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Alternating current and infrared produce an onset-free reversible nerve block.

Lothet EH, Kilgore KL, Bhadra N, Bhadra N, Vrabec T, Wang YT, Jansen ED, Jenkins MW, Chiel HJ - Neurophotonics (2014)

Bottom Line: Kilohertz frequency alternating current (KHFAC) produces a safe and reversible nerve block.However, KHFAC-induced nerve block is associated with an undesirable onset response.ACIR may be of great clinical utility in the future.

View Article: PubMed Central - PubMed

Affiliation: Case Western Reserve University , Department of Biology, 2080 Adelbert Road, Cleveland, Ohio 44106-7080, United States.

ABSTRACT
Nerve block can eliminate spasms and chronic pain. Kilohertz frequency alternating current (KHFAC) produces a safe and reversible nerve block. However, KHFAC-induced nerve block is associated with an undesirable onset response. Optical inhibition using infrared (IR) laser light can produce nerve block without an onset response, but heats nerves. Combining KHFAC with IR inhibition [alternating current and infrared (ACIR)] produces a rapidly reversible nerve block without an onset response. ACIR can be used to rapidly and reversibly provide onset-free nerve block in the unmyelinated nerves of the marine mollusk Aplysia californica and may have significant advantages over either modality alone. ACIR may be of great clinical utility in the future.

No MeSH data available.


Related in: MedlinePlus

Alternating current and infrared blocks onset response. (a) Left: Onset response due to KHFAC (top bar) in proximal (top) and distal (bottom) recording electrodes. Middle: (top) Complete suppression of onset response in proximal recording electrode after laser block (bar below top bar; block duration indicated by light shaded rectangle). The onset response continues in the distal recording (bottom). Right panels: Recovery of onset response in both proximal and distal recording electrodes when lasers are off. (b) A second experiment in a different animal. Middle top panel shows suppression of the onset response during laser block (bar below top bar; duration of onset response block indicated by light shaded rectangle). As soon as the laser is turned off, the onset response returns in the proximal recording. (c) (Left) Expanded time scale of outlined left box in part (b). Arrow indicates CAP occurring after the two spikes of the stimulation artifact. (Right) CAP is blocked in the distal recording by laser before and just after KHFAC is applied; arrows point to the times at which the CAP should appear.
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f3: Alternating current and infrared blocks onset response. (a) Left: Onset response due to KHFAC (top bar) in proximal (top) and distal (bottom) recording electrodes. Middle: (top) Complete suppression of onset response in proximal recording electrode after laser block (bar below top bar; block duration indicated by light shaded rectangle). The onset response continues in the distal recording (bottom). Right panels: Recovery of onset response in both proximal and distal recording electrodes when lasers are off. (b) A second experiment in a different animal. Middle top panel shows suppression of the onset response during laser block (bar below top bar; duration of onset response block indicated by light shaded rectangle). As soon as the laser is turned off, the onset response returns in the proximal recording. (c) (Left) Expanded time scale of outlined left box in part (b). Arrow indicates CAP occurring after the two spikes of the stimulation artifact. (Right) CAP is blocked in the distal recording by laser before and just after KHFAC is applied; arrows point to the times at which the CAP should appear.

Mentions: When only KHFAC is applied [Figs. 3(a) and 3(b), left panels], the onset response is visible in both the proximal and distal recordings. When IR is also applied, the onset response is blocked in the proximal recording only [Figs. 3(a) and 3(b), middle panels, shaded rectangles]. The onset response was still present at the distal recording because the onset response’s propagation to that electrode was unaffected by the laser [Figs. 1(d) and 1(e)]. Although the onset response was present in the distal recording, the CAP was blocked by the laser [Fig. 3(c)]. The onset response reappeared proximally as soon as the laser was turned off [Figs. 3(a) and 3(b), right panels]. After ACIR, CAPs were triggered and had the same amplitude as before ACIR, demonstrating its reversibility. ACIR produced complete onset response block in each experiment (). The onset response, which has previously been shown to be variable over time,5 was not identical before, during, and after block, but the block of the onset response was always complete.


