Elke Van der Vekens

Computed tomographic anatomy of the equine stifle joint.

OBJECTIVE To provide a detailed computed tomography (CT) reference of the anatomically normal equine stifle joint. Sample-16 hind limbs from 8 equine cadavers; no horses had evidence of orthopedic disease of the stifle joints. PROCEDURES CT of the stifle joint was performed on 8 hind limbs. In all limbs, CT was also performed after intra-articular injection of 60 mL of contrast material (150 mg of iodine/mL) in the lateral and medial compartments of the femorotibial joint and 80 mL of contrast material in the femoropatellar joint (CT arthrography). Reformatted CT images in the transverse, parasagittal, and dorsal plane were matched with corresponding anatomic slices of the 8 remaining limbs. RESULTS The femur, tibia, and patella were clearly visible. The patellar ligaments, common origin of the tendinous portions of the long digital extensor muscle and peroneus tertius muscle, collateral ligaments, tendinous portion of the popliteus muscle, and cranial and caudal cruciate ligaments could also be consistently evaluated. The cruciate ligaments and the meniscotibial ligaments could be completely assessed in the arthrogram sequences. Margins of the meniscofemoral ligament and the lateral and medial femoropatellar ligaments were difficult to visualize on the precontrast and postcontrast images. CONCLUSIONS AND CLINICAL RELEVANCE CT and CT arthrography were used to accurately identify and characterize osseous and soft tissue structures of the equine stifle joint. This technique may be of value when results from other diagnostic imaging techniques are inconclusive. The images provided will serve as a CT reference for the equine stifle joint.

Comparison of cross-sectional anatomy and computed tomography of the tarsus in horses.

OBJECTIVE To compare computed tomography (CT) images of equine tarsi with cross-sectional anatomic slices and evaluate the potential of CT for imaging pathological tarsal changes in horses. SAMPLE 6 anatomically normal equine cadaveric hind limbs and 4 tarsi with pathological changes. PROCEDURES Precontrast CT was performed on 3 equine tarsi; sagittal and dorsal reconstructions were made. In all limbs, postcontrast CT was performed after intra-articular contrast medium injection of the tarsocrural, centrodistal, and tarsometatarsal joints. Images were matched with corresponding anatomic slices. Four tarsi with pathological changes underwent CT examination. RESULTS The tibia, talus, calcaneus, and central, fused first and second, third, and fourth tarsal bones were clearly visualized as well as the long digital extensor, superficial digital flexor, lateral digital flexor (with tarsal flexor retinaculum), gastrocnemius, peroneus tertius, and tibialis cranialis tendons and the long plantar ligament. The lateral digital extensor, medial digital flexor, split peroneus tertius, and tibialis cranialis tendons and collateral ligaments could be located but not always clearly identified. Some small tarsal ligaments were identifiable, including plantar, medial, interosseus, and lateral talocalcaneal ligaments; interosseus talocentral, centrodistal, and tarsometatarsal ligaments; proximal and distal plantar ligaments; and talometatarsal ligament. Parts of the articular cartilage could be assessed on postcontrast images. Lesions were detected in the 4 tarsi with pathological changes. CONCLUSIONS AND CLINICAL RELEVANCE CT of the tarsus is recommended when radiography and ultrasonography are inconclusive and during preoperative planning for treatment of complex fractures. Images from this study can serve as a CT reference, and CT of pathological changes was useful.

TTA Rapid: Description of the Technique and Short Term Clinical Trial Results of the First 50 Cases

OBJECTIVE To (1) describe a modified technique for tibial tuberosity advancement (TTA) in dogs with cranial cruciate ligament (CCL) rupture and (2) report short term outcome and complications. STUDY DESIGN Prospective clinical study. ANIMALS Dogs with unilateral CCL rupture (n = 50). METHODS TTA was performed with a novel implant to achieve advancement of the tibial crest. The technical protocol, specific implants and instrumentation, and the short term outcome are described. RESULTS Various breeds (mean ± SD weight, 31.9 ± 13.3 kg) were included. Mean age at treatment was 64 ± 30.6 months. Minor complications occurred in 30% and major complications in 4% of the cases. Forty-eight (96%) dogs had a good to excellent outcome 3 months after surgery. CONCLUSION The modified technique is a viable alternative to other osteotomy techniques.

