Pattern Electroretinography (PERG) Gives up to 8 Years of Advanced Warning
Incorporating 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.
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.
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)
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.
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.
New technology now available at Total Eye Care allows us to scan a patient’s retina for glaucoma and macular degeneration, and the best part ….. it does it WITHOUT DILATION! This new instrument is called the Zeiss Cirrus OCT and it is truly state of the art.
The Zeiss OCT uses infra-red light from a scanning laser to make a very high resolution, 3D image of the inside of your eye, much like that of an MRI. We can now identify retinal objects as small as 4 microns. So how small is 4 microns? A single sheet of 20 lb copy paper is 100 microns thick. This new technology allows us to detect glaucoma and macular degeneration much earlier as well as allowing us to detect and track subtle retinal changes.
Who is a candidate for this new technology? Anyone with a family or personal history of glaucoma, glaucoma suspect or macular degeneration should take advantage of this technology.
Call the Colleyville office at 817.416.0333 and let Rona or Kelsey know that you would like to take advantage of the new scanning laser technology right away.
WFAA TV in Dallas produced a good video on the optomap® Retinal Exam technology. WordPress won’t allow it to be embedded here, however I’ve added it to the optomap® page on the Total Eye Care Website. An optomap® video from the TV show The Doctors can also be found there.