This article briefly reviews the causes of unilateral nasal discharge associated with sinonasal disease in the horse. Whilst, computed tomographic and radiographic imaging are often of great diagnostic value, clinical and nasal endoscopic examinations are the initial steps in investigating these disorders. This article reviews the use of oral examination and nasal endoscopy in the investigation of nasal discharge caused by sinonasal disease.

This report describes the identification of C7-T1 discospondylitis on myelography and confirmed on postmortem computed tomography and necropsy in a 4-year-old Standardbred gelding as the consequence of jugular vein catheterization and secondary septic thrombophlebitis. Staphylococcus aureus was isolated from both sites. Diagnosis was complicated by non-specific signs of pain and the acute presentation of the gelding. Clinical signs included cervical pain, low head carriage, fever, and ataxia. Antimicrobial therapy and multimodal pain management were initiated but were unsuccessful. Spread of infection from septic thrombophlebitis has uncommonly been reported in horses, and this is the first reported case of secondary discospondylitis in this species.

This paper describes the clinical and histopathological features of a 16-year-old Cob mare who sustained a hemorrhagic cerebrovascular accident or stroke. The mare presented with an acute onset of neurological signs, with a neuroanatomical localization to the midbrain and thalamus regions. The mare was reported to have suffered from ataxia on all 4 limbs which started 7 days prior to referral, she was also showing several signs of left-sided cranial nerves deficits. On initial examination, the mare presented with quadrilateral ataxia, left-sided facial paralysis, weak tongue tone and a left-sided nose tilt as well as a hemineglect syndrome characterized by an inability to eat food presented on the right side of her mouth. Complete blood count and biochemistry analyses did not reveal any abnormalities, and a standing head CT revealed the presence of a hyperdense lesion localized in the left ventral cortex and thalamus region, which could be consistent with a vascular lesion, cholesterol granuloma or a mass. The mare was monitored, and as her condition slightly improved, she was discharged from the Hospital. Four weeks later, the clinical signs recurred and as the ataxia presented a danger for the mare and anyone handling her, the decision was made to euthanize her. A post-mortem CT scan of the head revealed an enlargement of the previous lesion, and the histopathological examination confirmed the presence of a hemorrhage within the brain, associated with neoplastic emboli. Hemorrhagic stroke has not previously been well described in horses therefore presents a challenge in diagnosis. Treatment in small animals is mainly conservative.

Background: The paracondylar process is of clinical interest due to its proximity to anatomical structures involved in vital functions. There are limited reports describing abnormalities affecting the paracondylar process (PCP), with traumatic fractures being the most prevalent pathology. Affected horses can present with a variety of signs including headshaking, facial paralysis and/or poor performance. In almost all cases reported in the literature to date, computed tomography has been used to diagnose a PCP fracture. Objectives: The aim of this study was to develop a radiographic technique for imaging the PCP, to determine the optimum radiographic projection angle and trial its use in standing sedated horses. Study design: Pilot study conducted in 10 standing sedated horses. Methods: Three tangential radiographs of the left and right paracondylar processes at 5º, 15º and 20º to the transverse plane were obtained in 10 standing sedated horses. Three blinded observers independently ranked each of the three images for clarity of viewing the PCP. The radiographic projection allowed imaging of the ventral portion of the PCP while avoiding superimposition of other osseous structures. Results: The highest grades were obtained for radiographs with a 5º angle from the transverse plane, and the lowest grades were obtained for a 20º angle. Main limitations: Complex anatomy of the PCP with superimposition of osseous and soft tissue structures. Conclusions: The radiographic technique for the PCP can be safely performed in standing, sedated horses. It is suitable for implementation in general veterinary practice before considering referral for advanced imaging techniques in horses presenting with headshaking or facial paralysis.

Lameness in the horse is one of the most common reasons a horse is seen by a veterinarian. As the foot is frequently the source of lameness, research utilizing reversible methods of foot lameness induction are vital to improvements of the knowledge in this area. This literature review aims to describe published methods of reversible foot lameness induction, identify any limitations of these methods, and summarize findings of research where these methods have been utilized.

