Neuro-Ophthalmology is a subspecialty of ophthalmology that examines the relationship between the eye and the brain, focusing on the optic nerve, orbit and brain. Neuro-ophthalmic diseases include optic neuritis, ischemic and compressive optic neuropathy, ophthalmic migraines, cerebrovascular disorders, pituitary adenomas, pseudo-tumor cerebri and many others. Symptoms associated with these disorders usually include vision loss, vision disturbances, double vision and eyelid disorders. Sudden vision loss can be caused by tumors or aneurysms that require immediate treatment. Lack of blood flow to these sensitive parts of the eye can result in irreversible vision loss if not treated appropriately. Neuro-ophthalmic conditions are often the first sign of a more serious systemic neurologic condition and thus must be recognized and treated immediately.
Dr. Lee Shettle spent a year of subspecialty training in Neuro-Ophthalmology to diagnose and treat eye related neurologic disorders at Michigan State University. Diagnostic services often include fundus photography, MRI, CT scans, vascular ultrasounds, hematologic and cerebral angiography. Neuro-ophthalmic examinations require very detailed history and examination-taking skills, which can take much longer than your routine eye exam. During the exam Dr. Shettle will exam your visual pathway, visual fields, eye movements and other associated neurologic testing as indicated. The inter-relationship between the eye and the brain is very complex which is usually best treated by a physician such as Dr. Shettle with extra training in this field of medicine.
Ophthalmic Electrophysiology Testing
Diopsys® NOVA Vision Testing System
The Diopsys® NOVA Vision Testing System provides your doctor with painless, non-invasive vision tests that utilize electrophysiological technology, including Visual Evoked Potential (VEP) and pattern Electroretinography (ERG).
The purpose of these tests is to provide comprehensive information to assist your doctor in better planning your treatment (if needed) and monitoring the results.
Visual Evoked Potential (VEP)
Visual Evoked Potential (VEP) measures the electrical activity in the vision system. When light from an image enters your eye, it is converted into electrical energy at the retina and travels through the optic nerve to the visual cortex of the brain which processes vision. The Diopsys® NOVA-VEP test measures the strength of the signal reaching your visual cortex and how fast it gets there.
The VEP technology in the Diopsys® NOVA device helps determine how your eyes communicate with your brain in a way that no other instrument or vision test can.
Pattern Electroretinography (ERG)
Pattern Electroretinography (ERG) measures the function of your retina – the light-sensitive layer at the back of your eye. When light from an image enters the eye, it is converted into electrical energy by specialized cells in the retina. These cells send electrical impulses through the optic nerve to the brain where the image is processed. The Diopsys® NOVA-ERG test records how well the cells of the retina are conveying electrical impulses within the eye.
ERG results have been demonstrated to aid in the diagnosis and treatment planning of many vision disorders.