Long-lasting hypoaldosteronism after adrenalectomy in a cat with hyperaldosteronism.

Case summary: A 10-year-old neutered male domestic shorthair cat was presented with an abdominal mass, associated renal failure, chronic vomiting, anorexia and progressive polyuria/polydipsia lasting for 3 weeks. Clinical examination and initial blood work revealed azotaemia, hypokalaemia and hypertension. Abdominal ultrasound showed an adrenal mass with a diameter of 3 cm near the right kidney. High serum aldosterone suggested primary hyperaldosteronism. Surgery enabled identification of the mass and its excision along with the right adrenal gland. Histologically, carcinoma of the adrenal cortex was diagnosed. Postoperatively, an increase in serum creatinine and potassium, along with a low serum aldosterone, led to a diagnosis of hypoaldosteronism. Mineralocorticoid therapy for 6 months was necessary, resulting in clinical and biological improvement. Relevance and novel information: To our knowledge, this case describes the longest-lasting reported secondary hypoaldosteronism in a cat, after unilateral adrenalectomy for an adrenal carcinoma with hyperaldosteronism.

Presumed post-traumatic subdural hygroma in a 2.5-year-old spayed female Chihuahua.

A 2.5-year-old spayed female Chihuahua dog was presented with chronic cervical pain and exhibited a "prayer-like position" following a history of a 4-meter fall. CT and MRI revealed a moderate right-sided enlargement of the subdural space with cerebrospinal fluid, consistent with a subdural hygroma, appearing connected to a quadrigeminal cistern dilation. Percutaneous transfontanellar external drainage of the subdural fluid accumulation did not prevent its re-accumulation, and the dog was managed medically, leading to the complete resolution of clinical signs. The subdural hygroma was suspected to be secondary to the previous trauma.

C-reactive protein concentration has limited value in the diagnosis of meningoencephalitis of unknown origin in dogs.

OBJECTIVES: To evaluate blood and cerebrospinal fluid (CSF) concentrations of C-reactive protein (CRP) in dogs with meningoencephalitis of unknown origin (MUO); to evaluate whether blood CRP concentration is associated with epidemiological, clinicopathologic, and MRI findings; and to investigate blood CRP predictive power in survival. ANIMALS: 30 client-owned dogs with MUO, 15 client-owned dogs with steroid-responsive meningitis arteritis (SRMA; positive control group), and 15 healthy dogs (negative control group). METHODS: Blood CRP concentration was measured in each group, while it was performed in CSF only in the MUO and SRMA groups. The analysis of epidemiological data included breed, age, sex, duration of clinical signs, and history of seizures. Blinded analysis of MRI was performed based on a classification grid, and traditional CSF analysis parameters were assessed. The predictive power of blood CRP concentration regarding survival at 6 months was investigated. RESULTS: Of the 30 dogs with MUO, 9 (30%) had an increased CRP concentration in blood, and 3 (10%) showed a measurable CRP in CSF. Median blood CRP concentration in dogs with MUO was 0.1 mg/L (range, 0.1 to 102 mg/L), which was not statistically different from the healthy dog group but significantly lower than the SRMA control group. Only the duration of clinical signs was positively associated with an increased blood CRP level. Blood CRP concentration was not associated with survival at 6 months. CLINICAL RELEVANCE: Blood CRP concentration is of limited value for the diagnosis and prognosis of dogs with MUO. Chronicity of the disease may be associated with an increased concentration of blood CRP.

Effect of needle gauge on pain and specimen quality of ultrasound-guided fine needle sampling without aspiration of the canine spleen.

