What is the typical TI used in STIR to suppress fat signals?

In STIR (Short Tau Inversion Recovery) imaging, the typical TI (inversion time) used to suppress fat signals is indeed around 160 milliseconds. This value is chosen based on the T1 relaxation time of fat, which allows for effective signal nulling.

By applying the inversion pulse at this specific TI, fat signals are inverted and then nullified at the time of data acquisition, enhancing the visibility of surrounding tissues and lesions without the interference of fat signal. This technique is particularly useful in musculoskeletal imaging and abdominal studies, where fat can obscure pathology.

The other TI values are either too short or too long, not allowing for proper suppression of fat signals, which can lead to undesirable artifacts and reduce the clarity of the image. The approximately 160 mSec TI balances effective suppression with optimal imaging conditions, making it the standard choice in clinical practice.