In various domestic mammals, smaller breeds tend to have proportionally larger teeth, whereas this is not a universal trend across mammals. This suggests that body size can evolve faster than tooth size, leading to the prediction that tooth-body size scaling differs among closely related versus distant taxa. Here, we test this pattern in a new computed tomography (CT)Skriffer Utgitt au det Norske Vidensk-Akad scan dataset on 302 adult domestic rabbits of various breeds (maxilla and mandible) and compare this to 198 literature data from 20 nondomestic lagomorph species (maxilla only). Skull or mandible length served as body size proxies. The allometric scaling of the length of the cheek tooth row and the diastema, as well as the jaw width, with these proxies and with each other was investigated. In domestic rabbits, there is a negative allometric scaling between tooth row length and body size, that is, smaller animals have relatively larger teeth. Similar patterns appear within some wild lagomorph species, while across species, tooth row length and body size scale isometrically. These findings add to reports on allometric growth in domestic species. As the seeming advantage of disproportionately more chewing surface in smaller species is apparently lost over time, the postulate of an optimal tooth row size for an organismal design emerges, for which there is currently no theory. Possibly, veterinary experiences that dental problems are particularly frequent in small domestic breeds with relatively larger teeth might provide leverage for such a concept. Studies on the physiological effects of differences in relative tooth size between breeds are warranted.

This study described, assessed and correlated ultrasonographic, computed tomographic, and histological findings in the sacroiliac joints of adult Warmblood horse cadavers. In total, 25 joints from 15 horses were examined post-mortem using transrectal ultrasonography and helical computed tomography. Findings on computed tomography were graded in the caudal joint third (caudally) and for the entire joint as mild, moderate, or severe. In total, 11 joints from nine horses were evaluated histologically. All joints (100%) showed abnormalities on computed tomography, and 92% (23/25) displayed abnormal ultrasonographic findings. The most common ultrasonographic findings were osteophytes (92%), joint effusion (76%), and sacral/iliac bone modeling (76%). Computed tomography revealed osteophytes (92% caudally, 100% overall), sclerosis (72% caudally, 88% overall), subchondral bone lesions (60% caudally, 88% overall), and enthesophytes (60% caudally, 68% overall). The most severe CT findings occurred caudally (44%), whereas 24% occurred cranially,16% in the mid portion of the SIJ, and 16% were multifocally present in the SIJ Histological analysis showed degenerative changes in the cartilage, subchondral bone, and the joint capsule. Horses with more pronounced imaging abnormalities also showed corresponding histological degeneration. Significant correlations were found between computed tomographic findings caudally and in the entire joint (rs = 0.915, p < 0.001, n = 25), and between imaging and histological findings (computed tomography: rs = 0.731, p = 0.011, n = 11; ultrasonography: rs = 0.67, p = 0.024, n = 11). Non-significant correlations were observed between mean ultrasonographic and computed-tomographic grades (rs = 0.35, p = 0.087, n = 25). Findings suggest these structural changes may reflect adaptation to joint loading. Transrectal ultrasonography appears suitable as a first-line diagnostic tool. However, future studies are essential to compare the diagnostic imaging findings of SIJs in asymptomatic and symptomatic horses to elucidate their clinical relevance.

The objective of the present study was to compare the diagnostic performance of radiography to computed tomography (CT) for the diagnosis of distal tarsal osteoarthritis. All images were interpreted and scored by 2 evaluators until a consensus was reached; they were blinded to the history, final imaging diagnosis, and results of the corresponding radiographic or CT study. On radiographs and CT images of 54 tarsi, 6 criteria (osteophyte/enthesophyte height, small/large subchondral bone radiolucencies, subchondral bone thickness, joint space narrowing) were scored in the proximal intertarsal (PIJ), distal intertarsal (DIJ), and tarsometatarsal joint (TMTJ). Compared to CT, mean radiographic scores were significantly lower for 1. small and large subchondral bone radiolucencies in all joints (p < 0.001–0.03); 2. subchondral bone thickness in the PIJ and DIJ (p = 0.03 and 0.005); and 3. enthesophyte and joint space narrowing score in the DIJ (p = 0.04 and 0.002). Low-to-high positive predictive values (PPV) were calculated for the individual criteria in all joints (0–100%). For the sum of scores of all criteria in the PIJ, DIJ, or TMTJ, respectively, PPVs were high (94–98%). In conclusion, radiography is a useful screening tool provided multiple criteria are assessed. However, CT offers significant advantages for the diagnosis of distal tarsal OA.

