Topic:Computed Tomography
Computed Tomography (CT) in horses is an advanced imaging technique used to obtain detailed cross-sectional images of equine anatomy. This non-invasive method utilizes X-ray technology combined with computer processing to create detailed images of bones, soft tissues, and other internal structures. CT is particularly useful for diagnosing complex conditions in the head, neck, and limbs of horses, offering enhanced visualization compared to traditional radiography. The technique is valuable for identifying fractures, dental issues, sinus diseases, and other abnormalities. This page compiles peer-reviewed research studies and scholarly articles that explore the applications, advancements, and clinical implications of computed tomography in equine medicine.
Transoesophageal ultrasound and computer tomographic assessment of the equine cricoarytenoid dorsalis muscle: Relationship between muscle geometry and exercising laryngeal function. Early detection of recurrent laryngeal neuropathy (RLN) is of considerable interest to the equine industry. Objective: To describe two imaging modalities, transoesophageal ultrasound (TEU) and computed tomography (CT) with multiplanar reconstruction to assess laryngeal muscle geometry, and determine the relationship between cricoarytenoid dorsalis (CAD) geometry and function. Methods: Two-phase study evaluating CAD geometry in experimental horses and horses with naturally occurring RLN. Methods: Equine CAD muscle volume was determined from CT scan sets using volumetric reconstruction with Live...
Qualitative assessment of bone density at the distal articulating surface of the third metacarpal in Thoroughbred racehorses with and without condylar fracture. Changes in subchondral bone density, induced by the repetitive cyclical loading of exercise, may potentiate fatigue damage and the risk of fracture. Objective: To use computed tomography (CT) to characterise bone density patterns at the articular surface of the third metacarpal bone in racehorses with and without lateral condylar fractures. Methods: Case control METHODS: Computed tomographic images of the distal articulating surface of the third metacarpal bone were obtained from Thoroughbred racehorses subjected to euthanasia in the UK. Third metacarpal bones were divided into 3 groups based ...
COMPUTED TOMOGRAPHIC APPEARANCE OF MELANOMAS IN THE EQUINE HEAD: 13 CASES. Melanomas are one of the most common neoplasms in the horse and are frequently found in the head region. There is a genetic predisposition in horses with a gray hair coat. Computed tomography (CT) is frequently used in referral practice to evaluate the equine head but there are few reports describing the CT appearance of melanomas in this location. The aim of this retrospective, case series study was to describe characteristics in a group of horses with confirmed disease. Case records from two referral hospitals were reviewed, and 13 horses were identified that had undergone CT of the head, wi...
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. 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. To compare the established technique of CT in the depiction of the equine nasal cavities, paranasal sinuses and adjoining anatomical structures to 3 Tesla MRI the nasal cavities and paranasal sinuses of 13 horses were examined using CT and 3 Tesla MRI. Results: Comparison of CT and MRI ima...
Computed Tomographic Appearance of the Temporomandibular Joint in 1018 Asymptomatic Horses: A Multi-Institution Study. Published descriptions of nonseptic arthritis of the equine temporomandibular joint (TMJ) are rare and large studies investigating variations in the TMJ for asymptomatic horses are lacking. The objectives of this cross-sectional, retrospective, multi-institutional study were to describe anatomical variations in the TMJ detected using computed tomography (CT) in an equid population asymptomatic for TMJ disease and determine whether these variations were associated with patient signalment, reason for CT examination, or CT slice width. Medical records at eight hospitals were searched for horses t...
Intra-arterial versus intra venous contrast-enhanced computed tomography of the equine head. The anatomical complexity of the horse's head limits the abilities of radiography. Computed tomography (CT) in combination with contrast enhanced CT is used more often for diagnosing various head pathology in horses. The objective of this study was to compare intravenous and intra-arterial contrast-enhancement techniques and describe normal and abnormal contrast enhancement in the horse's head. Results: All 24 horses included in the study recovered without complication from the procedures. Compared to the pre-contrast studies, post-contrast studies showed significant contrast enhancement in th...
Diagnostic Imaging of the Lower Respiratory Tract in Neonatal Foals: Radiography and Computed Tomography. Diagnostic imaging plays an essential role in the diagnosis and monitoring of lower respiratory disease in neonatal foals. Radiography is most widely available to equine practitioners and is the primary modality that has been used for the characterization of respiratory disease in foals. Computed tomography imaging, although still limited in availability to the general practitioner, offers advantages over radiography and has been used diagnostically in neonatal foals with respiratory disease. Recognition of appropriate imaging protocols and patient-associated artifacts is critical for accurate...
