What’s an eye and orbit ultrasound?
An eye and orbit ultrasound uses high-frequency sound waves to measure and produce detailed images of your eye and eye orbit (the socket in your skull that holds your eye).
This test provides a much more detailed view of the inside of your eye than a routine eye exam.
An ultrasound technician or an ophthalmologist (a doctor who specializes in diagnosing and treating eye disorders and diseases) usually performs the procedure (sometimes called eye studies).
Eye studies can be done in an office, outpatient imaging center, or hospital.
Your eye doctor may order eye studies if you’re experiencing unexplained problems with your eyes or if you’ve recently sustained an injury or trauma to the eye area.
This procedure is helpful in identifying issues with the eyes as well as diagnosing eye diseases. Some of the issues the test can help identify include:
An eye and orbit ultrasound can also be used to help diagnose or monitor:
- glaucoma (a progressive disease that can lead to vision loss)
- cataracts (cloudy areas in the lens)
- lens implants (plastic lenses implanted in the eye after the natural lens has been removed, usually due to cataracts)
Your doctor can also use this procedure to measure the thickness and extent of a cancerous tumor and to determine treatment options.
An eye and orbit ultrasound requires no specific preparation.
No pain is associated with the procedure. Anesthetic drops will be used to numb your eye and minimize discomfort.
Your pupils won’t be dilated, but your vision may be temporarily blurred during the test. You should be able to drive 30 minutes after the procedure, although you may feel more comfortable arranging for someone else to drive.
Your eye doctor will advise you not to rub your eyes until the anesthetic has completely worn off. That’s to protect you from unknowingly scratching your cornea.
There are two parts to an eye and orbit ultrasound. The A-scan ultrasound takes measurements of your eye. The B-scan allows the doctor to see the structures in the back of your eye.
The combined procedure (A and B scans) will take 15 to 30 minutes to complete.
The A-scan measures the eye. This helps determine the correct lens implant for cataract surgery.
While sitting upright in a chair, you’ll place your chin on a chin rest and look straight ahead. An oiled probe will be placed against the front portion of your eye as it’s scanned.
An A-scan can also be performed while you’re lying down. In that case, a fluid-filled cup, or water bath, is placed against the surface of your eye as it’s scanned.
The B-scan helps your doctor see the space behind the eye. Cataracts and other conditions make it difficult to see the back of the eye. The B-scan also helps in the diagnosis of tumors, retinal detachment, and other conditions.
During a B-scan, you’ll be sitting with your eyes closed. Your eye doctor will put a gel on your eyelids. They’ll tell you to keep your eyes closed while you move your eyeballs in many directions. Your eye doctor will place the probe against your eyelids.
This is a quick and painless procedure with no serious side effects or risks.
Your ophthalmologist will review the results with you.
Your doctor will make sure the measurements of your eye taken from the A-scan are within the normal range.
The B-scan will give your doctor structural information about your eye. If results are abnormal, your doctor will need to determine the cause.
Some conditions that might be revealed by the B-scan include:
- foreign bodies in the eye
- detachment of the retina
- damaged tissue or injury to the eye socket (orbit)
- vitreous hemorrhage (bleeding into the clear gel, called the vitreous humor, that fills the back of the eye)
- cancer of the retina, under the retina, or in other parts of the eye
Once your doctor reaches a diagnosis, they will work to determine the best course of treatment for you.