Myelo-CT imaging findings in 15 dogs with surgically-treated cervical acute compressive hydrated nucleus pulposus extrusion.

Compressive hydrated nucleus pulposus extrusion (HNPE) is a sudden extrusion of hydrated, nondegenerated nucleus pulposus material with well-known characteristic MRI findings. The appearance of compressive HNPE during contrast-enhanced CT has already been described, but never its myelo-CT characteristics. The aim of this retrospective multicenter case series is to describe the myelo-CT findings in 15 dogs with compressive HNPE confirmed with gross surgical findings. A distinctive and consistent myelo-CT appearance of cervical compressive HNPE in dogs that included a focal extradural "seagull"-shaped extradural compression dorsal to the annulus fibrosus combined with a narrowing of the affected intervertebral disc space was found. The extruded material was hypoattenuating in the soft tissue algorithm. Myelo-CT could be a useful diagnostic tool and influence the clinical decision to address cervical compressive HNPE conservatively or surgically when MRI is not available.

IV Versus Myelography Computed Tomography for Thoracolumbar Intervertebral Disc Extrusion Surgical Planning in French Bulldogs.

Accurate diagnostic imaging is required for surgical planning of acute thoracolumbar intervertebral disc extrusion. However, data comparing the accuracy of conventional IV contrast-injected computed tomography (CT) and myelography CT for hemilaminectomy localization and size assessment are sparse. In this study, IV contrast-injected CT and myelography CT were performed in 48 French bulldogs presenting with acute disc herniation and compared with postsurgical CT. CT images were evaluated by three raters. IV contrast-injected CT erroneously identified the compressive lesion site significantly more often than myelography CT. The length of the compressive lesion was significantly higher using myelography CT compared with conventional CT, but this did not lead to relevant consequences on the surgical opening site length. Myelography CT should therefore be recommended when thoracolumbar disc disease is suspected and multiple compressive lesions are visualized on IV-injected CT in French bulldogs.

CT myelographic diagnosis of ligamentum flavum hypertrophy in a Warmblood Gelding with progressive ataxia.

An 8-year-old Warmblood gelding presented with a history of progressive ataxia for 6 weeks. Intra- and intervertebral ratios measured from lateral radiographs of the cervical spine were within normal limits. Computed tomographic myelography of the cervical spine revealed focal compression of the dorsal and the ventral contrast column as well as a ventral displacement of the spinal cord within the spinal canal due to a bulging of soft tissue attenuating material in the dorsal half of the intervertebral junction of C6 and C7. Post-mortem histopathological examination confirmed chondroid metaplasia of the ligamentum flavum at C6-C7.

Concurrent spinal epidural empyema and endocarditis in a dog.

A 9-year-old neutered male Rhodesian ridgeback cross dog was evaluated for progressive non-ambulatory paraparesis, fever, and leukocytosis. The dog was diagnosed with spinal epidural empyema (SEE) and infectious endocarditis (IE) of the mitral valve based on the findings of contrast-enhanced computed tomography (CT), CT myelography, echocardiography, and bacterial culture. The report herein describes the clinical presentation, CT findings, clinical and surgical management of this case, together with the electrocardiography, and echocardiography findings. To the authors' knowledge, this is the first reported case of spinal epidural empyema likely to be caused by infectious endocarditis of the mitral valve in a dog.

Empyème épidural spinal concomitant à une endocardite chez un chien. Un chien mâle castré croisé Rhodesian Ridgeback âgé de 9 ans a été évalué pour une paraparésie progressive non-ambulatoire, de la fièvre et une leucocytose. Un diagnostic d'empyème épidural spinal (SEE) et d'endocardite infectieuse (IE) de la valvule mitrale a été émis basé sur les trouvailles de la tomodensitométrie (CT), d'une myélographie CT, de l'échocardiographie, et de la culture bactérienne. Le présent rapport décrit la présentation clinique, les trouvailles de CT, la gestion clinique et chirurgicale de ce cas, de même que les trouvailles par électrocardiographie et échocardiographie. À la connaissance des auteurs, ceci représente le premier cas rapporté d'empyème épidural spinal à être causé par une endocardite infectieuse de la valvule mitrale chez un chien.(Traduit par Dr Serge Messier).

Current dorsal myelographic column and dural diameter reduction rules do not apply at the cervicothoracic junction in horses.