A fifteen-year-old warmblood gelding was presented with recurrence of a histologically confirmed osteosarcoma of the left second and third metacarpal bones three years after initial diagnosis and treatment. Initially, surgical excision was performed, followed by local injection of carboplatin 11 weeks later. The horse was sound after surgery and was used for low level dressage and jumping. Three years later, the horse developed acute onset of lameness in the left forelimb and a painful soft tissue swelling at the proximomedial metacarpal region. Radiographs showed a spiculated periosteal reaction on the medial aspect of the third metacarpal bone, indicating re-activation of the lesion. Stereotactic radiation therapy was performed with a protocol consisting of three fractions under general anaesthesia (Mo-We-Fr schedule), and a total dose of 30 Gy. The technique used was volumetric modulated arc therapy guided by cone beam computed tomography for daily positioning. Following the radiation therapy, the horse became sound at walk and one month later, it became sound at trot. Follow-up by veterinary examination eighteen months after final treatment revealed no lameness at walk and trot, and a stable radiographic appearance.

** Other clinical commentaries don’t have an abstract, so I have assumed one is not expected?

Background Laser excision is used routinely in the treatment of sarcoids but may be ineffective in cases where complete excision cannot be achieved. A multimodal approach is warranted in these cases. 5-FU may improve the lethal effect of cryotherapy as an adjunct to laser excision. Objectives To compare two treatment protocols for equine sarcoids: laser excision alone versus a combination protocol of laser excision, cryotherapy, and 5-FU chemotherapy. Factors associated with sarcoid recurrence are also investigated. Study Design Retrospective case controlled study. Results Eighty-four horses with 168 histologically confirmed sarcoids were included, with a median follow up time of 39 months (IQR 21-62 months). Sarcoid recurrence at the treated site was reported in 38% of cases and in 23% of any individual sarcoids. No significant difference was demonstrated between treatment categories in either rate of sarcoid recurrence (p=0.45 for any treated horse, p=0.63 for individual sarcoids) or time to sarcoid recurrence (p=0.73). Sarcoid recurrence was higher in horses with a greater number of sarcoids (OR 1.2 (1.0-1.5), p=0.03); when treatment had been received prior to admission (OR 7.6 (2.0-33), p=0.004); for individual sarcoids ≥100mm in diameter (OR 5.6 (1.1-30), p=0.03); and for treatment under general anaesthesia (OR 5.0 (1.4-19), p=0.01). Horses with urogenital sarcoids and >1 mixed sarcoid experienced more rapid recurrence (HR 3.6 (1.3-10), p=0.02 and HR 9.9 (3.3-30), p<0.001) and recurrence was less rapid following the treatment of a horse’s first sarcoid (HR 0.3 (0.1-0.7), p=0.009). Main Limitations Significant differences in case populations in each treatment category. Treatment selection was neither blinded nor randomised and missing data and recall bias limit the study’s power. Sarcoid recurrence was owner reported. Conclusions When assessing the likelihood of sarcoid recurrence, characteristics of the individual patient and sarcoid(s) are likely to be more significant than selection of any individual treatment protocol.

A 15-year-old Warmblood gelding was presented with macroscopic hematuria and stranguria symptoms for two months. Cystoscopy revealed a pedunculated cauliflower-like mass, flowing from the right ureteral orifice into the bladder. Ureteroscopy showed a right dilated ureter (2.3 mm). The ureteral lumen mucosa was smooth and the mass had its origin approximately 10 cm cranial from the orifice. The right kidney was macroscopically on ultrasound within normal range. The mass was removed transendoscopically by means of a cautery snare leaving a small part at the base. Histopathological analysis identified it as a mucosal polyp. Recovery was uncomplicated and the gelding was discharged three days after surgery. A follow up 5 months later showed no signs of inflammation and the remaining small stalk in the right ureter.

