Veterinary radiology & ultrasound : the official journal of the American College of Veterinary Radiology and the International Veterinary Radiology Association.
Publisher:
American College Of Veterinary Radiology. Oxford : Blackwell
Frequency: Bimonthly
Country: England
Language: English
Author(s):
American College of Veterinary Radiology., International Veterinary Radiology Association.
Start Year:1992 -
ISSN:
1058-8183 (Print)
1740-8261 (Electronic)
1058-8183 (Linking)
1740-8261 (Electronic)
1058-8183 (Linking)
Impact Factor
1.7
2022
| NLM ID: | 9209635 |
| (DNLM): | SR0073746(s) |
| (OCoLC): | 24384362 |
| Coden: | VRULED |
| Classification: | W1 VE9332JF |
The value of radiographic screening for metallic particles in the equine foot and size of related artifacts on low-field MRI. Magnetic susceptibility artifacts as a result of metal debris from shoeing are a common problem in magnetic resonance imaging of the equine foot. Our purpose was to determine the suitability of radiography as a screening tool for the presence and location of metallic particles in the equine foot and to predict the size of the resultant magnetic susceptibility artifact. Radiography had 100% sensitivity for detection of metal particles > or = 1 mm diameter. Metal particles of known diameter were placed within the hoof wall of 22 cadaver feet and scanned with a low-field strength MR imaging un...
Starry sky hepatic ultrasonographic pattern in horses. The starry sky hepatic pattern is an unusual ultrasonographic appearance of equine liver characterized by numerous small, hyperechoic foci, some of which cast an acoustic shadow, distributed randomly throughout the hepatic parenchyma. Our objectives were to describe the signalment, clinical signs, clinicopathological findings, primary disease process, and ultrasonographic findings of horses with this ultrasonographic pattern, as well as determine the associated gross and histologic changes. The starry sky pattern was identified in 18 adult horses of mixed gender and breed. The horses had vario...
Magnetic resonance imaging in foals with infectious arthritis. The magnetic resonance (MR) imaging findings of foals with infectious and noninfectious arthritis are described. Six foals with infectious arthritis and three foals with noninfectious arthritis were grouped based on synovial fluid analysis results and examined with radiography and MR imaging. Four out of six foals with infectious arthritis had osseous lesions in MR images indicative of osteomyelitis and only 4/19 lesions were detected on digital radiographs. The three foals with noninfectious arthritis had no osseous lesions in MR images or radiographically. Of the six joints that had osseous ...
Comparison of radiographic and scintigraphic findings of the spinous processes in the equine thoracolumbar region. Back pain is common in horses, but there has been no large-scale in-depth study describing radiographic changes of the spinous processes, the relationship between radiographic and scintigraphic findings, and the effect of size, age, breed, or discipline. The objectives were to investigate the frequency of occurrence in horses with perceived back pain of: (1) radiographic alteration of the spinous process structure; (2) increased radiopharmaceutical uptake (IRU) in the spinous processes; and (3) to compare radiographic and scintigraphic findings; and to determine if there was breed, gender, age...
The use of computed tomographic three-dimensional reconstructions to develop instructional models for equine pelvic ultrasonography. Ultrasonography has gained increased utility to diagnose pelvic fractures in horses; however, internal pelvic contours can be difficult to appreciate from external palpable landmarks. We developed three-dimensional (3D) simulations of the pelvic ultrasonographic examination to assist with translation of pelvic contours into two-dimensional (2D) images. Contiguous 1mm transverse computed tomography (CT) images were acquired through an equine femur and hemipelvis using a single slice helical scanner. 3D surface models were created using a DICOM reader and imported into a 3D modeling and animatio...
Positive contrast magnetic resonance bursography for assessment of the navicular bursa and surrounding soft tissues. Magnetic resonance (MR) imaging is often performed to determine the cause of palmar heel pain. We evaluated how distension of the navicular bursa affected the MR appearance of the navicular bursa and associated structures. An MR evaluation was performed on normal cadaver limbs and cadaver limbs from horses with lameness localized to the foot. The normal navicular bursae were injected with 2, 4, or 6 ml of solution. The bursae of the feet from lame horses were injected with 4 or 6 ml, and the MR study was repeated. All bursae were examined grossly to verify the presence or absence of adhesions....
