DOI: 10.5061/dryad.kprr4xhj9
title: Cone beam computed tomographic myelography in horses with cervical vertebral compressive myelography

description: Background: While computed tomographic (CT) myelography is increasingly
 available and has been evaluated in alive horses, objective criteria for
 diagnosing cervical vertebral compressive myelopathy (CVCM) are lacking.
 Objectives: Establish morphometric dimensions of cervical vertebral canal
 and spinal cords from horses with CVCM and compare those to unaffected
 horses with the use of cone beam CT (CBCT). Study design: Prospective
 observational study. Methods: Four control horses and ten horses with CVCM
 underwent diagnostic imaging and histopathology. Morphometric measurements
 were obtained from cervical radiographs and radiographic and CBCT
 myelography. Receiver operating characteristic curves were generated to
 establish thresholds of measurements. Results: Intravertebral sagittal
 ratios were significantly different between CVCM and control horses.
 Dorsal myelographic column reduction was significantly different between
 compressed site and non-compressed sites. Full myelographic area (FMA),
 dural area (DA), and spinal cord area (SCA) were significantly smaller in
 the CVCM horses, and were significantly smaller at compressed sites when
 compared to non-compressed sites. Reductions of FMA and DA and ratios of
 spinal cord area to full myelographic and dural area were significantly
 larger at compressed sites when compared to non-compressed sites.
 Diagnostic thresholds to consider for CVCM are FMA&lt;294mm2,
 DA&lt;188mm2, and SCA &lt;104mm2. Compressed sites were associated
 with thresholds of FMA&lt;274mm2, DA&lt;188mm2, or reduction of
 FMA&gt;9%, reduction of DA&gt;14%, SCA:FMA&gt;36.7%, and
 SCA:DA&gt;57.9%. Main limitations: Small number of horses. CVCM horses
 were younger than control horses. Conclusions: CBCT myelography provides
 quantitative parameters that can support a diagnosis of CVCM and should be
 used alongside radiographic myelography.
description: # Cone beam computed tomographic myelography in horses with cervical
 vertebral compressive myelography Dataset DOI:
 [10.5061/dryad.kprr4xhj9](https://doi.org/10.5061/dryad.kprr4xhj9) ##
 Description of the data and file structure Morphometric data from
 radiographs and myelogram cervical spine horse ### Files and variables
 #### Files: Ratios-YNL_Rater_assessment_copy.xlsx;
 Ratios-SGM_rater_assessment_copy.xlsx;
 Ratios-Barrett_rater_asessment_copy.xlsx **Description:** The 3 files are
 similar and show data from morphometric data on cervical spine images from
 3 investigators (one sheet for each investigator); 2 sheets show data from
 the first and second round of measurements; data is derived from plain
 radiographs, and from radiographic myelograms in neutral, extended, and
 flexed neck positions; n/a = data was not obtained due to no matching
 image **Variables** * Case - case number * Site - vertebral body * X-A -
 canal (mm) * X-B -  cranial body (mm) * X-C1 (mm) * RATIOS (A/B) * MIV-DC
 - intervertebral dural column (mm) * MIV-FC - intervertebral full
 column (mm) * MMV-DC - mid body dural column (mm) * MMV-FC - mid body full
 column (mm) * MIV-H - intervertebral - height (mm) * MMV-H - mid body -
 height (mm) * #### **File: CVM_project-_xrays_measurement_copy.xlsx**
 **Description:** Complete Morphometric data on cervical spine images;
 signalment and case information in sheet 1, measurements in sheet 2,
 sagittal ratios in sheet 3, DMC reductions in sheet 4, compressed site
 measurements in sheet 5, and CT measurements in sheet 6; n/a = data was
 not obtained due to no matching image ##### Variables * Sheet 1: Case
 information * Control Case numbers (ID) * Case Case numbers (ID) * Sites
 of compression (vertebral sites) * Ataxia grade (Mayhew scale 1-5) * Age
 (years) * Anesthesia duration (hours) * Gender (mare, stallion, gelding) *
 Number represented in table (1-10) * CT xcel (number on CT sheet 1-10) *
 Sheet 2: All measurements for each site each case * X-A - canal (mm) * X-B
 -  cranial body (mm) * X-C1 (mm) * MIV-DC - intervertebral dural column
 (mm) * MIV-FC - intervertebral full column (mm) * MMV-DC - mid body dural
 column (mm) * MMV-FC - mid body full column (mm) * MIV-H - intervertebral
 - height (mm) * MMV-H - mid body - height (mm) * Sheet 3: Sagittal ratio
 measurements for each site for each case (mm) * Sheet 4: Myelographic
 measurements for each site for each case and Sheet 5: Compressed sites *
 DD- dural diamater (mm) * DMC - dural myelographic column (mm) * SCH -
 spinal cord height (mm) * Sheet 6: CT measurements * IVC FMA -
 intervertebral full myelographic area (mm^2^) * IVC SCA - intervertebral
 spinal cord area (mm^2^) * MB FMA - mid body full myelographic
 area (mm^2^) * MB SCA - mid body spinal cord area (mm^2^) * IV DA -
 intervertebral dural area (mm^2^) * MB DA - mid body dural area (mm^2^)
 #### ## Code/software Microsoft Xcel