The Significance of Outer Retinal Injury in Glaucoma
Chronic glaucoma results in the loss of retinal ganglion cells. Much of basic glaucoma research has, appropriately, focused on these cells and their axonal connections as they pass through the optic nerve. However, previous work by the principal investigator and by other laboratories have now established that the outer retina (specifically, the photoreceptors) is also affected in both human chronic glaucoma and in a non-human primate model of chronic glaucoma. The significance of this finding is unknown. Dr. Nork plans to apply new research methodologies for examining the relationship between the blood supply to the outer retina and the retinal pathology found in glaucoma.Blindness in glaucoma is caused by retinal ganglion cell loss. Direct injury (either mechanical or vascular) to the optic nerve most likely represents a significant effect. Even so, outer retinal ischemia may play a contributory role in RGC death. With this research into the regional effects of retinal damage in animal models of glaucoma, Dr. Nork hopes to test if outer and inner retinal injury in glaucoma are related. If these and other studies show this to be the case, it could lead to new pathways for pharmacologic intervention in this often inadequately controlled disease process.
Nork TM, Kim CB, Shanmuganayagam D, Van Lysel MS, Ver Hoeve JN, Folts JD. Measurement of regional choroidal blood flow in rabbits and monkeys using fluorescent microspheres. Arch Ophthalmol. 2006 Jun;124(6):860-8.
Maertz NA, Kim CB, Nork TM, Levin LA, Lucarelli MJ, Kaufman PL, Ver Hoeve JN. Multifocal visual evoked potentials in the anesthetized non-human primate. Curr Eye Res. 2006 Oct;31(10):885-93.
Pelzel HR, Schlamp CL, Poulsen GL, Ver Hoeve JA, Nork TM, Nickells RW. Decrease of cone opsin mRNA in experimental ocular hypertension. Mol Vis. 2006 Oct 26;12:1272-82.
First published on: June 10, 2008
Last modified on: June 11, 2008