Premium
Treatment of spasmodic dysphonia with a neuromodulating electrical implant
Author(s) -
Pitman Michael J.
Publication year - 2014
Publication title -
the laryngoscope
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.181
H-Index - 148
eISSN - 1531-4995
pISSN - 0023-852X
DOI - 10.1002/lary.24749
Subject(s) - cadaveric spasm , stimulation , medicine , neuromodulation , larynx , implant , lead (geology) , functional electrical stimulation , surgery , anesthesia , physical medicine and rehabilitation , audiology , geomorphology , geology
Objectives/Hypothesis To investigate the feasibility of an implantable electrical stimulation device to treat spasmodic dysphonia (SD) by neuromodulation of the muscle spindle gamma loop. Study Design Prospective case series. Method Five subjects underwent daily stimulation of the left thyroarytenoid muscle (TA) below the level of α‐motor neuron activation (AMNA) for 5 consecutive days. Professional and patient voice evaluations were performed. Transcartilagenous placement of an implantable stimulation device lead was investigated in anesthetized porcine and cadaveric human models. Results Three of 5 subjects improved in all categories of evaluation. One subject improved in three of four categories. These four subjects described significant carryover of effect after treatment. The fifth subject evidenced improvement until contracting an upper respiratory infection on day 3. Transcartilagenous electrode placement into the porcine TA with muscle stimulation was successful. The electrode lead was passed from the cadaveric larynx to the mastoid tip in the subplatysma layer with an absence of tension. Conclusion The symptoms of SD improve after electrical stimulation of the TA at levels below AMNA. This is likely through neuromodulation of the muscle spindle gamma loop. Implantation of an electrode into the TA with a postauricular implanted stimulator is feasible with modifications of an already existing device. With further investigation, such a device has the potential to deliver an alternative treatment for SD. Level of Evidence 4, Laryngoscope , 124:2537–2543, 2014