Alternating current and infrared produce an onset-free reversible nerve block.

Lothet EH, Kilgore KL, Bhadra N, Bhadra N, Vrabec T, Wang YT, Jansen ED, Jenkins MW, Chiel HJ - Neurophotonics (2014)

Alternating current and infrared blocks onset response. (a) Left: Onset response due to KHFAC (top bar) in proximal (top) and distal (bottom) recording electrodes. Middle: (top) Complete suppression of onset response in proximal recording electrode after laser block (bar below top bar; block duration indicated by light shaded rectangle). The onset response continues in the distal recording (bottom). Right panels: Recovery of onset response in both proximal and distal recording electrodes when lasers are off. (b) A second experiment in a different animal. Middle top panel shows suppression of the onset response during laser block (bar below top bar; duration of onset response block indicated by light shaded rectangle). As soon as the laser is turned off, the onset response returns in the proximal recording. (c) (Left) Expanded time scale of outlined left box in part (b). Arrow indicates CAP occurring after the two spikes of the stimulation artifact. (Right) CAP is blocked in the distal recording by laser before and just after KHFAC is applied; arrows point to the times at which the CAP should appear.
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Related In: Results  -  Collection

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f3: Alternating current and infrared blocks onset response. (a) Left: Onset response due to KHFAC (top bar) in proximal (top) and distal (bottom) recording electrodes. Middle: (top) Complete suppression of onset response in proximal recording electrode after laser block (bar below top bar; block duration indicated by light shaded rectangle). The onset response continues in the distal recording (bottom). Right panels: Recovery of onset response in both proximal and distal recording electrodes when lasers are off. (b) A second experiment in a different animal. Middle top panel shows suppression of the onset response during laser block (bar below top bar; duration of onset response block indicated by light shaded rectangle). As soon as the laser is turned off, the onset response returns in the proximal recording. (c) (Left) Expanded time scale of outlined left box in part (b). Arrow indicates CAP occurring after the two spikes of the stimulation artifact. (Right) CAP is blocked in the distal recording by laser before and just after KHFAC is applied; arrows point to the times at which the CAP should appear.
Mentions: When only KHFAC is applied [Figs. 3(a) and 3(b), left panels], the onset response is visible in both the proximal and distal recordings. When IR is also applied, the onset response is blocked in the proximal recording only [Figs. 3(a) and 3(b), middle panels, shaded rectangles]. The onset response was still present at the distal recording because the onset response’s propagation to that electrode was unaffected by the laser [Figs. 1(d) and 1(e)]. Although the onset response was present in the distal recording, the CAP was blocked by the laser [Fig. 3(c)]. The onset response reappeared proximally as soon as the laser was turned off [Figs. 3(a) and 3(b), right panels]. After ACIR, CAPs were triggered and had the same amplitude as before ACIR, demonstrating its reversibility. ACIR produced complete onset response block in each experiment (). The onset response, which has previously been shown to be variable over time,5 was not identical before, during, and after block, but the block of the onset response was always complete.

Bottom Line: Kilohertz frequency alternating current (KHFAC) produces a safe and reversible nerve block.However, KHFAC-induced nerve block is associated with an undesirable onset response.ACIR may be of great clinical utility in the future.

View Article: PubMed Central - PubMed

Affiliation: Case Western Reserve University , Department of Biology, 2080 Adelbert Road, Cleveland, Ohio 44106-7080, United States.

ABSTRACT
Nerve block can eliminate spasms and chronic pain. Kilohertz frequency alternating current (KHFAC) produces a safe and reversible nerve block. However, KHFAC-induced nerve block is associated with an undesirable onset response. Optical inhibition using infrared (IR) laser light can produce nerve block without an onset response, but heats nerves. Combining KHFAC with IR inhibition [alternating current and infrared (ACIR)] produces a rapidly reversible nerve block without an onset response. ACIR can be used to rapidly and reversibly provide onset-free nerve block in the unmyelinated nerves of the marine mollusk Aplysia californica and may have significant advantages over either modality alone. ACIR may be of great clinical utility in the future.

No MeSH data available.


Related in: MedlinePlus