Laryngeal Reinnervation Using a Split-Hypoglossal Nerve Graft in a Canine Model

Chambers, Kyle J.; Song, Phil Hyun; Randolph, Gregory W.; Hartnick, Christopher J.

doi:10.1001/jamaoto.2015.0929

Cited by 4 publications

(3 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The hypoglossal nerve carries motor axons to and proprioceptive dendrites from the intrinsic and extrinsic muscles of the tongue, as well as axons exiting at C1 traveling to geniohyoid and thyrohyoid 36 . Iatrogenic hypoglossal transection or palsy in humans and experimental transection in animals is not consistently associated with poor tongue base retraction, or even symptoms of dysphagia [37][38][39][40][41] . Some have linked hypoglossal nerve transection to decreased oropharyngeal pressures, but these studies involved transections of axons to geniohyoid and therefore do not assess swallowing function in lesions targeting the lingual muscles alone 42 .…”

Section: Discussionmentioning

confidence: 99%

XROMM and diceCT reveal a hydraulic mechanism of tongue base retraction in swallowing

Orsbon

Gidmark

Gao

et al. 2020

Sci Rep

View full text Add to dashboard Cite

During primate swallowing, tongue base retraction (tBR) drives the food bolus across the oropharynx towards the esophagus and flips the epiglottis over the laryngeal inlet, protecting against penetration and aspiration of food into the airway. Despite the importance of tBR for swallowing performance, the mechanics of tBR are poorly understood. Using biplanar videoradiography (XRoMM) of four macaque monkeys, we tested the extrinsic muscle shortening hypothesis, which posits that shortening of the hyoglossus and styloglossus muscles pulls the tongue base posteriorly, and the muscular hydrostat or intrinsic tongue muscle hypothesis, which suggests that, because the tongue is composed of incompressible fluid, intrinsic muscle shortening increases tongue length and displaces the tongue base posteriorly. our data falsify these hypotheses. instead we suggest a novel hydraulic mechanism of tBR: shortening and rotation of suprahyoid muscles compresses the tongue between the hard palate, hyoid and mouth floor, squeezing the midline tongue base and food bolus back into the oropharynx. our hydraulic mechanism is consistent with available data on human tongue swallowing kinematics. Rehabilitation for poor tongue base retraction might benefit from including suprahyoid muscle exercises during treatment. Retraction of the tongue base against the posterior pharyngeal wall is vital a part of swallowing in mammals, including humans 1-4 but how this retraction happens is not well understood. Two mechanisms have been hypothesized. The extrinsic muscle shortening hypothesis posits that contraction of the hyoglossus and styloglossus muscles pulls the tongue base posteriorly 4-9. In support of this hypothesis, the lines of action of the styloglossus and hyoglossus muscles both have posteriorly-oriented components and these muscles are active during swallowing in many mammals, including humans 9-13. The muscular hydrostat or intrinsic tongue muscle hypothesis suggests that, because the tongue is largely composed of incompressible fluid, reduction in tongue base width due to contraction of the transversely oriented intrinsic tongue muscles must be associated with increases in posterior tongue length, and hence tongue base retraction (TBR) 6,14,15. In support of this mechanism, dynamic magnetic resonance imaging (MRI) of humans during swallowing reveals increases in posterior tongue length and depth that are hypothesized to be caused by decreases in tongue width 6-8. Despite widespread acceptance of these two hypotheses, both mechanisms rest on untested assumptions. Contraction (shortening) of styloglossus, palatoglossus, and hyoglossus muscles during swallowing, which is central to the extrinsic muscle shortening hypothesis, has not yet been demonstrated. Although these muscles are active during swallowing 9,10,16 , muscle activity need not be associated with muscle shortening: claims of muscle function require measurements of both muscle activity and muscle velocity 17-20. Moreover, styloglossus, palatoglossus and hyoglossus muscles inse...

show abstract

Section: Discussionmentioning

confidence: 99%

XROMM and diceCT reveal a hydraulic mechanism of tongue base retraction in swallowing

Orsbon

Gidmark

Gao

et al. 2020

Sci Rep

View full text Add to dashboard Cite

show abstract

“…The neuromuscular organization of the tongue has only been partially described in the literature and the impact of denervation has not been well characterized. The hypoglossal nerve is commonly used as a donor nerve for facial reanimation and is actively being investigated as a possible donor nerve for laryngeal reinnervation . Surgical techniques have been described using both split and full hypoglossal nerve anastomosis but with limited reporting on the changes within the tongue.…”

Section: Discussionmentioning

confidence: 99%

“…The hypoglossal nerve is commonly used as a donor nerve for facial reanimation [6][7][8][9] and is actively being investigated as a possible donor nerve for laryngeal reinnervation. 12,13 Surgical techniques have been described using both split and full hypoglossal nerve anastomosis but with limited reporting on the changes within the tongue. The hypoglossal nerve can also be injured during surgery in the oral cavity and oropharynx or in the submandibular triangle.…”

Section: Discussionmentioning

confidence: 99%

Atrophy of the tongue following complete versus partial hypoglossal nerve transection in a canine model

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

Olfactory-ensheathing cells promote physiological repair of injured recurrent laryngeal nerves and functional recovery of glottises in dogs

Liu

Pan

et al. 2018

Mol Cell Biochem

View full text Add to dashboard Cite

The aim of this study was to investigate whether the transplantation of olfactory-ensheathing cells (OECs) could physiologically repair severely injured recurrent laryngeal nerve (RLN) in dogs. Adult Beagle dogs were surgically introduced with a 10-mm defect in the left RLN and transplanted with a nerve guide (NEUROLAC) containing dog olfactory mucosa-olfactory-ensheathing cells (OM-OECs) in matrigel. The effects of OM-OECs on the morphology, histology, and electrophysiology of the injured RLNs, glottis movement, and voice acoustics were comparatively studied. Two months after transplantation, the normal dogs (group N) had intact left RLNs that contained axons well organized as bundles, transmitted action potentials of high amplitudes without latent phases, and modulated glottis movement to produce normal voices. The RLN-damaged dogs transplanted with OM-OECs (group CTT) had pieces of nerves regenerated in the place of the defects, which contained fewer axons scattered in the internal nerve membrane and wrapped peripherally by the connective tissue, prevented the distal trunk of the defected RLN from shrinking, transmitted action potentials of lower amplitudes with latent phases, and modulated a slightly impaired glottis movement to produce voices with slight differences compared to the N dogs. The RLN-damaged dogs without OM-OECs (group NC) had no nerves generated at the defective or the damaged area, leading to a shrinkage in the enervated distal nerve trunks; a blockage in nerve pulse transit; a paralysis of the left vocal cords; an impaired glottis movement; and abnormal voices. Transplantation of OM-OECs promoted nerve regeneration, and the recoveries of glottises and voices in dogs with RLN injury.

show abstract

Laryngeal Reinnervation Using a Split-Hypoglossal Nerve Graft in a Canine Model

Abstract: This study confirms that a full-hypoglossal or split-hypoglossal nerve graft may restore vocal fold motion, without significant functional morbidity, following RLN section in a canine model.

Cited by 4 publications

References 39 publications

XROMM and diceCT reveal a hydraulic mechanism of tongue base retraction in swallowing

XROMM and diceCT reveal a hydraulic mechanism of tongue base retraction in swallowing

Atrophy of the tongue following complete versus partial hypoglossal nerve transection in a canine model

Olfactory-ensheathing cells promote physiological repair of injured recurrent laryngeal nerves and functional recovery of glottises in dogs

Contact Info

Product

Resources

About