An anatomical study of the dorsal and ventral nasal conchal bullae in normal horses: Computed tomographic anatomical and morphometric findings. Infection of the dorsal nasal conchal bulla and ventral nasal conchal bulla has recently been shown to cause clinical disease in horses, but the anatomy of these 2 structures is poorly documented. Objective: To describe the anatomical features, dimensions and relationships to adjacent structures of the dorsal conchal bulla and ventra conchal bulla in normal horses using computed tomography (CT). Methods: Descriptive imaging study using cadavers. Methods: Computed tomographic images acquired from 60 equine cadaver heads that were shown to be free of sinonasal disease were categorised into 3 age...
Radiographic, computed tomographic and surgical anatomy of the equine sphenopalatine sinus in normal and diseased horses. Knowledge of imaging anatomy, surgical anatomy and disorders affecting the sphenopalatine sinus are currently lacking. Objective: To describe the computed tomographic (CT) and surgical anatomy of the sphenopalatine sinus and diagnosis, treatment and outcome in clinical cases with sphenopalatine sinus disease. Methods: Cadaver observational study and retrospective case series. Methods: The sphenopalatine sinuses of 10 normal cadaver heads were examined with digital radiography, CT and sinoscopic examination prior to anatomical sectioning. Sphenopalatine sinus anatomy was described and compared ...
Seizures in horses: diagnosis and classification. Seizures are a diverse and very common set of chronic neurologic disorders in humans and dogs but are less common in horses. Seizures refer to a specific clinical event (described as sudden and severe) regardless of the etiology, which includes both intracranial and extracranial causes. Therefore, after briefly reviewing some definitions, this article aims to describe the use of a standardized classification, which could facilitate a logical approach for the clinician to establish a diagnosis, as well as to use a consistent mode of communication. For instance, seizures can be classified by typ...
Locking Compression Plate Fixation of Equine Tarsal Subluxations. To report the clinical findings and outcome of locking compression plate (LCP) fixation of tarsal subluxations in horses. Methods: Retrospective case series. Methods: Horses (n = 3) and ponies (2). Methods: All horses and ponies diagnosed with tarsal subluxations and treated with LCP fixation at our institution between 2011 and 2013 were included. Data were collected from the medical records, including all radiographic and computed tomographic (CT) studies and reviewed. Long-term (>1 year) followup examination, including owner interview, and clinical and radiographic examinations were perfo...
Central tarsal bone fractures in horses not used for racing: Computed tomographic configuration and long-term outcome of lag screw fixation. There are no reports on the configuration of equine central tarsal bone fractures based on cross-sectional imaging and clinical and radiographic long-term outcome after internal fixation. Objective: To report clinical, radiographic and computed tomographic findings of equine central tarsal bone fractures and to evaluate the long-term outcome of internal fixation. Methods: Retrospective case series. Methods: All horses diagnosed with a central tarsal bone fracture at our institution in 2009-2013 were included. Computed tomography and internal fixation using lag screw technique was performed in ...
Imaging Diagnosis – Use of Multiphase Computed Tomographic Urography in the Diagnosis of Ureteral Tear in a 6-Day-Old Foal. A 6-day-old foal was evaluated for depression and inappetence. After initial stabilization, the filly developed a hypochloremic metabolic alkalosis and persistent hypercreatinemia. Abdominal ultrasound revealed fluid accumulation around the left kidney and a well-defined rounded fluid filled structure dorsal to the urinary bladder. Computed tomography revealed a partial tear of the left ureter with distension of the retroperitoneal membrane. Exploratory celiotomy was performed to allow left kidney nephrectomy. At 6 months follow-up, the filly was growing normally without complications. Ultraso...
Radiographic and Computed Tomographic Configuration of Incomplete Proximal Fractures of the Proximal Phalanx in Horses Not Used for Racing. To characterize the configuration of incomplete proximal fractures of the proximal phalanx (P1) in horses not used for racing and compare radiographic with computed tomography (CT) findings. Methods: Historical cohort. Methods: Twenty-four horses with incomplete fractures of P1. Methods: Medical records of horses not used for racing diagnosed with an incomplete proximal fracture of P1 based on clinical and radiographic examination and confirmed by CT between 2008 and 2013 were retrieved. Radiographs and CT studies of these horses were analyzed using a subjective grading system and by measuring...
Cervical Vertebral Lesions in Equine Stenotic Myelopathy. Skeletal lesions in the articular processes of cervical vertebrae C2 to C7 were compared between Thoroughbred horses with cervical stenotic myelopathy (17 males, 2 females; age, 6-50 months) and controls (6 males, 3 females; age, 9-67 months). Lesions identified by magnetic resonance imaging occurred with an increased frequency and severity in diseased horses and were not limited to sites of spinal cord compression. Lesions involved both the articular cartilage and trabecular bone and were further characterized using micro-computed tomography and histopathology. The most common histologic lesi...
