What can reduce the Specific Absorption Rate (SAR) during an MRI scan?

Reducing the Specific Absorption Rate (SAR) during an MRI scan is essential for patient safety, particularly in avoiding excessive heating of tissues due to energy absorption. One effective method to achieve this is by decreasing the flip angle.

The flip angle refers to the angle at which the magnetization of the tissue is rotated from its longitudinal position to the transverse plane during the radiofrequency (RF) pulse. A smaller flip angle results in lower energy being deposited into the tissues, thereby leading to a reduction in SAR. This is because a decreased flip angle corresponds to smaller RF pulse amplitudes, which directly reduces the power delivered during the imaging process.

This adjustment is particularly relevant in scenarios where patient safety is a concern, such as in patients who may be more susceptible to heat-induced effects or when prolonged scanning is necessary. By lowering the flip angle, technologists can optimize the imaging protocol to minimize potential risks while still obtaining high-quality imaging data.

In contrast, the other options do not effectively contribute to SAR reduction. Scanning larger patients tends to increase SAR due to more tissue absorbing the RF energy. Decreasing the repetition time (TR) would likely result in an increase in the number of RF pulses applied in a given timeframe, thereby increasing the energy delivered and