Endoscopy in horses refers to a diagnostic procedure that involves the use of an endoscope, a flexible tube equipped with a camera and light, to visually examine the interior surfaces of equine organs and tissues. This technique is commonly employed to investigate conditions affecting the respiratory tract, gastrointestinal tract, and other internal structures. Endoscopy allows for direct visualization and assessment of abnormalities such as lesions, obstructions, or inflammation. It can also be used to obtain biopsies or remove foreign bodies. This page compiles peer-reviewed research studies and scholarly articles that explore the applications, methodologies, and clinical relevance of endoscopy in equine medicine.
Hahn K, Conze TM, Wollanke B, Distl O, Goehring LS, Witte TS.A 5-month-old draft horse filly was presented with incontinence and severe perivulvar dermatitis, which developed during the previous 2 months. Left-sided ectopic ureter entering in the caudal vaginal lumen, signs of cervix hypoplasia, and urine accumulation in the uterus were found during initial vaginal endoscopy. Therefore, a left ureter-nephrectomy was conducted under general anesthesia. Additionally, a cytogenetic examination was performed, which showed a XO monosomy with a 63,X/64,XX mosaic. This is the first case report presenting a chromosome abnormality in a draft horse filly combine...
Joó K, Povázsai Á, Nyerges-Bohák Z, Szenci O, Kutasi O.It is important to treat the upper and lower respiratory tracts as a single unit, as lower respiratory tract diseases can often cause upper respiratory functional disorders, whereas upper respiratory obstructions could be a factor in lower respiratory problems. The present study aimed to investigate the hypothesis that asthmatic diseases may be an underlying cause of dorsal displacement of the soft palate in horses. Pleasure or sport horses (n = 57) with a history of asthmatic disease were incorporated in the study. All horses were examined in the exacerbation phase of the asthmatic disease. ...
True CK, Dotzel AR.Oral endoscopy is a valuable addition to the equine dental examination process. It enables veterinarians to visualize subtle oral disorders and is a useful client education tool. There are several commercially available oral endoscopic systems on the market. Practitioners can also assemble their own systems. An oral endoscope is used to perform a thorough and systematic oral examination and to visualize normal oral structures as well as oral disorders. It is also used to guide instrument placement during oral surgeries and other dental procedures.
Claffey EF, Ducharme NG.The nasal conchal bullae (dorsal and ventral) are separate, air-filled structures within their respective dorsal and ventral nasal conchae. Computed tomography scans have assisted with the increasing diagnosis of empyema of the nasal conchae. This condition is usually associated with dental or sinus disease. Drainage of affected bullae is considered critical for resolution of clinical signs. The ventral conchal bullae can be easily viewed with a standard 10 mm diameter flexible endoscopy via the middle nasal meatus. This approach can also be used for fenestration of the bullae, using a diode ...
Tallon R, Hewetson M.Equine glandular gastric disease (EGGD) is recognised as a separate entity to equine squamous gastric disease (ESGD) and it is recommended that lesions are graded differently. Currently, no validated scoring system exists for EGGD. Objective: To determine inter-observer reliability of two previously described grading systems for EGGD and to assess if agreement improved with gastroscopy experience, specialist training or familiarity with the descriptive system. Methods: Cross-sectional survey. Methods: A link to an electronic questionnaire containing 20 images of glandular lesions was circulate...
Abdelnaby EA, Emam IA, Salem NY, Ramadan ES, Khattab MS, Farghali HA, Abd El Kader NA.This study aimed to evaluate the use of Doppler ultrasound for determining alterations in uterine thickness and uterine arteries, use of chromohysteroscopy in evaluating endometritis with biopsies, and the impact of endometritis on oxidative and hormonal status. Twenty Arabian mares were divided into control and endometritis groups. Each underwent a physical examination, Doppler ultrasound, chromoendoscopy, and uterine biopsy. Blood samples from each animal were collected for hematologic, hormonal, and oxidative analysis. Results revealed a significant increase in estradiol, malondialdehyde (M...
Scheeren VFC, Sancler-Silva YFR, El-Sheikh Ali H, Kastelic JP, Alvarenga MA, Papa FO.Seminal vesiculitis in stallions reduces fertility and is often underdiagnosed. The most common cause is infection of seminal vesicles by bacteria capable of forming biofilms and a propensity for tissue persistence, for example, Pseudomonas aeruginosa. Achieving a clinical cure is challenging because of a high rate of recurrence. Systemic antibiotic therapy does not reach adequate therapeutic concentrations within the seminal vesicles; one alternative is endoscopy-guided, local antibiotic infusion into the gland lumen, with or without concurrent systemic antibiotics. Current diagnostic and the...