Single-source dual energy (SSDECT) and detector-based spectral computed tomography (DBSCT) are emerging technologies allowing the interrogation of materials that have different attenuation properties at different energies. Both technologies enable the calculation of effective atomic number (EAN), an index to determine tissue composition, and electron density (ED), which is assumed to be associated with cellularity in tissues. In the present prospective observational study, EAN and ED values were determined for 16 zones in normal subchondral and trabecular bone of 37 equine cadaver limbs. Using both technologies, the following findings were obtained: 1. palmar/plantar EAN zone values in the fetlock increased significantly with increasing age of the horse; 2. all EAN and ED values were significantly lower in the trabecular bone than in the subchondral bone of all phalanges; 3. in the distal phalanx and navicular bone, most EAN and ED values were significantly lower compared to the proximal and middle phalanx; and 4. some EAN and ED values were significantly different between front and hind limbs. Several EAN and ED values significantly differed between SSDECT and DBSCT. The reported EAN and ED values in the subchondral and trabecular bone of the equine distal limb may serve as preliminary reference values and aid future evaluation and classification of diseases.

SummaryA 22‐year‐old donkey (Equus asinus) mare was presented for investigation of a 3‐day history of lethargy and anorexia. Serum biochemistry profile revealed severe increased liver‐derived enzymes. Abdominal ultrasound demonstrated several large round cysts in the liver. Broad‐spectrum antimicrobials and anti‐inflammatory therapy were started. However, exacerbation of the clinical signs occurred, and the donkey was euthanised. Necropsy and histopathological evaluation showed multiple hydatid cysts with protoscoleces from Echinocococcus spp. in the liver with replacement of parenchyma by fibrosis accompanied by liver atrophy, severe ascites and thorax effusion. The present report describes the first case of a molecularly confirmed Echinococcus equinus infection in a donkey in northern Switzerland.

Ex situ breeding constitutes an important tool for species conservation; however, many reptile species are not managed sustainably under human care due to poor fecundity in ex situ settings. In this study, we tested whether the translocation of a seasonally reproducing species to a different environment results in decoupling of extrinsic signals and intrinsic conditions. The endocrinological patterns of plasma steroid sex hormones, follicular development, and mating behaviour of two female and two male sexually mature Aldabra tortoises (Aldabrachelys gigantea) in a zoological institution in the Northern hemisphere was aligned with enclosure climate data (mean monthly daylight duration, temperature, and precipitation) and compared with respective hormone patterns of wild individuals and climate conditions in the native habitat on the Aldabra Atoll in the Southern hemisphere. Whereas occurrence of mating behaviour was not considered a limiting factor, lack of ovulation and subsequent follicular atresia was the main reason for the lack of reproductive output. While it was impossible to elucidate the triggering factors of ovulation and the multifactorial complexity of reproduction was not fully addressed, this study indicates suboptimal temperature conditions and relative temporal shifts of interacting external triggers (temperature and photoperiod) in the zoo setting.

