Category Archives: Retina

New Technology at Total Eye Care Predicts Glaucomatous Vision Loss

Pattern Electroretinography (PERG) Gives up to 8 Years of Advanced Warning

NOVA-ERGDeviceIncorporating the most advanced technology available in caring for our patients is important to the way we practice at Total Eye Care. The Diopsys® Pattern Electroretinograph is the newest addition to our suite of technology. The Pattern ERG (PERG) measures the signal strength of the retinal information being sent to the optic nerve. Studies show that a 10% decrease in this signal can be detected up to 8 years earlier than a 10% loss of nerve fibers detected by the scanning laser ophthalmoscope or optical coherence tomographer, thus allowing for a much earlier diagnosis and treatment.

Early detection and treatment of glaucoma is important due to the fact that nerve tissue cannot be regenerated. Twenty years ago, in the absence of a very high intra-ocular pressure, it was a common practice to wait until a visual field defect was present before initiating treatment. There is a significant amount of redundancy in the retinal nerve fibers, thus studies have shown that a patient must lose approximately 50% of the nerve fibers serving a given section before the loss of nerve fibers result in a detectable visual field defect. The scanning laser ophthalmoscopes changed all of that allowing us to detect earlier, more subtle changes in the retinal nerve fiber layer. Now patients are treated before visual field defects become apparent.

The Diopsys® Pattern Electroretinograph is the next step in early detection. The PERG will not replace the scanning laser ophthalmoscopes such as the Zeiss Cirrus Optical Coherence Tomographer (OCT) in the diagnosis of glaucoma; however, it gives us another valuable tool in the diagnosis and treatment of glaucoma.

FDA Approves First Bionic Eye

The FDA approved Second Sight’s “bionic” eye. While actually more of a retinal prosthesis, the implant is designed to assist patients with retinitis pigmentosa. The Argus II Retinal Prosthesis System has a resolution of 60 pixels. The device will not provide the HD type of vision that our eyes are capable of; however, more importantly, this technology will greatly aid a blind patient’s mobility and is a revolutionary step forward.

The system consists of a wireless retinal implant that rests on the retina. The patient will wear special glasses that see the image. The image will be sent to a visual processing unit that is worn on the patient’s hip. Once the data is processed it is sent back to the glasses which wirelessly transmit this data to the retinal implant. The implant electrically stimulates the photoreceptors simulating a coarse image. The patient learns how to interpret these light and dark images allowing them to navigate around and among obstacles.

The device was approved for use in Europe last year. Check out the video below from the European branch of the medical device company.

Say It With Your Eyes This Valentine’s Day

Some say the eyes are the window to your soul, but did you know they are also a window to your overall health?  Signs of high blood pressure and other conditions which can indicate an increased risk of heart disease and stroke can be seen with an eye exam.

 As February is American Heart Month, Drs. Richard Driscoll and Alycia Green of Total Eye Care are encouraging residents of Keller and Colleyville to take this opportunity to protect their vision and heart health by having an eye exam and an optomap retinal exam.

Dr. Driscoll comments: “Cardiovascular disease is the leading cause of death in the United States; one in every three deaths is from heart disease and stroke, equal to 2,200 deaths per day.”*

Most people don’t realize that by visiting their optometrist for an eye examination, and in particular by having a simple optomap,  signs of hypertension can be detected, which if left untreated, can lead to heart problems and stroke.

An optomap is one of the most advanced technologies in eye care technology. It is the only technology currently available that provides an ultra-wide 82% view of the retina (the back of the eye) in one image – including the all-important periphery for successful diagnostics of both eye and non-eye related conditions and diseases.

“Viewing the retina during an eye examination allows  me to see the retinal blood vessels and detect any changes to their size and pattern,” Says Dr. Green. “Such changes can be indicative of changes in blood vessels in other parts of the body, such as the heart, and they highlight that further medical investigation and treatment may be required.”

To book an eye examination and optomap call 817.416.0333 or schedule an appointment online.

For more details on American Heart Month 2013 and further information about heart disease visit the Centers for Disease Control and Prevention – www.cdc.gov/features/heartmonth/

* Source: www.cdc.gov/features/heartmonth/ (online, 2013)

Visual Evoked Potential – New Technology Available at Total Eye Care

We have added a new service here at Total Eye Care. It is called the Visual Evoked Potential or VEP. Until recently this technology was only available to large institutions and teach hospitals. We are now able to provide this service for our patients at the Colleyville office.

What is the VEP?

The VEP, or Visual Evoked Potential, measures how well you visual system is working. Testing the integrity of your visual system is done by showing you a series of checkerboard patterns and then measuring the electrical activity between your eye and the visual cortex of your brain.

Your eye converts what you see into very low voltage electrical signals that travel along the optic nerve between your eye and the visual cortex. The computer inside the VEP compares the strength and speed of signal to a database of normal results and then the doctor uses that information to guide his or her diagnosis.

How is the VEP Done?

Two sticky pieces of tape are placed on your forehead and another on the back of your head. A patch is then placed over one eye and you look at a computer monitor that shows you the checkerboard pattern. When the testing is complete the process is reversed for the other eye. That’s all there is to it.

What Does the VEP Tell the Doctor?

The VEP evaluates how well the entire visual system is working. A visual field (peripheral vision test) gives the doctor similar information. In this way the VEP  helps the doctor diagnose and manage patients with glaucoma. The VEP is also used in the diagnosis and treatment of patients with amblyopia, multiple sclerosis, myasthenia gravis, optic atrophy, and concussion to name a few.

Doc, What Do Floaters Look Like

Today was floater day in the office. The most common questions today were all about floaters. The questions were centered around what do they look like, how do they start and what causes them. Not long ago I published in The Eye Doc blog an article about floaters but sometimes a picture is worth a thousand words. While researching for a future article I came across a very realistic video that does a good job simulating what floaters look like. By the way, most people have some floaters but not everyone has seen their floaters (and some people wish they had never seen their floaters).

If you want to see your floaters look up at the sky on an overcast day or at an evenly illuminated wall and you will most likely see those wispy cobwebs float by your vision. Check out the video below for a good representation of what a floater looks like. Most people don’t have as many floaters as is shown in the video but you’ll get the idea. If you want to learn more about floaters check out these articles I’ve written about them.

Retinal Photos May Aid in Detection of Alzheimer’s Disease

It is often said that the eye is the window to one’s soul, early data suggests that retinal photos may become that window used as an early detector of Alzheimer’s disease. The preliminary results of an Australian pilot study were unveiled in Paris yesterday at the International Conference on Alzheimer’s Disease. Not many details were released however it appears that retinal photographs were used to determine the ratio of the diameter of the retinal arteries to the retinal veins (called the A/V ratio). The investigators then found a positive correlation between the A/V ratio and the amount of beta amyloid deposits in the brain. Beta amyloid deposit or plaques are known to exist in higher concentrations in patients with Alzheimer’s disease.

If further study of this correlation confirms the author’s findings then this could lead to an inexpensive and relatively easy way of giving patients and doctors  an early indicator of which patients are more likely to later develop Alzheimer’s Disease.

Total Eye Care to Conduct Fundus Vascular Abnormalities Study

We are very pleased to announce that Total Eye Care will start its first clinical study next month. The title of the study is Vascular Fundus Changes in Patients With High Probability of Chronic Cerebrospinal Venous Insufficiency. Check out the video below for more information. We are recruiting patients with either Ehlers-Danlos Syndrome or Multiple Sclerosis so please spread the word. The video has a lot of good information on the study so please do check it out.