Previously published myelographic studies do not report findings at the junction between the seventh cervical (C7) and first thoracic vertebrae (T1). Modern digital radiographic equipment allows improved visualization of C7-T1. Based on clinical experience, we hypothesized that 50% reduction of the dorsal myelographic column or 20% reduction of the dural diameter, criteria commonly used as a supportive finding for spinal cord compression in the cervical vertebral column, do not apply at C7-T1. A myelographic study was performed on 12 healthy, neurologically normal horses. Our hypothesis was confirmed; using established criteria eight of 12 horses would have been classified as having evidence of spinal cord compression at C7-T1. The dorsal myelographic column reduction at C7-T1 was 48 ± 12%, while the C6-C7 dorsal myelographic column reduction was 33 ± 17% (mean ± standard deviation) (P = 0.010). The dural diameter reduction at C7-T1 (22.0 ± 6.7%) was significantly greater than the dural diameter reduction at C6-C7 (13.2 ± 9.5%) (P = 0.0007). Further measurements and comparisons suggested that the apparent greater reduction of dorsal myelographic column and dural diameter at C7-T1 was due to larger intravertebral measurements at C7 rather than smaller intervertebral values at C7-T1. Based on these findings, alternative criteria should be used at C7-T1 when assessing clinical cases for cervical stenotic myelopathy. Reduction of the dorsal myelographic column by 60% or of the dural diameter by 30% would avoid high numbers of false positive myelographic cases at C7-T1.

Investigation of parameters predicting the need for diagnostic imaging beyond computed tomography in the evaluation of dogs with thoracolumbar myelopathy: Retrospective evaluation of 555 dogs.

Thoracolumbar myelopathy encompasses a number of disease processes such as intervertebral disc disease, discospondylitis, trauma, congenital malformations, neoplasia, and intramedullary spinal cord disease. Compressive disc herniations are most common in dogs and require imaging procedures such as myelography, computed tomography (CT), and/or magnetic resonance imaging (MRI) to determine the need and location for decompressive surgery. The purposes of this retrospective, cross-sectional study were to evaluate all dogs undergoing thoracolumbar CT imaging as the initial diagnostic step between 2010 and 2015 and determine whether any of the imaging characteristics could be used to predict the need for additional imaging in the form of myelography, CT myelography, and/or MRI. A total of 555 dogs were identified in this time frame which underwent CT imaging for myelopathy of the thoracolumbar region. Various parameters including age, gender, sexual status, breed, chronicity, site of lesion, time of study, and contrast administration were evaluated. Findings indicated that 7.6% of dogs needed additional imaging after CT. Dachshunds were less likely to need additional imaging (P = 0.0111) as were patients scanned during normal business hours (P = 0.0075). Increasing age of the patient increased the likelihood of additional imaging (P = 0.0107). Dogs which did not have additional imaging performed were 21.89 times more likely to require surgery than those which did have additional imaging (P < 0.0001). Findings supported the use of CT as a first-line imaging modality for dogs presenting with thoracolumbar myelopathy.

High-Definition Video Telescope-Assisted Ventral Slot Decompression Surgery for Cervical Intervertebral Disc Herniation in 30 Dogs.

OBJECTIVE: To describe the use of a video telescope operating monitor (VITOM™) for ventral slot decompression and to report its clinical applications using preoperative and postoperative computed tomography (CT) myelography. STUDY DESIGN: Prospective case series. ANIMALS: Consecutive dogs presented with cervical intervertebral disc disease requiring surgical decompression (n = 30). METHODS: Demographic data, preoperative neurological status, localization and lateralization of the compression, total operative time, surgical complications, ventral slot size and orientation, hospitalization time, and postoperative outcome were recorded. Preoperative and postoperative spinal cord area at the compression site and ratios of compressed to normal spinal cord area were calculated by CT myelography. RESULTS: French Bulldogs were the most common breed of dogs (n = 15; 50%) and neck pain was the most common neurological sign (n = 18; 60%). Postoperative CT myelography confirmed that spinal cord decompression, postoperative spinal cord area, and the ratios of compressed to normal spinal cord area improved significantly compared with preoperative measurements (P = .01). Sinus bleeding occurred in 20% of dogs. The mean ratios (± SD) of ventral slot length and width compared with vertebral body length and width were 0.21 ± 0.08 and 0.31 ± 0.07, respectively. The mean postoperative hospitalization time was 3.0 ± 0.6 days and all dogs showed clinical improvement and an excellent outcome. CONCLUSION: The VITOM™ ventral slot decompression technique was fast and easy to perform. It allowed a minimally invasive approach with a small ventral slot while improving spinal cord visualization. The results of this study support the use of the VITOM™ technique in spinal veterinary surgery.

