Equine Suture Exostosis: A Review of Cases from a Multicenter Retrospective Study.

Suture exostosis is an intriguing and not uncommon pathology that has to be included in the differential diagnosis for horses with swelling of the head. Although several singular case reports have been published, no large case series is available. The aim of this study is to report a multicentric retrospective collection of suture exostosis cases. Data concerning horses with suture exostosis in the facial region were collected retrospectively. Information regarding breed, age, gender, history, imaging findings, initiated treatment, response to treatment and follow up was recorded. One hundred and five cases of various breeds were reported. Analysis revealed the cases could be grouped into four entities: 45 developed following sino-nasal surgery, 23 following trauma, seven with underlying sinus pathology and 25 idiopathic. Treatment consisted of sequestra removal, plate fixation, antimicrobial and anti-inflammatory drugs or no treatment. Whereas initial localized pain fades within few days or weeks, resolution or reduction of the swelling was obtained in most cases after 3 months to 1.5 years. The etiopathogenesis of suture exostosis seems to consist of different entities. Identification of an underlying cause, particularly the presence of a bone sequester and infection is important to speed up resolution and before concluding an idiopathic case. When performing sinusotomies, it is important to provide as little trauma as possible to the surgical site in order to prevent suture exostosis as a complication.

Surgical enlargement of the nasomaxillary aperture and transnasal conchotomy of the ventral conchal sinus: Two surgical techniques to improve sinus drainage in horses.

OBJECTIVE: To evaluate 2 surgical techniques for establishing and/or improving paranasal sinus drainage in cadaver heads and horses with sinusitis and evaluate the feasibility of postoperative transnasal sinus endoscopy. STUDY DESIGN: Ex vivo study (equine cadaver heads) and case series. SAMPLE POPULATION: Nine adult equine cadaver heads and 8 horses with recurrent sinusitis. METHODS: For the ex vivo study, the following procedures were performed on 9 cadaver heads: preoperative and postoperative computed tomography (heads 1-6), endoscopy-guided transnasal conchotomy of the ventral conchal sinus (TCVCS) and surgical enlargement of the nasomaxillary aperture (SENMAP) on opposite sides (heads 1-3), combined TCVCS and SENMAP on both sides (heads 4-9), evaluation of sinus drainage before and after surgery (heads 7-9), and postoperative transnasal endoscopy (heads 4-9). For the case series, 8 horses with secondary sinusitis were treated in standing position with SENMAP and/or TCVCS and postoperative transnasal endoscopy. RESULTS: Sinonasal communications were successfully created in all cadavers and affected live horses. Transnasal endoscopy of all sinuses except the middle conchal sinus was possible in heads 4-9 and in all clinical cases. Sinus drainage was improved (P = .028) by combining techniques. Blood loss in live horses ranged from 0.5-5.5 L (1.95 ± 1.5) per horse. Sinusitis resolved in all affected horses during follow-up of 3.2-25.5 months (13.5 ± 8.5). CONCLUSION: Transnasal conchotomy of the ventral conchal sinus and SENMAP consistently created large sinonasal communications, facilitating sinus endoscopy and improving sinus drainage. CLINICAL SIGNIFICANCE: Transnasal conchotomy of the ventral conchal sinus and SENMAP are viable options to treat horses with sinusitis and anatomical obstructions of the sinonasal communications.

Progressive ossifying paranasal sinus mass of suspected traumatic origin in a mare: Surgical treatment and follow-up.

This report describes a case of a multilobular, osseous mass including parts of the right orbit, concho frontal sinus and right ventral and dorsal conchal sinuses that developed after a traumatic insult to the right maxillary sinus 4 years prior to presentation. Surgical removal of the mass including parts of the bony orbit and long-term outcome are reported.

Masse des sinus paranasaux à ossification progressive d'origine traumatique soupçonnée chez une jument : traitement chirurgical et suivi. Ce rapport décrit une masse multilobulaire et osseuse comprenant des parties de l'orbite droite, des cornets nasaux frontaux et des sinus ventral et dorsal droits qui s'est développée après un traumatisme du sinus maxillaire droit 4 années avant la présentation. L'ablation chirurgicale de la masse, incluant des parties de l'orbite osseuse et les résultats à long terme sont signalés.(Traduit par Isabelle Vallières).

Bacterial meningitis after sinus surgery in five adult horses.

