Does the type of T2-weighted hyperintensity influence surgical outcome in patients with cervical spondylotic myelopathy? A review. Eur Spine J. 2013;22:96-106. [PMID: 22926434 DOI: 10.1007/s00586-012-2483-9]

T2-weighted MRI high signal in cervical spondylotic myelopathy is associated with dynamic change

OBJECTIVE

The cervical spine's mobility affects the compression level of the cervical cord which varies with dynamic positioning. High signal on MRI T2-weight imaging (MRI-T2WI) of the cervical cord indicates a poorer prognosis. This study investigates the relationship between high-signal intensity on MRI-T2WI and cervical dynamic change using kinematic MRI. The objective of this study was to explore changes in the degree of cervical spinal cord compression during flexion-extension motions and identify risk factors linked to the occurrence of high signals.

MATERIALS AND METHODS

We collected data on patients who underwent surgical treatment for cervical spondylotic myelopathy (CSM) in our department from 2023 to 2024. Patients were classified into two groups based on high-intensity signal presence: the high-signal group and non-high-signal group. Using kinematic MRI, the area and width of cervical cord compression in the responsible segment were measured in the axial and sagittal positions. Differences between the two groups were assessed using univariate analysis, binary logistic analysis, receiver operating characteristic (ROC) curve, and restricted cubic spline (RCS) regression model.

RESULTS

A total of 40 patients in the high-signal group and 30 in the non-high-signal group were included in the study. There was no significant difference in baseline characteristics between two groups. The degree of cord compression was remarkably increased in both groups with cervical ranging from flexion to extension. Additionally, the neutral position and extension compression degrees (area and width) were significantly greater in the high-signal group than in the non-high-signal group, indicating that stenosis is a risk factor for high-signal occurrence. Furthermore, the degree of dynamic compression change of kinematic MRI was significantly higher in the high-signal group compared to the non-high-signal group. Statistical analysis confirmed that cervical dynamic change was an independent risk factor for high-signal occurrence. The RCS curve demonstrated that the incidence of high signal significantly increased when the compression degree of extension/flexion exceeded 1.4.

CONCLUSION

Cervical cord compression worsens with cervical dynamic change from flexion to extension. The degree of compression change is considered a risk factor for high signals on MRI-T2WI. An extension/flexion value greater than 1.4 indicates an increased likelihood of a high-signal occurrence.

Does Elevated Mean-Arterial Pressure Lead to Better Outcomes in Degenerative Cervical Myelopathy?- A Prospective, Pilot Randomized Control Trial

Study designRandomized Control Trial.ObjectiveDCM refers to compression of spinal cord either due to static/dynamic causes or commonly, a result of combination of both. Number of variables exist, which determine prognosis post-surgery. Role of intra-operative blood pressure has not been analyzed in depth in current literature. Elevating MAP post SCI is widely practiced and forms a recommendation of AANS/CNS Joint Committee Guidelines. This led us to investigate role played by elevated MAP during surgery for DCM, in order to optimize outcomes.MethodsThis prospective randomized comparative pilot study was conducted at a tertiary care spine centre. 84 patients were randomly divided in two groups. Group 1 had intra-operative MAP in normal range. Group 2, had intra-operative BP 20 mmHg higher than preoperative average MAP with a variation of + 5 mmHg. Outcomes were recorded at 3 months, 6 months and 1 year by mJOA, VAS and ASIA scale.ResultsNeurological improvement was documented in 19/30 (63.3%) patients of hypertensive group compared to 16/30 (53.3%) patients of normotensive group. Improvements in mJOA scores were better for hypertensive group during the 1-year follow-up. Improvement in VAS scores were comparable between two groups, but at 1-year follow-up the VAS score of hypertensive groups was significantly lower.ConclusionMAP should be individualized according to preoperative average blood pressure assessment of patient. Keeping intraoperative MAP at higher level (preoperative MAP + 20 mmHg) during surgery for DCM can result in better outcomes.

Changes in Intramedullary Increased Signal Intensity on Axial T2-weighted MRI After Laminoplasty for Cervical Spondylotic Myelopathy: A 10-year Follow-up Study

STUDY DESIGN

A retrospective study.

OBJECTIVE

To investigate whether the preoperative classification and changes in the intramedullary increased signal intensity (ISI) on axial T2-weighted magnetic resonance imaging (MRI) reflect the postoperative functional outcome in patients after laminoplasty for cervical spondylotic myelopathy (CSM).

SUMMARY OF BACKGROUND DATA

Although patients with CSM exhibit ISI on axial MRI, the association between ISI (preoperative classification and changes) and surgical outcomes has not been investigated.

PATIENTS AND METHODS

We retrospectively included patients with CSM who underwent MRI preoperatively and at least 10 years postoperatively after laminoplasty between January 2009 and December 2010. According to axial images for the cervical compressive myelopathy (Ax-CCM) system, the ISI on axial images was classified as follows: type 0, normal; type 1, diffuse; type 2, fuzzy focal; and type 3, discrete focal. Functional outcomes, as measured by the Japanese Orthopaedic Association (JOA) score and JOA recovery rate, were evaluated based on the Ax-CCM classification.

RESULTS

Forty-three patients were enrolled. The mean follow-up time was 11.0±1.0 years. At the final follow-up, postoperative changes in the type of ISI were observed in 62.8% of patients. The type of ISI improved in 5 patients (11.6%), remained unchanged in 16 patients (37.2%), and worsened in 22 patients (51.2%). Patients with preoperative type 2 ISI had worse postoperative JOA scores and JOA recovery rates than those with other types. A worse ISI type was related to a lower postoperative JOA score and a lower recovery rate at the final follow-up.