Dispersal pattern of injectate following CT-guided perineural infiltration in the canine thoracolumbar spine: a cadaver study.

An increasing proportion of canine patients are presented with chronic thoracolumbar back pain and without compressive spinal lesions. In humans, spinal perineural infiltrations have been reported to have a favorable effect on pain control. The purpose of this prospective cadaver study was to describe the dispersal pattern of injectate following CT-guided spinal perineural infiltration in the canine thoracolumbar region. Seven fresh canine cadavers were first scanned using multislice CT and then CT-guided spinal perineural infiltration was performed at 42 sites from T13/L1 to L6/L7. The injectate for each site was a mixture of new methylene blue and iodinated contrast medium. Immediately following CT-guided injection, cadavers were frozen, cut, and dissected macro- and mesoscopically (using a magnifying glass) to identify anatomic structures that were infiltrated. In the majority of sites (64.3%), complete epidural and hypaxial staining of spinal nerve components (including the spinal ganglion, trunk, and ventral branch) was successfully achieved. However, no (11.9%) or unpredictable staining (9.5%) of nervous tissue occurred in some sites despite careful CT guidance and the application of relatively large volumes of injectate. Optimal results were achieved when the needle tip was positioned periforaminally ventral to the cranial contour of the cranial articular process. Findings from this ex vivo study indicated that CT-guided spinal perineural infiltration is feasible for testing in the canine thoracolumbar region and that successful nerve tissue infiltration would likely occur in the majority of sites. Future in vivo studies are needed to determine the safety and efficacy of this technique.

Thoracolumbar intradural disc herniation in eight dogs: clinical, low-field magnetic resonance imaging, and computed tomographic myelography findings.

Intradural disc herniation is a rarely reported cause of neurologic deficits in dogs and few published studies have described comparative imaging characteristics. The purpose of this retrospective cross sectional study was to describe clinical and imaging findings in a group of dogs with confirmed thoracolumbar intradural disc herniation. Included dogs were referred to one of four clinics, had acute mono/paraparesis or paraplegia, had low field magnetic resonance imaging (MRI) and/or computed tomographic myelography, and were diagnosed with thoracolumbar intradural disc herniation during surgery. Eight dogs met inclusion criteria. The prevalence of thoracolumbar intradural disc herniation amongst the total population of dogs that developed a thoracolumbar intervertebral disc herniation and that were treated with a surgical procedure was 0.5%. Five dogs were examined using low-field MRI. Lesions that were suspected to be intervertebral disc herniations were observed; however, there were no specific findings indicating that the nucleus pulposus had penetrated into the subarachnoid space or into the spinal cord parenchyma. Thus, the dogs were misdiagnosed as having a conventional intervertebral disc herniation. An intradural extramedullary disc herniation (three cases) or intramedullary disc herniation (two cases) was confirmed during surgery. By using computed tomographic myelography (CTM) for the remaining three dogs, an intradural extramedullary mass surrounded by an accumulation of contrast medium was observed and confirmed during surgery. Findings from this small sample of eight dogs indicated that CTM may be more sensitive for diagnosing canine thoracolumbar intradural disc herniation than low-field MRI.

Imaging diagnosis--Spinal epidural hemangiosarcoma in a dog.

An 8-year-old, male Boxer was examined for an acute onset of ambulatory paraparesis. Neurologic examination was consistent with a T3-L3 myelopathy. Myelography revealed an extradural spinal cord compression in the region of the T10-T13 vertebrae. On magnetic resonance (MR) imaging, a well-defined epidural mass lesion was detected. The mass was mildly hyperintense on T1-weighted, hyperintense on T2-weighted and STIR images compared to normal spinal cord and enhanced strongly and homogenously. Postmortem examination confirmed a primary epidural hemangiosarcoma. Findings indicated that the MRI characteristics of spinal epidural hemangiosarcoma may mimic other lesions including meningioma and epidural hemorrhages/hematomas of non-neoplastic etiology.

