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Home / Equine Research Bank / Ir Vet J / Correlation of the Havemeyer endoscopic laryngeal grading sy...
Irish veterinary journal2009; 62(5); 334-338; doi: 10.1186/2046-0481-62-5-334

Correlation of the Havemeyer endoscopic laryngeal grading system with histopathological changes in equine Cricoarytenoideus dorsalis muscles.

Abstract: The establishment of a single validated endoscopic laryngeal grading system for assessing recurrent laryngeal neuropathy (RLN) is desirable to facilitate direct comparisons between the findings of different clinical and research groups worldwide. The objective of this study was to assess the relationship between the Havemeyer endoscopic laryngeal grading system and histopathological changes consistent with RLN in the left cricoarytenoideus dorsalis (CAD) muscle of horses of different breeds with a full range of clinical severities of RLN, i.e., from normal endoscopic laryngeal function to complete laryngeal hemiplegia. Endoscopic grading of laryngeal function of 22 horses was performed using the Havemeyer endoscopic laryngeal grading system. A biopsy sample of the left CAD muscle was obtained from each horse, either at post mortem examination (n = 16), or during routine laryngoplasty surgery (n = 6). A semi-quantitative histopathological scoring system was used to grade the severity of histopathological lesions consistent with RLN in the left CAD muscle of each horse. A significant positive correlation (rs = 0.705, p < 0.001) was found between the Havemeyer grades and sub-grades of laryngeal function and the semi-quantitative assessment of histopathological lesions consistent with RLN in the left CAD muscle. However, a wide spread of muscle histopathological scores was obtained, particularly from horses with Havemeyer sub-grades II.1, III.1 and III.2. In conclusion, the Havemeyer endoscopic laryngeal grading system was found to broadly correlate with histopathological changes consistent with RLN in equine cricoarytenoideus dorsalis muscle.
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Publication Date: 2009-05-01 PubMed ID: 21851734PubMed Central: PMC3113812DOI: 10.1186/2046-0481-62-5-334Google Scholar: Lookup
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  • Journal Article

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.

The study examines a potentially consistent method, the Havemeyer endoscopic laryngeal grading system, for comparing across different research projects on recurrent laryngeal neuropathy (RLN) in horses. The research found a significant positive correlation between Havemeyer endoscopic laryngeal grades and histopathological changes in the horses’ laryngeal muscles, suggesting potential accuracy and reliability in using the Havemeyer system.

Objective and Approach

  • The research aimed at assessing the relationship between Havemeyer endoscopic laryngeal grading system and histopathological changes in horses’ cricoarytenoideus dorsalis (CAD) muscles.
  • This aim was motivated by the need for a universally accepted endoscopic laryngeal grading system that could facilitate comparisons between the findings of different research and clinical groups studying RLN worldwide.

Study Methodology

  • The study used a sample of 22 horses of different breeds and different levels of severity of RLN, ranging from normal function to complete laryngeal hemiplegia.
  • The researchers performed an endoscopic grading of laryngeal function in each horse using the Havemeyer grading system.
  • Additionally, a biopsy of the left CAD muscles was taken from each horse, either post-mortem or during regular laryngoplasty surgery.
  • Finally, a semi-quantitative histopathological scoring system was applied to grade the severity of histopathological changes in the left CAD muscles that were consistent with RLN.

Results and Conclusion

  • A significant positive correlation was observed between the Havemeyer grading and the semi-quantitative assessment of histopathological changes associated with RLN in the left CAD muscle.
  • That said, the study also found a considerable spread of muscle histopathological scores within certain Havemeyer sub-grades (II.1, III.1, and III.2), indicating further research would be beneficial.
  • Despite this, the research concluded that the Havemeyer endoscopic laryngeal grading system could be broadly indicative of histopathological changes consistent with RLN in horses’ CAD muscles, suggesting potential application in future research endeavors.

Cite This Article

APA
Collins N, Milne E, Hahn C, Dixon P. (2009). Correlation of the Havemeyer endoscopic laryngeal grading system with histopathological changes in equine Cricoarytenoideus dorsalis muscles. Ir Vet J, 62(5), 334-338. https://doi.org/10.1186/2046-0481-62-5-334

Publication

Irish veterinary journal
ISSN: 0368-0762
NlmUniqueID: 0100762
Country: Ireland
Language: English
Volume: 62
Issue: 5
Pages: 334-338

Researcher Affiliations

Collins, N
  • The Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush Veterinary Centre, Roslin, Midlothian, EH25 9RG, Scotland. niamhlynne@hotmail.com.
Milne, E
    Hahn, C
      Dixon, P

