Which of the following ultrasound systems is primarily used for imaging tissue structures?

The B-scan ultrasound system is primarily utilized for imaging tissue structures due to its ability to create two-dimensional cross-sectional images of the eye and surrounding tissues. This technique offers a more detailed visualization compared to other modes because it generates real-time images that display the depth and shape of the structures being examined.

In a B-scan, multiple A-scans (which provide a single-dimensional representation of reflectivity at specific points) are combined to create a comprehensive view of anatomical structures. This is particularly useful for identifying abnormalities, assessing tumors, and visualizing layers of the eye, making it a crucial tool in ophthalmic diagnostics. The B-scan is integral in providing clinicians with essential information for evaluating the overall health and condition of the eye and its surrounding tissues.

Other ultrasound systems, such as A-scans, focus primarily on measuring distances and reflectivity rather than providing detailed images of structures, which is why they are not as suitable for the purpose outlined in the question.