Modifications of splenic parenchyma are common ultrasonographic findings in dogs. Splenic fine needle aspiration (FNA) is a rapid, safe procedure, routinely performed in veterinary institutions. However, 22-gauge (G) needle usually reported is selected according to general practice and the most appropriate needle size to be used remains unclear. The aim of this prospective, single-center, methods comparison study was to assess the effect of needle size on cytologic specimens' evaluation and animal welfare during the procedure. Dogs underwent ultrasound-guided splenic FNA using 23, 25, and 27G needles. Needles were compared based on initial and then detailed cytologic evaluation. The initial evaluation assessed overall cellularity, cell preservation, hemodilution, and detailed cytologic evaluation referred to exhaustive splenic components. Welfare evaluation was performed based on a scoring system. A total of 54 dogs were included in this study with 54 of 54 welfare evaluations and 35 of 54 cytologic evaluations by one or two European College of Veterinary Clinical Pathology-certified cytologists. The final cytologic diagnosis was unchanged regardless of the needle size. For the initial evaluation, 23G needles provided significantly higher cellularity than the 27G needles. For detailed cytologic evaluation, only the richness in mesothelial cells and stroma was affected by needle size. Pain induced by the procedures was considered low using 23, 25, and 27G needles with the 27G needle producing the least adverse reactions. Findings from the current study supported using needle gauges smaller than the previously published standard 22G needle for spleen ultrasound-guided fine needle nonaspiration in dogs. Due to higher cellularity and lower pain scores, authors recommend the use of 23G needles with a nonaspiration technique.

Lumbosacral endplate contour defect is frequently observed concurrent with other lumbosacral abnormalities on spinal CT of French Bulldogs.

Lumbosacral osteochondrosis has been previously described in large breed dogs with variable clinical signs. Its CT features are a contour defect at the dorsal aspect of either vertebral endplate, commonly with an adjacent fragment. Descriptions of this condition have not been previously published in an increasingly popular breed, French Bulldogs. Aims of this retrospective, descriptive, single center study were to evaluate CT lumbosacral abnormalities and the frequency of lumbosacral endplate contour defect in a large sample of French Bulldogs. The presence and location of lumbosacral endplate contour defect and the presence of a concurrent osseous fragment were recorded. Other abnormal CT findings such as L7-S1 disc herniation, cauda equina nerve roots compression or thickening, disc mineralization, endplate sclerosis, spondylosis deformans, S1 articular processes hypertrophy, transitional vertebrae, hemivertebrae, spina bifida, and block vertebrae were recorded. Lumbosacral CT abnormalities were present in 91.8% of dogs (168/183). The most common abnormality was an L7-S1 dorsal disc herniation (77.4%, 130/168). Among dogs with lumbosacral abnormalities, the frequency of a lumbosacral endplate contour defect was 47% (79/168). It mostly involved L7 (78.5%, 62/79) at its dorsolateral aspect (61.3%, 38/62). A mineralized fragment was identified in 62% of the defects (49/79). Endplate contour defects were most frequently seen with a concurrent disc herniation (93.7%, 74/79) causing nerve root compression in 63.3% (50/79) and with sclerosis (65.8%, 52/79). There was no definitive evidence of a relationship with clinical presentation in this sample of French Bulldogs; therefore, this finding should be interpreted with caution. The etiology remains unclear.

Septic peritonitis secondary to intra-peritoneal grass awn migration: 7 cases (2014-2021).

Objectives: To describe the clinical presentation, management, and outcome of cases treated for septic peritonitis secondary to intra-peritoneal grass awn migration. Animals: Six client-owned dogs and 1 client-owned cat. Procedures: Clinical data of dogs and cats treated surgically for septic peritonitis secondary to an intra-peritoneal grass awn identified during surgery between January 2014 and December 2021 were retrospectively reviewed. Data included signalment, clinical presentation, blood test results, diagnostic imaging findings, surgical procedure, postoperative complications, and outcome. Telephone interviews were conducted for long-term follow-up. Results: Six dogs and 1 cat met the inclusion criteria. The most common reported clinical signs were lethargy (n = 7), anorexia/dysorexia (n = 4), and pyrexia (n = 4). The vegetal foreign body was not identified in any case with ultrasound (0/5) and only suspected for one case with a computed tomography scanner (1/4). A grass awn was identified within an omental abscess for each case during surgery. Abscess resection for each case resulted in partial pancreatectomy and a splenectomy for 1 case, and partial gastrectomy for another case. All cases survived to discharge. Only one minor post-operative complication was identified, and no other complication was reported at the long-term telephone interview. Conclusion and clinical significance: Septic peritonitis secondary to omental grass awn foreign body is an uncommon condition that has a good to excellent prognosis after surgical treatment. Identification of omental grass awn with ultrasound and computed tomography is rare. Therefore, particular care should be given to omental exploration during surgery for septic peritonitis with no underlying cause identified.

