Auricular Vagus Nerve Stimulation
Auricular vagus nerve stimulation modulates the body’s autonomic nervous system by electrical pulses
Auricular vagus nerve stimulation has a low side effect profile and produces a long-lasting pain reduction
Auricular vagus nerve stimulation increases the patients’ well-beeing while maintaining full mobility
Many diseases manifest as a (chronic) dysregulation of the activating (sympathetic) and regenerative (parasympathetic) arms of the autonomic nervous system. This reflects in various symptoms such as chronic pain.
The Vagus Nerve holds a key role in the parasympathetic nervous system, controlling regenerative processes in the body. It is involved in the regulation of internal organs, the heart beat, the blood pressure, and the immune system.
An electrical stimulation of sensory Vagus Nerve fibers via small needle electrodes in the auricle activates specific brainstem structures with a subsequent therapeutic effect. By personalized stimulation patterns, this effect can be optimized for each individual patient.
Auricular Vagus Nerve Stimulation boosts parasympathetic activity, initiates regeneration, and reduces pain. By this, a sustainable therapeutic effect can be reached, without the side effects coming with pharmaceuticals.
The Vagus Nerve
The Vagus Nerve is the major constituent of the parasympathetic nervous system. Together with the sympathetic nervous system it plays an important role in continuously regulating vital body functions like heart rate, blood perfusion, and immune response. The Vagus Nerve slows down and regenerates the system.
As one of the twelve cranial nerves in the human body, the Vagus Nerve does not only transmit information from the brain to the organs, but also communicates the actual state of these organs to the brain. In fact, 80% of all fibers in the Vagus Nerve are such afferent / sensory fibers. This feedback is of major importance for the body’s homeostasis.
The Vagus Nerve supplies thoracic and abdominal cavities such as the esophagus, lower airways, heart, aorta, and the entire gastrointestinal tract (1). In addition, the Vagus Nerve sends afferent / sensory fibers to the external auditory channel and the auricle (2), which have been shown to project to the nucleus of the solitary tract in the brainstem (3).
The Vagus Nerve fibers in the concha of the auricle can be located easily by finding blood vessels wiring in parallel (4, 5). By the solely afferent / sensory innervation of the auricle, a direct influence on effector organs, and thus side effects, can be reduced.
The therapeutic action of Auricular Vagus Nerve Stimulation in pain treatment is based on the masking of pain by the electrical stimulation pulses, the activation of inhibiting pain control systems, and the release of neurotransmitters, such as endorphins (6, 7). In parallel, an improved autonomic control can facilitate therapeutic effects and let them sustaine (8).
Sustainable therapeutic effects of Auricular Vagus Nerve Stimulation have already been shown in several clinical studies.
Pain reduction, increased well-being, increased mobility, and increased sleep quality were observed in patients with chronic low back pain and cervical syndrome (6, 7).
In patients suffering from chronic intermittent claudication (peripheral arterial disease) a significant increase of pain-free walking distance was shown (9).
Positive effects of Auricular electrical stimulation on postoperative acute pain could be demonstrated in patients undergoing tonsillectomy and laparoscopic nephrectomy (10, 11).
In contrast to other therapeutic options, such as opioids or invasive spinal cord stimulation, Auricular Vagus Nerve Stimulation provides a minimal-invasive, non-pharmacological, and sustainable therapy for acute and chronic pain patients.
(1) E. Kaniusas et al. Front Neurosci 13(854): 1-23, 2019.
(2) E.T. Peuker and T.J. Filler. Clin Anat 15: 35-37, 2002.
(3) H.R. Berthoud and W.L. Neuhuber. Auton Neurosc Basic 85: 1-17, 2000.
(4) P. Carmeliet und M. Tessier-Lavigne. Nature 436(7048): 193-200, 2005.
(5) E. Kaniusas, G. Varoneckas, B. Mahr und J.C. Széles. IEEE Trans on Instr and Meas 60(10): 3253-3258, 2011.
(6) S.M. Sator-Katzenschlager, J.C. Széles, G. Scharbert et al. Anesth Analg 97: 1496-1473, 2003.
(7) S.M. Sator-Katzenschlager, G. Scharbert, S.A. Kozek-Langenecker et.al. Anesth Analg 98: 1359-1364, 2004.
(8) S. Kampusch, F. Thürk, E. Kaniusas und J.C. Széles. IEEE Sensors Applications Symposium: 79-84, 2015.
(9) T. Payrits, A. Ernst, E. Ladits et al. Zentralblatt Chirurgie 136: 431-435, 2011. (10) R. Likar, H. Jabarzadeh, I. Kager et al. Schmerz 21: 154-159, 2007.
(11) H. Kager, R. Likar, H. Jabarzadeh et al. Acute Pain 11: 101-106, 2009.