Streamlined calculation of kidney function using dynamic contrast-enhanced MRI with population-based arterial input...

Area of Science:

• Nephrology
• Radiology
• Medical Imaging

Background:

• Dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) is valuable for assessing kidney function.
• Traditional DCE-MRI methods suffer from artifacts and complex post-processing, limiting clinical utility.
• Accurate estimation of glomerular filtration rate (eGFR) and renal plasma flow (RPF) is crucial for kidney health assessment.

Purpose of the Study:

• To develop and validate a simplified DCE-MRI post-processing method for estimating kidney function.
• To combine a population-based arterial input function (pAIF) with a whole-kidney pharmacokinetic model (WKPM).
• To compare DCE-MRI derived eGFR and RPF with established clinical measures (serum eGFR and ASL-derived RPF).

Main Methods:

• Prospective single-center study involving 43 patients undergoing multiparametric 1.5-T MRI.
• DCE-MRI with high temporal resolution and background-suppressed pseudocontinuous arterial spin labeling (ASL) were acquired.
• Whole-kidney pharmacokinetic modeling (WKPM) was used with both individual-based (iAIF) and population-based (pAIF) arterial input functions.
• Statistical analyses included Pearson correlation and Bland-Altman analysis to compare methods.

Main Results:

• DCE-MRI eGFR derived using pAIF showed stronger correlation (r=0.61) with serum eGFR than iAIF (r=0.33).
• DCE-MRI RPF derived using pAIF demonstrated a stronger correlation (r=0.65) with ASL-derived RPF compared to iAIF (r=0.53).
• The pAIF method exhibited lower Bland-Altman bias for both eGFR and RPF compared to the iAIF method.

Conclusions:

• DCE-MRI combined with pAIF and WKPM offers a simplified and robust approach for estimating single-kidney function.
• This streamlined method minimizes artifacts and complex segmentation, enhancing clinical feasibility.
• The findings support broader adoption of renal DCE-MRI in routine clinical practice for improved kidney function assessment.