Vertebral Canal

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Timo Prange - One of the best experts on this subject based on the ideXlab platform.

  • epiduroscopy of the lumbosacral Vertebral Canal in the horse technique and endoscopic anatomy
    Equine Veterinary Journal, 2016
    Co-Authors: Timo Prange, B D Shrauner, Anthony T Blikslager
    Abstract:

    Summary Reasons for performing study Back pain is a common cause of gait alterations and poor performance in horses, but the available imaging modalities are frequently insufficient to isolate the underlying pathology. In human patients, epidural endoscopy (epiduroscopy) is successfully used to diagnose and treat challenging cases of lower back pain. Endoscopy of the cervical epidural space has previously been reported in anaesthetised horses. Objectives To develop a technique for lumbosacral epiduroscopy in standing horses and to describe the endoscopic anatomy of the lumbosacral epidural space. Study design Pilot study to assess the feasibility of lumbosacral epiduroscopy in 5 horse cadavers. Methods The cadavers of 5 horses, weighing 457–694 kg (mean, 570 kg), were suspended in an upright position. Vascular dilators of increasing size were inserted between the first 2 moveable vertebrae caudal to the sacrum to create a minimally invasive approach into the epidural space. A flexible videoendoscope was introduced and advanced as far cranially as the length of the endoscope permitted. The lumbosacral epidural space underwent gross necropsy examination following the procedure. Results The endoscope was successfully inserted into the epidural space in all horses. Saline injection through the working channel of the endoscope allowed the following anatomical structures to be seen: dura mater, left and right lumbosacral spinal nerves, cauda equina, epidural fat, connective tissue and blood vessels. Using the 60 cm working length of the endoscope, the epidural space could be examined as far cranial as L3–T18, depending on the size of the horse. No gross damage to epidural neurovascular structures was observed on necropsy examination. Conclusion Lumbosacral epiduroscopy is technically feasible in standing horses and may become a valuable diagnostic tool in horses with caudal back or limb pain of unknown origin. Studies in live horses will be necessary to evaluate the safety of the procedure.

  • cervical Vertebral Canal endoscopy in a horse with cervical Vertebral stenotic myelopathy
    Equine Veterinary Journal, 2012
    Co-Authors: Timo Prange, Fernando L Garciapereira, Elizabeth A Carr, J A Stick, Jon S Patterson, F J Derksen
    Abstract:

    A 3-year-old Thoroughbred gelding presented with a history of neurological signs, including incoordination in his hindlimbs, of about 7 months' duration. On initial examination, the horse exhibited ataxia and paresis in all limbs with more severe deficits in the hindlimbs. Cervical radiographs displayed severe osteoarthritis of the articular processes between C5 and C6. On subsequent cervical myelography the dorsal contrast column was reduced by 90% at the level of the interVertebral space between C5 and C6. Cervical Vertebral Canal endoscopy, including epidural (epiduroscopy) and subarachnoid endoscopy (myeloscopy), was performed under general anaesthesia. A substantial narrowing of the subarachnoid space at the level between C6 and C7 was seen during myeloscopy, while no compression was apparent between C5 and C6. Epiduroscopy showed no abnormalities. After completion of the procedure, the horse was subjected to euthanasia and the cervical spinal cord submitted for histopathological examination. Severe myelin and axon degeneration of the white matter was diagnosed at the level of the interVertebral space between C6 and C7, with Wallerian degeneration cranially and caudally, indicating chronic spinal cord compression at this site. Myeloscopy was successfully used to identify the site of spinal cord compression in a horse with cervical Vertebral stenotic myelopathy, while myelography results were misleading.

  • cervical Vertebral Canal endoscopy in the horse intra and post operative observations
    Equine Veterinary Journal, 2011
    Co-Authors: Timo Prange, John A. Stick, Frederik J. Derksen, Fernando L Garciapereira, Elizabeth A Carr
    Abstract:

