Normal Retina

Abnormal growth of blood vessels with fluid on OCT from Age-related macular degeneration

DRY & WET MACULAR DEGENERATION:
The dry form (non-exudative AMD) which accounts for the majority of cases of AMD is slowly progressive. Unfortunately, patients with dry AMD may progress to the more rapidly progressive wet AMD and ultimately experience rapid loss of central vision leading to legal blindness.

HARDENING OF THE ARTERIES IN THE EYE:
Simply speaking, macular degeneration is hardening of the arteries (arterio-sclerosis) in the eye. The same basic aging process that causes heart disease, peripheral vascular disease, carotid disease and cerebral vascular disease causes macular degeneration.

The same fundamental process that causes heart attacks and strokes can also cause blindness from macular degeneration. Bad circulation in the heart can cause a coronary thrombosis (heart attack); bad circulation in the brain can cause a cerebral thrombosis (stroke); bad circulation in the neck can also cause strokes; bad circulation in the legs can result in amputation; and bad circulation in the eye can cause blindness from macular degeneration. Patients with any of these age-related circulatory conditions are prone to developing other circulation problems. As a result, heart attack and stroke patients should also be concerned about their eyes.

THE CAUSE OF THE VISION LOSS:
After blood flow has been interrupted by a blood clot or blockage due to bad circulation, the body inappropriately responds to this injury by producing abnormal blood vessels. These abnormal blood vessels (choroidal neo-vascularization) are not “healthy”. They are extremely fragile and leak fluid and blood into the delicate retinal tissues. This results in irreversible damage to the retinal tissues, which are now denied their normal healthy blood flow and nutrition. It is these delicate retinal nerve fibers that transmit the visual signals to the brain. As such, any damage to these tissues caused by the interruption of normal circulation will result in irreversible loss of vision in this area. Unfortunately this damage most commonly occurs in the very center or the retina called the macula, and results in the loss of central vision. It is our central vision that allows us to read, watch TV, play bingo, see our computer, etc. Although the macula represents less than 5% of our entire retina, it accounts for more than 95% of the visual function (e.g., reading, writing, computer, TV, driving etc.).

PAST TREATMENT OPTIONS:
Argon Laser:
In the past, all that could be done to treat the abnormal blood vessels that developed in macular degeneration was to destroy them with the Argon laser. Although this treatment was able to stop the spreading growth of the abnormal blood vessels, of necessity, it also had to destroy the never fibers in the area. As a result, in order to retard the progression of the disease, the Argon treatment also resulted in damage to the retina. Vision therefore was not improved.

Visudyne:
About four years ago, photodynamic therapy (PDT) using an injectable material called Visudyne was introduced to treat the leaking blood vessels of wet macular degeneration. The Visudyne was injected into the patient’s veins and as it circulated through the retina, the doctor would use a laser to “zap” the laser-sensitive molecule as it passed through the leaky blood vessels. This was more precise than the Argon laser because it only treated the areas of bad circulation and therefore was much gentler on the retinal nerve fibers. PDT however required multiple re-treatments and was still a “destructive” procedure. More importantly it did not get to the underlying mechanism of the progression of AMD, i.e., the growth of abnormal blood vessels. Something was needed that could retard the growth of abnormal vessels without causing localized damage to surrounding tissues. Something was needed to get at the underlying mechanism of abnormal blood vessel proliferation.

Lucentis:
The answer to preventing the spread of abnormal leaky blood vessels following strokes, heart attacks and wet macular degeneration would not come from the circulation doctors or the retinal doctors, but from the cancer doctors. They had discovered that tumors grew rapidly because of a compound they named “vascular endothelial growth factor (VEGF)”. They next developed medicines that could destroy VEGF, thereby halting the expansion and growth of the tumors. Basic scientists soon recognized the potential of this new class of medicines in the treatment of the circulatory disease associated with the same rapid growth of bad blood vessels seen in tumor growth. Now there was a way to get at the fundamental cause of vascular growth after strokes, including the growth of blood vessels characteristic of wet macular degeneration. Lucentis is the “descendent” of these cancer treatment medications and has been adapted specifically for use in the eye.

HOW IS AMD DIAGNOSED?
Macular degeneration can only be diagnosed effectively by dilating the pupil of the eye and examining the retina. If suspicious areas are identified, they are studied more carefully with tests like Fluorescein Angiography and computer imaging. Fluorescein Angiography is an angiogram of the eye and is totally analogous to a coronary angiogram which is performed to evaluate heart circulation prior to angioplasty or by-pass surgery. If these tests show “active” abnormal retinal circulation, then Lucentis is possible.

Choroidal Neovacularization with Hemorrhage Abnormal growth of blood vessels with bleeding in AMD.

HOW IS LUCENTIS TREATMENT PERFORMED?
The eyeball is numbed with an anesthetic (Xylocane) placed on a simple sterile Q-tip and held on the eye for a few seconds. Once numb, a small amount of Lucentis is introduced by injection into the vitreous of the eye. That’s it! There is virtually no pain. Not only can this small injection slow-down and ultimately stop the expansion of the abnormal circulation, it can actually reverse damaged nerve tissue if it is done in time.

FOLLOW-UP
Since the damage following the growth of abnormal retinal blood vessels (wet macular degeneration) can be progressive, close follow-up is necessary. Repeat Fluorescein Angiograms, computer imaging and repeat Lucentis treatments are necessary until the damage has been corrected.

Dr. Claudio Ferreira of Eye Health Vision Centers participated in the clinical trials of an earlier version of Lucentis called Avastin while working as a Clinical Instructor of Ophthalmology at the University of Virginia in 2004. Avastin, which had been used for the past three years by ophthalmologists on a trial basis, has only this year been replaced by it’s “new and improved” descendent, Lucentis. Lucentis consists of smaller molecules which provide better retinal penetration but with the same mechanism of action.

Dr. Ferreira converted to Lucentis immediately upon its FDA approval in June, 2006. Coincident with the FDA approval of Lucentis, Dr. Ferreira assumed the position of retinal specialist at Eye Health Vision Centers in Dartmouth. Dr. Ferreira reported that he was delighted to be the first retinal surgeon to offer Lucentis to the patients of Southeastern Massachusetts and states that the majority of his patients have already had their vision stabilized, and a significant number have had their vision actually improve. This treatment represents a significant advancement, as improvement of vision in patients with wet macular degeneration was almost unheard of prior to the discovery of Avastin and Lucentis.

According to Dr. Ferreira there is no standard therapeutic protocol for Lucentis. Each patient responds differently to the drug. The therapy needs to be individualized according to each patient’s clinical response. The procedure is rather simple and completely painless. Side effects are minimal and the risks are the same as with other intraocular injections”.

At Eye Health Vision Centers, Dr. Ferreira has the advantage of having state-of- the-art technology for the evaluation and treatment of AMD including Optical Coherence Tomography (OCT) and Digital Fluorescein Angiography.