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.
Yoxall AT.The principles of radiological protection are summarised and consideration is then given to problems, which may confront the equine practitioner, in the fulfillment of these principles during diagnostic radiography of the limbs, head, and spine of the horse. The place of anaesthesia in such procedures is discussed and the special problems associated with therapeutic radiography of the horse are considered.
Brown MP, MacCallum FJ.Tetracycline-labeled bones of 23 foals from 52 to 104 days old were sectioned and macroscopically examined to assess the extent of ossification or fusion of ossification centers. A grading system was devised with which to record information about the ossification centers and growth plates. The objective was to define anatomic standards which could contribute toward obtaining an accurate radiologic interpretation. Labeled limb bones of 3 neonatal foals were similarly treated, but grading of these was limited to the consideration of whether each site was still cartilaginous or had commenced to o...
Chapple AR, Daglish J, Stover SM, Slipchenko N, Phillips KL.Stress fracture is an important cause of mortality and morbidity in racing Thoroughbreds. Nuclear scintigraphy is the imaging modality of choice for investigating unlocalised stress-related bone remodelling in horses. Stress fractures of the caudal lumbar vertebral column have been previously described in both racing Quarter horses and racing Thoroughbreds post-mortem. There is a lack of literature describing the imaging appearance of vertebral stress fractures in racehorses ante-mortem. Objective: To describe: (1) ante-mortem scintigraphic appearance of presumed thoracolumbar vertebral stress...
Honnas DH, Fiske-Jackson AR, Fulkerson CV, Wilhite DR.An injury of a tendon or ligament of the equine foot is frequently a cause of lameness. The optimal radiographic projections delineating the entheses of five commonly injured tendons and ligaments of the foot should be described. Methods: The entheses of the collateral ligaments of the distal interphalangeal joint, the collateral sesamoidean ligaments of the navicular bone, the deep digital flexor tendon, the common digital extensor tendon and the distal sesamoidean impar ligament were isolated from a thoracic foot of three cadavers. Three standard radiographic projections (60-degree, dorsopro...
Frey K, Perlini M, Reed R.Intravenous (IV) contrast administration during computed tomography (CT) of the equine head is routinely performed to delineate the extent of disease and differentiate between vascular and nonvascular tissue. Current equine scan protocols are extrapolated from human and canine studies. There have been no prospective equine studies describing the optimal time to image the patient after administration of contrast or the optimal site of contrast administration. Therefore, the current postcontrast times to scan and sites of contrast administration may not be appropriate for use in horses. The obje...
Malekipour F, Whitton RC, Muir P, Lee PV.Stress fractures are common in racehorses, with the metacarpophalangeal (MCP) joint being the most frequently affected site as it is subjected to high-magnitude and high-rate cyclic loads during training and racing. These loads lead to repeated compressive stresses, resulting in subchondral bone (SCB) sclerosis, fatigue microcracks, and matrix damage that can progress to parasagittal fractures or palmar osteochondral disease (POD). The present study developed joint-specific 3D FE models and slice-based FE models using standing CT images for three trained racehorses, each presenting distinct SC...
Sellke L, Ludewig E, Handschuh S, Witter K.In a previous study on hoof biometry, we found that mathematical correction of measuring results from radiographs did not lead to complete correspondence to computed tomography (CT) results. The present study investigates this finding by comparing 13 measures of six cadaveric equine digits collected with the following workflows: radiographs with 1 and 2 m focus-object distance (FOD) (Xray 1 m/2 m), computed tomography images in planes defined based on anatomical landmarks (CTw), simulated radiographs based on the tomography dataset (virtual 120-mm slabs, Xray Sim) and measurements based ...
Ellero N, Maggi A, Busoni V, Imposimato I, Castagnetti C, Lanci A, Mariella J, Freccero F.This study aimed to develop a standardized ultrasound (US) protocol using selected thoracic and abdominal acoustic windows, to assess its feasibility and applicability in healthy foals, and to evaluate its usefulness for detecting common thoracic and abdominal conditions in sick foals. The Focused US (FUS) protocol included 12 thoraco-abdominal windows (4 right-side, 3 ventral, 5 left-side) using a curved-array probe. It was applied to cohorts of healthy (n = 17) and sick (n = 23) foals by a veterinary clinician with limited US experience. The FUS showed good feasibility and applicabil...
