A Comparison of Micro-Ultrasound & Multiparametric MRI Imaging for Prostate Cancer: An International Meta-Analysis

Jennifer Schram Exact Imaging, Portfolio News

This work compares mpMRI with high-resolution 29MHz micro-ultrasound imaging, which maintains the workflow, simplicity and low cost of ultrasound and can be used to target biopsies without the need for MRI.

Comparison of Micro-Ultrasound and Multiparametric MRI Imaging for Prostate Cancer: An International Meta-Analysis
Giovanni Lughezzani (1), Ander Astobieta (2), Frédéric Staerman (3), Eric Klein (4), Robert Abouassaly (4), Ahmed El-Shefai (4), Gregg Eure (5)
(1) Instituto Clinico Humanitas, Rozzano, Italy, (2) Urología Clínica, Clínica IMQ Zorrotzaurre, Spain, (3) Polyclinique Reims-Bezannes, Reims, France, (4) Glickman Urological Institute, Cleveland Clinic, Cleveland, USA, (5) Urology of Virginia, Virginia Beach, USA

Introduction & Objectives

Multi-parametric MRI (mpMRI) is growing as a screening approach for prostate cancer due to high sensitivity and negative predictive value. Unfortunately, implementation is complicated due to additional costs, complexity, learning curve, procedure time, and experience required for adequate interpretation and reproducible results. Many men are also contraindicated due to renal function, claustrophobia, or ferromagnetic implants.

Materials & Methods

  • 280 subjects underwent prostate biopsy using the
    ExactVu™ micro-ultrasound system (Exact Imaging, Markham, Canada) at 5 urological centers in the USA and Europe
  • Samples in all subjects were taken from:
    • mpMRI targets (PI-RADS™ > 2, Cognitive fusion at 4 sites,
      software-assisted fusion at 1 site)
    • Micro-ultrasound targets (PRI-MUS™, > 2)
    • Up to 12 additional systematic samples filled in
  • Clinically significant cancer was considered any Gleason Sum > 6


Micro-ultrasound provided superior sensitivity to mpMRI for detection
of csPCa (p=0.002).

  • mpMRI demonstrated strong sensitivity (83%), with slightly weaker NPV
    (69%). Micro-ultrasound sensitivity (95%) and NPV (82%) were both
    higher. However, micro-ultrasound was less specific (17% vs 25% for
    mpMRI) and both modalities showed a relatively poor PPV of 43 and 44%.
Comparison of Micro-Ultrasound and Multiparametric MRI Imaging for Prostate Cancer: An International Meta-Analysis
Comparison of Micro-Ultrasound and Multiparametric MRI Imaging for Prostate Cancer: An International Meta-Analysis


  • Micro-ultrasound’s high sensitivity makes it an attractive option for
    guiding targeted biopsy relative to the more widely studied mpMRI
  • The slightly lower specificity suggests micro-ultrasound is not yet able to exclude biopsy in as many men, though this is expected to improve as more information on benign variants becomes available


  1. Ghai S, Eure G, Fradet V, et al: Assessing Cancer Risk on Novel 29 MHz Micro-Ultrasound Images of the Prostate: Creation of the Micro-Ultrasound Protocol for Prostate Risk Identification. J. Urol. 2016; 196: 562–569.
  2. Astobieta et al. Initial results comparing 29 MHz micro-ultrasound with multi-parametric MRI for targeted prostate biopsy: Relative sensitivity to clinically significant prostate cancer. Eur Urol Suppl. 2018;17(2):e901.
  3. Eure, et al. Comparison of Conventional TRUS, MRI and Micro-Ultrasound for Visualizing Prostate Cancer in an Active Surveillance Population. Can Urol Assoc J. 2018 Aug 30
  4. Lughezzani et al. Comparison between the diagnostic accuracy of high resolution micro-ultrasound versus multiparametric MRI in the detection of prostate cancer: Preliminary results from a single-institutional ongoing prospective trial. Eur Urol Suppl. 2018;17(8):179.
  5. Abouassaly, et al. Initial Results Comparing Micro-Ultrasound with MRI for Prostate Cancer Detection. ESUI 2018
  6. Staerman. Initial Clinical Experience with 29 MHz Micro-Ultrasound for Real-Time Targeted Prostate Biopsies. ESUI 2018

About Exact Imaging

Exact Imaging is the world’s leader in high-resolution micro-ultrasound systems enabling real-time imaging and guided biopsies in the urological market for prostate cancer. Exact Imaging’s ExactVu™ micro-ultrasound platform operates at 29 MHz and enables a whole new level of resolution with the benefits of ease of use, affordability, and is an extension of the current urological workflow. Using the Exact Imaging platform, urologists are able to visualize areas of interest in the prostate and specifically target biopsies at those areas. For the minority of cases where MRI might assist (i.e., prior negative biopsies), the FusionVu™ micro-US/MRI fusion application operates on the ExactVu micro-ultrasound platform and facilitates MRI fusion-based targeting. The ExactVu micro-ultrasound system including the FusionVu application have received regulatory approval in the European Union (CE Mark), the United States (FDA 510(k)) and Canada (Health Canada medical device license).

For further information, please contact:

Robert Sandler
SVP, Marketing
Exact Imaging
T. +1.416.274.8166
E. rsandler@exactimaging.com

Related Article: Results from ExactVu™ Micro-Ultrasound Studies Featured Prominently at the American Urological Association’s (AUA) 114th Annual Meeting in Chicago, IL