Atlanto-axial approach for cervical myelography in a Thoroughbred horse with complete fusion of the atlanto-occipital bones.

A 2-year-old Thoroughbred gelding with clinical signs localized to the first 6 spinal cord segments (C1 to C6) had complete fusion of the atlanto-occipital bones which precluded performing a routine myelogram. An ultrasound-assisted myelogram at the intervertebral space between the atlas and axis was successfully done and identified a marked extradural compressive myelopathy at the level of the atlas and axis, and axis and third cervical vertebrae.

Approche atlanto-axiale pour une myélographie cervicale chez un cheval Thoroughbred avec la fusion complète des os occipito-atloïdiens. Un hongre Thoroughbred âgé de 2 ans avec des signes cliniques localisés aux 6 premiers segments de la colonne vertébrale (C1 à C6) avait une fusion complète des os occipito-atloïdiens qui empêchait la réalisation d'un myélogramme de routine. Un myélogramme par échographie à l'espace intervertébral entre l'atlas et l'axis a été réalisé avec succès et a identifié une myélopathie extradurale compressive prononcée au niveau de l'atlas et de l'axis ainsi que de l'axis et de la troisième vertèbre cervicale.(Traduit par Isabelle Vallières).

Subarachnoid pressures and cardiorespiratory parameters during cisternal myelography in isoflurane anaesthetized dogs.

OBJECTIVE: To measure subarachnoid pressures, systemic circulatory and respiratory effects, and to calculate cerebral perfusion pressure during cisternal myelography. STUDY DESIGN: Prospective clinical study. ANIMALS: Forty-three client owned dogs with clinical signs of spinal disease, weighing 6-56 kg. METHODS: Dogs were premedicated with butorphanol and diazepam intravenously (IV) and anaesthesia was induced with propofol and maintained with isoflurane vaporized in oxygen. Ventilation was spontaneous. Heart and respiratory rates, invasive mean arterial blood pressure (MAP), end tidal carbon dioxide and isoflurane concentration were measured continuously. Initial subarachnoid pressure (SaP0 ) was measured in the cisterna magna with a needle pressure gauge. Iohexol 0.3 mL kg(-1) was injected at a rate of 4.1 mL minute(-1) into the cerebellomedullary cistern. The SaP was recorded during and at 120 seconds after contrast administration. The maximum SaP (SaPmax ) and minimum calculated cerebral perfusion pressure (CPPmin ) were recorded for each case. RESULTS: Prior to contrast injection, mean ± SD, MAP was 73 ± 20 mmHg and SaP0 was 10 ± 3 mmHg. The cerebral perfusion pressure (CPP) was 64 ± 20 mmHg. The contrast injection increased the SaP0 to 73 ± 33 mmHg (SaPmax ). After injection, MAP increased to 97 ± 25 mmHg and the CPP decreased to 14 ± 34 mmHg. A negative correlation was found between the lowest CPP and body weight (ρ = -0.77, p < 0.0001). Nine dogs had bradycardia, apnoea and hypertension, 21 dogs had at least one of these signs. The number of clinical signs showed significant correlation with body weight (ρ = -0.68, p < 0.0001), SaPmax (ρ = -0.66, p < 0.0001) and CPPmin (ρ = -0.73, p < 0.0001). CONCLUSIONS AND CLINICAL RELEVANCE: Cerebral perfusion can severely decrease during cisternal myelography using the standard dose of iohexol. Bradycardia, apnoea and systemic hypertension were associated with decreased CPP.

Dural tear and myelomalacia caused by an airgun pellet in a cat.

An 8-year-old cat was presented with severe neurological deficits secondary to a traumatic cervical spinal cord injury caused by an airgun pellet. This report describes, for the first time, the myelographic findings of a dural rupture in a cat and also describes a bilateral Horner's syndrome in a cat.

Déchirure durale et myélomalacie causées par le plomb d'un pistolet pneumatique chez un chat. Un chat âgé de 8 ans a été présenté avec des déficits neurologiques graves secondaires à une blessure traumatique de la moelle épinière cervicale causée par le plomb d'un pistolet pneumatique. Ce rapport décrit, pour la première fois, les résultats myélographiques d'une rupture durale chez un chat et aussi un syndrome de Horner chez un chat.(Traduit par Isabelle Vallières).