Complete resection is a key prognostic factor for survival in patients with soft tissue sarcoma (STS), in humas and companion animals alike. Fluorescence-guided surgery could improve resection accuracy. As dogs are frequently affected by STS, they serve as a model to test an anti-αvβ3 integrin targeting near-infrared fluorescent (NIRF) dye (AngiostampTM800) for fluorescence-guided surgery in STS to evaluate its safety and feasibility in dogs, and if it translates into a clinically relevant benefit compared to the standard of care with regards to completeness of surgery and local recurrence. Furthermore, we aimed to correlate target expression and NIRF-signal intensity. Twenty dogs with STS were randomly allocated to either receive Angiostamp™ (NIRF group) or physiologic saline (control group) preoperatively. The researchers were blinded for treatment, and resections were adapted based on the NIRF-signal, if needed. Margin status was histologically determined at the 1 and 3 cm margin. The tumor-to-background ratio was measured in native tissue biopsies and formalin-fixed tissue. The fluorescent area was compared to the corresponding tumor areas as confirmed by histology using the Dice coefficient. Target expression was quantified by immunohistochemistry and correlated to NIRF-signal ratios. A fluorescent signal was detected in all 10 tumors of the NIRF group, with a tumor-to-background ratio of 7.4 ± 5.8 in native biopsies and 13.5 ± 10.9 in formalin-fixed tissue. In the NIRF group, resection margins were adapted in 5/10 cases, leading to complete resection and preventing R1 in four of these cases. In the NIRF and control group 9/10 and 8/10 resections were R0, with one local recurrence in each group and one sarcoma-related death in the NIRF group. The NIRF-signal correlated with the histologically confirmed tumor area (Dice coefficient 0.75 ± 0.17). Target expression was higher in tumor compared to peritumoral tissue (p < 0.0003) and showed a moderate correlation with the NIRF-signal (r = 0.6516, p < 0.0001). Fluorescence-guided surgery using Angiostamp™ can pinpoint residual disease in the tumor bed and contributes to an improved resection accuracy in canine STS.

Computed tomography (CT) has become a routine method to examine the equine skull.Its clinical use for the diagnosis of diseases of the incisors and canine teeth has not been reported so far.The goal of this study was to study the prevalence and relationship of single CT features and equine odontoclastic tooth resorption and hypercementosis (EOTRH) in equine incisors and canine teeth.In this descriptive retrospective study, helical CT studies of 115 Warmblood horses of the age of 5 years or older examined between 2007 and 2020 for reasons unrelated to the incisors and canine teeth were included.Resorption in the crown or root, hypercementosis, widening of the periodontal space, clubbing of the root, lysis of the lamina dura, an abnormal pulp cavity and fracture of the root were recorded in all incisors and canine teeth.The length of the pulp cavity and the labial and lingual/palatal length of the enamel and root was measured in each incisor and canine tooth.Additionally, the angulation was assessed in each incisor.The variable EOTRH was defined based on the presence of resorptive lesions, hypercementosis and clubbing.In result median age of the included horses was 12 years (range, 5-29 years).With regard to the investigated population of horses, 44.3 % of all horses had normal incisors whereas 55.7 % of the horses had mild EOTRH changes in one incisor at least.Regarding the canine teeth, 54.7 % of the horses had normal canine teeth whereas 43.3 % horses had mild EOTRH in one canine tooth at least.With regard to all investigated teeth, 868 teeth (53.0 %) were classified as normal, whereas 769 incisors and canine teeth (47.0 %) showed at least one abnormal CT criterion.Clubbing of the root and hypercementosis were most common (37.1 % and 22.7 %, respectively) and EOTRH was present in 27.1 % of all teeth.Mild changes were more common than moderate or severe abnormalities.In the lower jaw, hypercementosis and widening of the periodontal space at the anatomical root and apex of the root was significantly more frequent (p = 0.004 and 0.02), whereas clubbing of the root was more common in the upper jaw (p = 0.009).In canine teeth, resorption in the anatomical crown and anatomical root, widening of the periodontal space, clubbing and lysis of the lamina dura were significantly more common whereas hypercementosis was more common in incisors (p < 0.001).Frequency of certain CT changes significantly increased from central to middle and corner incisors.Severity of all single CT criteria as well as prevalence and severity of EOTRH significantly increased with age (r = 0.08-0.56).Linear forward and backward multivariate regression analysis confirmed a significant association between prevalence and severity of EOTRH and age, changes of the pulp cavity, widening of the periodontal space at the anatomical rootand incisor group (central, middle, corner) (p = 0.01 -< 0.001).In conclusion computed tomographic changes of the incisors and canine teeth are common and age-related in Warmblood horses.Therefore, treatment of EOTRH should not be based on diagnostic imaging alone, but always in combination with a thorough clinical examination.