Ponthier J, de la Rebière G, Salciccia A, Deleuze S.In mares, endometrial cysts are associated with endometriosis and can cause maternal recognition failure or compromise and delay pregnancy diagnoses. Historical treatments were invasive and had adverse effects on the endometrium. Hysteroscopically guided laser therapy is easy and effective for endometrial cysts resection, with no deleterious effects for the endometrium. A 110 cm long and 1.0 cm wide endoscope is sterilely introduced in the uterus through the open cervix of an estrous mare after vulvar cleaning. The uterus is slowly infused with less than 1 L of physiologic solution and the las...
Steinmann M, Bezugley RJ, Bond SL, Pomrantz JS, Léguillette R.Capsule endoscopy offers a new method for visualization of the gastrointestinal mucosa in horses where other imaging technologies have diagnostic limitations. Objective: To (1) test the feasibility of using this novel endoscopy capsule to visualize intestinal mucosa in horses, including an objective assessment of image quality, (2) assess how changes in preadministration preparation affect the transit time and the amount of gastrointestinal mucosa visualized, and (3) describe intestinal mucosa lesions in healthy horses. Methods: Five healthy adult horses. Methods: Three protocols were used in ...
Ronaldson HL, Monticelli P, Smith R, Adami C.A 13-year-old Shire horse was anesthetized for an elective orthopedic procedure. During recovery from anesthesia, the occurrence of severe acute dyspnea required a second anesthetic to allow endoscopy-guided nasotracheal intubation. Endoscopic findings were decreased mobility and swelling of the arytenoids with narrowing of the laryngeal aditus. Owing to a dislodgement of the nasotracheal tube during recovery, a third anesthetic was carried out to perform emergency tracheostomy. Recovery from the third anesthetic was long and the horse developed a post-anesthetic myopathy. The clinical conditi...
Miller SM.Endoscopy of thoroughbred (TB) yearlings at public auctions is common in South Africa. Laryngeal function (LF) is a common concern of buyers of young TBs. Cancellation of sale because of LF abnormalities is a concern for both the vendor and the buyer, with recurrent laryngeal neuropathy (RLN) being a common cause of sale cancellation. The aim of this descriptive study was to determine the prevalence of RLN at South African premier TB yearling sales. This study was designed as a retrospective descriptive analysis of upper respiratory tract (URT) endoscopic examinations to determine RLN grade, p...
Svonni E, Andreasson M, Fernström LL, Rydén A, Pringle J, Riihimäki M.Endoscopic examinations are essential for diagnosis and treatment of strangles (S equi infection) in horses. However, even after disinfection, endoscopes may retain viable bacteria or bacterial DNA. Twitches are commonly used during endoscopic examinations and can thus also potentially transmit the organism to other horses. Objective: To evaluate the efficacy of different disinfectant methods to eliminate S equi from experimentally contaminated endoscopes and twitches and the effectiveness of field disinfection of endoscopes used in sampling carriers of S equi. Methods: Experimental contami...
Toft K, Kjeldsen ST, Otten ND, van Galen G, Fjeldborg J, Sinding M, Hansen S.Flexion of the horse's head and neck during dressage riding reduces the pharyngeal lumen with the risk of increased upper airway resistance and upper airway obstructions. According to the Fédération Equestre Internationale, hyperflexion is achieved through force, whereas the position low-deep-round is nonforced. The objectives of this study were to evaluate (1) applied rein tension and (2) dynamic structural disorders in the upper airways in dressage horses in different gaits and different head-neck positions (HNPs). Overground endoscopy (OGE) and rein tension were evaluated in 13 clinically...
Conceição ML, Alonso JM, Alves ALG, Hussni CA, Rodrigues CA, Watanabe MJ.Dorsal displacement of the soft palate (DDSP) usually occurs in athletic adult horses. Congenital DDSP in foals secondary to the persistent frenulum of the epiglottis is rarely observed. The aim of this report was to describe a case of a seven-day-old female neonate Quarter Horse presenting dysphagia, milk reflux through the nostrils and mouth, and expiratory dyspnea since 4 days. Thoracic auscultation was indicative of aspiration pneumonia. Diagnosis of DDSP associated with local inflammation was made after endoscopic examination of upper respiratory tract. Radiographic examination was perfo...
