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Home / Equine Research Bank / J Vet Intern Med / Pathological classification of equine recurrent laryngeal ne...
Journal of veterinary internal medicine2018; 32(4); 1397-1409; doi: 10.1111/jvim.15142

Pathological classification of equine recurrent laryngeal neuropathy.

Abstract: Recurrent Laryngeal Neuropathy (RLN) is a highly prevalent and predominantly left-sided, degenerative disorder of the recurrent laryngeal nerves (RLn) of tall horses, that causes inspiratory stridor at exercise because of intrinsic laryngeal muscle paresis. The associated laryngeal dysfunction and exercise intolerance in athletic horses commonly leads to surgical intervention, retirement or euthanasia with associated financial and welfare implications. Despite speculation, there is a lack of consensus and conflicting evidence supporting the primary classification of RLN, as either a distal ("dying back") axonopathy or as a primary myelinopathy and as either a (bilateral) mononeuropathy or a polyneuropathy; this uncertainty hinders etiological and pathophysiological research. In this review, we discuss the neuropathological changes and electrophysiological deficits reported in the RLn of affected horses, and the evidence for correct classification of the disorder. In so doing, we summarize and reveal the limitations of much historical research on RLN and propose future directions that might best help identify the etiology and pathophysiology of this enigmatic disorder.
Copyright © 2018 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
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Publication Date: 2018-04-24 PubMed ID: 29691904PubMed Central: PMC6060325DOI: 10.1111/jvim.15142Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research article explores the pathological classification of Recurrent Laryngeal Neuropathy (RLN), a common degenerative disorder in tall horses which affects their laryngeal nerves and ultimately their performance and welfare. The study examines the neuropathological changes and electrophysiological deficits in affected horses, aiming to clarify the classification and thereby facilitate further research into its cause and treatment.

Recurrent Laryngeal Neuropathy (RLN)

  • RLN is a degenerative disorder prevalent in tall horses, specifically impacting their recurrent laryngeal nerves (RLn). This disorder leads to inspiratory stridor at exercise because of intrinsic laryngeal muscle paresis – a condition where muscles become weak or paralyzed.
  • Impact of this disorder on the affected horses is significant, leading not only to exercise intolerance and laryngeal dysfunction but often to serious outcomes such as surgical intervention, retirement, or euthanasia. There are also financial and welfare implications associated with the disorder.

Classification of RLN

  • Despite speculation, there is no clear consensus on RLN’s primary classification due to conflicting evidence. It is uncertain whether RLN is a distal axonopathy – a disease affecting the nerve axons, a primary myelinopathy – a disease affecting the protective layer around nerve fibers, or whether it’s a mononeuropathy affecting one nerve or a polyneuropathy affecting many nerves.
  • This lack of defined classification impedes not only the understanding of the disorder but also hampers etiological (causal) and pathophysiological research.

Neuropathological Changes and Electrophysiological Deficits

  • The study examines the changes at a cellular level (neuropathological changes) and the impact of these changes on the electrical functioning of the nerves (electrophysiological deficits) within the RLNs of horses affected by RLN.

Future Directions for RLN Research

  • The paper also critically evaluates the historical research on RLN, highlighting its limitations and proposing new directions for future research. Better understanding of the disorder’s pathological classification could help identify its etiology (causation) and pathophysiology (disease mechanisms), ultimately aiding in its treatment and prevention.

Cite This Article

APA
Draper ACE, Piercy RJ. (2018). Pathological classification of equine recurrent laryngeal neuropathy. J Vet Intern Med, 32(4), 1397-1409. https://doi.org/10.1111/jvim.15142

Publication

Journal of veterinary internal medicine
ISSN: 1939-1676
NlmUniqueID: 8708660
Country: United States
Language: English
Volume: 32
Issue: 4
Pages: 1397-1409

Researcher Affiliations

Draper, Alexandra C E
  • Comparative Neuromuscular Disease Laboratory, Department is Clinical Science and Services, Royal Veterinary College, London, United Kingdom.
Piercy, Richard J
  • Comparative Neuromuscular Disease Laboratory, Department is Clinical Science and Services, Royal Veterinary College, London, United Kingdom.

MeSH Terms

  • Animals
  • Cranial Nerve Diseases / classification
  • Cranial Nerve Diseases / pathology
  • Cranial Nerve Diseases / veterinary
  • Horse Diseases / classification
  • Horse Diseases / pathology
  • Horses
  • Recurrent Laryngeal Nerve / pathology

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