MRI-guided biopsy to correlate tissue specimens with MR elastography stiffness readings in liver transplants.

Rationale And Objectives: Magnetic resonance elastography (MRE) can noninvasively measure the stiffness of liver tissue and display this information in anatomic maps. Magnetic resonance imaging (MRI) guidance has not previously been used to biopsy segments of heterogeneous stiffness identified on MRE. Dedicated study of MRE in post-liver transplant patients is also limited. In this study, the ability of real-time MRI to guide biopsies of segments of the liver with different MRE stiffness values in the same post-transplant patient was assessed.

Materials And Methods: MRE was performed in 9 consecutive posttransplant patients with history of hepatitis C. Segments of highest and lower stiffness on MRE served as targets for subsequent real-time MRI-guided biopsy using T2-weighted imaging. The ability of MRI-guided biopsy to successfully obtain tissue specimens was assessed. The Wilcoxon signed-rank test was used to compare mean stiffness differences for highest and lower MRE stiffness segments, with α = 0.05.

Results: MRI guidance allowed successful sampling of liver tissue for all (18/18) biopsies. There was a statistically significant difference in mean MRE stiffness values between highest (4.61 ± 1.99 kPa) and lower stiffness (3.03 ± 1.75 kPa) (P = .0039) segments biopsied in the 9 posttransplant patients.

Conclusion: Real-time MRI can guide biopsy in patients after liver transplantation based on MRE stiffness values. This study supports the use of MRI guidance to sample tissue based on functional information.