Imaging techniques in horses encompass a range of diagnostic tools used to visualize the internal structures and systems of equine patients. These techniques assist in the diagnosis, monitoring, and treatment planning of various conditions affecting horses. Common imaging modalities include radiography (X-rays), ultrasonography, magnetic resonance imaging (MRI), and computed tomography (CT). Each technique offers unique advantages in terms of resolution, depth of penetration, and the type of tissues that can be examined. For instance, radiography is frequently used for assessing bone structures, while ultrasonography is often employed for soft tissue evaluation. MRI and CT provide detailed cross-sectional images, aiding in the assessment of complex anatomical regions. This page compiles peer-reviewed research studies and scholarly articles that explore the application, advancements, and comparative efficacy of imaging techniques in equine veterinary medicine.
Maia BT, Vendruscolo CDP, de Souza AF, Zoppa ALDV.The neurovascular bundle of the equine distal cannon can dynamically vary with limb position, and this can affect the performance of low 4- or 6-point block. This study aims to identify and describe the anatomical position and variations of the lateral and medial palmar/plantar nerve at the metacarpal/metatarsal distal level in horses by ultrasonography. Eight mares underwent ultrasound examination on the lateral and medial palmar/plantar sides of the metacarpus/metatarsus. Images were obtained for measurements of the cross-sectional area of the nerve, distances between the nerve and the skin ...
Deacon LJ, Navas de Solis C, Richardson DW, Polkes A, Reef VB.• An ACF developed in a hospitalized horse following orthopedic surgery. • Spontaneous closure of the ACF occurred 6 weeks after initial diagnosis. • Echocardiography is the primary imaging modality to confirm the presence of ACF in equids. [Figure: see text]
Emmert BJ, Robison CI, Pritchard A, Nielsen BD.Digital radiographs are common for estimating bone mineral content (BMC) in horses with radiographic bone aluminum equivalents (RBAE). Processing algorithms are used to produce clearer images of digital radiographs in clinical settings, but this distorts RBAE. This study compared RBAE from digital radiographs to BMC from bone ash, and physical and digital morphology measurements. Digital radiographs were taken of six third metacarpals (MCIII) from equine cadavers with an aluminum step wedge penetrometer. A 2-cm transverse section of bone was digitally analyzed and excised from each MCIII. For ...
Herren FL, Gerber V, Meier R, Schweizer-Gorgas D, Klopfenstein Bregger MD.The volumes of equine teeth may change considerably over time for several reasons including domestication, routine dental floating, and the hypsodont and anelodont nature of the teeth. Cone beam computed tomography (CBCT) of the head is routinely performed in standing horses and, in this proof of concept study, the feasibility of measuring tooth volume from CBCT datasets was determined. The CBCT images of 5 equine cadaver cheek teeth were segmented with a software 3-dimensional (3D) Slicer using a predefined protocol, corrected manually, and re-assembled into a 3D model. Individual tooth volum...
Auckburally A, Nyman G, Wiklund MK, Straube AK, Perchiazzi G, Beda A, Ley CJ, Lord PF.To develop a method based on CT angiography and the maximum slope model (MSM) to measure regional lung perfusion in anesthetized ponies. Methods: 6 ponies. Methods: Anesthetized ponies were positioned in dorsal recumbency in the CT gantry. Contrast was injected, and the lungs were imaged while ponies were breathing spontaneously and while they were mechanically ventilated. Two observers delineated regions of interest in aerated and atelectatic lung, and perfusion in those regions was calculated with the MSM. Measurements obtained with a computerized method were compared with manual measurement...
Johnston GCA, Ahern BJ, Palmieri C, Young AC.(1) Background: Parasagittal groove (PSG) changes are often present on advanced imaging of racing Thoroughbred fetlocks and have been suggested to indicate increased fracture risk. Currently, there is limited evidence differentiating the imaging appearance of prodromal changes in horses at risk of fracture from horses with normal adaptive modelling in response to galloping. This study aims to investigate imaging and gross PSG findings in racing Thoroughbreds and the comparative utility of different imaging modalities to detect PSG changes. (2) Methods: Cadaver limbs were collected from twenty ...
