Management of paracondylar process fracture in three horses.

BACKGROUND: Fractures of the paracondylar process of the occipital bone may cause headshaking, neck pain and neurologic deficits. The condition is being recognised more frequently with increasing availability of computed tomography. However, to date only limited information is available as to presentation, treatment, surgical approach and outcome. OBJECTIVES: To describe the clinical signs, imaging findings, treatment, surgical approach and outcome in three horses diagnosed with paracondylar process fracture. STUDY DESIGN: Retrospective case series. METHODS: Clinical records and diagnostic images of affected cases were reviewed. RESULTS: Two cases had ventral nonunion fractures-one of these presented with neck pain, headshaking and behavioural changes, while in the other the fracture was a suspected incidental finding in a case of poor performance. A third case with a more dorsal fracture presented with acute facial nerve paralysis. Diagnosis was by computed tomography in all cases, although imaging of ventral fractures by radiography was found to be feasible. Where clinical signs could be associated confidently with the fracture, conservative management resulted in improvement but not complete resolution. Repeated recurrence of clinical signs after prolonged periods of remission necessitated surgical removal in one case, which was readily accomplished with the aid of ultrasound guidance, and led to rapid resolution of clinical signs without significant post-operative complications. The surgical approach is described. MAIN LIMITATIONS: Limited follow-up was available. CONCLUSIONS: Paracondylar process fracture should be considered as a differential diagnosis for headshaking, neck pain, poor performance and facial paresis, and is a justification for performing computed tomography in such cases. A multi-disciplinary approach is beneficial due to the potential for orthopaedic, neurologic, ophthalmologic and behavioural clinical signs, with additional need for expertise in diagnostic imaging and pain management. Surgical fragment removal should be considered for ventral fractures.

Ocular biometry in rabbits using computed tomography.

OBJECTIVE: To describe a repeatable method of measuring ocular structures and to establish ocular biometry reference ranges in adult domestic rabbits (Oryctolagus cuniculus) without medical history or imaging findings consistent with ophthalmic disease using a 64-slice multidetector computed tomography scanner. PROCEDURE: In this retrospective and observational anatomic study, 100 eyes from 50 rabbits without medical history or imaging findings consistent with ophthalmic disease who received a head computed tomography scan were selected for measurement of globe length, width, and height using 3D multiplanar reconstruction. Lens width and length, the anteroposterior length of the anterior and vitreous chambers, and attenuation of the lens and vitreous chamber were collected. These parameters were compared against age, sex, weight, body condition, and ear conformation. RESULTS: A reference guide was established, with globe width being the largest dimension (18.03 ± 0.81 mm), followed by height (17.18 ± 0.69 mm) and then length (16.64 ± 0.66 mm). Increased weight was associated with an increase in globe height (p = 2.43 × 10-5 ), length (p = 1.63 × 10-4 ), and width (p = 7.0 × 10-3 ). Increased age was associated with increased lens attenuation (p = 1.28 × 10-7 ) and increased transverse lens width (p = 1.64 × 10-3 ). Inter- and intra-observer agreement was excellent. CONCLUSIONS: CT is a reliable modality for measurement of ocular biometry dimensions in rabbits. These reference values can be applied to aid in identifying diseases that affect the dimensions of the ocular structures in rabbits over 18 months of age.

Resolution of megaesophagus after correction of a paraesophageal hernia.

Case summary: A 6-year-old female Siamese cat presented with an 8-week history of vomiting and progressive hyporexia. On presentation, the cat was found to have a hypochloremic alkalosis. Imaging demonstrated hiatal hernia and megaesophagus. Exploratory laparotomy demonstrated a paraesophageal hiatal hernia. The hernia was reduced, phrenoplasty and esophagopexy were performed, and a gastrotomy tube was placed. Treatment of the hernia led to resolution of the megaesophagus. Relevance and novel information: Megaesophagus can occur secondarily to paraesophageal hernia in the cat. In this case, correction of the paraesophageal hernia led to complete resolution of the esophageal dilation and all associated clinical signs.

Fall time may be a reliable discriminator between neoplastic and non-neoplastic urinary bladder lesions in dogs undergoing contrast-enhanced ultrasound: a pilot study.

