Ratio Of Spinal Cord Research Articles

Determination of Fetal Spinal Cord Measurement for Every Gestation Age

Background and Hypothesis: 
 Tethered spinal cord is challenging to identify in fetuses. If untreated, tethered spinal cord can result in neurologic weakness and sensory loss in the lower half of the body. The goal of this study is to develop a library of normal ratios of the position of the conus medullaris relative to the spinal canal from normal fetal magnetic resonance imaging (MRI) examinations at each gestation age. This will allow for early identification of tethered spinal cord and timely intervention. We hypothesize that the ratios will decrease throughout pregnancy as the level of the conus medullaris rises. 
 Experimental Design or Project Methods: 
 In this pilot study, a retrospective review of fetal MRIs from patients between 20-38 weeks gestation age were examined. Exclusion criteria included fetuses with fetal spinal or central nervous system anomalies, VACTERL, ventral wall defects, scoliosis, and sacrococcygeal teratoma. The length from the fetal obex to the conus medullaris was measured and defined as the spinal cord length. The length of the obex to the caudal thecal sac was defined as the spinal canal length. The ratio of the spinal cord length to the spinal canal length was calculated. The ratios at each gestation age were compared using ANOVA (p < 0.05). 
 Results: 
 A total of 225 patients were reviewed. We observed a statistically significant decreasing trend in fetal spinal ratios from 20-38 weeks of gestation age. The average ratio at 20 weeks gestation age is 0.756 and at 38 weeks is 0.696. 
 Conclusion and Potential Impact: 
 This retrospective pilot study of fetal MRIs will establish reference values for the ratio of spinal cord to spinal canal lengths at progressing gestation ages. Ultimately, these ratios can establish normal values for identification of tethered spinal cord during the fetal period, thereby allowing early intervention to mitigate complications.

Analysis of Morphometric Parameters in Cervical Canal Stenosis on Neutral and Dynamic Magnetic Resonance Imaging.

A dynamic compression injury of the cervical spinal cord (SC) is widely accepted in the pathophysiology of cervical myelopathy. Flexion/extension magnetic resonance imaging (MRI) provides information on the dynamic cervical injury. We sought to compare morphometric parameters on neutral and flexion/extension MRI in cervical spondylotic myelopathy. Patients with cervical canal stenosis who had MRI in neutral, flexion, and extension positions were reviewed retrospectively. A morphometric comparison of following parameters at compression level was performed: SC area, cerebrospinal fluid (CSF) area, and CSF reserve ratio (CSF/CSF plus SC). Patients were classified according to the presence of high signal (HS) in SC, and predictors of HS were calculated by the use of logistic regression analysis. In total, 55 patients, 26 men, with mean age of 57 ± 13 were analyzed. Significant difference was found in mean CSF reserve ratio between flexion and extension (0.47 ± 0.18 vs. 0.40 ± 0.21, P < 0.05). SC area was significantly smaller in flexion (58.8 ± 13.3 mm2) than in both neutral (66.9 ± 22.3 mm2) and extension (68.3 ± 19.1 mm2). HS was found in 22 cases, and predictors of HS were smaller SC area on extension (odds ratio 1.46; 95% confidence interval 1.07-1.84) and smaller CSF plus SC area on flexion (OR 1.32; 95% confidence interval 1.06-1.45). Cut-off values on the receiver operating characteristic curve were 55 mm2 for SC and 99 mm2 for CSF plus SC area. Application of dynamic MRI in cervical stenosis reveals significant differences of both SC and CSF reserve ratio in flexion/extension and neutral positions. Patients with smaller SC area in extension and smaller CSF plus SC area in flexion have greater risk of HS on MRI.

Assessing denoising strategies to increase signal to noise ratio in spinal cord and in brain cortical and subcortical regions

Functional Magnetic Resonance Imaging (fMRI) based on Blood Oxygenation Level Dependent (BOLD) contrast has become one of the most powerful tools in neuroscience research. On the other hand, fMRI approaches have seen limited use in the study of spinal cord and subcortical brain regions (such as the brainstem and portions of the diencephalon). Indeed obtaining good BOLD signal in these areas still represents a technical and scientific challenge, due to poor control of physiological noise and to a limited overall quality of the functional series. A solution can be found in the combination of optimized experimental procedures at acquisition stage, and well-adapted artifact mitigation procedures in the data processing. In this framework, we studied two different data processing strategies to reduce physiological noise in cortical and subcortical brain regions and in the spinal cord, based on the aCompCor and RETROICOR denoising tools respectively. The study, performed in healthy subjects, was carried out using an ad hoc isometric motor task. We observed an increased signal to noise ratio in the denoised functional time series in the spinal cord and in the subcortical brain region.

