gradient recalled echo
Also written as: GRE — Gradient Recalled Echo
MRI sequence particularly sensitive to magnetic susceptibility effects, useful for detecting blood products and calcifications.
Full Definition
Gradient recalled echo (GRE) is a rapid MRI pulse sequence that uses gradient fields rather than radiofrequency pulses for signal readout. This technique is highly sensitive to magnetic susceptibility effects, making it excellent for detecting blood products, calcifications, and iron deposition. T2*-weighted GRE sequences are particularly valuable in trauma imaging for identifying microhemorrhages and in stroke evaluation for detecting hemorrhagic transformation. The speed of acquisition makes GRE sequences useful for motion-sensitive applications and when rapid imaging is required in unstable patients.
Usage
Usage note: Specify T1 or T2* weighting when clinically relevant for interpretation.
In Context
- "GRE sequences revealed multiple punctate hypointensities consistent with microhemorrhages." — Traumatic brain injury imaging
- "T2* gradient recalled echo imaging showed no evidence of hemorrhagic transformation." — Post-thrombolysis follow-up