Contrast-enhanced ultrasound (CEUS) can provide quantitative information on enhancement patterns and perfusion of lesions, based on time-intensity curves (TICs). No published studies have compared CEUS parameters in neoplastic and non-neoplastic urinary bladder lesions in dogs. The aim of the current prospective, pilot study was to quantitatively characterize the CEUS pattern of neoplastic and non-neoplastic urinary bladder lesions in dogs, assessing the influence of contrast arrival time (CAT) on the final appearance of the curves. Fourteen dogs with cyto-histopathological diagnoses were included (seven malignant and seven inflammatory lesions). B-mode ultrasound was performed followed by CEUS examination after an intravenous bolus injection of 0.04 mL/kg of contrast medium, and TICs were elaborated by dedicated software. Receiver operating characteristic curves (ROC) for each TIC parameter were obtained. Neoplastic lesions had subjectively shorter rise time (RT), time to peak (TTP) and fall time (FT) than inflammatory lesions. Based on ROC curve analyses, fall time ≥ 10.49 s was the most reliable parameter for diagnosing non-neoplastic disease in this small sample of dogs (area under the curve [AUC] 0.75, sensitivity 83.33%, specificity 66.67%). No difference was found between ROCs calculated for each parameter of TICs by adding or removing CAT. Results of the current study provide background for future, larger scale studies evaluating use of a CEUS FT threshold of 10.49 s as a possible discriminator for urinary bladder neoplastic lesions in dogs.

Clinical and CT sialography findings in 22 dogs with surgically confirmed sialoceles.

Sialoceles are an uncommon canine salivary gland disease, and complete surgical resection is important for a positive outcome. Radiographic sialography has been described as a diagnostic test for presurgical planning; however, superimposition artifacts may limit the diagnosis and detection of all affected glands. Computed tomographic (CT) sialography is a promising technique for delineating the salivary gland apparatus. The aims of this retrospective, observational study were to describe clinical and CT sialographic findings in a group of dogs with confirmed sialoceles, to determine the sensitivity of CT sialography for detecting affected salivary glands using surgery as the reference standard and to determine interobserver agreement for CT sialographic assessments. Dogs were included if they underwent a CT sialography study followed by surgical resection of the diseased gland(s) and histopathological analysis. Computed tomography sialography studies of dogs with surgically confirmed sialoceles (n = 22) were reviewed by a European College of Veterinary Diagnostic Imaging (ECVDI)-certified radiologist and an ECVDI resident. Interobserver agreement was calculated using Cohen's kappa statistics. CT sialography results were compared to surgical findings to determine sensitivity. Contrast leakage was detected in 12 of 22 dogs (54.5%), with intrasialocele leakage being most frequently observed (7/12, 58.3%). There was substantial agreement (κ = 0.70) between reviewers identifying diseased glands, substantial agreement (κ = 0.62) on the diagnostic quality, and no to slight agreement (к = 0.13) in the detection of contrast leakage. The overall sensitivity of CT sialography to detect surgically confirmed diseased glands was 66.7% (95% confidence interval: 48.8-80.8). In conclusion, these findings support the use of CT sialography as an adjunct diagnostic test for treatment planning in dogs with sialoceles.

Safety of intravenous iodinated contrast medium injection in rabbits undergoing conscious computed tomography.

Background: Contrast media in CT is widely used in dogs and cats to provide superior tissue delineation and increase the diagnostic capabilities. These contrast-enhanced imaging techniques are gaining popularity in rabbits; published studies reporting the safety of doing so are lacking. Methods: This retrospective observational study aimed to determine the incidence of adverse events following the intravenous administration of iodinated non-ionic contrast medium in 350 rabbits. The medical records of this subset of rabbits admitted between January 2009 and November 2018, that underwent CT examination and received intravenous contrast media, were evaluated. Results: From the 350 rabbits, 342 rabbits were still alive 7 days after the scan. A total of eight rabbits died within 7 days of the scan, seven of which within the first 24 h. All deaths were presumed to be sequelae to the diseases they were being investigated for and not thought to be related to the administration of intravenous contrast medium. Conclusions: The results indicated that the use of intravenous non-iodinated contrast medium was well tolerated and safe in rabbits undergoing conscious CT examination.

Utility of a flexed neck sagittal magentic resonance imaging sequence for the assessment of cerebellomedullary cistern in dogs.