Hefner EM, Lin HC, Cole RC, Moore PA, McMullen RJ.To compare image quality and acquisition time of corneal and retinal spectral domain optical coherence tomography (SD-OCT) under 3 different sedation-anesthesia conditions in horses. Methods: 6 middle-aged geldings free of ocular disease. Methods: 1 randomly selected eye of each horse was evaluated via SD-OCT under the following 3 conditions: standing sedation without retrobulbar anesthetic block (RB), standing sedation with RB, and general anesthesia with RB. Five regions of interest were evaluated in the cornea (axial and 12, 3, 6, and 9 o'clock positions) and fundus (optic nerve head). Thre...
Baldwin CM, Morgan RE, Crawford AL, Villarino NF, Rubio-Martínez LM.(1) To describe the computed tomography (CT) and gross anatomy of the equine extensor carpi radialis sheath (ECRS) and common digital extensor sheath (CDETS); (2) to describe a single-portal endoscopic examination of the ECRS and CDETS. Methods: Ex vivo experimental. Methods: Thirty clinically normal cadaver thoracic equine limbs severed at the humeral diaphysis. Methods: Ten limbs underwent plain and intrathecal contrast CT examinations and gross dissection of the ECRS and CDETS. Single-portal endoscopic examination of ECRS and CDETS was attempted in 4 limbs and endoscopic examination was per...
Chavatte-Palmer P, Derisoud E, Robles M.Horses have been domesticated by man and historical information mostly associates horses with men. Nowadays, however, horse riding is essentially by women. Women are also very much involved in equine sciences, with a large contribution to the understanding of fetoplacental development. While highlighting the work of female scientists, this review describes the recent advances in equine fetoplacental studies, focusing on data obtained by new generation sequencing and progress on the understanding of the role of placental progesterone metabolites throughout gestation. A second emphasis is made o...
Stewart HL, Kawcak CE, Inscoe CR, Puett C, Lee YZ, Lu J, Zhou OZ, Selberg KT.To describe the technique and assess the diagnostic potential and limitations of tomosynthesis for imaging of the metacarpophalangeal joint (MCPJ) of equine cadavers; compare the tomosynthesis appearance of pathological lesions with their conventional radiographic, CT, and MRI appearances; and evaluate all imaging findings with gross lesions of a given MCPJ. Methods: Distal portions of 4 forelimbs from 4 equine cadavers. Methods: The MCPJs underwent radiography, tomosynthesis (with a purpose-built benchtop unit), CT, and MRI; thereafter, MCPJs were disarticulated and evaluated for the presence...
McQuillan S, Kearney C, Hoey S, Connolly S, Rowan C.Computed tomographic arthrography (CTA) has been described as a method for detecting articular cartilage defects in equine carpal joints; however, published studies on the effects of contrast volume for lesion detection are currently lacking. The purpose of this prospective, experimental, pilot study was to determine a threshold volume of iodinated contrast for CTA of the antebrachiocarpal (ABC) and middle carpal (MC) joints for detection of articular cartilage surface defects. Articular cartilage defects were iatrogenically created in the surfaces of the ABC and MC joints of 20 equine cadaver...
Ehrle A, Lilge S, Clegg PD, Maddox TW.Flexor tendon injuries are a major cause of lameness in performance horses and have considerable impact on equine welfare and the wider horse industry. Ageing and repetitive strain frequently cause varying degrees of tendon micro-damage prior to the recognition of clinical tendinopathy. Whilst B-mode ultrasonography is most commonly utilised for detection and monitoring of tendon lesions at the metacarpal/metatarsal level, the emphasis of recent research has focused on the identification of subclinical tendon damage in order to prevent further tendon injury and improve outcomes. The introducti...
Johnson SA, Biscoe EW, Eilertson KE, Lutter JD, Schneider RK, Roberts GD, Cary JA, Frisbie DD.Elastography is an emerging imaging modality for characterizing tendon injury in horses, but its ability to differentiate tissue deformability relative to treatment group and biochemical properties using a prospective, experimental study design remain unknown. Objectives of the current study were to (a) to investigate differences in glycosaminoglycan, DNA, and soluble collagen levels in mesenchymal stem cell (MSC) treated limbs compared to untreated control limbs utilizing a collagenase model of tendinopathy; (b) compare elastographic features between treatment groups; and (c) determine tissue...
