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.
Holland M, Snyder JR, Steffey EP, Heath RB.Laryngotracheal damage following short-term nasotracheal intubation was studied in 7 healthy horses. A flexible fiberoptic endoscope was used to examine the upper respiratory tract of each horse before nasal intubation with a cuffed silicone endotracheal tube and again at 1 hour, 24 hours, and 48 hours after extubation. Any abnormalities still evident at 48 hours were evaluated at 7 days after extubation. Mucosal damage involved the nasal meatus (5 of 7 horses), the arytenoid cartilages (5 of 7 horses), the trachea (5 of 7 horses), the dorsal pharyngeal recess (4 of 7 horses), the vocal folds ...
Hillidge CJ, Whitlock TW.Post race endoscopy was carried out on 255 two-year-old quarter horses and exercise-induced pulmonary haemorrhage (EIPH) was diagnosed in 166 (65 per cent) of them. Visible epistaxis was seen in a higher proportion of geldings than in either mares or stallions. The prevalence of EIPH was similar in mares (73 per cent) and in geldings (74 per cent). A significantly lower prevalence (49 per cent) was noted in stallions (P less than 0.01). It was concluded that a sex variation in the prevalence of EIPH exists in two-year-old quarter horses.
Campbell-Thompson ML, Brown MP, Slone DE, Merritt AM, Moll HD, Levy M.Gastroenterostomy was performed in 14 foals to treat gastric outflow obstruction caused by advanced gastroduodenal ulcer disease. The onset of excessive salivation and teeth grinding, without response to medical treatment, combined with endoscopic and radiographic evidence of gastric outflow obstruction, were indications for surgical intervention. Successful outcome in 5 foals was attributed to early diagnosis, patient stabilization, early surgical correction, and postoperative management including antibiotics and antiulcer medication.
Bertone JJ, Traub-Dargatz JL, Trotter GW.Endoscopic examination of a 7-year-old gelding with weight loss indicated a palatal defect with a prominent tissue mass at the caudomedial margin of the defect. At necropsy, the condition was determined to be bilateral hypoplasia of the soft palate.
Martin GS, Beadle RE, Haynes PF, Watters JW.The ventral-to-dorsal height of the rima glottidis was measured from lateral pharyngeal radiographs after correction for magnification. The rima glottidis height was used to enlarge accurately endoscopic photographs of 5 horses taken before and after transection of the left recurrent laryngeal nerve. Areas of the rima glottidis and aditus laryngis were measured, using a computerized digitizer. Mean area of the aditus laryngis was 1,908 mm2 before neurectomy and 1,346 mm2 after neurectomy (P = 0.025). Mean area of the rima glottidis was 1,198 mm2 before neurectomy and 805 mm2 after neurectomy (...
Lindsay FE, Clayton HM.Using histological techniques, anatomical dissection, fibre optic endoscopy and radiography, the nasopharynx and larynx of the donkey were examined and described. Compared with horses, donkeys have a much deeper pharyngeal recess extending 4.0-6.0 cm caudally from a constricted orifice, through which it communicates with the nasopharynx. Movements of the membranous lining of the recess reflect pressure changes in the upper airways. A shallow, thumb shaped depression on the rostral face of each vocal fold corresponds in position to the lateral ventricle in the horse. In the donkey, large paired...
Deegen E.With the aid of a flexible glassfibre endoscope, a 300 W cold light source and a special adapted camera, colour photographs of the upper respiratory tract of horses were taken. These pictures served to present especially the disease processes of the different areas of the upper respiratory tract which lead to a constriction of the lumen. These included proliferation in the nose, guttural pouch diseases and larynx diseases such as hemiplegia, subepiglottic cysts, epiglottic entrapment and rostral displacement of the plica palatopharyngica. Furthermore endoscopic findings of changes in the soft ...
Tate LP, Newman HC, Cullen JM, Sweeney C.Laryngeal surgery in the equine is customarily and routinely performed by means of a ventral laryngotomy incision. Such procedures are usually performed under deep general anesthesia with the horse in dorsal recumbency. The objective of this work was to determine the efficacy of an endoscopic approach coupled to a Nd:YAG laser fiber in performing arytenoidectomy. Arytenoidectomy is commonly indicated in the treatment of arytenoid chondritis and in the failure of prosthetic implantation for left laryngeal hemiplegia. This preliminary study was undertaken to determine the feasibility of the endo...