CONCLUSIONS

Type 2 ISI was associated with poor postoperative symptoms and low postoperative function improvement. ISI changed after laminoplasty in 27 patients (62.8%), and worsened ISI was related to poor surgical outcomes.

Machine-learning-based prediction by stacking ensemble strategy for surgical outcomes in patients with degenerative cervical myelopathy

BACKGROUND

Machine learning (ML) is extensively employed for forecasting the outcome of various illnesses. The objective of the study was to develop ML based classifiers using a stacking ensemble strategy to predict the Japanese Orthopedic Association (JOA) recovery rate for patients with degenerative cervical myelopathy (DCM).

METHODS

A total of 672 patients with DCM were included in the study and labeled with JOA recovery rate by 1-year follow-up. All data were collected during 2012-2023 and were randomly divided into training and testing (8:2) sub-datasets. A total of 91 initial ML classifiers were developed, and the top 3 initial classifiers with the best performance were further stacked into an ensemble classifier with a supported vector machine (SVM) classifier. The area under the curve (AUC) was the main indicator to assess the prediction performance of all classifiers. The primary predicted outcome was the JOA recovery rate.

RESULTS

By applying an ensemble learning strategy (e.g., stacking), the accuracy of the ML classifier improved following combining three widely used ML models (e.g., RFE-SVM, EmbeddingLR-LR, and RFE-AdaBoost). Decision curve analysis showed the merits of the ensemble classifiers, as the curves of the top 3 initial classifiers varied a lot in predicting JOA recovery rate in DCM patients.

CONCLUSIONS

The ensemble classifiers successfully predict the JOA recovery rate in DCM patients, which showed a high potential for assisting physicians in managing DCM patients and making full use of medical resources.

Magnetic Resonance Imaging-CCCFLS Scoring System: Toward Predicting Clinical Symptoms and C5 Paralysis

STUDY DESIGN

A retrospective study.

OBJECTIVE

To develop a new MRI scoring system to assess patients' clinical characteristics, outcomes and complications.

METHODS

A retrospective 1-year follow-up study of 366 patients with cervical spondylosis from 2017 to 2021. The CCCFLS scores (cervical curvature and balance (CC), spinal cord curvature (SC), spinal cord compression ratio (CR), cerebrospinal fluid space (CFS). Spinal cord and lesion location (SL). Increased Signal Intensity (ISI) were divided into Mild group (0-6), Moderate group (6-12), and Severe group (12-18) for comparison, and the Japanese Orthopaedic Association (JOA) scores, visual analog scale (VAS), numerical rating scale (NRS), Neck Disability Index (NDI) and Nurick scores were evaluated. Correlation and regression analyses were performed between each variable and the total model in relation to clinical symptoms and C5 palsy.

RESULTS

The CCCFLS scoring system was linearly correlated with JOA, NRS, Nurick and NDI scores, with significant differences in JOA scores among patients with different CC, CR, CFS, ISI scores, with a predictive model (R2 = 69.3%), and significant differences in preoperative and final follow-up clinical scores among the 3 groups, with a higher rate of improvement in JOA in the severe group (P < .05), while patients with and without C5 paralysis had significant differences in preoperative SC and SL (P < .05).

CONCLUSION

CCCFLS scoring system can be divided into mild (0-6). moderate (6-12), severe (12-18) groups. It can effectively reflect the severity of clinical symptoms, and the improvement rate of JOA is better in the severe group, while the preoperative SC and SL scores are closely related to C5 palsy.

LEVEL OF EVIDENCE

III.

Correlation of spinal cord compression angle and increased signal intensity on MRI in patients with ossification of posterior longitudinal ligament

We retrospectively investigated the correlation between the spinal cord compression angle and increased signal intensity (ISI) in 118 patients with ossification of the posterior longitudinal ligament (OPLL). Patients were analyzed based on the presence and shape of ISI on magnetic resonance imaging. Various indicators, including the spinal cord compression angle, were measured through imaging examinations. Spearman's correlation and logistic regression were used for analyses. Significant positive correlations were observed between the ISI grade and the spinal cord compression angle, maximum spinal canal occupying rate, cervical range of motion, and segmental range of motion. The spinal cord compression ratio and Japanese Orthopaedic Association (JOA) score were negatively correlated with the ISI grade. Regression analysis revealed that the spinal cord compression angle and JOA scores were independent factors that significantly influenced ISI grade. The odds ratio of ISI was 3.858 (95% confidence interval: 0.974-15.278) when comparing the highest and lowest quartiles of the spinal cord compression angle. Patients with a spinal cord compression angle > 35° had more severe imaging manifestations. Thus, a spinal cord compression angle > 35° could serve as a significant indicator of OPLL severity, and greater attention should be focused on treating patients with larger spinal cord compression angles.

Spinal column radiological factors associated with increased spinal cord intramedullary signal intensity - A study evaluating aging spinal cord's relation to spinal disc degeneration

PURPOSE

Increased intramedullary signal intensity (IISI) on T2 weighted MRI scan (T2WI) can be a radiological feature of spinal cord degeneration. However, the association of IISI to degeneration of the spinal column that protects the spinal cord remains unclear. The purpose of this study was to determine the prevalence of IISI and analyze the independent relationship between IISI and cervical degenerative parameters on X-ray and magnetic resonance imaging (MRI).

METHODS

A retrospective review of MRI, X-ray, and radiology data (n = 144) adult patients with both cervical MRI and X-ray scans was conducted. A total of 39 (27 %) patients with IISI was identified. The remaining 105 patients without IISI made up the control group.

