What is Neuro-Ophthalmology?
Neuro-ophthalmology is an ophthalmic subspecialty
that addresses the relationship between the eye and the brain,
specifically disorders of the optic nerve, orbit, and brain, associated
with visual symptoms. It provides comprehensive
clinical care to a broad spectrum of patients with visual disturbance
from optic nerve diseases, central nervous system disorders, ocular
motility dysfunction, and pupillary abnormalities. Over 50 percent of
all intracranial lesions involve the visual or oculomotor pathways.
This is the most common cause of sudden decreased
vision in patients older than 40 years. We do not see with our eyes. We
see with part of our brain that is capable of interpreting visual
signals sent back from the eyes. This is located at the back of our head
(the occipital lobes). Information is transmitted from the eyes to the
brain via the optic nerves. These nerves are composed of the long tube
extensions (axons) of cells (ganglion cells) located within the inner
lining of the eye (the retina) that exit the back of the eye at the
optic disc. Each of the optic nerves receives blood supply from branches
of the ophthalmic artery within each eye socket. The optic disc has a
unique blood supply (the posterior ciliary arteries).
Loss of blood supply within the posterior ciliary arteries deprives the optic nerve tissue of oxygen and results in damage to parts or all of the optic nerve. This is a small stroke in the optic nerve. It is painless. Patients may become aware of decreased vision or difficulty seeing above or below the center of gaze. Loss of the blood supply results in swelling of the optic disc, often associated with hemorrhages. The hemorrhages, and swelling will go away leading to the development of a pale disc (optic atrophy). As the swelling resolves, some of the axons will be permanently lost. We do know that this happens more often in patients who are born with small optic discs. These episodes may occur when there is a sudden drop in blood pressure (following an operation or associated with blood loss after an accident). Patients who smoke, or who have diabetes or high blood pressure, may be at higher risk for AION.
What to Expect During Your Visit:
- A physician referral is required to schedule your appointment.
- Information from your referring doctor provides crucial information and prevents unnecessary repetition of testing.
- Bring images (on disk or film) of all recent brain MRI or CT scans for review.
- Your pupils will be dilated to allow comprehensive examination.
- You may be in the office for 4-6 hours so that doctors can review your case and scans and obtain diagnostic testing.
- You may be sent for more blood work/neuroimaging to aid the diagnosis.
- For scan results, patients should call the office the day after the scan was ordered.