    Summary Reasons for performing study: Despite modern medical diagnostic imaging, it is not possible to identify reliably the exact location of spinal cord compression in horses with cervical Vertebral stenotic myelopathy (CVSM). Vertebral Canal endoscopy has been successfully used in man and a technique for cervical Vertebral Canal endoscopy (CVCE) has been described in equine cadavers. Objective: To determine the feasibility and safety of CVCE in healthy mature horses. Methods: Six healthy mature horses were anaesthetised. A flexible videoendoscope was subsequently introduced via the atlanto-occipital space into the epidural space (epiduroscopy, Horses 1-3) or the subarachnoid space (myeloscopy, Horses 4-6) and advanced to the 8th cervical nerve. Neurological examinations were performed after surgery and lumbosacral cerebrospinal fluid (CSF) analysed in horses that had undergone myeloscopy. Results: All procedures were completed successfully and all horses recovered from anaesthesia. Anatomical structures in the epidural space (including the dura mater, nerve roots, fat and blood vessels) and subarachnoid space (including the spinal cord, blood vessels, arachnoid trabeculations, nerve roots and the external branch of the accessory nerve) were identified. During epiduroscopy, a significant increase in mean arterial pressure was recognised, when repeated injections of electrolyte solution into the epidural space were performed. In one horse of the myeloscopy group, subarachnoid haemorrhage and air occurred, resulting in transient post operative ataxia and muscle fasciculations. No complications during or after myeloscopy were observed in the other horses. CSFanalysisindicatedmildinflammationonDay7withvalues approaching normal 21 days after surgery. Conclusions: Endoscopic examination of the epidural and subarachnoid space from the atlanto-occipital space to the 8th cervical nerve is possible and can be safely performed in healthy horses. Potential relevance: Cervical Vertebral Canal endoscopy might allow accurate identification of the compression site in horses with CVSM and aid diagnosis of other lesions within the cervical Vertebral Canal.

  • Endoscopic anatomy of the cervical Vertebral Canal in the horse: a cadaver study.
    Equine Veterinary Journal, 2010
    Co-Authors: Timo Prange, John A. Stick, Frederik J. Derksen, Fernando L. Garcia-pereira
    Abstract:

    Summary Reason for performing study: Localisation of spinal cord compression in horses with cervical Vertebral stenotic myelopathy is inexact. Vertebral Canal endoscopy has been used in man to localise spinal cord lesions and has the potential to become a useful diagnostic technique in horses. Objective: To establish a surgical approach via the atlanto-occipital space to the cervical Vertebral Canal in equine cadavers and describe the endoscopic anatomy of the cervical epidural and subarachnoid spaces. Methods: The cadavers of 25 mature horses were used to assess 3 surgical methods to approach the cervical Vertebral Canal, including 2 minimally invasive and one open technique. Once the approach had been made, a flexible videoendoscope was inserted into the epidural space (epiduroscopy) or the subarachnoid space (myeloscopy) and advanced caudally until the interVertebral space between C7 and T1 was reached. Results: The epidural and subarachnoid spaces could not be accessed reliably using the minimally invasive techniques. Furthermore, damage to the nervous tissues was a frequent complication with these procedures. The open approach allowed successful insertion of the videoendoscope into the epidural and subarachnoid spaces in all horses and no inadvertent damage was observed. Anatomical structures that could be seen in the epidural space included the dura mater, nerve roots, fat and the ventral internal Vertebral venous plexus. In the subarachnoid space, the spinal cord, nerve roots, blood vessels, denticulate ligaments and external branch of the accessory nerve were seen. Conclusions: Using the open approach, epiduroscopy and myeloscopy over the entire length of the cervical Vertebral Canal are possible in the mature horse. Potential relevance: Cervical Vertebral Canal endoscopy may become a valuable tool to localise the site of spinal cord injury in horses with cervical Vertebral stenotic myelopathy and could aid in the diagnosis of other diseases of the cervical spinal cord.

Richard W Porter - One of the best experts on this subject based on the ideXlab platform.

  • antenatal factors in the development of the lumbar Vertebral Canal a magnetic resonance imaging study
    Spine, 2003
    Co-Authors: J E Jeffrey, Doris M Campbell, Michael H N Golden, Francis W Smith, Richard W Porter
    Abstract:

