture technique, Sutures, young adult

Animal models of ocular hypertension are important tools for glaucoma studies. Both acute transient models and chronic models of ocular hypertension may be useful to investigate specific aspects of neurodegeneration. In this study, we compare the intraocular pressure (IOP) and inner retinal changes induced by 1) laser photocoagulation of both episcleral veins and limbal vessels and 2) circumlimbal suture in CD-1 mice. The suture group is divided into 3 subgroups depending on the level of the immediate IOP spike (acute > 55 mmHg or chronic < 55 mmHg) and time period of monitoring (7 or 28 days). The laser group is followed for 7 days. IOP data show that it peaks at 5 hours and returns to normal level within 7 days in the laser group. In all suture groups, IOP spikes initially and decreases gradually, but it remains significantly elevated at 7 days. In 7 days, the acute suture model generates rapid loss of retinal nerve fiber layer (RNFL) and retinal ganglion cells (RGCs) when compared to the gradual loss by the chronic suture model, possibly due to retinal ischemia and reperfusion within the first few hours after treatment. The laser model falls between the acute suture and chronic suture models resulting in less RNFL and RGC loss than the acute suture model but significantly more loss than the chronic suture model. These results suggest that when using suture models of IOP elevation, it is critical to take the initial IOP spike into consideration and to choose between the acute and chronic models depending on respective research purposes. © 2017 Liu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.