Todhunter RJ, Stick JA, Slocombe RF.The effects of 3 feeding techniques on healing of a cervical esophageal mucosal resection and anastomosis were investigated in 16 horses. Horses were fed a moistened pelleted diet 1 of 3 ways: 1) per os (n = 5), 2) by nasogastric (n = 5) or 3) by esophagostomy tube (n = 6) until the 14th postoperative day. The pelleted diet was then fed orally in all horses until euthanasia on the 60th postoperative day. Immediate postoperative feeding per os was unsatisfactory, as only 2 of 5 horses survived in this group. Endoscopic evaluation revealed that mucosal dehiscence of varying degrees occurred, wit...
Todhunter RJ, Brown CM, Stickle R.Five horses with retropharyngeal (RP) infections had clinical signs of dysphagia and/or dyspnea. Diagnosis was confirmed, using pharyngeal endoscopy and lateral radiography of the pharynx. One horse responded to surgical drainage of a RP abscess and was sound at light work. One horse responded to medical management after the site of infection was surgically explored. Two horses recovered after medical management; the RP abscess of 1 of these 2 horses ruptured spontaneously into the pharynx and the other horse became racing sound. The fifth horse remained dysphagic and had left laryngeal hemipl...
Jann HW, Cook WR.Monopolar electrosurgical cutting was used to correct epiglottal entrapment in 5 horses. The operations were carried out in the conscious animal, using topical anesthesia. The procedure required the use of a coagulation electrode designed specifically for electrosurgery, introduced through the instrument channel of a fiberoptic endoscope. The results were satisfactory and serious complications were not encountered. In 2 horses, excessive submucosal swelling developed at the site of the surgical wound, and the tumefaction took several weeks to subside in one of these horses. In both horses, the...
Sweeney CR, Sweeney RW, Raker CW, Freeman DE.A 3-year-old Thoroughbred filly had a pharyngeal abscess causing obstruction of the upper respiratory tract. Diagnosis was made by a combination of endoscopy, biopsy, cytology, and radiography. Treatment with antimicrobials and analgesics resulted in successful resolution of the abscess.
Goulden BE, Anderson LJ, Cahill JI.An endoscopic survey was performed to assess arytenoid cartilage movement during quiet respiration in 48 Clydesdale horses. Physical characteristics which could influence the length of the recurrent laryngeal nerves were also recorded from these horses and the relationship of these characteristics to the presence of abnormal left arytenoid cartilage movements was assessed statistically. Some degree of abnormal arytenoid movement was observed in 50% of the animals over one year of age. No significant correlation between sex, age, estimated weight, height, or neck length could be found although ...
Brown CM, Slocombe RF, Derksen FJ.A method of fiberoptic gastroduodenoscopy and biopsy was developed for use in large horses. A 275 cm X 13.5 mm fiberendoscope was used to examine the stomach and proximal portion of the duodenum. Food was withheld for 24 to 48 hours before examination. In more than 50 horses, gastric and duodenal structures were easily visualized. A variety of lesions was detected, including parasitic lesions, gastric ulcers, gastric neoplasia, and pyloric stenosis. Mucosal biopsy specimens were obtained in selected cases.
Auer DE, Wilson RG, Groenendyk S.The prevalence of pharyngeal lymphoid hyperplasia in Thoroughbred racehorses in training was investigated using a fibre optic endoscope. Of the 70 horses examined, all but 8 showed evidence of pharyngeal lymphoid hyperplasia and the severity of the pharyngeal changes decreased with age. Two-year old horses had greater pharyngeal lymphoid hyperplasia (p less than 0.05) when compared to all other age groups. More horses (p less than 0.05) with Grade 3 or Grade 4 pharyngeal lymphoid hyperplasia experienced recent mild respiratory disease than did horses with Grade 2 or less pharyngeal lymphoid hy...
Mackey VS, Wheat JD.PLEUROSCOPY is a diagnostic technique in which a flexible
or rigid endoscope is used to examine the pleural space.
Although pleuroscopy is a relatively new technique in equine
medicine, it has been used for some time in human medicine
(Jacobaeus 1910, 1925; Lloyd 1953). It is most often used in
human patients to explore the thoracic cavity of persons with
undiagnosed pleural effusions when more conservative
methods, such as percutaneous lung or pleural biopsy, have
been unsuccessful in providing a diagnosis (Hatch and
Decamp 1966; Decamp, Mosely, Scott and Hatch 1973;
Gwin et a1 1975...