Suen WW, Zedler S, Price R, Maguire T, Halliday C, Rosenblatt AJ, Allavena RE, Owen H, Medina-Torres CE.We describe herein the clinical, endoscopic, computed tomography (CT), pathologic, and microbiologic features of an infection caused by an under-recognized fungal pathogen, , in a 25-y-old Australian Quarter Horse. The horse had a unilateral obstructive nasal mass, resulting in stertor and dyspnea. On endoscopy, the mass was tan, multinodular, and completely obstructed the nasal passage. CT analysis revealed a large, soft tissue-attenuating and partially mineralized mass in the right nasal passage and dorsal-conchofrontal sinus, expanding into adjacent paranasal sinuses with associated bone ly...
Siwinska N, Zak A, Slowikowska M, Krupinska P, Niedzwiedz A.Asthma is one of the most common non-infectious respiratory diseases in horses. Ultrasound examination is a widely available non-invasive additional diagnostic tool. To date, there are no studies focusing on ultrasonographic findings in horses with asthma. The aim of this study was to analyse the prevalence and severity of ultrasound lesions in lung tissue in horses with asthma. Lung ultrasonography was carried out on six healthy horses (controls) and 12 horses with asthma (six with mild and six with severe asthma). The sonographic changes in three lung sections were assessed using a scoring s...
Pozor MA, McCarrel TM, Perez Jimenez EE, Macpherson ML, Kelleman AA, Shelton KE.An 18-year-old Appaloosa stallion presented with a history of ejaculatory dysfunction, which had recently progressed to an inability to ejaculate (anejaculation). Transrectal ultrasound evaluation revealed the presence of a prominent midline cyst of the colliculus seminalis, which was compressing the most terminal parts of the deferent ducts. Both ducts were enlarged and filled with hyperechoic content. The stallion was diagnosed with a complete occlusion of the deferent ducts because of the compression from the midline cyst of the colliculus seminalis. To date, there are no established treatm...
Saito Y, Amaya T.There have been few reports about temporohyoid osteoarthropathy in Japanese horses. The aim of this study was to describe the symptoms and management of temporohyoid osteoarthropathy and to investigate its association with crib-biting behavior, which is commonly observed in Japanese horses. The data concerning case details, signs, diagnosis procedures, treatment, and outcomes were collected retrospectively from the medical records of 11 Thoroughbreds with temporohyoid osteoarthropathy. The trainers and owners were asked whether the horses had displayed crib-biting behavior. Nine of the horses ...
Fretheim-Kelly ZL, Halvorsen T, Clemm H, Roksund O, Heimdal JH, Vollsæter M, Fintl C, Strand E.Dynamic obstructions of the larynx are a set of disorders that occur during exercise in equines and humans. There are a number of similarities in presentation, diagnosis, pathophysiology and treatment. Both equines and humans present with exercise intolerance secondary to dyspnea. During laryngoscopy at rest, the larynx appears to function normally. Abnormalities are only revealed during laryngoscopy at exercise, seemingly triggered by increased ventilatory demands, and quickly resolve after cessation of exercise. Lower airway disease (asthma being the most prevalent condition), cardiac diseas...
Isgren CM, Salem SE, Singer ER, Wylie CE, Lipreri G, Graham RJTY, Bladon B, Boswell JC, Fiske-Jackson AR, Mair TS, Rubio-Martínez LM.Previous studies investigating factors associated with survival following endoscopic treatment of contamination/sepsis of the calcaneal bursa are limited. Objective: To investigate the factors associated with survival in horses with contamination/sepsis of the calcaneal bursae treated endoscopically and to describe the bacterial isolates involved in the synovial infections. Methods: Retrospective analysis of clinical records. Methods: Medical records from 128 horses with contamination/sepsis of the calcaneal bursae treated by endoscopic lavage at seven equine hospitals were reviewed. A follow-...
Jones S, Franklin S, Martin C, Steel C.There is limited knowledge of the breathing strategy and impact on the patency of the upper respiratory tract (URT) in swimming horses. Objective: To describe the respiratory responses and endoscopic appearance of the URT during tethered swimming in horses. Methods: Prospective descriptive study. Methods: Ten race-fit horses, with no history of URT obstruction, were examined during tethered swimming. Endoscopic examination, heart rate, sound recordings and above and below water video recordings were obtained. Plasma lactate concentration was measured before and 5 min after swimming and trache...
