4 ms·

Wait, what? A minimally invasive _craniotomy_? Cutting open the skull generally isn't thought to be minimally invasive. Cool technique but a rather crazy title

by 3JPLW 8y ago

Wait, what? A minimally invasive _craniotomy_? Cutting open the skull generally isn't thought to be minimally invasive. Cool technique but a rather crazy title given that the paper barely touches on invasiveness. Much better would be "biocompatible" or "mechanically stable" or "long-lasting."

mattkrause 8y ago
You still need a craniotomy, but the dura remains mostly intact. Rodent dura is a lot thinner than in primates though, so it'll be interesting to see whether it works in larger animals. I'd also like to see some actual data showing that these electrodes last longer. People can keep Utah arrays going for a few years, even though the implantation surgery is more invasive. (craniotomy + duratomy + pneumatic insertion). Still, it's nice to see some innovation that might eventually work in large animals and humans, instead of yet another thing that only works in transgenic mice.
- frisco 8y ago
  Utah arrays overwhelmingly fail within the first year: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4868924/figure/F5/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4868924/figure/...
  - mattkrause 8y ago
    If the array works at all, we've been reliably able to get /something/ for at least a year and sometimes much more, which I guess isn't too inconsistent with that. Still, a lot of our problems haven't been brain-related; instead, there's an infection or mechanical damage to the connector pedestal/wire bundle. I'm not sure that the sewing machine by itself will be able to sidestep those sorts of problems. I would be very happy to see better alternatives. I'm just not ready to switch based on this.
    - 3JPLW 8y ago
      Agreed, I've seen the same. Take that graph with a grain of salt and take a look at the failure modes table below it. Lots of monkey issues (about a quarter) and some totally unrelated things (like experiment termination). Some labs/surgeons/methods have better success than others. The big thing the sewing machine will do is (likely) reduce mechanical strain at the tissue-electrode interface and hopefully improve upon those handful of failures due to scar tissue encapsulation.
    - georgewfraser 8y ago
      I had the same experience in my time at U. Pitt: arrays that worked at all worked for a couple years. I also spent a lot of time talking to people who had implanted Utah arrays at that time, and I found that there was a ton of variability in the details of how people performed the procedure. That was almost 10 years ago, so maybe there’s some stronger best practices now.

by 3JPLW 8y ago

mattkrause 8y ago

You still need a craniotomy, but the dura remains mostly intact. Rodent dura is a lot thinner than in primates though, so it'll be interesting to see whether it works in larger animals. I'd also like to see some actual data showing that these electrodes last longer. People can keep Utah arrays going for a few years, even though the implantation surgery is more invasive. (craniotomy + duratomy + pneumatic insertion). Still, it's nice to see some innovation that might eventually work in large animals and humans, instead of yet another thing that only works in transgenic mice.

frisco 8y ago
Utah arrays overwhelmingly fail within the first year: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4868924/figure/F5/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4868924/figure/...
- mattkrause 8y ago
  If the array works at all, we've been reliably able to get /something/ for at least a year and sometimes much more, which I guess isn't too inconsistent with that. Still, a lot of our problems haven't been brain-related; instead, there's an infection or mechanical damage to the connector pedestal/wire bundle. I'm not sure that the sewing machine by itself will be able to sidestep those sorts of problems. I would be very happy to see better alternatives. I'm just not ready to switch based on this.
  - 3JPLW 8y ago
    Agreed, I've seen the same. Take that graph with a grain of salt and take a look at the failure modes table below it. Lots of monkey issues (about a quarter) and some totally unrelated things (like experiment termination). Some labs/surgeons/methods have better success than others. The big thing the sewing machine will do is (likely) reduce mechanical strain at the tissue-electrode interface and hopefully improve upon those handful of failures due to scar tissue encapsulation.
  - georgewfraser 8y ago
    I had the same experience in my time at U. Pitt: arrays that worked at all worked for a couple years. I also spent a lot of time talking to people who had implanted Utah arrays at that time, and I found that there was a ton of variability in the details of how people performed the procedure. That was almost 10 years ago, so maybe there’s some stronger best practices now.