Detecting the Earliest Signs of Retinal Disorders Has Just Gotten Easier with Telemedicine
How does Fundus Photography work?
A camera that focuses on the retina at the back of the eye is used to record a picture of the vessels and surrounding tissue. This camera can be used by a technician or nurse at your primary care physician's office, and does not ordinarily require the patient to use eyedrops to dilate the eye. A low-intensity flash is used to illuminate the back of the eye in order to record the image. This picture is then sent to a retinal specialist trained in diagnosing and evaluating diseases that affect the retina. This specialist will note if anything appears to be abnormal in either eye, and record these findings in a report that is sent back to your primary care physician. Your physician will then discuss the findings with you.
Some of the cameras that are used in fundus photography include the CenterVue DRS and the Nidek AFC. You can click on the images in the sidebar on the right-hand side of this page. The links will take you to a youtube video that shows how the camera is used.
LEFT: An example of a fundus photograph of the central retina. The dark region in the center is the location of the center of your visual field where vision is most sharp. The white spot on the right is the optic disk where blood vessels enter the eye and where visual signals are sent to the brain along the optic nerve.
What are some of the eye disorders that can be screened by fundus photography?
The conditions that can be detected by fundus photography include both rare disorders, as well as more common ones. Some of the most common retinal disorders that are screened include diabetic retinopathy, age-related macular degeneration, and glaucoma. Photographic screening for such diseases has been shown to be simple and effective. Certainly if you have other health concerns that have already been diagnosed, fundus photography becomes a very important test because it allows the physician to determine if the disease has advanced and is affecting your vision. For example, patients with diabetes should be tested on a regular basis for early signs of diabetic retinopathy, while patients with a familiy history of macular degeneration or glaucoma should be tested regularly for early signs of these diseases.
What is Diabetic Retinopathy?
The retina is the light-sensitive tissue at the back of the eye, and is necessary for good vision. Under normal conditions, the retina is supplied with nutrients and oxygen from tiny blood vessels passing within and across the retina. Diabetic retinopathy causes these blood vessels to break open and leak blood and fluid into the retina. This fluid causes the retina to swell and thicken (edema).
The swelling of the retina distorts its shape, which then distorts the visual image that is sent to the brain. In addition to the visual distortion, there may also be areas of missing vision (scotomas). In some people, diabetic retinopathy may also involve the growth of abnormal new blood vessels across the surface of the retina, which leads to a significant loss of vision. Diabetic retinopathy usually affects both eyes, but it is possible to have one eye with more or less damage than the other. This is why it is important to evaluate both eyes for signs of the disease.
Diabetic retinopathy is a disease that can be defined by stages of increasing damage and worsening vision. If you have recently acquired diabetic retinopathy, you may not notice any immediate changes to your vision, but over time, diabetic retinopathy tends to worsen and results in significant vision loss or even functional blindness.
Can Diabetic Retinopathy be prevented?
Diabetic retinopathy is best controlled by keeping diabetes itself under control. This means careful and regular monitoring of your blood glucose level to see if this is under control. In addition, there are many things you can do to improve your overall health and reduce the likelihood of developing diabetic retinopathy, such as not smoking, maintaining normal weight, and getting regular exercise. Proper diet and the availability of nutrients for tissue repair are important for maintaining your existing vision and slowing the overall progression of the disease. You should discuss preventative measures with your doctor if you have not already had this discussion.
Is Diabetic Retinoapthy treatable?
To some extent, diabetic retinopathy is treatable, but there are usually limits to the effectiveness of such treatments. In addition, treating the disease does not necessarily restore lost vision, but is a means to help maintain the vision that still remains. Treatments may consist of lasers to stop the bleeding and spread of vessel growth, as well as injections into the eye to reverse or limit edema. While there are remarkable advances being made in treating the disease, it is clear that preventing the disease is the best option for keeping your current vision. Regular fundus photography for evaluating retinal change is an important part of prevention and assessing the effectiveness of treatments.
Why is regular Diabetic Retinopathy screening so important?
Regular examination of your eye's retinas allows a trained eye care professional to determine if the signs of diabetic retinopathy exist. If there are signs of the disease, these can then be graded to determine the level of diabetic retinopathy that exists. By comparing examinations from different points in time, the doctor can determine whether the diabetic retinopathy is worsening or if it is stable and under control. The use of fundus photography allows for a permanent record of your eyes on a given date, plus it makes the evaluation of your eyes more convenient for both you at the doctor.