Burrell MH.A group of racehorses in training was examined on several occasions with a fibreoptic endoscope and monitored for viral infection. Only equine herpes virus-2 (EHV-2) infection was detected. Pharyngeal lymphoid hyperplasia (PLH) was present in all horses and decreased in severity with age. There was no association between PLH severity and antibody titres to EHV-1, or with the isolation of EHV-2. Finishing position in races was not affected by PLH severity. Exercise induced pulmonary haemorrhage (EIPH) was evident on 23 out of 49 (47 per cent) examinations after maximal speed training exercise. ...
Mason DK, Collins EA, Watkins KL.An investigation into the incidence of exercise induced pulmonary haemorrhage (EIPH) in thoroughbreds in Hong Kong was carried out between the 1981 and 1983 racing seasons. A total of 1039 post race endoscopic examinations were performed in 1982-1983 and the results indicated that 46.8 per cent of runners had EIPH. This was not statistically different from the percentage of horses showing EIPH during 1981-82 (46.9 per cent). As it had been postulated that dust, especially from straw, could be implicated in lung haemorrhage a proportion of horses were bedded on paper in the 1982-83 season. No s...
Smith KM, Barber SM.A two year old Thoroughbred gelding, presented with guttural pouch hemorrhage, had the internal and external carotid arteries ligated. Guttural pouch mycosis was detected on endoscopic examination. After one month of topical antifungal therapy, the horse was returned and euthanized because of recurrent epistaxis. A bacterial infection of the guttural pouch with associated ulceration and hemorrhage from the maxillary artery was found at necropsy.A two year old grade gelding had ulceration and hemorrhage from the external carotid artery. Utilizing balloon-tipped catheters and arterial ligation, ...
Grabner A.Using a fibreoptic endoscope ("small gastroscope" with outside diameter of 9.3 mm) a simple and sparing inspection of the guttural pouch is performed. The flap-type tube cover is opened by means of medial leverage with a guidance probe shifted through the work duct of the endoscope. The same procedure is used in diagnostic specimen collection and therapeutical measures such as irrigations. Guttural pouch topography and pathological disorders are illustrated by endoscopic photography. The different diseases such as follicular hyperplasia, ascending pharyngeal catarrh, perforating abscesses of t...
Stick JA, Slocombe RF, Derksen FJ, Scott EA.Esophageal healing was studied in 12 ponies after cervical esophagotomy. The esophagus was sutured, feed and water were withheld for 48 hours, and then all ponies were permitted to eat. In group I (n = 6), a longitudinal esophagotomy was made. In group II (n = 6), a rotational esophagotomy was made with the mucosal incision 180 degrees away from the incision in the esophageal muscle. Three ponies in each group were fed a soft diet ad libitum for 9 days, and then were allowed access to hay and grain. The remaining ponies were fed hay and grain. The esophagotomies of all hay-fed ponies dehisced ...
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 ...
Etherington WG, Vasey JR, Horney FD.Two cases of ethmoid hematoma of the equine are reported. Clinically both horses had intermittent unilateral epistaxis unassociated with exercise. In one horse, diagnosis was based on the use of an endoscope for visualization and for biopsy of a mass associated with the ethmoid turbinates. In the other horse, exploratory trephination of the posterior maxillary sinus was necessary to obtain a diagnostic biopsy specimen. Radiography was helpful in the diagnosis of one case. Surgical removal of the mass was attempted in one case. Histological examination of the biopsies was the single most defini...
Speirs VC, van Veenendaal JC, Harrison IW, Smyth GB, Anderson GA, Wilson DV, Gilbo B.Endoscopic examinations of the upper respiratory tract were done on 92 of 314 Standardbred horses that raced one or more times at 4 consecutive, weekly race meetings. Although participation was voluntary, the characteristics of the population of horses examined were not statistically different from those of all horses that raced. No horse showed epistaxis, but 34 (32.4%) examinations of the trachea revealed blood that ranged from a trace in the tracheal mucus to large amounts scattered over the tracheal walls. Forty-four horses exhibited minor degrees of pharyngeal lymphoid hyperplasia, 2 had ...