Perineural anaesthesia is a useful technique in equine surgery, providing pre-emptive targeted anaesthesia of the surgical site, reducing volatile anaesthetic requirements, improving recovery quality and providing post-operative pain relief. Surgery under standing sedation in horses has increased in popularity, mandating the need for effective locoregional anaesthesia and analgesic techniques. Nerve location techniques offer greater accuracy than blind techniques when placing injectate. These methods can help to avoid structures such as blood vessels and minimise direct nerve damage during needle placement, reducing the chance of procedure-related complications. This review will discuss the most pertinent research in the veterinary literature where objective methods of nerve location have been used to perform peripheral nerve blocks in horses. The efficacy of using objective methods to perform nerve blocks in equine anaesthesia is discussed by the authors, providing useful information to equine anaesthetists, and potentially improve the quality of anaesthesia and analgesia in horses.

EVE Clinical CommentaryThe case report by describes an interesting case of rib fracture in a race horse with an attributable hindlimb lameness. This case is the first to suggest that caudal rib fractures are a cause of hindlimb lameness and peri regional diagnostic analgesia of a rib fracture can be used to alleviate hindlimb lameness.A recent retrospective study reported 73 horses diagnosed with a rib fracture of which 56% (41/73) presented due to poor performance with a fewer number of horses presenting with lameness as a primary complaint (21/73). Undoubtedly rib fractures are painful in the acute stages of injury, with the most common site for rib fracture in a horse being dorsally (5-15cm from the costovertebral junction) on the 18th rib (Hall et. al. 2022). In this study, not all horses with caudal rib fractures were found to have lameness those that were lame had a variable pattern of lameness. All of the horses which underwent diagnostic analgesia were found to have lameness independent to the rib fracture. However only a small percentage of horses underwent diagnostic analgesia, a limitation of a retrospective study.An alternative retrospective case series of 50 rib fractures reported 5 fractures of the first rib which all occurred in racing thoroughbreds (age 2-7 years with a median age of 3), all of which had ipsilateral forelimb lameness. In the absence of a traumatic incident the authors suggested that fractures of the 1st rib may represent fatigue fracture pathology associated with training. A similar aetiology is possible for caudal rib fractures but is considered unlikely as this injury is not over represented in racing Thoroughbreds compared with a general population of horses and trauma remains the most likely cause.Ribs can be imaged in detail with nuclear scintigraphy given the relatively small amount of overlying soft tissue. Orthogonal images (lateral, dorsal and oblique) should be used to localise region, extent, pattern and origin of increased radiopharmaceutical uptake. Nuclear scintigraphy is highly sensitive in identifying osteoblastic activity but has low specificity for identifying the nature of the pathological process. Fractures show increased radiopharmaceutical uptake within 24-72 hours post injury, making nuclear scintigraphy highly sensitive in the acute stage of disease verses radiographic signs which may not be seen for around 7-10 days unless the fracture is displaced. The appearance of a fracture on nuclear scintigraphy includes 5-7 days of diffuse intense uptake, 1-4 weeks of focal intense uptake (figure 1.) and then a gradual decrease of radiopharmaceutical uptake over the next 6-12 months. This prolonged visibility on scintigraphy means that is difficult to age a fracture based on scintigraphy alone. Ultrasonography is potentially more suitable to monitor fracture healing and identify those cases which are non-healing and requiring intervention. Costochondral junctions normally have a moderate increased radiopharmaceutical uptake on nuclear scintigraphy and should not be mistaken for a rib fracture (figure 1.). The caudal ribs overly the kidney (figure 1.) but in most instances have a mild to moderate diffuse region of increased radiopharmaceutical uptake. The use of furosemide one hour before imaging has been advocated to improve soft tissue clearance and improve image count to background ratio. This was evaluated in a recent study where 1mg/kg furosemides was administered intravenously 1 h post 99m Tc-HDP administration and the image quality was assessed subjectively and semi-quantitively. There was no significant difference in image quality or radiation dose rate to handler, with a minimum distance of 30cm distance having the most effect on reducing handler dose rate by 65% .Ultrasonographic examination is highly sensitive and specific in identifying rib fractures (Hall et. al. 2022). If a rib fracture is suspected in the initial stages of examination, then survey ultrasonographic examination of the ribs is recommended, especially the caudal ribs. However, rib fractures rarely result in focal localising pain on palpation and so even a detailed clinical examination may be unrewarding. Ultrasonography of the ribs is a simple technique; clipping isn’t required and discontinuity and callus within the lateral cortex of the ribs is easy to identify (Figure 2) but should not be confused with the costochondral junction (figures 3 and 4). The costochondral junction is identified by the presence of hypoechoic cartilage and it should be noted that the margins of adjacent ribs are normally irregular at this site. In contrast, a rib fracture does not contain hypoechoic cartilage, though the rib margins are likely to be irregular and commonly periosteal new bone may be seen.In this case of hindlimb lameness due to fracture of the 18th rib , the horse took 12 months to recover and resume ridden exercise with conservative therapy. Ultrasonographic examination can monitor fracture healing and is useful in identifying non-healing fractures which may represent surgical candidates. Hall and colleagues (2022) reported six horses which underwent surgery due to failed initial conservative management which resulted in continued fracture instability, callus at the fracture site or fracture displacement causing impingement on adjacent ribs. One horse which underwent wedge ostectomy and internal fixation with a locking compression plate returned to its previous level of exercise. All other surgically managed cases (5/73) underwent partial rib resection. Most horses in this study were managed conservatively (67/73). Given the very small number of surgically managed cases it is not possible to determine if fracture healing or outcome would have been improved if surgical intervention had been performed in more cases.Peri-regional analgesia of a rib fracture is commonly used in human medicine as a therapeutic aid and is easy to perform in the horse. In this instance the ipsilateral hindlimb lameness was partially alleviated by this technique in the acute stage of lameness and completely abolished in the chronic stage of lameness. Perineural analgesia can result in increased radiopharmaceutical uptake within the soft tissues on bone phase scintigraphy, up to 7 days post blocking , with 50% of horses having uptake at the site of a tibial perineural injection one day post injection, 25% of horses at the block site 3 days post injection and 1 horse with increased radiopharmaceutical uptake 7 days post injection. An appropriate washout period is recommended prior to scintigraphy if perineural analgesia has been performed to prevent false positive results.Although rib fractures are largely under reported in adult horses this case report and recent retrospective studies confirm they should be considered a differential diagnosis for cases of poor performance and both fore and hind limb lameness. Diagnostic analgesia could be used to determine significance of the rib fracture in cases of hind limb lameness.

