Restoration of function following traumatic superior eyelid avulsion in a horse treated with advancement flap blepharoplasty (H-plasty) and subdermal hyaluronic acid filler.

OBJECTIVE: To describe the successful restoration of superior eyelid function in a horse following traumatic avulsion using an advancement flap blepharoplasty and subdermal hyaluronic acid filler. ANIMAL STUDIED: A 21-year-old American Paint Horse stallion who was attacked by a fellow stallion resulting in numerous traumatic injuries including avulsion of approximately 75% of the left superior eyelid. PROCEDURES: With standing sedation and locoregional anesthesia, the superior eyelid wound was debrided and an advancement flap blepharoplasty (H-plasty) and temporary tarsorrhaphy were performed. Routine healing of the surgical site occurred over the subsequent weeks, though lagophthalmos persisted. At 2 and 4 weeks post-operatively, 2.4% cross-linked hyaluronic acid was injected subdermally into the superior eyelid to attempt to improve corneal coverage. At 8 weeks post-operatively, a complete blink was restored and the cosmetic outcome was good. CONCLUSIONS: Injection of subdermal hyaluronic acid filler following eyelid injuries or blepharoplastic procedures that result in lagophthalmos can improve corneal coverage by the eyelids and allow for maintenance of a comfortable and visual eye.

Endoscope-assisted three-wire technique for extensive nasal septum resection in horses.

OBJECTIVE: To describe a 3-wire method with endoscopic guidance for extensive nasal septum resection. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: Thirteen horses with nasal septum diseases. METHODS: In anesthetized horses in left lateral recumbency, endoscopic guidance was used to place obstetrical wires for the ventral and caudal incisions in the nasal septum and a trephine opening was used to place the dorsal wire. The rostral aspect of the septum was incised with a scalpel, followed by incisions with the preplaced wires, and the nasal passages were packed with gauze. Horses were recovered with a temporary tracheotomy. RESULTS: Conversion to intraoral placement of wires was required in two horses, one to correct entangled wires and the other because hemorrhage obscured the endoscopic view. Exercise tolerance was improved postoperatively, abnormal respiratory noise was decreased or eliminated by surgery in all horses, and all owners were satisfied. One Thoroughbred racehorse performed with modest success. CONCLUSIONS: Modification of the 3-wire method was effective and safe for extensive nasal septum removal. Technical complications of the procedure include entangling of wires and intraoperative hemorrhage. CLINICAL SIGNIFICANCE: Endoscopic guidance can be used to place obstetrical wires for nasal septum resection in small horses and precludes use of a large tracheotomy for anesthetic delivery. Reasons for athletic failures were difficult to establish retrospectively, although assessment of postoperative noise at speed might be more relevant to recovery of athletic potential than assessment at slower gaits.

Clinical findings, surgical techniques, prognostic factors for short-term survival and long-term outcome in horses with acquired inguinal hernias: Ninety-eight cases (2005-2020).

OBJECTIVE: To report findings, outcome and determine variables associated with survival in horses with acquired inguinal hernia (AIH). STUDY DESIGN: Retrospective study. ANIMALS: A total of 98 cases in 97 horses. METHODS: The medical records (2005-2020) of horses diagnosed with AIH were reviewed. Retrieved data included signalment, history, clinical variables, surgical aspects, postoperative complications, and short- and long-term outcomes. Logistic regression analyses were used to determine factors associated with short-term survival (p < .05). RESULTS: Manual reduction was attempted in a third of the cases (32/98, 33%) and emergency surgery to reduce the hernia was performed in 64 of 98 (65%) cases. Concurrent small intestinal (SI) volvulus was identified in 26 (26/98, 27%) cases. Castration was the most common technique used to prevent recurrence (64/94, 68%). Overall AIH recurrence rate was 11% (11/98). A total of 59 (59/98, 60%) cases survived to hospital discharge and 49 of 52 (94%) cases were still alive after 12 months. Cases admitted within 10 h of colic signs had increased odds of survival (72%) compared to those admitted after 10 h (26%; p < .001). Draft breeds (p = .021), high heart rate on admission (p = .001) and concurrent SI volvulus (p = .048) were associated with reduced survival to hospital discharge. CONCLUSIONS: Horses with AIH had a higher risk of concurrent SI volvulus and lower survival than reported. Draft breeds, high heart rate on admission and concurrent SI volvulus were associated with reduced short-term survival. CLINICAL SIGNIFICANCE: The results of this study should help in prognostication for horses with AIH.

