M7 SimPETᵀᴹ

Simultaneous PET/MR Acquisition

System Overview

The M7 SimPET is a true simultaneous PET/MRI system utilizing the compact, permanent magnet technology in the M7 and the state-of-the-art SimPET insert. This system combines all of the benefits of the M-Series high-performance MRI systems with the state-of-the-art SimPET insert from Brightonix Imaging. The M7 System from Aspect Imaging is a self-shielded, cryogen free, MRI system that provides optimized imaging protocols for a variety of anatomical targets, providing complementary 3D anatomical images to those acquired using the SimPET insert. The SimPET “S” and “L” model insert, from Brightonix, have been optimized for use within the M7 system. Brightonix created an advanced silicon photomultiplier (SiPM) based PET insert for truly simultaneous PET/MR imaging.

The M7 system is ideally suited for MR imaging of mice, rat, and similarly sized animals, however when the SimPET insert is installed the imaging volume is limited to that of mice an similarly sized animals. The SimPET is loaded from one side of the magnet, while the M7 animal handling system with RF coil is loaded from the other. Aspect Imaging has created an RF coil optimized for use with the SimPET insert to ensure true compatibility of the two imaging modalities.

In the video above the M7 animal handling system enters the bore from the right, with the RF coil in place, while the SimPET insert enters from the left to incircle the RF coil.

The SimPET-S and L model insert, from Brightonix, have been optimized for use within the M7 system. Brightonix has created an advanced silicon photomultiplier (SiPM) based PET insert for truly simultaneous PET/MR imaging. The engineering team at Brightonix has developed a state-of-the-art, compact, insert with low power consumption and excellent PET detector stability.

There are four (4) different models of SimPET inserts available, they vary in inner/outer diameter and axial field of view. As mentioned above the SimPET-S and SimPET-L models have been optimized for use with the M7 MRI system from Aspect Imaging; the other models are optimized for use with some of the most commonly used high-field (>3T) superconducting MRI systems from preclinical imaging. Please refer to the Brightonix Imaging Technical Specifications for complete details.


The PET workstation software is intuitive and easy to use, as is the workstation for the M7 system. The images are acquired simultaneously by both systems, and co-registered within InviCROs VivoQuant visualization software provided with the systems.

On the PET workstation the user is provided with real-time count rate monitoring, FastTomo reconstruction, along with in-line image reconstruction, all with flexible list-mode data acquisition. Calibration procedures for quality control, PET/MR geometry, as well as count rate/activity are all included within the software. Quantification is provided in Bq/ml or standardized uptake value (SUV).

The highly sensitive LSO (lutetium oxyorthosilicate) detectors provide a best-in-class sub-millimeter spatial resolution while maintaining count-rate performance to allow for both low and high-dose imaging applications.

Simultaneous acquisition of both the PET and MR images on the M7 SimPETTM allows for both spatial and temporal understanding of the PET signal with regards to the anatomical image. MRI is the gold standard in soft tissue imaging, providing not only anatomical reference for the PET signal, but may also in itself provide some additional information with regards to the tissues being imaged. Various image weighting protocol exist to help identify abnormal or pathological tissues, along with the added benefit of using specific and perhaps multi-modal contrast agents to further elucidate the molecular pathway or imaging target of interest.

Features & Benefits

There are several key benefits of the M7 SimPETTM system:

SimPET Insert from Brightonix Imaging
  • Exceptional PET performance, optimized for standalone or simultaneous with MR imaging

  • Highly sensitive detectors provide sub-millimeter spatial resolution

  • State-of-the-art silicon photomultiplier technology allows for compact design with low power consumption

  • Acquisition and reconstruction software are intuitive and simple to use
M7 High-Performance MRI system from Aspect Imaging
  • Compact, permanent magnet, which is self-shielded making it easy to install right next to other imaging or laboratory equipment

  • No cryogens, or liquid of any kind for cooling, simple fans are used as needed to pull room air over the gradients, making ongoing running and maintenance costs minimal

  • Optimized image acquisition for numerous imaging targets, allowing biologists without a background in MR imaging to acquire high quality images on their imaging target

  • Simultaneous PET/MR imaging or standalone use
M7 SimPETTM System:
  • Fully integrated system with no compromise to MR or PET image quality or homogeneity

  • MRI-based attenuation correction of PET images

  • Complete system installed in one day


Performance Evaluation

A recent publication in Molecular Imaging and Biology provides the full details of the system performance, a summary of some key outcomes is provided here.

This authors followed the NEMA NU 4-2008 standard to assess the performance of the SimPET-S insert, along with it’s performance within the M7, compact, permanent magnet MRI system from Aspect Imaging.

Past Webinars - SimPET

Publications & Articles