Background: Ocular diseases, especially corneal diseases, are common in horses and their occurrence is associated with trauma. It is not known if management practices promote or prevent the development of ocular diseases, such as corneal ulcers. Objectives: This study aimed to evaluate how stable management practices, such as environment, feeding, or use of fly masks, are related to the development of eye diseases, primarily corneal ulceration, in horses. Study design: A survey of horse owners in the state of North Carolina was conducted which asked owners how they managed their horses and their responses were correlated to the types of eye diseases the horses experienced. Methods: Data collected from the survey included the primary environment of the horse (stable or pasture), type and method of feeding of hay, use of fly masks, and eye diseases that the horses have developed. Correlations between management practices and eye disease were then performed. Results: Of 446 horses, 161 (36% of total) had been diagnosed with a corneal ulcer, 44 (10%) had multiple corneal ulcers, 65 [15%] horses had uveitis, and 15 (3%) had immune-mediated keratitis. Horses that were kept in pasture exclusively were significantly less likely to have had a corneal ulcer than horses kept in a combination of pasture and stalls (p=0.0348). There were no significant correlations between types of hay or how hay was fed with the occurrence of corneal ulceration or other ocular diseases. Main limitations: Results, such as disease diagnoses, are solely based on horse owner responses and not medical professionals. Conclusions: Horses kept primarily in pasture have fewer ocular diseases, likely because they sustain less ocular trauma compared to horses kept in stables. How hay is fed does not correlate with the incidence of corneal or other ocular disease.