Cerebrospinal fluid (CSF) collection from the cerebellomedullary cistern (CM) of dogs with congenital or acquired cerebellar herniation could lead to serious complications. It is anecdotally more challenging in large brachycephalic breeds possibly due to the increased distance between the skin and CM. The first objective of this study was to assess whether flexed-neck sagittal magnetic resonance imaging (MRI) sequences would assist in the decision-making process of collecting CSF from the CM. The second objective was to examine the dimensions of the CM measured in extended and flexed views, and whether cranial index (CI), skull height and body weight correlated with the distance of the CM from the skin surface. Forty-one dogs of various breeds were included in the study. Measurements were performed on T2-weighted sagittal sequences acquired in extended and flexed-neck positions, and transverse sequences acquired in an extended-neck position. Mild cerebellar herniation was detected in 23/41 (56%) of the flexed-neck views versus none in the extended views. The CM area was significantly larger in flexed-neck views than in extended views (p < 0.05). In 29% of the cases (12/41), the trajectory of the needle intersected the cerebellar vermis. There was a positive correlation between the distance of the CM from the skin and body weight (p < 0.05) and skull height (p < 0.05), but not with the CI (p = 0.23). These findings suggest that a flexed-neck sagittal MRI sequence helps with assessment of the size of the CM and degree of cerebellar herniation, and that skull height and body weight, but not cranial index, affect the distance of the CM from the skin surface.

Anatomical localisation of the maxillary nerve with the use of computed tomography to aid nerve block placement in dogs.

BACKGROUND: The maxillary block is a commonly used anaesthetic technique in dogs; however, no universal recommendations for the best method to perform this block exist. Differences between using this block in brachycephalic and non-brachycephalic breeds have not been examined. This study compared the position of the maxillary nerve using CT in brachycephalic and non-brachycephalic dogs. METHODS: Forty CT images of the heads of dogs of varying conformation were analysed. The distances and angles to the maxillary nerve from the injection site within the oral cavity were measured. If present in the same plane, the distance to the eye was measured. Measurements of jaw width and length were taken to ascertain if they correlated to the distance to the maxillary nerve from the oral cavity. RESULTS: There was no difference in angle between brachycephalic and non-brachycephalic dogs; however, the distance between nerve and injection point in brachycephalic dogs was generally greater. A regression equation relating maxillary nerve depth to jaw width was found. The eye was more likely to be in the plane of injection if the dog was non-brachycephalic. CONCLUSION: The discovered relationship between jaw width and maxillary nerve depth may allow more accurate injections to be made.

Arterial malformations leading to bilateral spontaneous renal hemorrhage in a dog.

OBJECTIVE: To describe the clinical presentation, diagnostic imaging, management, and follow-up of a dog that presented with sequential, bilateral, spontaneous, subcapsular and perirenal hemorrhage (Wunderlich syndrome) due to bilateral renal arterial malformations. CASE SUMMARY: A 9-year-old intact male Field Spaniel presented for acute onset abdominal pain following a possible syncopal episode. Abdominal ultrasonography, contrast-enhanced ultrasound, and computed tomography (CT) revealed right-sided perirenal hemorrhage that extended into the peritoneum. The dog was discharged following stabilization with analgesia, fluid therapy, and tranexamic acid. One month later, the patient presented with identical clinical signs. A CT scan at this stage revealed bilateral kidney infarcts with new left-sided perirenal hemorrhage. Abdominal ultrasound and contrast-enhanced ultrasound were repeated and showed similar findings. Follow up with four-dimensional CT angiography revealed bilateral renal arterial malformations, likely causing spontaneous renal hemorrhage and secondary subcapsular hematomas , retroperitoneal and peritoneal hemorrhage. UNIQUE INFORMATION PROVIDED: This is the first reported case of both bilateral renal arterial malformations and bilateral spontaneous subcapsular and perirenal hemorrhage in the absence of neoplasia, coagulopathy, or trauma in a dog. Advanced imaging modalities, including selective angiography, were required to diagnose this condition successfully. Arterial malformations should be considered as a differential diagnosis in cases of hemoretroperitoneum. Nephrectomy due to perirenal hemorrhage should be cautiously considered, especially in the absence of angiography, because of the sequential bilateral nature of this case. Conservative management in this case resulted in a good long-term outcome 10 months later.