Key K, Berg K, Kirkegaard J, Andresen KR, Hansen SS.Equine lameness diagnosis largely relies on subjective visual assessments, which can be biased. Although marker-based methods, force plates and inertial measurement units (IMUs) provide objective measurements, they require specialized setups. Vision-based algorithms offer a portable, markerless alternative, but their accuracy needs thorough testing. Objective: To evaluate a custom vision-based algorithm for estimating the groundline across multiple camera angles, including handheld use in horses trotting on a treadmill. Methods: Experimental comparative study. Methods: Eight Standardbred trott...
Hansen T, Kendall A, Finne R, Law E, Ringdahl A, Nostell K.Abdominal ultrasound is widely used to evaluate the intestinal tract of horses. Despite being a routine examination, there is limited data on the reliability of this diagnostic procedure. Objective: To investigate intra- and inter-rater reliability of ultrasonographic intestinal wall thickness measurements in healthy horses. A second aim was to assess variance within repeated measurements to determine threshold values that distinguish whether differences between repeated examinations are true findings versus solely due to measurement variation. Methods: In vivo reliability study. Methods: Eigh...
de Chaisemartin C, Belluco S, Nottrott K.Dental masses such as odontogenic masses, heterotopic polydontia, or ectopic supernumerary teeth have been documented in the equine head. This is the first case report of a large maxillary sinus mass with 3 ectopic teeth in an adult horse. A 14-year-old warmblood gelding was presented for evaluation of chronic right-sided nasal discharge. After imaging exploration, surgery was performed on the standing horse with a conchofrontal sinus trephination and a large maxillary bone (MB) sinusotomy. The examinations revealed a sinusal mass in the right maxillary sinus covered by sinusal mucosa and surr...
Lemercier J, Pasco J, Olivier G, Amiot F.Horse riding-related falls are a frequent cause of emergency department (ED) presentations; however, their regional epidemiology in France is poorly described. We aimed to quantify the incidence of ED visits after falling from a horse in the Manche Department and characterize the injury patterns, resource use, and short-term outcomes. Methods: We conducted a multicenter retrospective study across six hospitals in Manche (France), including all patients presenting to the ED after a fall from a horse between May 1, 2021, and October 31, 2024. Demographics, initial clinical status, imaging findin...
Aliani C, Lorenzetto Bologna C, Francia P, Bocchi L.Standing equine computed tomography (CT) acquisitions are susceptible to residual postural sway, which can introduce view-inconsistent motion and degrade image quality. External optical tracking based on ChArUco fiducials is a promising, low-cost strategy to enable projection-wise motion compensation, yet quantitative guidance on how camera-marker geometry affects pose-estimation performance remains limited. This CT-motivated benchtop study characterizes how the relative camera-ChArUco configuration influences both the accuracy (bias with respect to ground truth) and the precision (repeatabili...
DeClue A, Workman K, May-Davis S.To date, radiographically identifying the bony landmarks relevant to diagnosing the complete C6 aplasia of the caudal lamina ventralis (C6 aCLV4) has not been described. Furthermore, a gross study has identified C6 aCLV4 as the main correlation between transposition of the CLV from C6 to C7, where coinciding neck pain was commonly reported. This study aimed to identify C6 aCLV4 in radiographs, where the outcome might benefit equine practitioners in isolating neck pain. Initially, the relevant bony landmarks were radiographically determined from a normal C6 by applying a lateral 30° dorsal-ven...
Haussler KK.Congenital cervical vertebral anomalies in horses are structural changes in the neck vertebrae that develop during the fetal stage. These anomalies can vary in their severity and effects. Some horses may not show any clinical signs and can live normally, while others may develop serious problems such as spinal cord compression. This compression can lead to issues like ataxia or even paralysis, affecting the horse's mobility and quality of life. Recognizing and diagnosing these anomalies early are very important, as it helps guide decisions about the best treatment options and overall managemen...
Ferrara MA, Preziosi G, Boni R, Ruggiero R, Gualandi SC.This study employs Holographic tomography (HT) to examine structural and biophysical changes occurring during the cryopreservation of stallion sperm. HT is an advanced imaging technique that integrates digital holography with tomography to achieve three-dimensional, quantitative reconstructions of objects without the need for treatment or reporter dyes. By using refractive index (RI) intervals to represent specific structural regions of sperm cells, variations in optical density, surface area, volume, and dry mass across different cryopreservation extenders and donors have been quantified. Thr...
Webster AP, Wright RK, Hammond JB, Kotey NA, Gleason CB, White RR.This study explored whether thermal imaging could provide an objective means of body condition scoring (BCS) horses and multiparous, gestating beef cows. This study consisted of two parts: one part assessed BCS in horses of the Quarter Horse or Thoroughbred breed types while the other evaluated BCS of gestating beef cows. Ground truth BCS were assigned by five to eight trained scorers for each animal. Thermal images were also collected from one or both sides of the body and analyzed for surface temperature. Surface temperature and BCS were evaluated with the whole body, and for five (cows) or ...