Tenosynovitis of the digital flexor tendon sheath (DFTS) is diagnosed using ultrasonography and contrast tenography. Nevertheless, making a precise preoperative diagnosis is challenging. This study aimed to determine and compare the sensitivity and specificity of low-field MRI and MRI tenography (MRIt) to detect artificially created soft-tissue lesions in the DFTS. In 21 DFTSs, 118 lesions were made tenoscopically in the superficial digital flexor tendon (SDFT), deep digital flexor tendon (DDFT), manica flexoria (MF) and proximal scutum. MRI and MRI, following intrathecal gadolinium administration (MRIt), were performed. The sensitivity and specificity of MRI and MRIt were calculated and compared. Proximal scutum lesions were less frequently identified by MRI (Sensitivity 38%, specificity 96%) compared to MRIt (Sensitivity: 50%, p = 0.80; specificity: 96%, p = 1). This was similar for SDFT lesions (Sensitivity: 39% versus 54%, p = 0.72; specificity: 93% versus 96%, p = 1). MRI detected DDFT lesions (sensitivity 34%; specificity 100%) better than MRIt (sensitivity 32%, p = 0.77; specificity 98%, p = 1). This was similar for MF lesions (MRI sensitivity 61%; specificity 100% vs. MRIt sensitivity 50%, p = 0.68; specificity 96%, p = 1). Lesion size was significantly associated with MRI or MRIt diagnosis (p = 0.001). The intrathecal administration of gadolinium did not significantly improve the ability of low-field MRI to diagnose artificial DFTS tendon lesions. Small lesion length was a significant discriminating factor for lesion detection. MRI and MRIt specificity were high, thus being helpful in diagnosing an intact structure.

SummaryBackgroundA common cause of lameness in horses is tenovaginitis of the digital flexor tendon sheath (DFTS). Ultrasound and contrast tenography have become frequently used diagnostic tools for abnormalities in the DFTS, but are considered insufficiently accurate in describing specific lesions.ObjectivesTo determine the sensitivity and specificity of computed tomographic tenography (CTT) and 3 Tesla magnetic resonance imaging (MRI) to detect artificial lesions within the DFTS.Study designBlinded laboratory study.MethodsUsing an arthroscopic hook knife, lesions (10–20 mm long and 3–5 mm deep; n = 52) were created tenoscopically in the superficial digital flexor tendon (SDFT), deep digital flexor tendon (DDFT), manica flexoria (MF) and proximal scutum in 19 distal limb specimens. MRI and CTT were performed and images were reviewed. Sensitivity and specificity were calculated for each modality and compared.ResultsComputed tomographic tenography and MRI identification of SDFT and MF lesions showed similar sensitivity (75% vs. 85%, respectively; p = 1) and specificity for MF lesions (96% for both). SDFT lesions specificity was similar for CTT versus MRI (85% vs. 77%, respectively; p = 0.88). For DDFT lesions, MRI sensitivity (62%) was higher compared to CTT (38%), although not statistically significant (p = 0.58). MRI specificity (92%) was lower than CTT (96%, p = 1). Lesions in the proximal scutum were more frequently identified by MRI compared to CTT (sensitivity: 93% vs. 57%, p = 0.17; specificity: 96% vs. 100%, p = 1).Main limitationsArtificial, small lesions were assessed. An incomplete arthroscopic portal seal resulted in pressure loss and contrast leakage.ConclusionsThe sensitivity and specificity of both modalities are good to excellent for the diagnosis of most artificially created lesions. CTT performed similarly to MRI in detecting SDFT and MF lesions. MRI showed a higher sensitivity for the diagnosis of DDFT and proximal scutum lesions. The results indicate a future application of CTT for the diagnosis of DFTS pathologies, whenever suspecting MF tears.