Péritonite septique secondaires à la migration de barbes de graminées : 7 cas (2014-2021). Objectifs: Décrire la présentation clinique, la prise en charge et pronostic des chiens et chats traité pour une péritonite septique secondaire à la migration intrapéritonéale d'un corps étranger végétal. Animaux: Six chiens et un chat traités. Protocole: Les informations des dossiers des chiens et chats pris en charge chirurgicalement pour une péritonite septique pour lesquelles un corps étranger végétal intrapéritonéal a été identifié entre janvier 2014 et décembre 2021 ont été obtenues. Les données concernant le signalement, la présentation clinique, les analyses sanguines, les examens d'imagerie, les procédures chirurgicales, les complications post-opératoires et l'évolution post-opératoire ont été collectées. Le suivi à long terme a été réalisé par téléphone. Résultats: Six chiens et un chat ont été inclus dans l'étude. Les signes cliniques les plus fréquents rapportés sont l'apathie (n = 7), l'anorexie/dysorexie (n = 4) et l'hyperthermie (n = 4). Les corps étrangers végétaux n'ont été identifiés dans aucun cas par échographie (0/5) et suspectés dans un cas à l'examen tomodensitométrique (1/4). Les corps étrangers ont tous été identifiés au sein d'un abcès dans l'omentum en chirurgie. Une résection de l'abcès a été réalisée dans chaque cas associé à une pancréatectomie partielle et une splénectomie pour un cas et une gastrectomie partielle pour un autre cas. Tous les animaux ont survécu. Seule une complication mineure a été rapportée en post-opératoire et aucune autre complication n'a été rapportée lors des entretiens téléphoniques. Conclusion et portée clinique: Les péritonites septiques secondaires à des migrations intra-péritonéale de corps étrangers végétaux sont des affections rares qui semblent être associées à un pronostic de survie bon à excellent après prise en charge chirurgicale. L'identification des corps étrangers dans l'omentum est difficile par échographie ou examen tomodensitométrique. Par conséquent, une attention particulière doit être portée à l'exploration de l'omentum lors de prise en charge chirurgicale de péritonite septique sans cause sous-jacente identifiée.(Traduit par les auteurs).

Comparison of computed tomography and surgical findings and investigation of their associations with outcomes for dogs with sublumbar abscesses.

OBJECTIVE: To describe and compare the results of preoperative CT and surgical findings in dogs with sublumbar abscesses and investigate potential associations between these variables and the outcome of abscess recurrence. ANIMALS: 51 client-owned dogs. PROCEDURES: A retrospective, records-based study was performed of dogs undergoing surgery for treatment of sublumbar abscesses diagnosed by use of CT between January 2010 and December 2018. Signalment, clinical signs, clinicopathologic data, CT findings, surgical techniques and findings, duration of hospitalization, postoperative treatment, and complications were recorded. Long-term follow-up was performed through telephone interviews. Logistic regression analysis was used to investigate associations between the variables of interest and abscess recurrence. RESULTS: 51 dogs met the study inclusion criteria; 48 were included in outcome analysis. The CT findings agreed with surgical findings for identification of a migrating vegetal foreign body for 39 of 51 (77%) dogs. All dogs survived to hospital discharge; 1 dog died of hemoabdomen 3 days after surgery, and 6 had minor (surgical wound) complications reported. Abscess recurrence developed in 12 of 48 (25%) dogs with a median time to recurrence of 6 months. Identification of diskospondylitis on CT examination was the only investigated factor significantly associated with recurrence; odds of recurrence in dogs with this finding were 8.4 times those for dogs without this finding. CONCLUSIONS AND CLINICAL RELEVANCE: Our results suggested dogs with sublumbar abscesses have a good prognosis after surgery, although recurrence can develop. Preoperative identification of diskospondylitis was significantly associated with abscess recurrence in this study sample.