What Is Your Diagnosis?

In collaboration with the American College of Veterinary Radiology.

Congenital Urethrovaginal Fistula with Blind-Ending Vagina in a Female Pseudohermaphrodite Dog with Urinary Incontinence.

An 8 mo old male Doberman pinscher was referred for investigation of persistent urinary incontinence. Physical examination revealed urine leakage and abnormal external genitalia. A computed tomography scan identified a large fluid-filled cavity extending from the caudoventral abdomen displacing the colon and urinary bladder. No retained testicles were identified. A retrograde urethrogram study found a linear communication, cranial to the pubic brim between the urethra to the fluid-filled cavity (fistula). Exploratory celiotomy was performed, and an entire female reproductive tract with a blind-ending vagina and a urethrovaginal fistula was found. En bloc gonad hysterectomy was performed, the fistula was transected, and a careful urethral reconstruction was performed. The urinary incontinence resolved immediately after surgery, and no complications were reported. Mild urinary incontinence recurred 4 days following patient discharge, and a urine bacterial culture was positive for Klebsiella spp. An antibiotic course was prescribed, and the incontinence fully resolved. Congenital urogenital abnormalities should always be considered in young animals presenting with urinary incontinence. Here, a young female pseudohermaphrodite dog with a naturally occurring congenital urethrovaginal fistula is described. Exploratory surgery was required for definitive diagnosis and surgical intervention yielded a good medium-term outcome with resolution of clinical signs.

Imaging findings in 14 dogs and 3 cats with lobar emphysema.

BACKGROUND: Lobar emphysema in dogs and cats is caused by bronchial collapse during expiration and subsequent air trapping. Congenital causes such as bronchial cartilage defects or acquired causes such as compressive neoplastic lesions have been reported. Morbidity results from hyperinflation of the affected lung lobe and compression of adjacent thoracic structures. OBJECTIVE: To describe patient characteristics and imaging findings in dogs and cats with lobar emphysema. ANIMALS: Fourteen dogs and 3 cats with lobar emphysema diagnosed by imaging findings were retrospectively identified from veterinary referral hospital populations over a 10-year period. METHODS: Cases that included thoracic radiography, thoracic computed tomography (CT), or both were included. All images were reviewed by a European College of Veterinary Diagnostic Imaging diplomate. Relevant case information included signalment, clinical findings, treatment, and histopathology where available. RESULTS: Ten of 17 (59%) patients were presented for evaluation of dyspnea and 6 (35%) for coughing. Eleven (65%) patients were <3 years of age. The right middle lung lobe was affected in 12 cases (71%) and multiple lobes were affected in 7 cases (41%). Congenital lobar emphysema was suspected in 14 cases (82%). CONCLUSION AND CLINICAL IMPORTANCE: Lung lobe hyperinflation, atelectasis of nonaffected lung lobes, mediastinal shift, and thoracic wall and diaphragmatic wall deformation were common findings. Lobar or multilobar emphysema should be considered in patients with dyspnea or coughing, particularly younger patients. Although radiography is useful, CT provides better detail. In older patients, acquired causes of bronchial compression should be considered.

Computed Tomography Osteodensitometry for Assessment of Bone Mineral Density of the Canine Head-Preliminary Results.

Despite bone mineral density (BMD) being regularly measured in human patients, BMD studies in clinical cohorts of dogs is lacking. In order to facilitate BMD assessment and in turn better identify dogs suffering from metabolic bone disease, rapid, easy and precise computed tomography (qCT) techniques are required. In this study we aimed to assess the utility of quantitative computed tomography (qCT) bone mineral density (BMD) measurement of the canine calvarium using a semiautomated osteodensitometry software and define host factors associated with canine bone mineral density in a skeletally healthy population. Calvarial qCT at the level of the temporomandibular joints was performed on 323 dogs using a dedicated osteodensitometry calibration phantom during a clinically indicated head computed tomography (CT). Calvarial BMD was analyzed using a dedicated semiautomatic osteodensitometry software for contouring of the calvarial lamellar bone margins and BMD calculation. The mean duration of the calvarial qCT scanning was 64.6 s, and the mean duration of BMD analysis was 34 s, with a mean of two manual adjustments required for the bone margin tracing. The median BMD of all dogs in our study was 659 mg Calcium hydroxyapatite/mL. There was a negative linear correlation between BMD and body weight, but no correlation with age, sex or neutered status. Canine BMD assessment using qCT of the calvarium is a practical and fast technique that can be added to a clinical CT examination with minimal extra time requirements. Canine BMD host-dependent factors exhibit different relationships from that of humans; however, further investigation is warranted.