The effect of anesthesia with propofol and sedation with butorphanol on quantitative contrast-enhanced ultrasonography of the healthy feline kidney

Contrast-enhanced ultrasonography of the left kidney was performed using a commercial contrast agent in six healthy adult purpose-bred cats. A cross-over design was used to compare three protocols: (1) awake, (2) butorphanol (0.4 mg/kg IM), and (3) propofol (3.5-7.7 mg/kg IV boluses to effect). Time-intensity curves were created from two regions-of-interest drawn in the renal cortex. The curves were analyzed for blood flow parameters representing blood volume (base intensity, peak intensity, area-under-curve) and blood velocity (arrival time, time-to-peak, wash-in/out). There was no difference in the subjective enhancement pattern between the three protocols. No significant effect of butorphanol was observed in any of the perfusion parameters (P > 0.05). Propofol did not influence the most important perfusion parameter, area-under-the-curve, and is adequate for use in contrast-enhanced ultrasound studies.

Ultrasonographical examination of feline adrenal glands: intra- and inter-observer variability

Interpretation of ultrasonographical measurements requires an understanding of the source and the magnitude of variation. A substantial part of the variation can be attributed to the observer, the equipment or the animal. The aim of this study was to evaluate which adrenal gland measurement is the least variable within and between observers. Three experienced ultrasonographers examined six cats at three different times on the same day, more than 1 h apart, according to a strict scanning protocol. Seven ultrasonographical measurements were performed on each adrenal gland (maximal length on sagittal images, maximal height at the cranial and caudal poles on sagittal and transverse images, and maximal width of the cranial and caudal poles on transverse images). Height measurements in both planes showed the lowest variability within and between observers compared with length and width measurements. Descriptive ultrasonographical features, such as echogenicity of the gland, presence of hyperechoic spots or layering assessment, demonstrated satisfactory-to-good intra- and inter-observer agreement, whereas the shape assessment showed very poor inter-observer agreement. The results of this study describe a reliable scanning protocol that can be the basis for future adrenal ultrasonographical examinations for cats suspected of adrenal disease (eg, hyperaldosteronism, hyperadrenocorticism, sex hormone-producing tumours).

Intraobserver and interobserver agreement on the radiographical diagnosis of canine cranial cruciate ligament rupture

Even though radiography is one of the most frequently used imaging techniques for orthopaedic disorders, it has been demonstrated that the interpretation can vary between assessors. As such, the purpose of this study was to examine the intraobserver and interobserver agreement and the influence of level of expertise on the interpretation of radiographs of the stifle in dogs with and without cranial cruciate ligament rupture (CCLR). Sixteen observers, divided in four groups according to their level of experience, evaluated 30 radiographs (15 cases with CCLR and 15 control stifles) twice. Each observer was asked to evaluate joint effusion, presence and location of degenerative joint disease, joint instability and whether CCLR was present or absent. Overall, intraobserver and interobserver agreement ranged from fair to almost perfect with a trend towards increased agreement for more experienced observers. Additionally, it was found that stifles that were classified with high agreement have either overt disease characteristics or no disease characteristics at all, in comparison to the ones that are classified with a low agreement. Overall, the agreement on radiographic interpretation of CCLR was high, which is important, as it is the basis of a correct diagnosis and treatment.

B-mode and contrast-enhanced ultrasonography of the mammary gland during the estrous cycle of dogs

Pathology of the mammary gland is a common health issue in dogs and includes neoplasia, cysts, inflammation and infection. The use of the B-mode (US) and contrast-enhanced (CEUS) ultrasonography may aid in the diagnosis. Previous studies are currently lacking of the ultrasonic images of the mammary gland of healthy bitches in different stages of the estrous cycle and associated normal blood perfusion patterns. The purpose, therefore, was to describe the normal B-mode US and CEUS images of the mammary gland and inguinal lymph node, in six intact female beagles during five different stages of the estrous cycle (proestrus, estrus, early and late diestrus and anestrus). Within the same stage of the estrous cycle, the size (thickness) of the caudal mammary glands increased. During early and late diestrus, all mammary glands increased in thickness and had an increased heterogeneous B-mode ultrasonic appearance. The mammary glands had a heterogeneous, disorganized perfusion pattern when assessed using CEUS. For the cranial abdominal mammary gland, the area under the curve and the mean transit time increased between estrus and late diestrus and decreased between late diestrus and anestrus. For the inguinal mammary gland, only the time to peak was longer during the periods of anestrus compared to estrus whereas all the other contrast parameters did not change during the estrous cycle. In conclusion, hormonal influences cause major changes in the size, appearance and blood perfusion of mammary glands during the estrous cycle and should be considered when evaluating pathological changes of mammary glands.

