Which of the following choices represents a disadvantage of increased RF pulse bandwidth?

Increased RF pulse bandwidth is associated with a variety of effects on MRI imaging, and one of the key disadvantages is that it can lead to reduced slice resolution. When the bandwidth of the RF pulse is increased, the range of frequencies that are excited also widens. This broader frequency range can affect how finely the system is able to resolve different slices of tissue.

Reduced slice resolution occurs because the wider bandwidth results in a thicker slice profile. As slices become thicker, the ability to distinguish between closely situated structures diminishes, leading to potential overlap and loss of detail. This can compromise the clarity of the images and reduce the overall diagnostic utility of the scan, especially in areas where high resolution is critical.

The other options describe outcomes that do not directly correlate with disadvantages associated with increased RF bandwidth. For instance, increased signal-to-noise ratio and better fat suppression are positive outcomes associated with a broader bandwidth. Increased acquisition time does not necessarily result from increased bandwidth; it primarily influences the speed at which data can be collected, depending on other factors like the number of signals averaged and TR (repetition time). Thus, reduced slice resolution stands out as a disadvantage of increased RF pulse bandwidth in MRI.