Bezdekova B, Wohlsein P, Venner M.The clinical findings and outcome associated with chronic severe equine pyloric lesions have not been well described previously. Objective: To describe the history, clinical signs, endoscopic and ultrasound results, laboratory data, treatment, pathological findings and survival of horses with chronic severe pyloric lesions. Methods: Retrospective case series. Methods: Medical records from horses treated at clinics in Czech Republic and Germany in which chronic severe pyloric lesions were confirmed endoscopically and/or on post-mortem examination were reviewed. Results: Forty-seven horses were ...
Bayly W, Lopez C, Sides R, Bergsma G, Bergsma J, Gold J, Sellon D.Public pressure exists in the United States to eliminate race-day furosemide administration despite its efficacy in decreasing the severity of equine exercise pulmonary hemorrhage (EIPH). No effective alternative prophylaxis strategies have been identified. Objective: To investigate alternative protocols to race-day furosemide that might mitigate EIPH. Methods: Seven fit Thoroughbreds with recent EIPH. Methods: Double-blinded placebo-controlled Latin square crossover using a treadmill followed by a blinded placebo-controlled crossover study at a racetrack. First, horses exercised supramaximall...
Banse HE, Andrews FM.Equine glandular gastric disease (EGGD) is an increasingly recognized disease of the glandular mucosa of the equine stomach. Diagnosis is confirmed by gastric endoscopy and scored based upon one of several different endoscopic scoring systems. Prevalence appears to be variable, depending upon breed and discipline. Primary identified risk factors include exercise frequency, and stress; therefore, management strategies are focused on reducing exercise and stress. Limiting grain intake and increasing pasture turnout may also be helpful preventative measures. Pharmacologic treatment consists prima...
Pouyet M, G Bonilla A.To describe the technique, experience, and limitations of using a 2-mm flexible endoscope to perform standing minimally invasive sinoscopy. Methods: In phases 1 and 2, we used cadaveric heads (ex vivo). In phase 3, we used unaffected horses (in vivo). Methods: Five cadaveric equine skulls in phase 1 and 10 cadaveric equine skulls in phase 2. Six horses older than 5 years in phase 3. Methods: In phase 1, the specimens were used to determine the suitability of the endoscope for sinoscopy and the ideal landmarks to approach the paranasal sinuses through minisinusotomies performed with a 14 gaug...
Pezzanite L, Easley J.Cervical vertebral compressive myelopathy (CVCM) represents the most significant disease of the spinal cord in horses for which surgical treatment is described. Current surgical methods used include ventral interbody fusion with kerf cut cylinders and dorsal laminectomy. Polyaxial pedicle screw and rod constructs and ventral locking compression plating have been introduced in the treatment of equine CVCM and present promising alternative approaches to achieve ventral interbody fusion. Advancements in diagnostic imaging and endoscopy of the cervical vertebral canal may improve reliable preopera...
Morrison ML, Groover E, Schumacher J, Newton J, Pereira MM.Squamous cell carcinoma (SCC) is one of the most common malignant neoplasms in horses, but lingual SCC has seldom been reported. On separate occasions, a 12-year-old American Quarter Horse mare and an 18-year-old American Saddlebred stallion were presented to the Auburn University Large Animal Teaching Hospital for evaluation of weight loss, dysphagia, and ptyalism. Evaluation of each horse included physical examination, skull radiographs, oral examination, complete blood count and serum biochemistry profile, endoscopic evaluation of the mouth, and biopsy of tissue from a lesion found on the t...
Curtiss AL, Parente EJ.To report an epiglottopexy technique for the treatment of epiglottic retroversion (ER) in 2 horses. Methods: Case report. Methods: A 2-year-old thoroughbred gelding and a 6-year-old standardbred gelding, both with ER. Methods: Epiglottic retroversion was diagnosed via exercising endoscopic examination in both horses. Epiglottopexy technique was performed in both cases. Results: Both horses returned to previous racing class within 1 year after surgery. Repeat exercising endoscopy of 1 horse 6 months postoperatively revealed resolution of the ER. Conclusions: Epiglottopexy should be consider...
Bonomo CCM, Michelotto PV, Viccino C, Barussi FCM, Fernandes WR.Pulmonary haemorrhage occurs in sport horses performing high-intensity exercise, but the factors involved in the occurrence of pulmonary haemorrhage in jumping horses have not been elucidated. This study aimed to determine the occurrence of pulmonary haemorrhage and factors involved in competitive jumping horses. Fifty adult jumping horses competing in the city of São Paulo, Brazil, were included. The horses were divided into two groups based on jump height at competition: Low group (LG, n=26), with jump height between 1.00 and 1.20m, and High group (HG, n=24), with jump height between 1.30 a...