Woods T, Dixon J, Melvaine C, Fraser B.To determine the ideal location of a medial tenoscopic portal in the equine carpal flexor tendon sheath (CFTS) using contrast computed tomography (CT). Methods: Experimental cadaver study. Methods: A total of 20 entire forelimbs from adult Standardbred horses. Methods: Contrast media diluted in saline was injected into the CFTS from a lateral approach before manually flexing and extending the limb 20 times to disperse the contrast solution. The limbs were placed in lateral recumbency and a capped 21-gauge 1.5 inch needle was placed approximately 5 mm proximal and 32 mm caudal to the palpab...
Laundon D, Proudley E, Basford PJ, Katsamenis OL, Chatelet DS, Cleal JK, Gostling NJ, Chavatte-Palmer P, Lewis RM.Placental structure is linked to function across morphological scales. In the placenta, changes to gross anatomy, such as surface area, volume, or blood vessel arrangement, are associated with suboptimal physiological outcomes. However, quantifying each of these metrics requires different laborious semi-quantitative methods. Here, we demonstrate how, with minimal sample preparation, whole-organ computed microtomography (microCT) can be used to calculate gross morphometry of the equine placenta and a range of additional metrics, including branching morphometry of placental vasculature, non-dest...
de Souza LWG, Oliveira EA, Vieira JW, Farias WAWA, de Souza Santos W, Neves LP, Perini AP.Portable X-ray equipments are commonly used in diagnostic radiology of equine patients. Despite its benefits, the exposure to ionizing radiation can pose a health risk to workers as physical restraint of patients is typically required. In this context, the aim of this study was to apply Monte Carlo simulation to investigate occupational exposure in the diagnosis of horses. The simulations were carried out by the Monte Carlo N-Particle 6.2 (MCNP6.2) code. The workers were represented by a FASH3 (female) and MASH3 (male) virtual anthropomorphic phantoms. To simulate the horse, a realistic virtua...
Maier J, Rosenstand MG, Thim P, Aalund M.Introduction Imaging experience made us suspect an overrepresentation of ponytails in riders admitted as polytrauma after falling from their horse. Methods In a single-centre case-control study conducted over three months, we reviewed the records of all admitted polytraumatised patients for trauma mechanism and presence of ponytail on CT. Cerebral CTs were reviewed in the three standard imaging planes using a bone or lung window. Ponytail was diagnosed if most or all of the hair on the head was gathered and secured at the back of the head with a hair tie. Data were analysed with Fisher's exact...
Dufourni A, Demeyere M, Vera L, van Loon G, Decloedt A.This study aimed to compare two-dimensional, M-mode, color, pulsed-wave Doppler (PWD) and continuous-wave Doppler (CWD) echocardiography, and PWD ultrasonography of the caudal common carotid artery (CCA) in horses with aortic regurgitation (AR). Methods: Warmblood horses without (n = 20) and with mild, moderate, and severe AR (n = 60) were included in the study. Methods: A retrospective descriptive study focused on cardiac dimensions, aortic and CCA Doppler flow. Non-invasive blood pressure and presence of ventricular arrhythmia were recorded. Groups were compared using analysis of varianc...
Trostle SS, Kearney EM, Medoff M, Devaney S.To describe the clinical presentation, diagnosis, and treatment of a fragmented, migrating acupuncture needle near the palmar proximal interphalangeal joint (PIPJ) of a horse. Methods: A 9-year-old Warmblood cross mare. Unassigned: The mare presented for evaluation of a linear metallic foreign body on the palmar lateral aspect of the PIPJ following acupuncture treatment. The mare had a pinpoint puncture wound and sensitivity to palpation over the lateral aspect of the PIPJ region. The referring veterinarian performed radiographs and found a linear metallic foreign body near the lateral palmar ...
Iwasaki N, Llewellyn J, Brown J, Zamboulis DE, Finding EJT, Wheeler-Jones CPD, Thorpe CT.Tendon degeneration is common, and its risk increases with age both in humans and horses. Tendon regeneration and healing is limited due to inherent low cell density and vascularisation, and current treatments are insufficient as indicated by scar tissue formation and a high re-injury rate. The tendon vasculature plays a crucial role in tendon homeostasis, regeneration and healing, making it a potential therapeutic target. However, the effect of ageing on the tendon microvasculature is poorly understood. Here, we provide the first comprehensive characterisation of the tendon microvasculature. ...
