Plain radiography, myelography, and computerized tomography, alone or in combination, have been used to diagnose neurologic disorders affecting the cervical vertebral column and spinal cord.1 Because of the invasive nature and diagnostic limitations of myelography,2,3 MRI has become a popular diagnostic tool for use in evaluation of the spinal cord. Magnetic resonance imaging is an attractive diagnostic alternative because it is a noninvasive technique, involves no radiation, is not known to be associated with any major adverse effects, and provides superior resolution of the anatomy, particularly of soft tissue structures, in multiple anatomic planes.4 Magnetic resonance imaging can be useful in evaluating and diagnosing a variety of disorders of the cervical spinal cord and vertebral column of dogs.5–7 The high sensitivity of MRI can cause problems in interpretation of images because nonimportant lesions become evident.8 One canine8 and several human9–15 studies have revealed the existence of cervical spinal cord compression in subjects without clinical signs. However, little is known about the clinical relevancy, progression, and prognosis for these cervical spinal cord compressions that do not cause clinical signs and whether they would justify meticulous clinical and MRI monitoring or even early surgical decompression before clinical manifestation of a neurologic deficit. To determine the importance of abnormalities detected during MRI examinations, the spectrum and frequency of structural abnormalities that may not cause problems must be considered. At this time, little is known about this subject in veterinary medicine.
In the study reported here, the low-field MRI features of the cervical vertebral column and spinal cord, with special emphasis on the caudal portion of the cervical region, of clinically normal Doberman Pinschers and Foxhounds were investigated. It was hypothesized that structural abnormalities existed in a substantial portion of the study population and that breed, age, and sex could influence the development and severity of these findings. Furthermore, it was hypothesized that the development of certain abnormalities could be associated with the location of the assessed intervertebral disk space. This study was part of a larger investigation of the diagnosis and treatment of disk-associated wobbler syndrome in dogs.
Magnetic resonance imaging
Magnet, Airis Mate, Hitachi, Japan.
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