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.
Post-Mortem Computed Tomographic Features of the Most Caudal Lumbar Vertebrae, Anatomical Variations and Acquired Osseous Pathological Changes, in a Mixed Population of Horses. The radiographic, ultrasonographic, and scintigraphic findings of horses with thoracolumbosacral pain have been previously reported. In this study, the computed tomographic appearance of anatomical variations and pathological changes of the equine caudal lumbar region through a post-mortem examination were investigated. A total of 40 horses that had died or were submitted for euthanasia, for reasons unrelated to the study, were included in the study. From all the specimens, the modified vertebral system was adopted to evaluate and describe the four most caudal lumbar vertebrae, which were numb...
Identification of Heterotopic Mineralization and Adjacent Pathology in the Equine Fetlock Region by Low-Field Magnetic Resonance Imaging, Cone-Beam and Fan-Beam Computed Tomography. Heterotopic mineralization in equine distal limbs has been considered an incidental finding and little is known about its imaging features. The study aimed to identify heterotopic mineralization and adjacent pathology in the fetlock region with cone-beam (CB) computed tomography (CT), fan-beam (FB) CT, and low-field magnetic resonance imaging (MRI). Images from 12 equine cadaver limbs were examined for heterotopic mineralization and adjacent pathology and verified by macro-examination. Retrospective review of the CBCT/MR images from 2 standing horses was also included. CBCT and FBCT identified...
Identification of a previously unreported site of subchondral bone injury in the dorsodistolateral calcaneus in Thoroughbred racehorses. Increasing accessibility and advancements in computed tomographic (CT) imaging improve understanding of the contributors to poor performance in the Thoroughbred racehorse. Objective: To characterise an unreported site of tarsal subchondral bone injury (SBI) in Thoroughbred racehorses. Methods: Retrospective, cross-sectional analytical study. Methods: Tarsal CT scans of 108 horses were reviewed for evidence of SBI in the dorsodistolateral calcaneus (DDLC). Signalment, including age, breed, sex, and discipline of horses, was recorded. The association of DDLC SBI with Thoroughbred racehorse compa...
The prevalence of headshaking in horses with primary and secondary dental sinusitis and computed tomographic evidence of infraorbital canal pathology. Sinusitis is a common disease of horses yet there are a limited number of reports in the literature that describe the prevalence of infraorbital canal (IOC) pathology and headshaking behaviour in horses diagnosed specifically with primary sinusitis and secondary dental sinusitis. Given the impact that these behaviours can have on horses' intended athletic use, investigation is warranted. Objective: To determine the occurrence of IOC pathology in horses with concurrent primary or secondary dental sinusitis based on computed tomography (CT) findings and to assess whether the frequency of headsha...
The equine patellar ligaments and the infrapatellar fat pad – a microanatomical study. Interpretation of patellar ligament (PL) ultrasonography may be difficult, as hypoechoic or heterogenous echogenicity are common findings. Verifying suspected disease of equine PLs by histopathology is also problematic as descriptions of normal PL vascularity and histology are scarce. The current study describes the PL and infrapatellar fat pad (IFP) vascular pattern from computed tomography scans of barium perfused normal equine specimens (n = 8; age 10 days to 18 years), as well as routine histology to serve as a reference for future investigations into PL pathology and IFP disease. Re...
Immediate pre-operative computed tomography for surgical planning of equine fracture repair: A retrospective review of 55 cases. Fracture configuration is often more complex than is radiographically appreciable. The objective of this study is to describe the influence of pre-operative computed tomography (CT) for surgical planning in a variety of fracture types. This has not been described in previous studies. All cases with pre-operative radiographs, admitted for CT and surgical repair of a suspected limb fracture from January 2010-December 2020 were reviewed. CT was acquired under general anaesthesia in a multi-slice helical scanner; any surgery was then performed immediately. Three diplomates (two surgical; one diagn...
CT diagnosis of pituitary abscess, suppurative meningitis, and atlanto-occipital septic arthritis in a pony. A 15-year-old pony was presented for acute neurological signs. Neurological examination suggested a brainstem lesion, blood laboratory tests detected an active inflammatory process, and upper respiratory endoscopy identified a suppurative lesion at the dorsal aspect of the right guttural pouch. Computed tomography was performed and findings were consistent with pituitary abscess, meningitis, and atlanto-occipital joint septic arthritis. Imaging findings were confirmed based on cerebrospinal and synovial fluid cultures and necropsy. Computed tomography provided important information for identif...