RESULTS

IISI was most frequent in C6-C7 cervical levels. The likelihood of having IISI was 1.947 (Exp(B) 1.947, 95 %CI [1.004-3.776]) times higher in segmental levels with facet joint degeneration. There was an increased likelihood of IISI within the spinal cord with increasing age (Exp(B) 1.034, 95 %CI [1.008-1.060]), maximum spinal cord compression (MSCC) (Exp(B) 1.038, 95 %CI [1.003-1.075]), rotational angle (Exp(B) 1.082, 95 %CI [1.020-1.148]) and posterior disc herniation width (Exp(B) 1.333, 95 %CI [1.017-1.747]) and decreasing Torg-Pavlov ratio (Exp(B) 0.010, 95 %CI [0.001-0.068]).

CONCLUSION

IISI was independently associated with increased age, facet joint degeneration, MSCC, rotational angle, posterior herniation width and decreasing Torg-Pavlov angle. Radiologicaldegenerative changesassociated with IISI indicates a potential for identifying predictors of age related spinal cord morphological changes in DCM, which may allow for early intervention strategies in the future.

Developing predictive models for surgical outcomes in patients with degenerative cervical myelopathy: a comparison of statistical and machine learning approaches

BACKGROUND CONTEXT

Machine learning (ML) is widely used to predict the prognosis of numerous diseases.

PURPOSE

This retrospective analysis aimed to develop a prognostic prediction model using ML algorithms and identify predictors associated with poor surgical outcomes in patients with degenerative cervical myelopathy (DCM).

STUDY DESIGN

A retrospective study.

PATIENT SAMPLE

A total of 406 symptomatic DCM patients who underwent surgical decompression were enrolled and analyzed from three independent medical centers.

OUTCOME MEASURES

We calculated the area under the curve (AUC), classification accuracy, sensitivity, and specificity of each model.

METHODS

The Japanese Orthopedic Association (JOA) score was obtained before and 1 year following decompression surgery, and patients were grouped into good and poor outcome groups based on a cut-off value of 60% based on a previous study. Two datasets were fused for training, 1 dataset was held out as an external validation set. Optimal feature-subset and hyperparameters for each model were adjusted based on a 2,000-resample bootstrap-based internal validation via exhaustive search and grid search. The performance of each model was then tested on the external validation set.

RESULTS

The Support Vector Machine (SVM) model showed the highest predictive accuracy compared to other methods, with an AUC of 0.82 and an accuracy of 75.7%. Age, sex, disease duration, and preoperative JOA score were identified as the most commonly selected features by both the ML and statistical models. Grid search optimization for hyperparameters successfully enhanced the predictive performance of each ML model, and the SVM model still had the best performance with an AUC of 0.93 and an accuracy of 86.4%.

CONCLUSIONS

Overall, the study demonstrated that ML classifiers such as SVM can effectively predict surgical outcomes for patients with DCM while identifying associated predictors in a multivariate manner.

Clinicoradiological Risk Factors Associated with Inability to Achieve Minimum Clinically Important Difference in Operated Cases of Cervical Spondylotic Myelopathy

STUDY DESIGN

This is a retrospective cohort study.

PURPOSE

This study aimed to identify the clinicoradiological risk factors associated with the inability to achieve minimum clinically important difference (MCID) on the modified Japanese Orthopaedic Association (mJOA) Scale in operated cases of cervical spondylotic myelopathy (CSM).

OVERVIEW OF LITERATURE

Only a few studies have evaluated the outcomes of surgery performed for CSM using MCID on the mJOA scale.

METHODS

We analyzed 124 operated CSM cases from March 2019 to April 2021 for preoperative clinical features, cervical sagittal radiographic parameters, and magnetic resonance imaging (MRI) signal intensities (SI). The risk factors associated with missing the MCID (poor outcome) on mJOA at the final follow-up were identified using binary logistic regression. Multivariate analysis was used to find significant risk factors, and odds ratios (OR) were computed.

RESULTS

A total of 110 men (89.2%) and 14 women (10.8%) with an average age of 53.5±13.2 years were included in the analysis. During the last follow-up, 89 cases (72.1%) achieved MCID (meaningful gains following surgery) while 35 (27.9%) could not. The final model identified the following parameters as significant risk factors for poor outcome: increased duration of symptoms (OR, 6.77; p=0.001), lower preoperative mJOA scale (OR, 0.75; p=0.029), the presence of multilevel T2-weighted (T2W) MRI SI (OR, 4.79; p=0.004), and larger change in cervical sagittal vertical axis (ΔcSVA) (OR, 1.06; p=0.013). Also, an increase in cSVA postoperatively correlated with a reduced functional recovery rate (r=-0.4, p<0.001).

CONCLUSIONS

Surgery for CSM leads to significant functional benefits. However, poorer outcomes are observed in cases of greater duration of symptoms, higher preoperative severity with multilevel T2W MRI SI, and a larger increase in the postoperative cSVA (sagittal imbalance).

Automated signal intensity analysis of the spinal cord for detection of degenerative cervical myelopathy - a matched-pair MRI study

PURPOSE

Detection of T2 hyperintensities in suspected degenerative cervical myelopathy (DCM) is done subjectively in clinical practice. To gain objective quantification for dedicated treatment, signal intensity analysis of the spinal cord is purposeful. We investigated fully automated quantification of the T2 signal intensity (T2-SI) of the spinal cord using a high-resolution MRI segmentation.

METHODS

Matched-pair analysis of prospective acquired cervical 3D T2-weighted sequences of 114 symptomatic patients and 88 healthy volunteers. Cervical spinal cord was segmented automatically through a trained convolutional neuronal network with subsequent T2-SI registration slice-by-slice. Received T2-SI curves were subdivided for each cervical level from C2 to C7. Additionally, all levels were subjectively classified concerning a present T2 hyperintensity. For T2-positive levels, corresponding T2-SI curves were compared to curves of age-matched volunteers at the identical level.