New radiological parameters for the assessment of atlantoaxial instability in children with Down syndrome

To determine the normal values and usefulness of the C1/4 space available for spinal cord (SAC) ratio and C1 inclination angle, which are new radiological parameters for assessing atlantoaxial instability in children with Down syndrome. We recruited 272 children with Down syndrome (including 14 who underwent surgical treatment), and 141 children in the control group. All were aged between two and 11 years. The C1/4 SAC ratio, C1 inclination angle, atlas-dens interval (ADI), and SAC were measured in those with Down syndrome, and the C1/4 SAC ratio and C1 inclination angle were measured in the control group. The mean C1/4 SAC ratio in those requiring surgery with Down syndrome, those with Down syndrome not requiring surgery and controls were 0.63 (standard deviation (sd) 0.1), 1.15 (sd0.13) and 1.29 (sd 0.14), respectively, and the mean C1 inclination angles were -3.1° (sd10.7°), 15.8° (sd 7.3) and 17.2° (sd 7.3), in these three groups, respectively. The mean ADI and SAC in those with Down syndrome requiring surgery and those with Down syndrome not requiring surgery were 9.8 mm (sd 2.8) and 4.3 mm (sd 1.0), and 11.1 mm (sd 2.6) and 18.5 mm (sd 2.4), respectively. The normal values of the C1/4 SAC ratio and the C1 inclination angle were found to be about 1.2° and 15º, respectively. Cite this article: Bone Joint J 2016;98-B:1704-10.

Spinal cord morphology predicts curve progression in adolescent idiopathic scoliosis treated with bracing? A prospective cohort study with magnetic resonance imaging

Material and methods A total of 66 AIS girls with right-sided thoracic/thoracolumbar curves (mean age, 12.6 years; range, 10 -14 years) prescribed for bracing treatment were enrolled. Longitudinal follow-up at 6-month intervals was made beyond skeletal maturity. Demographic and anthropometric parameters, curve magnitude, menarche status, and Risser sign were assessed at each clinic visit. Bone mineral density (BMD) at femoral neck and MRI measurements including ratio of spinal cord to vertebral column length, ratio of anteroposterior (AP) and transverse (TS) diameter of cord, lateral cord space (LCS) ratio, cerebellar tonsil level, conus medullaris position were obtained at baseline. AIS girls were assigned into three groups according to bracing outcome: (A) Non-Progression (curvature increase =6 degree); (C) Progression with surgery indication (Cobb angle>=50 degree after skeletal maturity despite bracing). The predictors for curve progression were evaluated using univariate analysis and multivariate ordinal regression model. Results The average duration of follow-up was 3.4 years (range: 2.0-5.6 years). Of 66 AIS girls, there were 25 girls (38%) in group A, 21 girls (32%) in group B and 20 girls (30%) in group C, respectively. No significant intergroup differences were found in spinal cord length, cerebellar tonsil level and conus position (all P>0.05). Group C had significantly longer vertebral column length (P=0.026), smaller cord-vertebral length ratio (P=0.012), and higher AP/TS cord ratio (P=0.015) as compared to group A, while LCS ratio in group C was significantly increased when compared with both group A (P=0.005) and group B (P=0.016). In final regression model, four significant independent predictors including LCS ratio (Odds Ratio (OR): 3.053 [95% CI: 1.117-8.343, P=0.030]), initial curve magnitude (OR: 1.054 [95% CI: 1.004-1.108, P=0.036]), menarche age (OR: 2.126 [95% CI: 1.143-3.952, P=0.017]), BMD (OR: 3.009 [95% CI: 1.175 7.705, P=0.022]), and one marginally significant predictor e.g. AP/TS cord ratio (OR: 1.841[95% CI: 0.955-3.55, P=0.068]) were obtained.

Effects of Clematidis Radix Pharmacopuncture Injected at Sinsu(BL23) on Neuropathic Pain in Rats※

Objectives : The purpose of this study is to examine if Clematidis Radix(CR) pharmacopuncture may be effective to the neuropathic pain(mechanical allodynia) in a rat model of neuropathic pain. Methods : To produce the model of neuropathic, L5 spinal nerve was ligated by 6-0 silk thread. After neuropathic surgery, the author examined if the animals exhibited the plantar withdrawal response of allodynia. The plantar withdrawal response was assessed by dynamic plantar aesthesiometer three days after the neuropathic surgery, CR pharmacopuncture was injected at BL23 1time/week for 6 weeks. After that, the author examined the plantar withdrawal response of rats’ leg by dynamic plantar aesthesiometer. And also the author examined mGluR5, Bax, Bcl-2, Bax/Bcl-2 ratio in spinal cord, and c-Fos. Also the author observed the change of aspartate aminotransferase(AST), alanine aminotransferase(ALT) count in the blood serum of neuropathic rats. Results : 1. The withdrawal response of allodynia decreased in the PT3, PT4 group as compared with control group. 2. The mGluR5 increased in the PT1, PT2, PT3, and PT4 group. 3. The Bax and Bax/Bcl-2 ratio decreased in the PT4 group. 4. The c-Fos increased in the PT1 group, and decreased in the PT4 group. 5. The changes of AST in blood serum decreased in the every group excluded control group and the changes of ALT in blood serum isn’t shown the signigicant change. Conclusions : These results are suggested that CR pharmacopuncture at BL23 decreased mechanical allodynia, can act on anti-apoptotic, neuroprotective effects and liver fuction in the model of neuropathic pain.