Treatment and outcome of spontaneous pneumothorax secondary to suspected migrating vegetal foreign body in 37 dogs.

BACKGROUND: The aim of this study is to describe surgical findings, treatment and outcome of spontaneous pneumothorax (SP) secondary to suspected migrating vegetal foreign body (MVFB). METHODS: This retrospective study included dogs with computed tomography (CT) consistent with SP suspected to be secondary to MVFB that underwent thoracic surgery. They were divided into two groups according to whether CT identified (group 1) or only suspected (group 2) an MVFB. RESULTS: Thirty-seven dogs were included (twenty-one in group 1 and 16 in group 2). An MVFB was identified during surgery in 18 of 21 of cases of group 1 and in 10 of 16 of group 2. An agreement between lobes affected on CT and surgical findings was observed in 34 of 40 lobes. In nine of 37 of cases, a lung perforation was identified without evidence of MVFB. Thirty-nine lobectomies were performed: 15 complete and 24 partial. No recurrence of pneumothorax was observed. In four dogs, a second surgery was necessary to remove an MVFB 1.5 to 3 months after the initial surgery due to secondary draining tracts. CONCLUSION: Surgical approach planed with CT resolved SP in all cases before discharge with excellent short-term outcome and no major complication. CT was reliable to assess perforated lung lobes in 85% of cases. Clinical signs of delayed draining tract developed in 33% of cases where surgery failed to find an MVFB identified on CT.

Computed tomography may be helpful in discriminating grass awn foreign body rhinitis from non-foreign body rhinitis in dogs.

Grass awn foreign bodies are a common cause of rhinitis in dogs.  Early detection and complete removal of these foreign bodies are important for minimizing risks of long term complications. The objective of this retrospective, descriptive cross-sectional study was to determine whether discriminating CT findings exist between dogs with grass awn foreign body rhinitis and dogs with non-foreign body rhinitis. Computed tomography scans of 47 dogs with a confirmed diagnosis of non-foreign body rhinitis (25 cases) or of a nasal grass awn foreign body (22 cases) were reviewed. In the latter group, grass seeds were visualized directly on CT images for one of 22 (5%) cases. Focal lysis was more strongly associated with the presence of a grass awn foreign body (P = .012, LR = 3.0) and widespread lysis (involving more than one-third of the nasal cavity and/or bilateral) appeared associated with non-foreign body rhinitis (P = .046, LR = 2.0). Maxillary recess filling was associated with non-foreign body rhinitis (LR = 4.4) as was widespread lysis (LR = 2.0). Findings supported prioritizing grass awn foreign body rhinitis as a differential diagnosis for dogs with the former CT characteristics, even if a grass awn cannot be directly visualized.

CT is helpful for the detection and presurgical planning of lung perforation in dogs with spontaneous pneumothorax induced by grass awn migration: 22 cases.

