Clinical variability of equine asthma phenotypes and analysis of diagnostic steps in phenotype differentiation.

Background: Equine asthma is a common, non-infectious, chronic lung disease that affects up to 80% of the horse population. Strict phenotyping and identification of subclinically asthmatic horses can be challenging. The aim of this study was to describe equine asthma phenotypes (mild, moderate, and severe asthma) defined by BALF cytology and occurrence of clinical signs in a population of privately owned horses and to identify the variables and examination steps with best discriminative potential.

and Analysis Identify a Detrimental Impact of Neutrophil Extracellular Traps on Eye Structures in Equine Recurrent Uveitis.

Equine recurrent uveitis (ERU) is a common ocular disease of horses and described as a model for human autoimmune uveitis. This immune-mediated, inflammatory condition progressively destroys the eye, ultimately leading to blindness. Genetic and autoimmune factors, next to infections with , are discussed as key factors in the pathogenesis.

Comparative studies on the histological characteristics of equine nasomaxillary aperture and paranasal sinus mucosa considering topographic and age-related differences.

Background: Horses may acquire a range of paranasal sinus diseases. Clinical studies show slight differences regarding anatomical regions and age. Histopathological examination of tissue samples could play an important role in the diagnostic process.

Magnetic resonance imaging and computed tomography of equine cheek teeth and adjacent structures: comparative study of image quality in horses in vivo, post-mortem and frozen-thawed.

Background: The use of cadavers for radiology research methodologies involving subjective image quality evaluation of anatomical criteria is well-documented. The purpose of this method comparison study was to evaluate the image quality of dental and adjacent structures in computed tomography (CT) and high-field (3 T) magnetic resonance (MR) images in cadaveric heads, based on an objective four-point rating scale. Whilst CT is a well-established technique, MR imaging (MRI) is rarely used for equine dental diagnostics.

Neutrophil Extracellular Traps in the Pathogenesis of Equine Recurrent Uveitis (ERU).

Equine recurrent uveitis (ERU) is considered one of the most important eye diseases in horses and typically appears with relapsing inflammatory episodes without systemic effects. Various disorders have been described as an initial trigger, including infections. Independent of the initiating cause, there are numerous indications that ERU is an immune-mediated disease.

Cytological Examination of Secretions From the Paranasal Sinuses in Horses.

The objective of this study was to determine whether the assessment of cytological features of secretions from the paranasal sinuses represents a useful diagnostic tool in equine sinusitis to distinguish between different etiologies. Secretion samples from 50 horses with sinusitis and 10 healthy horses were taken transendoscopically from the drainage angle of the nasomaxillary aperture using a Swing Tip catheter. An additional direct sample from the caudal maxillary sinus was taken from all healthy horses after trephination.

A prospective study on the microbiological examination of secretions from the paranasal sinuses in horses in health and disease.

Background: Diagnostics in equine sinusitis can be challenging and often require a combination of different imaging tools to ascertain its underlying aetiology. The bacterial flora of healthy and diseased paranasal sinuses, respectively, has only sporadically been assessed in horses. The objectives of this study were to determine whether assessment of microbiological features of secretions from the paranasal sinuses displays a useful diagnostic tool in equine sinusitis to distinguish between different aetiologies.

Intraocular lens power calculation for the equine eye.

Background: Phacoemulsification and intraocular lens (IOL) implantation during cataract surgery in horses occur with increasing frequency. To reduce the postoperative refractive error it is necessary to determine the proper IOL power. In the present study retinoscopy, keratometry and ultrasonographic biometry were performed on 98 healthy equine eyes from 49 horses.

Comparison of computed tomography and high-field (3.0 T) magnetic resonance imaging of age-related variances in selected equine maxillary cheek teeth and adjacent tissues.

Background: Modern imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI) have the advantage of producing images without superimposition. Whilst CT is a well-established technique for dental diagnostics, MRI examinations are rarely used for the evaluation of dental diseases in horses. Regarding equine endodontic therapies which are increasingly implemented, MRI could help to portray changes of the periodontal ligament and display gross pulpar anatomy.

Controlled mechanical ventilation with constant positive end-expiratory pressure and alveolar recruitment manoeuvres during anaesthesia in laterally or dorsally recumbent horses.

Objective: To compare the effects of controlled mechanical ventilation (CMV) and constant positive end-expiratory pressure (PEEP) and interposed recruitment manoeuvres (RMs) with those of CMV without PEEP on gas exchange during general anaesthesia and the early recovery period.

Study Design: Prospective, randomized clinical trial.

Animals: A total of 48 Warmblood horses undergoing elective surgery in lateral (Lat) (n = 24) or dorsal (Dors) (n = 24) recumbency.

Comparison of image quality and in vivo appearance of the normal equine nasal cavities and paranasal sinuses in computed tomography and high field (3.0 T) magnetic resonance imaging.

Background: Computed tomography (CT) is a well-established imaging technique in the diagnostics of equine sinunasal disease. High-field magnetic resonance imaging (MRI) is becoming more readily available in equine veterinary medicine. MRI is appreciated for its superior ability to depict soft tissues with high contrast.

Application of in vivo microdialysis for investigation of unbound drug concentrations of intravenously administered sulfadimidine in the paranasal sinus mucosa of horses.

Objective: To monitor concentrations of sulfadimidine in the paranasal sinus mucosa (PSM) of unsedated horses following IV administration of trimethoprim-sulfadimidine via in vivo microdialysis.

Animals: 10 healthy adult horses.

