Successful Surgical Resection of an Ependymal Cyst in the Fourth Ventricle of a Dog.

Ependymal cysts represent congenital brain malformations rarely described in human medicine, where surgical resection is the treatment of choice. In veterinary medicine, only three cases have been previously reported, with one partially resected with surgery. A 6 yr old entire male American Staffordshire terrier was referred with a 4 mo history of incoordination and collapsing episodes with extensor rigidity. Neurological examination localized the lesion to the left central vestibular system and cerebellum. A brain computed tomography scan showed a hypoattenuating lesion with peripheral contrast enhancement in the fourth ventricle consistent with a cyst and secondary hydrocephalus. Treatment with prednisone was initiated, but despite an initial improvement, neurologic signs recurred and a suboccipital craniectomy to remove the cyst was performed. The cyst was first drained, and the capsule was carefully resected. The histopathological evaluation revealed a simple cubic to cylindrical epithelium with apical cilia and loose surrounding fibrillar tissue consistent with an intraventricular ependymal cyst. Four and a half years after surgery, the dog only shows short episodes of balance loss when turning abruptly but is otherwise neurologically normal. To the authors' knowledge, this is the first reported ependymal cyst in the fourth ventricle of a dog with successful surgical resection.

Use of Three-Dimensional Printing Models for Veterinary Medical Education: Impact on Learning How to Identify Canine Vertebral Fractures.

Vertebral fractures and luxations are common causes of neurological emergencies in small-animal patients. The objective of this study was to evaluate the impact of three-dimensional printing (3Dp) models on how veterinary students understand and learn to identify canine spinal fractures and to compare 3Dp models to computed tomography (CT) images and three-dimensional CT (3D-CT) reconstructions. Three spinal fracture models were generated by 3Dp. Sixty first-year veterinary students were randomized into three teaching module groups (CT, 3D-CT, or 3Dp) and asked to answer a multiple-choice questionnaire with 12 questions that covered normal spinal anatomy and the identification of vertebral fractures. We used four additional questions to evaluate the overall learning experience and knowledge acquisition. Results showed that students in the 3Dp group performed significantly better than those in the CT (p < .001) and the 3D-CT (p < .001) groups. Students in the 3Dp and 3D-CT groups answered all questions more quickly than the CT group (3Dp versus CT, p < .001; 3D-CTversus CT, p < .001), with no significant differences between the 3Dp and 3D-CT groups (p = .051). Only the degree of knowledge acquisition that the students considered they had acquired during the session showed significant differences between groups (p = .01). In conclusion, across first-year veterinary students, 3Dp models facilitated learning about normal canine vertebral anatomy and markedly improved the identification of canine spinal fractures. Three-dimensional printing models are an easy and inexpensive teaching method that could be incorporated into veterinary neuroanatomy classes to improve learning in undergraduate students.

Meningioma and glioma as the first collision brain tumour reported in small animals.

We describe the clinical and pathological features of a brain collision tumour consisting of a fibrous meningioma and an anaplastic oligoastrocytoma in a 14-year-old male neutered French Bulldog. Computed tomography of the brain revealed a poorly defined, intra-axial lesion affecting the left frontal lobe. Following euthanasia, histological examination showed an anaplastic oligoastrocytoma invading the brain parenchyma and an adjacent fibrous meningioma. As synchronous intracranial tumours are rare in animals, the aims of this report are to describe the clinical, imaging and histopathological features of an intracranial collision tumour in a dog and highlight the importance of a complete histopathological study despite the imaging findings.

Diagnosis and management of lumbar Aspergillus spp. discospondylitis using intraoperative cytology and external stabilization in a dog with disseminated infection.

Background: Discospondylitis is an infection of the intervertebral disc and adjacent vertebral endplates. The infectious agent is most commonly a bacterial organism and fungal causes are uncommon. Case Description: A 1.5-year-old female entire pug was referred with a 6-week history of right head tilt and progressive non-ambulatory paraparesis. On neurological examination, right facial paralysis and mid and caudal lumbar pain were also detected. Magnetic resonance imaging and computed tomography of the head and spine were performed 3 weeks apart. Findings were consistent with osteolysis of the petrous temporal bone and L2-L3 and L5-L6 vertebral subluxation caused by discospondylitis and osteomyelitis. Disseminated aspergillosis was diagnosed following biopsy and stabilization using an external skeletal spinal fixator. Voriconazol was administered as a medical treatment after surgery. The dog died 3 months later without failure of the construct. Conclusion: To the authors' knowledge, this is the first report using an external fixator for fungal lumbar discospondylitis. The use of an external skeletal spinal fixator should be considered when choosing the surgical technique.

Long-term follow-up of surgical resection alone for primary intracranial rostrotentorial tumors in dogs: 29 cases (2002-2013).

Intracranial neoplasia is frequently encountered in dogs. After a presumptive diagnosis of intracranial neoplasia is established based on history, clinical signs and advanced imaging characteristics, the decision to treat and which treatment to choose must be considered. The objective of this study is to report survival times (ST) for dogs with intracranial meningiomas and gliomas treated with surgical resection alone (SRA), to identify potential prognostic factors affecting survival, and to compare the results with the available literature. Medical records of 29 dogs with histopathologic confirmation of intracranial meningiomas and gliomas treated with SRA were retrospectively reviewed. For each dog, signalment, clinical signs, imaging findings, type of surgery, treatment, histological evaluation, and ST were obtained. Twenty-nine dogs with a histological diagnosis who survived >7 days after surgery were included. There were 15 (52%) meningiomas and 14 (48%) gliomas. All tumors had a rostrotentorial location. At the time of the statistical analysis, only two dogs were alive. Median ST for meningiomas was 422 days (mean, 731 days; range, 10-2735 days). Median ST for gliomas was 66 days (mean, 117 days; range, 10-730 days). Kaplan-Meier analysis indicated that ST was significantly longer for meningiomas than for gliomas (P<0.05). A negative correlation between the presence of a midline shift and ST (P=0.037) and ventricular compression and ST (P=0.038) was observed for meningiomas. For gliomas, there were no significant associations between ST and any of the variables evaluated. In conclusion, the results of this study suggest that, for dogs that survived >7 days postoperatively, SRA might be an appropriate treatment, particularly for meningiomas, when radiation therapy is not readily available. Also, the presence of midline shift and ventricular compression might be negative prognostic factors for dogs with meningiomas.