B-Scan is a short term that refers to
the same procedure as "B-scan ultrasonography"
(but note that "ultrasonography" on its own is a much
more general term, not specific to examination of the eye).
A B-scan (or B-scan ultrasonography)
is a routine diagnostic test used in ophthalmology.
It involves examination of the tissues of the eye in cross-section, using
a high-frequency ultrasound technique. This technique is particularly
useful for examination of the back part of the eyeball, especially if
direct view is obscured due to the condition of the eye (e.g. by cataracts).
This may be compared and contrasted with the A-scan
(in which the axial length of the eye is examined in cross-section using
a high-frequency ultrasound machine).
This section includes short definitions of clinical and surgical procedures
concerning the eyes and human visual system. For definitions of other
terms in this category, choose from the list to the left.
Other related pages include the diagram
of the eye, and definitions
of parts of the eye, a description
of the human retina, and the section about disorders
of the eye and visual system.