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Cited by 543Wireless Power Transfer SystemsWireless Body Area NetworksNeuroscience and Neural Engineering

Wireless power transfer to deep-tissue microimplants

Open access
Ho, John S., Yeh, Alexander J., Neofytou, Evgenios, Kim, Sanghoek, Tanabe, Yuji, Patlolla, Bhagat, Beygui, Ramin E., Poon, Ada S. Y.·2014·Proceedings of the National Academy of Sciences
DOI 10.1073/pnas.1403002111PMC PMC4050616
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Abstract

Progress in semiconductor technology paved the way for devices at the scale of a millimeter or less (“microimplants”), but the miniaturization of the power source remains challenging. Although wireless powering has been demonstrated, energy transfer beyond superficial depths in tissue has so far been limited by large coils (at least a centimeter in diameter) unsuitable for a microimplant. Here, we show that this limitation can be overcome by a method, termed midfield powering, to create a high-energy density region deep in tissue. We demonstrate wireless power transfer to a millimeter-sized device implanted five centimeters inside the chest on the surface of the heart—a depth once thought out of reach for wireless power transmission.

Integrity signals

Registry

Crossref · 10.1073/pnas.1403002111

Cites

34 of 34 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

4 of 41 cited sources checked · 0 supported · 0 flagged · accuracy not yet measured

  • Findingcitation

    Using the Debye dispersion model for each tissue type, the peak efficiency was found to occur at 1.6 GHz.

    “Using the Debye dispersion model for each tissue type (24), the peak efficiency was found to occur at 1.6 GHz.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [24] 24. Gabriel S, Lau RW, Gabriel C (1996) The dielectric properties of biological tissues: III. Parametric models for the dielectric spectrum of tissues. Phys Med Biol 41(11): 2271-2293. source

      Section 2 describes tissue-specific parameters for predicting dielectric behavior and introduces the Debye equation, but says the tissue spectrum is more appropriately described by multiple Cole-Cole dispersions. Section 3 says a four Cole-Cole model was adopted throughout the study. The citation is attached to the model description, not the subsequent 1.6 GHz efficiency finding. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
  • Findingown data
    § Wireless power transfer to deep-tissue microimplants

    A method termed midfield powering can create a high-energy density region deep in tissue inside of which the power-harvesting structure can be made extremely small.

    “Here, we show that this limitation can be overcome by a method, termed midfield powering, to create a high-energy density region deep in tissue inside of which the power-harvesting structure can be made extremely small.”
    Quote in the paperSubstantial claim
  • Findingnone given
    § Wireless power transfer to deep-tissue microimplants

    A patterned metal plate induces spatially confined and adaptive energy transport through propagating modes in tissue, unlike conventional near-field coils whose coupling is limited by exponential field decay.

    “Unlike conventional near-field (inductively coupled) coils, for which coupling is limited by exponential field decay, a patterned metal plate is used to induce spatially confined and adaptive energy transport through propagating modes in tissue.”
    Quote in the paperSubstantial claim
  • Findingown data
    § Wireless power transfer to deep-tissue microimplants

    The midfield powering method can power a microimplant (2 mm, 70 mg) capable of closed-chest wireless control of the heart that is orders of magnitude smaller than conventional pacemakers.

    “We use this method to power a microimplant (2 mm, 70 mg) capable of closed-chest wireless control of the heart that is orders of magnitude smaller than conventional pacemakers.”
    Quote in the paperSubstantial claim
  • Findingcitation

    Provided that the fields can be refocused, computational studies show that the performance is insensitive to the fine structure and composition of the intermediate tissue.

    “Provided that the fields can be refocused, computational studies show that the performance is insensitive to the fine structure and composition of the intermediate tissue (30).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [30] 30. Kim S, Ho JS, Chen LY, Poon ASY (2012) Wireless power transfer to a cardiac implant. Appl Phys Lett 101:073701. source
  • May combine two claims. 17
  • The quote only partly states this claim. 1
  • Classified as probably not a substantial claim. 5

  • May combine two claims.