Bach FS, Böhler A, Schieder K, Handschuh S, Simhofer H.To evaluate 2 surgical techniques for establishing and/or improving paranasal sinus drainage in cadaver heads and horses with sinusitis and evaluate the feasibility of postoperative transnasal sinus endoscopy. Methods: Ex vivo study (equine cadaver heads) and case series. Methods: Nine adult equine cadaver heads and 8 horses with recurrent sinusitis. Methods: For the ex vivo study, the following procedures were performed on 9 cadaver heads: preoperative and postoperative computed tomography (heads 1-6), endoscopy-guided transnasal conchotomy of the ventral conchal sinus (TCVCS) and surgical en...
Furr MO, Murray MJ.Of 55 horses treated with histamine type 2 (H2) receptor antagonists for gastric ulcers, 32 were examined by gastroendoscopy before and after treatment. Distribution and severity of lesions in the squamous fundus (sf), margo plicatus (mp), glandular fundus (gf), lesser curvature (lc) and cardia (car) were recorded. Severity of the lesions was scored 0-4 (0 = no lesions, 4 = most severe). On initial examination, lesions were most frequently observed at the mp (28/32) and least frequently observed in the gf (5/32). There was endoscopic confirmation of improvement in lesion scores in each region,...
Koch C, Straub R, Ramseyer A, Widmer A, Robinson NE, Gerber V.Although endoscopic scoring of the tracheal septum thickness is used as a diagnostic tool for evaluation of lower airway disease, its clinical relevance and reliability have never been critically assessed in the horse. Objective: To investigate if septum thickness scores (STS) are reliable and serve as a clinically useful indicator of lower airway disease status and/or inflammation. Methods: The variance of STS attributable to the horse, observer and changes over time was determined. The distribution of STS in a population of clinically normal horses and correlations of STS with age, gender, a...
Fischer AT.Recent advances in the use of abdominal ultrasound, endoscopy, laparoscopy, radiography, and peritoneal fluid analysis have contributed to the evaluation of horses with colic. Improved diagnostic capabilities allow earlier surgical intervention when necessary, and this should improve survival rates and the economic aspects of case management.
Freeman DE.The most common disorders of the equine guttural pouches are empyema, tympany, mycosis, and temporohyoid osteoarthropathy. Diagnosis of these conditions is made primarily by imaging with endoscopy, radiographs, computed tomography, and/or MRI. Medical treatment with anti-inflammatories, antimicrobials, and/or antifungals may be successful in some cases, but many of these disorders necessitate surgical intervention. Direct surgical approaches to the guttural pouch are difficult because of their complex anatomy and relationship with important structures, thus precipitating a move toward minimall...
Birks EK, Durando MM, McBride S.EIPH is a condition affecting virtually all horses during intense exercise worldwide. The hemorrhage originates from the pulmonary vasculature and is distributed predominantly bilaterally in the dorsocaudal lung lobes. As the condition progresses, the lung abnormalities extend cranially along the dorsal portions of the lung. An inflammatory response occurs in association with the hemorrhage and may contribute to the chronic sequela. Although conflicting opinions exist as to its affect on performance, it is a syndrome that is thought to increase in severity with age. The most commonly performed...
McGorum BC, Dixon PM.Local transendoscopic endobronchial antigen challenge, which has proved to be a valuable clinical and research technique in the study of human pulmonary hypersensitivity, was evaluated in control and asymptomatic COPD--affected horses. Transendoscopic endobronchial challenges with phosphate-buffered saline (PBS), Micropolyspora faeni extract at 60 and 600 micrograms/ml and mouldy hay extract elicited neutrophilic airway inflammatory responses in control (N = 5-7) and asymptomatic COPD-affected (N = 5-7) horses, as determined by cytological examinations of bronchoalveolar lavage fluid (BALF) ha...
Murray MJ, Grodinsky C.The pH of the gastric mucosal surface and gastric content was measured in 18 foals (mean age: 20 days) and 27 horses (mean age: 2.9 years) with a pH electrode passed through an endoscope biopsy channel. A reference electrode was attached to a shaved area on the neck. pH Measurements of the gastric mucosal surface at the dorsal squamous fundus (SF), squamous mucosa adjacent to the margo plicatus (MP), glandular fundus (GF) and the fluid or feed contents of the stomach were recorded in duplicate for each animal. In adult horses, the SF pH was greatest (5.46 +/- 1.82), with a decreasing pH ventra...