Multidetector CT and cone-beam CT have substantial agreement in detecting dental and sinus abnormalities in equine cadaver heads.

The performance of cone-beam CT (CBCT) systems compared to conventional helical multidetector CT (MDCT) imaging of the equine head is unknown. The aim of this prospective, method-comparison study was to compare the ability of CBCT and MDCT to detect abnormalities in equine cadaver heads. Eleven equine cadaver heads were scanned using a CBCT scanner and a 64-slice MDCT scanner. Consensus evaluations for CBCT and MDCT scans were performed by three observers. Identified abnormalities were grouped into subcategories with a focus on dental abnormalities. Kappa agreement values between detected abnormalities for CBCT and MDCT methods were calculated. Of 468 teeth evaluated, 122 (26.1%) were found to have abnormalities (including in 58 infundibula and 7 pulps) using MDCT and 105 (22.4%) were found to have abnormalities (including in 52 infundibula and 2 pulps) using CBCT. The agreement between CBCT and MDCT was almost perfect for overall detection of dental abnormalities (k = 0.90) with k = 1 for diastema k = 0.95 for clinical crown abnormalities, and k = 0.93 for infundibular abnormalities. However, the detection of pulp changes by CBCT was only moderate k = 0.44. Increased scatter radiation, non-calibrated Hounsfield Unit and artefacts in CBCT images made accurate identification of the pulp density difficult. In conclusion, CBCT results were similar to conventional MDCT for the majority of dental abnormalities, however, pulp abnormalities were not reliably identified using CBCT, potentially limiting its clinical use for detecting endodontic disease in its current form. Further comparison with more cases with confirmed dental disease and studies in clinical cases are warranted.

Studies on Age-Related Changes in Equine Cheek Teeth Angulation and Dental Drift.

BACKGROUND: Cheek teeth (second through fourth premolars and first through third molars) diastema is a common and painful equine disorder caused by the absence of effective tight interdental contact between these teeth. Limited objective information is available on the angulation of equine cheek teeth that control dental drift or on mesial or distal equine cheek teeth drift that should normally prevent this disorder. OBJECTIVES: To measure the angulation of the mesial and distal cheek teeth in horses of different ages, quantify age-related cheek teeth mesial and distal dental drift, and measure the cheek teeth row length in horses of different ages. STUDY DESIGN: Retrospective review of computed tomographic images of equine heads. METHODS: Case details and CT images from clinical equine cases that had undergone standing CT head examination were collated.Three sets of measurements were acquired from each head. "Head size" calculated as the distance between the caudal aspect of the orbit and the caudal aspect of the naso-incisive notch was used to standardize measurements in different sized heads. The length of the cheek teeth rows measured from the mesial aspect of the Triadan 06 occlusal surface to the distal aspect of the Triadan 11 occlusal surface. The rostro-caudal (antero-posterior) position and angulation of the mandibular and maxillary Triadan 06 and 11 teeth were measured in relation to reference lines drawn on CT images. RESULTS: Significant mesial drift occurred in the maxillary and mandibular Triadan 11s. Despite their distal angulation, the upper and lower Triadan 06s also drifted mesially. The mean angulation of Triadan 06 and 11 mandibular teeth (17.8 and 26.2°, respectively) was almost double that of maxillary teeth (9.2 and 13.3°, respectively) with both Triadan 11s having greater angulation than the 06s. Cheek teeth angulation only significantly decreased in the mandibular 06s. Cheek teeth arcade lengths decreased with age, but these decreases were not significant. MAIN LIMITATIONS: Limitations include the relatively small sample size. CONCLUSIONS: In the population of horses used for this study, age related mesial drift occurred in both Triadan 06 and 11s, and the angulation of these teeth did not decrease with age in most arcades.

