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Early interfaced neural activity from chronic amputated nerves.

Garde K, Keefer E, Botterman B, Galvan P, Romero MI - Front Neuroeng (2009)

Bottom Line: Direct interfacing of transected peripheral nerves with advanced robotic prosthetic devices has been proposed as a strategy for achieving natural motor control and sensory perception of such bionic substitutes, thus fully functionally replacing missing limbs in amputees.Multi-electrode arrays placed in the brain and peripheral nerves have been used successfully to convey neural control of prosthetic devices to the user.Non-restrictive electrode arrays placed in the path of regenerating nerve fibers allowed the recording of action potentials as early as 8 days post-implantation with high signal-to-noise ratio, as long as 3 months in some animals, and with minimal inflammation at the nerve tissue-metal electrode interface.

View Article: PubMed Central - PubMed

Affiliation: Department of Plastic Surgery, University of Texas Southwestern Medical Center Dallas, TX, USA.

ABSTRACT
Direct interfacing of transected peripheral nerves with advanced robotic prosthetic devices has been proposed as a strategy for achieving natural motor control and sensory perception of such bionic substitutes, thus fully functionally replacing missing limbs in amputees. Multi-electrode arrays placed in the brain and peripheral nerves have been used successfully to convey neural control of prosthetic devices to the user. However, reactive gliosis, micro hemorrhages, axonopathy and excessive inflammation currently limit their long-term use. Here we demonstrate that enticement of peripheral nerve regeneration through a non-obstructive multi-electrode array, after either acute or chronic nerve amputation, offers a viable alternative to obtain early neural recordings and to enhance long-term interfacing of nerve activity. Non-restrictive electrode arrays placed in the path of regenerating nerve fibers allowed the recording of action potentials as early as 8 days post-implantation with high signal-to-noise ratio, as long as 3 months in some animals, and with minimal inflammation at the nerve tissue-metal electrode interface. Our findings suggest that regenerative multi-electrode arrays of open design allow early and stable interfacing of neural activity from amputated peripheral nerves and might contribute towards conveying full neural control and sensory feedback to users of robotic prosthetic devices.

No MeSH data available.


Related in: MedlinePlus

Minimal inflammation elicited by the multi-electrode array. (A) Schematic of the multi-electrode array mounted in the nerve guide showing the sectioning planes (a-horizontal; b-coronal) used for analysis. Representative coronal (B) and horizontal (C) tissue sections show highly localized ED-1 immunolabeling around the electrodes. (D) Quantification of ED-1+ cellular thickness in such areas revealed a slight but significant increase in the inflammatory response of animals with chronic nerve injuries compared to acute implanted animals. Scale bars = 100 μm (B) and 50 μm (C). NF = nerve fascicle.
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Figure 4: Minimal inflammation elicited by the multi-electrode array. (A) Schematic of the multi-electrode array mounted in the nerve guide showing the sectioning planes (a-horizontal; b-coronal) used for analysis. Representative coronal (B) and horizontal (C) tissue sections show highly localized ED-1 immunolabeling around the electrodes. (D) Quantification of ED-1+ cellular thickness in such areas revealed a slight but significant increase in the inflammatory response of animals with chronic nerve injuries compared to acute implanted animals. Scale bars = 100 μm (B) and 50 μm (C). NF = nerve fascicle.

Mentions: The presence of cells at the tissue-electrode interface suggested some degree of inflammation. To evaluate such response we visualized activated macrophages by immunodetection of the specific ED-1 marker at both horizontal and coronal planes (Figure 4A). Qualitative analysis revealed a relatively low number of macrophages in the area directly in contact with the electrodes, which marked precisely the localization of the electrodes in the regenerated tissue (Figures 4B,C). The accumulation of macrophages around the electrodes was consistent in all animals and limited to two to five cell layers at the bio-abio interface. Quantification of the inflammation area as determined by the length of ED-1 immunoreactivity from the electrode surface to the last positive cell in cross section, revealed a slightly but significantly larger inflammation around the multi-electrode array in chronically injured animals (30 ± 1 μm) compared to those implanted at the time of injury (20 ± 5 μm; Figure 4D).


