In a longitudinal scan of the eye, what is typically displayed at the bottom of the screen?

In a longitudinal scan of the eye, the display at the bottom of the screen typically shows the optic nerve. This is because longitudinal scans are oriented to image the eye in a plane that runs from anterior to posterior, allowing for the visualization of structures along that axis. The optic nerve, being located at the posterior aspect of the eye, becomes a prominent feature in this type of scan. The scan provides critical information about the health of the optic nerve and can help in assessing conditions such as glaucoma or optic nerve edema.

Other structures such as the lens, retina, and cornea may be displayed at different locations in the scan or in different types of imaging. For example, the lens is usually situated anteriorly, while the retina is posterior to the vitreous body and would appear higher up in the scan. The cornea, being the most anterior structure, typically appears at the top of the image. Thus, in a longitudinal scanning view, the optic nerve holds significance in both its position and relevance to various ocular conditions, making it the correct answer.