Retinal Imaging: What's An OCT Scan And Why Is It Important?
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If you've completed a comprehensive eye exam in the past, or have recently visited your optometrist, then they may have recommended taking retinal photos during your checkup.
Just like most people you may be wondering what retinal photos are and why you would opt-in for the added cost to your exam.
I mean, what's the point of paying more than you need to. Right?
Just because your vision is clear or your eyes 'feel' as though they're fine, it doesn't necessarily mean that your eyes are healthy.
The truth is, there are a number of ocular diseases and conditions that can creep up on you without any significant symptoms ever arising.
This puts you at risk of leaving underlying eye health issues unattended potentially causing greater harm to your eyes. Neglecting to address any issues with your eyes could limit your treatment options or decrease the likelihood of successful treatment.
So, what are retinal photos?
In short, retinal photos are high-quality images of the back of the eye that allows your optometrist or eye doctor to conduct a retinal exam and determine the health of your eyes in great detail.
To be fair, most eye exams will include some form of retinal examination.
However, what your doctor can see using traditional methods pale in comparison to the high-resolution images taken from the retinal photos.
If you're still unsure, that's OK.
This article will break down everything you need to know about retinal exams. Including digital retinal imaging, Optical Coherence Tomography (OCT) scans, what to expect in the exam, and why it's important to incorporate in your eye health routine.
What Is Digital Retinal Imaging?
Digital retinal imaging is the process of taking a digital, high-resolution image of your retina located in the back of your eye.
In the past, your optometrist or eye doctor would administer special eye drops to dilate your pupils. They would then look into your eye, specifically the retina, using instruments like a slit lamp with magnifying lenses or an ophthalmoscope.
Now, with digital retinal imaging, the latest technology gives your optometrist or eye doctor a high-quality, digital image of the inside of the eye and all of its internal structures.
This image is then used to study and track the overall health of the retina, the optic nerve, and other internal structures. They are then saved into your medical record to compare results from previous years.
What Is An OCT Scan?
An Optical Coherence Tomography (OCT) scan is another method of retinal imaging. The OCT scan is the latest advancement in non-invasive imaging technology.
The process is similar to an ultrasound but instead of using sound to create images, an OCT scan uses light waves to create a high-resolution image of the structural layers inside the eye.
The procedure involves using a low-powered laser, called a scanning laser, that scans the internal structures of the eye.
This technique of retinal imaging creates a three-dimensional scan of the retina at extremely high resolutions. The image captured displays a cross-section of the eye and is able to show each of the retina’s distinct layers.
The images are then analyzed by your optometrist or eye doctor for monitoring the overall health of the eye and to identify any abnormalities should they arise.
The assessment and the images are stored in your medical record to compare the condition of your retina year-over-year.
Apart from monitoring the overall health of your eyes, the optometrist or eye doctor can detect and manage a range of ocular conditions including:
Age-Related Macular Degeneration (AMD/ARMD)
This is usually signified by fluid leaking or bleeding at the back of the eye.
A dark spot at the back of the eye could be a sign of melanoma. Early detection allows for early treatment which may prevent or slow down serious damage and/or cancer spreading to the rest of your body.
Diabetes can cause changes in the blood vessels of the retina, such as swelling, leaking, or the creation of new blood vessels. Blindness is a major concern if left untreated
Unusual pressure against the optic nerve and the compression of blood vessels in the eye could be an early warning sign of glaucoma.
High Blood Pressure
Signs of high blood pressure often first appear in the eye. Indicators could be narrowing of the blood vessels, spots on the retina, or bleeding at the back of the eye.
A retinal exam can spot early signs of the retina lifting or pull away from the wall of the eye before it causes significant damage to your eye health and vision.
What To Expect For An OCT Scan
During the Exam
Depending on the instruments available at your doctor's office, you may have your pupils dilated to begin the procedure. Other instruments do not require pupil dilation and this step may be skipped.
The dilation widens your pupils before the examination and typically takes about 20 minutes to take effect.
When your pupils have dilated enough for the OCT scan, you are sat down in front of the medical instrument and begin by resting your chin and forehead for the procedure.
You will be asked to stare straight ahead into the machine with your gaze fixed to an object while the scanning laser begins to scan your eye.
The image is then rendered and uploaded to the computer for the doctor to begin their analysis. The procedure is relatively quick and takes about five minutes after the dilation.
After the Exam
The procedure is quick and the results will be ready immediately after. The optometrist or eye doctor will report their assessment and let you know how your eyes have progressed since the previous exam.
Be mindful and plan ahead if you have to get your eyes dilated for the OCT scan. The effects of the dilation will remain for about 4 hours following your exam.
During this time your vision will be blurry and your eyes will be extremely sensitive to light as your pupils are wide open.
It's recommended to bring sunglasses for after your exam and to make sure you bring a friend or someone to drive you home afterwards.
- The procedure is fast, painless, and you will have results immediately after the exam.
- An OCT scan allows your optometrist or eye doctor to see ocular conditions or diseases they would not be able to see with traditional methods.
- Keeps you mindful of the health of your eyes and lets you know if something's gone wrong at the earliest stage.
- It creates a baseline for your eye health and your optometrist can track and compare results from previous years.
The Importance of Retinal Imaging
1. Early Detection
Early detection can reduce the risk of serious damage or implications to the health of your eyes.
The first signs of ocular issues are seen in the retina. Retinal imaging allows your optometrist or eye doctor to detect any irregularities or deficiencies at the earliest stage
2. Tracking and Information Storage
The data is easily stored in a database that can be recalled for future assessments. This gives your optometrist or eye doctor a year-over-year comparison of the health of your eyes.
3. Health Indicator
Assessing the health of the retina not only promotes overall eye health but it can also identify other potential health concerns unrelated to ocular health.
Unusual or sudden changes to the retina are early warning signs to major health conditions such as cancer, diabetes, and high blood pressure.