Cat: The importance of a correct management and basic anaesthetic monitoring in a tension pneumothorax and tracheal foreign body

A six-year-old, male neutered, European domestic shorthair cat was presented at the emergency service of the Ghent University Small Animal Clinic with severe respiratory distress, subcutaneous emphysema and suspicion of an oesophageal foreign body reported by the referring veterinarian. After a radiographic study, a clinical examination suggested the presence of pneumothorax. Emergency thoracocentesis and thoracotomy were performed. Monitoring consisted of electrocardiography, capnography, pulse oximetry and non-invasive blood pressure. Sudden damping, followed by disappearance of the capnography curve was recorded during anaesthesia despite the use of intermittent positive pressure ventilation. A tracheal foreign body was found and removed. No macroscopic lesion in the trachea was found. After thoracic drain placement, the cat recovered uneventfully. A rapid, multidisciplinary approach is required when severe tension pneumothorax is present and standard anaesthetic monitoring tools are useful in detecting and solving early complications.

Ultrasonographic Findings in the Stifle Joint of Active Jumping andDressage Horses

Objective Ultrasonography (US) is frequently used to evaluate the equine stifle joint. Some soft tissue US findings are known to be clinically relevant, while others are considered incidental. These considerations are not always evidence-based. This study aims to describe the US findings observed in the stifle of clinically sound, active jumping and dressage horses. Design: Prospective study Animals: 46 Warmblood horses Procedures: To be included in this study, the horses had to fulfil 4 criteria: (1) in competition at least 1 time/month at national or international level, (2) in full work, (3) free of lameness, (4) no complains of the horse’s performances. Both stifle joints of each horse were scanned systematically by US and US findings were recorded. Results: 46 Warmblood horses fulfilled the criteria. US was normal in 21 horses, whereas abnormalities were detected in one or both stifles in 7 and 18 horses, respectively. Changes were seen in all compartments of the stifle joints: medial femorotibial joint (18 horses): osteophytes, effusion, subchondral cyst in the medial femoral condyle and lesions in the cranial meniscotibial ligament or medial collateral ligament; lateral femorotibial joint (4 horses): mild effusion, subchondral cyst in lateral femoral condyle; femoropatellar joint (16 horses): effusion, lesions in medial or intermediate patellar ligament or osteochondrotic lesions. Conclusion and Clinical relevance: Mild changes can be found ultrasonographically in the stifles of sport horses. Periarticular new bone formation was observed in 25% of the horses, apparently clinically not relevant. Lesions in the menisci, the tendinous portions of the popliteus muscle, long digital extensor muscle or peroneus tertius muscle or the lateral collateral ligament were not observed.

Ultrasonography of the Canine and Equine Stifle Joint - Correlation with Humans

The gross anatomy and physiology of the knee are similar in people, dogs and horses. However, evolution, way of life and the use of horses and dogs means that the detailed anatomy, physiology and disease processes have altered with time. In dogs, cranial cruciate ligament injury (30%), degenerative joint disease (17%) and patellar ligament injury (17%) are the most frequently encountered disease processes, while in horses, osteochondrosis and subchondral cysts (52%), medial collateral ligament injury (28%), patellar ligament injury (23%), degenerative joint disease (23%) and medial meniscus lesions (19%) are more frequently reported. In addition the technological possibilities and the cooperation of the patient are different between human and veterinary medicine. In people, ultrasonography of the knee is easy to perform and gives lots of information, but it has inferior diagnostic capabilities compared to MRI. In dogs, the small size of the joint and large variation between breeds are responsible for the limited use of knee ultrasonography. In horses, ultrasonography of the knee is risky and time-consuming but is currently the only practical alternative to radiography. There is a lack of ultrasonographic reference values in the dog and horse compared to people. Veterinary radiologists have to define normal variants and reference values in young and adult animals to improve the objectivity, and thus the quality, of knee ultrasonography.