The objective of this study was to investigate the feasibility of external jugular vein catheterization through an ear vein in piglets. Forty-six sevoflurane-midazolam anaesthetized piglets were included. External jugular vein catheterization was conducted through the ear vein using the Seldinger technique. Part 1 (n = 27): optimal puncture site was based on the deltoid tuberosity as a landmark to reach the external jugular vein. The final position of the catheter was verified in 25 piglets using computer tomography. Catheterization time was recorded and patency of the catheter assessed by repeated blood sampling for up to 4 h. Part 2 (n = 19): ear vein catheterization was without taking into account any landmarks. Functionality for blood sampling was evaluated as described in part 1. Catheter advancement was possible in 25/27 and 18/19 piglets in parts 1 and 2, respectively. Median (range) time required for successful catheterization was 1.95 (1-10) min (n = 38). The deltoid tuberosity was a good landmark to reach the external jugular vein. But blood sampling was also possible through catheters ending slightly cranial to the external jugular vein. Despite successful catheter advancement, blood sampling was not possible from one catheter in each part of the study (total: two piglets). One of these catheters presented luminal damage, while the other one presented as normal after being removed from the animal. Summarizing, central vein catheterization through the ear vein was feasible in 93.5% and repeated blood sampling was possible in 89.1% of the piglets (n = 46).

Open splint bone fractures are at increased risk of osteomyelitis and/or sequestrum formation. Infection is not always restricted to bony structures but may also affect the surrounding ligamentous structures including the interosseous ligament. This case series describes 5 horses with infection of the metacarpal interosseus space, including the metacarpal interosseus ligament, as a complication of an open fracture of the fourth metacarpal bone. All described horses had been presented to the equine department, Vetsuisse Faculty, University of Zurich, between July 2017 and October 2021 and fulfilled the following criteria: radiographic diagnosis of an acute fracture of second metacarpal (MCII)/metatarsal bone (MTII) or the fourth metacarpal (MCIV)/metatarsal bone (MTIV); the fracture was classified as open because of a wound in the affected metacarpal/metatarsal region; the presence of radiographic signs of osteomyelitis in the interosseus metacarpal/metatarsal space. Five horses fulfilled the inclusion criteria, and all had an open fracture of MCIV. Lameness at the walk varied from mild to severe. Wound secretion was present in 3 of the 5 horses. Radiography was done in all 5 cases and computed tomography was also used in 4 cases. Three different surgical treatments combined with antibiotics and nonsteroidal anti-inflammatory drugs were used: bone curettage, partial ostectomy and segmental ostectomy. All 5 cases made a complete recovery and returned to their intended use within 2.5 months to 2 years after surgery. In horses with persistent lameness and/or persistent wound secretion as a consequence of an open splint bone fracture, the adjacent metacarpal interosseus space should be assessed. Computed tomography appears superior to radiography for the presurgical staging of osteomyelitis because of its higher spatial and contrast resolution. The prognosis after extensive surgical and medical treatment appears to be good.

Diagnostic imaging is a mainstay in the investigation of equine neck and back pain, but interpretation of radiographic and ultrasonographic findings in the spinal column of horses is not straightforward for a variety of reasons including individual anatomical variations, progressive degenerative nature of most pathologies and superimposition as well as technical limits.These issues are even more relevant in the context of examinations of apparently sound horses with absent, mild or unclear complaints, like it is often the case in pre-purchase examinations or cases of failure to meet expected performance.The first aim was to report on the spectrum, degree and location of first-line imaging findings in the spine of a large population of normally performing horses.Limited data is available about agreement of interpretation of equine vertebral column imaging by radiologists.The second aim of this prospective study was to determine interobserver agreement on radiographic and ultrasonographic diagnostic imaging findings in the vertebral column of the same population between multiple observers with longstanding experience in equine diagnostic imaging at two different institutions.Seventy-one horses randomly selected from a larger population of 250 normally performing horses participating in a swiss project on equine back health were examined at one referral center.Radiographic and ultrasonographic examinations were performed in a standardized fashion and images graded separately by two experienced radiologists at two different institutions.Focus was placed on osteoarthrosis of the synovial intervertebral articulations (SIVAs), impinging and overriding of the spinous processes (SPs) and spondylosis.Cohen's weighted kappa was calculated for each pathology, location and segment in each modality.Interobserver agreement was calculated for findings at specific locations, single pathologies and single grades.Most horses showed no changes and were allocated grades 0 at most locations.Few abnormalities were found throughout the vertebral column, with clusters of abnormalities of the SIVAs in the caudal cervical segment and cranial lumbar segment as well as a cumulation of changes at the dorsal spinous processes in the caudal thoracic segment.These coincide with previously reported predilection sites of imaging findings in symptomatic populations.Overall mean value of agreement for imaging findings was moderate (k= 0.7).Agreement was moderate for imaging findings regarding the synovial intervertebral articulations of the thoracolumbar spine in radiography (k=0.66)but weak in ultrasonography (k=0.58).There was moderate agreement in the imaging findings of the cervical spine in ultrasonography (k=0.61) as well as radiography (k=0.62).Strong agreement was found in the radiographic assessment of changes of the thoracolumbar spinous processes (k=0.80).Almost perfect agreement was found in the radiographic assessment of thoracolumbar spondylosis (k=0.95).Agreement between radiologists in detection and grading of pathologies of the equine vertebral column is weak to almost perfect depending on pathology and location.Our results confirm findings about distribution of specific pathologies found in other studies and support the importance of interpreting imaging findings along with clinical findings for definitive case management and decision making.Additional studies are needed for determination of the correlation of imaging findings among different modalities and correlation of diagnostic imaging with clinical findings.