Spontaneous pneumothorax induced by grass awns accounts for 5% of spontaneous pneumothorax and 22.5% of thoracic grass awn cases. Previous studies report limited interest of CT for spontaneous pneumothorax. Aims of this retrospective case series were to describe CT features of this condition and determine if CT features can efficiently localize the perforation site. Dogs that had a spontaneous pneumothorax, CT examination, thoracic surgery, and confirmed lung perforation due to a grass awn were included. Computed tomography studies were reviewed and compared to the surgical findings.  In 19 of 22 (86.4%) dogs, the pneumothorax or its recurrence were ipsilateral to the perforation site. The perforation site was identified in 21 of 22 (95.5%) dogs and involved the caudal lobes in 20 of 22 (90.9%) cases. The lateralization and the involved lung lobe corresponded to surgical findings in 21 of 22(95.5%) dogs. The perforation site was characterized as a soft tissue attenuating focus lying against an extensive pleural thickening in 21 of 22(95.5%) dogs. An adjacent defect in the visceral pleura was seen in 13 of 22(59.1%) dogs. A grass awn was seen in 11 of 22(50%) dogs.  The pneumothorax distribution and grass awn position consistently indicated the perforation side in this sample of dogs. The comparison with surgical findings suggests CT might be helpful for future presurgical planning of this etiology for pneumothorax.

Radiographic, computed tomographic, and arthroscopic diagnosis of radioulnar incongruence in dogs with medial coronoid disease.

OBJECTIVE: To characterize radioulnar incongruence (RUI) in large dogs with medial coronoid disease (MCD) and determine the agreement between radiography, computed tomography (CT), and arthroscopy. STUDY DESIGN: Prospective observational case series. ANIMALS: Twenty-four large-breed dogs under 3 years of age with confirmed MCD. METHODS: MCD and incongruence were evaluated by radiographs and CT. RUI was measured along the ulnar commissure, mid-body, and apex of the medial coronoid process (MCP) by CT and arthroscopy. Joints with RUI ≥ 2 mm were considered incongruent. Variables recorded during arthroscopic treatment included type of MCD, RUI, and modified Outerbridge score. Agreement between the 3 diagnostic imaging techniques was evaluated, and the association between RUI and cartilage damage was analyzed. RESULTS: Single fragmentation was the most common MCD according to CT and arthroscopy. RUI was associated with degenerative joint disease according to CT and with cartilage damage according to arthroscopy. RUI was diagnosed in 26% of elbows by radiography, in 35% of elbows by CT, in 78% of elbows according to CT measurements of RUI ≥ 2 mm, and in 57% of joints by arthroscopy. RUI was most commonly detected at the ulnar commissure with CT and at the apex of the MCP with arthroscopy. Imaging modalities were in poor to fair agreement with arthroscopy when evaluating RUI. CONCLUSION: CT and arthroscopy provided similar detection of MCD and cartilage disease but disagreed in the assessment and localization of RUI. CLINICAL SIGNIFICANCE: CT does not reliably predict arthroscopic assessment of RUI and associated treatment decisions for MCD.

Use of a novel surgical approach for treatment of complete bilateral membranous choanal atresia in an alpaca cria.

CASE DESCRIPTION A 4-hour-old 6.3-kg (13.9-lb) female alpaca cria was evaluated because of severe respiratory distress and difficulty nursing since birth. CLINICAL FINDINGS The cria had open-mouth breathing and cyanotic membranes, with no airflow evident from either nostril. Supplemental oxygen was delivered, and the patient was anesthetized and intubated orotracheally; a CT evaluation of the head confirmed bilateral membranous obstruction of the nasal cavities, consistent with complete bilateral choanal atresia. TREATMENT AND OUTCOME Choanal atresia was treated with an endoscopically assisted balloon-dilation technique, and temporary tracheostomy was performed. Stenosis recurred, requiring revision of the repair and intranasal stent placement 3 days after the first surgery. The tracheostomy tube was removed the next day. Complications during hospitalization included mucoid obstruction of the tracheostomy tube, granulation tissue development in the trachea near the tracheostomy site, mucoid stent obstruction, aspiration pneumonia, and presumed partial failure of passive transfer of immunity. The stents were removed 2 weeks after admission, and the cria was discharged 3 days later. The owner was advised that the animal should not be bred. At last follow-up 3 years later, the alpaca was doing well. CLINICAL RELEVANCE Surgical treatment with a balloon-dilation technique and placement of nasal stents with endoscopic guidance were curative in this neonatal alpaca with bilateral membranous choanal atresia. Computed tomography was useful to determine the nature of the atresia and aid surgical planning. Because a genetic component is likely, owners should be advised to prevent affected animals from breeding.