Raphel CF, Soma LR.Thoroughbred horses (n = 191) were examined with a flexible fiberoptic endoscope within 2 hours of racing on a dirt track; 147 (75.4%) had evidence of exercise-induced pulmonary hemorrhage (EIPH), and 13 (9.0%) had blood at the nostrils. Of 107 Thoroughbreds examined within the same period after breezing, 41 (38.3%) had evidence of EIPH. One horse (2.4%) of this group had blood at the nostrils. Statistical analysis of frequency data showed that a relationship existed between EIPH and the horse's age or distance raced or breezed. Relationship did not exist between EIPH and sex or finishing posi...
Deegen E, Müller P, Petzoldt K.On the basis of cytological similarities in chronic obstructive disease (COPD) in human beings and in horses during 1981 a total number of 144 horses with COPD were examined. Bronchial secretions were taken under endoscopic control and stained with a modified Hansel staining procedure. Whereas 26 horses did not exhibit signs of allergic reactions cytologically and 94 horses showed low amounts of eosinocytes and/or mast cells in their secretion; only the secretions of 24 horses (16,67%) were characterized by fairly high contents of these allergy associated cells and low numbers of neutrophilic ...
Clark ES, Morris DD, Whitlock RH.A 6-month-old Thoroughbred colt was examined because of persistent dysphagia noted since birth. Moderately severe regurgitation occurred when the colt ate semi-solid food or drank. Complete esophageal impaction developed when the colt ate solid material. Endoscopic examination revealed ulceration, dilatation and lack of peristalsis in the area of the previous impaction. Barium esophagram demonstrated the dilatation in the area of the previous impaction. Esophageal manometry revealed prolonged simultaneous contractions throughout the esophagus suggesting the presence of a motor abnormality. The...
Radcliffe RM, Messiaen Y, Irby NL, Divers TJ, Dewey CW, Mitchell KJ, Schnabel LV, Bezuidenhout AJ, Scrivani PV, Ducharme NG.To report a transnasal, endoscopically guided ventral surgical approach for accessing the cranial and caudal segments of the sphenopalatine sinus for mass removal in a horse. Methods: Case report. Methods: Adult horse with acute onset blindness referable to a soft tissue mass within the sphenopalatine sinus. Methods: A 7-year-old Warmblood gelding presented with a history of running into a fence and falling. No neurologic signs were identified at initial examination but acute blindness was noted 3 weeks later. On computed tomography (CT) the sphenopalatine sinus was filled with a large homogen...
Fenger CK, Kohn CW.A 20-month-old Quarter Horse stallion was admitted for evaluation of labored breathing, honking cough, and bilateral epistaxis that were caused by pneumonia and collapsed trachea. A transtracheal aspiration revealed highly cellular, serosanguineous fluid. Radiography revealed a patchy alveolar pattern and a narrowed tracheal lumen. Endoscopy confirmed narrowing of the tracheal lumen. Streptococcus zooepidemicus was isolated on culture of the transtracheal aspirate. The horse responded to penicillin treatment, and the tracheal collapse improved endoscopically after 4 days, with complete recover...
Almonte H, Schumacher J, Johnson CR, Berk JT, Bell RP.To the authors' knowledge, the effect of a combination of butorphanol tartrate and detomidine hydrochloride on the laryngeal function and symmetry of the arytenoid cartilages in young Thoroughbred horses has not been examined. Therefore, this study aimed to examine the effects of administration of butorphanol and detomidine on left-to-right rima glottidis ratio (L:R RGR), cross-sectional area of the rima glottidis (CSARG) and grade of laryngeal function of Thoroughbred yearlings examined endoscopically at rest. Forty-six Thoroughbred yearlings underwent laryngeal video endoscopy, at rest, befo...
Allen KJ, Franklin SH.Overground endoscopy is being performed with increasing frequency in the UK. A previous study has shown that the type of exercise test may affect the diagnosis of upper respiratory tract (URT) obstructions. The successful clinical application of overground endoscopy systems requires understanding of appropriate field exercise testing protocols. Objective: The aim of this study was to report the exercise test parameters used during overground endoscopy in UK Thoroughbred racehorses and to investigate potential effects of these on the diagnosis of URT obstructions. Methods: The exercise test par...
