Contribuições radiográficas no diagnóstico e no planejamento cirúrgico de afecções da coluna vertebral em cães

Abstract

Conventional radiographs and myelography are still used in veterinary medicine to diagnose certain diseases affecting the spinal column and spinal cord. However, they are being replaced by more advanced imaging modalities such as computed tomography and magnetic resonance imaging. Advanced imaging exams are often recommended in addition to conventional methods because they allow for a more precise evaluation of different structures and tissues. It is undeniable that these are the most suitable methods for diagnosing neurological diseases, and there is no question about the significant advances in research related to these techniques. However, the reality still observed in veterinary medicine is that a large portion of patients do not have access to these technological advancements, either due to equipment unavailability or financial restrictions of the owners. The aim of this thesis was to use digital radiography to improve the accuracy of diagnosing dogs with intervertebral disc extrusion (IVDE), especially those with extensive spinal cord edema, and to assist in planning surgeries to stabilize the lumbar vertebral column of dogs for the insertion of pins and/or screws, thus enabling treatment with diagnostic aid for patients who do not have access to advanced imaging exams. The thesis contains two studies. The first aimed to propose radiographic measurements of canine lumbar vertebral bodies (L1 to L6) from cadavers capable of predicting, through a mathematical models, the length of insertion of bicortical pins into the vertebral bodies. The second aimed to evaluate the accuracy of conventional myelographic exams, including a lateral radiographic image acquisition during contrast injection into the subarachnoid space (lateral projection of dtnamic study) at the location of the compressive lesion in dogs with thoracolumbar and lumbar IVDE. We conclude that digital radiography remains a useful diagnostic tool in neuroimaging when advanced modalities are unavailable. Surgical planning for implant insertion in lumbar vertebral bodies is feasible, using mathematical models to predict the length of implant insertion through radiographic measurements. The inclusion of lateral projection in dynamic myelography exams improves diagnostic efficacy in dogs with thoracolumbar intervertebral disc extrusion, particularly in those with extensive spinal cord edema, aiding in the identification of the site of spinal cord compression.