Reanimation of the paralyzed human larynx with an implantable electrical stimulation device.
OBJECTIVE
Electrical stimulation of the posterior cricoarytenoid muscle, when paced with inspiration, offers a physiological approach to restore ventilation in bilateral laryngeal paralysis without any of the disadvantages associated with conventional treatment.


METHODS
A prospective study of six patients.


METHODS
The patients were successfully implanted with an Itrel II stimulator (Medtronic, Inc). In postoperative sessions, stimulated vocal fold abduction, patient ventilation, and voice were assessed and compared with preoperative values.


RESULTS
The optimum stimulus paradigm was a 1- to 2-second train of 1-millisecond pulses delivered at a frequency of 30 to 40 Hz and amplitude of 2 to 7 V. Posterior cricoarytenoid stimulation produced a large dynamic abduction (3.5-7 mm) in three patients and moderate abduction (3 mm) in a fourth patient. The fifth patient showed a large but delayed response of 4 mm to stimulation with some lateralization of the vocal fold. In the sixth patient, stimulated abduction was noted on device implantation but was lost postoperatively. All five patients with stimulated abduction postoperatively met the ventilatory criteria for decannulation, and three patients subsequently had decannulation. Long-term stimulation of the posterior cricoarytenoid muscle had no appreciable effect on voice quality.


CONCLUSIONS
Electrical stimulation of the posterior cricoarytenoid muscle shows potential as an improved therapy for bilateral vocal fold paralysis.
Zealear
David L
DL
Department of Otolaryngology-Head & Neck Surgery, Vanderbilt University Medical School, Medical Center North S2100, Nashville, TN 37232, USA. david.zealear@vanderbilt.edu
Billante
Cheryl R
CR
Courey
Mark S
MS
Netterville
James L
JL
Paniello
Randal C
RC
Sanders
Ira
I
Herzon
Garrett D
GD
Goding
George S
GS
Mann
Wolf
W
Ejnell
Hasse
H
Habets
Alfons M M C
AM
Testerman
Roy
R
Van de Heyning
Paul
P
D000328:Adult; D000368:Aged; D004599:Electric Stimulation Therapy / Q000295:instrumentation; D004576:Electromyography; D005260:Female; D006801:Humans; D007320:Inspiratory Capacity; D007821:Laryngeal Muscles / Q000294:innervation / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009058:Mouth Breathing; D011446:Prospective Studies; D019736:Prostheses and Implants; D014826:Vocal Cord Paralysis / Q000503:physiopathology / Q000628:therapy*; D014827:Vocal Cords / Q000503:physiopathology