Dotzel AR, Baratt RM.The use of oral endoscopy can be very beneficial in that it helps the clinician to perform a more thorough oral examination. However, due to the high cost, most commercially available equine oral endoscopy systems have been out of reach for clinicians who practice equine dentistry outside a large hospital setting. This article details how to set up an oral endoscopy system that can be used on equine patients either in an ambulatory practice or in a hospital setting. The system is more cost-effective than most other systems currently on the market without sacrificing functionality or image qual...
Bennett DG.Routine examination of the digestive system relevant to purchase includes gross examination of the feces, auscultation of the abdomen, and examination of the oral cavity and teeth for verification of age and identification of any gross abnormality. Further examination is indicated only when there is a history of diseases such as colic, especially colic surgery, or esophageal obstruction. Special procedures that might be indicated, depending upon the history and findings on the routine physical examination, include rectal palpation of the abdominal viscera; endoscopic examination of the esophag...
Lilich JD, Gaughan EM.The diagnostic approach to the exercise intolerant racehorse depends on sound, fundamental steps to allow complete examination of the entire horse in a logical, time-efficient fashion. Availability of referral diagnostic modalities should not overshadow the need for collecting a clinical history or performing a complete physical examination. The diagnostic approach to exercise intolerance can be divided into a few basic steps. The first step, conducted without the horse, is a thorough discussion about the horse with the trainer and/or owner. Many clinical histories are complex and therefore fo...
Tate LP, Newman HC, Cullen JM, Sweeney C.Laryngeal surgery in the equine is customarily and routinely performed by means of a ventral laryngotomy incision. Such procedures are usually performed under deep general anesthesia with the horse in dorsal recumbency. The objective of this work was to determine the efficacy of an endoscopic approach coupled to a Nd:YAG laser fiber in performing arytenoidectomy. Arytenoidectomy is commonly indicated in the treatment of arytenoid chondritis and in the failure of prosthetic implantation for left laryngeal hemiplegia. This preliminary study was undertaken to determine the feasibility of the endo...
Todhunter RJ, Stick JA, Slocombe RF.The effects of 3 feeding techniques on healing of a cervical esophageal mucosal resection and anastomosis were investigated in 16 horses. Horses were fed a moistened pelleted diet 1 of 3 ways: 1) per os (n = 5), 2) by nasogastric (n = 5) or 3) by esophagostomy tube (n = 6) until the 14th postoperative day. The pelleted diet was then fed orally in all horses until euthanasia on the 60th postoperative day. Immediate postoperative feeding per os was unsatisfactory, as only 2 of 5 horses survived in this group. Endoscopic evaluation revealed that mucosal dehiscence of varying degrees occurred, wit...
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...
Katz LM, Ragle CA.Horses with tears that involve all layers of the rectum except the mesocolon (grade IIIb) have a poor prognosis for survival because of the difficulty in treating these wounds and the propensity for them to progress to full perforations (grade IV). Most treatments for grade-IIIb rectal tears involve surgery of some kind, but not all grade-IIIb rectal tears require surgical intervention. We report on 4 horses with grade-IIIb rectal tears that were evaluated via palpation per rectum and endoscopy. Two of 4 horses were admitted with signs consistent with shock and endotoxemia, and evaluation of a...
Inoue Y, Sekiguchi M.Therapeutic techniques for oviductal obstruction in the mare are limited. Nonsurgical and retrograde flushing may be an attractive alternative to current treatment methods for oviductal blockage. Objective: To evaluate hysteroscopic selective hydrotubation as a treatment option for presumptive equine oviductal blockage. Methods: Retrospective case series. Methods: A quantity of 10 mL of saline was flushed through the oviducts in 28 standing sedated mares, which had reproductive histories of unexplained subfertility, by inserting a catheter into the uterotubal junction under endoscopic guidance...
Tulleners EP, Harrison IW, Mann P, Raker CW.Left-sided partial arytenoidectomy was performed in eight horses to evaluate healing. Four horses underwent conventional partial arytenoidectomy with suture apposition of the mucosa. In four horses, most of the arytenoid cartilage, including overlying mucosa, vocal fold, and laryngeal saccule, were excised en bloc without mucosal closure. The horses were monitored clinically by endoscopic examination. One horse from each group was euthanatized at weeks 2, 4, 8, and 16. Complete necropsies with gross and histologic examination of the arytenoidectomy sites were performed. Postoperative complicat...