Herteman N, Mosing M, Waldmann AD, Gerber V, Schoster A.Equine asthma (EA) causes airflow impairment, which increases in severity with exercise. Electrical impedance tomography (EIT) is an imaging technique that can detect airflow changes in standing healthy horses during a histamine provocation test. Objective: To explore EIT-calculated flow variables before and after exercise in healthy horses and horses with mild-to-moderate (MEA) and severe equine asthma (SEA). Methods: Nine healthy horses 9 horses diagnosed with MEA and 5 with SEA were prospectively included. Methods: Recordings were performed before and after 15 minutes of lunging. Absolute...
Maśko M, Witkowska-Piłaszewicz O, Jasiński T, Domino M.Infrared thermography is a non-invasive technique which allows to distinguish between pregnant and non-pregnant animals. Detecting accurate body surface temperatures can be challenging due to external factors altering thermograph measurements. This study aimed to determine the associations between the ambient temperature, the hair coat features and the temperatures of mares' abdomens. It compared pregnant and non-pregnant mares throughout 11 months. The research was carried out on 40 Konik Polski mares, which were divided into pregnant and non-pregnant groups. The temperature (Tmax, maximal; ...
Viana GF, Midon M, Fonseca MW, Hataka A, Carandina L, Bueno LMC, Puoli Filho JNP, Machado VMV.In humans and pets, magnetic resonance imaging (MRI) provides important adjunctive anatomic information about the thyroid and its adjacent structures. To the best of our knowledge, however, no studies have been reported regarding the use of MRI for thyroid evaluation in horses. The aim of this study was to obtain qualitative and quantitative parameters of healthy thyroid gland in adult horses by MRI. Eleven horses were submitted to thyroid MRI evaluation. The healthy thyroid of these animals was ensured by normal examinations performed before (free thyroxine and ultrasound) and after (cytology...
Stewart HL, Siewerdsen JH, Nelson BB, Kawcak CE.Access to volumetric imaging modalities, such as magnetic resonance imaging (MRI) and computed tomography (CT), has increased over the past decade and has revolutionised the way clinicians evaluate equine anatomy. More recent advancements have resulted in the development of multiple commercially available cone-beam CT (CBCT) scanners for equine use. CBCT scanners modify the traditional fan-shaped beam of ionising radiation into a three-dimensional pyramidal- or cone-shaped beam of radiation. This modification enables the scanner to acquire sufficient data to create diagnostic images of a regio...
Janczarek I, Kędzierski W, Tkaczyk E, Kaczmarek B, Łuszczyński J, Mucha K.This study aimed to assess the impact of various types of warm-up on the metacarpal and metatarsal surface temperature in jumping sport horses in comparison to leisure horses, which work usually less intensively. Six clinically healthy sport geldings, contestants in showjumping competitions, and six geldings used for leisure riding were included in the study. The experiment was conducted for four consecutive days, during which the horses were warmed up by walking and trotting for various durations. Images were taken with a FLUKE Ti9 thermal imager to determine the resting, post-effort, and rec...
Hartl B, Egerbacher M, Kneissl SM. Detailed radiological evaluation of the normal hyoid apparatus by computed tomography (CT) has not yet been conducted. Thus, it is unclear what type of junction connects the different parts of the equine hyoid apparatus. To describe the normal CT anatomy of the equine hyoid apparatus, and to determine the junction type that connects the different parts of the hyoid apparatus. Combination of retrospective study and prospective cadaver study. The medical records of horses that underwent head CT scans from 2009 to 2018 were retrieved. Inclusion criteria for the CT scans were visibility of at ...
Wagner FC, Reese S, Gerlach K, Böttcher P, Mülling CKW.Long-term cyclic tensile testing with equine palmar/plantar tendons have not yet been performed due to problems in fixing equine tendons securely and loading them cyclically. It is well established that the biomechanical response of tendons varies during cyclic loading over time. The aim of this study was to develop a clamping device that enables repetitive cyclic tensile testing of equine superficial digital flexor tendon for at least 60 loading cycles and for 5 min. Results: A novel cryo-clamp was developed and built. Healthy and collagenase-treated pony SDFTs were mounted in the custom-ma...
Wilson S, Spriet M, Mur PE, Anishchenko S, Beylin D, Katzman S, Galuppo L.Lesions of the deep digital flexor tendon (DDFT) are a cause for foot lameness in horses. Positron emission tomography (PET) could provide valuable information regarding the metabolic activity of these lesions. The aims of this exploratory, prospective, methods comparison study were to assess the ability of fluorine-fluorodeoxyglucose ( F-FDG) PET to detect DDFT lesions and to compare the PET findings with CT and MRI findings. Eight horses with lameness due to pain localized to the front feet were included. Both front limbs of all horses were imaged with F-FDG PET, noncontrast CT, and arteri...
