Epidemiological aspects of myelography in dogs: 61 cases (2003-2012)

Abstract

Myelography is a radiological contrast examination technique frequently used in the diagnosis of vertebral spine and spinal cord disorders. The procedure involves inserting a needle with subsequent injection of contrast medium, which delimits the spinal cord. The main indication is suspected spinal injuries not visualized on plain radiographs. Myelography is effective in the identification of the location of the lesion but is contraindicated in patients with infectious diseases or who have recently experienced trauma. Advantages of myelography are cost effectiveness in both the examination procedure and maintenance of equipment, and delivery of quality images, compared with other imaging methods in dogs. Disadvantages include a relatively long examination procedure, the need for general anesthesia, and the risk of seizures or death. The aim of this study was to characterize a population of dogs undergoing myelography according to the following factors: Severity of injury, breed, age, sex, reproductive status, diet, weight, previous illnesses, vertebral region evaluated, lesion location in spinal cord or meninges, cause of radiographic signs, and possible complications. The database was created from information in medical records, and included 61 dogs with suspected disorders of the vertebral spine, spinal cord, and/or meninges that underwent myelography at the Unidade Hospitalar para Animais de Companhia of Pontifícia Universidade Católica do Paraná from January 2003 through December 2012. The results indicate that the most common degree of injury severity was Grade 2 (39.34% of the patients). The most prevalent breeds were mixed breed dogs (22.58%) and the dachshund (18.03%). Ages with higher frequency were 6 and 10 years (average, 7.6 years). According to sex and reproductive status, intact male (42.62%) and female (36.06%) dogs were most affected. The commercial (50.82%) and mixed (44.26%) diets were the most common diets. The body weight between 6 and 15 kg (37.70%) was the most significant. Most of the patients showed no previous diseases (73.77%). The thoracolumbar region was the most evaluated (47.22%). Most injuries were extramedullary (62.30%), and the most common cause was intervertebral disc disease (52.38%). The complications of myelography were not significant. It can be seen that the data in our environment tend to be similar to those of the national literature, but international literature is currently focusing on more sensitive tests such as CT and MRI.