COMPARISON OF THORACIC ULTRASONOGRAPHY AND RADIOGRAPHY FOR THE DETECTION OF INDUCED SMALL VOLUME PNEUMOTHORAX IN THE HORSE.

Small volume pneumothorax can be challenging to diagnose in horses. The current standard method for diagnosis is standing thoracic radiography. We hypothesized that thoracic ultrasonography would be more sensitive. Objectives of this prospective, experimental study were to describe a thoracic ultrasound method for detection of small volume pneumothorax in horses and to compare results of radiography and ultrasound in a sample of horses with induced small volume pneumothorax. Six mature healthy horses were recruited for this study. For each horse, five 50 ml air boluses were sequentially introduced via a teat cannula into the pleural space. Lateral thoracic radiographs and standardized ultrasound (2D and M-mode) examinations of both hemithoraces were performed following administration of each 50 ml air bolus. Radiographs and ultrasound images/videos were analyzed for detection of pneumothorax by four independent investigators who were unaware of treatment status. Sensitivity, specificity, positive predictive values, negative predictive values, and agreement among investigators (Kappa test, κ) were calculated for radiography, 2D and M-mode ultrasound. Comparisons were made using a chi-squared exact test with significance set at P < 0.05. Two-dimensional (84%) and M-mode (80%) ultrasound were more sensitive than radiography (48%) for pneumothorax detection (P = 0.02 and P = 0.04, respectively). Specificity and positive predictive values were similar for all three imaging modalities (P = 1). Agreement between investigators for pneumothorax detection was excellent for 2D ultrasound (κ = 1), very good for M-mode ultrasound (κ = 0.87), and good for radiography (κ = 0.79). Findings from this experimental study supported the use of thoracic ultrasonography as a diagnostic method for detecting pneumothorax in horses.

A pitfall on postoperative radiographs in dogs after tibial plateau leveling osteotomy.

OBJECTIVE: To identify the cause of an occasional radiolucent line in the tibia on postoperative radiographs after tibial plateau leveling osteotomy (TPLO) in dogs. STUDY DESIGN: Retrospective case series and ex vivo experiment. SAMPLE POPULATION: Dogs (n = 80; 87 stifles) with cranial cruciate ligament (CCL) rupture that had TPLO; and 4 canine tibia specimens. METHODS: Medical records (2007-2010) and radiographs of dogs that had TPLO were reviewed and examined for presence of a radiolucent line on postoperative radiographs. The TPLO procedure was reproduced ex vivo to determine the origin of this line by use of metallic wires to identify bone contours. RESULTS: A curvilinear radiolucent line was visible in 14 (16%) tibias and was 5.4 times more likely to be visible with lateral misalignment of the tibial diaphysis relative to the plateau and 2.6 times more likely visible on caudocranial radiographs with the stifle in outward rotation. Fracture complication rate was higher in dogs with this radiolucent line (P = .02) and with lateral misalignment of the tibial diaphysis relative to the plateau (risk ratio, 3.8). The line could be reproduced ex vivo and caused by superimposition of the craniomedial border of osteotomy with the tibial plateau. CONCLUSIONS: The radiolucent line was a spurious fracture line created by the medial margin of the tibial osteotomy and confounding factors such as tibial misalignment may explain the apparently associated higher complication rate.

A posteriori comparison of natural and surgical destabilization models of canine osteoarthritis.