Procedures: Concentric microdialysis probes were implanted into the subepithelial layers of the frontal sinus mucosa of standing sedated horses.

Evaluation of ultrasound velocity in enucleated equine aqueous humor, lens and vitreous body.

Background: Sonographic ophthalmic examinations have become increasingly important in veterinary medicine. If the velocity of ultrasound in ocular tissues is known, the A-mode ultrasound method may be used to determine the axial intraocular distances, such as anterior chamber depth, lens thickness, axial length of the vitreous and axial globe length, which are required for intraocular lens (IOL) power calculations. To the authors' knowledge, the velocity of ultrasound in the ocular tissues of the horse was not previously determined.

Objective classification of different head and neck positions and their influence on the radiographic pharyngeal diameter in sport horses.

Background: Various head and neck positions in sport horses are significant as they can interfere with upper airway flow mechanics during exercise. Until now, research has focused on subjectively described head and neck positions. The objective of this study was to develop an objective, reproducible method for quantifying head and neck positions accurately.

Pharyngeal diameter in various head and neck positions during exercise in sport horses.

Background: In equine athletes, dynamic stenotic disorders of the upper airways are often the cause for abnormal respiratory noises and/or poor performance. There are hypotheses, that head and neck flexion may influence the morphology and function of the upper airway and thus could even induce or deteriorate disorders of the upper respiratory tract. Especially the pharynx, without osseous or cartilaginous support is prone to changes in pressure and airflow during exercise.

Transendoscopic laser surgery to correct nasopharyngeal obstruction caused by head flexion in horses.

Objective: To determine outcome after transendoscopic laser fenestration of the median septum and removal of the salpingopharyngeal fold of the guttural pouch on nasopharyngeal obstruction caused by poll flexion in Warmblood horses.

Study Design: Clinical study.

Animals: Horses (n = 9).

The sinonasal communication in the horse: examinations using computerized three-dimensional reformatted renderings of computed-tomography datasets.

Background: Sinusitis is a common disease in the horse. In human medicine it is described, that obstruction of the sinonasal communication plays a major role in the development of sinusitis. To get spatial sense of the equine specific communication ways between the nasal cavity and the paranasal sinuses, heads of 19 horses, aged 2 to 26 years, were analyzed using three-dimensional (3D) reformatted renderings of CT-datasets.

[Influence of atracurium on cardiovascular parameters in horses undergoing vitrectomy during general anaesthesia, and on recovery duration and quality].

Objective: In most ocular procedures, a central position of the eye is necessary. This can be achieved using a deep plane of anaesthesia, locoregional blocks or with neuromuscular blocking agents. The aim of this study was to evaluate the influence of atracurium on cardiovascular parameters, and on recovery quality and duration in horses.

A genome-wide association study identifies risk loci to equine recurrent uveitis in German warmblood horses.

Equine recurrent uveitis (ERU) is a common eye disease affecting up to 3-15% of the horse population. A genome-wide association study (GWAS) using the Illumina equine SNP50 bead chip was performed to identify loci conferring risk to ERU. The sample included a total of 144 German warmblood horses.

Using semi-automated segmentation of computed tomography datasets for three-dimensional visualization and volume measurements of equine paranasal sinuses.

The system of the paranasal sinuses morphologically represents one of the most complex parts of the equine body. A clear understanding of spatial relationships is needed for correct diagnosis and treatment. The purpose of this study was to describe the anatomy and volume of equine paranasal sinuses using three-dimensional (3D) reformatted renderings of computed tomography (CT) slices.

Non-genomic action of beclomethasone dipropionate on bronchoconstriction caused by leukotriene C4 in precision cut lung slices in the horse.

Background: Glucocorticoids have been proven to be effective in the therapy of recurrent airway obstruction (RAO) in horses via systemic as well as local (inhalative) administration. Elective analysis of the effects of this drug on bronchoconstriction in viable lung tissue offers an insight into the mechanism of action of the inflammatory cascade occurring during RAO which is still unclear. The mechanism of action of steroids in treatment of RAO is thought to be induced through classical genomic pathways.

Genome-wide linkage and association analysis identifies major gene loci for guttural pouch tympany in Arabian and German warmblood horses.

Equine guttural pouch tympany (GPT) is a hereditary condition affecting foals in their first months of life. Complex segregation analyses in Arabian and German warmblood horses showed the involvement of a major gene as very likely. Genome-wide linkage and association analyses including a high density marker set of single nucleotide polymorphisms (SNPs) were performed to map the genomic region harbouring the potential major gene for GPT.

Intermittent positive pressure ventilation with constant positive end-expiratory pressure and alveolar recruitment manoeuvre during inhalation anaesthesia in horses undergoing surgery for colic, and its influence on the early recovery period.

Objective: To compare, ventilation using intermittent positive pressure ventilation (IPPV) with constant positive end-expiratory pressure (PEEP) and alveolar recruitment manoeuvres (RM) to classical IPPV without PEEP on gas exchange during anaesthesia and early recovery.

Study Design: Prospective randomized study.

Animals: Twenty-four warm-blood horses, weight mean 548 ± SD 49 kg undergoing surgery for colic.

Influence of modified open lung concept ventilation on the cardiovascular and pulmonary function of horses during total intravenous anaesthesia.

The influence of a modified open lung concept (mOLC) on pulmonary and cardiovascular function during total intravenous anaesthesia (TIVA) in horses was evaluated. Forty-two warmblood horses (American Society of Anesthesiologists class 1 to 2), scheduled for elective surgery (mean [sd] weight 526 [65] kg, age 6.4 [5.