        References

        This article includes 26 references
        1. Anderson LJ. A study of some muscles of the equine larynx and soft palate.. PhD thesis. Massey University, New Zealand; 1984.
        2. Brakenhoff JE, Holcombe SJ, Hauptman JG, Smith HK, Nickels FA, Caron JP. The prevalence of laryngeal disease in a large population of competition draft horses.. Vet Surg 2006 Aug;35(6):579-83.
          doi: 10.1111/j.1532-950X.2006.00192.xpubmed: 16911159google scholar: lookup
        3. Cahill JI, Goulden BE. Equine laryngeal hemiplegia. Part I. A light microscopic study of peripheral nerves.. N Z Vet J 1986 Oct;34(10):161-9.
          doi: 10.1080/00480169.1986.35334pubmed: 16031224google scholar: lookup
        4. Cahill JI, Goulden BE. Equine laryngeal hemiplegia. Part II. An electron microscopic study of peripheral nerves.. N Z Vet J 1986 Oct;34(10):170-5.
          doi: 10.1080/00480169.1986.35335pubmed: 16031225google scholar: lookup
        5. Cahill JI, Goulden BE. Equine laryngeal hemiplegia. Part IV. Muscle pathology.. N Z Vet J 1986 Nov;34(11):186-90.
          doi: 10.1080/00480169.1986.35343pubmed: 16031233google scholar: lookup
        6. COLE CR. Changes in the equine larynx associated with laryngeal hemiplegia.. Am J Vet Res 1946 Apr;7:69-77.
          pubmed: 21024753
        7. Derksen FJ, Stick JA, Scott EA, Robinson NE, Slocombe RF. Effect of laryngeal hemiplegia and laryngoplasty on airway flow mechanics in exercising horses.. Am J Vet Res 1986 Jan;47(1):16-20.
          pubmed: 3946898
        8. Dixon PM, McGorum BC, Railton DI, Hawe C, Tremaine WH, Pickles K, McCann J. Laryngeal paralysis: a study of 375 cases in a mixed-breed population of horses.. Equine Vet J 2001 Sep;33(5):452-8.
          doi: 10.2746/042516401776254790pubmed: 11558739google scholar: lookup
        9. Dixon PM. Endoscopic grading systems for laryngeal paralysis-6 grade system. Proceedings of a workshop on equine recurrent laryngeal neuropathy, Havemeyer Foundation Monograph Series No. 11 Newmarket, R&W Publications; 2003; pp. 26–27.
        10. Dixon PM, Robinson NE, Wade J. Workshop summary. Proceedings of a workshop on equine recurrent laryngeal neuropathy, Havemeyer Foundation Monograph Series No. 11 Newmarket, R&W Publications; 2003; pp. 93–97.
        11. Dubowitz V. Histological and histochemical stains and reactions. Muscle biopsies - a practical approach. 2 London, Bailliere Tindall; 1985; pp. 19–40.
        12. Ducharme NG, Hackett RP, Fubini SL, Erb HN. The reliability of endoscopic examination in assessment of arytenoid cartilage movement in horses. Part II. Influence of side of examination, reexamination, and sedation.. Vet Surg 1991 May-Jun;20(3):180-4.
          doi: 10.1111/j.1532-950X.1991.tb00332.xpubmed: 1853550google scholar: lookup
        13. Ducharme N. 4-grade system for equine laryngeal function. Proceedings of a Workshop on Equine Recurrent Laryngeal Neuropathy, Havemeyer Foundation Monograph Series No. 11 Newmarket, R&W Publications; 2003; pp. 21–23.
        14. Ducharme NG. Upper airway: clinical perspectives. Proceedings of the world equine airway symposium New York, Itaca; 2005; pp. 85–94.
        15. Duncan ID, Griffths IR, McQueen A, Baker GO. The pathology of equine laryngeal hemiplegia.. Acta Neuropathol 1974 Apr 30;27(4):337-48.
          doi: 10.1007/BF00690698pubmed: 4407536google scholar: lookup
        16. Duncan ID, Baker GJ, Heffron CJ, Griffiths IR. A correlation of the endoscopic and pathological changes in subclinical pathology of the horse's larynx.. Equine Vet J 1977 Oct;9(4):220-5.
          doi: 10.1111/j.2042-3306.1977.tb04036.xpubmed: 923556google scholar: lookup
        17. Duncan ID, Griffiths IR, Madrid RE. A light and electron microscopic study of the neuropathy of equine idiopathic laryngeal hemiplegia.. Neuropathol Appl Neurobiol 1978 Nov-Dec;4(6):483-501.
          doi: 10.1111/j.1365-2990.1978.tb01358.xpubmed: 745676google scholar: lookup
        18. Duncan ID, Hammang JP. Ultrastructural observations of organelle accumulation in the equine recurrent laryngeal nerve.. J Neurocytol 1987 Apr;16(2):269-80.
          doi: 10.1007/BF01795310pubmed: 3625241google scholar: lookup
        19. Duncan ID, Amundson J, Cuddon PA, Sufit R, Jackson KF, Lindsay WA. Preferential denervation of the adductor muscles of the equine larynx. I: Muscle pathology.. Equine Vet J 1991 Mar;23(2):94-8.
          doi: 10.1111/j.2042-3306.1991.tb02728.xpubmed: 2044516google scholar: lookup
        20. Fleming G. Roaring in Horses (laryngismus paralyticus). London, Balliere, Tindall and Cox; 1889; pp. 1–159.
        21. Griffiths IR. The pathogenesis of equine laryngeal hemiplegia.. Equine Vet J 1991 Mar;23(2):75-6.
          doi: 10.1111/j.2042-3306.1991.tb02722.xpubmed: 2044512google scholar: lookup
        22. Gunn HM. Histochemical observations on laryngeal skeletal muscle fibres in 'normal' horses.. Equine Vet J 1972 Jul;4(3):144-8.
          doi: 10.1111/j.2042-3306.1972.tb03896.xpubmed: 4265667google scholar: lookup
        23. Gunn HM. Further observations on laryngeal skeletal muscle in the horse.. Equine Vet J 1973 Apr;5(2):77-80.
          doi: 10.1111/j.2042-3306.1973.tb03198.xpubmed: 4275248google scholar: lookup
        24. Hackett RP, Ducharme NG, Fubini SL, Erb HN. The reliability of endoscopic examination in assessment of arytenoid cartilage movement in horses. Part I: Subjective and objective laryngeal evaluation.. Vet Surg 1991 May-Jun;20(3):174-9.
          doi: 10.1111/j.1532-950X.1991.tb00331.xpubmed: 1853549google scholar: lookup
        25. Lane JG, Bladon B, Little DR, Naylor JR, Franklin SH. Dynamic obstructions of the equine upper respiratory tract. Part 2: comparison of endoscopic findings at rest and during high-speed treadmill exercise of 600 Thoroughbred racehorses.. Equine Vet J 2006 Sep;38(5):401-7.
          doi: 10.2746/042516406778400619pubmed: 16986599google scholar: lookup
        26. Stick JA, Peloso JG, Morehead JP, Lloyd J, Eberhart S, Padungtod P, Derksen FJ. Endoscopic assessment of airway function as a predictor of racing performance in Thoroughbred yearlings: 427 cases (1997-2000).. J Am Vet Med Assoc 2001 Oct 1;219(7):962-7.
          doi: 10.2460/javma.2001.219.962pubmed: 11601794google scholar: lookup