Safety and accuracy of blind vs. ultrasound-guided dorsal retrobulbar nerve blocks in horses-A cadaveric study. There is limited knowledge regarding the safety and accuracy of ultrasound-guided retrobulbar nerve blocks in horses. The aim of this study was to compare these parameters between blind and ultrasound-guided injection techniques for the dorsal retrobulbar nerve block in horses. Methods: Equine cadaver heads were used to inject the retrobulbar space with contrast medium (CM). Injections were performed either blindly based on anatomic landmarks (blind group, n = 44) or under ultrasonographic guidance (US-group, n = 44), equally divided between an experienced and unexperienced operator. Needl...
Comparison of Six Different Methods for Measuring the Equine Hoof and Recording of its Three-Dimensional Conformation. Different measuring techniques have been used to objectify the classification of hoof shape. The MicroScribe is a novel tool that might prove useful for measuring hooves without prior reconstruction or compensation of projection artefacts. The aim of this study was to compare biometric data of the equine hoof collected by the MicroScribe tool and measurements collected directly from hooves, scaled photographs and radiographs, from photogrammetry models and computed tomography datasets. The suitability of MicroScribe generated data to differentiate individual hoof conformations was tested. A to...
Imaging techniques in veterinary medicine. Part II: Computed tomography, magnetic resonance imaging, nuclear medicine. Radiography and ultrasonography are the most used techniques in veterinary clinical practice, due to organizational, managerial and, mostly, economic reasons. However, in the last decades, Computed tomography (CT), Magnetic Resonance Imaging (MRI) and, to a lesser extent, Nuclear Medicine (MN) are increasingly used. As we said in the previous article, all the Diagnostic Imaging techniques are actually "indispensable" in Veterinary Medicine, where many patients do not show any symptoms.This second part describes Computed Tomography (CT), Magnetic Resonance (MRI) and Nuclear Medicine techniques ...
Computed tomographic evaluation of the distal limb in the standing sedated horse: Technique, imaging diagnoses, feasibility, and artifacts. In several veterinary institutions, adjustments of CT machines have been made that allow for imaging of the standing horse. The risk of general anesthesia is eliminated and the shorter scan completion time reduces cost to clients. The objective of this retrospective, analytical study was to evaluate the technique, imaging diagnoses, feasibility, and image artifacts of multi-slice helical CT of horses' distal limbs acquired under standing sedation. The CT images of 250 horses of various breeds, aged 3-23 years, that underwent standing distal limb CT were evaluated. Three observers assessed the ...
Impact of Different Diagnostic Procedures on Diagnosis, Therapy, and Outcome in Horses with Headshaking: Recommendations for Fast-Track Advanced Diagnostic and Therapeutic Protocols. Most horses affected by headshaking (HS) are diagnosed with idiopathic trigeminal-mediated headshaking (i-TMHS) when no underlying disease is found. Diagnosis is made by the exclusion of differentials considering history, clinical signs, and diagnostic investigations. Therefore, in horses presented with headshaking, many diagnostic procedures and therapies are conducted. Retrospectively, the digital patient records of 240 horses with HS were analysed regarding the impact of diagnostic procedures on diagnosis, therapy, and outcome. Horses were extensively examined using a standardised protocol ...
Novel computed tomographic analysis demonstrates differences in patterns of bone mineral content between fracture configurations in distal condylar fractures of the third metacarpal/metatarsal bones in 97 Thoroughbred racehorses. To evaluate bone mineral content patterns between fracture configurations using novel CT image analysis. Methods: CT images from 97 Thoroughbred racehorses with third metacarpal/tarsal condyle fractures provide the case population for analysis. Methods: Fractures were grouped by radiographic appearance. Image analysis objectively measured area of highly attenuating pixels (aHAP), areal density of highly attenuating pixels (dHAP) utilizing novel convex hull analysis, and subjective assessment of apparent attenuation intensity ranking (AAIR) for each fracture. Differences between fracture config...
Differences of morphological attributes between 62 proximal and distal subchondral cystic lesions of the proximal phalanx as determined by radiography and computed tomography. To determine morphological characteristics of subchondral cystic lesions (SCLs) in the proximal phalanx (PP) of adult horses. Methods: Radiographs and/or CT scans of PP from 46 horses. Methods: There were horses with a SCL in PP, which was diagnosed by radiography and/or computed tomography, included. Additional data (signalment, history, orthopedic examination) were collected retrospectively for each case. Results: Forty-six horses met the required inclusion criteria, with a total of 62 SCLs. Forty-three SCLs (70.5%) were located in the proximal PP (group A). Forty-four percent of these were ...
Computed tomography findings in horses presented with signs of head-shaking. Trigeminal nerve-mediated head-shaking (TNMH) in horses is a diagnosis made by exclusion. Computed tomography (CT) is frequently used to identify any disease process that could cause the clinical signs of head-shaking. Although abnormalities are frequently identified, it is unknown whether treatment of these conditions improves clinical signs. Objective: To ascertain the clinical significance of CT findings in horses presented with a complaint of head-shaking. Methods: Retrospective case series. Methods: CT and patient records were reviewed and all abnormal findings and any treatments subseque...