The influence of a tension band fixation as an adjunct for arthrodesis of the metacarpophalangeal joint in the horse.

OBJECTIVES: To determine the influence of a stainless-steel cable (SSC) tension band fixation as an adjunct to a locking compression plate (LCP) for arthrodesis of the equine metacarpophalangeal (MCP) joint. STUDY DESIGN: Experimental. An ex vivo biomechanical paired equine cadaver limb study. SAMPLE POPULATION: Five MCP joint pairs were collected from adult Thoroughbred horses, euthanized for reasons unrelated to orthopedic disease. METHODS: Each pair of MCP joints were randomly implanted with either a dorsally placed 5.5 mm LCP and a palmarly placed 2.0 mm SSC or a dorsally placed 5.5 mm LCP alone. Each construct was tested in cyclic loading followed by single cycle to failure in axial compression. Displacement at a target load of 1 kN over 3600 cycles at 1 Hz was recorded prior to single cycle to failure testing. RESULTS: In cyclic testing, displacement was not significantly different between the first and last 5% of testing cycles regardless of construct. Maximum displacement of each construct during cyclic testing was <1.1 mm. In single cycle testing, the observed yield point did not reveal any difference between LCP and LCP-SSC (p = .440). The maximum load at failure was significantly higher in LCP-SSC compared to constructs with the LCP alone (p = .046). CONCLUSION: The addition of the SSC to the LCP did not statistically affect construct displacement during cyclic loading or construct yield load during subsequent single cycle to failure. CLINICAL SIGNIFICANCE: This study provided much needed information regarding the necessity of a tension band SSC application in the arthrodesis of the MCP/MTP joint in horses.

Ex-vivo evaluation of a percutaneous looped thread desmotomy of the accessory ligament of the deep digital flexor tendon in horses.

OBJECTIVE: To determine the ability to completely transect the equine accessory ligament of the deep digital flexor tendon (AL-DDFT) via an ultrasonographically-guided, percutaneous looped thread desmotomy using FiberWire suture as a cutting device. STUDY DESIGN: Ex-vivo study. SAMPLE POPULATION: A total of 24 normal equine distal forelimb specimens. METHODS: Under ultrasonographic guidance, a Jamshidi needle was placed between the suspensory ligament and the AL-DDFT, and between the AL-DDFT and the deep digital flexor tendon, through two stab incisions. FiberWire suture was fed through the needle and looped around the AL-DDFT. Using a sawing motion, the ligament was transected, and the suture exited through the lateral incision. Surgical sites were dissected and assessed for completeness of transection, iatrogenic injuries, and suture remnants. Descriptive statistics were reported. RESULTS: The procedure met the successful criteria in 18/24 (75%) of the limbs. The median surgical time was 11 min (range 7-25). No suture failure or suture remnants were noted in any of the specimens. Complications included iatrogenic injury to the medial and lateral neurovascular bundles in 4/24 and 1/24 specimens, respectively. CONCLUSION: Complete transection of the AL-DDFT was achieved in 22/24 (92%) of the specimens; however, the neurovascular bundles were injured in 5/24 (21%) of the specimens. CLINICAL SIGNIFICANCE: A percutaneous looped thread desmotomy of the AL-DDFT can be studied as an alternative technique for use in equine models prior to its clinical use in patients. Additional studies are required to evaluate efficacy and safety in anesthetized or standing horses.

Laparoscopic cryptorchidectomy using a resorbable self-locking loop device in dorsally recumbent horses.

