Comparison of Two Surgical Techniques for the Treatment of Canine Disc Associated-Cervical Spondylomyelopathy.

Objective: To compare prosthetic disc and vertebral distraction stabilization in dogs with disc-associated cervical spondylomyelopathy (DA-CSM). Study Design: A retrospective clinical study. Animals: 25 dogs. Methods: Dogs presenting with clinical signs and MRI findings compatible with DA-CSM underwent surgery. Implantation of the Adamo's prosthetic disc (PD) or vertebral distraction-stabilization (DS) with intervertebral cage, ventral locking plates, and dorsal transarticular screws was performed. All dogs were followed-up and evaluated clinically for a minimum of 1 year and radiographically for at least 3 months. In particular, we focused on the evaluation of subsidence (the degree of vertebral collapse). Results: Twenty-five dogs were enrolled: 12 with PD implantation and 13 with DS implantation. Of these, 24 dogs were followed-up at 1 year. Overall, 12 dogs improved (4 PD and 8 DS), eight were stable (4 PD and 4 DS), and four deteriorated (3 PD and 1 DS). Deterioration was more common in PD cases, especially soon after surgery. In a few PD cases, a second surgery was necessary. The most common complication in dogs with DS was discospondylitis. Subsidence was detected in 11 PD and 7 DS dogs. Subsidence was more severe and occurred sooner after surgery in PD cases compared to DS cases. DS cases were more prone to clinical improvement and less prone to subsidence than PD cases in this study. However, the statistical evidence was weak owing to the small sample size. Conclusion: The preliminary results suggest that prosthetic disc implantation is more prone to clinical and radiographic failures than distraction stabilization. Clinical Relevance: The DS technique is a valuable surgical option for treating dogs with DA-CSM, with favorable short- and long-term clinical and radiographic outcomes.

Microcystic meningioma of the fourth ventricle in a dog.

A 5-year-old female cross-breed dog was presented with a 1-month history of progressive changes in the posture of the head and in the gait. At neurological examination the dog showed a central vestibular syndrome lateralized to the left. MRI showed a space occupying lesion within the fourth ventricle, characterized by iso- to hypointensity in T1 and hyperintensity in T2 with a heterogeneous contrast uptake. Histologically, a neoplasia composed of meningothelial cells forming compact whorls with slight atypia, and stellate cells delimitating microcysts containing eosinophilic fluid was observed. Neoplastic cells were positive for vimentin and negative for GFAP and FVIII. A diagnosis of intraventricular microcystic meningioma was achieved. Intraventricular meningiomas in dogs are rarely encountered and reports of meningiomas within the fourth ventricle have not yet been described. Although choroid plexus tumor is the most frequent neoplasia localized in the fourth ventricle, intraventricular meningioma should be included in the differential diagnoses.

Squash-prep cytology in the diagnosis of canine and feline nervous system lesions: a study of 42 cases.

BACKGROUND: The increased sophistication of imaging techniques in veterinary medicine allows the detection of a wide variety of intracranial and intraspinal lesions; however, imaging often does not provide a definitive diagnosis for nervous system (NS) lesions. Cytology is emerging as a useful diagnostic tool for obtaining a fast and accurate assessment of NS lesions, but little information is available for dogs and cats. OBJECTIVES: The purpose of this study was to assess the accuracy of cytologic evaluation of squash samples from NS lesions in dogs and cats and to consider cytology-based diagnostic guidelines and sources of misdiagnosis. METHODS: Cytologic specimens from masses localized in the central and peripheral NS taken during surgery or postmortem examination were classified into 3 groups according to the final histopathologic diagnosis: Group 1 = completely correct diagnosis, when the cytologic diagnosis and final histologic diagnosis were exactly correlated; Group 2 = partial correlation, when the cytologic diagnosis only partially correlated with the final histologic diagnosis, and Group 3 = no correlation, when the cytologic diagnosis was incorrect and there was no correlation with the general histologic type of lesion. The diagnostic accuracy of cytopathology was calculated by considering the histopathologic diagnosis as the "gold standard," and calculating a 95% confidence interval (CI). RESULTS: A total of 42 animals (33 dogs and 9 cats) were included in the study. The cytologic diagnoses were classified in Group 1 for 32 cases (76%; 95% CI 0.63-0.89), in Group 2 for 6 cases (14%; 95% CI 0.04-0.25), and in Group 3 for 4 cases (10%; 95% CI 0.006-0.18). Considering both complete and partial correlation as an adequate result, cytologic diagnosis was satisfactory in 90% of biopsies. CONCLUSIONS: Although the current series of cases is relatively small, cytologic evaluation of squash preparations can be considered a fairly accurate and reliable tool in the diagnosis of NS lesions.

Papillary meningioma in the dog: A clinicopathological case series study.

Papillary meningioma (PM) is one of the most aggressive variants of meningioma in humans and classified as grade III by WHO system. To date, the biological behavior of PM is still not clear in dogs. This study investigated the correlation between histopathological findings of 16 canine PMs and follow up data. Moreover, the expression of doublecortin, E-cadherin, and N-cadherin was investigated by immunohistochemistry. The supratentorial compartment resulted the most common involved. Despite the low grade of histological malignancy, 87.5% of dogs that underwent surgery experienced tumor recurrence. Intratumoral necrosis was observed in a strict correlation with malignancy histological parameter and tumor recurrence. The post-surgery mean survival time was much lower than thus observed in the most common histological subtypes. This data were also confirmed in dogs that received a conservative treatment alone. Tumors with a severe clinical behavior showed a high N-cadherin expression versus a low or absent E-cadherin expression.

A preliminary investigation of the relationship between the "moment of resistance" of the canine spine, and the frequency of traumatic vertebral lesions at different spinal levels.

The aims of this work were to re-evaluate the moments of resistance (MoRs) of the vertebral column proposed by Slijper (1946) in the dog and to study the relationship between the MoRs and the frequency distribution of vertebral traumas in the same species. The spine (C2-L7) of four dogs was measured to obtain MoRs and subsequently scanned with a dual-energy X-ray absorptiometer (DXA). These findings were then analysed retrospectively the frequency distribution of canine vertebral fractures and luxations, diagnosed radiographically at a referral practice. The highest percentage of vertebral injuries affected the T9-L7 tract. This study confirmed that this segment was characterized by a rising trend of the MoR curves and presumably bore the major bending forces. The significant correlation between T9-L1 MoRs and DXA values supports the Slijper's hypothesis suggesting the posterior thoracic region as the weakest segment of the body-axis.