OBJECTIVE: To report meningoencephalitis as a complication after paranasal sinus surgery in 5 horses. STUDY DESIGN: Case series. ANIMALS: Adult horses (n = 5). METHODS: Medical records (2005-2010) of 5 horses that developed neurologic signs after sinus surgery were reviewed to identify potential risk factors, cause(s), or common pathways for infection. RESULTS: Underlying diseases were primary (n = 1) and secondary sinusitis (4) because of apical dental infection (1), sinus cyst (2), or masses in the ethmoturbinate region (2). Horses were treated by conventional surgical approaches and aftercare including repeated sinus lavage. Four horses had undulating pyrexia postoperatively despite antimicrobial therapy. All horses developed neurologic signs, eventually unresponsive to treatment. Suppurative meningoencephalitis was diagnosed macro- and/or microscopically on necropsy in all horses. CONCLUSION: Meningitis is a rare but fatal complication after sinus surgery in horses.

Identification and characterization of methicillin-resistant Staphylococcus aureus (MRSA) from Austrian companion animals and horses.

The aim of this study was to investigate the antimicrobial resistance, resistance gene patterns and genetic relatedness of a collection of Austrian methicillin-resistant Staphylococcus aureus (MRSA) isolates from companion animals and horses. A total of 89 non-repetitive MRSA isolates collected during routine veterinary microbiological examinations from April 2004 to the end of 2012, and one isolate from 2013 were used for this study. The presence of mecA and other resistance genes was confirmed by PCR. Isolates were genotyped by spa typing, two multiple-locus variable-number tandem repeat analyses (MLVA) analyses, SCCmec typing and multilocus sequence typing (MLST). PCR targeting Panton-Valentine leukocidin (PVL) and detection of staphylococcal enterotoxins (SE), toxic shock syndrome toxin (TSST) was performed using PCR assays. Antimicrobial susceptibility testing was performed. Five sequence types (STs-ST398, ST254, ST22, ST5 and ST1), SCCmec types II, IVa, V, and non-type-abele, 8 spa-types (t003, t011, t036, t127, t386, t1348, and t4450), and two isolates could not be assigned, 21 MLVA-14Orsay types Multiplex-PCR MLVA (mMLVA) displayed 17 different MLVA types. The present study is the most comprehensive dealing with MRSA from Austrian companion animals and horses. The results confirm that MRSA ST398 is present in a wide range of animal species and is predominant especially in horses. In other companion animals it is unclear whether the infections with the different MRSA isolates investigated in the present study truly represents a rare phenomenon or may be an emerging problem in companion animals.

Kinematic analysis of equine masticatory movements: comparison before and after routine dental treatment.

The objective of this study was to compare masticatory movements before and after dental treatment using kinematic analysis. The masticatory movements of 15 adult Warmblood horses with mild dental pathology chewing standardised hay were recorded on three consecutive days before and three times after (days 7, 21, 28) dental correction. The results of the leading mandibular tracking marker, located at the caudal edge of the inter-mandibular suture, were compared statistically. Reproducibility of measurements prior to dental treatment was excellent (P<0.05). Rostrocaudal mandibular motion was significantly reduced after dental correction (9±2mm vs. 8±2mm; P=0.046). Oscillations during the power stroke were significantly reduced after dental correction (R(2)=98.3%±0.3 vs. 98.8%±0.3; P=0.050). Although significant changes were observed in individual horses, the overall results of lateral and dorsoventral mandibular motion did not reveal significant differences. In conclusion, kinematic analysis of masticatory movements provided reproducible results and may be useful to evaluate changed movement patterns following dental correction.

The use of oral endoscopy for detection of cheek teeth abnormalities in 300 horses.

The main objective of this study was to evaluate an endoscopic examination protocol for routine dental examination in horses. The oral cavities of 300 standing, sedated horses were examined under field and hospital conditions with a rigid endoscope using a standardised technique that included examination of the occlusal, lingual (palatal) and buccal surfaces of all cheek teeth rows. The most common cheek teeth abnormalities detected were sharp enamel edges (present in 96.3% of horses), focal overgrowths (64.3%), fissure fractures (54.3%), diastemata (24.3%) and infundibular hypoplasia/caries (48.3%). Rigid endoscopy of the equine oral cavity was found to be a safe non-invasive diagnostic technique that appeared to be superior to clinical oral examination for detecting subtle cheek teeth changes.

A long-term study of apicoectomy and endodontic treatment of apically infected cheek teeth in 12 horses.

The aim of this study was to evaluate the long-term results of apicoectomy and retrograde endodontic treatment in 12 horses with apical cheek teeth infections. The affected apices were removed using a diamond bur mounted on a dental drill, and after pulp removal the root canals were filed with Hedstrøm files and then alternately flushed with sodium hypochlorite, hydrogen peroxide and alcohol. The pulp canals were dried and filled with endodontic cement and gutta-percha points. An undercut was made in the apical aspect of the root canals that were then sealed with self-curing glass ionomer cement. Follow up information was obtained 38-67 months following treatment and indicated that the treatment had been successful in 7/12 horses (58%), partially successful in 2 horses (17%) and unsuccessful in 3 (25%). With good case selection, apicoectomy can preserve a proportion of apically infected cheek teeth. The use of advanced imaging techniques and improved surgical techniques could increase the success rate.

