Extensive rostral mandibulectomy for treatment of ameloblastoma in a horse.

OBJECTIVE: To report long-term outcome in a mare that had extensive rostral mandibulectomy to remove an ameloblastoma. STUDY DESIGN: Clinical report. ANIMALS: A 21-year-old mare. METHODS: An ameloblastoma, located in the rostral aspect of the mandible, was removed by complete en-bloc resection of the tumor, removing most of the mandibular symphysis. RESULTS: The day after surgery, the remaining mandibular symphysis (<5 mm) fractured causing marked instability of the hemi-mandibles. Partial wound dehiscence occurred 5 days after surgery; however, the mare was able to eat well and the incision healed within 2 weeks. At 18 months, there was bony fusion of the hemi-mandibles and mild protrusion of the tongue. CONCLUSION: Extensive rostral mandibulectomy (up to the caudal edge of the mandibular symphysis) can apparently be performed in a horse without internal or external stabilization, and yield a cosmetic and functional outcome.

Partial ceratohyoidectomy as surgical treatment for horses with temporohyoid osteoarthropathy: 10 cases (2010-2021).

OBJECTIVE: To describe outcomes of horses with temporohyoid osteoarthropathy (THO) treated with partial ceratohyoidectomy. ANIMALS: 10 client-owned horses. PROCEDURES: Medical records from 2 institutions were examined for records of horses with THO treated with partial ceratohyoidectomy between 2010 and 2021. History, signalment, clinical signs, diagnostics, medications, and surgery-related details were recorded. Horses with a minimum of 6 months follow-up were recruited for neurologic and imaging examinations in the hospital or field where radiography of the basihyoid-ceratohyoid articulation were performed along with CT, when available. RESULTS: 10 horses with THO were included (9 unilateral; 1 bilateral). Nine planned partial ceratohyoidectomies were performed in 8 horses, whereas 2 horses had preoperatively planned complete ceratohyoidectomies transitioned to partial ceratohyoidectomies during surgery due to intraoperative complications. Postoperative complications occurred mostly in transitioned surgeries (obstructed airway, tongue mobility issues, and incisional hemorrhage), whereas only 1 horse with a planned ceratohyoidectomy had postoperative complication of rhabdomyolysis. All complications resolved before hospital discharge. Neurologic signs improved in all 10 horses, with 2 showing complete resolution. Nine horses were available for radiographic follow-up, 6 of which also had head CT scans. A space between the ceratohyoid and basihyoid bones was measurable on radiography in all 9 horses, and was confirmed on CT. Three horses demonstrated proliferation of either ceratohyoid or basihyoid bones. The 9 horses with unilateral disease returned to previous work, and the horse with bilateral disease was retired. CLINICAL RELEVANCE: Partial ceratohyoidectomy is a surgical option for treatment of THO that provides similar clinical outcomes to published reports on ceratohyoidectomy.

Small intestinal strangulation caused by a mesodiverticular band and diverticulum on the mesenteric border of the small intestine in a horse.

A 4-year-old Quarter horse stallion was presented for acute abdominal pain. Exploratory celiotomy revealed a mesenteric diverticulum of the jejunum and mesodiverticular band that were associated with small intestinal strangulation. Resection and anastomosis were performed. A second celiotomy was performed due to adhesions. The horse recovered completely and returned to training.

Palmar/plantar approach for radiographic-guided injection of the equine distal interphalangeal joint collateral ligament insertion.