Fractures of the distal phalanx and associated soft tissue and osseous abnormalities in 22 horses with ossified sclerotic ungual cartilages diagnosed with magnetic resonance imaging. Ungual cartilage ossification in the forelimb is a common finding in horses. Subtle abnormalities associated with the ungual cartilages can be difficult to identify on radiographs. Magnetic resonance (MR) imaging findings of 22 horses (23 forelimbs) with a fracture of the distal phalanx and ossified ungual cartilage were characterized and graded. All horses had a forelimb fracture. Eleven involved a left forelimb (seven medial; four lateral), and 12 involved a right forelimb (five medial; seven lateral). All fractures were nonarticular, simple in configuration, and nondisplaced. The fractures ...
Clinical relevance of abnormal scintigraphic findings of adult equine ribs. Horses with cranial rib abnormalities may exhibit severe acute lameness and may have unusual gait deficits characterized by forelimb abduction during protraction at the walk. Horses with caudal rib abnormalities may resent being saddled and ridden. In a retrospective evaluation of 20 horses with a documented rib lesion, 25 sites of increased radiopharmaceutical uptake were found in one or more ribs. Thirteen (52%) scintigraphic lesions involved the first rib; four were located immediately dorsal to the sternal articulation, eight were near the costochondral junction and one was at the costover...
Reaction to intraarterial ionic iodinated contrast medium administration in anesthetized horses. The purpose of this report was to evaluate the frequency and type of reactions to intraarterial iodinated contrast medium injection in horses. Ninety-seven received an intraarterial injection of ionic, iodinated contrast medium for computed tomographic assessment of the distal limb. Nine (9.0%) horses developed a reaction attributable to the contrast medium administration. Of those, 4/97 (4.0%) developed a skin response (three with urticaria, one with facial edema) within 20 min. Five (5.0%) developed elevation of heart rate and/or blood pressure immediately upon administration of the contrast...
Magnetic resonance imaging findings in horses with septic arthritis. Fourteen horses with septic arthritis underwent high-field (1.5 T) magnetic resonance imaging (MRI). Septic arthritis was diagnosed based on results from historical and clinical findings, synovial fluid analyses and culture, and radiographic, ultrasonographic, arthroscopic, and histopathologic findings. MR findings included diffuse hyperintensity within bone and extracapsular tissue on fat-suppressed images in 14/14 horses (100%), joint effusion, synovial proliferation, and capsular thickening in 13/14 horses (93%), bone sclerosis in 11/14 horses (79%), and evidence of cartilage and subchondra...
Sonographic characteristics of intraabdominal abscessation and lymphadenopathy attributable to Rhodococcus equi infections in foals. The sonographic characteristics of intraabdominal abscesses in 11 foals and intraabdominal lymphadenitis in five foals with Rhodococcus equi infections are presented. Intraabdominal abscesses were usually present in the ventral abdomen adjacent to the ventral body wall, well-marginated, and contained a mixed or complex echo pattern. Lymphadenitis appeared as singular or multiple clusters of lymph nodes of mixed echogenicity adjacent to any portion of the gastrointestinal tract or body wall. Sonographic findings were supported by necropsy examinations, but sonographic measurements consistently ...
Identification and prevalence of errors affecting the quality of radiographs submitted to Australian thoroughbred yearling sale repositories. We aimed to identify common mistakes made when radiographing yearling sale horses. Radiographic examinations from repositories at eight yearling sales held in Australia in 2003 were assessed by one of four veterinary radiology specialists. Each radiographic examination consisted of a maximum of 34 radiographs. Each radiograph was assessed for errors associated with movement, exposure, positioning, labeling or marker placement, and processing, and categorized as either ideal, less than ideal or nondiagnostic. In addition, from the first 800 sets catalogued, 167 were selected randomly and read t...
Radiography and computed tomography in the diagnosis of nonneoplastic equine mandibular disease. We compared the information gained from computed tomography (CT) vs. radiography in horses with nonneoplastic disease of the mandible. We hypothesized that CT would provide additional diagnostic information. Medical records, radiographs, and CT images of horses with nonneoplastic mandibular disease evaluated between 1994 and 2008 were reviewed. Nineteen horses were identified; 11 had a tooth root abscess and related disease, four had a fracture of the teeth and/or mandible, and four had a nonneoplastic mass. Both CT images and radiographs allowed identification of diseased teeth that appeared ...
