Exploring a New Region of the Eye Using OCTA for Early Diagnosis in Glaucoma – Richter Lab
A Focus on Research – An Impact on Patient Care
“Discovering sensitive diagnostic methods such as OCTA to detect early stages of the disease is paramount to treating glaucoma patients and preventing devastating vision loss.” –Grace M. Richter, MD, MPH
Grace Richter, MD, MPH, assistant professor of clinical ophthalmology and glaucoma specialist has focused her career on ocular epidemiology and the development of advanced diagnostics technologies for early diagnosis of glaucoma.
Structural and Functional Associations of Macular Microcirculation in the Ganglion Cell-Inner Plexiform Layer in Glaucoma Using Optical Coherence Tomography Angiography. Richter GM, Madi I, Chu Z, Burkemper B, Chang R, Zaman A, Sylvester B, Reznik A, Kashani A, Wang RK, Varma R. J Glaucoma. 2018 Mar;27(3):281-90. https://www.ncbi.nlm.nih.gov/pubmed/29394201
Glaucoma is the second leading cause of blindness in the world according the World Health Organization. It is estimated that almost 2.7 million Americans have glaucoma with over half who have gone undiagnosed. If left untreated, glaucoma can cause irreversible vision loss. Primary open-angle glaucoma (POAG), the most common form of glaucoma in the nation, causes damage to the optic nerve (the nerve responsible for transmitting visual information to the brain). This optic nerve damage is characterized by progressive degeneration of retinal ganglion cells (RGCs) and their axons.
Given that POAG can lead to permanent vision loss, early diagnosis and intervention is key. Richter and her team of experts have studied a new way to image the RGC layer, specifically in the macula, the region of the retina found in the back of the eye which contains the highest concentration of RGCs. Using a highly sophisticated imaging modality known as optical coherence tomography angiography (OCTA), Richter has been able to quantify the retinal microvasculature or the blood vessels within this region and improve our understanding of the functional and structural status of glaucoma from this vascular data. Richter’s lab demonstrated that microcirculation in the macula was significantly reduced in glaucoma patients and that OCTA offers great promise as a diagnostic tool in glaucoma that may even offer novel insight into the functional status of the retinal ganglion cells.
Imaging the microvasculature of the macula in glaucoma has been relatively underexplored using OCTA. Thus far research has suggested that imaging this region will likely supplement current diagnostic tools of POAG. Detection of early changes in the microvasculature of the macula region is highly correlated with early functional changes and may serve as an early marker in the diagnosis of POAG. In addition, imaging the macula using OCTA can lead to a greater understanding of the pathophysiology of this disease and thus improve our ability to treat it at an early stage.
Further research must be conducted to improve the protocol for imaging within this region, including number of scans taken and optimizing quantification algorithms, and to study OCTA changes in the macula longitudinally before OCTA can be used as a diagnostic tool in a clinical setting.