Ultrasonography

Ultrasonography is an ultrasound-based imaging tool used to diagnose a variety of conditions in various internal body structures. While ultrasonography is most commonly known for its use in obstetrics, there are a variety of medical fields that utilize this technology for diagnostic and therapeutic applications.

There are two types of ultrasonography used in the field of ophthalmology: A-scan ultrasonography and B-scan ultrasonography.

A-Scan Ultrasonography

A-scan ultrasonography, more commonly called an A-scan, enables ophthalmologists to examine the length of the eye, which impacts many common sight disorders. A-scans are most commonly used to evaluate eye length in conjunction with determining intraocular lens power during cataract surgery. When removing a cataract, your eye doctor will calculate the appropriate power of your intraocular lens by applying a formula to the measurements taken of your eye length by the A-scan and your cornea’s power using keratometry.

A-scans are also sometimes used to evaluate masses in the eye. This is generally called a quantitative A-scan.

B-Scan Ultrasonography

B-scan ultrasonography, commonly called a B-scan, is used to assess a variety of eye diseases. This assessment enables your ophthalmologist to gather a great deal of information that cannot be detected from a standard eye evaluation.

B-scans are commonly employed when it is difficult to directly examine intraocular structures. The following conditions often require the use of a B-scan:

Lid problems
Keratoprosthesis
Corneal opacities
Hyphema
Hypopyon
Miosis
Pupillary membranes
Dense cataracts
Vitreous opacities

When these conditions are present, a B-scan can provide your ophthalmologist with a wealth of information on the status of the eye’s lens, vitreous, retina, choroid, and sclera.

To learn more about ultrasonography and other diagnostic ocular imaging technology, please contact an eye doctor in your area.