Contrast-enhanced ultrasound for sentinel lymph node mapping in the routine staging of canine mast cell tumours: A feasibility study.

Canine mast cell tumours (MCTs) typically spread to lymph nodes (LNs) before reaching distant sites, and LN assessment is an important part of MCT staging. Sentinel LN (SLN) mapping techniques to identify draining LNs are being developed and could improve the accuracy of MCT staging. The primary objective of this feasibility study was to determine the safety and effectiveness of contrast-enhanced ultrasound (CEUS) to identify SLNs. Secondary objectives were to determine if the SLNs identified by CEUS coincided with the regional LN predicted by the anatomical lymphosomes, if previous MCT excision altered CEUS SLN findings, and if CEUS could identify MCT nodal metastases. Between June 2017 and March 2019, 59 dogs with 62 MCTs were enrolled. No adverse events related to CEUS were reported. CEUS detected at least 1 SLN in 59/62 MCTs (95.2%, 95% CI: 86.5-99.0%). In only 32/59 (54.2%) MCTs, clinicians would have correctly predicted the SLN(s) identified by CEUS. Among the 35 MCTs that had histological examination of the SLN(s), the prevalence of metastasis was 60% (95% CI: 42.1-76.1%). Additional staging procedures did not reveal any metastases in dogs with histologically non-metastatic SLNs. Integration of CEUS SLN mapping into the routine staging of MCTs is promising, but future studies are required to refine this procedure and to investigate if it would translate into a clinical benefit.

Correlation of minimally invasive imaging techniques to assess intestinal mucosal perfusion with established markers of chronic inflammatory enteropathy in dogs.

BACKGROUND: Minimally invasive diagnostic imaging techniques to detect intestinal inflammation in dogs are lacking. Contrast-enhanced ultrasound (CEUS) and endoscopic narrow band imaging-like endoscopy (Storz Professional Image Enhancement System [SPIES]) might allow quantification of intestinal mucosal perfusion and microvessel density in chronic inflammatory enteropathy (CIE) of dogs. HYPOTHESIS/OBJECTIVES: Markers of mucosal perfusion as determined by CEUS and SPIES endoscopy are potentially useful diagnostic markers to help characterize CIE and correlate with histological inflammation type and severity. ANIMALS: Thirty client-owned dogs diagnosed with CIE at a referral hospital were prospectively enrolled. MATERIALS AND METHODS: Data from CEUS, SPIES, and white light (WL) endoscopy were correlated with World Small Animal Veterinary Association (WSAVA) endoscopy and histology scores and vessel density as determined by immunohistochemistry for von Willebrand factor (vWF). Automated linear modeling was used to determine predictors of endoscopic and histologic severity. RESULTS: Duodenal histology correlated with SPIES data (area percentage value, rho = 0.424, P = .04). White light endoscopy parameters correlated with SPIES parameters in the duodenum. Colonic histology correlated positively with CEUS, whereas colonic CEUS parameters correlated inversely with vWF expression. Several duodenal parameters combined predicted duodenal histology scores to a level of 73.4%. For the colon, 2 parameters contributed more than others to 73.1%. CONCLUSION AND CLINICAL IMPORTANCE: Minimally invasive CEUS and SPIES appear feasible to assess intestinal perfusion in CIE. Use of SPIES endoscopy may be promising for assessing small intestinal inflammation, whereas CEUS could be used to assess colonic perfusion and inflammation. Both techniques need to be investigated further for their clinical utility.

A Computed Tomographic Assessment of Osteitis of Sinus Bony Structures in Horses With Sinonasal Disorders.

