Impact of Nonrigid Motion Correction Technique on Pixel-wise Pharmacokinetic Analysis of Free-breathing Pulmonary Dynamic Contrast-enhanced MR Imaging.

Citation:

Junichi Tokuda, Hatsuho Mamata, Ritu R Gill, Nobuhiko Hata, Ron Kikinis, Robert F Padera, Robert E Lenkinski, David J Sugarbaker, and Hiroto Hatabu. 2011. “Impact of Nonrigid Motion Correction Technique on Pixel-wise Pharmacokinetic Analysis of Free-breathing Pulmonary Dynamic Contrast-enhanced MR Imaging.” J Magn Reson Imaging, 33, 4, Pp. 968-73. Copy at http://www.tinyurl.com/l87qh8o

Abstract:

PURPOSE: To investigates the impact of nonrigid motion correction on pixel-wise pharmacokinetic analysis of free-breathing DCE-MRI in patients with solitary pulmonary nodules (SPNs). Misalignment of focal lesions due to respiratory motion in free-breathing dynamic contrast-enhanced MRI (DCE-MRI) precludes obtaining reliable time-intensity curves, which are crucial for pharmacokinetic analysis for tissue characterization. MATERIALS AND METHODS: Single-slice 2D DCE-MRI was obtained in 15 patients. Misalignments of SPNs were corrected using nonrigid B-spline image registration. Pixel-wise pharmacokinetic parameters K(trans) , v(e) , and k(ep) were estimated from both original and motion-corrected DCE-MRI by fitting the two-compartment pharmacokinetic model to the time-intensity curve obtained in each pixel. The "goodness-of-fit" was tested with χ(2) -test in pixel-by-pixel basis to evaluate the reliability of the parameters. The percentages of reliable pixels within the SPNs were compared between the original and motion-corrected DCE-MRI. In addition, the parameters obtained from benign and malignant SPNs were compared. RESULTS: The percentage of reliable pixels in the motion-corrected DCE-MRI was significantly larger than the original DCE-MRI (P = 4 × 10(-7) ). Both K(trans) and k(ep) derived from the motion-corrected DCE-MRI showed significant differences between benign and malignant SPNs (P = 0.024, 0.015). CONCLUSION: The study demonstrated the impact of nonrigid motion correction technique on pixel-wise pharmacokinetic analysis of free-breathing DCE-MRI in SPNs.

Last updated on 10/07/2016