There are limited radiographic-guided injection techniques of the insertion of the distal interphalangeal joint (DIPJ) collateral ligaments. The objective of this study was to develop and evaluate a palmar/plantar radiographic-guided injection of the collateral ligament insertion in cadavers. Fifty limbs were used to develop the technique and 24 additional limbs were used to evaluate accuracy. An 18 G, 9 cm spinal needle was placed in the depression between the palmar digital neurovascular bundle and arch of the ungular cartilage with dorsodistal advancement towards the distal phalanx collateral fossa. Radiographs verified ideal needle location on the proximal border of the distal phalanx at the collateral fossa. Dye was injected. Hoof walls were partially removed and collateral ligaments were dissected with needles in place to determine needle and dye location. Accuracy of needle placement into the insertion of the DIPJ collateral ligament was 41/48 (85 per cent), with lower accuracy of dye within the ligament (34/48; 71 per cent). Dye entered the DIPJ in 2/48 injections, but dye entered periligamentous structures in 22/48 (46 per cent) injections. A palmar/plantar radiographic-guided injection of the insertion of the DIPJ collateral ligament had high accuracy rate with low injection rate of the DIPJ in cadavers.

Progression of mycosis of the auditory tube diverticulum (guttural pouch) after arterial occlusion in a horse with contralateral temporohyoid osteoarthropathy.

CASE DESCRIPTION: A 6-year-old Appaloosa mare was examined because of inappetance, difficulty eating, and swelling and mucopurulent discharge in the right eye. CLINICAL FINDINGS: Results of a CBC and serum bio-chemical analysis revealed no important findings. Ophthalmologic examination revealed scarring and ulceration of the superficial layers of the cornea. Endoscopic examination of the upper portion of the respiratory tract and auditory tube diverticula (guttural pouches) revealed abnormal thickness of the right stylohyoid bone and a plaque suggestive of mycotic growth on the left internal carotid artery. Radiographic examination revealed right-sided otitis media. Temporohyoid osteoarthropathy in the right guttural pouch and mycosis in the left guttural pouch were diagnosed. TREATMENT AND OUTCOME: Ceratohyoidectomy of the right stylohyoid bone was performed, and the left internal carotid artery was occluded via placement of stainless steel spring embolization coils. The mare regained the ability to eat without difficulty and improved clinically for approximately 4 weeks. However, the mare returned to the medical center 53 days after surgery with left-sided Horner syndrome, atrophy of the right side of the tongue, and a 3-week history of dysphagia and weight loss. Endoscopic evaluation revealed progression of mycotic growth in the left guttural pouch. The mare was euthanatized. CLINICAL RELEVANCE: Although the mycotic lesion in the left guttural pouch was an incidental finding at the time of initial examination, the lesion progressed to cause dysphagia and Horner syndrome after occlusion of the left internal carotid artery, a treatment that is typically associated with resolution of guttural pouch mycosis. Arterial occlusion is not necessarily a reliable method of resolving guttural pouch mycosis.

Risk factors associated with fecal Salmonella shedding among hospitalized horses with signs of gastrointestinal tract disease.

OBJECTIVE: To estimate prevalence of and identify risk factors for fecal Salmonella shedding among hospitalized horses with signs of gastrointestinal tract disease. DESIGN: Cross-sectional study. ANIMALS: 465 hospitalized horses with gastrointestinal tract disease. PROCEDURE: Horses were classified as positive or negative for fecal Salmonella shedding during hospitalization by means of standard aerobic bacteriologic methods. The relationship between investigated exposure factors and fecal Salmonella shedding was examined by means of logistic regression. RESULTS: The overall prevalence of fecal Salmonella shedding was 13%. Salmonella serotype Newport was the most commonly isolated serotype (12/60 [20%]), followed by Anatum (8/60 [13%]), Java (13%), and Saint-paul (13%). Foals with gastrointestinal tract disease were 3.27 times as likely to be shedding Salmonella organisms as were adult horses with gastrointestinal tract disease. Adult horses that had been treated with antimicrobial drugs prior to hospitalization were 3.09 times as likely to be shedding Salmonella organisms as were adult horses that had not been treated with antimicrobial drugs prior to hospitalization. Adult horses that underwent abdominal surgery were 2.09 times as likely to be shedding Salmonella organisms as were adult horses that did not undergo abdominal surgery. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that a history of exposure to antimicrobial drugs prior to hospitalization and abdominal surgery during hospitalization were associated with Salmonella shedding in adult horses with gastrointestinal tract disease. Foals with gastrointestinal tract disease were more likely to shed Salmonella organisms than were adult horses with gastrointestinal tract disease.