RESULTS

Forty-nine patients showed subjective T2 hyperintensities at any level. The corresponding T2-SI curves showed higher signal variabilities reflected by standard deviation (18.51 vs. 7.47 a.u.; p < 0.001) and range (56.09 vs. 24.34 a.u.; p < 0.001) compared to matched controls. Percentage of the range from the mean absolute T2-SI per cervical level, introduced as "T2 myelopathy index" (T2-MI), was correspondingly significantly higher in T2-positive segments (23.99% vs. 10.85%; p < 0.001). ROC analysis indicated excellent differentiation for all three parameters (AUC 0.865-0.920).

CONCLUSION

This fully automated T2-SI quantification of the spinal cord revealed significantly increased signal variability for DCM patients compared to healthy volunteers. This innovative procedure and the applied parameters showed sufficient diagnostic accuracy, potentially diagnosing radiological DCM more objective to optimize treatment recommendation.

TRIAL REGISTRATION

DRKS00012962 (17.01.2018) and DRKS00017351 (28.05.2019).

Blood-spinal cord barrier disruption in degenerative cervical myelopathy

Degenerative cervical myelopathy (DCM) is the most prevalent cause of spinal cord dysfunction in the aging population. Significant neurological deficits may result from a delayed diagnosis as well as inadequate neurological recovery following surgical decompression. Here, we review the pathophysiology of DCM with an emphasis on how blood-spinal cord barrier (BSCB) disruption is a critical yet neglected pathological feature affecting prognosis. In patients suffering from DCM, compromise of the BSCB is evidenced by elevated cerebrospinal fluid (CSF) to serum protein ratios and abnormal contrast-enhancement upon magnetic resonance imaging (MRI). In animal model correlates, there is histological evidence of increased extravasation of tissue dyes and serum contents, and pathological changes to the neurovascular unit. BSCB dysfunction is the likely culprit for ischemia-reperfusion injury following surgical decompression, which can result in devastating neurological sequelae. As there are currently no therapeutic approaches specifically targeting BSCB reconstitution, we conclude the review by discussing potential interventions harnessed for this purpose.

Classification of cervical disc herniation myelopathy or radiculopathy: a magnetic resonance imaging-based analysis

Background

Preoperative magnetic resonance imaging (MRI) can clearly show the location and level of disc herniation. When the symptoms are consistent with the Prominent segments, surgical treatment can be indicated. However, the varied extents of the protruding masses in cervical disc herniation (CDH) have been rarely reported. This study aimed to characterize the severity of CDH and to develop a reproducible grading and zoning system for cervical disc degeneration.

Methods

A total of 200 patients who presented with single CDH and underwent MRI/computed tomography (CT) scans were enrolled in this prospective study between 2018 and 2021. A total of 170 cervical discs were graded according to MRI by 3 spine surgeons in a blinded fashion. CDHs were graded 1-3, with regions A-C. All patients with grade 1 and mild C symptoms were excluded. The foramen facet spinal (FFS) classification based on MRI Japanese Orthopedic Association (JOA) scores and the incidence of complications were evaluated and analyzed, and follow-up outcomes were assessed.

Results

Areas 2-A, 2-B, and 1-C had high motor function scores, areas 2-A, 3-A, and 2-AB had high sensory scores, but areas 3-AB and 3-A had low bladder function scores. Areas 3-AB had the most severe symptoms and the lowest scores. Area 1-C showed neurogenic abnormal sensation and higher visual analog scale (VAS) scores. A good/excellent outcome as indicated by the JOA score was 94.70% at 3 months and 92.35% at 1 year in 170 patients. The complication rate was 9.41%. The diagnostic coefficient of the FFS classification was 0.888, P<0.001.

Conclusions

The FFS classification is an objective scoring system that can be applied similarly by multiple examiners and is correlated with clinical symptoms.

Influence of Preoperative Sagittal Alignment on Functional Recovery in Operated Cases of Cervical Spondylotic Myelopathy

Objective  We examine the influence of preoperative cervical sagittal curvature (lordotic or nonlordotic) on the functional recovery of surgically managed cases of cervical spondylotic myelopathy (CSM). The impact of sagittal alignment on the functional improvement of operated CSM cases has not been thoroughly investigated. Materials and Methods  We did retrospective analysis of consecutively operated cases of CSM from March 2019 to April 2021. Patients were grouped into two categories: lordotic curvature (with Cobb angle > 10 degrees) and nonlordotic curvature (including neutral [Cobb angle 0-10 degrees] and kyphotic [Cobb angle < 0 degrees]). Demographic data, and preoperative and postoperative functional outcome scores (modified Japanese Orthopaedic Association [mJOA] and Nurick grade) were analyzed for dependency on preoperative curvature, and correlations between outcomes and sagittal parameters were assessed. Results  In the analysis of 124 cases, 63.1% (78 cases) were lordotic (mean Cobb angle of 23.57 ± 9.1 degrees; 11-50 degrees) and 36.9% (46 cases) were nonlordotic (mean Cobb angle of 0.89 ± 6.5 degrees; -11 to 10 degrees), 32 cases (24.6%) had neutral alignment, and 14 cases (12.3%) had kyphotic alignment. At the final follow-up, the mean change in mJOA score, Nurick grade, and functional recovery rate (mJOArr) were not significantly different between the lordotic and nonlordotic group. In the nonlordotic group, cases with anterior surgery had a significantly better mJOArr than those with posterior surgery ( p  = 0.04), whereas there was similar improvement with either approach in lordotic cases. In the nonlordotic group, patients who gained lordosis (78.1%) had better recovery rates than those who had lost lordosis (21.9%). However, this difference was not statistically significant. Conclusion  We report noninferiority of the functional outcome in the cases with preoperative nonlordotic alignment when compared with those with lordotic alignment. Further, nonlordotic patients who were approached anteriorly fared better than those approached posteriorly. Although increasing sagittal imbalance in nonlordotic spines portend toward higher preoperative disability, gain in lordosis in such cases may improve results. We recommend further studies with larger nonlordotic subjects to elucidate the impact of sagittal alignment on functional outcome.

