Transperineal prostate MR elastography: Initial in vivo results

Abstract

This article presents a new approach to magnetic resonance elastography of the prostate using transperineal mechanical excitation. This approach is validated using a prostate elasticity phantom and in vivo studies of healthy volunteers. It is demonstrated that the transperineal approach can generate shear wave amplitudes on the order of 6–30 μm in the mid‐gland region. The driver was implemented using an electromagnetic actuator with a hydraulic transmission system. The magnetic resonance elastography acquisition time has been reduced significantly by using a “second harmonic” approach. Displacement fields are processed using the established three‐dimensional local frequency estimation algorithm. The three‐dimensional curl‐based direct inversion was used to calculate the local wavelength. The traveling wave expansion algorithm was used to reconstruct the wave damping image for one case. Using the proposed method, it was possible to resolve lesions of 0.5 cc in the phantom study. Repeatability experiments were performed and analyzed. The results from this study indicate that transperineal magnetic resonance elastography—without an endorectal coil—is a suitable candidate for a patient study involving multiparametric magnetic resonance imaging of prostate cancer, where magnetic resonance elastography may provide additional information for improved diagnosis and image‐based surveillance. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.

Tumour biomechanical response to the vascular disrupting agent ZD6126 in vivo assessed by magnetic resonance elastography

“…Increased tissue stiffness is often associated with an invasive and malignant tumour phenotype (Paszek et al , 2005; Dvorak et al , 2011). Elastography, and MRE in particular, is an emerging imaging technique being used to measure tissue mechanical properties in vivo , and has shown promise in cancer diagnosis (Siegmann et al , 2010; Garteiser et al , 2012; Sahebjavaher et al , 2013). The overall aim of this study was to evaluate viscosity and elasticity as imaging biomarkers of response to the vascular disrupting agent ZD6126 in SW620 colorectal murine xenografts.…”

Magnetic resonance elastography of abdomen

“…Evaluation of prostate via transrectal and transperineal approaches has been described [110, 111]. Other organs to be explored include bowel and urinary bladder.…”

Patient-Activated Three-Dimensional Multifrequency Magnetic Resonance Elastography for High-Resolution Mechanical Imaging of the Liver and Spleen

“…Our feasibility study in a group of ten healthy volunteers paves the road for further in-depth evaluation of mechanical imaging in the abdomen. Potential applications of high clinical relevance include the kidney [40], prostate [41,42], and cervix [43,44]. A further perspective of abdominal 3D-MMRE is the noninvasive assessment of tissue pressure by evaluating volumetric strain [19] or poroelastic parameters [45].…”