Equine odontoclastic tooth resorption and hypercementosis.

A poorly described, painful disorder of incisor and canine teeth, variably causing periodontitis, with resorptive or proliferative changes of the calcified dental tissues, has recently been documented in aged horses. No plausible aetiopathogenesis for this syndrome has been recorded. Eighteen diseased teeth from eight horses were examined grossly and microscopically and showed the presence of odontoclastic cells by tartrate resistant acid phosphatase (TRAP) staining. A chronological sequence of odontoclastic resorption followed by hypercementosis was demonstrated and, consequently, the term equine odontoclastic tooth resorption and hypercementosis (EOTRH) is proposed for this disorder. EOTRH shares many features with similar dental syndromes described in humans and cats. An aetiological hypothesis proposes mechanical stress of the periodontal ligament as the initiating factor.

Mandibular condylectomy and meniscectomy for the treatment of septic temporomandibular joint arthritis in a horse.

OBJECTIVE: To report use of mandibular condylectomy for treatment of advanced degenerative joint disease of the temporomandibular joint (TMJ) caused by sepsis. DESIGN: Clinical case report. ANIMALS: Two-year-old Noriker filly. METHODS: Computed tomography (CT) was used to confirm advanced degenerative joint disease of the left TMJ and for follow-up after mandibular condylectomy and removal of necrotic meniscus. RESULTS: Painful swelling (3 weeks duration) with drainage located just caudal to the left lateral canthus of the eye was associated with atrophy of the left masseter muscle, masticatory problems, and inappetence. There was incisor malocclusion with a 1.4 cm resting lateral mandibular deviation to the right and inability to open the mouth more than a few centimeters. Left mandibular condylectomy combined with meniscectomy and thorough debridement of the septic left TMJ resulted in resolution of clinical signs and complete return of function. Streptococcus zooepidemicus, intermediately resistant to penicillin and subsequently to enrofloxacin, was isolated from the wound. Regeneration of a mandibular "pseudocondyle" was evident on CT at 4 months. At 4 months and 1 year the filly had maximal mouth opening >10 cm and no malocclusion. CONCLUSION: Mandibular condylectomy can be used to facilitate management of septic TMJ arthritis. There was no radiologic or clinical evidence of TMJ ankylosis >1 year after meniscal removal. CLINICAL RELEVANCE: Mandibular condylectomy, including meniscectomy, is an acceptable treatment option for advanced TMJ septic arthritis and allowed return of normal masticatory function.

[First-time endoscopic detection of larvae of Gasterophilus spp. in the oral cavity in 14 warmblood horses]. / Erstmaliger endoskopischer Nachweis von Gasterophilus-Larven in der Mundhöhle bei 14 Warmblutpferden.

Intraoral endoscopy is used as a standard diagnostic technique at the reporting clinics in horses presented with stomatological problems. Endoscopy of the oral cavity was performed using a chip camera, camera control unit, xenon cold light source and a rigid endoscope. In a three year period (2002 to 2004), second instars of Gasterophilus spp. were diagnosed in 14 warmblood horses 2 to 17 years of age. All horses were presented with masticatory problems or problems accepting the bit. In one horse oesophageal obstruction occurred in the course of larval migration. Oral endoscopy can not only be used for the diagnosis of dental disease but also for detection of instars of Gasterophilus spp. in the interdental spaces of maxillary cheek teeth.

CT features of alveolitis and sinusitis in horses.

Sinusitis is a common disorder in horses and may result from trauma, dental diseases, or space-occupying lesions. Radiography can only provide a limited amount of information. Computed tomography (CT) has been documented as an alternative imaging method. Eighteen horses (mostly Warmblood) with signs of chronic sinusitis were examined preoperatively with CT to assist in diagnosis of the underlying cause. There was a group of common CT features in horses with dental disease and sinusitis. The first molar was the most frequently affected maxillary cheek tooth. Hypoattenuation of the cementum, destruction of the enamel, and filling of the infundibular cavity with gas were the most frequent CT findings associated with caries. Gas bubbles within the bulging root area or fragmentation of the root in combination with swelling of the adjacent sinus lining were the most important CT features of dental decay. CT findings associated with sinusitis included excessive thickening of the respiratory epithelium in the rostral maxillary sinus; the caudal maxillary sinus was less often involved. The infraorbital canal, the nasomaxillary duct, and the frontomaxillary aperture were usually involved. The maxillary bone, however, especially the facial crest, was involved in nearly every horse, being characterized by endosteal sclerosis, thickening, periosteal reaction, and deformation leading to facial swelling in chronic infections. CT images allowed identification of involvement of individual teeth more clearly to reveal the diseased one for treatment. Three-dimensional imaging allowed improved understanding of the extent and severity of the pathologic change.