OBJECTIVE: To report the use and feasibility of a self-locking resorbable loop device for cryptorchidectomy. STUDY DESIGN: Clinical prospective study. POPULATION: Twenty horses. METHODS: Horses suspected to have an abdominal testicle/s after admission work-up were enrolled. Horses were anesthetized in dorsal recumbency and a standard laparoscopic technique was performed. The looped device was inserted into the abdomen, glided around the testis/cord and tightened. Then, the spermatic cord was transected prior testis removal. Surgical procedure details and remarks, perioperative complications and total surgical time were recorded. Short- (>3 weeks) and long-term (>6 months) follow-ups were obtained by telephone questionnaire. RESULTS: Median total surgical time was 67 min (range: 43-189 min) and significantly shortened after the first four horses. The loop device was easily glided around 13/20 abdominal testes and required more time and technical skills around larger testes (≥3 years). Excellent intraoperative hemostasis was achieved in 17 horses. Three horses demonstrated mild intraoperative bleeding that required retightening, device replacement or adding a second device, respectively. Three horses developed mild postoperative hemoabdomen identified ultrasonographically and were successfully managed medically. Follow-up revealed no significant complications related to the procedure. One horse was euthanized for colic 4 months after surgery and one died of hemolytic shock 17 months postoperatively. CONCLUSION: This device represents another method to perform equine cryptorchidectomy that requires minimal training and laparoscopic expertise but demands knowledge of the device and application to prevent complications. CLINICAL SIGNIFICANCE: Laparoscopic cryptorchidectomy using this device is an alternative technique for horses <3 years.

Comparison of equine paranasal sinus trephination complications and outcome following standing computed tomography, radiography and sinoscopy guided approaches for the treatment of sinusitis.

OBJECTIVE: The recent availability of standing computed tomography (CT) for equine paranasal sinus disease has enhanced diagnosis and enabled more targeted surgery compared to radiography and sinoscopy. To date, there have been no studies which have critically evaluated the benefit of preoperative CT versus radiography and sinoscopy on complications and outcome in horses undergoing sinus trephination. STUDY DESIGN: Retrospective study. ANIMALS: A total of 229 equids. METHODS: The medical records of equids (229) presented for sinusitis treated via trephination that had CT, radiography and/or sinoscopy at time of surgery between 2009 and 2022 were reviewed. Outcome and complications were evaluated for six different pre- and intraoperative imaging modalities. RESULTS: The six groups did not differ in demographics or disease category, though equids with less weight (p = .0179) and shorter disease duration (p = .0075) were more likely to have radiography and sinoscopy based surgical planning. Short-term postoperative complications occurred in 30.1% and were higher in groups using preoperative CT imaging (p = .01), with hemorrhage being the most common surgical complication. Following initial trephination surgery, 57.0% (127/223) of cases resolved and there was no difference between the imaging groups. Final resolution after follow-up medical or surgical treatment increased to 94.6% (211/223) and was not different between the imaging groups or between primary or secondary sinusitis. Additional nasal fenestrations to improve sinonasal drainage, maxillary septal bulla fenestrations and trephinations to treat nasal conchal bullae were made in the CT groups. CLINICAL SIGNIFICANCE: CT provided additional diagnostic information and enabled different surgical approaches but did not improve resolution in this study population.

Arthroscopically guided lag screw fixation of subchondral bone cysts in the medial femoral condyle in Thoroughbred racehorses: description of technique and comparative results.

OBJECTIVE: To describe an arthroscopically guided technique for lag screw placement across subchondral bone cyst (SBC) in the medial femoral condyle (MFC) and to compare postoperative racing performance with corticosteroid injection and cyst debridement. STUDY DESIGN: Retrospective cohort study. ANIMALS: One hundred twenty-three horses with 134 MFC SBCs undergoing treatment at a single referral hospital in the UK between January, 2009, and December, 2020. METHODS: Sex, age, limb affected, radiographic cyst dimensions, preoperative and postoperative lameness, surgical technique (lag screw placement, cyst debridement, intralesional corticosteroid injection), and, where applicable, screw positioning were recorded retrospectively. A ratio was calculated using measurements from preoperative and postoperative radiographs. Outcome was assessed by resolution or improvement in lameness, reduction in cyst size, and starting one race after treatment. Outcome data was compared between treatment groups. RESULTS: Twenty-six of 45 (57.8%) horses that underwent transcondylar screw placement raced postoperatively, at a median of 403 days between surgery and first postoperative race. There was no difference between treatment groups with regard to racing or preoperative and postoperative lameness. Cysts treated with transcondylar screw placement had a greater reduction in cyst size and a reduced period of convalescence in comparison with those that underwent debridement; the results were similar to those treated by intralesional corticosteroid injection. CONCLUSION: Postoperative racing rates were similar for all techniques. Convalescence was reduced for lag screw placement and corticosteroid injection compared to debridement. CLINICAL SIGNIFICANCE: The arthroscopically guided technique results in radiographically consistent screw placement and cyst engagement and offers a viable alternative to other treatments.