Lean NE, Sole-Guitart A, Ahern BJ.To investigate the feasibility and describe the clinical experience of performing laryngeal tie-forward (LTF) in standing horses unaffected (experimental) and affected (clinical) by intermittent dorsal displacement of the soft palate (iDDSP). Methods: Experimental study and case series. Methods: Five normal experimental controls and five client owned horses affected by iDDSP. Methods: Standing LTF was performed and evaluated in five experimental horses and five clinical cases diagnosed with iDDSP. Standing LTF was performed under endoscopic guidance with horses sedated and the surgical site de...
Heffron CJ, Baker GJ.Fibreoptic endoscopy was used to study the movements of the larynx and pharynx during nasal occlusion in 10 horses, which showed signs consistent with functional pharyngeal obstruction (FPO) on exercise. Cine-endoscopic films were made on 3 such horses. Consideration of the anatomy of the region indicates that FPO may best be regarded as a subluxation of the nasopharyngeal and larygneal airways and it was found that a constant component of the movements which brought about this subluxation was a marked caudal retraction of the larynx. It is suggested that this caudal retraction of the larynx o...
Ohnesorge B, Deegen E.From 1995 to 1997 11 racehorses, one Hanoverian and one Pony were presented to the clinic with a sudden appearing, very loudly gurgling expiratory respiratory noise. Considering the preliminary report and the clinical and endoscopical findings, as exercise induced dorsal displacement of the soft palate (DDSP) was found to be the cause of the respiratory noise. The 13 horses were treated in general anaesthesia by transendoscopic coagulation of the caudal margin of the soft palate with a Neodym-YAG-Laser. This surgical intervention had to be repeated on four horses with unchanged signs. Eight of...
van den Wollenberg L, Sloet van Oldruitenborgh-Oosterbaan MM.Since it has become possible to make an ante-mortem diagnosis of gastric ulceration in horses by means of endoscopy, interest in the presence and treatment of this syndrome has increased. Several endoscopic surveys have indicated that the frequency of gastric ulceration in Thoroughbreds in training is fairly high. Less is known about other breeds and horses that are kept under different (training) conditions. The equine stomach is covered by two different kinds of mucous membranes: squamous and glandular. These two areas differ from one another in the incidence and aetiology of ulceration and,...
Tetens J, Hubert JD, Eddy AL, Moore RM.A 2-year-old Thoroughbred filly was admitted to the hospital for evaluation of exercise intolerance. Resting videoendoscopic evaluation (i.e., while the horse was standing) of the nasopharynx and trachea revealed right arytenoid paresis and a tracheal defect that was 100 cm distal to the external nares. Surgery, consisting of a right prosthetic laryngoplasty, was performed. However, postoperative videoendoscopic evaluation revealed minimal abduction of the affected arytenoid cartilage. Dynamic videoendoscopic evaluation (i.e., while the horse was exercising) revealed the right arytenoid to be ...
Nadruz V, Beard LA, Delph-Miller KM, Larson RL, Bai J, Chengappa MM.Prevention of spread of Streptococcus equi subspecies equi (S. equi) after an outbreak is best accomplished by endoscopic lavage of the guttural pouch, with samples tested by culture and real time, quantitative polymerase chain reaction (qPCR). Disinfection of endoscopes must eliminate bacteria and DNA to avoid false diagnosis of carrier horses of S. equi. Objective: Compare failure rates of disinfection of endoscopes contaminated with S. equi using 2 disinfectants (accelerated hydrogen peroxide [AHP] or ortho-phthalaldehyde [OPA]). The null hypothesis was that there would be no difference bet...
Newton-Clarke MJ, Divers TJ, Delahunta A, Mohammed HO.A study was conducted over a 12 month period to assess the specificity and sensitivity of the 'slap test', using endoscopic evaluation, in the detection of cervical spinal cord and caudal brainstem lesions in horses. Fifteen ataxic horses were subjected to the 'slap test' and subsequently examined post mortem. Twelve out of the 15 had histopathological lesions consistent with their clinical signs. Thirteen horses with no history of neurological dysfunction and no histopathological evidence of cervical spinal cord or brainstem disease were used as controls. The laryngeal adductory responses exh...
