title: CLINICAL AND MAGNETIC RESONANCE IMAGING CHARACTERISTICS OF THORACOLUMBAR INTERVERTEBRAL DISK EXTRUSIONS AND PROTRUSIONS IN LARGE BREED DOGS.
abstract: Treatment recommendations differ for dogs with intervertebral disk extrusion vs. intervertebral disk protrusion. The aim of this retrospective, cross-sectional study was to determine whether clinical and magnetic resonance imaging (MRI) variables could be used to predict a diagnosis of thoracolumbar intervertebral disk extrusion or protrusion in dogs. Dogs were included if they were large breed dogs, had an MRI study of the thoracolumbar or lumbar vertebral column, had undergone spinal surgery, and had the type of intervertebral disk herniation (intervertebral disk extrusion or protrusion) clearly stated in surgical reports. A veterinary neurologist unaware of surgical findings reviewed MRI studies and recorded number, location, degree of degeneration and morphology of intervertebral disks, presence of nuclear clefts, disk space narrowing, extent, localization and lateralization of herniated disk material, degree of spinal cord compression, intraparenchymal intensity changes, spondylosis deformans, spinal cord swelling, spinal cord atrophy, vertebral endplate changes, and presence of extradural hemorrhage. Ninety-five dogs were included in the sample. Multivariable statistical models indicated that longer duration of clinical signs (P = 0.01), midline instead of lateralized disk herniation (P = 0.007), and partial instead of complete disk degeneration (P = 0.01) were associated with a diagnosis of intervertebral disk protrusion. The presence of a single intervertebral herniation (P = 0.023) and dispersed intervertebral disk material not confined to the disk space (P = 0.06) made a diagnosis of intervertebral disk extrusion more likely. Findings from this study identified one clinical and four MRI variables that could potentially facilitate differentiating intervertebral disk extrusions from protrusions in dogs.
authors.affiliation: Department of Clinical Science and Services, Royal Veterinary College, University of London, North Mymms, Hertfordshire, AL97TA, Hatfield, UK.
authors.forename: Sergio A
authors.initials: SA
authors.lastname: Gomes
authors.affiliation: Department of Clinical Science and Services, Royal Veterinary College, University of London, North Mymms, Hertfordshire, AL97TA, Hatfield, UK.
authors.forename: Holger A
authors.initials: HA
authors.lastname: Volk
authors.affiliation: Department of Clinical Science and Services, Royal Veterinary College, University of London, North Mymms, Hertfordshire, AL97TA, Hatfield, UK.
authors.forename: Rowena Ma
authors.initials: RM
authors.lastname: Packer
authors.affiliation: Department of Clinical Science and Services, Royal Veterinary College, University of London, North Mymms, Hertfordshire, AL97TA, Hatfield, UK.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Kenny
authors.affiliation: Department of Clinical Science and Services, Royal Veterinary College, University of London, North Mymms, Hertfordshire, AL97TA, Hatfield, UK.
authors.forename: Elsa
authors.initials: E
authors.lastname: Beltran
authors.affiliation: Department of Clinical Science and Services, Royal Veterinary College, University of London, North Mymms, Hertfordshire, AL97TA, Hatfield, UK.
authors.forename: Steven
authors.initials: S
authors.lastname: De Decker
mesh_terms: D000818:Animals; D003430:Cross-Sectional Studies; D004283:Dog Diseases / Q000000981:diagnostic imaging*; D004285:Dogs; D005260:Female; D055959:Intervertebral Disc Degeneration / Q000000981:diagnostic imaging / Q000662:veterinary*; D007405:Intervertebral Disc Displacement / Q000000981:diagnostic imaging / Q000662:veterinary*; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000662:veterinary*; D008297:Male; D012189:Retrospective Studies; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology*
keywords: disk herniation; disk prolapse; intervertebral disk; intervertebral disk disease