Biomechanical modelling of impact-related fracture characteristics and injury patterns of the cervical spine associated with riding accidents. Horse-related injuries are manifold and can involve the upper and lower limbs, the trunk, spine or head. Cervical spine injuries are not among the most common injuries. However, they can be fatal and often result in neurological symptoms. This study investigated the influence of the posture of the cervical spine on the ultimate strength and the pattern of vertebrae failure with the aim to provide some guidance for protective clothing design. Methods: Eighteen human cervical spines, each divided into two specimens (three vertebrae each), were subjected to a simulator test designed to mimic a sp...
Computed Tomographic Tenography of Normal Equine Digital Flexor Tendon Sheath: An Ex Vivo Study. Aim of this study was to document the normal computed tomographic tenography findings of digital flexor tendon sheath. Six ex vivo normal equine forelimbs were used. An axial approach was used to inject 185 mg/mL of iopamidol in a total volume of 60 mL into the digital flexor tendon sheaths. Single-slice helical scans, with 5 mm thickness, spaced every 3 mm, for a pitch of 0.6, and with bone algorithm reconstruction, were performed before and after injections of contrast medium. To obtain better image quality for multiplanar reconstruction and 3D reformatting, postprocessing retrorecon...
Osteopathology in the Equine Distal Phalanx Associated With the Development and Progression of Laminitis. Although the equine distal phalanx and hoof lamellae are biomechanically and physiologically integrated, bony changes in the distal phalanx are poorly described in laminitis. The aims of this study were (1) to establish a laminitis grading scheme that can be applied to the wide spectrum of lesions seen in naturally occurring cases and (2) to measure and describe changes in the distal phalanx associated with laminitis using micro-computed tomography (micro-CT) and histology. Thirty-six laminitic and normal feet from 15 performance and nonperformance horses were evaluated. A laminitis grading sc...
Determining collagen distribution in articular cartilage using contrast-enhanced micro-computed tomography. Collagen distribution within articular cartilage (AC) is typically evaluated from histological sections, e.g., using collagen staining and light microscopy (LM). Unfortunately, all techniques based on histological sections are time-consuming, destructive, and without extraordinary effort, limited to two dimensions. This study investigates whether phosphotungstic acid (PTA) and phosphomolybdic acid (PMA), two collagen-specific markers and X-ray absorbers, could (1) produce contrast for AC X-ray imaging or (2) be used to detect collagen distribution within AC. Methods: We labeled equine AC sampl...
ANATOMICAL STUDY OF CRANIAL NERVE EMERGENCE AND SKULL FORAMINA IN THE HORSE USING MAGNETIC RESONANCE IMAGING AND COMPUTED TOMOGRAPHY. For accurate interpretation of magnetic resonance (MR) images of the equine brain, knowledge of the normal cross-sectional anatomy of the brain and associated structures (such as the cranial nerves) is essential. The purpose of this prospective cadaver study was to describe and compare MRI and computed tomography (CT) anatomy of cranial nerves' origins and associated skull foramina in a sample of five horses. All horses were presented for euthanasia for reasons unrelated to the head. Heads were collected posteuthanasia and T2-weighted MR images were obtained in the transverse, sagittal, and do...
Intraarterial Injection of Iodinated Contrast Medium for Contrast-Enhanced Computed Tomography of the Equine Head. Minimizing the volume of contrast administered for contrast-enhanced computed tomography (CT) of the equine head is desirable for reducing costs and risks of adverse reactions, however evidence-based studies on the effects of varying volumes on image quality are currently lacking. The objective of the current study was to determine whether low-volume intraarterial administration of contrast medium would result in an equivalent image quality and tissue attenuation vs. high-volume intravenous bolus administration. A prospective cross-over experimental design was used in a sample of six horses. A...
Update on disorders and treatment of the guttural pouch. The most common disorders of the equine guttural pouches are empyema, tympany, mycosis, and temporohyoid osteoarthropathy. Diagnosis of these conditions is made primarily by imaging with endoscopy, radiographs, computed tomography, and/or MRI. Medical treatment with anti-inflammatories, antimicrobials, and/or antifungals may be successful in some cases, but many of these disorders necessitate surgical intervention. Direct surgical approaches to the guttural pouch are difficult because of their complex anatomy and relationship with important structures, thus precipitating a move toward minimall...
Navigational ultrasound imaging: A novel imaging tool for aiding interventional therapies of equine musculoskeletal injuries. Navigational ultrasound imaging, also known as fusion imaging, is a novel technology that allows real-time ultrasound imaging to be correlated with a previously acquired computed tomography (CT) or magnetic resonance imaging (MRI) study. It has been used in man to aid interventional therapies and has been shown to be valuable for sampling and assessing lesions diagnosed with MRI or CT that are equivocal on ultrasonography. To date, there are no reports of the use of this modality in veterinary medicine. Objective: To assess whether navigational ultrasound imaging can be used to assist commonly...
