Neural Noise

Clinical translation of ultrasoft Fleuron probes for bidirectional brain interfaces

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  • Ultrasoft Fleuron™ probes are in clinical translation for stable, high-density, bidirectional brain interfaces.1
  • The work addresses recording stability and read/write capability in neural interfaces.1 1

Gardner updates

  • Clinical translation of ultrasoft Fleuron probes targets stable, high-density recording and bidirectional (read/write) brain interfaces (medRxiv preprint). 1

Weekly enrichment (2026-07-20)

  • The underlying primary preprint (medRxiv, April 2025; PubMed 40313281) introduces Fleuron, a family of ultrasoft, ultra-low-k dielectric materials compatible with scalable thin-film microfabrication, engineered to overcome the density-versus-chronic-stability trade-off of rigid iBCI materials like polyimide or silicon.2
  • Up to 1,024 recording sites were integrated into a single minimally invasive Fleuron depth electrode, coupled to a low-power mixed-signal ASIC to realize over 1,000-channel electronic interfaces.2
  • In rodent models, Fleuron enabled single-unit-resolution recordings for 18 months; 128-channel probes covered 8× larger tissue volume than state-of-the-art polyimide counterparts and tracked over 100 single units across months.2
  • Recording stability correlated with reduced glial encapsulation versus polyimide controls up to 9 months post-implantation.2
  • Probes were implanted at depth via a minimally invasive burr-hole approach without specialized robotics, produced a distinctive contrast on clinical 3T MRI for post-operative position confirmation, and passed large-animal and ex vivo human-tissue safety/function studies.2
  • In a first-ever intraoperative human use during planned resection surgeries, Fleuron probes recorded stable, high-resolution single-unit activity at depth, including evoked responses to auditory oddball paradigms measuring neural correlates of consciousness.2
  • Company context: Axoft (Cambridge, MA; co-founder Paul Le Floch) reports Fleuron is ~10,000× softer than polyimide, reducing tissue scarring and lead migration; its first-in-human FINESSE study completed its first four cases with The Panama Clinic and plans a second study with a more advanced iBCI.3
  • Parallel context: related soft, high-density platforms are advancing — e.g., Spiral-NeuroString soft fibers packing 1,280 channels within a 230-µm-diameter fiber, with multi-channel single-unit recording in mouse brain for up to 4 months (Nature, 2025).4
  • BCI implication: stable, high-channel-count, bidirectional (read/write) soft probes with deep-region access are a key enabler for large “brain foundation model” datasets and long-horizon clinical iBCIs, including communication in disorders of consciousness.23

Footnotes

  1. https://news.google.com/rss/articles/CBMie0FVX3lxTE15WEtydDlPMVJnVGczSlJYSFhZQXY2YUdkLVh4OUFMN2hHOTcyakdnVFVVU2NMamJ1X2xQbmJvZDhadk5zMlR5VF9xLVdSNDFfLURBMExuMDg0aUEwa1B1em9qemJ6YjlDSmpBc0tLMGoyNDRYOXNiNFFESQ?oc=5 ↩ ↩2 ↩3 ↩4

  2. https://doi.org/10.1101/2025.04.24.25326126 ↩ ↩2 ↩3 ↩4 ↩5 ↩6 ↩7

  3. https://www.businesswire.com/news/home/20250422988411/en/Axoft-Successfully-Completes-First-Four-Cases-of-First-in-Human-Clinical-Study-of-its-Ultrasoft-High-Density-Brain-Computer-Interface ↩ ↩2

  4. https://www.nature.com/articles/s41586-025-09481-2 ↩

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