Outcome of tenoscopically guided palmar/plantar annular ligament desmotomy for the treatment of palmar/plantar annular ligament constriction without concurrent intrathecal soft-tissue injury in a UK horse population.

OBJECTIVE: To determine the outcome of tenoscopically guided palmar/plantar annular ligament (PAL) desmotomy to treat PAL constriction without concurrent intrathecal soft-tissue injury, notably of the digital flexor tendons and manica flexoria. STUDY DESIGN: Retrospective multicenter cohort study. ANIMALS: Sixty-five horses. METHODS: Horses from four UK equine hospitals, with digital flexor tendon sheath (DFTS) tenosynovitis, which underwent tenoscopically guided PAL desmotomy for treatment of PAL constriction between 2017 and 2022 were included. All horses had lameness isolated to the DFTS/PAL, and PAL constriction was diagnosed tenoscopically when there was difficulty maneuvering the endoscope into or through the fetlock canal. Horses with tearing of the digital flexor tendons and/or manica flexoria, or any other intrathecal pathology, were excluded. Follow up was via structured telephone questionnaire. RESULTS: Follow up (median 25 months) was available for 61 horses with cobs and ponies predominating. Forty-two returned to their previous level of work, or a higher level, postoperatively and 50 owners were satisfied with the outcome of surgery. Eleven horses returned to lower level exercise, and six were retired/euthanized as they did not regain soundness. Fifty-two horses achieved soundness (median 3 months postoperatively). CONCLUSION: Tenoscopically guided PAL desmotomy for the treatment of PAL constriction in the absence of intrathecal soft tissue injury had a good prognosis for return to previous levels of exercise in a UK horse population. CLINICAL SIGNIFICANCE: The prognosis for horses undergoing tenoscopically guided PAL desmotomy to treat PAL constriction in the absence of intrathecal injury is better than previously described. Cobs and ponies seem to be predisposed to PAL constriction in agreement with the previous literature.

Equine subchondral lucencies: Knowledge from the medial femoral condyle.

Equine subchondral lucencies (SCL) have been described since the first availability of suitable radiographic equipment. The initial clinical sign can be lameness, but SCLs are often first found on surveys of juvenile horses and are primarily a radiographic concern for public auctions. When lameness is present, it varies from subtle to obvious and can be intermittent. Some SCLs heal spontaneously, and some remain blemishes, but when the SCL and lameness are persistent, further damage to the joint and limitations to an athletic career are likely. SCLs were initially described in the distal limb followed by the stifle, and the medial femoral condyle (MFC) is now considered the most common location. The aim of this review is to highlight the initial pathology and discuss the clinical and experimental information available on equine SCLs. SCL treatment has evolved from rest alone and has progressed to debridement, grafting, intralesional injection, and most recently, transcondylar screw and absorbable implant placement. Comparison of success rates between techniques is difficult due to variations in follow-up and outcome measures, and no single technique is best for all SCLs. Treatment appears to increase success by 15%-20% over rest alone, but the method chosen depends on many factors. This review emphasizes the need for further work to fully understand SCL formation and all aspects of trabecular bone healing to optimize surgical therapy and improve treatment success.

Dorsal-to-palmar branch neuroanastomosis in horses undergoing palmar digital neurectomy does not reduce neuroma formation or improve outcome.