Prange T, Carr EA, Stick JA, Garcia-Pereira FL, Patterson JS, Derksen FJ.A 3-year-old Thoroughbred gelding presented with a history of neurological signs, including incoordination in his hindlimbs, of about 7 months' duration. On initial examination, the horse exhibited ataxia and paresis in all limbs with more severe deficits in the hindlimbs. Cervical radiographs displayed severe osteoarthritis of the articular processes between C5 and C6. On subsequent cervical myelography the dorsal contrast column was reduced by 90% at the level of the intervertebral space between C5 and C6. Cervical vertebral canal endoscopy, including epidural (epiduroscopy) and subarachnoid...
Heath RB, Steffey EP, Thurmon JC, Wertz EM, Meagher DM, Hyyppa T, Van Slyke GL.Sequelae of routine orotracheal intubation under clinical conditions were characterised in 38 healthy horses presented at three veterinary medical teaching hospitals. Four of these were necropsied and their tissues studied histologically. To minimise variation, 30 mm id cuffed silicone endotracheal tubes or Cole cuffless tubes were used in all patients. Fibreoptic endoscopic examination of upper respiratory and tracheal areas was accomplished pre-intubation, immediately post extubation and after 24 h. Endoscopy revealed that intubation was associated with laryngeal and/or tracheal lesions in a...
Anderson BH, Kannegieter NJ, Goulden BE.An endoscopic survey of young race horses was performed to examine the prevalence and character of laryngeal movements during quiet respiration. The main aim was to determine whether those arytenoid movements which could possibly reflect the efficiency of left dorsal cricoarytenoid muscle function changed over a period of time. Of the 452 horses examined, 439 were Thoroughbreds and 23 were Standardbreds, 250 were less than 2 years of age (6-21 months), and 202 were 2 years old. One hundred and nine of these horses were examined again 16 months later. Arytenoid movements were given one of four ...
Desbrosse FG, Perrin R, Launois T, Vandeweerd JM, Clegg PD.To describe endoscopic surgical subtotal resection of the dorsal spinous processes (DSP) and interspinous ligament in horses. Methods: Descriptive clinical study. Methods: Adult horses (n=10) with back pain and impinging dorsal spinous processes Methods: Diseased portions of DSP and interspinous ligament were resected by endoscopic surgery, using Destandau Endospine to create a surgical space and provide triangulation for the endoscope, suction cannula, and surgical instruments. Medical records of 10 horses with pain attributable to DSP pathology treated by endoscopic resection of DSP were rev...
Bell RJ, Kingston JK, Mogg TD.To compare two scoring systems for grading gastric ulcers in adult horses. Methods: Digitised recordings of gastroscopy examinations of 22 horses that were part of a study on prevalence of gastric ulceration in racehorses in New Zealand were reviewed independently by three examiners. All stomachs were graded by each examiner using two different grading systems, the Equine Gastric Ulcer Council (EGUC) system and the Number/Severity (N/S) system. Results: All examiners commented that the EGUC system was quicker and easier to use. There was no significant difference between examiners in the grade...
Raphel CF.A flexible fiberoptic endoscope was used to examine the upper respiratory tract of 479 horses and 41 (8.6%) had abnormalities. Pharyngeal lymphoid hyperplasia (PLH) was found in 141 horses (29.5%). Statistical analysis showed a relationship between the age of the horse and the prevalence of PLH. Sixteen (3.3%), 10 (2.1%), and 6 (1.3%), of the horses had laryngeal hemiplegia, epiglottic entrapment, and dorsal displacement of the soft palate, respectively. There was no association between the age of the horse and the prevalence of any of these abnormalities; nor was there a positive correlation ...
Morris EA, Seeherman HJ.Forty-six racehorses with a history of poor performance underwent endoscopic evaluation of laryngeal and pharyngeal function while exercising on a high-speed treadmill. This evaluation allowed the definitive diagnosis of intermittent or continual upper respiratory tract obstruction as a cause of poor performance, as well as the documentation of the dynamic functional anatomy of the obstruction. Ten of the horses (22%) were determined to have a functional abnormality of the upper respiratory tract. These abnormalities included epiglottic entrapment (1 horse), persistent dorsal displacement of t...
Zebisch A, May A, Reese S, Gehlen H.Hyperflexion, that is the strong deflection of the horse's head, poll and neck, is a prevalent training technique in equitation. Hyperflexion has come under criticism in recent years for being suspected of affecting the horses' well-being contrary to animal welfare. The goal of the present study is a comparison between the impacts of different poll-neck positions on findings in the upper respiratory tract of ridden horses. For this purpose, video recordings of the larynges of 14 horses were taken using an overground endoscope. The videos were recorded at rest and during three different riding ...