Deacon LJ, Reef VB, Leduc L, de Solis CN.This pictorial essay aims to display the image quality of pocket-sized ultrasound devices and hospital-based equipment to provide clinicians visual information about the potential uses of point-of-care ultrasonography (POCUS) in equine practice. Twenty-two paired images were obtained using traditional ultrasound equipment and pocket-sized ultrasound devices from patients evaluated at veterinary teaching hospitals. Images of many common ultrasound windows and miscellaneous sonographic abnormalities were obtained using pocket-sized ultrasound equipment.
Andersen PH, Broomé S, Rashid M, Lundblad J, Ask K, Li Z, Hernlund E, Rhodin M, Kjellström H.Automated recognition of human facial expressions of pain and emotions is to a certain degree a solved problem, using approaches based on computer vision and machine learning. However, the application of such methods to horses has proven difficult. Major barriers are the lack of sufficiently large, annotated databases for horses and difficulties in obtaining correct classifications of pain because horses are non-verbal. This review describes our work to overcome these barriers, using two different approaches. One involves the use of a manual, but relatively objective, classification system for...
Straticò P, Guerri G, Palozzo A, Di Francesco P, Vignoli M, Varasano V, Petrizzi L.Capsulitis leads to the release of inflammatory mediators in the joint, causing capsular fibrosis and osteoarthritis (OA). Strain elastosonography (SE) measures the elasticity of tissue by evaluating its strain in operator-dependent deformation. The aims of the study were to assess the feasibility, repeatability, and reproducibility of SE for imaging the distal attachment of the joint capsule (DJC) of metacarpophalangeal joints in sound horses (Group S) and in horses with metacarpophalangeal OA (Group P) and to evaluate differences in the elastosonographic patterns of these horses. After a who...
Wagner FC, Gerlach K, Geiger SM, Gittel C, Böttcher P, Mülling CKW.The superficial digital flexor tendon (SDFT) is the most frequently injured structure of the musculoskeletal system in sport horses and a common cause for early retirement. This project's aim was to visualize and measure the strain of the sound, injured, and healing SDFTs in a pony during walk and trot. For this purpose, biplanar high-speed fluoroscopic kinematography (FluoKin), as a high precision X-ray movement analysis tool, was used for the first time in vivo with equine tendons. The strain in the metacarpal region of the sound SDFT was 2.86% during walk and 6.78% during trot. When injured...
Raisis AL, Mosing M, Hosgood GL, Secombe CJ, Adler A, Waldmann AD.Electrical impedance tomography (EIT) provides clinically useful lung images; however, it would be an advantage to extract additional cardiovascular information from the data. The aim of this study was to evaluate if cardiac-related changes measured by EIT can be used to measure pulse rate (PR) under physiological as well as high and low blood pressure states in anaesthetised horses. Electrical impedance tomography data and PR from seven horses anaesthetised in dorsal recumbency were recorded over 1 min during mechanical ventilation and 1 min of apnoea. Data were collected at four measurement ...
van Zadelhoff C, Liuti T, Dixon PM, Reardon RJM.The performance of cone-beam CT (CBCT) systems compared to conventional helical multidetector CT (MDCT) imaging of the equine head is unknown. The aim of this prospective, method-comparison study was to compare the ability of CBCT and MDCT to detect abnormalities in equine cadaver heads. Eleven equine cadaver heads were scanned using a CBCT scanner and a 64-slice MDCT scanner. Consensus evaluations for CBCT and MDCT scans were performed by three observers. Identified abnormalities were grouped into subcategories with a focus on dental abnormalities. Kappa agreement values between detected abno...
Secombe C, Adler A, Hosgood G, Raisis A, Mosing M.Electrical impedance tomography (EIT) generates images of the lungs based on impedance change and was able to detect changes in airflow after histamine challenge in horses. Objective: To confirm that EIT can detect histamine-provoked changes in airflow and subsequent drug-induced bronchodilatation. Novel EIT flow variables were developed and examined for changes in airflow. Methods: Bronchoconstriction was induced using stepwise histamine bronchoprovocation in 17 healthy sedated horses. The EIT variables were recorded at baseline, after saline nebulization (control), at the histamine concentra...
