Topic:Imaging Techniques
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.
Computerized ultrasonographic tissue characterization of equine superficial digital flexor tendons by means of stability quantification of echo patterns in contiguous transverse ultrasonographic images. To describe a method of computerized ultrasonographic tissue characterization that includes structures below the size limits of resolution in equine superficial digital flexor tendons. Methods: 2 damaged and 2 structurally normal superficial digital flexor tendons. Methods: Transverse ultrasonographic images were collected along the tendon long axis. Stability of echo pattern was quantified by means of variation in gray levels of each pixel in contiguous images and expressed as correlation, entropy, and waviness ratios. Results: Normal young and normal old tissues were characterized by high co...
Ultrasonographic abnormalities detected in the sacroiliac area in twenty cases of upper hindlimb lameness. The pelvis is covered with extensive musculature and often presents a challenge in diagnostic imaging. Ultrasonography provides diagnostic information about soft tissue, articular cartilage and bone surfaces, although little information exists about the normal ultrasonographic appearance of the equine sacroiliac region. Objective: To determine the clinical applicability of ultrasonographic examination in horses with sacroiliac pain. Methods: Horses presented to the University of Minnesota Veterinary Teaching Hospital for hindlimb lameness were evaluated and lower limb lameness was ruled out wi...
New approach for quantitative assessment of articular cartilage degeneration in horses with osteoarthritis. To evaluate a modified digital imaging technique for quantitative assessment of the grade of osteoarthritis across the proximal articular surface of the first phalanx in horses. Methods: 6 metacarpophalangeal (fet-lock) joint specimens from 6 horses with various stages of osteoarthritis. Methods: First phalanx specimens, together with 4 gray scale reference calibration targets, were positioned in a bath with the proximal articular cartilage surface submerged in saline (0.9% NaCl) solution. Digital images were obtained from the articular surface before and after staining with Indian ink. Comput...
Magnetic resonance for evaluation of neurologic disease in 12 horses. 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. ...
A radiographic technique to assess the longitudinal balance in front hooves. The aim of this study was to validate a radiographic technique to measure objectively the longitudinal hoof balance in the horse. Ten left third phalanges (P3) obtained from front hooves and 19 left front hooves were used in order to assess the reliability of the radiographic technique and to identify any effect of rotation or alignment of specimens or distance between the X-ray machine and the radiographic cassette, in measuring P3s structures and balance related parameters. A rotational support was made to hold specimens in order to standardise some of the conditions of X-raying. The main ax...
Ultrasonographic measurements of accessory sex glands, ampullae, and urethra of normal stallions of various size types. For the purpose of establishing clinical reference values, this paper reports results of ultrasonographic examination and measurement of accessory sex glands, ampullae, and the pelvic urethra of 102 mature, healthy breeding stallions (2-29 years of age) of various size types (7 Miniature Horses, 27 small ponies, 53 light horses and 15 heavy horses). Examinations were done per rectum in mostly unsedated stallions using an Aloka 210 scanner with a 7.5 MHz linear veterinary transrectal transducer (Corometrics Medical Systems, Inc., North Wallingford, CT, USA). Most measures of accessory sex gland...
Comparison of computed radiography and conventional film-screen radiography of the equine stifle. Major advantages of computed radiography are the potential reduction of dose and the possibility of postprocessing. In our study, we compared conventional radiographs to digital radiographs of the equine stifle by subjective evaluation of diagnostic quality when using a decreasing photon flux (mAs). Twelve equine stifle joints from horses of different weight and size were examined. Conventional and digital radiographs were performed identically in a caudocranial projection with the tube angled 15 degrees. A series of four radiographs was performed in each technique with an increasing photon fl...
Use of multisite quantitative ultrasonography for noninvasive assessment of bone in horses. To evaluate the usefulness of multisite quantitative ultrasonography for noninvasive assessment of bone in horses. Methods: 12 healthy horses and both forelimbs from 8 clinically normal horses. Methods: For in vivo measurements, various regions of interest (ROI) were examined on the third metacarpal bone, radius, and tibia. Precision error for speed of sound (SOS) measurements was obtained by measuring each ROI of 4 horses 10 times with probe repositioning. Additionally, 3 operators measured each aspect of the third metacarpal bone of 6 horses 5 times each. For ex vivo measurements, third meta...
