Transperineal prostate MR elastography: initial in vivo results

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Physics

Background:

• Prostate cancer diagnosis relies on multiparametric MRI, but elasticity information is lacking.
• Current magnetic resonance elastography (MRE) methods for the prostate often require an endorectal coil, limiting patient comfort and applicability.

Purpose of the Study:

• To develop and validate a transperineal mechanical excitation approach for prostate magnetic resonance elastography (MRE).
• To assess the feasibility of this technique for detecting small prostate lesions and its potential integration into multiparametric MRI protocols.

Main Methods:

• Transperineal mechanical excitation using an electromagnetic actuator with hydraulic transmission.
• Reduced MRE acquisition time via a "second harmonic" approach.
• Processing displacement fields with 3D local frequency estimation and curl-based direct inversion for wavelength calculation.

Main Results:

• Successfully generated shear wave amplitudes of 6-30 μm in the prostate mid-gland.
• Resolved lesions as small as 0.5 cc in phantom studies.
• Demonstrated repeatability and potential for lesion detection without an endorectal coil.

Conclusions:

• Transperineal MRE is a viable, non-invasive technique for assessing prostate elasticity.
• This method can complement multiparametric MRI for improved prostate cancer diagnosis and surveillance.
• Further studies in patient populations are warranted to confirm clinical utility.