Ultrahigh-resolution quantitative spinal cord MRI at 9.4T

Area of Science:

• Neuroimaging
• Magnetic Resonance Imaging (MRI)
• Spinal Cord Anatomy

Background:

• Advancements in high-field MRI offer potential for improved visualization of the human spinal cord.
• Previous studies have explored spinal cord imaging at lower field strengths, with limitations in resolution and detail.

Purpose of the Study:

• To present the initial findings from in vivo human spinal cord MRI scans acquired at an ultra-high field strength of 9.4 Tesla (9.4T).
• To evaluate the feasibility and performance of a human brain coil for spinal cord imaging at 9.4T.

Main Methods:

• Utilized a 9.4T MRI scanner with a specialized human brain coil for spinal cord imaging.
• Acquired T2*-weighted gradient-echo anatomical images and compared the efficacy of different B0 shimming techniques.
• Determined intrinsic signal-to-noise-ratio (SNR) and calculated T2*-relaxation times using multi-echo acquisitions.
• Assessed algorithmic approaches for spinal cord detection and gray/white matter segmentation.

Main Results:

• Achieved a maximum in-plane resolution of 0.15 x 0.15 mm², surpassing previously reported 7T results.
• Demonstrated excellent image quality, clearly visualizing small spinal cord structures.
• Reported intrinsic SNR values ranging from 6600 to 8060 in the upper cervical spinal cord.
• Calculated average T2* relaxation times: 24.88 ms ± 6.68 ms for gray matter and 19.37 ms ± 8.66 ms for white matter.

Conclusions:

• Confirmed the successful application of a human brain coil for high-resolution in vivo spinal cord imaging at 9.4T.
• The achieved resolution and image quality at 9.4T significantly enhance the visibility of spinal cord microstructures.
• The findings support the potential of 9.4T MRI for detailed spinal cord investigations.