Posterior Hybrid Technique for the Treatment of Traumatic Cervical Spinal Cord Injury with High Signal Intensity on T2WI

Objective

To evaluate the efficacy of the posterior hybrid technique (PHT) for the treatment of traumatic cervical spinal cord injury without vertebral fracture or dislocation with high signal intensity on T2WI (CSCIH).

Methods

A comparative analysis of clinical efficacy between CSCIH patients who underwent anterior decompression and fusion (ADF) surgery and those who underwent PHT surgery was retrospectively conducted. Demographic characteristics, cervical range of motion (CRM), cross-sectional area of spinal cord (CSASC), spinal canal area residual rate (SCARR), high signal intensity ratio (HSIR), Cervical Japanese Orthopedic Association (CJOA) score, and neck disability index (NDI) were assessed.

Results

Forty-three CSCIH cases with PHT and 46 CSCIH cases with ADF were collected from January 2013 to January 2017. The CRM in patients with PHT was superior to that in patients with ADF at the final follow-up (64.21 ± 18.46° vs. 48.71 ± 19.34°, p = 0.0002). The SCARR also showed greater improvements in the PHT group than in the ADF group (final follow-up: 93.54 ± 11.09% vs. 88.13 ± 10.84%, p = 0.022). Both groups indicated significant improvements in the CSASC and HSIR (p < 0.05); however, no significant differences were observed between the two groups. All patients showed improvements in the CJOA score and the NDI after surgery (p < 0.05). At the 6-month follow-up, the ADF group had better NDI scores than the PHT group (31.17 ± 10.42 vs. 36.78 ± 9.65, p = 0.010), whereas the PHT group exhibited better improvements than the ADF group at the final follow-up (66.86 ± 9.28% vs. 57.67 ± 10.22%, p < 0.0001).

Conclusion

The PHT was as effective as ADF in the treatment of CSCIH, whereas the PHT was superior in the improvement of patients' health-related quality of life and in CRM preservation during the long-term follow-up.

Correlation between "Snake-Eyes" Sign and Role of Surgery with a Focus on Postoperative Outcome: A Systematic Review

(1) Background: The "snake-eyes" sign represents a unique finding characterized by bilateral hyperintense symmetric, circular, or ovoid foci on T2-weighted MRI sequences in the anterior horn cells of the spinal cord. There are conflicting opinions as some authors affirm that it does not affect the prognosis of cervical myelopathy while other papers emphasize the opposite, stating how the "snake-eyes" sign constitutes an irreversible lesion and a predictor of poor prognosis. This systematic review evaluates the correlation between the "snake-eyes" sign and the prognosis of cervical myelopathy after surgery including anterior and/or posterior approaches; (2) Methods: A systematic literature review was conducted following the PRISMA statement and a total of seven papers were included; (3) Results: A total of 419 patients were evaluated, with a mean age of 55.72 ± 14.38 years. After surgery, 26.01% of patients experienced a significant clinical improvement, while in 61.81%, there was no significant improvement. In particular, 144 of 196 patients (73.5%) treated through an anterior approach and 114 of 223 (51.1%) that underwent a posterior approach, did not present a significant improvement. Furthermore, in 12.17% of patients, the postoperative outcome was not reported, leading to a high risk of bias in the assessment of the prognostic significance of the "snake-eyes" appearance; (4) Conclusions: The "snake-eyes" sign is usually considered as an unfavorable predictive marker for myelopathic surgical patients, but the pathophysiology is still unclear, and the results have not yet reached unified levels of evidence.

Update of the Natural History, Pathophysiology, and Treatment Strategies of Degenerative Cervical Myelopathy: A Narrative Review

Cervical myelopathy is a clinical syndrome resulting in symptoms of neurologic deficits due to prolonged spinal cord compression or ischemia in the cervical spine. Spinal cord compression can be caused by ossification of the posterior longitudinal ligament and hypertrophy of ligamentun flavum in addition to degenerative cervical spondylosis, degenerative disc disease, and progressive cervical kyphosis. Degenerative cervical myelopathy (DCM) is a series of disease entities caused by spinal cord compression by various nontraumatic and non-infectious causes. The pathophysiology of DCM includes spinal cord structure and function abnormalities caused by both static and dynamic factors. Surgical decompression for patients with moderate to severe cervical myelopathy not only inhibits the progression of neurological deterioration, but also improves functional status, pain, and quality of life. However, the role of nonsurgical treatment in patients with mild spinal cord compression is controversial. In general, patients with cervical myelopathies who do not undergo surgery have a poor prognosis. Appropriate surgical treatment is recommended when spinal cord compression is confirmed on image study in patients with reasonable symptoms of cervical myelopathy. The patient's overall health, degree of compression, presence of concurrent cervical radiculopathy, and cervical spine alignment, in addition to lesion location and etiology, should be considered when determining an appropriate surgical procedure. This review covers the updated issues, including pathophysiology, clinical manifestations, differential diagnosis, and available treatments for DCM.

New Imaging Modalities for Degenerative Cervical Myelopathy

INTRODUCTION

Degenerative cervical myelopathy (DCM) is defined as dysfunction of the spinal cord as a result of compression from degenerative changes to surrounding joints, intervertebral disks, or ligaments. Symptoms can include upper extremity numbness and diminished dexterity, difficulty with fine manipulation of objects, gait imbalance, and incoordination, and compromised bowel and bladder function. Accurate diagnosis and evaluation of the degree of impairment due to degenerative cervical myelopathy remain a challenging clinical endeavor requiring a thorough and accurate history, physical examination, and assessment of imaging findings.

