Fast "real time" imaging with different k-space update strategies for interventional procedures

Area of Science:

• Medical Imaging
• Interventional Radiology
• Magnetic Resonance Imaging (MRI)

Background:

• Interventional MRI requires fast imaging for real-time tool tracking and safe device placement.
• Low-field strength in open MRI systems often limits the balance between scan speed and image quality.
• Existing methods face trade-offs impacting temporal resolution and image fidelity during interventions.

Purpose of the Study:

• To design and describe novel keyhole strategies for real-time MRI acquisition.
• To enhance image frame rates in low-field interventional MRI systems.
• To improve the visualization of dynamic changes during interventional procedures.

Main Methods:

• Implementation of keyhole techniques and modified k-space trajectories.
• Integration with a fluoroscopic (continuous acquisition) mode and real-time reconstruction.
• Testing on open low-field (0.2T, 0.064T) and a 1.5T solenoidal MRI systems.

Main Results:

• Achieved image frame rate increases of up to 16 times.
• Enabled recognition of small object changes by updating the entire raw data space.
• Demonstrated feasibility across different MRI magnet designs and field strengths.

Conclusions:

• The developed keyhole strategies significantly enhance temporal resolution in interventional MRI.
• These methods offer a viable solution for improving real-time imaging in low-field systems.
• Potential applications extend to other areas needing high temporal resolution, such as contrast-enhanced breast and functional brain imaging.