[Ventral stabilization of an atlantoaxial subluxation with screws and polymethylmetacrylat in a miniature Yorkshire Terrier]. / Ventrale Stabilisation einer atlantoaxialen Subluxation mittels Schrauben und Polymethylmetacrylat bei einem Miniatur-Yorkshire-Terrier.

A 6-month-old female Miniature Yorkshire Terrier with a bodyweight of 1.1 kg was presented due to non-ambulatory tetraparesis. Latero-lateral radiographs showed an increased space between the spinal process of the axis and the dorsal arch of the atlas, with craniodorsal displacement and rotation of the body of the axis in relation to the atlas. Computed tomography also revealed a craniodorsal displacement of the axis in relation to the atlas with an unfusioned dens. Initially, a dorsal surgical approach was chosen and an intermuscular suture pattern was used attempting to achieve reduction of the subluxation. Radiographically and clinically the result however was not acceptable. In a second surgery, a ventral stabilization technique (using 4 1.5 mm screws in atlas and axis with polymethylmetacrylate) was performed. The achieved repositioning was considered acceptable. The dog was provided with a cervical bandage for 6 weeks. Clinically, the patient improved progressively and remains free of clinical signs up to the time of manuscript preparation, 37 months post-operatively.

Plexiform Vasculopathy in Feline Cervical Lymph Nodes.

Plexiform vasculopathy refers to an endothelial proliferative disorder affecting cervical or inguinal lymph nodes of cats. The cause of this disorder and the origin of the proliferating endothelial cells are still unknown. In 4 cats with a history of a slowly growing, well-demarcated, nonpainful mass adjacent to the thyroid gland, an enlarged dark brown to red lymph node was removed. Histologically, the lymph nodes showed severe loss of lymphoid tissue with accumulations of erythrocytes. In addition, networks of capillary structures with well-differentiated endothelial cells on a collagen-rich stroma were observed, consistent with benign plexiform vasculopathy. Immunohistochemistry revealed the expression of the vascular endothelial markers CD31 and factor VIII-related antigen. In addition, immunolabeling with a Prox-1 antibody indicated a lymphendothelial origin. With respect to our findings, a lymphendothelial origin has to be considered in cases of intranodal vascular neoplasms.