Distraction-stabilisation of two adjacent intervertebral spaces in a Dalmatian dog with caudal cervical spondylomyelopathy.

A 4-year-old, 40-kg, male, entire Dalmatian was presented for evaluation of chronic neck pain and pelvic limb ataxia. Myelography revealed ventrodorsal (hourglass) extradural compression over the intervertebral space between the 5th and 6th cervical vertebra and ventral extradural compression between the 6th and 7th cervical vertebra. Cranial compression disappeared and caudal compression markedly diminished after performing cervical traction. MRI scan confirmed protrusion of intervertebral discs and spinal cord compression in previously mentioned intervertebral spaces. Surgical distraction-stabilization of both intervertebral spaces was performed using threaded pins and polymethylmethacrylate. The convalescence from surgery was uneventful and the dog was walking without any signs of paresis until 5 months after surgery when radiography revealed implants loosening. The dog recovered fully of the implant removal and remained asymptomatic for more than 30 months.

The volume of extruded materials is correlated with neurologic severity in small-breed dogs with type I thoracolumbar intervertebral disk herniation.

OBJECTIVE: To assess whether the volume of extruded materials is correlated with neurologic severity in dogs with type I thoracolumbar intervertebral disk herniation (TL-IVDH). ANIMALS: 70 client-owned small-breed dogs with type I TL-IVDH diagnosed between July 1, 2016, and June 30, 2018. PROCEDURES: For this retrospective cohort study, the medical records of 70 dogs with surgically confirmed type I TL-IVDH were reviewed. The volume and height of the intervertebral disk and the area of the maximal transverse compressed spinal cord were measured using CT myelographic images. For each dog, the volume of the disk immediately cranial to the herniated disk was an internal control. Dogs were grouped on the basis of grade of neurologic severity. RESULTS: Preoperative grades of neurologic severity were grade 2 in 7 (10%) dogs, grade 3 in 16 (23%) dogs, grade 4 in 28 (40%) dogs, and grade 5 in 19 (27%) dogs. The total volume of the affected intervertebral disks was significantly larger than the internal control. Weak positive correlation was found between the volume of the extruded materials into the vertebral canal and the grade of neurologic severity. CLINICAL RELEVANCE: Our findings indicated that the total volume of the affected intervertebral disks is larger in dogs with type I TL-IVDH, and the volume of the extruded materials into the vertebral canal is weakly correlated with the neurologic severity.

Comparison of computed tomography and myelography to a reference standard of computed tomographic myelography for evaluation of dogs with intervertebral disc disease.

OBJECTIVE: To compare the sensitivity of computed tomography (CT) and myelography to a reference standard of CT myelography for determining localization of Type I intervertebral disc extrusions in dogs. STUDY DESIGN: Prospective blinded comparative study. ANIMALS: Dogs with acute onset myelopathy because of suspected disc extrusions (n = 30). METHODS: Dogs had CT, myelography, and CT myelography to diagnose disc extrusions. Sensitivity of CT and myelography was compared to CT myelography for lateral, longitudinal, and combined localization. Confidence in the assessment of each imaging study was scored by 3 reviewers. RESULTS: Sensitivity of CT for lateral, longitudinal, and combined localization was 94%, 91%, and 81%, respectively, and was 64%, 74%, and 53%, respectively for myelography. Sensitivity of all 3 categories of localization was significantly different between modalities (P < .0001, P = .0031, P < .0001). Significant differences in the sensitivity of lateral and combined localization were found between confidence scores for myelography (P < .0001, P < .0001). Significant differences in the sensitivity of lateral, longitudinal, and combined localization were found between confidence scores for CT (P = .011, P = .013, P = .027). Poor sensitivity was obtained for both modalities except when imaging studies were assigned the highest confidence score. CONCLUSIONS: CT is a more sensitive imaging technique than myelography for localizing disc extrusions when compared to a reference standard of CT myelography. Both modalities yielded high sensitivity with the highest confidence score and poor sensitivity for all other confidence scores.

Computed tomography myelography technique and spinal morphometry in healthy Yucatan pigs.