    Premisecitation
    § Wireless power transfer to deep-tissue microimplants

    Existing energy-harvesting methods (thermoelectric, piezoelectric, biopotential, or glucose) are anatomically specific and yield power densities too low (<0.1 μW/mm2) for a microimplant.

    “However, these methods are anatomically specific and, in their existing forms, yield power densities too low (<0.1 μW/mm 2 ) for a microimplant.”
    Quote in the paperSubstantial claim2 of 5 sources checked
    • cites [4] 4. Hochbaum AI, et al. (2008) Enhanced thermoelectric performance of rough silicon nanowires. Nature 451(7175):163-167. source
    • cites [5] 5. Xu S, Hansen BJ, Wang ZL (2010) Piezoelectric-nanowire-enabled power source for driving wireless microelectronics. Nat Commun 1:93. source

      The introductory passage following the Abstract says earlier piezoelectric nanogenerators produced too little power for conventional components. It does not establish that thermoelectric, biopotential, or glucose-based methods are anatomically specific, nor does it give the <0.1 μW/mm² threshold or assess whether those methods can power a microimplant. The Discussion reports this paper’s generator output in mW/cm³, a different measure. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
    • cites [6] 6. Wang ZL, Wu W (2012) Nanotechnology-enabled energy harvesting for self-powered micro-/nanosystems. Angew Chem Int Ed Engl 51(47):11700-11721. source
    • cites [7] 7. Dagdeviren C, et al. (2014) Conformal piezoelectric energy harvesting and storage from motions of the heart, lung, and diaphragm. Proc Natl Acad Sci USA 111(5): 1927-1932. source
    • cites [8] 8. Mercier PP, Lysaght AC, Bandyopadhyay S, Chandrakasan AP, Stankovic KM (2012) Energy extraction from the biologic battery in the inner ear. Nat Biotechnol 30(12): 1240-1243. source

      The passage on implantable energy sources (section labelled Abstract; page unavailable) says thermoelectric and piezoelectric approaches require externally worn apparatuses for mammalian applications, and describes limitations of reported biofuel cells. It does not give a <0.1 μW/mm² power-density threshold for those methods or establish that all four named methods are anatomically specific and too low-power for a microimplant. (LLM, conf=0.84)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation
    § Wireless power transfer to deep-tissue microimplants

    Near-field methods do not address key challenges to powering a microimplant: weak coupling between extremely asymmetric source and receiver structures, dissipative and heterogeneous tissue, and regulatory power thresholds for general safety.

    “Though well-suited for large devices and prostheses (21,22), near-field methods do not address key challenges to powering a microimplant: weak coupling between extremely asymmetric source and receiver structures (23), dissipative and heterogeneous tissue (24), and regulatory power thresholds for general safety (25).”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [23] 23. Kim S, Ho JS, Poon ASY (2013) Midfield wireless powering of subwavelength au- tonomous devices. Phys Rev Lett 110:203905. source
    • cites [24] 24. Gabriel S, Lau RW, Gabriel C (1996) The dielectric properties of biological tissues: III. Parametric models for the dielectric spectrum of tissues. Phys Med Biol 41(11): 2271-2293. source

      The model and figure in Section 5 report permittivity and conductivity for 17 distinct tissues, supporting the cited point that tissue has differing, dissipative electrical properties. The paper does not assess whether near-field methods can address those properties when powering a microimplant. Citation (24) is attached to the tissue-property point, not the separately cited coupling or regulatory claims. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
    • cites [25] 25. Institute of Electrical and Electronic Engineers (2005) IEEE Standard for Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz. IEEE Standard C95.1 (IEEE, New York).

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingown data
    § Wireless power transfer to deep-tissue microimplants

    With exposure levels below human safety thresholds, milliwatt levels of power can be transferred to a deep-tissue (>5 cm) microimplant for both complex electronic function and physiological stimulation.

    “With exposure levels below human safety thresholds, milliwatt levels of power can be transferred to a deep-tissue (>5 cm) microimplant for both complex electronic function and physiological stimulation.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The porcine tissue and simulated tissue models used in the experiments adequately represent human tissue for the power transfer and safety conclusions.