Del Prete C, Freccero F, Lanci A, Hallowell GD, Bullone C, Castagnetti C, Pasolini MP.Ultrasonographic measurement of the vena cava and aorta (Ao) diameters and their ratios have been suggested to be a reliable way of quantifying hypovolemia. To evaluate the feasibility and reliability of an ultrasonographic technique for measurement of Ao and caudal vena cava (CVC) and derived ratios using three different acoustic windows in a population of healthy neonatal foals. Correlation between Ao and CVC measurements and ratios and foals' age or bodyweight were also investigated. In 14 healthy foals aged less than 7 days, the diameters of the Ao and of the CVC in long and short axis we...
De Zani D, Borgonovo S, Biggi M, Vignati S, Scandella M, Lazzaretti S, Modina S, Zani D.Clinical and radiographic investigations of paranasal sinuses in horses are difficult due to the complex anatomy of these regions, the lack of patognomonic symptoms, and the low sensitivity of conventional diagnostic techniques. The aim of this study was to produce an anatomical atlas to support computed tomography (CT) and sinuscopy of the paranasal sinuses of the adult horse. Transverse, sagittal, and dorsal CT images were acquired, and sinuscopy with both rigid and flexible endoscopes was performed. The heads were frozen and sectioned using a band saw, with the cuts aligned as close as poss...
Denoix JM.With progressive advances in ultrasonographic equipment, evaluation of a number of axial skeletal structures is now possible. Ultrasonography is presently the best technique for evaluation of the SSpL and lumbosacral intervertebral discs. It is a useful adjunct to radiography for assessment of spinous processes and AP injuries.
Dixon PM, Barnett TP, Morgan RE, Reardon RJM. Computed tomographic (CT) imaging has allowed new anatomical studies and detailed clinical imaging of the complex, overlapping equine sinonasal structures. Despite the widespread use of CT, no study has specifically identified which compartments are most commonly affected with sinus disorders. CT has also shown the presence of intercurrent, ipsilateral nasal disorders, especially infection of the nasal conchal bullae (NCB) in many cases of sinus disease, but the frequency of intercurrent NCB infections has not been reported. To identify which sinus compartments are most commonly affected in ...
Masko M, Borowska M, Domino M, Jasinski T, Zdrojkowski L, Gajewski Z.The horses' backs are particularly exposed to overload and injuries due to direct contact with the saddle and the influence of e.g. the rider's body weight. The maximal load for a horse's back during riding has been suggested not to exceed 20% of the horses' body weight. The common prevalence of back problems in riding horses prompted the popularization of thermography of the thoracolumbar region. However, the analysis methods of thermographic images used so far do not distinguish loaded horses with body weight varying between 10 and 20%. Results: The superficial body temperature (SBT) of the ...
Barrett MF, Frisbie DD, McIlwraith CW, Werpy NM.While descriptions of the visible soft tissues of the femorotibial joints exist for both arthroscopy and ultrasonography, there are few examples in the literature that discuss in detail the combined findings of these modalities. Objective: To further elucidate the ultrasonographic and arthroscopic boundaries of the normal equine femorotibial joints and improve the understanding of the benefits and limitations of each individual modality. Methods: Simultaneous arthroscopy and ultrasonography were performed in 10 equine cadaver stifles as well as bilateral stifles on a horse that underwent nonre...
Morath U, Luyet C, Spadavecchia C, Stoffel MH, Hatch GM.To develop an ultrasound-guided technique for retrobulbar nerve block in horses, and to compare the distribution of three different volumes of injected contrast medium (CM) (4, 8 and 12 mL), with the hypothesis that successful placement of the needle within the retractor bulbi muscle cone would lead to the most effective dispersal of CM towards the nerves leaving the orbital fissure. Methods: Prospective experimental cadaver study. Methods: Twenty equine cadavers. Methods: Ultrasound-guided retrobulbar injections were performed in 40 cadaver orbits. Ultrasound visualization of needle placement...
Spriet M, Espinosa P, Kyme AZ, Stepanov P, Zavarzin V, Schaeffer S, Katzman SA, Galuppo LD, Beylin D.Positron emission tomography (PET) is a highly sensitive, noninvasive imaging technique for quantifying biological functions of tissues. However, at the time of this study, PET imaging applications had not been reported in the horse. The aim of this exploratory study was to determine whether a portable high-resolution PET scanner could be used to image the equine distal limb. Images of the front feet and fetlocks of three research horses, with known lesions localized to the distal front limbs, were acquired under general anesthesia after administration of 18 F-fluorodeoxyglucose (18 F-FDG), wi...