    Study Design. The lumbar Vertebral Canal was measured in two cohorts of 10-year-old children (n = 161) using magnetic resonance imaging (MRI) and compared with obstetric records. Objective. To investigate whether there are identifiable obstetric factors that determine the size of the lumbar Vertebral Canal. Summary of Background Data. The most rapid period growth for the lumbar Vertebral Canal is between 12 and 32 weeks in utero, with the midsagittal diameter of L1–L4 already 70% of adult dimension at birth. Therefore, adverse antenatal factors during this critical growth period may be expected to affect the size of the Canal. Methods. The Canal size was measured from axial MRI sections taken through each lumbar vertebra (L1–L5) at the pedicular level of 84 children. Relations with obstetric data, prospectively collected in a neonatal database, were sought. The relation of low birthweight and Canal size was further investigated in a second cohort of children (n = 77). Results. The Canal size, particularly the midsagittal diameter and the cross-sectional area, was found to be significantly reduced by low birthweight (with growth retardation in utero being a more important factor than length of gestation), low placenta weight, and lower socioeconomic class. Smoking during pregnancy significantly reduced the perimeter at L3 (P = 0.032) and L5 (P = 0.031), and also the cross-sectional area at L3 (P = 0.030) and L5 (P = 0.016). Conclusions. This study showed that, for this group of children, the size of the lumbar Vertebral Canal was reduced by low birthweight, with maternal smoking as an added adverse factor. Therefore, good antenatal care and maternal education may help to reduce the risk of spinal stenosis in adult life.

  • idiopathic scoliosis the relation between the Vertebral Canal and the Vertebral bodies
    Spine, 2000
    Co-Authors: Richard W Porter
    Abstract:

    Study design. The axial length of the Vertebral Canal and the anterior aspect of the vertebrae were measured in 36 skeletons, 15 with probable idiopathic scoliosis. Objectives. To compare the discrepancy in length of the Vertebral Canal and the anterior spinal column in skeletons having probable idiopathic scoliosis with the degree of deformity. Summary and Background Data. In idiopathic scoliosis, the Vertebral bodies rotate toward the convexity of the curve, whereas the Vertebral Canal tends to retain a midline position. The Vertebral Canal therefore will be relatively short. The degree of shortening has not been described previously, nor its relation with the degree of deformity. Methods. The axial length of the Vertebral Canal and the anterior aspect of the Vertebral bodies were measured in 36 skeletons: 8 with normal spines, 13 with kypnosis, and 15 with probable idiopathic scoliosis. The relative shortening in the scoliotic spines was correlated with the Cobb angle and the degree of rotation. Results. No significant difference in length was found between the Vertebral Canal and the Vertebral column in the normal spines. The kyphotic spines had Canals significantly longer than the Vertebral length (P < 0.025). All but one of the scoliotic spines had short Vertebral Canals (P < 0.01). The degree of discrepancy was related to the Cobb angle (r = -0.50; P < 0.05), and particularly to the degree of rotation (r = -0.88; P < 0.001). Conclusions. The findings have surgical and etiologic implications. The results are consistent with a conceivable hypothesis that in some patients with idiopathic scoliosis, there may be impaired growth in the length of the spinal cord, the posterior elements are tethered, and as the Vertebral bodies continue to grow, they become lordotic and then rotate.

  • development of the lumbar and sacral Vertebral Canal in utero
    Journal of Pediatric Orthopaedics, 1997
    Co-Authors: Traian R S Ursu, Richard W Porter, Visvan Navaratnam
    Abstract:

    Study design This study analyzed the development of the lumosacral Vertebral Canal and dural sac in human fetus. A collection of fetuses and embryos was used to assess the development of different parameters of the spinal Canal. Objectives The data were analyzed for the dynamics of the development and also compared with mean adult spinal parameters. Summary of background data Transversely sectioned specimens and nonsectioned specimens free of abnormalities were selected from the Boyd Collection of human embryos and fetuses. Methods The sections were photographed alongside a micrometric scale, and the nonsectioned specimens were scanned by magnetic resonance imaging. The films were computer analyzed for spinal and dural parameters. The error of the measurements was assessed. Results The most rapid growth period of the spinal Canal parameters is between 18-36 weeks' gestation. After 30 weeks of intrauterine life, the upper lumbar Canal grows faster than the lower lumbar region. The distal end of the dural sac begins to rise from S5 after 14 weeks. Conclusions At the end of intrauterine growth, the interpedicular diameter of the spinal Canal from L1 to L4 is 70% of the adult size, however, at L5, the Canal is only 50% mature at birth. Therefore, if there is growth impairment in early infancy, the upper lumbar region is partially protected in contrast with the L5 level.