Novel 2 radiographical measurements for atlantoaxial instability in children with Down syndrome.

A retrospective case-control study. To assess the usefulness and reproducibility of 2 novel safe and simple radiographical measurements for atlantoaxial instability in children with Down syndrome. In pediatric atlantoaxial instability, early diagnosis is important for improved outcomes because of poor postoperative recovery in progressed neurological symptoms. Conventional dynamic radiography of the cervical spine is associated with a potential risk of worsening neurological symptoms. We retrospectively reviewed the medical records of 50 patients (24 boys and 26 girls) with atlantoaxial instability associated with Down syndrome. Of the 50 children, 11 had undergone and 4 had been scheduled for surgery (surgical group). In this investigation, in addition to the atlas-dens interval (ADI) and space available for spinal cord (SAC), we measured C1 inclination angle and C1/4 SAC ratio on lateral radiographs of the cervical spine in the neutral position. To assess the diagnostic abilities of these indices to determine indication for surgery, receiver operating characteristic analysis of each index was performed, and their diagnostic abilities were compared using the area under the receiver operating characteristic curve. Moreover, we assessed reproducibility of our 2 proposed indices. The discriminatory abilities of C1/4 SAC ratio (area under the receiver operating characteristic curve, 1.00) and C1 inclination angle (0.91) were comparable with those of ADI (0.98) and SAC (0.95). For the interobserver and intraobserver reliability of the novel indices, the correlation coefficients were in the range from 0.88 to 0.99. Correlation was observed between the ADI and C1/4 SAC ratio (r = 0.507, P < 0.01) and between the ADI and C1 inclination angle (r = 0.407, P < 0.01). The diagnostic abilities of the 2 novel radiographical measurements were comparable with those of ADI and SAC. Moreover, these novel measurements can be obtained safely on lateral radiographs of the cervical spine in the neutral position. 4.

Prevalence and heritability of symptomatic syringomyelia in Cavalier King Charles Spaniels and long-term outcome in symptomatic and asymptomatic littermates.

BackgroundSyringomyelia (SM) is common in the Cavalier King Charles Spaniel (CKCS). Dogs with syringes express clinical signs or might be clinically silent.ObjectivesTo investigate the prevalence and heritability of symptomatic SM, the association between clinical signs and magnetic resonance imaging (MRI) findings, and long‐term outcome.AnimalsAll CKCS registered in the Danish Kennel Club in 2001 (n = 240).MethodsA cross‐sectional questionnaire‐based prevalence study validated by telephone interviews and clinically investigated clinical signs of SM. Dogs were 6 years at the time of investigation. A prospective observational litter study including clinical investigations, MRI and 5‐year follow‐up of symptomatic and asymptomatic siblings. Heritability was estimated based on the scale of liability in the study population and litter cohort.ResultsThe cross‐sectional study estimated a prevalence of symptomatic SM at 15.4% in the population. Thirteen symptomatic and 9 asymptomatic siblings participated in the litter study. Spinal cord syringes were confirmed in 21 of 22 littermates (95%). Syrinx diameter and mean syrinx : spinal cord ratio were significantly correlated with clinical signs (P < .01). Estimated heritability of symptomatic SM was 0.81. Symptomatic SM motivated euthanasia in 20%. Dogs with syringes, which expressed no clinical signs at the age of 6, remained asymptomatic in 14/15 cases (93%).Conclusions and Clinical ImportanceThe prevalence of symptomatic SM is high and genetics have a high impact on clinical disease expression. Further investigations of factors influencing the outbreak threshold of clinical signs of SM are desirable.

Computed tomographic measurements with and without myelography to characterise thoracolumbar extruded disc herniation

To determine association between computed tomography measurements of spinal cord compression and postoperative outcome. A retrospective review of medical records of dogs presenting with intervertebral disease. Data were collected with a minimum of 2 years follow-up period. Computed tomography morphometric indices, particularly the ratio of spinal cord or herniated disc to vertebral canal dimensions, were obtained from survey and myelogram computed tomographic images. The pattern of disc disease was scored as single or continuous (multiple herniated discs), and was compared to postoperative outcome. Fifty-two dogs were included. There was no significant correlation between the degree of spinal cord compression and postoperative outcome. However, postoperative outcome differed significantly between dogs with single or continuous patterns of disc disease (P=0·001). Of those with single patterns, 75% had a postoperative outcome score greater than 75% while 75% of continuous pattern cases had scores lower than 83%. Simple observation of the pattern of disc disease as revealed by computed tomography could be used as a prognostic indicator. The outcome tends to be better for single patterns of disc disease, whereas the outcome was poor for most cases with continuous patterns.

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We studied about compression ratio of spinal cord on computed tomographic spondylotic myelopathy. We found that some cases with compression of below 40% ratio did not well. Some factors influencing on the postoperative results exist: for example, period until operation, canal diameter and heavy neurological sign. By compression ratio and those factors, we may be able to presuppose the prognosis of patients with cervical spondylotic myelopathy.