Hendrickson EH, Malone ED, Sage AM.Six healthy horses were examined by using transabdominal ultrasonography, as described (1-3), to evaluate activity and size of the large colon and cecum at various locations. Using size and number of sacculations, activity patterns and contractile frequency; significant differences that would allow ultrasonographic identification of dorsal versus ventral colons, if they were displaced, were not found. The cecum had significantly greater activity than the colon, and a trend was seen towards smaller sacculations in the cecum than in the large colon. Six chevaux en santé ont été examinés par...
Townsend NB, Hawkes CS, Rex R, Boden LA, Barakzai SZ.Radiography is commonly used for the diagnosis of equine cheek teeth (CT) infection but, to our knowledge, no study to date has evaluated the relative values of individual specific radiographic signs when making a diagnosis. Objective: To investigate the sensitivity and specificity of individual radiographic signs identified from the literature for the diagnosis of CT apical infection using a retrospective case-control study. Methods: Cropped radiographs taken using computed radiography of 41 apically infected CT and 41 control CT were independently blindly evaluated by 3 clinicians for the pr...
Ferrell EA, Gavin PR, Tucker RL, Sellon DC, Hines MT.Magnetic resonance (MR) imaging was used as a neurodiagnostic modality in the assessment of 12 horses with neurologic disease localized cranial to the foramen magnum. This retrospective study included a mixed population of horse breeds and consisted of three foals and nine adult horses. MR sequences of the head and central nervous system of each horse were acquired. Routine MR sequences included transverse T1 weighted (T1wt), T2 weighted (T2wt), and proton density images. Additional imaging sequences were obtained on a patient-dependent basis. Eight neurologic related diseases were diagnosed. ...
Sivaguru M, Eichorst JP, Durgam S, Fried GA, Stewart AA, Stewart MC.Injuries and damage to tendons plague both human and equine athletes. At the site of injuries, various cells congregate to repair and re-structure the collagen. Treatments for collagen injury range from simple procedures such as icing and pharmaceutical treatments to more complex surgeries and the implantation of stem cells. Regardless of the treatment, the level of mechanical stimulation incurred by the recovering tendon is crucial. However, for a given tendon injury, it is not known precisely how much of a load should be applied for an effective recovery. Both too much and too little loading...
Vallance SA, Bell RJ, Spriet M, Kass PH, Puchalski SM.To date, few reports exist comparing magnetic resonance imaging (MRI) and computed tomography (CT) for imaging of the equine distal limb, yet clinicians are required to decide which modality to use regularly. Objective: To report and compare anatomic visualisation scores obtained for CT, contrast enhanced CT (CECT) and standing low-field MRI (LFMRI) in the equine foot. Objective: Anatomic visualisation score discrepancies would exist between CT, CECT and LFMRI. Methods: Images of 22 lame horses (31 limbs) undergoing both CT and LFMRI of the foot were reviewed. When available, CECT images were ...
Spriet M, Buerchler S, Trela JM, Hembrooke TA, Padgett KA, Rick MC, Vidal MA, Galuppo LD.To assess distribution, uptake, and persistence of radiolabeled mesenchymal stem cells (MSC) using scintigraphy after intravenous regional limb perfusion (RLP) and subcutaneous injections in standing, sedated horses. Methods: Experimental study. Methods: Horses (n = 12). Methods: Six horses had RLP performed through the cephalic vein on 1 limb and subcutaneous injection in the metacarpal area in the opposite limb. The other 6 horses had RLP performed through the lateral palmar digital vein and subcutaneous injection in the coronary band. A pneumatic tourniquet was used for the RLP. MSC were la...
Werpy NM, Ho CP, Pease AP, Kawcak CE.Six cadaver forelimbs were imaged in two high-field magnetic resonance (MR) systems and one low-field MR system following the creation of osteochondral defects on the palmar distal aspect of the third metacarpal bone. The following sequences were performed using all three systems: proton density (PD) turbo spin echo, T2* gradient echo (GRE), T2-weighted fast spin echo, and short tau inversion recovery. In addition, 3D T1 GRE sagittal standard and motion insensitive sequences were obtained using the low-field system. PD fat saturated and 3D T1-weighted spoiled GRE images with and without fat su...
