Martin Sullivan

Use of magnetic resonance imaging for morphometric analysis of the caudal cranial fossa in Cavalier King Charles Spaniels

OBJECTIVE To perform morphometric analysis of the caudal cranial fossa in Cavalier King Charles Spaniels (CKCSs), to assess the relationship between caudal fossa dimensions and the frequency of magnetic resonance imaging (MRI) features of occipital abnormalities in CKCSs (with and without syringomyelia), and to compare caudal cranial fossa measurements in CKCSs with measurements of 2 groups of mesaticephalic dogs. ANIMALS 70 CKCSs and 80 mesaticephalic (control) dogs. PROCEDURES Dogs were placed into 4 groups as follows: Labrador Retrievers (n = 40), spaniel-type dogs (40; English Springer Spaniels and Cocker Spaniels), CKCSs with syringomyelia (55), and CKCSs without syringomyelia (15). Multiple morphometric measurements (linear, angular, and area) were obtained from cranial midsagittalT2-weighted magnetic resonance images including the brain and cervical portion of the spinal cord. Several specific MRI findings were also recorded for CKCSs that appeared to affect the occipital bone and cervicomedullary junction. RESULTS No significant difference was identified among breeds in control groups and between sexes in any of the groups for all morphometric measurements. Significant differences were identified in CKCSs, compared with mesaticephalic dogs, in the area of the caudal cranial fossa and for several linear measurements that reflected the length of the ventral aspect of the occipital bone. These differences were greater in CKCSs with syringomyelia. All CKCSs had abnormalities in occipital bone shape. CONCLUSIONS AND CLINICAL RELEVANCE CKCSs had a shallower caudal cranial fossa and abnormalities of the occipital bone, compared with those of mesaticephalic dogs. These changes were more severe in CKCSs with syringomyelia.

Comparison of ultrasonography, radiography and a single computed tomography slice for the identification of fluid within the canine tympanic bulla.

Fluid accumulation within the tympanic bulla (TB) is an important diagnostic indicator in clinical cases of canine otitis media although its identification can be a challenge using currently available imaging techniques. The aim of this study was to compare ultrasound with radiography and a single computed tomography (CT) slice for the identification of fluid within the TB of canine cadavers. A random number of TB in 66 cadavers were filled with ultrasound gel. Rostrocaudal open mouth (RCdoM) radiographs and CT images were interpreted by 2 blinded radiologists and ultrasound examinations were performed by 2 blinded sonographers. The heads were then frozen and sectioned to confirm the contents of each TB. Although CT remained the most accurate method, comparable results were obtained by one of the sonographers and even the inexperienced sonographer produced results superior to radiography. Ultrasound has several advantages over the other imaging techniques and this study suggests that it may have an application in the investigation of canine otitis media although further work in live animals would be required to confirm this.

Evaluation of once daily treatment with cyclosporine for anal furunculosis in dogs

Twenty.four dogs with anal furunculosis were treated with cyclosporine once daily for 13 weeks at dosages of 1.5, 3.0, 5.0 or 7.5 mg/kg, and re.examined after six and 12 months. After 13 weeks the disease in six of the dogs was in remission, 11 were controlled or improved and seven had failed to respond. The response of the dogs given the highest dose was significantly better than the response of the other groups taken together (P<0.01 4), and better than the responses of the groups given 1.5 mg/kg and 5 mg/kg (P<0.05). The dogs improved clinically during the treatment, most rapidly during the first five weeks. Of the six dogs that were in remission after 13 weeks, three relapsed after one, two and six months. The 1 1 dogs that were improved or controlled after 13 weeks were either left untreated or were continued on cyclosporine medication for one to three months at a dosage of 1.5 to 7.5 mg/kg; the disease went into remission in four cases and remained controlled in the other seven, but four of the 1 1 cases relapsed during the 12 months following the treatment. The side effects observed included increased coat turnover and transient vomiting.

Bilateral overlapping mucosal single-pedicle flaps for correction of soft palate defects

The clinical outcomes of bilateral overlapping single-pedicle flaps used for repair of congenital cleft of the soft palate in 10 animals (nine dogs and one cat) are reported. Six animals had concurrent cleft of the hard palate repaired using a previously described mucoperiosteal flap technique. Animals ranged from one to 13 months of age at surgery, with follow-up ranging from two to 12 months. Healing was uncomplicated in all cases and provided excellent functional results.

Gastric disease in the dog and cat

The physiology of the normal gastric defence mechanisms in the dog and cat is reviewed to emphasize the routes by which drugs can be used to protect the gastric mucosa. The action of the main anti-ulcer and pro-kinetic drugs are discussed in relation to the diseases that they may be used to treat. Gastric disease in the form of gastric dilatation/volvulus, chronic vomiting without obstruction and gastric outflow disease are described from the point of view of diagnosis and treatment.

Ultrasound imaging of the canine tympanic bulla

A procedure for imaging the canine tympanic bulla, external ear canal and adjacent structures using currently available ultrasound equipment was established. Lateral and ventral transducer positions were identified for this purpose and a 6.5 MHz curvilinear transducer was considered to be optimal. The sonographic appearance of these structures in cadavers and live dogs unaffected by ear disease is documented. Fluid was introduced into the tympanic bullae of the cadavers and its presence could be identified through the bony wall of the bulla. The ability of ultrasound to differentiate between gas and fluid within the bulla has important clinical implications as this is a common occurrence in dogs with middle ear disease. Ultrasound has several advantages over other imaging modalities and the examination procedure was well tolerated by unsedated dogs.

