Hemodynamic response magnetic resonance imaging: application for renal hemodynamic characterization

Area of Science:

• Medical Imaging
• Renal Physiology
• Functional MRI

Background:

• Contrast agents for renal perfusion imaging are limited in patients with kidney dysfunction.
• Hemodynamic response imaging (HRI) is a functional MRI technique previously shown to monitor liver hemodynamics.
• The study aimed to assess HRI's utility for evaluating renal perfusion and hemodynamics.

Purpose of the Study:

• To evaluate the utility of HRI for monitoring changes in renal perfusion and hemodynamics.
• To assess the feasibility of a non-invasive MRI technique for renal evaluation.

Main Methods:

• Renal HRI maps were acquired in mice under hypercapnia and hypercapnic-hyperoxia.
• HRI's utility was tested using pharmacological interventions and in a mouse model of acute kidney injury (AKI).
• Doppler ultrasound (US) was used to corroborate HRI findings.

Main Results:

• Renal HRI maps demonstrated significant signal changes indicating vascular reactivity.
• These signal changes were reduced with pharmacological inhibition and during AKI, indicating impaired perfusion.
• Doppler US confirmed the hampered perfusion dynamics observed with HRI.

Conclusions:

• Non-invasive HRI is applicable for assessing renal perfusion and vascular reactivity.
• HRI offers a contrast-agent-free alternative for evaluating kidney function.
• This method holds potential for diagnosing and monitoring kidney conditions, including AKI.