In vitro evaluation of the effect of a prototype dynamic laryngoplasty system on arytenoid abduction

OBJECTIVE To determine the effect of a prototype dynamic laryngoplasty system (DLPS) on arytenoid abduction. STUDY DESIGN In vitro experimental. STUDY POPULATION Ten equine larynges. METHODS Dissected larynges were mounted, and the right arytenoid was maximally abducted for testing. A left-sided laryngoplasty (LP) was performed by using a strand of No. 2 FiberWire and a FASTakII anchor. Phase 1 involved tightening the suture, without the DLPS device in place, in 1-mm increments and acquiring a digital image of the rima glottidis at each increment. Phase 2 involved tying the suture with the DLPS in place at a left to right quotient (LRQ) of 0.7. Digital images were subsequently taken at 3 stages of DLPS activation (0, 25, and 50 or maximal psi) and analysed to calculate LRQ. RESULTS All tests were completed for 9 larynges. In phase 1, a total shortening of 25.89 ± 1.27 mm was possible, which increased the LRQ from 0.59 ± 0.02 to 1.07 ± 0.12. In phase 2, activation of the DLPS increased the LRQ from 0.70 ± 0.05 to 0.97 ± 0.09. This change in LRQ equated to 18.7 mm of shortening on the basis of phase 1 results. The maximum psi of the DLPS achieved was 37.33 ± 5.96. CONCLUSION The DLPS increased the degree of arytenoid abduction in vitro. This change in LRQ equated to 18.7 mm of shortening of the LP suture based on phase 1 results. CLINICAL IMPACT These results support further evaluation of the DLPS to determine the effect of changes in DLPS on airway resistance.

[1]  R. Boston,et al.  In vitro comparison of 3 techniques of prosthesis attachment to the muscular process of the equine arytenoid cartilage , 2017, Veterinary surgery : VS.

[2]  P. Mueller,et al.  Ex Vivo Mechanical Evaluation of a Sternal ZipFix(®) Implant for Prosthetic Laryngoplasty in Horses. , 2016, Veterinary surgery : VS.

[3]  J. M. Lumsden,et al.  Dynamic respiratory endoscopic findings pre- and post laryngoplasty in Thoroughbred racehorses. , 2015, Equine veterinary journal.

[4]  F. Rossignol,et al.  Mechanical comparison of 3 anchoring techniques in the muscular process for laryngoplasty in the equine larynx. , 2015, Veterinary surgery : VS.

[5]  F. Rossignol,et al.  Laryngoplasty in standing horses. , 2015, Veterinary surgery : VS.

[6]  P. Dixon,et al.  A review of equine laryngoplasty complications , 2014 .

[7]  M. Miller,et al.  Maintenance of arytenoid abduction following carbon dioxide laser debridement of the articular cartilage and joint capsule of the cricoarytenoid joint combined with prosthetic laryngoplasty in horses: an in vivo and in vitro study. , 2014, Veterinary journal.

[8]  R. Boston,et al.  In vitro mechanical testing of an alternate laryngoplasty system (ALPS) for horses. , 2012, Veterinary surgery : VS.

[9]  M. Hardcastle,et al.  Clinicopathologic observations on laryngoplasty failure in a horse. , 2012, Veterinary surgery : VS.

[10]  Z. Windley,et al.  In vitro effect of ventriculocordectomy before laryngoplasty on abduction of the equine arytenoid cartilage. , 2011, Veterinary surgery : VS.

[11]  E. Birks,et al.  A modified laryngoplasty approach promoting ankylosis of the cricoarytenoid joint. , 2011, Veterinary surgery : VS.

[12]  T. Witte,et al.  Equine laryngoplasty sutures undergo increased loading during coughing and swallowing. , 2010, Veterinary surgery : VS.

[13]  P. Dixon,et al.  Postoperative race performance is not correlated with degree of surgical abduction after laryngoplasty in National Hunt Thoroughbred racehorses. , 2009, Veterinary surgery : VS.

[14]  A. Dart,et al.  Effect of prosthesis number and position on rima glottidis area in equine laryngeal specimens. , 2009, Veterinary surgery : VS.

[15]  B. Ohnesorge,et al.  Laryngoplasty with metallic implants - biomechanical tension test of the arytenoid and cricoid of the horse using metallic prostheses. , 2009 .

[16]  B. Ahern,et al.  Surgical complications of the equine upper respiratory tract. , 2008, The Veterinary clinics of North America. Equine practice.

[17]  J. Hermanson,et al.  In vitro model for testing novel implants for equine laryngoplasty. , 2008, Veterinary surgery : VS.

[18]  J. Hauptman,et al.  The prevalence of laryngeal disease in a large population of competition draft horses. , 2006, Veterinary surgery : VS.

[19]  S. Scherzer,et al.  Evaluation of a canine cranial cruciate ligament repair system for use in equine laryngoplasty. , 2005, Veterinary surgery : VS.

[20]  B. McGorum,et al.  Long-term survey of laryngoplasty and ventriculocordectomy in an older, mixed-breed population of 200 horses. Part 1: Maintenance of surgical arytenoid abduction and complications of surgery. , 2010, Equine veterinary journal.

[21]  B. M. Kraus,et al.  Laryngoplasty with ventriculectomy or ventriculocordectomy in 104 draft horses (1992-2000). , 2003, Veterinary surgery : VS.

[22]  K. Pickles,et al.  Laryngeal paralysis: a study of 375 cases in a mixed-breed population of horses. , 2010, Equine veterinary journal.

[23]  H. Mohammed,et al.  An in vitro comparison of cordopexy, cordopexy and laryngoplasty, and laryngoplasty for treatment of equine laryngeal hemiplegia. , 2000, Veterinary surgery : VS.

[24]  A. Wilson,et al.  In vitro evaluation of a novel prosthesis for laryngoplasty of horses with recurrent laryngeal neuropathy. , 2000, Equine veterinary journal.

[25]  J. Robertson.  Laryngoplasty: a novel prosthesis. , 2000, Equine Veterinary Journal.

[26]  H. Erb,et al.  The reliability of endoscopic examination in assessment of arytenoid cartilage movement in horses. Part II. Influence of side of examination, reexamination, and sedation. , 1991, Veterinary surgery : VS.

[27]  N. E. Robinson,et al.  Effects of ventriculectomy, prosthetic laryngoplasty, and exercise on upper airway function in horses with induced left laryngeal hemiplegia. , 1988, American journal of veterinary research.

[28]  J. Leslie,et al.  Use of a prosthetic device for surgical correction of laryngeal hemiplegia in horses. , 1970, Journal of the American Veterinary Medical Association.