Why is ultrasonography used in ophthalmology?

Ultrasonography is used in ophthalmology primarily to create images of the eye's internal structures. This imaging technique provides detailed information about various components within the eye that might not be visible using standard examination methods. For instance, ultrasonography can be particularly useful in assessing the lens, vitreous body, retina, and even the optic nerve. It allows clinicians to visualize conditions like retinal detachments, tumors, and congenital abnormalities, which aids in diagnosis and treatment planning.

The other options do not accurately represent the primary function of ultrasonography. Assessing visual acuity involves a different set of tests that evaluate the clarity and sharpness of vision, typically using charts and optotype letters. Measuring intraocular pressure is usually done through tonometry, which relies on different technologies such as applanation or non-contact tonometry, rather than ultrasonic imaging. Testing color vision involves specific assessments to determine the ability to perceive different colors, which is unrelated to the structural imaging capabilities of ultrasonography. Thus, the choice regarding the creation of images of the internal structures of the eye captures the essential role that ultrasonography plays in ophthalmic practice.