  • May combine two claims.

    Findingown data
    § Wireless power transfer to deep-tissue microimplants

    Using a patterned metal plate to control the near field, milliwatt levels of power transfer to a miniaturized coil deep in heterogeneous tissue (>5 cm) are demonstrated with exposure levels below safety thresholds for humans, enabling a microimplant capable of delivering controlled electrical pulses to nearly anywhere in the body.

    “Using a patterned metal plate to control the near field, we demonstrate milliwatt levels of power transfer to a miniaturized coil deep in heterogeneous tissue (>5 cm), with exposure levels below safety thresholds for humans; this enables us to power a microimplant capable of delivering controlled electrical pulses to nearly anywhere in the body.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The porcine tissue and simulated tissue models used in the experiments adequately represent human tissue for the power transfer and safety conclusions.

  • May combine two claims.

    Findingown data

    When coupling 500 mW into tissue, the measured power transferred to the coil was 195 μW for the heart configuration and 200 μW for the brain configuration.

    “When coupling 500 mW into tissue (approximately the output power of cell phones), we measured the power transferred to the coil to be 195 μW for the heart and 200 μW for the brain configurations.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The source and device positions in the porcine tissue configurations represent realistic deep-tissue powering scenarios.

  • May combine two claims.

    Findingown data

    Analysis of fields on the skin surface shows that the evanescent spectrum approximates the theoretical optimum, although the contribution of radiative modes is ∼2× greater owing to the inherent directionality of the planar structure.

    “Analysis of the fields on the surface of the skin shows that the evanescent spectrum approximates the theoretical optimum (Fig. 2B), although the contribution of the radiative modes is ∼2× greater owing to the inherent directionality of the planar structure.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Fig. 2B

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingown data
    § Wireless power transfer to deep-tissue microimplants

    Wireless function was demonstrated by operating the device in human-scale heart and brain environments and by wirelessly regulating cardiac rhythm through a chest wall.

    “We demonstrate wireless function by operating it in human-scale heart and brain environments, and by wirelessly regulating cardiac rhythm through a chest wall.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The rabbit cardiac pacing model is representative of human cardiac pacing for the wireless control claim.

  • May combine two claims. The quote only partly states this claim.

    Findingown data

    If the power coupled into tissue is allowed to meet the maximum permitted level of exposure, 2.2 mW and 1.7 mW can be transferred for the heart and brain configurations, respectively.

    “If the power coupled into tissue is allowed to meet the maximum permitted level of exposure, Fig. 3F shows that 2.2 mW and 1.7 mW can be transferred for the configurations shown in Fig. 3 A and B, respectively.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Fig. 3F

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingown data

    These received power levels are far greater than requirements for advanced integrated circuits; cardiac pacemakers consume ∼8 μW.

    “These levels are far greater than requirements for advanced integrated circuits (Table S1); in comparison, cardiac pacemakers consume ∼8 μW (1, 29).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [1] 1. Chandrakasan AP, Verma N, Daly DC (2008) Ultralow-power electronics for bio- medical applications. Annu Rev Biomed Eng 10:247-274. source
    • cites [29] 29. Wong LSY, et al. (2004) A very low-power CMOS mixed-signal IC for implantable pacemaker applications. IEEE J Solid-State Circuits 39:2446-2456. source

  • May combine two claims.

    Findingown data

    Over an S-shaped trajectory of motion, this adaptation eliminates dark regions that otherwise occur in the static case, indicating a coverage area much wider than that intrinsic to the focal region.

    “Over an S-shaped trajectory of motion, this adaptation eliminates dark regions that otherwise occur in the static case (Fig. 4 C and D), indicating a coverage area much wider than that intrinsic to the focal region (Fig. S5).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Fig. 4 C and D

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Fig. S5

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingown data

    When positioned above tissue, the structure couples power from external circuitry into the tissue volume with high efficiency (>90%), as evidenced by low backside radiation and a pronounced minimum in the scattering spectrum.

