Optometrists work to stop glaucoma from stealing sight
Promising research by a trio of optometrists may help halt the sight-robbing effects of glaucoma, the second-leading cause of blindness worldwide.
Glaucoma has been called the "silent thief of sight."
The research focuses on early detection—especially important because early detection of glaucoma increases the chances of stopping or slowing the disease's progression.
Thom Freddo, O.D., Ph.D., of Canada's University of Waterloo College of Optometry and Vision Science; Brad Fortune, O.D., Ph.D., of Portland, Oregon's Devers Eye Institute Research Laboratories; and Nimesh Patel, O.D., Ph.D., of the University of Houston College of Optometry (UHCO) reported on their work during the annual Ezell Fellowship lecture Oct. 24 at the American Academy of Optometry (AAO) meeting in San Diego.
Optometrists may be able to translate some of their advancements into practice in the near future, noted Laura Frishman, Ph.D., of UHCO, who moderated the event. Their work also may benefit patients with or at-risk for glaucoma in the near future.
Better imaging, better detection
Research shows two important new ways glaucoma may be detected earlier, Drs. Fortune and Patel reported.
Studies in experimental models suggest retinal ganglion cell axons exhibit structural and functional axonopathy—caused by injury in the deforming optic nerve head (ONH)—before they disappear from the retinal nerve fiber layer, Dr. Fortune explained.
With this knowledge, optometrists can use optical coherence tomography (OCT), scanning laser polarimetry and confocal scanning laser ophthalmoscopy to detect such axonopathy in the course of retinal and ONH imaging, he noted.
In addition, research links structural changes within the posterior pole with glaucomatous optic neuropathy, Dr. Patel said. Optometrists can use OCT to check for these structural changes, thereby detecting neuropathy at an early stage.
Research leads to treatments
Research is also producing promising new treatments for glaucoma. Improved understanding of aqueous outflow in the eye is leading to new pharmaceuticals intended to control ocular hypertension (OHT) by reducing outflow resistance, Dr. Freddo said. Preliminary clinical trials data suggest the new drugs are safe and effective.
Glaucoma affects one in 200 people age 50 and younger and one in 10 age 80 and older. It has been called the "silent thief of sight" because the loss of vision often occurs gradually over a long period of time, and symptoms occur only when the disease is quite advanced. Once lost, the vision cannot normally be recovered, so early detection and treatments aimed at preventing further loss are both promising steps forward for these patients.