Barakzai SZ, Wells J, Parkin TDH, Cramp P.Unilateral ventriculocordectomy (VeC) is frequently performed, yet objective studies in horses with naturally occurring recurrent laryngeal neuropathy (RLN) are few. Objective: To evaluate respiratory noise and exercising overground endoscopy in horses with grade B and C laryngeal function, before and after unilateral laser VeC. Methods: Prospective study in clinically affected client-owned horses. Methods: Exercising endoscopy was performed and concurrent respiratory noise was recorded. A left-sided laser VeC was performed under standing sedation. Owners were asked to present the horse for re...
Minshall GJ, Wright IM.To describe the presentation, clinical, ultrasonographic and endoscopic features associated with a defect in the tarsal sheath wall, to define the cavity created and to describe a method of treatment. Objective: So called 'false thoroughpins' can be caused by defects in the tarsal sheath wall creating a one way valve effect, removal of which could be therapeutic. Methods: Case records and diagnostic images of horses with synoviocoeles associated with the tarsal sheath were reviewed retrospectively and follow-up information obtained. Results: Synoviocoeles were diagnosed in 15 horses. All were ...
Lean NE, Franklin SH, Ahern BJ.To describe left recurrent laryngeal neurectomy (LRLn) performed under standing sedation and evaluate the effect of LRLn on upper respiratory tract function using a high-speed treadmill test (HST). We hypothesized that (1) unilateral LRLn could be performed in standing horses, resulting in ipsilateral arytenoid cartilage collapse (ACC); and (2) HST after LRLn would be associated with alterations in upper respiratory function consistent with dynamic ACC. Methods: 6 Thoroughbred horses. Methods: The horses were trained and underwent a baseline HST up to 14 m/s at 5% incline until fatigue. Evalua...
Laclaire AL, Manguin E, Tanquerel L.Effects of general anesthesia with controlled ventilation on the respiratory system have had limited evaluation in horses. A prospective observational study was performed with eleven client-owned horses undergoing elective surgery. Physical examination, auscultation with a rebreathing bag, complete blood cell count, lung ultrasound imaging, tracheal endoscopy imaging and transendoscopic tracheal wash were conducted before and 24 hours after anesthesia. Lung ultrasound imaging was also repeated just after recovery. A significant increase in blood neutrophil count between pre- and post-anesthesi...
Jeong S, Franklin SH, Van Eps AW, Lean N, Ahern BJ.Evaluate a prototype dynamic laryngoplasty system (DLPS) in horses; a feasibility study. Methods: 7 healthy Standardbred adult horses. Methods: This was an in vivo experimental study. Horses had a standing surgical procedure to induce complete laryngeal hemiplegia, which was subsequently treated using the dynamic laryngoplasty system (DLPS). Activation of the DLPS was achieved using an injection port exiting through the skin (n = 2) or a subcutaneous injection port (n = 5). For each horse, endoscopic examinations of the upper respiratory tract were performed preoperatively, intraoperatively, a...
Equine asthma (EA) is a respiratory syndrome associated with the increase of different leukocyte populations in the bronchoalveolar lavage fluid (BALF). Its pathogenetic mechanisms remain unclear. This study aimed to evaluate the associations between the mRNA expression of different cytokines in the BALF, different EA subtypes and lung function. Fifteen horses underwent physical examination, airway endoscopy, BALF cytology and lung function testing (8/15). One horse did not have evidence of EA and was used as healthy reference, while the others were classified as affected by neutrophilic or mi...
Baldwin CM, Ireland JL, Barakzai SZ.There is no objective information reporting the effect of unilateral laser ventriculocordectomy (VeC) on arytenoid abduction or stability. Objective: To evaluate arytenoid stability and abduction in horses with severe recurrent laryngeal neuropathy (RLN) before and after unilateral laser VeC. Methods: Prospective cohort. Methods: Eight horses with grade C or D exercising laryngeal function that underwent unilateral laser VeC were included. Exercising endoscopy was performed before and ≥6 weeks after left-sided laser VeC. Arytenoid stability at maximal exercise was calculated by measuring t...
Shawaf T.Exercise-induced pulmonary hemorrhage (EIPH) is one of the most commonly diagnosed disorders in racehorses. Many EIPH risk factors such as breed, age, high or low environmental temperature, and distance of the race have been studied in racehorses. Unassigned: The aim of this study was to study the relationship between EIPH and the presence of jugular vein thrombose in racehorses. Unassigned: Forty-eight thoroughbred racehorses randomly selected from animals with exercise intolerance due to respiratory disorders were enrolled in the present study. Clinical and tracheobronchoscopy examinations w...