Reliability of ultrasonography compared to radiography in revealing intestinal sand accumulations in horses. In order to investigate the reliability of ultrasonography in revealing intestinal sand accumulations, the cranioventral parts of the abdomen of 32 horses (age 3-20 years) with signs suggestive of gastrointestinal sand were examined radiographically and ultrasonographically. The amount of sand and its localisation, relative to the ventral abdominal wall, were evaluated radiographically and graded (scale 0-4). Motility of the intestine and whether it was lying against the ventral abdominal wall were evaluated ultrasonographically and the findings summed and graded (scale 0-3) to express the lik...
Use of infrared thermography to detect injections and palmar digital neurectomy in horses. Thermography is a non-contact, non-invasive technique that detects surface heat emitted as infrared radiation. Because skin temperature reflects the status of underlying tissue metabolism and blood circulation, abnormal thermal patterns can signify areas of superficial inflammation. The objective of this study was to determine if thermography could detect the injection of analgesic and neurolytic agents and surgical palmar digital neurectomy. Procedures evaluated include injection of the lumbar region, suspensory ligaments, tibial nerve, palmar digital nerves, and palmar digital neurectomy. Th...
Magnetic resonance imaging application to live horse for diagnosis of tendinitis. Six live horses with various stages of acute to chronic superficial digital flexor (SDF) tendinitis were examined using magnetic resonance imaging (MRI). In each case, MRI findings were compared to the corresponding ultrasonographic (USD) and histologic findings, to establish the usefulness of MRI. In the acute cases, lesions characterized by hemorrhage were well defined as high signal intensity on MRI and hypoechoic regions on USD. Chronic tendon fibrosis was slightly hyperechoic and difficult to distinguish from the normal tendon tissue around the original injury by using USD. In contrast, M...
The scintigraphic anatomy of the equine sacroiliac joint. The aim of this study was to describe the scintigraphic appearance and location of the sacroiliac joint (SI-joint) in dorsal and dorso 30 degree lateral views of the equine pelvis in a scintigram. The pelvis from 10 different horses was prepared by attaching plastic tubes along relevant margins of the bone and around the SI-joint. A radioactive solution was injected into the tubes, and scintigraphic images were acquired with a gamma camera. Five specific landmarks were identified on the left and right sides of the pelvis. There was no significant difference in the distance measurements between...
Anatomic reference for computed tomography of the head of the foal. The purpose of this study was to produce an anatomic reference for computed tomography (CT) of the head of the foal for use by radiologists, clinicians, and veterinary students. The head from each of 2 foals, euthanized for reasons unrelated to head pathology, was removed and prepared for CT scanning. Using a third-generation CT scanner, 5-mm contiguous transverse images were acquired. The heads were then frozen and sectioned using a band saw, with the cuts matched as closely as possible to the CT slices. The anatomic sections were photographed and radiographed. The radiographs and anatomic ph...
Ultrasonography of the podotrochlear apparatus in the horse using a transcuneal approach: technique and reference images. The purpose of this paper is to describe the technique for ultrasonographic examination of the podotrochlear apparatus in the horse using a transcuneal approach. In this study, ultrasound scans were performed in 3 normal cadaver limbs and 5 sound horses and images were compared to anatomic sections to establish the normal ultrasonographic anatomy of the podotrochlear apparatus. Detailed description of transverse and sagittal reference ultrasonographic images of this region is provided. This new imaging technique allows the assessment of the distal sesamoid bone flexor surface, the distal porti...
Analysis of a radiographic technique for measurement of equine metacarpal bone shape. Accuracy and limitations of a radiographic technique were established for measurement of metacarpal bone shape in horses. A radiographic index (RI) has been used to measure changes in third metacarpal (Mc3) bone shape in response to training in young racehorses. The aim of these experiments was to determine the effects of positioning of the radiographic equipment on RI measurements from lateromedial radiographs of a left ex vivo metacarpus. Repeatability of the RI measurement in left lateromedial and right mediolateral view Mc3s were evaluated. The width of the dorsal cortex (DC), palmar corte...
Phacofragmentation for morgagnian cataract in a horse. A 3-year-old Paint gelding was presented for sudden onset of cataract affecting the right eye. Ophthalmic examination revealed subtle to mild microphthalmia and a mature cataract affecting the right globe. The right eye was treated with an antibiotic-corticosteroid ophthalmic ointment and phacofragmentation was recommended. On re-examination 5 months later, resorption of the cortex of the right lens and a morgagnian cataract were evident. The nucleus was positioned ventronasally in the lens capsule. The right eye had light perception, and a menace response was present. Examination of the right...
