XYZ-IRM - 3D Hall effect sensor on a chip for 3D localization inside the MRI
The alignment of the MR scan planes to the interventional instrument (e.g. biopsy/ablation needle, catheter) in order to monitor the procedure is a demanding and timeconsuming task. Gradient-based tracking techniques, that do not require NMR signal, have already been proposed based on small orthogonal inductive coils to measure dedicated gradients along the X, Y and Z MRI-axis. Position and orientation of the sensor are then computed based on gradient maps. The use of 3 orthogonal 1D Hall sensors was proposed as an alternative to inductive coil. However, such architecture suffers from misalignment of the 3 sensors.
The SMH team of ICube (L. Hébrard) developped a prototype 3D Hall effect sensor on a chip designed in standard CMOS technology. The circuit integrates 2 horizontal Hall effect sensors, and a new vertical Hall effect sensor capable of measuring magnetic fields perpendicular to the chip plane. This circuit has a very small form factor and could be directly printed into medical instruments. The 3D pose (position and orientation) of the chip is determined by successively measuring 3 orthogonal magnetic field gradients.
The AVR team developps the interactive MRI pulse sequence, the localization algorithm and the user-interface software for real-time tracking inside the MRI.
Contacts in AVR
L. Cuvillon E. Breton
The project started with Ermergence ANR funding. Since September 2014, the project is funded on a valorization grant from SATT Conectus.
- Our start-up project won the BPI France i-LAB 2015 Emergence funding.
- First Prize for technical development of the Interventional MRI Study Group at ISMRM 2014, Milan: Real-time automatic tracking with a dedicated 3D Hall-effect integrated circuit for MRI-guided interventions L. Cuvillon, E. Breton, J-B Schell, J-B Kammerer, D. Gounot, L. Hébrard and M. de Mathelin.