        Citations

        This article has been cited 5 times.
        1. Cercone M, Hokanson CM, Olsen E, Ducharme NG, Mitchell LM, Piercy RJ, Cheetham J. Asymmetric recurrent laryngeal nerve conduction velocities and dorsal cricoarytenoid muscle electromyographic characteristics in clinically normal horses. Sci Rep 2019 Feb 25;9(1):2713.
          doi: 10.1038/s41598-019-39189-zpubmed: 30804428google scholar: lookup
        2. Boyko AR, Brooks SA, Behan-Braman A, Castelhano M, Corey E, Oliveira KC, Swinburne JE, Todhunter RJ, Zhang Z, Ainsworth DM, Robinson NE. Genomic analysis establishes correlation between growth and laryngeal neuropathy in Thoroughbreds. BMC Genomics 2014 Apr 3;15:259.
          doi: 10.1186/1471-2164-15-259pubmed: 24707981google scholar: lookup
        3. Dupuis MC, Zhang Z, Druet T, Denoix JM, Charlier C, Lekeux P, Georges M. Results of a haplotype-based GWAS for recurrent laryngeal neuropathy in the horse. Mamm Genome 2011 Oct;22(9-10):613-20.
          doi: 10.1007/s00335-011-9337-3pubmed: 21698472google scholar: lookup
        4. Al Shehab G, Naji R, Alali F, Alali A, Allowaim A, Almohammed A, Aljasim D, Alkhalifah A, Alhammad YMA, Marzok M, Mohamad ZA, Almuhanna AH. Laryngoscopic evaluation of arytenoid movements in pure Arabian horses. Open Vet J 2025 Jun;15(6):2875-2881.
          doi: 10.5455/OVJ.2025.v15.i6.56pubmed: 41069487google scholar: lookup
        5. Hardwick JL, Ahern BJ, Crawford KL, Allen KJ, Franklin SH. Yearling laryngeal function in Thoroughbreds that underwent a laryngoplasty differs from controls. Equine Vet J 2025 Mar;57(2):431-440.
          doi: 10.1111/evj.14110pubmed: 38847239google scholar: lookup
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