Control of a wireless sensor using the pulse sequence for prospective motion correction in brain MRI

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Biomedical Engineering
• Medical Physics

Background:

• Prospective motion correction is crucial for maintaining image quality in MRI.
• Existing methods for synchronizing external devices with MRI pulse sequences can be complex and invasive.
• Wireless motion-tracking devices offer a promising avenue for real-time motion compensation.

Purpose of the Study:

• To develop and validate a system for synchronizing a wireless motion-tracking device with MRI pulse sequences.
• To implement customizable navigator interleaving schemes for enhanced motion correction.
• To demonstrate the versatility of the system across different MRI pulse sequences.

Main Methods:

• A wireless motion-tracking device was modified with RF detection capabilities to identify unique RF signatures.
• RF signatures were paired with MRI navigators to trigger device readouts synchronously with the pulse sequence.
• The system was tested on 3D RF-spoiled gradient echo and PROPELLER (periodically rotated overlapping parallel lines with enhanced reconstruction) sequences at 3T and 1.5T.

Main Results:

• The system successfully rejected parent pulse sequence excitations and decoded RF signatures.
• Distortions in 3D gradient echo sequences were corrected by interleaving flipped polarity navigators.
• Scan duration was reduced by 54% by segmenting navigators, and motion correction was successfully performed on PROPELLER sequences.
• No hardware or software modifications were needed for the wireless device across different field strengths.

Conclusions:

• The proposed RF signature-based triggering scheme facilitates seamless interaction between wireless devices and MRI pulse sequences.
• This enables repeatable, versatile, and minimally invasive prospective motion correction.
• The system holds significant potential for improving MRI robustness and patient comfort.