  • the growth of the lumbar Vertebral Canal
    Spine, 1994
    Co-Authors: Tibor Papp, Richard W Porter, R M Aspden
    Abstract:

    Study Design This study examines the growth and development of the lumbar spinal Canal with emphasis on early life. Objective Changes in dimensions of the Canal were investigated throughout life. Summary of Background Data Seven hundred and fifteen lumbar vertebrae were examined from the Spitalfield Collection of Skeletons at the Natural History Museum, London. Methods Ummagnified silhouette pictures were taken of the Canals with a specially designed photographic box. Computerized image analysis provided the accurate measurements. Results Regarding the midsagittal diameter and the cross-sectional area, the cranial four lumbar vertebrae were already fully matured in infants. At L5 there was significant increase up to 4 years of age when the midsagittal diameter was even larger than in the adult. The interpedicular diameter significantly increased at L1 until 10 years of age, at the other levels until adulthood, as did the perimeter at L4 and L5 until 14 years of age. The shape of the Canal was assessed by measuring the circularity, the 'trefoilness' and the situation of the centroid. The first measurement significantly decreased with age, the trefoilness increased until adulthood, and the centroid of the Canal approached the Vertebral body. In spines with spina bifida occulta, the lumbar Canal was significantly larger proximal to the lesion than in the unaffected spines. Conclusion The lumbar spinal Canal exhausts its growth potential by infancy as regards the midsagittal diameter and the cross-sectional area. Thus, in the case of delayed development, it is not capable of catch-up growth.

Steven De Decker - One of the best experts on this subject based on the ideXlab platform.

  • thoracic Vertebral Canal stenosis associated with Vertebral arch anomalies in small brachycephalic screw tail dog breeds
    Veterinary and Comparative Orthopaedics and Traumatology, 2021
    Co-Authors: Alessandro Conte, Steven De Decker, Marco Bernardini, Cristoforo Ricco, Sebastien Behr, Daniel Sanchezmasian, Guinio B Cherubini, Luisa De Risio, Rodrigo Gutierrezquintana
    Abstract:

    Objective The aim of this study was to describe clinical and imaging features of thoracic Vertebral Canal stenosis secondary to the hypertrophy of the Vertebral lamina and articular processes in screw-tail brachycephalic dog breeds, to evaluate the prevalence of the malformation in a large group of screw-tail dog breeds and to determine if degree of stenosis is associated with presence of neurological signs. Study Design This is a retrospective multicentric study. Materials and Methods Clinical records of 185 screw-tail brachycephalic dogs (French Bulldogs, English Bulldogs, Boston Terriers) and Pugs were reviewed. Ten dogs with neurological deficits secondary to thoracic Vertebral Canal stenosis diagnosed on magnetic resonance imaging were identified (Group 1). Neurologically normal dogs (n = 175) of the same breeds underwent computed tomographic imaging of the thoracic Vertebral column for other medical reasons (Group 2). Cross-sectional measurements were used to calculate a stenotic ratio. Results Group 1 consisted of three French Bulldogs, six English Bulldogs and one Pug. Eight were males. Most dogs presented with progressive non-painful pelvic limbs ataxia and paresis. Twenty stenotic sites were identified with the most common being T4–T5. Three of ten dogs were treated surgically and all had a good long-term outcome. In Group 2, 33 of 175 dogs had one or more stenotic sites with the most common being T2–T3. The degree of the stenosis was significantly higher in Group 1 (p = 0.019). A stenotic ratio of 0.56 had sensitivity and specificity of 67% to differentiate between dogs with and without neurological signs. Conclusion Cranial thoracic Vertebral Canal stenosis is observed predominantly in young male Bulldogs, but not all stenoses are clinically relevant.

  • thoracic Vertebral Canal stenosis in cats clinical features diagnostic imaging findings treatment and outcome
    Journal of Feline Medicine and Surgery, 2020
    Co-Authors: Sabrina Gillespie, Steven De Decker
    Abstract:

    ObjectivesThe aim of this study was to describe the clinical features, diagnostic imaging findings, treatment and outcome in cats with thoracic Vertebral Canal stenosis (TVCS).MethodsMedical record...

  • lumbosacral transitional vertebrae in cats and its relationship to lumbosacral Vertebral Canal stenosis
    Journal of Feline Medicine and Surgery, 2019
    Co-Authors: Georgina Harris, Jessica Ball, Steven De Decker
    Abstract:

    ObjectivesAlthough a clear relationship has been demonstrated between the presence of lumbosacral transitional vertebrae and the development of lumbosacral stenosis in dogs, this relationship has n...

