Optometry is one of the most technology-based professions in health care. The automated visual field instrument was one of the first computer-driven tools that became a standard in eye care.
Various adaptations of the scanning laser ophthalmoscope followed along in subsequent years and this technology changes so rapidly that we have learned to expect dramatic upgrades every year or two. With each upgrade, we become so much better at caring for the eyes and visual system that it is hard to image how we ever practiced before these innovations.
Initially, these instruments were primarily used to help us manage glaucoma. Glaucoma, a complex ophthalmic disease that can lead to blindness, was traditionally only treated by ophthalmologists. Even as the scope of optometry advanced to include the ability to treat glaucoma, few optometrists were willing to manage this disease.
With the addition of the scanning laser ophthalmoscope, optometrists became much more confident in their involvement, and their treatment of glaucoma increased. As the cost of these instruments decreased, more optometrists entered the arena, and more patients were tested with this technology and then treated appropriately.
As the technology matured, the ability to manage pathology moved beyond glaucoma and improved our ability to manage macular and retinal problems. Our understanding of retinal anatomy and the structural change associated with pathology dramatically improved our confidence to diagnose, refer appropriately and follow patients with these common problems.
The goal post has moved again. The scanning laser ophthalmoscope, in the current form of OCT, has had another upgrade. The leading manufacturers have improved their physical platforms and their software. These upgrades allow a more detailed view of the retinal capillary beds and provide information parallel to fluorescein angiography. This new noninvasive scan is called OCT angiography (OCT-A). Although this technology will improve the management of eye diseases such as macular degeneration, the implications are much broader.
Research with the images that are acquired with the OCT-A has shown that patients with diabetes but no retinopathy will show consistent abnormal changes (Tan et al., Alibhai et al.). These changes in the capillary bed signal that the diabetes has progressed to the “end organ” damage stage, and the disease must be better managed at the systemic level. Current research is looking at how these changes correlate to glucose management as measured by fasting blood sugar, hemoglobin A1c and the “time in range” (glucose readings between 70 mg/dL and 180 mg/dL).
The OCT-A is a noninvasive test that will be available in the large and broadly distributed network of primary care optometry offices across the country. The scan is not a one-time screening but requires multiple testing, interruption and correlation with best-corrected visual acuity. This scan may also be important to patients who are not diagnosed with diabetes but may have borderline HA1c tests or metabolic syndrome or even as a measure of vascular health in hypertension and dyslipidemia.
Optometrists who have expanded their knowledge in systemic disease as well as the use of OCT technology are well poised for a much greater role in the prevention, diagnosis and management of chronic medical problems. Just as this technology moved our profession into a major role in the prevention of blindness from glaucoma, the latest version of this technology will shift us into a major role in prevention of pain, suffering, loss of function and shortened life spans related to chronic systemic medical problems.
With Vision Expo West coming later this month, take a course or two on systemic medical problems and reading and understanding the OCT. Then go to the exhibit hall and look at this technology. The future belongs to those willing to change with the times.
Alibhai AY, et al. Retina. 2018;doi.org/10.1016/j.oret.2017.09.011.
Tang FY, et al. Nature. 2017;7:2575.