Assessment of the kidney function parameters split function, mean transit time, and outflow efficiency using dynamic...

Area of Science:

• Nuclear medicine
• Medical imaging
• Renal physiology

Background:

• Isotope nephrography is the standard for assessing kidney function.
• A novel method using dynamic FDG PET/MRI is proposed for kidney function assessment.
• This study aims to evaluate split function (SF), mean transit time (MTT), and outflow efficiency (OE) using FDG PET.

Purpose of the Study:

• To determine split function (SF), mean transit time (MTT), and outflow efficiency (OE) using 2-deoxy-2-[18F]fluoro-D-glucose (FDG) dynamic positron emission tomography (PET).
• To compare FDG PET-derived kidney function parameters with those obtained from traditional Technetium-99m-mercaptoacetyltriglycine (MAG3) scintigraphy.

Main Methods:

• Healthy subjects underwent simultaneous dynamic FDG-PET/MRI and MAG3 scintigraphy.
• Time-activity curves (TACs) were derived from PET and scintigraphy data for kidneys, cortices, and aorta.
• SF was calculated from TAC integrals, MTT from deconvolution analysis, and OE from MTT.

Main Results:

• Dynamic FDG PET/MRI showed strong correlations with MAG3 scintigraphy for total kidney SF (r=0.75), MTT (r=0.74), and OE (r=0.81).
• Significant differences were observed in the means of MTT and OE between the two methods (p < 0.0001).
• No significant correlations were found for renal cortex FDG values.

Conclusions:

• Dynamic FDG PET/MRI can accurately estimate SF, MTT, and OE in healthy kidneys.
• This method provides an advantage for patients undergoing routine PET/MRI scans.
• Kidney function parameters can be assessed simultaneously with functional and morphological imaging with high accuracy.