OBJECTIVE: Chronic foot pain, a common cause of forelimb lameness, can be treated by palmar digital neurectomy (PDN). Complications include neuroma formation and lameness recurrence. In humans, neuroanastomoses are performed to prevent neuroma formation. The aim of the study was to evaluate the outcome of horses undergoing dorsal-to-palmar branch neuroanastomosis following PDN. STUDY DESIGN: Retrospective case series. ANIMALS: Eighty-five horses with PDN and dorsal-to-palmar branch neuroanastomosis. METHODS: Medical records for horses undergoing this procedure at two hospitals between 2015 and 2020 were reviewed. Palmar and dorsal nerve branches of the PDN were transected and end-to-end neuroanastomosis was performed by apposition of the perineurium. Follow-up was obtained from medical records and telephone interviews. Success was defined as resolution of lameness for at least one year. RESULTS: Lameness resolved following surgery in 81/85 (95%) horses with 57/84 (68%) sound at one year. Postoperative complications occurred in 19/85 (22%) cases. The main limitations of the study were an incomplete data set, inaccurate owner recall, and variations in procedure. CONCLUSION: Compared to previous studies, this technique resulted in similar numbers of horses sound immediately after surgery, a comparable rate of postoperative neuroma formation but a higher recurrence of lameness rate at 1 year postoperatively. CLINICAL SIGNIFICANCE: End-to-end neuroanastomosis of the dorsal and palmar branches of the PDN does not reduce the rate of neuroma formation in horses. Long-term outcome was less favorable compared to previously reported PDN techniques.

Positron emission tomography assessment of metacarpal/metatarsal condylar fractures post surgical repair: Prospective study in 14 racehorses.

OBJECTIVES: To assess 18F-sodium fluoride (18F-NaF) positron emission tomography (PET) findings associated with metacarpal/metatarsal condylar fractures at the time of fracture repair and through healing. STUDY DESIGN: Prospective descriptive study. ANIMALS: Fourteen Thoroughbred racehorses. METHODS: 18F-NaF PET was performed within 4 days of surgical metacarpal/metatarsal condylar fracture repair, on both the injured and contralateral limb. Follow-up PET scans were offered at 3- and 5-months post fracture repair. Areas of abnormal uptake were assessed using a previously validated grading system. RESULTS: Eight fractures were located in the parasagittal groove (PSG) (six lateral and two medial) and six fractures were located abaxial to the PSG (non-PSG) through the palmar/plantar condyle (all lateral). All horses in the latter group had uptake in the lateral palmar condyle of the contralateral limb suggestive of stress remodeling. Three horses with PSG fractures had uptake in a similar location in the contralateral limb. Horses with lateral condylar fracture only presented minimal or mild uptake in the medial condyle, which is considered atypical in the front limbs for horses in full training. Four horses developed periarticular uptake in the postoperative period suggestive of degenerative joint disease, three of these horses had persistent uptake at the fracture site. These four horses did not return to racing successfully. CONCLUSION: The findings of this study provide evidence of pre-existing lesions and specific uptake patterns in racehorses suffering from metacarpal/metatarsal condylar fractures. CLINICAL SIGNIFICANCE: PET has a possible role in the prevention, diagnosis, and postoperative monitoring of metacarpal/metatarsal condylar fractures in racehorses.

Severe orbital hematoma with third eyelid swelling and prolapse following a blind maxillary nerve block in a horse.

A 20-year-old quarter horse gelding was presented for routine dental examination. Periodontal disease and luxation of tooth 108 was diagnosed and oral extraction was planned. After an unsuccessful blind maxillary nerve block, it was elected to perform the procedure under total intravenous anesthesia. Following recovery, a focal superficial corneal ulcer, severe retrobulbar swelling, mild exophthalmos, and marked swelling and prolapse of the third eyelid (nictitating membrane) were observed. Clinical signs persisted beyond 48 h despite the use of systemic anti-inflammatories and topical ocular anti-inflammatories and antibiotics. A temporary tarsorrhaphy was subsequently done at 48 h and the horse was discharged after 5 d of hospitalization and regression of clinical signs. Although it is very useful for easing dental extractions, the blind maxillary nerve block is associated with potential complications due to inadvertent vascular puncture. This case report describes a rare complication of prolapse of the third eyelid in a horse after a maxillary nerve block and successful treatment with a temporary tarsorrhaphy. Key clinical message: This case report explains how nictitating membrane swelling and prolapse can occur following a blind maxillary nerve block in the horse and describes treatment with a temporary tarsorrhaphy.