A six-week-old male Shetland pony is presented with pollakiuria and a scrotal mass. The diagnostic procedures conducted included a thorough clinical examination, external palpation, a scrotal ultrasonographic exam and urinary catheterization. These revealed an indirect herniation of the urinary bladder into the tunica vaginalis. Subsequently, the case was managed surgically by performing a partial cystectomy through an inguinal approach. Bilateral castration was performed with the affected side an additional closure of the superficial inguinal ring. Five months post-surgery, a routine telephone questionnaire highlighted no post-operative concerns. Gross examination of the inguinal region revealed no abnormalities and the foal was maturing as expected.

Difficulty to extubate any patient is not a problem commonly thought of during general anaesthesia. This case report describes some of the factors that lead to this predicament and the successful surgical removal of the endotracheal tube via a tracheostomy. This case report also highlights some of the deficiencies in the clinical practice of veterinary anaesthesia. Further research is required for the selection size criteria of endotracheal tubes in all species and the monitoring of cuff pressures during general anaesthesia.

The use of intracytoplasmic sperm injection (ICSI) for the production of equine embryos has significantly increased over the past decade, leading to the creation of labs specific for ICSI and related in vitro fertilization techniques. However, the commitment, resources and skills necessary for developing a viable IVF lab can be underestimated or under-appreciated. The purpose of this paper is to share the difficulties our clinic encountered when developing an IVF lab.

Simple dilution of semen is the oldest method to process semen for artificial insemination with either fresh or cooled. This was developed prior to the optimization centrifugation techniques for semen through a combination of trial and error and research. Simple dilution and is a faster method to process semen, is easy to use and works in many circumstances. For on farm semen use a 1:1 (v/v) semen to extender ratio is used. A variety of other techniques have been developed, such as cushion centrifugation, density gradient centrifugation and sperm filtration. Cushion centrifugation is used to concentrate the sperm and allows higher centrifugation speeds than centrifugation alone. This allows for improved recovery rates of sperm. Density gradient centrifugation has been used to select for morphologically normal sperm but suffers from low recovery rates. Processing sperm with this technique can result in improved motility and improved DNA integrity of sperm. Sperm filtration is another method to concentrate sperm without the use of centrifugation; however, this technique has lower recovery rates compared to cushion centrifugation. This review will discuss these techniques in the application of processing equine semen for either fresh or cooled-shipped use.

Enteroliths, faecaliths, ingested foreign bodies, and bezoars are examples of focal intraluminal obstructions that can lodge in inaccessible parts of the gastrointestinal tract. Pneumatic lithotripsy, as described in the accompanying article, is an option to manage obstructions caused by mineralized concretions. However, pneumatic lithotripsy may not be safe or effective for all intraluminal obstructions. Awareness of other strategies or secondary abdominal approaches to address these challenging presentations can help improve the surgeon's ability to problem solve in these situations and achieve successful resolution of the obstruction.

Recognition of the role that biofilms play in the persistence of chronic wounds and lack of response to therapy in horses is increasing. Prevention of biofilm development in early stages of wound care involves three primary strategies: wound debridement and cleansing to reduce bacterial counts in the wound bed, appropriate use of advanced wound dressings, and implementation of topical antimicrobial agents. Once formed, eradication of biofilms requires elimination to improve the wound environment for contraction and epithelialization while not further harming the native cells integral to the healing process, which is achieved predominantly through repeated lavage and debridement combined with topical antimicrobial therapy. This review will establish why and how biofilms form, how to recognize clinical indications that biofilms have formed in equine wounds, and to review current diagnostic options and biofilm-based wound care (BBWC) strategies to eradicate biofilms. Clinical scenarios for cases in which biofilms developed and were successfully treated will be presented. This review will advance practitioners’ understanding of the presence and role of biofilms in chronic wounds and provide an updated summary of recommended treatment strategies.