Porcine models of spinal cord injury (SCI) have an irreplaceable role in the development of experimental therapies. There is little literature regarding CT myelogram (CTM) techniques in swine and morphometry in miniature swine has not been established. A CT-guided method for performing myelography as well as reference values for spinal morphometry in healthy Yucatan miniature swine is lacking. The goal of this study is to describe a CT-guided method of performing CTM in a porcine model of SCI and to establish spinal morphometric reference values in mature Yucatan pigs. Six healthy, Yucatan sows, 9 months of age, weighing between 39-57.7kg, with no history of spinal disease, spinal injury, or neurologic deficits on physical exam were used in this study. CT myelography was performed in each sow under general anesthesia. CT scout images were used to guide needle placement at the L3-L4 intervertebral site. Once correct needle placement was confirmed using a 1ml test injection, a full dose of iodinated contrast (0.3ml/kg) was injected slowly over a 2-minute time period. Morphometry was performed using area measurements of the spinal cord (SC), vertebral body (VB), dural sac (DS), and vertebral canal (VC) at the mid-body and the intervertebral disc space of each spinal segment. Of the quantitative measurements, the spinal cord surface area had the widest range of values and the greatest coefficient of variance (CV) while those parameters for the vertebral canal had a low CV. Of the morphometric ratios, the DS:VC, had the lowest CV while the spinal cord ratios to DS and VC had the highest (>30). The vertebral canal surface area and the dural space: vertebral canal ratio may serve as reference values in future studies using this animal model.

Spinal epidural and synovial lipomatosis in a 3-year-old Eurasian dog receiving sustained steroid therapy.

This report describes a spinal cord epidural and synovial lipomatosis in a 3-year-old neutered male Eurasian dog. This dog presented for ambulatory paraparesis and was previously treated with immunosuppressive dosages of prednisolone for 2 years. Computed tomography (CT) myelography and magnetic resonnance imaging (MRI) images identified dorsal compression of the thoraco-lumbar spinal cord by hypertrophic epidural fat. Histological examination identified extensive well-differentiated mature adipose tissue in the subepithelial area of the tarsal synovium. Prednisolone is a reported predisposing factor in humans with lipomatosis.

Characteristic computed tomographic myelography findings in 23 Thoroughbred horses.

The purpose of this observational study was to determine the characteristic computed tomographic (CT) myelography findings of cervical vertebral stenotic myelopathy (CVSM) lesions in Thoroughbred horses. A total of 23 Thoroughbred horses (age range, 155-717 days on CT examination; mean, 410.9 days) were analyzed. All 23 Thoroughbred horses underwent unenhanced radiography, radiographic myelography, and CT myelography. Unenhanced radiographs were observed the presence of cervical vertebral malalignment and osseous lesions. Radiographic myelograms were observed for signs of cervical spinal cord compression; additionally, CT myelograms were used to detect cervical vertebral osseous lesions. Ventral compressions were frequently observed in the cranial cervical vertebrae (C2-C4), whereas dorsal compressions were frequently observed in the caudal cervical vertebrae (C5-C7). Furthermore, osseous lesions of the caudal articular process developed more frequently than those of the cranial articular process. CT myelography in Thoroughbred horses is a useful method for detecting CVSM changes.

An objective index for spinal cord compression on computed tomography in Thoroughbred horses.

BACKGROUND: Computed tomographic myelography can be a useful tool for evaluating vertebral canal stenosis. However, an index of spinal cord compression is yet to be established. OBJECTIVES: This observational descriptive study aimed to establish an index for spinal cord compression using computed tomography (CT). METHODS: Twenty-three Thoroughbred horses (age, 155-717 days; weight, 205-523 kg) with suspected cervical vertebral malformation were subjected to computed tomographic myelography in dorsal recumbency using large-bore gantry CT to define the entire cervical vertebrae from C1 to C7. Subsequently, the height of the spinal cord was measured in the sagittal plane reformatted using curved multi-planar reformation (MPR), thereby comparing it with stenotic ratio (i.e. dividing the area of spinal cord by that of the subarachnoid space) measured in the transverse plane. The measurement was performed at the level of each of six intervertebral spaces, for a total of 138 sites. Accordingly, the appropriate cut-off value for spinal cord height was determined using the receiver-operating characteristic curve, from which the area under the curve with 95% confidence interval was estimated. RESULTS: The spinal cord compression cut-off value was 7.06 mm, with an area under curve of 0.84. A weak relationship was observed between spinal cord height and stenotic ratio (R2  = 0.08, p < 0.05). CONCLUSIONS: Following curved MPR, a cut-off value of 7.06 mm may serve as an index for spinal cord compression.