What is an ocular ecography?
The ocular ecography, ultrasonography or ocular ultrasound is an imaging test. It can show the inside of the eye, even if the opacity of media does not allow its visualization and can also represent parts of the orbit and the tissues around the eye.
Ecography uses ultrasound to obtain the image of the ocular structure. It is a sound of very high frequency, imperceptible to the human ear and absolutely innocuous. For this reason, the ecography (in its adapted version) is the test of choice in obstetrics. The structures that can be seen with an ultrasound could only be assessed with other imaging tests, such as radiography, CT or MRI, which are more laborious, partially aggressive due to the use of radiation or require the application of intravenous contrasts
What types of ocular ultrasound exist?
There are several types of ocular ultrasound: ultrasound A or A-Scan, ultrasound B or B-Scan and UBM or ultrabiomicroscopy. Each one of them has its particularities.
- Ultrasound A, A-Scan or one-dimensional ultrasound
It is used to measure the size of eye structures and calculate the power of the intraocular lens needed in cataract surgery.
- Ultrasound B, B-Scan or two-dimensional ultrasound
It is used to obtain images and videos of the inside of the eye and the orbit. We need it to assess the inside of the eye in case of opacity of optical media (due to corneal opacity, vitreous hemorrhage or advanced cataract), to assess the texture of the interior of ocular tumors for differential diagnosis or to look for foreign bodies after or eye injuries
- UBM or ultrabiomicroscopy
It is a high frequency ultrasound and is used to obtain images of the anterior segment of the eyeball. Obtains high definition images that are necessary to assess patients with glaucoma, tumors, eye injuries and before implantation of phakic lenses in refractive surgery.
How is an ocular ultrasound done?
B ecography, which is the ocular ultrasound that we most frequently perform in our clinic, is very comfortable for the patient. It is done with closed eyes. A little gel is applied over the ultrasound probe, and we place the probe gently against the eyelids to perform the examination. The patient is often asked to look in different directions. The test lasts only a couple of minutes.