The appearance of the equine metacarpophalangeal region on high-field vs. standing low-field magnetic resonance imaging. The appearance of the equine metacarpophalangeal (MCP) joint on high-field (1.5 T) vs. low-field standing (0.27 T) magnetic resonance (MR) images was evaluated. Objectives were (1) to describe the MR appearance of anatomic structures of clinical interest on images of the equine MCP joint obtained from 20 equine cadaver limbs from horses without lameness using high-field and low-field systems, (2) to categorize the clarity of appearance of anatomic structures on low-field MR images in comparison to high-field images as a gold standard. We found that larger anatomic structures were visible with ...
Ultrasonographic findings in horses with foot pain but without radiographically detectable osseous abnormalities. Foot pain is an important cause of lameness in horses. When horses with foot pain have no detectable radiographic abnormalities, soft-tissue assessment remains a diagnostic challenge without magnetic resonance (MR) imaging. Ultrasonography can provide an alternative to MR imaging when that modality is not available but the extent of changes that might be seen has not been characterized. We reviewed the ultrasonographic findings in 39 horses with lameness responding positively to anesthesia of the palmar digital nerves and without radiographically detectable osseous abnormalities. Thirty of the...
Magnetic resonance anatomy of the carpus of the horse described from images acquired from low-field and high-field magnets. Cadaver carpi of 30 mature horses with no history of carpal or proximal metacarpal pain were examined using low-field (0.27 T) and high-field (1.5 T) magnetic resonance imaging (MRI). Normal MRI anatomy in transverse, sagittal, and dorsal plane images was determined by comparison with anatomical specimens and standard texts. Subchondral bone and cortical bone thickness measurements were obtained from standardised sites. There was variable subchondral bone thickness in the radius and carpal bones; subchondral bone thickness was consistently larger at dorsal compared with palmar sites in the...
Magnetic resonance imaging features of serous atrophy of bone marrow fat in the distal limb of three horses. Emaciated human patients have changes in the fat content in medullary bone that are consistent with serous atrophy of the bone marrow histologically. Serous atrophy has been identified at postmortem examination in horses; however, the magnetic resonance (MR) characteristics have not been documented. Herein we describe the abnormalities of the bone marrow and medullary bone detected by low-field and high-field MR imaging of the distal limbs of three emaciated horses. These low- and high-field MR imaging abnormalities are characterized by a decrease in signal intensity on T1-weighted images in c...
Radiologic anatomic variation of the carpus in horses with carpal lameness and control horses. Our purpose was to describe the variation of the radiologic appearance of the carpus of horses of different breeds, discipline, and gender with lameness related to the carpus and control horses, with particular reference to the ulnar carpal bone. Two hundred and eighty-six sets of carpal radiographs from 222 horses were analyzed. Breed, gender, discipline, and cause of lameness were recorded. Chi square tests were used to test for associations between radiologic findings and gender, breed and discipline, to test for associations between different radiologic findings, and to test for associatio...
Quantitative pertechnetate thyroid scintigraphy and the ultrasonographic appearance of the thyroid gland in clinically normal horses. We characterized the scintigraphic and sonographic appearance of the thyroid gland in clinically normal horses to establish the value of these modalities for assessment of the thyroid gland in this species. Horses were divided into two age groups. One group consisted of eight horses between 3 and 10 years of age and the other of seven horses between 11 and 20 years of age. Total T4 concentrations were within the laboratory reference interval in all horses. Thyroid to salivary (T/S) ratio, percent dose uptake of pertechnetate (Na99mTcO4) and thyroid lobe volume were calculated. The echogenicity...
Repeatability and reproducibility of transabdominal ultrasonographic intestinal wall thickness measurements in Thoroughbred horses. The aims of this study were to assess the repeatability and reproducibility of transabdominal ultrasonography to assess intestinal wall thickness in adult Thoroughbred horses (n = 8). Ultrasonographic cineloops were captured by one examiner from each horse for five consecutive days. During each examination at least three cineloops were obtained for five different intestinal tract locations. Measurements were performed by three separate observers to assess reproducibility and measured on three separate occasions by three observers to evaluate short-term repeatability. The repeatability of measu...
Effects of fasting and intraluminal contrast enhancement on ultrasonographic appearance of the equine small intestine. The equine small intestine is challenging to evaluate ultrasonographically. In humans, hydrosonography has been used to improve ultrasonographic images of the small intestine. We hypothesized that fasting horses for 24 h would enhance the ability to image the small intestine transabdominally by separating intestinal loops and reducing intraluminal gas, and that the administration of intragastric contrast agent would further improve that ability. Ten healthy horses were examined ultrasonographically under three treatment conditions: (a) regular diet, (b) after a 24-h fast, and (c) fasted plus i...