METHODS

A narrative review is presented summarizing the current landscape of imaging modalities utilized in DCM diagnostics and the future direction of research for spinal cord imaging.

RESULTS AND DISCUSSION

Current imaging modalities, particularly magnetic resonance imaging and, to a lesser extent, radiographs/CT, offer important information to aid in decision making but are not ideal as stand-alone tools. Newer imaging modalities currently being studied in the literature include diffusion tensor imaging, MR spectroscopy, functional magnetic resonance imaging, perfusion imaging, and positron emission tomography. These newer imaging modalities attempt to more accurately evaluate the physical structure, intrinsic connectivity, biochemical and metabolic function, and perfusion of the spinal cord in DCM. Although there are still substantial limitations to implementation, future clinical practice will likely be revolutionized by these new imaging modalities to diagnose, localize, surgically plan and manage, and follow patients with DCM.

Differences between spinal cord injury and cervical compressive myelopathy in intramedullary high-intensity lesions on T2-weighted magnetic resonance imaging: A retrospective study

Increases in aging populations have raised the number of patients with cervical spinal cord injury (SCI) without fractures due to compression of the cervical spinal cord. In such patients, it is necessary to clarify whether SCI or cervical compressive myelopathy (CCM) is the cause of disability after trauma. This study aimed to clarify the differences in magnetic resonance imaging (MRI) features between SCI and CCM. Overall, 60 SCI patients and 60 CCM patients with intramedullary high-intensity lesions on T2-weighted MRI were included in this study. The longitudinal lengths of the intramedullary T2 high-intensity lesions were measured using sagittal MRI sections. Snake-eye appearance on axial sections was assessed as a characteristic finding of CCM. The T2 values of the high-intensity lesions and normal spinal cords at the first thoracic vertebra level were measured, and the contrast ratio was calculated using these values. The longitudinal length of T2 high-intensity lesions was significantly longer in SCI patients than in CCM patients. Snake-eye appearance was found in 26 of the 60 CCM patients, but not in SCI patients. On both the sagittal and axial images, the contrast ratio was significantly higher in the SCI group than in the CCM group. Based on these results, a diagnostic scale was created. This scale made it possible to distinguish between SCI and CCM with approximately 90% accuracy.

MRI T2WI High Signal Is a Risk Factor for Perioperative Complications in Patients with Cervical Spondylosis with Spinal Cord Compression: A Propensity Matching Score Analysis

Objective

The purpose of this study was to compare the perioperative complications and clinical efficacy of patients with cervical spondylosis with spinal cord compression (CSWSCC) with or without MRI T2WIHS (T2-weighted image high signal) by means of propensity matching score grouping.

Methods

We analyzed a single-center data of 913 surgical patients with CSWSCC by propensity matching score in this study, of which 326 patients had preoperative cervical MRI T2WIHS. The patient's general condition and perioperative indicators were collected. The MRI T2WIHS and normal groups were paired 1 : 1 to eliminate selection bias by propensity matching score. Finally, a total of 312 pairs were matched successfully. The results of perioperative complications and other outcome variables were compared between the two groups by Cox function analysis.

Results

The postoperative blood loss, operation time, blood transfusion volume, systemic complications, local complications, volume of drainage, abnormal use of antibiotic, length of hospital stay, and JOA (Japanese Orthopaedic Association) improvement rate were analyzed. As the only complication with significant statistical difference, the incidence of IRI (ischemia-reperfusion injury) in patients with MRI T2WIHS was significantly higher. The length of hospital stay was more significantly increased in patients with MRI T2WIHS; on the contrary, the JOA improvement rate decreased significantly.

Conclusion

This study confirmed that there was no significant difference in the incidence of perioperative complications in CSWSCC patients with or without MRI T2WIHS, except for the IRI. Moreover, the JOA improvement rate of patients without MRI T2WIHS was significantly better, with the length of hospital stay reduced.

Preoperative T1 magnetic resonance imaging changes carry a poor postoperative prognosis in cervical myelopathy: A retrospective study of 182 patients

Background:

T2 scans are widely used to determine the prognosis for patients undergoing surgery for cervical myelopathy. In this study, we determined whether T1 MR changes in addition to T2 MR changes could have prognostic importance.

Methods:

This retrospective analysis involved 182 patients undergoing surgery for cervical myelopathy (2017–2020). There were 110 patients in Group 1 (only T2 MR changes) and 72 in Group 2 (both T1 and T2 MR changes). In addition, demographic, visual analog score (VAS), modified Japanese Orthopaedic Association (mJOA) scores, and operative details were recorded at 1 month, 3 months, 6 months, and 1 year postoperatively.

Results:

Notably, VAS scores were comparable at each point in time and were significantly better than the preoperative scores at 1 year postoperatively. Although mJOA scores were comparable at 1 month in both groups, they were better thereafter for Group 1 patients.

Conclusion:

The presence of T1 changes on the preoperative magnetic resonance imaging represented a poor prognostic indicator for the postoperative outcome compared to the presence of T2 changes alone.

Surgical outcome of laminoplasty for cervical spondylotic myelopathy: a single-institution experience

Background/aim

Cervical spondylotic myelopathy (CSM) develops as a result of compression of the spinal cord in the cervical region. Early diagnosis and surgical treatment can limit the progression of symptoms. Various surgical approaches and strategies have been described in the literature. This study aims to evaluate the clinical and radiological results of open-door laminoplasty for the treatment of CSM.

Materials and methods

In this study, we retrospectively analyzed the patients who underwent expansive open-door laminoplasty secured with titanium miniplates. Thirty-four patients with CSM who were followed up postoperatively for more than 12 months were included in the study. The modified Japanese Orthopaedic Association (mJOA) score was used to assess the degree of myelopathy. We evaluated cervical sagittal alignment with C2–C7 Cobb angle, the ambulatory status with the Nurick grade, and measured postoperative neck pain with the visual analogue scale (VAS).