OBJECTIVE To determine morphological characteristics of subchondral cystic lesions (SCLs) in the proximal phalanx (PP) of adult horses. SAMPLE Radiographs and/or CT scans of PP from 46 horses. PROCEDURES 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 associated with short, incomplete fractures, while 30 of the proximal PP SCLs (69.7%) were found mid sagittal. Proximal SCLs mostly showed a blurred, irregular shape (62.8%) and long, as well as wide, but shallow shapes in CT. Eighteen SCLs (29.5%) were found in the distal PP, near the proximal interphalangeal joint (group B). In contrast to the described proximal SCLs, the distal SCLs were of circular or oval shape, well delineated (77.8%), and distinctly larger. Horses of group A were significantly older (mean age, 11.47 years) than horses of group B (mean age, 6.72 years). CLINICAL RELEVANCE The distribution and morphological attributes of proximal PP SCLs as well as their association to subchondral bone lesions and short, incomplete proximal fractures indicate more recently developed lesions due to chronic stress factors, such as repetitive trauma to the cartilage and subchondral bone. In contrast, morphology and distribution of distal SCLs showed high accordance with developmental bone cysts originating from a failure of endochondral ossification.

BACKGROUND:Advances in MRI coil technology and increased availability of high-field MRI in veterinary medicine enable the acquisition of images of increasingly high spatial resolution while preserving signal-to-noise ratio.The purpose of the present study was to compare 3T high-resolution magnetic resonance imaging (HR-MRI) with ultrasound (US) and ultrasound biomicroscopy (UBM) in the normal canine eye, to assess its potential to depict normal ocular anatomy.RESULTS:HR-MRI was compared with US and UBM in 10 eyes from 10 healthy beagle dogs. Ocular structures (cornea, anterior chamber, iridocorneal angle, iris, lens, ciliary body, choroid, vitreous body, posterior wall of the eye, optic nerve and optic nerve sheath, extraocular muscles) were assessed subjectively and central corneal thickness (CCT), anterior chamber depth (ACD), aqueous depth (AQD), anteroposterior, mediolateral and dorsoventral lens diameter (APLD, MLLD, DVLD), anteroposterior diameter of the globe including and excluding the scleroretinal rim (APDSRR, APD), vitreous chamber depth (VCD) and optic nerve sheath diameter (ONSD) were measured in HR-MRI and in US. Optic nerve diameter (OND) was measured in HR-MRI. HR-MRI and UBM appearance of the anterior segment were subjectively compared. Detailed reference high-resolution MRI images of normal eyes of Beagle dogs are provided.CONCLUSIONS:HR-MRI allowed assessment of all structures identified with US and UBM. The MRI examinations were performed under general anesthesia with the addition of a neuromuscular blocking agent, while US and UBM examinations were performed in conscious animals. Visibility of the entire ocular wall, the lens, the structures caudal to the ciliary body and the optic nerve and its sheath was superior with HR-MRI. HR-MRI allowed the distinction of retina, choroid and sclera, and the delineation of structures not previously identified in canine eyes with MRI, including Tenon's capsule and the sub-Tenon's space.Plane selection was more accurate with HR-MRI compared to US. In general, the range of measurements was narrower for MRI than for US. CCT, AQD, APLD, MLLD, APD, APDSRR and ONSD differed significantly between HR-MRI and US, respectively (p = 0.005-0.027).Micro-MRI may be useful for the assessment of ocular pathologies in the future.

