🧲 GRE-T2* Imaging

GRE-T2\* (Gradient-Recalled Echo T2-star) is a magnetic resonance imaging (MRI) sequence that is highly sensitive to magnetic field inhomogeneities, making it especially useful for detecting substances like blood products, iron, or calcium in the brain.

• Uses gradient echo rather than spin echo, making it faster but more susceptible to artifacts.
• Sensitive to susceptibility effects, such as those caused by hemosiderin, microbleeds, or calcifications.
• Called T2\* because it reflects both T2 decay and local magnetic field variations.
• Often used to detect:
  • Cerebral microbleeds
  • Cavernous malformations (CCM)
  • Calcifications
  • Old hemorrhages

• Typically acquired in 2D or 3D format.
• Produces “blooming effect” where small areas of blood or metal appear larger.
• Less sensitive than SWI (Susceptibility Weighted Imaging) for small venous structures or subtle findings.

• Use GRE-T2* when time or access to advanced MRI sequences is limited.
• Prefer SWI or CE-T1 for detailed evaluation of developmental venous anomalies (DVAs) or subtle microvasculature.