Léguillette R, Lavoie JP.To evaluate whether bronchoalveolar lavage (BAL) alters respiratory mechanics of horses with recurrent airway obstruction (ie, heaves) over a 48-hour period. Methods: 6 horses affected with heaves. Methods: Horses were subjected to a complete BAL procedure, which included sedation with xylazine and butorphanol, intratracheal administration of lidocaine, and instillation and aspiration of two 250-mL boluses of saline (0.9% NaCl) solution through an endoscope (study 1). To evaluate the effects of saline solution, horses were subjected to the same procedure without saline solution instillation an...
Elliott S, Cheetham J.Resting endoscopy has commonly been used as a method to predict laryngeal function at exercise. Objective: To perform a meta-analysis to determine the sensitivity and specificity of resting laryngeal endoscopy to predict clinical recurrent laryngeal neuropathy at exercise. Methods: Meta-analysis. Methods: Manuscripts were included if data were available for both resting and exercising airway function on all or a subset of horses. Normal resting endoscopy was defined as laryngeal grades 1 or 2 on a 4-/7-point scale or 1, 2 or 3 on a 5-point scale and normal dynamic endoscopy as a dynamic laryng...
Strand E, Fjordbakk CT, Sundberg K, Spangen L, Lunde H, Hanche-Olsen S.Two genetically and phenotypically distinct horse breeds are used for harness racing in Scandinavia: the Standardbred (SB) and Coldblooded Trotter. These racehorses have identical environmental, management and racing conditions. Therefore, this study was undertaken to identify and compare the relative prevalence of upper respiratory tract (URT) obstructive disorders in these 2 breeds. Objective: To determine whether these 2 phenotypically different breeds of harness racehorses have different predispositions for URT disorders. Methods: Retrospective study of 88 Norwegian Coldblooded Trotters (N...
Holcombe SJ, Derksen FJ, Stick JA, Robinson NE.Dorsal displacement of the soft palate (DDSP) is an intermittent obstructive upper airway condition that occurs in athletic horses during high-intensity exercise. The pathogenesis of this condition is unknown, but may involve epiglottic hypoplasia, malformation, or neuromuscular dysfunction. In this paper, we report on investigations into the pathophysiology of DDSP. In 3 separate experiments, Standardbred horses were exercised on a high-speed treadmill at speeds corresponding to 50, 75 and 100% of maximum heart rate. The upper airway was evaluated by videoendoscopy and measurement of tracheal...
Ducharme NG, Hackett RP, Fubini SL, Erb HN.Twenty Thoroughbred and Standardbred horses underwent endoscopic evaluation of arytenoid cartilage movement twice within 1 week. Each time, a flexible endoscope was passed without sedation through the right nostril and the left nostril, and through the right nostril 5 minutes after administration of xylazine hydrochloride (0.55 mg/kg or 1.1 mg/kg intravenously). Laryngeal cartilage movement was videorecorded. All videotaped images were reviewed by three veterinarians and subjectively placed in one of four grades. The intraobserver agreement rate varied from 52.6% for examination under sedation...
Voss SJ, McGuinness DH, Weir W, Sutton DGM.The role of the equine gastrointestinal microbiota in the pathogenesis of equine glandular gastric disease (EGGD) is poorly understood. To investigate whether the glandular gastric microbiota is altered in horses with EGGD. Prospective longitudinal study. Five Thoroughbred racehorses from one training center underwent gastroscopy as part of poor performance investigation. Samples were taken from EGGD lesions and adjacent normal mucosa using sheathed transendoscopic cytology brushes and frozen at -80°C. DNA was extracted for 16S rRNA sequencing, and sequences compared against a database to gen...
Smith BL, Aguilera-Tejero E, Tyler WS, Jones JH, Hornof WJ, Pascoe JR.To develop a bronchoscopic map of the equine respiratory tree, the major airways of the lungs of 6 healthy Thoroughbred horses were systematically explored with a flexible fibreoptic endoscope through a tracheostomy while the horses were sedated in stocks. With the carina as the reference point, measurements were made of distances to the branches of the major airways using markers on the shaft of the endoscope. All branches were explored until the narrowing of their diameters prevented further advancement of the endoscope. Positions of origins of branches from the parent bronchus were recorded...
