Agreement and differentiation of intradural spinal cord lesions in dogs using magnetic resonance imaging.

BACKGROUND: Magnetic resonance imaging is the method of choice for diagnosing spinal cord neoplasia, but the accuracy of designating the relationship of a neoplasm to the meninges and agreement among observers is unknown. OBJECTIVES: To determine agreement among observers and accuracy of diagnosis compared with histology when diagnosing lesion location based on relationship to the meninges. ANIMALS: Magnetic resonance images from 53 dogs with intradural extramedullary and intramedullary spinal neoplasms and 17 dogs with degenerative myelopathy. METHODS: Six observers were supplied with 2 sets of 35 images at different time points and asked to designate lesion location. Agreement in each set was analyzed using kappa (κ) statistics. We tabulated total correct allocations and calculated sensitivity, specificity, and likelihood ratios for location designation from images compared with known histologic location for lesions confined to 1 location only. RESULTS: Agreement in the first set of images was moderate (κ = 0.51; 95% confidence interval [CI], 0.43-0.58) and in the second, substantial (κ = 0.69; 95% CI, 0.66-0.79). In the accuracy study, 180 (75%) of the 240 diagnostic calls were correct. Sensitivity and specificity were moderate to high for all compartments, except poor sensitivity was found for intradural extramedullary lesions. Positive likelihood ratios were high for intradural extramedullary lesions and degenerative myelopathy. CONCLUSIONS AND CLINICAL IMPORTANCE: Overall accuracy in diagnosis was reasonable, and positive diagnostic calls for intradural extramedullary lesions and negative calls for intramedullary lesions are likely to be helpful. Observers exhibited considerable disagreement in designation of lesions relationship to the meninges.

Evaluation of magnetic resonance imaging for the differentiation of inflammatory, neoplastic, and vascular intradural spinal cord diseases in the dog.

Magnetic resonance imaging (MRI) is a common test for dogs with suspected intradural spinal cord lesions, however studies on diagnostic performance for this test are lacking. Objectives of this multi-institutional, retrospective, case-control study were to estimate sensitivity and specificity of MRI for (1) distinguishing between histopathologically confirmed intradural spinal cord disease versus degenerative myelopathy in dogs, (2) categorizing intradural spinal cord diseases as neoplastic, inflammatory, or vascular; and (3) determining tumor type within the etiologic category of neoplasia. Additional aims were to (1) determine whether knowledge of clinical data affects sensitivity and specificity of MRI diagnoses; and (2) report interrater agreement for MRI classification of intradural spinal lesions. Cases were recruited from participating hospital databases over a 7-year period. Three reviewers independently evaluated each MRI study prior to and after provision of clinical information. A total of 87 cases were sampled (17 degenerative myelopathy, 53 neoplasia, nine inflammatory, and eight vascular). Magnetic resonance imaging had excellent (>97.6%) sensitivity for diagnosis of intradural spinal cord lesions but specificity varied before and after provision of clinical data (68.6% vs. 82.4%, P = 0.023). Magnetic resonance imaging had good sensitivity (86.8%) and moderate specificity (64.7-72.5%) for diagnosing neoplasia. Sensitivity was lower for classifying inflammatory lesions but improved with provision of clinical data (48.1% vs. 81.5%, P = 0.015). Magnetic resonance imaging was insensitive for diagnosing vascular lesions (25.0%). Interrater agreement was very good for correctly diagnosing dogs with intradural lesions (ĸ = 0.882-0.833), and good (ĸ = 0.726-0.671) for diagnosing dogs with neoplasia.

Standing placement of transphyseal screw in the distal radius in 8 Thoroughbred yearlings.

This retrospective study describes placement of distal radial transphyseal screws in Thoroughbred yearlings with carpal varus deformities while standing, and identifes short- and long-term complications following the procedure. Data gathered from 2009 to 2013 identified 8 yearlings that met the inclusion criteria. Horses were sedated intravenously and a single 4.5-mm cortical screw was placed in the distal lateral radial physis following application of local anesthetic and surgical preparation of a pre-placed hole. All horses were evaluated weekly after surgery and screw removal was performed standing and under sedation when correction of the angular limb deformity was achieved. The mean time for screw removal was 46 days. No short- or long-term complications were identified. Findings indicate that placing a single transphyseal screw in the lateral aspect of the distal radial physis with the horse standing is a viable option to treat varus angular limb deformity of the carpus in horses.

Placement debout d'une vis transphysaire dans le radius distal chez 8 Thoroughbred âgés d'un an. Cette étude rétrospective décrit le placement d'une vis transphysaire dans le radius distal de chevaux Thoroughbred âgés d'un an ayant des difformités du varus carpien, lorsqu'ils sont debout, et elle identifie les complications à court et à long terme après l'intervention. Les données recueillies de 2009 à 2013 ont identifié 8 chevaux âgés d'un an qui satisfaisaient aux critères d'inclusion. Les chevaux ont été mis sous sédation par intraveineuse et une seule vis corticale de 4,5 mm a été placée dans le cartilage diaphyso-éphysaire après l'application d'anesthésie locale et de la préparation chirurgicale d'un trou pratiqué au préalable. Tous les chevaux ont été évalués une fois par semaine après la chirurgie et l'enlèvement de la vis a été réalisé debout et sous sédation lorsque la correction de la difformité angulaire du membre a été obtenue. Le temps moyen de l'enlèvement des vis était de 46 jours. Aucune complication à court ou à long terme n'a été identifiée. Les résultats indiquent que le placement d'une seule vis transphysaire dans l'aspect latéral du cartilage diaphyso-éphysaire distal radial, lorsque le cheval se tient debout, est une option viable pour traiter la difformité angulaire de type varus du carpe chez les chevaux.(Traduit par Isabelle Vallières).