Retrospective study investigating causes of abnormal respiratory noise in horses following prosthetic laryngoplasty

Abstract

SummaryReasons for performing the study: To investigate causes of respiratory noises in horses following prosthetic laryngoplasty (with or without a ventriculocordectomy) and to examine potential associations between degree of arytenoid abduction and the presence of other upper respiratory tract (URT) abnormalities, including right-sided collapse. Methods: Clinical records and dynamic videoendoscopic recordings were examined from horses presented between 1995 and 2010 for investigation of respiratory noise during exercise, following a prosthetic laryngoplasty (+/-a ventriculocordectomy). Relationships between the degree of left arytenoid cartilage abduction and the presence of other URT disorders were investigated. Results: Thirty horses matched the inclusion criteria. All horses had previously undergone a prosthetic laryngoplasty in different hospitals and in 63% (19/30) of these horses a left-sided ventriculocordectomy had also been performed. The majority of cases (87%) had multiple respiratory abnormalities and only 13% had a single URT disorder. Palatal dysfunction was the most common diagnosis (83%), followed by axial deviation of the aryepiglottic folds (60%) and vocal cord collapse (43%). The right arytenoid cartilage was fully abducted in all cases and no statistically significant correlation between the degree of left arytenoid abduction and any other URT disorders was detected. Conclusions: Multiple forms of dynamic URT disorders were diagnosed in horses that presented with abnormal respiratory noise following laryngoplasty. There was no association between degree of left arytenoid abduction and other URT abnormalities. Furthermore, horses with suboptimal left arytenoid cartilage abduction were not predisposed to right-sided laryngeal collapse. Clinical relevance: Our results demonstrate the fundamental role of dynamic endoscopy in correctly diagnosing dynamic airway collapse in horses that have undergone surgical treatment of the upper respiratory tract.

Dynamic respiratory endoscopic findings pre‐ and post laryngoplasty inThoroughbred racehorses

“…Almost half of the cases (48%) had ADAF post operatively concurring with the reported prevalence rates of 34-60% post LP [5][6][7]. Interestingly, horses were significantly more likely to have ADAF post LP compared with preoperatively, suggesting the surgical procedure may have a causative role in the development of ADAF, or that onset of the disease process occurs in the time frame between both exercising examinations.…”

Serial evaluation of resting and exercising overground endoscopic examination results in young Thoroughbreds with no treatment intervention

“…Numerous URT abnormalities showed weak‐to‐negligible agreement in disorder grade/appearance between putatively identical OGE examinations, with conditions such as PI, MDAF, epiglottic grade and iDDSP (at all exercise stages) variable in the direction of the change in grade/appearance. Previous publications have also demonstrated changes in URT abnormalities between OGE examinations, although surgical treatment conducted between examinations and/or undiagnosed pre‐existing or newly developed URT disease(s) were hypothesised to induce these changes . Duration of time between OGE examinations in this study did not significantly affect variability for the majority of URT disorders.…”

Assessment of dynamic upper respiratory tract function in the equine athlete

“…Recently a high prevalence of DDSP has also been noted in horses that have previously undergone a prosthetic laryngoplasty, although the cause remains unclear (Compostella et al . ; Barnett et al . ).…”