OBJECTIVE To determine the diagnostic performance of computed tomographic arthrography (CTA) and 3 Tesla magnetic resonance imaging (MRI) for detecting artificial meniscal, meniscotibial ligament (MTL) lesions and cruciate ligament (CL) lesions in horses. STUDY DESIGN Ex vivo controlled laboratory study. ANIMALS Nineteen stifles from adult horses. METHODS Stablike defects (n = 84) (16 mm long, 10 mm deep) were created in the menisci (n = 35), CLs (n = 24), and MTLs (n = 25) via arthroscopy prior to MRI and CTA (80 mL contrast at 85 mg/mL per joint). Two radiologists, unaware of the lesions, reached a consensus regarding the presence of lesions, based on 2 reviews of each study. Sensitivity and specificity of MRI and CTA were determined using arthroscopy as a reference and compared with McNemar's tests. RESULTS The sensitivity and specificity of MRI (41% and 86% respectively) and CTA (32% and 90% respectively) did not differ (P = .65). The sensitivity (MRI: 24%-50%; CTA:19%-40%) and specificity (MRI: 75%-92%; CTA 75%-100%) of imaging modalities did not differ when detecting lesions of the menisci, MTLs, and CLs (P = .1-1.0). The highest sensitivities were achieved when MTLs were evaluated with MRI (50%) and CLs with both modalities (40%). CONCLUSIONS The diagnostic performance of CTA was comparable with that of MRI, with a low to moderate sensitivity and high specificity. CLINICAL SIGNIFICANCE Computed tomographic arthrography should be considered as an adjunct to diagnose CL injuries. This is important for equine clinicians, as the CL cannot be visualized adequately using basic imaging techniques preoperatively.

Radiosynoviorthesis (RSO) is a decades known, effective intra-articular nuclear medicine local therapy, with few rare side-effects, in which inflamed synovial membrane is treated by means of colloidal beta-emitters. There are major variations worldwide in terms of acceptance, frequency of use and approved indications for this procedure. Thus, reliable figures that reflect reality are only available for a few countries. A Europe-wide survey revealed that RSO is carried out most frequently in Germany, where RSO is the most common nuclear medicine therapy with about 70,000 joints treated per year. The main indications include synovitis due to rheumatoid arthritis, hemophilia and pigmented villonodular synovitis (PVNS), and depending on national approvals, osteoarthritis. Despite the many indications, there are very few published scientific studies and therefore, RSO evidence is lacking. Reliable data on the clinical usage of RSO and demographics of RSO specialists are only available in Germany, thus we discuss the future challenges of RSO mainly from a German perspective. In the German healthcare system, RSO is performed primarily on an outpatient basis and plays only a minor role in the university setting. The necessary expertise for RSO is therefore lacking, for the most part, at university training centers. Currently, nearly more than three quarters of the German RSO experts are over fifty years old, illustrating a shortage of young talent. In the future, RSO providers from the non-university or private sector will have to cooperate with universities through networks and will have to intensify their cooperation with referring physicians, such as rheumatologist and orthopedic surgeons, and patients in order to maintain a timely and beneficial exchange of information. In networks of RSO experts, the participants must jointly develop and establish training concepts and facilities for future talents, elaborate on guidelines, if clinically useful expand the range of indications, initiate studies to generate further evidence and finally make the procedure more public. In addition, it is worthwhile to apply this process beyond human medicine to other fields, such as medical physics and veterinary medicine. If these points are implemented, the future of RSO will be bright, if it fails, it looks bleak.

