, Volume 30, Issue 6, pp 714–722 | Cite as

The Physiologic Impact of Unilateral Recurrent Laryngeal Nerve (RLN) Lesion on Infant Oropharyngeal and Esophageal Performance

  • Francois D. H. GouldEmail author
  • Andrew R. Lammers
  • Jocelyn Ohlemacher
  • Ashley Ballester
  • Luke Fraley
  • Andrew Gross
  • Rebecca Z. German
Original Article


Recurrent laryngeal nerve (RLN) injury in neonates, a complication of patent ductus arteriosus corrective surgery, leads to aspiration and swallowing complications. Severity of symptoms and prognosis for recovery are variable. We transected the RLN unilaterally in an infant mammalian animal model to characterize the degree and variability of dysphagia in a controlled experimental setting. We tested the hypotheses that (1) both airway protection and esophageal function would be compromised by lesion, (2) given our design, variability between multiple post-lesion trials would be minimal, and (3) variability among individuals would be minimal. Individuals’ swallowing performance was assessed pre- and post-lesion using high speed VFSS. Aspiration was assessed using the Infant Mammalian Penetration-Aspiration Scale (IMPAS). Esophageal function was assessed using two measures devised for this study. Our results indicate that RLN lesion leads to increased frequency of aspiration, and increased esophageal dysfunction, with significant variation in these basic patterns at all levels. On average, aspiration worsened with time post-lesion. Within a single feeding sequence, the distribution of unsafe swallows varied. Individuals changed post-lesion either by increasing average IMPAS score, or by increasing variation in IMPAS score. Unilateral RLN transection resulted in dysphagia with both compromised airway protection and esophageal function. Despite consistent, experimentally controlled injury, significant variation in response to lesion remained. Aspiration following RLN lesion was due to more than unilateral vocal fold paralysis. We suggest that neurological variation underlies this pattern.


Aspiration Recurrent laryngeal nerve Infant Esophagus Deglutition Deglutition disorders 



We thank the animal care staff in the Comparative Medicine Unit at Northeast Ohio Medical University. We are also grateful for the comments and critiques of the NeoMed Biomechanics Journal Club. This work was supported by NIH DC 009980 to RZG.

Compliance with Ethical Standards

Conflict of interest

None of the authors have any conflict of interest to report.


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Francois D. H. Gould
    • 1
    Email author
  • Andrew R. Lammers
    • 2
  • Jocelyn Ohlemacher
    • 1
  • Ashley Ballester
    • 1
  • Luke Fraley
    • 1
  • Andrew Gross
    • 1
  • Rebecca Z. German
    • 1
  1. 1.Department of Anatomy and NeurobiologyNortheast Ohio Medical UniversityRootstownUSA
  2. 2.School of Health SciencesCleveland State UniversityClevelandUSA

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