Electrode tracking for deep brain stimulation
An electromagnetic navigation system that tracks deep brain stimulation electrodes in real time during stereotactic neurosurgery.
- 1Electrode: several magnetic sensors along its length are located in real time as it moves towards the deep brain target.
- 2Stereotactic arc with two degrees of freedom (green arrows): it tilts around its pivots and the electrode holder slides along it. Three flexible PCBs with magnetic sensors clip onto it to track its position. Each sensing board, on the arc and on the electrode, runs an nRF52832.
- 3Magnetic field source with four coils, next to the head, and the nRF52840 master that drives the four sensing boards over BLE.
- 4Desktop application: sends commands to the system and logs every acquisition.
- Category
- Medtech & research
- Organization
- FHNW
- Period
- 2023 – 2026
- Technologies
- nRF52840, nRF52832, Zephyr, BLE, Flex PCB, Desktop app
- Website
- fhnw.ch ↗
Context
In deep brain stimulation, an electrode placed a few millimetres off target can cause side effects or make the treatment fail, yet surgeons cannot see it during implantation. Commercial electromagnetic trackers are disturbed by the metal stereotactic frame. ManaDBS, developed at the FHNW with the University of Strasbourg and the University Hospital Basel, places a magnetic field source next to the head and locates sensors on the electrode and on the stereotactic arc. In vitro, its accuracy (about 1.6 mm and 1°) was unaffected by the frame, whereas a commercial tracker degraded to 2.3 mm. Because the arc itself is tracked, the workflow needs no separate registration step.
My role
Developed the magnetic sensor acquisition system, on the same architecture as the 3D scanning textile: an nRF52840 master on the field source and four nRF52832 slaves (three flexible PCBs on the stereotactic arc, one on the electrode), all connected over BLE. Wrote the acquisition and synchronisation firmware, and the desktop application that sends commands and logs the acquisitions. Co-author of the related publications.