Effect of brachycephalic, mesaticephalic, and dolichocephalic head conformations on olfactory bulb angle and orientation in dogs as determined by use of in vivo magnetic resonance imaging

OBJECTIVE To determine the effect of head conformation (brachycephalic, mesaticephalic, and dolichocephalic) on olfactory bulb angle and orientation in dogs by use of in vivo MRI. ANIMALS 40 client-owned dogs undergoing MRI for diagnosis of conditions that did not affect skull conformation or olfactory bulb anatomy. PROCEDURES For each dog, 2 head conformation indices were calculated. Olfactory bulb angle and an index of olfactory bulb orientation relative to the rest of the CNS were determined by use of measurements obtained from sagittal T2-weighted MRI images. RESULTS A significant negative correlation was found between olfactory bulb angle and values of both head conformation indices. Ventral orientation of olfactory bulbs was significantly correlated with high head conformation index values (ie, brachycephalic head conformation). CONCLUSIONS AND CLINICAL RELEVANCE Low olfactory bulb angles and ventral olfactory bulb orientations were associated with brachycephalia. Positioning of the olfactory bulbs, cribriform plate, and ethmoid turbinates was related. Indices of olfactory bulb angle and orientation may be useful for identification of dogs with extremely brachycephalic head conformations. Such information may be used by breeders to reduce the incidence or severity of brachycephalic-associated diseases.

Computed Tomographic Features of Incomplete Ossification of the Canine Humeral Condyle

OBJECTIVES To describe computed tomographic (CT) features of canine elbows with incomplete ossification of the humeral condyle (IOHC) and investigate co-existing incongruence in the elbow joint. STUDY DESIGN Case control study. ANIMALS Dogs with IOHC (n=20; 38 elbows) and 25 normal elbows. METHODS Elbows with IOHC and normal elbows were assessed by CT. Standardized dorsal and sagittal reconstructions were created at 3 levels using image analysis software to obtain single measurements of the humero-radial and humero-ulnar joint spaces. On dorsal plane reconstructions, joint space measurements were obtained at the center point of the humero-radial and humero-ulnar articulations. Joint incongruity was defined as the difference between the humero-radial and the humero-ulnar joint spaces. RESULTS Nineteen dogs (95%), all Spaniel breeds, had either bilateral IOHC demonstrable as a saw-toothed intercondylar complete or incomplete hypoattenuating defect with hyperattenuating margins, or IOHC with contralateral humeral condylar fracture (HCF). Joint incongruity values for IOHC were compared with those of normal elbows. Significant differences were noted at the levels of the medial coronoid apex (P<.0001) and base (P<.004) indicative of humero-ulnar incongruence. Evidence of medial coronoid disease in 10 elbows (26%) and degenerative joint disease in 30 elbows (79%) was also found. CONCLUSIONS Presence of elbow incongruence may be an underlying factor in failure of ossification centers to fuse leading to IOHC. CLINICAL RELEVANCE IOHC is clearly defined by CT, and it should be considered in larger Spaniel breeds, with a chronic forelimb lameness or HCF.

MAGNETIC RESONANCE IMAGING FEATURES OF DISCOSPONDYLITIS IN DOGS

The diagnosis of discospondylitis is based mainly on diagnostic imaging and laboratory results. Herein, we describe the magnetic resonance imaging (MRI) findings in 13 dogs with confirmed discospondylitis. In total there were 17 sites of discospondylitis. Eleven (81.1%) of the dogs had spinal pain for >3 weeks and a variable degree of neurologic signs. Two dogs had spinal pain and ataxia for 4 days. Radiographs were available in nine of the dogs. In MR images there was always involvement of two adjacent vertebral endplates and the associated disk. The involved endplates and adjacent marrow were T1-hypointense with hyperintensity in short tau inversion recovery (STIR) images in all dogs, and all dogs also had contrast enhancement of endplates and paravertebral tissues. The intervertebral disks were hyperintense in T2W and STIR images and characterized by contrast enhancement in 15 sites (88.2%). Endplate erosion was present in 15 sites (88.2%) and was associated with T2-hypointense bone marrow adjacent to it. In two sites (11.8%) endplate erosion was not MR images or radiographically. The vertebral bone marrow in these sites was T2-hyperintense. Epidural extension was conspicuous in postcontrast images at 15 sites (88.2%). Spinal cord compression was present at 15 sites (88.2%), and all affected dogs had neurologic signs. Subluxation was present in two sites (11.8%). MRI shows characteristic features of discospondylitis, and it allows the recognition of the exact location and extension (to the epidural space and paravertebral soft tissues) of the infection. Furthermore, MRI increases lesion conspicuity in early discospondylitis that may not be visualized by radiography.

Adult Learning in Veterinary Education: Theory to Practice

This paper argues the case for the increased application of adult learning principles to veterinary education. It encapsulates evidence from the United Kingdom, Europe, North America, and Australia to explain why it has taken veterinary schools so long to transform their curricula to best facilitate the development of lifelong learning skills, such as independent and self-directed learning, problem solving, and critical thinking. Despite the variation in training programs in these different regions, the paper identifies common issues-conflicting educational paradigms and the need for faculty development-and ultimately concludes that professional and continuing education should be viewed as a continuous process, supporting the adult learners cognitive development and facilitated through experiential learning.