The effect of sequence selection and field strength on detection of osteochondral defects in the metacarpophalangeal joint. 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...
Transrectal ultrasonography of the left adrenal gland in healthy horses. Little information is available on medical imaging of the adrenal glands in horses. We investigated the feasibility of transrectal ultrasonography to characterize the normal equine adrenal gland. Transrectal ultrasonography was performed in 25 healthy horses using a 7.5 MHz linear array probe at a displayed depth of 8 cm. Transrectal ultrasonography of the right adrenal gland was not feasible. For the left adrenal gland, the left kidney, the abdominal aorta, the left renal artery, the left renal vein, and the cranial mesenteric artery were used as landmarks. The size of the left adrenal gland ...
Effect of head and neck position on pharyngeal diameter in horses. Dynamic nasopharyngeal collapse with upper airway obstruction is an important cause of exercise intolerance in performance horses. Its underlying pathophysiology is not fully understood. We hypothesize that head position affects pharyngeal diameter, and thus head position may be a contributing factor to nasopharyngeal obstruction. Fifteen adult healthy horses were subjected to endoscopy and radiography at rest. The pharyngeal diameter was measured at nine different head and neck positions. The effect of sedation and breathing cycle on the pharyngeal diameter was determined, and the relationshi...
Ultrasonographic findings in the lumbosacral joint of 43 horses with no clinical signs of back pain or hindlimb lameness. The transrectal ultrasonographic appearance of the lumbosacral joint was assessed in 43 horses with no history or clinical evidence of back pain or hindlimb lameness. In the majority of horses (34/43, 79.1%) the lumbosacral disc had uniform or mildly heterogeneous echogenicity. However, variation in the ultrasonographic appearance of the lumbosacral joint was also identified, including hyperechogenic regions within the lumbosacral disc with or without an acoustic shadow, and mild or moderate irregularity of the opposing surfaces of the last lumbar and the first sacral vertebral bodies. Marked ...
Resolution of lesions on STIR images is associated with improved lameness status in horses. Magnetic resonance (MR) imaging is important in diagnosing musculoskeletal injuries in horses. However, there is still much to learn regarding the significance of lesions identified in equine MR images. Of particular importance is the clinical significance of signal change as a function of pulse sequence. We hypothesized that a resolution of tendon, ligament, and bone marrow lesions on short-tau inversion recovery (STIR) images would be associated with a return to soundness, and that a persistence of tendon and ligament lesions on only T1-weighted (T1w) gradient recalled echo (GRE) images woul...
Imaging diagnosis–nasal septal and laryngeal cyst-like malformationsin a Thoroughbred weanling colt diagnosed using ultrasonography and magnetic resonance imaging. A foal was examined for abnormal upper airway noise. Endoscopically, there were narrowed nasal passages and an extralumenal mass of the cranial trachea. Using ultrasonography and magnetic resonance (MR) imaging of the larynx and cranial cervical trachea, irregular margins of the laryngeal cartilages and first tracheal ring containing areas consistent with fluid were identified. In MR images, a widened nasal septum was seen that contained material consistent with fluid. Postmortem examination confirmed the diagnosis of nasal septal, laryngeal, and cranial cervical tracheal cyst-like lesions. Th...
Determination of T1 relaxation time of normal equine tendons using magic angle magnetic resonance imaging. Seven isolated equine front limbs were used to establish the normal T1 relaxation time of equine superficial digital flexor tendon (SDFT), deep digital flexor tendon (DDFT), and suspensory ligament (SL) using magic angle magnetic resonance (MR) imaging. MR imaging of the metacarpi was performed with the limbs positioned at 55° (the magic angle) relative to the main magnetic field. Transverse spin-echo proton density and inversion recovery images were acquired. T1 relaxation time was calculated based on ratios of signal intensity determined from the different pulse sequences. T1 relaxation tim...
Estimated operator exposure for hand holding portable X-ray units during imaging of the equine distal extremity. Hand holding of portable X-ray units is common in large animal ambulatory veterinary practice. Portable X-ray equipment manuals, veterinary teaching institutions, and state regulations discourage, or prohibit, hand holding of portable X-ray units. Our goal was to quantify surface radiation leakage of a typical portable X-ray unit and to measure operator exposure at simulated hand and collar positions during imaging of the equine distal extremity. Each exposure for the study was performed at 80 kVp and 7.5 mAs and repeated 10 times. Measurement of tube radiation leakage was performed along each...