  • Radiographic Vertebral Canal and Vertebral body ratios in Doberman Pinschers with and without clinical signs of caudal cervical spondylomyelopathy.
    American journal of veterinary research, 2011
    Co-Authors: Steven De Decker, Jimmy Saunders, Luc Duchateau, Pascaline Pey, Luc Van Ham
    Abstract:

    Objective—To determine radiographic Vertebral ratio values representing Vertebral Canal stenosis in Doberman Pinschers with and without clinical signs of caudal cervical spondylomyelopathy (CCSM). Animals—Doberman Pinschers with (n = 81) and without (39) signs of CCSM. Procedures—All dogs underwent lateral survey radiography of the cervical Vertebral column. Five specific measurements were made at C3 through C7, and from those data, 3 ratios were calculated and analyzed for use in diagnosis of CSSM: Canal height-to-Vertebral body height ratio (CBHR), Canal height-to-Vertebral body length ratio (CBLR), and caudal Vertebral Canal height-to-cranial Vertebral Canal height ratio (CCHR). The CBHR and CBLR were considered indicators of Vertebral Canal stenosis, and CCHR described Vertebral Canal shape. Results—Compared with Doberman Pinschers without CCSM, mean CBHR and CBLR values were significantly smaller for Doberman Pinschers with CCSM; for CBHR, this difference was evident at each assessed vertebra. The CC...

  • Magnetic resonance imaging Vertebral Canal and body ratios in Doberman Pinschers with and without disk-associated cervical spondylomyelopathy and clinically normal English Foxhounds
    American journal of veterinary research, 2011
    Co-Authors: Steven De Decker, Jimmy Saunders, Luc Duchateau, Ingrid Gielen, Henri Van Bree, Ingeborgh Polis, Luc Van Ham
    Abstract:

    Objective—To determine magnetic resonance imaging (MRI) Vertebral ratio values representing Vertebral Canal height, Vertebral Canal shape, and Vertebral body shape in Doberman Pinschers with and without disk-associated cervical spondylomyelopathy (DACSM) and clinically normal English Foxhounds. Animals—Doberman Pinschers with (n = 18) and without (20) DACSM and clinically normal English Foxhounds (18). Procedures—All dogs underwent low-field MRI of the cervical Vertebral column. From 5 specific measurements made at C3 through C7, 4 linear Vertebral ratios were calculated and assessed for correlation: Vertebral Canal height-to-body height ratio (CBHR), Vertebral Canal height-to-body length ratio (CBLR), caudal Canal height-to-cranial Canal height ratio (CCHR), and Vertebral body length-to-height ratio (BLHR). The CBHR and CBLR described Vertebral Canal height, CCHR described Vertebral Canal shape, and BLHR described Vertebral body shape. A midVertebral Canal-occupying ratio (mVCOR) for the spinal cord was ...

Elizabeth A Carr - One of the best experts on this subject based on the ideXlab platform.

  • cervical Vertebral Canal endoscopy in a horse with cervical Vertebral stenotic myelopathy
    Equine Veterinary Journal, 2012
    Co-Authors: Timo Prange, Fernando L Garciapereira, Elizabeth A Carr, J A Stick, Jon S Patterson, F J Derksen
    Abstract:

    A 3-year-old Thoroughbred gelding presented with a history of neurological signs, including incoordination in his hindlimbs, of about 7 months' duration. On initial examination, the horse exhibited ataxia and paresis in all limbs with more severe deficits in the hindlimbs. Cervical radiographs displayed severe osteoarthritis of the articular processes between C5 and C6. On subsequent cervical myelography the dorsal contrast column was reduced by 90% at the level of the interVertebral space between C5 and C6. Cervical Vertebral Canal endoscopy, including epidural (epiduroscopy) and subarachnoid endoscopy (myeloscopy), was performed under general anaesthesia. A substantial narrowing of the subarachnoid space at the level between C6 and C7 was seen during myeloscopy, while no compression was apparent between C5 and C6. Epiduroscopy showed no abnormalities. After completion of the procedure, the horse was subjected to euthanasia and the cervical spinal cord submitted for histopathological examination. Severe myelin and axon degeneration of the white matter was diagnosed at the level of the interVertebral space between C6 and C7, with Wallerian degeneration cranially and caudally, indicating chronic spinal cord compression at this site. Myeloscopy was successfully used to identify the site of spinal cord compression in a horse with cervical Vertebral stenotic myelopathy, while myelography results were misleading.