Summary This study reports the use of parathyroid hormone fragment peptide 1‐34 (PTH 1‐34 ) cross‐linked to a hydrogel in a fibrin base for the treatment of subchondral cyst‐like lesions (SCLs). The objectives were to determine the clinical and radiographic outcome of 28 horses with lameness attributable to one or two SCLs treated locally with one of three different concentrations of PTH 1‐34 and to identify which concentration produces the best results. Twenty‐eight horses (34 SCLs) were treated surgically by debriding the content of the SCL and injecting different concentrations (0.1, 0.4, or 1 mg/mL) of PTH 1‐34 in a fibrin hydrogel into the cavity. Treatment was considered successful if the horse was sound 12 months after treatment. The mean age of the horses was 7.2 years. Treatment was successful in 22 (78.6%) horses and improved the radiographic appearance of 27 (79.4%) SCLs. The outcome was not affected by age of the horse or by the number of SCLs (1 or 2) per horse. PTH 1‐34 in a fibrin hydrogel administered into the SCL after surgical debridement of the lesion appears to be an effective treatment for horses with one or two SCLs. A PTH 1‐34 concentration of 0.4 mg/mL may be slightly superior to concentrations of 0.1 and 1.0 mg/mL in resolving SCLs.

Summary The objective of this study was to investigate the distribution pattern of two different volumes of a mepivacaine 2%/iopromide mixture along the infraorbital nerve using a controlled injection pressure. Infraorbital nerve blocks were performed at the infraorbital foramen with two different volumes (group 10: 10 mL or group 15: 15 mL) using a 22 gauge, 3 cm long needle and a standardised injection pressure in 10 cadaver skulls. Ten minutes after injection, computed tomography was performed in all skulls. Images were analysed for needle position, length of the iopromide column, filling percentage of the infraorbital canal, presence of iopromide at the maxillary foramen, volume of leakage, length and angle of the infraorbital canal and pathological changes. Percentage of infraorbital canal filling ranged from 74% ± 0.23 to 86.9% ± 0.24 and iopromide was present at the maxillary foramen in 70–90% of the blocks of groups 15 and 10 respectively; neither variables differed significantly between groups 15 and 10 (P = 0.582 and P = 0.244 respectively). Mean leakage retrograde into the rostrally surrounding tissue and into the maxillary sinus was significantly greater in group 15 (7.9 cm 3 ± 4.2) than group 10 (3.02 cm 3 ± 3.13), P = 0.008. Older horses were significantly associated with higher filling percentages (P = 0.049), whereas filling percentages or whether the mixture reached the maxillary foramen were not associated with any of the other variables. Infraorbital nerve blocks using 10 and 15 mL result in complete filling of the infraorbital canal in the majority of horses. This block may result in sufficient analgesia of Triadans 06 to 11 and offer a suitable safe alternative to maxillary nerve blocks.

Traumatic reticuloperitonitis (TRP) in cattle is caused by ingested nails, pieces of wire, and other nonmetallic materials that injure the reticular wall. Clinical signs of acute TRP may include anorexia, fever, drop in milk production, rumen atony and tympany, abdominal pain, an arched back, a tucked up and "guarded" abdomen and spontaneous grunting, but may be obscure or absent in chronic cases. Haematological findings alone are not diagnostic, but total and differential white blood cell counts, the concentration of fibrinogen and total protein and the glutaraldehyde coagulation time may indicate inflammation associated with TRP. The clinical examination is aimed at eliciting a grunt in response to foreign body tests such as back grip, pole test or pain percussion. Inflammatory changes of the reticulum and adjacent organs and impairment of reticular motility are characteristic features of TRP and can be detected via ultrasonography. Radiography is the technique of choice for the visualisation of metallic foreign bodies and for monitoring the efficacy of a magnet. Treatment may be conservative or surgical, but in most cases initial treatment is conservative with administration of a magnet and antibiotics. If the cow fails to respond to medical treatment, surgical treatment is the next option other than euthanasia and ideally is carried out after imaging of the reticulum. If this is not feasible, a second magnet and continuation of antibiotic treatment is recommended. (C) 2020 Elsevier Ltd. All rights reserved.