Hématome orbitaire sévère avec gonflement de la troisième paupière et prolapsus à la suite d'un bloc du nerf maxillaire à l'aveugle chez un cheval. Un hongre quarter horse de 20 ans a été présenté pour un examen dentaire de routine. Une maladie parodontale et une luxation de la dent 108 ont été diagnostiquées et une extraction orale a été planifiée. Après l'échec d'un bloc du nerf maxillaire à l'aveugle, il a été décidé d'effectuer la procédure sous anesthésie intraveineuse. Après la guérison, un ulcère cornéen superficiel focal, un gonflement rétrobulbaire sévère, une légère exophtalmie ainsi qu'un gonflement et un prolapsus marqués de la troisième paupière (membrane nictitante) ont été observés. Les signes cliniques ont persisté au-delà de 48 heures malgré l'utilisation d'anti-inflammatoires systémiques et d'anti-inflammatoires oculaires topiques et d'antibiotiques. Une tarsorraphie temporaire a ensuite été réalisée à 48 heures et le cheval est sorti après 5 jours d'hospitalisation et de régression des signes cliniques. Bien qu'il soit très utile pour faciliter les extractions dentaires, le bloc du nerf maxillaire à l'aveugle est associé à des complications potentielles dues à une ponction vasculaire involontaire. Ce rapport de cas décrit une complication rare de prolapsus de la troisième paupière chez un cheval après un bloc nerveux maxillaire et un traitement réussi par tarsorraphie temporaire.Message clinique clé:Ce rapport de cas explique comment un gonflement et un prolapsus de la membrane nictitante peuvent survenir à la suite d'un bloc du nerf maxillaire à l'aveugle chez le cheval et décrit le traitement par tarsorraphie temporaire.(Traduit par Dr Serge Messier).

Long-term follow-up of laryngeal Rhinosporidium seeberi diagnosed by PCR and treated with laser ablation and voriconazole nebulization in a retired thoroughbred polo horse.

A 21-year-old retired polo Argentinian thoroughbred horse from a teaching herd was presented for a routine bronchoalveolar lavage demonstration, during which an incidental finding of a granulomatous mass on the dorsal aspect of the epiglottis was made. Rhinosporidium seeberi was suspected from a histological section obtained from an initial biopsy, and the mass was removed via laser surgery for cytology and PCR. Sequencing of the PCR amplicons confirmed the diagnosis of R. seeberi. A treatment protocol of nebulized voriconazole for 10 d postoperatively was used. Long-term follow-up required 2 more laser surgeries plus oral fluconazole to resolve the remaining fungal spores. However, 2.5 y later, there was no evidence of remaining fungal spores. Key clinical message: Horses from endemic regions can potentially be exposed to R. seeberi. Based on its travel history, this horse may have contracted the infection in South America, California, or Alberta. Treatments administered, including diode laser resection, voriconazole antifungal nebulization, and oral fluconazole administration, were successful but required repeated interventions.

Suivi à long terme du Rhinosporidium seeberi laryngé diagnostiqué par PCR et traité par ablation au laser et nébulisation au voriconazole chez un cheval de polo thoroughbred pur-sang à la retraiteUn cheval thoroughbred argentin de polo retraité de 21 ans, issu d'un troupeau d'enseignement, a été présenté pour une démonstration de lavage broncho-alvéolaire de routine, au cours de laquelle une découverte fortuite d'une masse granulomateuse sur la face dorsale de l'épiglotte a été faite. Rhinosporidium seeberi a été suspecté à partir d'une coupe histologique obtenue à partir d'une biopsie initiale, et la masse a été retirée par chirurgie au laser pour cytologie et PCR. Le séquençage des amplicons PCR a confirmé le diagnostic de R. seeberi. Un protocole de traitement au voriconazole nébulisé pendant 10 jours après l'opération a été utilisé. Le suivi à long terme a nécessité 2 autres interventions chirurgicales au laser et du fluconazole oral pour éliminer les spores fongiques restantes. Cependant, 2,5 ans plus tard, il n'y avait aucune trace de spores fongiques restantes.Message clinique clé:Les chevaux des régions endémiques peuvent potentiellement être exposés à R. seeberi. D'après ses antécédents de voyage, ce cheval pourrait avoir contracté l'infection en Amérique du Sud, en Californie ou en Alberta. Les traitements administrés, notamment la résection au laser à diode, la nébulisation antifongique au voriconazole et l'administration orale de fluconazole, ont été efficaces mais ont nécessité des interventions répétées.(Traduit par Dr Serge Messier).