For many years Canis familiaris, the domestic dog, has drawn particular interest as a model of osteoarthritis (OA). Here, we optimized the dog model of experimental OA induced by cranial cruciate ligament sectioning. The usefulness of noninvasive complementary outcome measures, such as gait analysis for the limb function and magnetic resonance imaging for structural changes, was demonstrated in this model. Relationships were established between the functional impairment and the severity of structural changes including the measurement of cartilage thinning. In the dog model of naturally occurring OA, excellent test-retest reliability was denoted for the measurement of the limb function. A criterion to identify clinically meaningful responders to therapy was determined for privately owned dogs undergoing clinical trials. In addition, the recording of accelerometer-based duration of locomotor activity showed strong and complementary agreement with the biomechanical limb function. The translation potential of these models to the human OA condition is underlined. A preclinical testing protocol which combines the dog model of experimental OA induced by cranial cruciate ligament transection and the Dog model of naturally occurring OA offers the opportunity to further investigate the structural and functional benefits of disease-modifying strategies. Ultimately, a better prediction of outcomes for human clinical trials would be brought.

Foetal and postnatal equine articular cartilage development: magnetic resonance imaging and polarised light microscopy.

Adult articular cartilage (AC) has a well described multizonal collagen structure. Knowledge of foetal AC organisation and development may provide a prototype for cartilage repair strategies, and improve understanding of structural changes in developmental diseases such as osteochondrosis (OC). The objective of this study was to describe normal development of the spatial architecture of the collagen network of equine AC using 1.5 T magnetic resonance imaging (MRI) and polarised light microscopy (PLM), at sites employed for cartilage repair studies or susceptible to OC. T2-weighted fast-spin echo (FSE) sequences and PLM assessment were performed on distal femoral epiphyses of equine foetuses, foals and adults. Both MRI and PLM revealed an early progressive collagen network zonal organisation of the femoral epiphyses, beginning at 4 months of gestation. PLM revealed that the collagen network of equine foetal AC prior to birth was already organised into an evident anisotropic layered structure that included the appearance of a dense tangential zone in the superficial AC in the youngest specimens, with the progressive development of an underlying transitional zone. A third, increasingly birefringent, radial layer developed in the AC from 6 months of gestation. Four laminae were observed on the MR images in the last third of gestation. These included not only the AC but also the superficial growth plate of the epiphysis. These findings provide novel data on normal equine foetal cartilage collagen development, and may serve as a template for cartilage repair studies in this species or a model for developmental studies of OC.

Interobserver agreement and diagnostic accuracy of brain magnetic resonance imaging in dogs.

OBJECTIVE: To evaluate interobserver agreement and diagnostic accuracy of brain MRI in dogs. DESIGN: Evaluation study. ANIMALS: 44 dogs. PROCEDURES: 5 board-certified veterinary radiologists with variable MRI experience interpreted transverse T2-weighted (T2w), T2w fluid-attenuated inversion recovery (FLAIR), and T1-weighted-FLAIR; transverse, sagittal, and dorsal T2w; and T1-weighted-FLAIR postcontrast brain sequences (1.5 T). Several imaging parameters were scored, including the following: lesion (present or absent), lesion characteristics (axial localization, mass effect, edema, hemorrhage, and cavitation), contrast enhancement characteristics, and most likely diagnosis (normal, neoplastic, inflammatory, vascular, metabolic or toxic, or other). Magnetic resonance imaging diagnoses were determined initially without patient information and then repeated, providing history and signalment. For all cases and readers, MRI diagnoses were compared with final diagnoses established with results from histologic examination (when available) or with other pertinent clinical data (CSF analysis, clinical response to treatment, or MRI follow-up). Magnetic resonance scores were compared between examiners with κ statistics. RESULTS: Reading agreement was substantial to almost perfect (0.64 < κ < 0.86) when identifying a brain lesion on MRI; fair to moderate (0.14 < κ < 0.60) when interpreting hemorrhage, edema, and pattern of contrast enhancement; fair to substantial (0.22 < κ < 0.74) for dural tail sign and categorization of margins of enhancement; and moderate to substantial (0.40 < κ < 0.78) for axial localization, presence of mass effect, cavitation, intensity, and distribution of enhancement. Interobserver agreement was moderate to substantial for categories of diagnosis (0.56 < κ < 0.69), and agreement with the final diagnosis was substantial regardless of whether patient information was (0.65 < κ < 0.76) or was not (0.65 < κ < 0.68) provided. CONCLUSIONS AND CLINICAL RELEVANCE: The present study found that whereas some MRI features such as edema and hemorrhage were interpreted less consistently, radiologists were reasonably constant and accurate when providing diagnoses.