    “When positioned above tissue, the structure couples power from the external circuitry into the tissue volume with high efficiency (>90%), as evidenced by both low levels of backside radiation and a pronounced minimum in the scattering spectrum (Fig. S2B).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Fig. S2B

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingnone given

    Using a patterned metal plate placed in close proximity to skin, the output field can be focused to dimensions much smaller than the vacuum wavelength, creating a high-energy density region within which the power-harvesting structure can be made extremely small.

    “Using a patterned metal plate placed in close proximity to skin, the output field can be focused to dimensions much smaller than the vacuum wavelength, creating a highenergy density region within which the power-harvesting structure can be made extremely small.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Cardiac rhythm can be controlled in a fully wireless manner by adjusting the operating frequency; when coincident with the resonant frequency of the circuit, the pulse amplitudes are sufficient to pace the heart, as indicated by the increased rate and regularity of the ECG signal.

    “Cardiac rhythm can be controlled in a fully wireless manner by adjusting the operating frequencywhen coincident with the resonant frequency of the circuit, the pulse amplitudes are sufficient to pace the heart, as indicated by the increased rate and regularity of the ECG signal (Fig. 5D).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Fig. 5D

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • Rests on an assumption: The rabbit cardiac pacing model is representative of human cardiac pacing for the wireless control claim.

  • May combine two claims.

    Findingcitation

    The electrostimulator device is 2 mm in diameter, weighs 70 mg, and is capable of generating 2.4-μJ pulses at rates dependent on the extracted power; its characteristic dimension is at least an order of magnitude smaller than existing commercial pacemakers due to the absence of a battery.

    “The electrostimulator device shown in Fig. 5 A-C is 2 mm in diameter, weighs 70 mg, and is capable of generating 2.4-μJ pulses at rates dependent on the extracted power; its characteristic dimension is at least an order of magnitude smaller than existing commercial pacemakers (29) due to the absence of a battery (Fig. S6B).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [29] 29. Wong LSY, et al. (2004) A very low-power CMOS mixed-signal IC for implantable pacemaker applications. IEEE J Solid-State Circuits 39:2446-2456. source
    • cites Fig. S6B

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Findingnone given

    The minimum power to operate the device is ∼10 μW.

    “The minimum power to operate the device is ∼10 μW.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation
    § Wireless power transfer to deep-tissue microimplants

    Batteries remain a major obstacle to miniaturization because their lifetimes are limited and highly constrained by the available volume, requiring periodic surgical replacement once depleted.

    “Although considerable progress has been made in energy storage technologies, batteries remain a major obstacle to miniaturization (2, 3) because their lifetimes are limited and highly constrained by the available volume, requiring periodic surgical replacement once the unit is depleted.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [2] 2. Iddan G, Meron G, Glukhovsky A, Swain P (2000) Wireless capsule endoscopy. Nature 405(6785):417. source
    • cites [3] 3. Armand M, Tarascon JM (2008) Building better batteries. Nature 451(7179):652-657. source

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning
    § Wireless power transfer to deep-tissue microimplants

    The approach developed here should enable new generations of implantable systems that can be integrated into the body at minimal cost and risk.

    “The approach developed here should enable new generations of implantable systems that can be integrated into the body at minimal cost and risk.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Study design and conductnone given

    All testing procedures and equipment are the same or equivalent to those used to demonstrate safety compliance to international standards for consumer electronics, including cell phones and other wireless equipment.

    “All testing procedures and equipment are the same or equivalent to those used to demonstrate safety compliance to international standards for consumer electronics, including cell phones and other wireless equipment.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationnone given

    Systems based on similar concepts can be applied for any other optical or electrical stimulation task in the body, including neurons or muscle cells; they can also potentially be generalized to networks of individually addressable probes for coordinated mapping and stimulation.

    “Systems based on similar concepts can be applied for any other optical or electrical stimulation task in the body, including neurons or muscle cells; they can also potentially be generalized to networks of individually addressable probes for coordinated mapping and stimulation.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable). May combine two claims.

