Partial volume effects in dynamic contrast magnetic resonance renal studies

Area of Science:

• Medical Imaging
• Renal Physiology
• Magnetic Resonance Imaging

Background:

• Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is used to assess kidney function.
• The partial volume effect, where voxels contain multiple tissue types, can introduce errors in DCE-MRI analysis.
• Accurate quantification of renal function is crucial for diagnosing and managing kidney diseases.

Purpose of the Study:

• To investigate and quantify the partial volume effect in renal DCE-MRI.
• To assess the impact of partial volume correction on glomerular filtration rate (GFR) estimation.
• To evaluate the improvement in data fitting using the Rutland-Patlak model after partial volume correction.

Main Methods:

• Acquired dynamic image data from 10 healthy volunteers using DCE-MRI.
• Applied respiratory motion correction and developed a method to assign mixing vectors to each voxel.
• Recovered true tissue intensities by deconvolving voxel data, eliminating non-renal tissue contributions.
• Utilized the Rutland-Patlak model for time-intensity curve analysis before and after partial volume correction.

Main Results:

• Partial volume correction successfully eliminated non-renal tissue contributions from renal time-intensity curves.
• A significant change in the early slope of the renal curve was observed post-correction.
• The corrected analysis showed a 36% mean enhancement in relative GFR and a 7% improvement in the r(2) fitting of the Rutland-Patlak model.

Conclusions:

• The partial volume effect substantially influences renal function quantification in DCE-MRI.
• Partial volume correction is essential for accurate GFR estimation using DCE-MRI.
• This study highlights the importance of addressing partial volume effects for reliable renal imaging analysis.