Satchell G, McGrath M, Dixon J, Pfau T, Weller R.Infrared imaging is becoming popular as an aid to traditional diagnostic tools, its repeatability under practically relevant conditions is still discussed. Objective: We hypothesise that time of day, ambient temperature and relative humidity affect thermography readings, and that there is no difference between values from left and right side. Methods: Repeated thermography in a convenience sample. Methods: Fifteen sound horses were thermographically imaged at 3 time points in the same day (08.00, 12.00 and 16.00 h). Images were taken of the following regions: neck, carpus, distolateral thora...
Elzer EJ, Wulster KB, Richardson DW, Ortved KF.A 15-year-old Thoroughbred gelding was presented for investigation of fever, right temporomandibular region swelling, and progressive pain when opening the mouth. Right temporomandibular joint (TMJ) sepsis was diagnosed based on synovial fluid analysis, sonographic imaging, and standing robotic cone-beam computed tomography. Concurrent otitis media and temporohyoid osteoarthropathy (THO) were also noted. The horse was treated with arthroscopic debridement and lavage during standing sedation followed by local and systemic antimicrobial therapy. There were no complications associated with the su...
Latorre R, Arencibia A, Gil F, Rivero M, Henry RW, Ramírez G, Váquez JM.To correlate anatomic features of the equine tarsus identified in plastinated sections with images obtained via magnetic resonance imaging (MRI). Methods: 4 horses. Methods: MRI (1.5-Tesla magnet) of the tarsus was performed on the pelvic limbs of 4 clinically normal horses following euthanasia. After imaging, tarsocrural joint spaces and vasculature were injected with colored latex. Sagittal and transverse sections of the tarsi were plastinated to facilitate interpretation of MR images. Results: Relevant anatomic structures were identified and labeled on the plastinated tissue slices and corr...
Wang X, Thomas CD, Clement JG, Das R, Davies H, Fernandez JW.In this study, the development of a mechanostatistical model of three-dimensional cortical bone remodelling informed with in vivo equine data is presented. The equine model was chosen as it is highly translational to the human condition due to similar Haversian systems, availability of in vivo bone strain and biomarker data, and furthermore, equine models are recommended by the US Federal Drugs Administration for comparative joint research. The model was derived from micro-computed tomography imaged specimens taken from the equine third metacarpal bone, and the Frost-based 'mechanostat' was in...
Dietze K, Slosarek I, Fuhrmann-Selter T, Hopperdietzel C, Plendl J, Kaessmeyer S.Arterial or venous thromboses are frequent clinical complications with the risk of fatal progression. Recent studies suggest the disruption of angiogenesis in the course of thrombus resolution as the underlying pathomechanism. Very similar to the situation in human patients, equine vessels have been described to be particularly susceptible to thrombosis. In contrast to humans, equine donors are readily available to obtain organs and tissues for isolation of endothelial cells. Objective of this study was to isolate equine endothelial cells and develop an angiogenesis assay from primary cultures...
Brooks KE, Daughtry BL, Metcalf E, Masterson K, Battaglia D, Gao L, Park B, Chavez SL.The timing of early mitotic events during preimplantation embryo development is important for subsequent embryogenesis in many mammalian species, including mouse and human, but, to date, no study has closely examined mitotic timing in equine embryos from oocytes obtained by ovum pick-up. Here, cumulus-oocyte complexes were collected by transvaginal follicular aspiration, matured invitro and fertilised via intracytoplasmic sperm injection. Each fertilised oocyte was cultured up to the blastocyst stage and monitored by time-lapse imaging for the measurement of cell cycle intervals and identifica...
Withers JM, Voûte LC, Hammond G, Lischer CJ.Plain radiography is the standard imaging technique for investigation of diseases associated with the articular process joints (APJ) of the caudal neck; however, the radiographic anatomy of these structures on both lateral and oblique radiographic projections has not previously been described in detail. Objective: To determine the optimal technique for obtaining oblique radiographs of the APJ of the caudal cervical vertebrae (C4-5, C5-6 and C6-7) and to provide a detailed description of their normal radiographic appearance, on both lateral and oblique radiographic projections. Methods: Radiopa...