Early interfaced neural activity from chronic amputated nerves.

Garde K, Keefer E, Botterman B, Galvan P, Romero MI - Front Neuroeng (2009)

Minimal inflammation elicited by the multi-electrode array. (A) Schematic of the multi-electrode array mounted in the nerve guide showing the sectioning planes (a-horizontal; b-coronal) used for analysis. Representative coronal (B) and horizontal (C) tissue sections show highly localized ED-1 immunolabeling around the electrodes. (D) Quantification of ED-1+ cellular thickness in such areas revealed a slight but significant increase in the inflammatory response of animals with chronic nerve injuries compared to acute implanted animals. Scale bars = 100 μm (B) and 50 μm (C). NF = nerve fascicle.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2691654&req=5

Figure 4: Minimal inflammation elicited by the multi-electrode array. (A) Schematic of the multi-electrode array mounted in the nerve guide showing the sectioning planes (a-horizontal; b-coronal) used for analysis. Representative coronal (B) and horizontal (C) tissue sections show highly localized ED-1 immunolabeling around the electrodes. (D) Quantification of ED-1+ cellular thickness in such areas revealed a slight but significant increase in the inflammatory response of animals with chronic nerve injuries compared to acute implanted animals. Scale bars = 100 μm (B) and 50 μm (C). NF = nerve fascicle.
Mentions: The presence of cells at the tissue-electrode interface suggested some degree of inflammation. To evaluate such response we visualized activated macrophages by immunodetection of the specific ED-1 marker at both horizontal and coronal planes (Figure 4A). Qualitative analysis revealed a relatively low number of macrophages in the area directly in contact with the electrodes, which marked precisely the localization of the electrodes in the regenerated tissue (Figures 4B,C). The accumulation of macrophages around the electrodes was consistent in all animals and limited to two to five cell layers at the bio-abio interface. Quantification of the inflammation area as determined by the length of ED-1 immunoreactivity from the electrode surface to the last positive cell in cross section, revealed a slightly but significantly larger inflammation around the multi-electrode array in chronically injured animals (30 ± 1 μm) compared to those implanted at the time of injury (20 ± 5 μm; Figure 4D).

Bottom Line: Direct interfacing of transected peripheral nerves with advanced robotic prosthetic devices has been proposed as a strategy for achieving natural motor control and sensory perception of such bionic substitutes, thus fully functionally replacing missing limbs in amputees.Multi-electrode arrays placed in the brain and peripheral nerves have been used successfully to convey neural control of prosthetic devices to the user.Non-restrictive electrode arrays placed in the path of regenerating nerve fibers allowed the recording of action potentials as early as 8 days post-implantation with high signal-to-noise ratio, as long as 3 months in some animals, and with minimal inflammation at the nerve tissue-metal electrode interface.

View Article: PubMed Central - PubMed

Affiliation: Department of Plastic Surgery, University of Texas Southwestern Medical Center Dallas, TX, USA.

ABSTRACT
Direct interfacing of transected peripheral nerves with advanced robotic prosthetic devices has been proposed as a strategy for achieving natural motor control and sensory perception of such bionic substitutes, thus fully functionally replacing missing limbs in amputees. Multi-electrode arrays placed in the brain and peripheral nerves have been used successfully to convey neural control of prosthetic devices to the user. However, reactive gliosis, micro hemorrhages, axonopathy and excessive inflammation currently limit their long-term use. Here we demonstrate that enticement of peripheral nerve regeneration through a non-obstructive multi-electrode array, after either acute or chronic nerve amputation, offers a viable alternative to obtain early neural recordings and to enhance long-term interfacing of nerve activity. Non-restrictive electrode arrays placed in the path of regenerating nerve fibers allowed the recording of action potentials as early as 8 days post-implantation with high signal-to-noise ratio, as long as 3 months in some animals, and with minimal inflammation at the nerve tissue-metal electrode interface. Our findings suggest that regenerative multi-electrode arrays of open design allow early and stable interfacing of neural activity from amputated peripheral nerves and might contribute towards conveying full neural control and sensory feedback to users of robotic prosthetic devices.

No MeSH data available.


Related in: MedlinePlus