Preputial lymphangioma in a stallion: First report.

This short communication describes a case of a 30-year-old stallion with a mass on the base of the penis causing paraphimosis. The patient was submitted to anti-inflammatory and diuretic therapy with no signs of improvement, so 16 days after the lesion was detected, the animal was euthanized. Necropsy was performed, and histopathological assessment of the lesion was conducted. The mass was composed primarily of channels and cavernous structures, lined by elongated cells of vascular origin, located in the preputium. The lesion was diagnosed as a preputial lymphangioma. To the authors' best knowledge, the anatomical location of this neoplasm (which is rare in veterinary medicine) has not been previously reported.

Calcification and osseous metaplasia of the meibomian glands of a horse.

OBJECTIVE: To report the clinical history, surgical management, and histologic findings of meibomian gland calcification and osseous metaplasia in a horse. ANIMAL STUDIED: A 21-year-old Selle Français gelding presented with a 9 months history of blepharitis, blepharospasm, and epiphora affecting the right eye. The horse was diagnosed with meibomianitis and impaction with associated granulomas, but not treated surgically for 6 years. PROCEDURES: Physical and ophthalmic examinations, and systemic bloodwork were performed. A diamond burr debridement was performed on a corneal ulceration, and meibomian gland nodules were excised and examined histologically. RESULTS: Multiple firm concretions were associated with the palpebral conjunctiva of each eyelid. The largest nodule (5 × 4 × 10 mm) was excised from the lower right eyelid. Histology revealed dilated meibomian ducts with mineralized inspissated secretions surrounded by fibrosis and osseous metaplasia. Following nodule excision and corneal ulcer resolution, no blepharospasm or epiphora recurred for a follow-up period of 15 months. CONCLUSION: Calcification and osseous metaplasia of the meibomian glands was identified in a Selle Français gelding. It is suspected that inspissated meibomian secretions led to a local granulomatous reaction with secondary dystrophic calcification and osseous metaplasia.

A case of lipogranulomatous conjunctivitis in a horse.

OBJECTIVE: To describe a case of lipogranulomatous conjunctivitis in a horse. ANIMAL STUDIED: A client-owned 12-year-old Standardbred gelding presenting with chronic conjunctivitis and palpebral masses. METHODS: Complete ophthalmic examination, surgical excision, histopathology, and bacterial culture of biopsy samples were performed. RESULTS: Upper and lower eyelids of both eyes were affected, with multiple yellow-to-white nodules on the palpebral conjunctiva, adjacent to the eyelid margin. Nodule removal was achieved via partial tarsal plate excision. Histopathological examination revealed granulomatous inflammation and large droplets of presumed free lipid in the conjunctival lamina propria. The animal was diagnosed with lipogranulomatous conjunctivitis. No postoperative ocular discomfort was observed for months; however, 3 years later, new conjunctival nodules were noticed, requiring a second surgical procedure on three of the eyelids. Transient entropion in the left lower eyelid was observed 2 months after the second surgery, and no recurrence of conjunctival nodules was observed after 18 months of follow-up. CONCLUSION: To our knowledge, this is the first report of lipogranulomatous conjunctivitis in horses.

Endoscopic-guided diagnosis of and interventional stent placement for nasolacrimal duct obstruction in a horse.