Comminuted fracture of the accessory carpal bone removed via an arthroscopic-assisted arthrotomy. A 16-year-old American paint horse gelding was presented for evaluation of a left forelimb lameness grade III/V. Radiographs and computed tomography revealed a comminuted fracture of the accessory carpal bone involving the entire articulation with the distal radius and the proximal aspect of the articulation with the ulnar carpal bone. Multiple fragments were present in the palmar pouch of the antebrachiocarpal joint. An arthroscopic-assisted open approach was necessary to remove all fractured fragments. Subsequently the horse was re-admitted for lameness and was treated successfully with anti...
Relationship between the shape of the central and third tarsal bones and the presence of tarsal osteoarthritis. Osteoarthritis (OA) of the low motion joints of the tarsus, commonly termed 'bone spavin', is common in horses. Whilst the aetiology of this condition is multifactorial, it has been suggested that dorsal wedging of the central tarsal bone (CTB) and third tarsal bone (TTB) may predispose to the development of this disease. The aim of this study was to investigate the relationship between tarsal bone conformation and osteoarthritis of the proximal intertarsal (PIT), distal intertarsal (DIT) and tarsometatarsal (TMT) joints. It was hypothesised that wedging of the CTB and TTB would be associated ...
Comparison of radiographic and computed tomographic images of the lungs in healthy neonatal foals. To compare CT and radiographic images of the lungs in sedated healthy foals positioned in sternal recumbency and to investigate whether a relationship exists between CT-derived measurements of lung attenuation and Paco2 and Pao2. Methods: 6 healthy Standardbred foals < 14 days of age. Methods: Thoracic CT images were acquired followed by radiographic views with each foal sedated and positioned in sternal recumbency. For each foal, both CT and radiographic images were evaluated for severity and extent of changes by lung regions on the basis of a subjective scoring system by 3 investigators. ...
Ex Vivo Anatomical Characterization of Handsewn or Stapled Jejunocecal Anastomosis in Horses by Computed Tomography Scan. The aim of this study is to compare handsewn and stapled jejunocecal anastomosis with different stomal lengths in terms of anatomical differences. Group 1 underwent a two-layer handsewn jejunocecal side-to-side anastomosis (HS); Group 2 received a stapled jejunocecal side-to-side anastomosis (GIA). Each group was divided into two subgroups (HS80 and HS100, GIA80 and GIA100). Specimens were inflated and CT scanned. The stomal/jejunal area ratio and blind end pouch volume/area were measured and compared. Effective length of the stoma was measured and compared with the initial length. Stomal/jeju...
Validation of the accuracy of needle placement as used in diagnostic local analgesia of the maxillary nerve for investigation of trigeminally mediated headshaking in horses. Diagnostic local anaesthesia of the maxillary nerve is a valuable aid in the diagnosis of trigeminally mediated headshaking in horses. Our objective is to validate the accuracy of needle placement in this procedure and to identify any correlation between accuracy of the technique and operator experience. Using a small volume of contrast medium, the procedure was performed bilaterally on 30 horse cadaver heads by three groups with different levels of experience with the technique. The location of deposition was then identified using computed tomography (CT). Contrast medium was deposited around...
Validation study of an interpolation method for calculating whole lung volumes and masses from reduced numbers of CT-images in ponies. Quantitative computer tomographic analysis (qCTA) is an accurate but time intensive method used to quantify volume, mass and aeration of the lungs. The aim of this study was to validate a time efficient interpolation technique for application of qCTA in ponies. Forty-one thoracic computer tomographic (CT) scans obtained from eight anaesthetised ponies positioned in dorsal recumbency were included. Total lung volume and mass and their distribution into four compartments (non-aerated, poorly aerated, normally aerated and hyperaerated; defined based on the attenuation in Hounsfield Units) were de...
Gross, computed tomographic and histological findings in mandibular cheek teeth extracted from horses with clinical signs of pulpitis due to apical infection. The most prevalent type of equine dental pulpitis due to apical infection is not associated with coronal fractures or periodontal disease. The pathogenesis of this type of pulpitis is not fully understood. Computed tomography (CT) is increasingly used to investigate equine dental disorders. However, gross, tomographic and histopathological changes in equine dental pulpitis have not been compared previously. Objective: To compare gross, CT and histological appearances of sectioned mandibular cheek teeth extracted from horses with clinical signs of pulpitis without coronal fractures or periodont...