Results

Themeanm JOA score was 11 (range 6–15) preoperatively, and 13.5 (range 9–16) postoperatively with an average 55% recovery rate (range 0–75) (p < 0.001). Themean–Nurick grade was 2 (range 1–3) preoperatively and 1 (range 0–3) postoperatively (p < 0.001). The median cervical lordotic angle increased from 7.5 ° preoperatively to 12.5 ° postoperatively (p = 0.044). K-line (+) patients› mean mJOA scores significantly increased from 10.8 ± 1.7 to 13.3 ± 1.7 postoperatively (p < 0.001). The mean preoperative VAS reduced from 2.66 ± 1.4 to 1.59 ± 1.4 postoperatively (p < 0.001).

Conclusion

Open-door laminoplasty technique is an effective surgical procedure that can be used safely to treat cervical spondylotic myelopathy. Our findings suggest that it can limit the progression of symptoms and alter the poor prognosis in CSM.

Anterior cervical microforaminotomy for persistent brachialgia in a patient with multilevel cervical spondylosis; comparing PROMIS with Nurick score for outcome of surgery

INTRODUCTION AND IMPORTANCE

The primal instinct of neurosurgeons has been to maintain spinal stability and motion since the beginning of spinal procedures. Conventional anterior approaches without fusion eliminate motion in time as fusion invariably sets in and hampers the vertebral column's normal dynamic physiology.

CASE PRESENTATION

We reported a 60 years old male patient who presented with signs of myelopathy, but his primary complaint was brachialgia. He had myelopathic features for eight years, for which he offered fusion surgery at multiple levels years ago, and he denied it. He was static since then, and the disease did not progress further. For intolerable pain, he agreed to minimally invasive surgery. Therefore, we operated for a right C6 transcorporeal microforaminotomy and removed the inciting disc material.

CLINICAL DISCUSSION

Clinical implication for anterior cervical microforaminotomy for this patient was successful where there was acute disc prolapse in cervical spondylotic myelopathy.

CONCLUSION

Finally, functional preservation of the cervical spine in multilevel spondylosis can optimize the fusion. In this case, the report authors have explored the comparison between the PROMIS score and the Nurick score, reporting for the first time.

Can Morphometric Analysis of Cervical Spondylotic Myelopathy Be a Tool for Surgical Outcome Prediction?

BACKGROUND

Cervical spondylotic myelopathy (CSM) is one of the leading causes of degenerative cervical myelopathy and the most common cause of spinal cord dysfunction in the elderly worldwide. Although there is emerging evidence that most patients improve after surgery, the key clinical and imaging factors predicting outcome remain uncertain. Our purpose is to evaluate preoperative and postoperative morphometric parameters on magnetic resonance imaging and their relation with neurological outcome at discharge and at 12-month follow-up.

METHODS

Morphometric features (volume, area, and antero-posterior diameter of the major stenotic section) were acquired by manual segmentation of the spinal canal using OsiriX open-source software and confronted with neurological outcome (at discharge and 12 months after surgery) using Nurick's scale.

RESULTS

Fifty-five patients (21 females and 34 males) with a mean age of 64.89 ± 11.95 years were analyzed. Recovery ratio was 2.44% ± 2.40% at discharge and 11.74% ± 2.50% at follow-up. Statistical analysis revealed a significant difference (P < .001) between Nurick's scale at admission versus discharge, at discharge versus follow-up at 1 year, and between admission and follow-up at 1 year. Morphometric changes (difference and ratio) between preoperative and postoperative measurements were also statistically significant (P < .001, paired samples t test). When linear regression was applied, volume difference was shown to have an influence on clinical improvement (P < .05; R = 0.519). Linear regression was also applied using recovery ratio at discharge and follow-up as dependent variables, with the same conclusion: volume difference between preoperative and postoperative measurements correlates with outcome improvement at 1 year after surgery.

CONCLUSIONS

Acquisition of morphometric features might be useful in predicting surgical outcome in patients with CSM. This information can be used to inform patients of their long-term postoperative prognosis in the future with more accurate and standardized measurements.

Degenerative cervical myelopathy

Degenerative cervical myelopathy (DCM) frequently leads to severe neurologic disability but is still frequently underdiagnosed. One explanation may be the variability of the symptoms presented by the patients, from paresthesia to quadriplegia, making it another great masquerader. What do we know? How can we manage better these patients? We will review the keys points concerning its challenging diagnosis (clinical and radiologic), some of the recent discoveries about DCM, notably the underlying genetic mutations identified, linked to its pathophysiology, before addressing the consensual points concerning its management and the major evolutive risk: acute decompensation.

Spondylotic and Other Structural Myelopathies

PURPOSE OF REVIEW

This article highlights both common structural causes of myelopathy, such as spondylotic disease, and infrequent but treatable causes, such as syringomyelia, spinal cord herniation, arachnoid cyst, arachnoid band and web, epidural lipomatosis, Hirayama disease, and arachnoiditis.

RECENT FINDINGS

Neuroimaging improvements and availability have uncovered many structural abnormalities in the spines and spinal cords of patients who were asymptomatic or minimally symptomatic. Recent published clinical series have improved our knowledge of the natural history of structural abnormalities and the risks of intervention versus conservative management.

SUMMARY

Myelopathy from a suspected structural cause is a common reason for neurologic consultation. Correlation between the history, examination, and imaging are especially important to determine whether intervention is necessary or conservative management is the best option.

