C11466: One-Step MRI Method to Increase Image ContrastNovelty:
A new method of measuring transverse relaxation time (T2), T2 imaging and T2 contrast in MRI.
Value Proposition:
T2-contrast is essential to diagnostic MRI in a multitude of disorders. Prior methods utilize the spin-echo (SE) method to measure T2 and to generate T2contrast. The SE method involves multiple MRI pulse applications that contribute to RF power deposition, and confound other MRI properties of interest. The current invention provides a new method that avoids SE, that can preserve other MRI sequence properties, and which is easily implemented on existing clinical MRI scanners. The method provides T2-weighted MRI contrast in a single step, and/or T2 measurements in two acquisitions. Other advantages include:
• First method to use a single excitation pulse to encode T2.
• First method that uses adiabatic pulses to measure T2.
• In MRI embodiments, the method is first to use excitation pulses with zero effective flip-angles that produceT2-encoding only.
• Because T2-encoding precedes the regular MRI pulse sequence and uses zero effective flip-angle, the sequence’s other contrast and/or encoding properties are preserved.
• The method is less sensitive to variations in the excitation magnetic field.
• The method is easily implemented in existing clinical MRI scanners.
Technical Details:
Differences in T2 provide an important contrast mechanism in MRI. T2 is conventionally measured by the SE method which uses a 90°-180° pulse pair separated by delays of TE/2, with signal acquired at time TE. In MRI, this is combined with spatial localization to obtain T2 images and/or images with T2-enhanced contrast or 'T2-weighting". Johns Hopkins researchers have developed a new method of measuring T2 without SEs, utilizing the fact that long-duration adiabatic excitation pulses are prone to T2 decay during excitation. The method is demonstrated with low-angle adiabatic pulses whose flip-angles can be arbitrarily set. By preceding a regular MRI pulse sequence with a single long 0° adiabatic pulse, T2 contrast or “T2-preparation” is provided without affecting the rest of the sequence. Repeating the sequence without the adiabatic pulses enables generation of T2-images.
Looking for Partners:
To develop and commercialize the technology as a method that improves T2 measurements using existing NMR/clinical MRI operational software.
Stage of Development:
Pre-Clinical
Data Availability:
The method is validated on phantoms by comparison with the SE method, and reduced to practice in in human MRI studies at 3 Tesla.
Publications/Associated Cases:
Journal of Magnetic Resonance Vol. 214 pg. 273-280
