New advancements in devices and technology are constantly improving our ability to more accurately diagnose issues and prescribe appropriate treatment. The following devices are a few that I have found especially beneficial in regards to early diagnosis and treatment.
OCT allows for early detection and diagnosis in numerous pathologies, including retinal edema or atrophy, retinal pigment epithelium and choroid, macular degeneration, diabetic retinopathy and glaucoma. Recent software allows for the detection of glaucomatous damage through analysis of the macular region. The ability this affords to obtain detailed retinal ganglion cell (RGC) analyses is especially useful in determining the presence and progression of disease vs. scanning the optic nerve, which has natural variations depending on the patient population being tested. In prior years, it was not uncommon for me to perform OCT testing and receive normal results only to perform a RGC analysis and detect early disease. The ability to obtain the most accurate information upfront is invaluable in providing the best possible care for my patients.
The Diopsys Nova ERG and VEP vision testing system is another device that can help detect and manage a variety of ocular conditions. While electrophysiological tests are not new, technological advancements have made it possible to conveniently perform them within the office setting. Utilizing comfortably placed sensor pads and a computer screen that shows the patients varying black and white patterns, all the patients need to do is watch.
Similar to OCT, pattern electroretinography (PERG) tests the retinal ganglion cells but objectively analyzes function instead of structure. This diagnostic is useful for multiple maculopathies, including diabetic retinopathies, Plaquenil toxicity and macular degeneration, and is significantly valuable in the early detection of glaucoma. Recording the response of electrically active retinal ganglion cells to a stronger or weaker stimulus can aid in determining the state of disease present, allowing PERG to detect early glaucoma much earlier than traditional testing.
Visual evoked potentials can be performed by the Nova to help determine subjective field loss by measuring the electrical activity of the visual cortex. The strength of the signal is measured as amplitude while the latency denotes the length of time the signal takes to travel from the retina to the visual cortex. Through this, we can better understand the health of the entire visual pathway and intervene before irreparable damage occurs. This test is useful in detecting possible ocular damage, optic nerve impairment, and conditions such as optic neuritis and amblyopia.