  • cervical Vertebral Canal endoscopy in the horse intra and post operative observations
    Equine Veterinary Journal, 2011
    Co-Authors: Timo Prange, John A. Stick, Frederik J. Derksen, Fernando L Garciapereira, Elizabeth A Carr
    Abstract:

    Summary Reasons for performing study: Despite modern medical diagnostic imaging, it is not possible to identify reliably the exact location of spinal cord compression in horses with cervical Vertebral stenotic myelopathy (CVSM). Vertebral Canal endoscopy has been successfully used in man and a technique for cervical Vertebral Canal endoscopy (CVCE) has been described in equine cadavers. Objective: To determine the feasibility and safety of CVCE in healthy mature horses. Methods: Six healthy mature horses were anaesthetised. A flexible videoendoscope was subsequently introduced via the atlanto-occipital space into the epidural space (epiduroscopy, Horses 1-3) or the subarachnoid space (myeloscopy, Horses 4-6) and advanced to the 8th cervical nerve. Neurological examinations were performed after surgery and lumbosacral cerebrospinal fluid (CSF) analysed in horses that had undergone myeloscopy. Results: All procedures were completed successfully and all horses recovered from anaesthesia. Anatomical structures in the epidural space (including the dura mater, nerve roots, fat and blood vessels) and subarachnoid space (including the spinal cord, blood vessels, arachnoid trabeculations, nerve roots and the external branch of the accessory nerve) were identified. During epiduroscopy, a significant increase in mean arterial pressure was recognised, when repeated injections of electrolyte solution into the epidural space were performed. In one horse of the myeloscopy group, subarachnoid haemorrhage and air occurred, resulting in transient post operative ataxia and muscle fasciculations. No complications during or after myeloscopy were observed in the other horses. CSFanalysisindicatedmildinflammationonDay7withvalues approaching normal 21 days after surgery. Conclusions: Endoscopic examination of the epidural and subarachnoid space from the atlanto-occipital space to the 8th cervical nerve is possible and can be safely performed in healthy horses. Potential relevance: Cervical Vertebral Canal endoscopy might allow accurate identification of the compression site in horses with CVSM and aid diagnosis of other lesions within the cervical Vertebral Canal.

James N Macleod - One of the best experts on this subject based on the ideXlab platform.

  • comparison of magnetic resonance imaging with standing cervical radiographs for evaluation of Vertebral Canal stenosis in equine cervical stenotic myelopathy
    Equine Veterinary Journal, 2014
    Co-Authors: J G Janes, S M Reed, K S Garrett, K J Mcquerry, Anthony Pease, Neil M Williams, James N Macleod
    Abstract:

    Summary Reasons for performing study The sensitivity and specificity of lateral cervical radiographs to evaluate horses suspected of cervical stenotic myelopathy (CSM) are limited by the assessment being restricted to the sagittal plane. Objective To determine whether magnetic resonance imaging (MRI) allows for a more accurate identification of stenosis than lateral cervical radiographs in horses with CSM. Study design Case control study. Methods Nineteen Thoroughbred horses with CSM (17 males, 2 females, age 6–50 months) were compared to 9 control Thoroughbreds (6 males, 3 females, age 9–67 months). Ante mortem, the subjects had neurological examinations and standing cervical radiographs with sagittal ratios calculated from C3 to C7. Intact cervical column MRI scans and histological examinations of the spinal cord were performed post mortem. Morphometric parameters were measured on the Vertebral Canal, spinal cord and interVertebral foramen. Results Radiographic cervical Canal height measurements categorised by standard minimal sagittal diameter intraVertebral and interVertebral ratios produced several false positive and false negative determinations of Canal stenosis as defined by spinal cord histopathology. Post mortem MRI measurements of Canal area and cord Canal area ratio more accurately predicted sites of cord compression in CSM cases. No differences in spinal cord measurements were observed when comparing CSM to control horses, but each of the Vertebral Canal parameters achieved significance at multiple sites. Conclusions Vertebral Canal area and cord Canal area ratio are better parameters to predict the location of cervical Canal stenosis compared to only the sagittal plane of Canal height. Additional visual planes and measurements obtained by MRI, specifically Vertebral Canal area and the cord Canal area ratio, will provide a more accurate method to identify regions of Canal stenosis than lateral cervical radiographs. The development of MRI or computed tomography equipment capable of evaluating the cervical column of mature horses may substantially enhance evaluation of CSM patients. The Summary is available in Chinese – see Supporting information.