CT measures of osseous cervicothoracic intervertebral foramina are repeatable and associated with CT measures of adjacent articular processes in horses. Narrowing of the equine cervicothoracic intervertebral foramina (IF) has the potential to cause forelimb lameness and/or neck pain although limited information is available on CT of the IF. The aims of this retrospective, analytical study were to describe a protocol for quantifying CT cervicothoracic IF size; evaluate the repeatability of IF size measures; test associations between IF size and adjacent articular process (AP) size, ventral extent, and anatomic location; and determine the proportion of IF with narrowing. Computed tomographic images were acquired in 20 Warmblood horses that prese...
Computed tomographic arthrography, gross anatomy and histology demonstrate a communication between synovial invaginations in the proximal aspect of the third interosseous muscle and the carpometacarpal joint in horses. This descriptive anatomical study investigates the relationship between the third interosseous muscle, also known as the suspensory ligament, and the carpometacarpal joint in forelimbs of horses, with the hypothesis that there was a direct synovial communication between these structures as shown by computed tomographic arthrography, histology, and gross anatomy sections. Computed tomography of the carpus and metacarpal region was performed on two groups. Group 1 consisted of eight cadaver limbs undergoing computed tomographic arthrography following injection of a mixture of positive contrast m...
Disseminated Hemangiosarcoma in a Mare Mule. An 8-year-old mare mule was presented with a facial mass and history of anorexia, unilateral epistaxis and purulent nasal discharge. The facial mass was encountered from the ventral to the lateral right canthus of the eye up to the facial crest. Thoracic ultrasonography showed five rounded masses. A standing CT under sedation was performed revealing a huge extension and infiltration on surrounding tissues. Due to the extension, type of lesions, outcome and suspicion of metastasis, the owner chose to euthanize the patient. Necropsy confirmed the presence of tumoral lesions spread into the lungs...
Sex differences in cervical spinal cord and spinal canal development in Thoroughbred horses. Cervical vertebral stenotic myelopathy (CVSM), a common cause of cervical spinal cord compression, is a neurological disease characterized by general proprioceptive ataxia and weakness of hindlimbs that tends to develop in young adult Thoroughbred horses. Although male horses seem to be at increased risk for CVSM, the mechanism for the occurrence of sex differences in the prevalence of CVSM is still poorly understood. Hence, we hypothesized that sex differences in the development of cervical spinal cord and spinal canal would affect the development of CVSM. This study aimed to evaluate sex dif...
An Extra-Articular Surgical Approach to Subchondral Bone Cysts in the Humeral Head and Talus in Two Horses. To date, only a few reports describe the treatment. The present report describes an extraarticular surgical approach, with the insertion of an absorbable implant, to treat a Subchondral cystic lesion (SCL) in the humeral head 3year old racing Thoroughbred & in the talus of a 11year old Arabian horse. SCLs were radiographically visible and associated with severe lameness. Scintigraphy showed focal intense radiopharmaceutical uptake in both cases, and CT scan revealed signs of osteoarthrosis associated with SCL in the talus. The use of a biocompatible, osteoinductive and osteoconductive implant ...
An anatomical study of the skull, the dorsal and ventral nasal conchal bullae and paranasal sinuses in normal Noma horses: Computed tomographic anatomical and morphometric findings. Noma horses have the smallest body size among native Japanese horses and are classified as pony breeds by their size. Additionally, the Japanese horse breeds are classified into a single lineage, which includes Mongolian horses. Great intraspecific differences reportedly exist in the head shapes of domesticated horses, which have been investigated in various horse breeds. The present study aimed to evaluate the size of the nasal conchal bullae, and the paranasal sinuses of Noma horses in relation to the skull dimensions using computed tomography. Reconstructed images of the heads of five adult...
Equine Incisor Lesions: Histologic Confirmation of Radiographic, Macroscopic, and Micro-Computed Tomographic Findings. Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH) and other incisor lesions are often diagnosed only in advanced stages. The incisors of 20 horses were examined radiographically, macroscopically, and via micro-computed tomography (µCT) to discriminate EORTH-affected teeth. Five categories from healthy to severely affected teeth were formed and teeth from each category were examined histologically to evaluate the opportunity of earlier radiographic diagnosis. Histologically, odontoclastic resorptive lesions, leukocytic infiltrations, and areas of irregular cementum and granulat...