Abordaje translaberíntico y rehabilitación vestibular: eficacia en el tratamiento de la disfunción vestibular en pacientes con schwannoma vestibular / Translabyrinthine approach and vestibular rehabilitation: efficacy in the treatment of vestibular dysfunction in patients with vestibular schwannoma

Introducción: En los schwannomas vestibulares (SV), la incidencia de disfunción vestibular como principal síntoma es del 10%, sin embargo, producen un notorio impacto en la calidad de vida de los pacientes. Objetivo: Evaluar el impacto funcional que produce la exéresis de SV por via translaberintica y la rehabilitación vestibular sobre los síntomas vestibulares, en los pacientes tratados en nuestro hospital. Material y Métodos: Se realizó un análisis prospectivo de 2 pacientes con diagnóstico de SV y disfunción vestibular agregada. En ambos pacientes, se realizó la resección a través de un abordaje translaberíntico. Los pacientes fueron evaluados funcionalmente antes y después de la cirugía. El impacto de la misma sobre la calidad de vida se evalúo mediante la Escala de Discapacidad por Mareo (DHI). Todos los pacientes realizaron un plan de rehabilitación vestibular personalizado y a los 12 meses postoperatorios presentaron una mejoría clínica significativa en comparación con el preoperatorio. Discusión: Las posibles opciones de tratamiento en estos pacientes resultan limitadas. En la literatura, se ha demostrado que la laberintectomía es un tratamiento eficaz para el tratamiento de síntomas vestibulares persistentes e incapacitantes, en los pacientes sin audición funcional. La calidad de vida de los mismos es reducida, y mejoraría significativamente después de la cirugía translaberintica y de un programa personalizado de rehabilitación vestibular. Conclusión: Debido a su eficacia comprobada, el abordaje translaberíntico y la resección de la lesión, acompañado de la realización un programa de rehabilitación vestibular, como estrategia de tratamiento para estos pacientes debe ser considerado.

Introduction: The incidence of disabling vestibular symptoms in vestibular schwannoma patients has been reported at roughly 10%. Despite their relative rarity, however, such symptoms can lead to physical and social limitations and reduce patients' quality of life. Unfortunately, published evidence on possible treatment options for vestibular schwannoma patients with disabling vestibular symptoms is limited. Objective: To report the functional impact of trans-labyrinthine microsurgery and vestibular rehabilitation, performed at our hospital, in two vestibular schwannoma patients with disabling vestibular symptoms. Methods: A prospective analysis was performed of two patients with a unilateral vestibular schwannoma, without serviceable hearing in their affected ear, and severely handicapped by attacks of rotatory vertigo and constant dizziness. Trans-labyrinthine surgery, with complete tumor resection, was performed in both patients. Preoperative and postoperative quality of life was measured using Dizziness Handicap Inventory (DHI) scores. Both patients also underwent a customized vestibular rehabilitation program and had a final evaluation 12 months post-operatively. Results: Relative to their preoperative evaluation, both patients experienced significant clinical improvement that persisted through 12 months of post-operative follow-up. Conclusions: Consistent with the few prior reports already published, we found that surgical removal of vestibular schwannomas by trans-labyrinthine surgery and vestibular rehabilitation was safe and effective for persistent, disabling vestibular symptoms. Postoperative vertigo and quality of life both improved significantly when microsurgery was combined with a personalized vestibular rehabilitation program. Disabling vestibular symptoms that impair quality of life in patients with vestibular schwannoma without serviceable hearing in the affected ear should be considered for trans-labyrinthine microsurgery and personalized vestibular rehabilitation.