OBJECTIVE: To describe the successful use of endoscopy to visualize and place a soft canine ureteral stent to relieve a chronic nasolacrimal duct (NLD) obstruction in a horse. ANIMAL STUDIED: A 7-year-old, Quarter horse gelding. PROCEDURE: Under general anesthesia, retrograde nasolacrimal endoscopy was performed using an 8.5 Fr Storz Flex XC ureteroscope through the nasal punctum (NP). An obstructive web of fibrous tissue was visualized approximately 20 cm proximal to the NP. A 0.035″/150 cm hydrophilic guidewire was passed normograde from the ventral lacrimal punctum and used to puncture the stenotic tissue. Then, a 5.0Fr/70 cm open-end ureteral catheter was threaded normograde over the guidewire and NLD patency was re-established. The catheter confirmed a NLD length of 30 cm and was then removed. A 5.0Fr/22-32 cm Universa© Soft Ureteral Stent was threaded normograde over the guidewire until the loops of the stent were exposed at each end. The guidewire was removed and the stent loops were sutured in place. RESULTS: The stent was withdrawn 1 month after the procedure. Telephone follow-up with the client reported significant improvement in the amount of ocular discharge and decreased sensitivity around the face and ears. CONCLUSION: Endoscopy is a safe and effective procedure allowing for definitive diagnosis of NLD obstruction and to assist in interventional procedures. Placement of a canine indwelling ureteral stent seems to be an effective alternative treatment option for equine NLD obstruction compared to conventional invasive surgical procedures.

Single-incision drilling technique to achieve hemiepiphysiodesis of the distal metacarpus - complications and outcome in 207 foals with metacarpophalangeal varus deformities.

OBJECTIVE: To report the outcome of foals treated for metacarpophalangeal varus deformity with a single-incision drilling technique for hemiepiphysiodesis of the distal lateral metacarpal physis. STUDY DESIGN: Retrospective case-control cohort study. ANIMALS: Thoroughbred foals (n = 207), 171 age- and sex-matched maternal siblings. METHODS: Medical records (2017-2020) were reviewed for signalment, limb(s) treated, location of the surgery, and any reported complications. Follow-up radiographs obtained for the yearling sale were assessed for abnormalities. Horses were matched to maternal siblings using an online database. Sales and racing performance data were compared between cohorts. RESULTS: The average age at the time of surgery was 97 days. The treated limb was the left front in 52, right front in 31, both fronts in 119, unknown in 5. Three horses developed calcinosis circumscripta lesions adjacent to the physis, which were removed successfully. No radiographic abnormalities associated with the surgery site were detected on yearling prepurchase radiographs. There were no differences in sales and racing performance data between treated horses and maternal controls. CONCLUSION: Hemiepiphysiodesis is a safe and effective treatment for metacarpophalangeal varus deformities in foals. No negative effect on sales or racing performance was identified. CLINICAL SIGNIFICANCE: This technique avoids risks, costs, and the need for second surgery associated with an orthopedic implant. The surgeon should be aware of the potential for development of a calcinosis circumscripta lesion with this technique.

Surgical enlargement of the epiploic foramen in horses.

OBJECTIVE: To assess the safety and efficacy of a method for digitally enlarging the caudal aspect of the epiploic foramen (EF). STUDY DESIGN: Healthy horses and clinical cases of EF entrapment (EFE). ANIMALS: Fourteen healthy horses and three clinical cases. METHODS: Through a ventral midline celiotomy under general anesthesia, the EF was enlarged by digital separation of the caudal attachments of the caudate lobe of the liver from right dorsal colon, right kidney, gastropancreatic fold, and pancreas. Healthy horses were euthanized under anesthesia, and the enlarged EF was measured at necropsy. RESULTS: The method used for enlarging the EF did not cause clinically relevant hemorrhage, as determined by visual inspection of the EF in 14 horses at necropsy and by vital parameters under anesthesia in all horses. In clinical cases, EFE was reduced following enlargement of the EF, and no intraoperative complications were encountered. In one clinical case, necropsy at 30 days confirmed partial closure of the enlarged EF. CONCLUSION: The method proposed enlarged the EF safely and effectively. Limitations of the study include the small number of clinical cases and the lack of postoperative follow-up on the healthy horses. CLINICAL SIGNIFICANCE: Enlargement of the EF at its caudal extent should be considered in selected cases of EFE in which manual reduction is difficult or protracted. Although the procedure was safe in this study, knowledge of the anatomy, practice on cadavers, and careful selection of cases with greatest need are recommended before clinical use.