B-scan ultrasonography, or B-scan, is a diagnostic test used in optometry and ophthalmology to produce a two-dimensional, cross-sectional view of the eye and the orbit.
The ultrasound uses high-frequency sound waves that travel through the eye. Reflections (echoes) of the sound waves form a picture of the structure of the eye.
You will be seated or lied down. The test is usually done with your eyes closed. A gel is placed on the skin of your eyelids. The B-scan probe is gently placed against your eyelids to do the test. You may be asked to look in many directions to improve the ultrasound image or so it can view different areas of your eye.
B-scan is done to look at the inside part of the eye or the space behind the eye that can’t be seen. This may occur when you have matured cataracts or other conditions that make it hard for the doctor to see the retina. The test may help diagnose retinal detachment, tumors, or other disorders.
The B scan Eye test is done to get an idea of the back portion of the eye. The back portion of the eye consists of the area behind the lens of the eye. Mainly the vitreous gel and the retina.
One of the most common reasons to perform this test is before cataract surgery. If the cataract is very advanced it blocks the view of the retina. In that situation, your doctor does not know the status of your retinal health. The ultrasound helps us here. We get to know if the retina is in its position and if there is something grossly wrong with the retina.
There are a few other conditions also when the B Scan eye test is done. In patients who have an advanced thyroid eye disease, this test is done to see the position of the muscles of the eye. Sometimes when the eye protrudes out, again an ultrasound helps. We come to know if there is any space-occupying lesion behind the eye that is pushing the eye outwards.