Background: Computed tomographic (CT) imaging has shown some horses with sinonasal diseases to have changes in their sinus bony structures. Scintigraphic and clinical evidence of sinus osteitis have also been reported. However, no study has objectively examined for the presence and degree of osteitis in equine sinonasal disease. Objectives: To assess for the presence and extent of osteitis of sinus-related bony structures by examination of CT images of horses with clinically and sinoscopically confirmed unilateral sinonasal disease. Study Design: Retrospective examination of CT images of horses with confirmed, mainly chronic (>2 month duration) unilateral sinus disease of different etiologies. Methods: Bone thickness at designated sites of the maxillary bone (n = 3), frontal bone (n = 1), infraorbital canal (n = 2), and bony nasolacrimal duct (n = 1) were measured, as were the maximal diameters of the infraorbital canal and the bony nasolacrimal duct on both affected and control sides. Maxillary bone density (in Hounsfield Units) was also assessed bilaterally. Bone thickness was compared between affected and controlled sides using paired statistical tests. Results: Bone was significantly thicker in the affected sinuses compared to the control sides at the three maxillary bone sites (all, P < 0.001) and at both infraorbital bone sites (both, P < 0.001), but not at the two most dorsal sites examined, i.e. frontal bone (P = 0.188) and bony nasolacrimal duct (P = -0.260) sites. Infraorbital canal and bony nasolacrimal duct diameters were significantly wider in the affected as compared to the control sides (P < 0.001 and P = 0.002, respectively). Maxillary bone density did not differ significantly between the affected (mean = 1,075 HU, SD = 230.01) and control (mean = 1,100, SD = 200.71) sides (t (58) = -1.03, P = 0.306). Main Limitations: Possible variation in selecting measurement sites. Variation in the severity and chronicity of sinonasal disease between horses. Conclusions: Osteitis and enlargement of paranasal bony structures commonly occurs in horses with sinonasal disease and can explain the clinical presence of ipsilateral diffuse soft tissue facial swelling, epiphora, and scintigraphic evidence of bone inflammation in sinonasal disease.

Effect of Stifle Flexion Angle on the Repeatability of Real-Time Elastosonography of the Patellar Ligament in Medium- to Large-Breed Dogs.

OBJECTIVE: The aims of this study were to describe the elastosonographic findings of the patellar ligament in healthy dogs >15 kg in different positions and determine the most appropriate stifle angle to perform elastosonography of the patellar ligament. STUDY DESIGN: Eighteen clinically healthy dogs, weighing >15 kg, were prospectively recruited. B-mode ultrasound and real-time elastosonography of both patellar ligaments were performed on days 0 and 14. Elastosonography examinations were performed with the stifle in four positions: standing position, lateral recumbency with the stifle positioned at 135 degrees extension and in full passive flexion and extension. RESULTS: The percentage hardness of the patellar ligament was significantly lower when the elastosonographic examination was performed with the dog standing, compared with the other positions (p < 0.005). The variability in the elastosonography readings for each stifle position was lowest when the dog was standing (89.32%). CONCLUSION: Elastosonography is a feasible technique for evaluating the elasticity of the normal canine patellar ligament in dogs >15 kg and would be a useful technique for investigating the mechanical changes within the patellar ligament following stifle surgery. Elastosonography of the patellar ligament should be performed with the dog standing to provide the most accurate elastosonograms with lowest variability between readings.

The use of the geometric morphometric method to illustrate shape difference in the skulls of different-aged horses.

The geometric morphometrics method (GMM) is a technique to study scale and shape relationships of structures using Cartesian geometric coordinates rather than linear, areal (of area), or volumetric variables. GMM has been of great value in many biological studies, but does not appear to have been used to examine equine skulls.In this exploratory study, twenty-nine normal equine heads of three different age groups: <5 years old (N = 9), 6-15 years old (N = 10) and > 16 years old (N = 10) were examined.Computed tomography (CT) bone window DICOM images were reconstructed into isosurfaces (3-dimensional contoured surfaces), onto which landmarks were added using Stratovan Checkpoint® software. Data from 29 landmarks were analysed using MorphoJ analysis, which applies a Procrustes fit, prior to reducing data dimensionality through principal component (PC) analysis. PCs with and without allometry were considered. Allometric shape described by PC1 accounted for 27% of variance. Loading pertaining to: the pterygoid process, bilaterally; caudal aspect of hard palate; tip of nasal bone; ethmoid sinuses, bilaterally; caudal aspect of the ventral conchal bulla, bilaterally and caudal aspect of the vomer bone suggest that these anatomical structures are predictive of age group. When allometric effects (shape variation explained by size) were removed, PC1 was unable to distinguish horses by age group. Allometric shape differences could distinguish the youngest versus the two older age groups. The potential applications of GMM in equine diagnostic imaging are wide ranging and include the investigation of changes in the equine skull with respect to genetics and characterisation of conformation-related diseases affecting the teeth, jaws and sinonasal compartments.