    Interpretationreasoning

    Because the performance characteristics shown here far exceed requirements for integrated technologies, there are considerable possibilities for new generations of microimplants, including further size reduction to micrometer scales or more sophisticated functions such as real-time monitoring of chronic disease states or closed-loop neural sensing and control.

    “Because the performance characteristics shown here far exceed requirements for integrated technologies (optoelectronics, microelectromechanical systems sensors, and logic units), there are considerable possibilities for new generations of microimplants: the size, for example, can be further reduced to micrometer scales (23) or more sophisticated functions implemented, such as real-time monitoring”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [23] 23. Kim S, Ho JS, Poon ASY (2013) Midfield wireless powering of subwavelength au- tonomous devices. Phys Rev Lett 110:203905. source
20 of 20

  • The paper relies on this without support.

    The porcine tissue and simulated tissue models used in the experiments adequately represent human tissue for the power transfer and safety conclusions.

    “The source and device positions within a porcine tissue volume, shown in Fig. 3 A and B using MRI reconstructions, are separated by at least 5 cm.”
    “To assess the exposure levels induced by power transfer, we operated our source over a simulated tissue volume defined by an anthropomorphic fiberglass shell.”

  • The paper relies on this without support.

    The liquid solution with dielectric properties mimicking muscle tissue adequately represents muscle tissue for efficiency measurements.

    “when transferring power to a device submerged in a liquid solution with dielectric properties mimicking muscle tissue”
    “0.5% saline”

  • The paper relies on this without support.

    The rabbit cardiac pacing model is representative of human cardiac pacing for the wireless control claim.

    “As a demonstration of stimulation capabilities in vivo, we inserted the wireless electrostimulator into the lower epicardium of a rabbit.”
    “Cardiac rhythm can be controlled in a fully wireless manner by adjusting the operating frequencywhen coincident with the resonant frequency of the circuit, the pulse amplitudes are sufficient to pace the heart, as indicated by the increased rate and regularity of the ECG signal (Fig. 5D).”

  • The paper relies on this without support.

    The source and device positions in the porcine tissue configurations represent realistic deep-tissue powering scenarios.

    “The source and device positions within a porcine tissue volume, shown in Fig. 3 A and B using MRI reconstructions, are separated by at least 5 cm.”
4 of 4

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • The proposed inductive coupling links at 13.56 MHz and 40.68 MHz produce SARs 2-3 orders of magnitude below the safety threshold.

    “It is remarkable that unlike prior arts operating at hundreds of MHz4,6,7, the proposed inductive coupling links at 13.56 MHz and 40.68 MHz bands render SARs 2–3 orders of magnitude lower than the safety regulation threshold.”

    From Synchronized Biventricular Heart Pacing in a Closed-chest Porcine Model based on Wirelessly Powered Leadless Pacemakers (2020) · cites this paper as [4]

    The Electromagnetic Region of Operation section identifies this paper’s operating frequency as 1.6 GHz, not 13.56 or 40.68 MHz. The Results report maximum 10-g SARs of 0.89 W/kg and 1.17 W/kg against a 10 W/kg threshold—roughly one order of magnitude lower, not two to three. The cited paper describes a different, higher-frequency system rather than the proposed links. (LLM, conf=0.91)

    Checked by a reasoning model — may be wrong.

    Experimental — accuracy not yet measured

  • Continuous midfield powering has been utilized to power a cardiac implant at a 5 cm range by coupling 500 mW into tissue and achieving nearly 200 μW while remaining below SAR safety thresholds.

    “Continuous midfield powering has been utilized to power a cardiac implant at a 5 cm range by coupling 500 mW into tissue and achieving nearly 200 µW while remaining below SAR safety thresholds19, 20.”

