The Prototype

Overall architecture

Gamma MRI is a combination of an MRI system with additional gamma detection. As a result, the overall architecture is composed of these two main subsystems: low magnetic field MRI and gamma detectors. Two consoles linked by a synchronization mechanism ensure tight integration of both system components.

The Data Acquisition Electronics

Hardware components:

The MRI device is organised, in terms of pulse generation hardware, around two main boards: FPGA core board to numerically generate the different pulses at hight speed rate and input/output MRI board to convert the generated waveform in analogical signal.

Software components:

The main user interface of the system is made in Java and runs under Windows to facilitate ease of use and portability. The pulse sequence kernel is designed as a smart graphical editor with an additional Java code layer that allows advanced calculations. It is compatible with common IDEs and integrates git versioning of the sequence.

The Gamma Source

As part of the GAMMA source, HESSO developed a complete software suite to facilitate the supervision and control of the different components of the system; including:

  • Automatic laser control,
  • Real time control of the temperature of the Laser
  • Control of the Cooling system of the oven for temperature stability.
  • Safety interlocks.

The Detectors

The gamma detectors fit inside openings made inside the magnet structure. To determine the optimal detector features, different simulations are carried out, with different variable parameters, so as to reach a final optimal design that meets the original requirements in the most effective way.

The Magnet

The magnet was custom-built based on the exact specifications provided by the consortium. However the shims and gradients were built internally by us because we could not find a supplier able to do the work.