Special Diagnostic Techniques in Equine Neurology (Radiography, Ultrasonography, Computed Tomography, and Magnetic Resonance Imaging). Diagnostic imaging is often an important part of the diagnostic approach to neurologic disease. Advanced imaging techniques such as myelography, computed tomography (CT), and magnetic resonance imaging (MRI) provide more information than radiography and ultrasonography but are more limited in their availability. The clinician should be cognizant of the findings of the clinical examination when interpreting diagnostic imaging findings.
Use of a novel helical fan beam imaging system for computed tomography of the distal limb in sedated standing horses: 167 cases (2019-2020). To evaluate the diagnostic capabilities of a novel helical fan beam CT system used for imaging of horses with a range of clinical distal limb problems. 167 horses. Medical records were reviewed of horses presented for CT of the distal limb at 2 university-based veterinary hospitals. The following data were recorded: age, sex, breed, presenting complaint, sedation used for imaging, scanning time, procedure time, other diagnostic imaging methods performed, imaging diagnosis, clinical diagnosis, and complications during imaging. Most horses were Thoroughbreds and Quarter Horses. Procedure times r...
Percutaneous doxycycline sclerotherapy in a horse with a mandibular aneurysmal bone cyst. To describe the use and outcome of sclerotherapy with intralesional doxycycline foam in a horse with a mandibular aneurysmal bone cyst. Methods: Case report. Methods: Client-owned 1 year old Standardbred filly. Methods: The horse presented for progressive mandibular swelling. A 10 mg/mL doxycycline foam was prepared for intralesional injection. Three doses were injected into the lesion under computed tomographic guidance at 6 and 15 weeks after initial treatment. Volume reduction was monitored after each treatment with 3D volumetric rendering and region of interest segmentation using commer...
Use of a novel helical fan beam imaging system for computed tomography of the head and neck in sedated standing horses: 120 cases (2019-2020). To evaluate the diagnostic capabilities of a novel helical fan beam CT system used for imaging of horses with clinical problems of the head and neck. 120 horses. Medical records were reviewed of horses presented for CT of the head or neck at 2 university hospitals. The following data were recorded: age, sex, breed, presenting complaint, sedation used for imaging, scanning time, procedure time, other diagnostic imaging methods performed, imaging diagnosis, clinical diagnosis, and complications during imaging. Quarter Horses and Warmbloods were the most common breeds, and the most common complai...
Investigation of a contributing factor for cervical vertebral stenotic myelopathy using computed tomography for measuring the cervical vertebral volume. Thoroughbred horses appear to be particularly predisposed to cervical vertebral stenotic myelopathy (CVSM), also known as wobbler syndrome. We hypothesized that variations in the cervical vertebral volumes can affect the dynamic instability of the cervical vertebrae. This observational study aimed to clarify whether cervical vertebral volume could be considered as a contributing factor in CVSM in Thoroughbred horses. Computed tomography (CT) was used to investigate a total of 21 male Thoroughbred horses (age range, 217-1,002 days; mean, 542.3 days). The study population comprised 17 CVSM horse...
Kinematics of the equine distal sesamoid (navicular) bone of the thoracic limb. To quantify the translation and angular rotation of the distal sesamoid bone (DSB) using computed tomography (CT) and medical modeling software. Methods: 30 thoracic limbs from equine cadavers. Methods: Partial (n = 12), full (8), and matched full and subsequently transected (10) thoracic limbs were collected. Bone volume CT images were acquired in three positions: extension (200° metacarpophalangeal angle), neutral (180°), and maximal flexion (110°). Mean translation and angular rotation of each DSB were recorded. Differences were determined with two-way ANOVA and post hoc Tukey's tests fo...
Unilateral, Rostral Maxillary Sinusitis Resulting from Displacement and Retention of an Alveolar Plug in a 4-Year-Old Horse. Sinusitis is a common occurrence in horses and often develops secondary to dental disease. Extraction of cheek teeth in horses is associated with variable degrees of complications and although postoperative displacement and retention of alveolar plugs has been identified as one such potential complication, few cases of resulting sinusitis have been reported. This manuscript describes a four-year-old Thoroughbred mare that was presented for chronic unilateral left-sided mucopurulent nasal discharge after extraction of the left maxillary second molar tooth two months earlier. Radiographic and co...
The Impact of Circular Exercise Diameter on Bone and Joint Health of Juvenile Animals. Circular exercise is used in many equestrian disciplines and this study aimed to determine if circle diameter impacts juvenile animal forelimb bone and joint health. On day 0, 24 calves at 9 weeks of age were assigned the following exercise treatments: small circle (12 m clockwise), large circle (18-m clockwise), treadmill, or non-exercised control. Exercise was initiated at 1.1−1.5 m/s for 5 min/d and increased 5 min weekly until reaching 30 min/d. On day 49, synovial fluid was collected from multiple joints, cartilage was collected from the proximal surface of fused third and fourth metaca...