Magnetic Resonance Imaging (MRI) Practice Test

What are Short Tau Inversion Recovery sequences typically NOT used for?

1. Assessing white matter lesions

2. Evaluating melanoma

3. Evaluating fluid (CSF)

4. Detecting bone marrow edema

The correct answer is: Evaluating fluid (CSF)

Short Tau Inversion Recovery (STIR) sequences are particularly useful in MRI imaging due to their ability to suppress signal from fat, making them valuable for various applications. They are commonly employed in the assessment of conditions affecting soft tissues, including white matter lesions and bone marrow edema. When it comes to evaluating fluid, such as cerebrospinal fluid (CSF), STIR sequences are not typically used. This is because the suppression of fat signals may not provide the required contrast against fluid, which is often best visualized using other sequences, such as T2-weighted imaging. T2-weighted images show CSF with high signal intensity, allowing for clear assessment of conditions like hydrocephalus or other pathologies involving fluid accumulation. In contrast, STIR sequences excel at highlighting disruptions in soft tissue or pathology associated with edema or lesions, making them less suitable for fluid evaluation specifically. Therefore, the choice of sequences is crucial for obtaining accurate diagnostic information based on the nature of the tissue being evaluated.