    From Inductively powered wireless pacing via a miniature pacemaker and remote stimulation control system (2017) · cites this paper as [20]

    The Results report 195 µW transferred to a coil in a heart configuration at a source–device separation of at least 5 cm with 500 mW coupled into tissue. The Results also report SAR below the controlled-environment threshold at 500 mW. But these measurements used a porcine-tissue configuration; the separate live-rabbit cardiac-pacing demonstration used 1 W at approximately 4.5 cm, and the cited passages do not establish continuous operation. (LLM, conf=0.84)

    Experimental — accuracy not yet measured

  • Wireless power transfer techniques can shrink the form factor and reduce invasiveness of implantable medical devices.

    “While many remain battery-powered, wireless power transfer techniques can further reduce the form factor and invasiveness of these devices4–10.”

    From Synchronized Biventricular Heart Pacing in a Closed-chest Porcine Model based on Wirelessly Powered Leadless Pacemakers (2020) · cites this paper as [4]

    Experimental — accuracy not yet measured

  • Earlier studies have tested wirelessly powered single-site cardiac pacing in rodent, rabbit, and open-chest porcine models.

    “Prior studies have investigated wirelessly powered single-site cardiac pacing on rodent, rabbit and open-chest porcine models4,5,21.”

    From Synchronized Biventricular Heart Pacing in a Closed-chest Porcine Model based on Wirelessly Powered Leadless Pacemakers (2020) · cites this paper as [4]

  • Inductive power transfer introduces bioengineering challenges due to Specific Absorption Rate limits and minimal size capacity for device implantation.

    “However, inductive power transfer introduces numerous bioengineering challenges due to Specific Absorption Rate (SAR) limits and minimal size capacity for device implantation.”

    From Inductively powered wireless pacing via a miniature pacemaker and remote stimulation control system (2017) · cites this paper as [20]

Cites

Flagged first, then by citations

Research works printed but not linked: 2

  1. JC Schuder, HE Stephenson, JF Townsend, High level electromagnetic energy transfer through a closed chest wall. Inst Radio Engrs Int Conv Record 9, 119–126 (1961).
  2. Institute of Electrical and Electronic Engineers (2005) IEEE Standard for Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields 3 kHz to 300 GHz . IEEE Standard C95.1 (IEEE New York).

Cited by

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Related

Authors
Ho, J. S., Yeh, A. J., Neofytou, E., Kim, S., Tanabe, Y., Patlolla, B., Beygui, R. E., & Poon, A. S. Y.
Affiliations
  • Departments of aElectrical Engineering and
  • Stanford Medicine (US)
ORCID
Venue
Proceedings of the National Academy of Sciences
Publisher
National Academy of Sciences
Published
2014-05-19
Volume
111
Issue
22
Pages
7974-7979
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
DOI
10.1073/pnas.1403002111
PMC
PMC4050616
OpenAlex
W2103709281
Cited by
541
References
29
Citations by year
2026: 24 · 2025: 38 · 2024: 34 · 2023: 40 · 2022: 39 · 2021: 62 · 2020: 48 · 2019: 40 · 2018: 48 · 2017: 65 · 2016: 43 · 2015: 49 · 2014: 10
FWCI
29.55
Type
journal article
Language
en
Update notices
correction (2023-06-20)
Open access
Locations
  • Proceedings of the National Academy of Sciences (publishedVersion)
  • Europe PMC (PubMed Central) (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • eScholarship (California Digital Library) (submittedVersion)
Funders
  • American Heart Association
  • National Defense Science and Engineering Graduate
  • National Institute of Biomedical Imaging and Bioengineering
Topics
  • Physical Sciences › Engineering › Electrical and Electronic Engineering › Wireless Power Transfer Systems
  • Physical Sciences › Engineering › Biomedical Engineering › Wireless Body Area Networks
  • Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neuroscience and Neural Engineering
Keywords
wireless power transfer, inductive coupling, cardiac implantable electronic devices, physiological stimulation, energy density
MeSH terms
Animals, Cerebral Cortex, Electromagnetic Fields, Electronics, Medical, Equipment Design, Heart Ventricles, Humans, Miniaturization, Models, Theoretical, Electric Power Supplies, Rabbits, Semiconductors, Skin, Swine, Prostheses and Implants, Optics and Photonics, Wireless Technology

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Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-11.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-11.

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