McGivney CL, Sweeney J, Gough KF, Hill EW, Katz LM.We hypothesised that grade/appearance for upper respiratory tract (URT) disorders identified at the first overground endoscopy (OGE) examination would vary at subsequent examinations. Objective: To compare OGE examinations from horses evaluated on at least two occasions under similar exercise conditions without treatment intervention. Methods: Retrospective cohort. Methods: Pre-exercise and exercising OGE recordings from Thoroughbred horses undergoing multiple examinations under similar exercise conditions were reviewed, with the first two recordings for each horse statistically evaluated. Pai...
Rossignol F, Vitte A, Boening J, Maher M, Lechartier A, Brandenberger O, Martin-Flores M, Lang H, Walker W, Ducharme NG.To describe the clinical experience with standing laryngoplasty in a series of horses mostly nonracing. Methods: Case series. Methods: Seventy-one client-owned horses. Methods: Medical records (April 2008-February 2014) of horses treated by standing laryngoplasty for abnormal respiratory noise and or poor performance were reviewed. Horses were included if they had a diagnosis of idiopathic right or left recurrent laryngeal neuropathy confirmed by videoendoscopy. All horses underwent a unilateral laryngoplasty with a unilateral or bilateral ventriculectomy or ventriculocordectomy. Follow-up end...
Nixon AJ.An arthroscopic procedure for examination of the digital flexor tendons and tendon sheath was developed in 16 equine limbs and 12 horses. Distension of the tendon sheath and insertion of the arthroscope was accomplished through a cul-de-sac on the palmar or plantar surface of the tendon sheath 1 to 2 cm palmar or plantar to the digital neurovascular structures and between the annular ligament and proximal digital annular ligament. A single arthroscope entry point allowed examination of all regions of the tendon sheath cavity and most surfaces of the digital flexor tendons within the sheath. Di...
Wysocka B, Kluciński W.The aim of the present study was to use endoscopic evaluation to compare the grade of accumulation of discharge in the lower airways of horses with recurrent airway obstruction (RAO) and inflammatory airway disease (IAD), and to estimate the usefulness of endoscopic evaluation in differential diagnosis of these diseases. Endoscopic evaluation consists of: the amount of discharge in the lower part of the trachea and tracheal bifurcation, and the assessment of tracheal septum thickness. This study was performed on 248 horses, 10 were healthy, 97 were diagnosed as RAO, and 141 were diagnosed as I...
Kelly PG, Reardon RJ, Johnston MS, Pollock PJ.Endoscopic examination of Thoroughbred (TB) yearlings is performed routinely to determine the suitability of horses for racing and to ensure that the conditions of sale are satisfied. However, previous research has demonstrated that resting endoscopic examination can be inaccurate in the diagnosis of functional pathology of the upper portion of the respiratory tract (URT). Objective: To investigate the feasibility of performing dynamic overground endoscopy in a group of TB yearlings and to compare the results of resting and dynamic endoscopic examination of the URT. Methods: Prospective cohort...
Cruz VC, Sommardahl CS, Chapman EA, Fry MM, Schumacher J.A 12-year-old 500-kg (1,100-lb) American Quarter Horse mare was evaluated because of chronic mucopurulent, bloody discharge from the left nostril, inspiratory dyspnea, and respiratory noise. Results: The horse had severe inspiratory dyspnea and stertorous respiration with no airflow from the left nostril. A temporary tracheostomy was performed. Endoscopy revealed a tan mass protruding from the left middle nasal meatus into the left common nasal meatus; it extended caudally into the nasopharynx and around the caudal edge of the nasal septum into the right nasal cavity. Radiographically, a soft ...
Perkins JD, Salz RO, Schumacher J, Livesey L, Piercy RJ, Barakzai SZ.The extent to which variability affects endoscopic grading of arytenoid cartilage movement is uncertain. Objective: To determine the observer and within horse variability of grading arytenoid cartilage movement in horses during resting endoscopic examination, using a 7-grade system. Methods: Endoscopic recordings of the upper respiratory tract made at rest in 270 draught horses were reviewed independently by 2 veterinarians to assess interobserver variability when scoring horses' laryngeal function with a 7-grade system. Grading was repeated by both examiners in 80 randomly selected recordings...
Ramzan PH, Parkin TD, Shepherd MC.There has been much research directed at potential causative agents and the epidemiology of lower respiratory tract disease (LRTD), but few reports of the clinical progression and outcome. Objective: To define clinical features of LRTD in racehorses, including association with age and average duration of disease, through the analysis of endoscopic data. Methods: A retrospective analysis of records from a single training yard of endoscopic examinations undertaken over a 2-year period was performed. Horses were subjected to regular endoscopic examination for a variety of reasons, and all horses ...
