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Respiratory system
Published in A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha, Clark’s Procedures in Diagnostic Imaging: A System-Based Approach, 2020
A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha
Thin-section CT is therefore used to examine the skull base, the larynx and the cervical course of the recurrent nerves. The vagus nerves run in the carotid sheath, and the recurrent laryngeal nerves branch off the vagus on the left to pass under the aortic arch and on the right under the subclavian artery, before ascending again to the larynx. CT should therefore extend from the skull base to below the aortic arch.
Noninvasive vagus nerve stimulation in Parkinson’s disease: current status and future prospects
Published in Expert Review of Medical Devices, 2021
Hilmar P. Sigurdsson, Rachael Raw, Heather Hunter, Mark R. Baker, John-Paul Taylor, Lynn Rochester, Alison J. Yarnall
In principle, two types of nVNS devices are commercially available. Transcutaneous auricular VNS (taVNS) is used to stimulate structures of the outer ear such as the tragus and cymba conchae, which are innervated by the auricular branch of the vagus nerve (ABVN) [11]. By contrast, transcutaneous cervical VNS (tcVNS) is delivered via a hand-held device while indirectly stimulating the (left) cervical branch of the vagus nerve within the carotid sheath [12]. A pressing issue is to identify the most optimal stimulation parameters such as the current intensity (milliamps [mA]), frequency (Hertz [Hz]), pulse width (microseconds [µs]), waveform shape (sine, rectangular), cycle duration (on/off periods) and optimal dosage. Stimulation parameters used in studies employing the taVNS device vary widely (readers are referred to as an excellent and comprehensive review by Farmer and colleagues [10]). The majority of studies utilize monophasic or biphasic rectangular pulses, with a pulse width between 200 and 300 μs, current intensity at 0.5 mA, and a frequency of 25 Hz [10].