What happens to temporal resolution if the number of scan lines increases?

Temporal resolution refers to the ability to distinguish events that occur at different times; in diagnostic ultrasound, it reflects how quickly frames can be acquired and displayed. When the number of scan lines in an ultrasound image is increased, the overall time required for the system to acquire and process the entire image also increases. This is because each additional scan line adds to the total time needed to complete a frame, which in turn can lead to a lower frame rate.

A lower frame rate will result in a sacrifice of temporal resolution, as fewer images are captured over a given period of time. Consequently, dynamic processes, such as blood flow or the movement of structures, may not be as clearly visualized, making it more challenging to assess moving targets accurately.

In summary, increasing the number of scan lines leads to a decrease in temporal resolution because it takes longer to acquire each frame, compromising the system's ability to provide detailed real-time imaging.