The application of three-dimensional internal structure microscopy in the observation of mare ovary. The ovary of the mare has a unique structure which differs totally from that of other mammals. However, because of its relatively large size, conventional histological techniques were unsuitable for the observation of the internal structure of the whole ovary. Three-dimensional internal structure microscopy (3D-ISM) consists of a cryotome-CCD camera-laser disc recorder-PC-based control system coupled with a graphic workstation. The internal structure of the ovary is observed by processing over more than 1,000 stored images of serially sliced surfaces of each frozen equine ovary. The 3D reconst...
The role of thermography in the management of equine lameness. Equine thermography has increased in popularity recently because of improvements in thermal cameras and advances in image-processing software. The basic principle of thermography involves the transformation of surface heat from an object into a pictorial representation. The colour gradients generated reflect differences in the emitted heat. Variations from normal can be used to detect lameness or regions of inflammation in horses. Units can be so sensitive that flexor tendon injuries can be detected before the horse develops clinical lameness. Thermography has been used to evaluate several dif...
Imaging diagnosis-caudal cruciate ligament avulsion in a horse. No abstract available.
Magnetic resonance imaging of the normal equine brain. 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, ...
Percutaneous ultrasound-guided pyelography aided diagnosis of ectopic ureter and hydronephrosis in a 3-week-old filly. Ultrasound-guided percutaneous pyelography has previously been used in dogs to diagnose ectopic ureter. To the authors' knowledge its use has never been reported in the horse. This paper reports the technique used in a three-week-old filly with a suspected ectopic ureter. Pyelography can be performed under sedation and is a relatively simple, safe procedure. The technique enables assessment of individual renal function through collection and analysis of urine from each renal pelvis.
Equine bone scintigraphic uptake patterns related to age, breed, and occupation. It is well known that skeletal scintigraphy is an imaging modality with high sensitivity but low specificity. Sites of IRU provide good evidence of increased bone turnover but not its specific cause. Results of lameness workups, blocks, and other imaging techniques are required to determine specific causes. Overinterpretation of causes of IRU is tempting, especially in assigning diagnoses to EIBR--adaptive or non-adaptive. Nevertheless, a quarter of a century's experience with equine skeletal scintigraphy has shown that certain patterns and locations can be fairly predictive of certain patholo...
Computed tomography and magnetic resonance imaging of the equine head. Horses are frequently presented with clinical conditions warranting diagnostic imaging of the head. Unfortunately, evaluation of the equine head can be difficult using conventional radiography. The anatomic complexity and superimposition of the osseous, dental, and soft tissue structures complicate radiographic interpretation and diagnoses. Multiple radiographic projections may be necessary to image specific regions, and side-to-side comparison is often essential.
Equine nuclear scintigraphy. Indications, uses, and techniques. The demand for advanced and correlative imaging methods in equine medicine is growing. Scintigraphy can provide unique information about the physiologic status of an animal that cannot be discerned by other imaging modalities.
Computed radiography. CR is a useful tool for the equine veterinarian and has many advantages. Its only major disadvantage is the initial cost, in dollars and time, for setup in one's practice. CR is already in use at several universities and private practices in the United States and around the world. In the future, as is the case with any computer-based technology, this modality should become more affordable and readily available to smaller practices. The potential of CR in veterinary medicine combined with saturation of the human market is driving the development of specialized software and algorithms for veteri...
Diagnostic thermography. Thermography is a practical aid in the clinical evaluation of the equine patient. It is particularly germane to the evaluation of lameness. This modality specifically increases the accuracy of diagnosis. Thermography is the pictorial representation of skin temperature. The technique involves the detection of infrared radiation, which can be directly correlated to blood flow. To be accurate, thermography must be performed in a controlled area free of drafts. The area should be protected from sunlight to avoid erroneous heating of the skin, and the horse's hair length should be uniform. Thermogr...
Computed tomography and magnetic resonance imaging of the equine musculoskeletal conditions. There is a growing interest in the use of computed tomography (CT) and magnetic resonance (MR) imaging in equine orthopedic patients. It is well established that CT and MR imaging offer superior diagnostic information in a wide variety of musculoskeletal injuries in human beings and small animals. The highly detailed cross-sectional images obtained with these two modalities can often demonstrate pathologic changes undetected with other common imaging techniques. Based on their multiple applications in human beings and small animals, CT or MR imaging may prove to be the optimal diagnostic imagi...