Leduc L, Underwood C, Stefanovski D, Hurcombe S, Navas de Solis C.To assess whether remote assistance is beneficial to the accuracy of point-of-care ultrasound (POCUS) examinations during equine emergency evaluations. Methods: Adult horses presenting to a tertiary care large animal emergency service for respiratory or gastrointestinal clinical signs. Methods: Prospective, randomized, controlled, clinical study. Cases were assigned to receive POCUS with remote assistance ("POCUS-R" group) or POCUS with no assistance ("POCUS" group). Accuracy of diagnosis, duration of sonograms and survival to discharge were the objective outcomes compared between groups. Perc...
Freccero F, Padalino B, Carstens A, Raidal SL.Point of care ultrasonographic (POCUS) assessment of the equine abdomen is now readily available to the equine practitioner using hand-held ultrasound transducers. Commonly used medications may alter the sonographic appearance or function of the small intestine, caecum or colon. Objective: To demonstrate qualitative and quantitative effects of xylazine sedation on intestinal motility of healthy horses using hand-held, wi-fi ultrasound transducers and validate POCUS methodology by determination of intra- and interobserver agreement. Methods: Double-blind cross-over study of eight healthy horses...
Boozarjomehri Amnieh S, Ropka-Molik K.The horse is a distinctive translational model for bridging mechanistic discovery and clinically relevant investigation because of its physiological complexity, long lifespan, athletic phenotype, and broad spectrum of naturally occurring conditions that parallel aspects of human health and disease. Its utility extends from musculoskeletal and joint research to immunology, metabolic disorders, and exercise physiology, particularly where naturally developed disease, clinically applicable imaging, and longitudinal sampling are required. Additionally, it offers opportunities to examine both chroni...
Jasiński T, Borowska M, Juszczuk-Kubiak E, Turek B, Kaczorowski M, Bąk M, Żuk J, Domino M.Horses presenting with temporomandibular joint (TMJ) dysfunctions are often clinically evaluated for TMJ osteoarthritis (OA). Due to the unique characteristic of TMJ-related pain, the clinical diagnosis of equine TMJ OA is challenging; however, it may be supported by computer-aided tools incorporating biomarker data. This study aims to evaluate a machine learning-based approach to address a binary classification distinguishing healthy TMJs from TMJ OA. Among 50 equine cadaver heads, 82 TMJs were included and annotated as healthy or OA based on histological and computed tomography (CT) findings...
Pye E, Marcilla MG, Duncan JC.Regional anaesthesia of the equine anogenital tract is limited to local infiltration, extradural, blind palpation and nerve stimulator-guided techniques which risk iatrogenic damage, recumbency and ataxia. This study aimed to describe and assess the feasibility of transcutaneous ultrasound-guided (USG) pudendal nerve staining in equine cadavers. An initial pilot phase used two fresh equine cadavers and one standing unsedated horse to image the intrapelvic anatomy using ultrasound. One fixed equine cadaver specimen was also dissected to identify the pudendal nerve and refine the dissection appr...
Putnoki V, Pollard D, Dyson S, Boros K, Nagy A.There are limited data on sequential computed tomographic (CT) evaluation and objective CT assessment of the metacarpal condyles in Thoroughbred racehorses. This longitudinal study aimed to document changes in attenuation of the metacarpal condyles during the first two years of training and racing. Fan-beam CT examination of the metacarpophalangeal regions was performed on 40 non-lame Thoroughbred yearlings, and repeated four more times, approximately six months apart. Mean Hounsfield Unit (HU) measurements were obtained on sagittal reconstructions of the dorsal and palmar halves of the medial...
Luedke LK.This article provides an overview of equine paranasal sinus disease with emphasis on relevant anatomy, diagnostic considerations, and commonly encountered pathologic conditions. It outlines the structure and drainage of the paranasal sinuses to establish a foundation for understanding disease development and spread. The discussion reviews available diagnostic modalities and their roles in localizing disease and determining underlying causes. Common sinus disorders are presented with attention to their general pathophysiology, diagnostic features, treatment approaches, and expected outcomes. Co...
Manso-Díaz G.Diagnostic imaging is essential for evaluating and managing neurologic disease in horses. Following clinical lesion, neurolocalization imaging modalities are often necessary to further characterize the disease process. However, which technology to use depends on various factors, including the patient's size, clinical signs, and the anatomic region. Current advances in imaging technology, in general, and the adaptation of different modalities for equine patients, in particular, have substantially improved our ability to evaluate the equine central nervous system. This article will summarize the...