Lu Z, Kasaragod DK, Matcher SJ.We describe a fibre-based variable-incidence angle (VIA) polarization-sensitive swept-source optical coherence tomography (PS-SS-OCT) system to determine the 3D optical axis of birefringent biological tissues. Single-plane VIA-PS-OCT is also explored which requires measurement of the absolute fast-axis orientation. A state-of-the-art PS-SS-OCT system with some improvements both in hardware and software was used to determine the apparent optical birefringence of equine tendon for a number of different illumination directions. Polar and azimuthal angles of cut equine tendon were produced by the ...
Arble JB, Mattoon JS, Drost WT, Weisbrode SE, Wassenaar PA, Pan X, Hunt RJ, Belknap JK.Equine laminitis is a severely debilitating disease. There is a poor understanding of the underlying pathophysiology, and traditional imaging modalities have limited diagnostic capacity. High field strength magnetic resonance (MR) imaging allows direct visualization of the laminae, which other modalities do not. This would prove useful both in assessment of clinical patients and in further investigation into the pathophysiology of the disease. The objective of this study was to characterize the anatomic changes within the equine foot associated with the initial active stage of laminitis. Image...
Scrivani PV, Levine JM, Holmes NL, Furr M, Divers TJ, Cohen ND.Different examiners or the same examiner were observed at different times producing slightly different results when obtaining cervical-vertebral ratios. If the difference is substantial, then measurement variability would have an important impact of radiographic interpretation. Objective: To quantify agreement and repeatability of these measurements. Methods: An observer agreement study was performed using 75 horses. Measurements were made at C3-4 and C6-7 by a board-certified radiologist and an imaging resident. Intra- and interobserver agreement was quantified using Bland-Altman plots. Repea...
Domino M, Romaszewski M, Jasiński T, Maśko M.Infrared thermography (IRT) is a valuable diagnostic tool in equine veterinary medicine; however, little is known about its application to donkeys. This study aims to find patterns in thermal images of donkeys and horses and determine if these patterns share similarities. The study is carried out on 18 donkeys and 16 horses. All equids undergo thermal imaging with an infrared camera and measurement of the skin thickness and hair coat length. On the class maps of each thermal image, fifteen regions of interest (ROIs) are annotated and then combined into 10 groups of ROIs (GORs). The existence o...
Berg LC, Nielsen JV, Thoefner MB, Thomsen PD.In equine patients, the cause of clinical signs possibly related to the cervical region is often difficult to diagnose. Ultrasonography allows quick and noninvasive visualisation, but reference material of the normal equine neck is needed. Objective: To describe and document the normal ultrasonographic appearance of transverse scans in the cervical region with emphasis on the synovial articular facet joints, cervical vertebrae and paravertebral structures; and further, to provide images of frozen cross-sections for anatomical reference. Methods: A study describing the normal ultrasonographic a...
Martinelli MJ, Kuriashkin IV, Carragher BO, Clarkson RB, Baker GJ.Magnetic resonance imaging was used to examine the equine metacarpophalangeal joint. Thirty-two saggital images generated by partial volume imaging were transferred to a computer for three-dimensional reconstruction and analysis. All the tissues constituting the metacarpophalangeal joint were readily identified. The most significant increase finding regarded the soft tissues on the palmar aspect of the metacarpophalangeal joint and their interactions with the proximal sesamoid bones. The equine metacarpophalangeal joint has not previously been evaluated using 3-dimensional imaging software.
Arencibia A, Vazquez JM, Ramirez JA, Ramirez G, Vilar JM, Rivero MA, Alayon S, Gil F.The purpose of this investigation was to define the magnetic resonance (MR) imaging appearance of the brain and associated structures of the equine head. MR images were acquired in oblique dorsal (T2-weighted), sagittal (T1-weighted), and transverse planes (T2-weighted), using a magnet of 1.5 Tesla and a human body coil. Relevant anatomic structures were identified and labeled at each level. The resulting images provided excellent anatomic detail of the cranioencephalic structures. Annotated MR images from this study are intended as a reference for clinical imaging studies of the equine head, ...
Epperly E, Whitty JA.Computed tomography (CT) has revolutionized the veterinarian's ability to image the equine skull and led to improved diagnostic accuracy and clarity for surgical planning. The increased cost for this evaluation is offset by more accurate diagnosis and targeted therapy. As novel technology is developed that allows for increased availability of equine head, the price will continue to decrease and more examinations will be performed. New skills are needed for the veterinarian to accurately interpret this modality. This article reviews the normal CT appearance of the equine skull and presents exam...
