Dissolved hyperpolarized xenon-129 MRI in human kidneys

Area of Science:

• Magnetic Resonance Imaging
• Medical Physics
• Renal Physiology

Background:

• Assessing renal physiology noninvasively is crucial for diagnosing kidney diseases.
• Current methods may have limitations in spatial resolution or invasiveness.
• Hyperpolarized contrast agents offer enhanced signal for MRI.

Purpose of the Study:

• To evaluate the feasibility of using dissolved hyperpolarized xenon-129 (¹²⁹Xe) MRI at 3 Tesla for studying human renal physiology.
• To explore the potential of ¹²⁹Xe MRI as a noninvasive tool for kidney imaging.

Main Methods:

• Dynamic, spatially resolved ¹²⁹Xe spectroscopy was performed in 3 healthy males after inhaling hyperpolarized ¹²⁹Xe gas.
• A custom transmit-only, receive-only RF coil array was developed to enhance kidney signal sensitivity.
• Spoiled gradient echo and balanced steady-state sequences were used for imaging ¹²⁹Xe uptake.

Main Results:

• Spatially resolved spectroscopy differentiated ¹²⁹Xe signals in red blood cells and tissue/plasma within the kidneys and aorta.
• The custom coil array provided over a 3-fold increase in signal-to-noise ratio (SNR) in the kidneys compared to surrounding tissues.
• Physiological information on ¹²⁹Xe transit to the kidneys was obtained using a transceiver coil.

Conclusions:

• Hyperpolarized ¹²⁹Xe MRI successfully measured dissolved ¹²⁹Xe uptake in human kidneys.
• This technique demonstrates significant potential as a novel, noninvasive method for imaging human kidney tissue perfusion.
• ¹²⁹Xe MRI offers a promising new avenue for noninvasive renal physiological assessment.