Computed tomography and magnetic resonance imaging in the study of joint development in the equine pelvic limb.

Osteochondrosis dissecans (OCD) is a focal failure of endochondral ossification of the epiphysis characterized by the presence of cartilage flaps and osteochondral fragments. The objective of this study was to image epiphyseal development in the equine pelvic limb to determine whether there was a variation in site maturation that could be a predisposing factor for OCD. Pelvic limbs (fetuses and foals) were studied post-mortem. The epiphyses of the distal femur, tibia and talus were scanned with computed tomography (CT) and 1.5T magnetic resonance imaging (MRI) to investigate the degree and pattern of ossification, the regularity of the ossification front and cartilage percentage (articular epiphyseal cartilage thickness as a percentage of total epiphyseal diameter) at predetermined sites. The secondary ossification centers (SOCs) were first identified in the femoral epiphyses at 7months, and both tibia and talus at 8months of gestation (MOG). At ⩾8 MOG the cartilage percentage was higher at the majority of OCD-susceptible sites when compared to control sites. At 8-9 MOG the lateral trochlear ridge of the femur, medial malleolus of the tibia (MM), cranial part of the distal intermediate ridge of the tibia (DIRT(Cr)), all OCD susceptible sites, had the greatest cartilage percentage compared to all other sites assessed. Post-partum, the cartilage percentage of the MM and DIRT(Cr), common sites of OCD, remained high. CT and MRI images illustrate equine epiphyseal development and provide additional evidence that greater cartilage thickness at specific joint sites could play a role in the development of OCD.

Imaging of primary bone tumors in veterinary medicine: which differences?

Veterinary medicine is most often a mysterious world for the human doctors. However, animals are important for human medicine thanks to the numerous biological similarities. Primary bone tumors are not uncommon in veterinary medicine and especially in small domestic animals as dogs and cats. As in human medicine, osteosarcoma is the most common one and especially in the long bones extremities. In the malignant bone tumor family, chondrosarcoma, fibrosarcoma and hemangiosarcoma are following. Benign bone tumors as osteoma, osteochondroma and bone cysts do exist but are rare and of little clinical significance. Diagnostic modalities used depend widely on the owner willing to treat his animal. Radiographs and bone biopsy are the standard to make a diagnosis but CT, nuclear medicine and MRI are more an more used. As amputation is treatment number one in appendicular bone tumor in veterinary medicine, this explains on the one hand why more recent imaging modalities are not always necessary and on the other hand, that prognostic on large animals is so poor that it is not much studied. Chemotherapy is sometimes associated with the surgery procedure, depending on the aggressivity of the tumor. Although, the strakes differs a lot between veterinary and human medicine, biological behavior are almost the same and should led to a beneficial team work between all.

Cervical discospondylitis in 2 Great Dane puppies following routine surgery.

Two Great Dane puppies developed cervical discospondylitis following routine surgery for sterilization. One animal was affected at C4-C5 and the other at C6-C7 intervertebral discs. Pseudomonas aeruginosa was obtained in pure culture from ultrasound-guided disc aspiration in 1 case. Both animals were successfully treated with long-term antibiotics.