Using a Combined Classification of Increased Signal Intensity on Magnetic Resonance Imaging (MRI) to Predict Surgical Outcome in Cervical Spondylotic Myelopathy

BACKGROUND The aim of this study was to verify whether the combined classification of increased signal intensity (ISI) on magnetic resonance imaging is more closely related to surgical outcomes than signal quality changes or signal longitudinal extent changes alone and to evaluate whether the combined classification ISI method could be used to predict surgical outcomes in cervical spondylotic myelopathy. MATERIAL AND METHODS Eighty-four patients (61 men and 23 women) who underwent surgery for cervical spondylotic myelopathy were included in this retrospective study. The patterns of ISI were classified into 3 categories based on (1) the quality of ISI into Grade 0: none, Grade 1: faint (fuzzy), and Grade 2: intense (sharp); (2) the longitudinal extent of ISI into none, focal, and multisegmental; and (3) the combined classification of the quality and longitudinal extent into Type 1 (none/none), Type 2 (focal/faint), Type 3 (focal/intense), Type 4 (multisegmental/faint), and Type 5 (multisegmental/intense). The multifactorial effects of variables were studied. A stepwise regression analysis was performed to verify whether this combined classification could predict outcome. RESULTS Of the 3 categories, the combined classification type of ISI was most closely related to recovery rate. Stepwise regression analysis confirmed the significance of combined classification of ISI as a predictor for surgical outcome. CONCLUSIONS A combined classification of ISI is more closely related to surgical outcomes than either signal quality changes or signal longitudinal extent changes alone and it could be used as a meaningful indicator for predicting surgical outcomes. We recommend further studies to confirm this finding.

DEGENERATIVE CERVICAL MYELOPATHY: A REVIEW OF CURRENT CONCEPTS

ABSTRACT Herbert von Luschka, a German anatomist, was the first to describe the developmental changes in the anatomical structures of the cervical spine. Degenerative cervical myelopathy (DCM) represents a collection of pathological entities that cause compression of the cervical spinal cord, resulting in a clinical syndrome typified by spasticity, hyperreflexia, pathologic reflexes, finger/hand clumsiness, gait disturbance and sphincter dysfunction. In the cervical spine, certain patients are more likely to have myelopathy due to a congenitally narrowed cervical spine canal. Degenerative changes are more common at C5 and C6 or C6 and C7 due to the increased motion at these levels. Additional contributors to canal narrowing are infolding of the ligamentum flavum, olisthesis, osteophytes, and facet hypertrophy. Myelopathy will develop in approximately 100% of patients with canal stenosis greater than 60% (less than 6 mm sagittal disc cord space). Classically it has an insidious onset, progressing in a stepwise manner with functional decline. Without treatment, patients may progress toward significant paralysis and loss of function. Treatment requires surgery with either anterior or posterior decompression of the area of narrowing, and probable fusion. Factors of a poor prognosis include symptoms lasting for more than 18 months, increased range of motion in the cervical spine, and female gender. In this study, we give an overview of the state-of-the-art in DCM, with a focus on the pathophysiology, clinical presentation, differential diagnosis, imaging evaluation, natural history, treatment options and complications. Level of evidence III; Review article.

Degenerative Cervical Myelopathy: Pathophysiology and Current Treatment Strategies

Chronic compression or ischemia of the spinal cord in the cervical spine causes a clinical syndrome known as cervical myelopathy. Recently, a new term “degenerative cervical myelopathy (DCM)” was introduced. DCM encompasses spondylosis, intervertebral disk herniation, facet arthrosis, ligamentous hypertrophy, calcification, and ossification. The pathophysiology of DCM includes structural and functional abnormalities of the spinal cord caused by static and dynamic factors. In nonoperative patients, cervical myelopathy has a poor prognosis. Surgical treatments, such as anterior or posterior decompression accompanying arthrodesis, arthroplasty, or laminoplasty, should be considered for patients with chronic progressive cervical myelopathy. Surgical decompression can prevent the progression of myelopathy and improve the neurologic status, functional outcomes, and quality of life, irrespective of differences in medical systems and sociocultural determinants of health. The anterior surgical approach to the cervical spine has the advantage of removing or floating the intervertebral disk, osteophytes, and ossification of the posterior longitudinal ligament that compress the spinal cord directly. The posterior surgical approach to the cervical spine is mainly used for multisegment spinal cord compression in patients with cervical lordosis. In this review article, we addressed the pathophysiology, clinical manifestations, differential diagnosis, and treatment options for DCM.

Magnetic resonance imaging and dynamic X-ray's correlations with dynamic electrophysiological findings in cervical spondylotic myelopathy: a retrospective cohort study

Background

Dynamic somatosensory evoked potentials (DSSEP) can be used to disclose abnormalities of ascending sensory pathways at dynamic positions and diagnose cervical spondylotic myelopathy (CSM). However, radiographic tests including magnetic resonance imaging (MRI) and dynamic X-ray are used much more widely in the management of CSM. Our study aims to clarify the correlations between several radiographic parameters and the DSSEP results, and further determine their reliability with clinical data.

Methods

We retrospectively enrolled 38 CSM patients with surgical intervention. DSSEP tests were performed before surgery. Amplitude ratios of DSSEP N13 and N20 waves at extension and flexion were calculated and recorded as N13_E, N20_E, N13_F, N20_F, respectively. Baseline severity was evaluated with the modified Japanese Orthopedic Association (mJOA) score and the Nurick grades. Prognosis was evaluated based on the 2-year recovery rate. Sagittal diameter and transverse areas of the cord and canal were measured and the the compressive ratios at the compressed site (Compression_Ratio), central (Central_Ratio), and 1/4-lateral points (1/4-Lateral_Compression_Ratio), and spinal cord/Canal Area Ratio were calculated. The intramedullary T2 hyperintensity patterns (Ax-CCM types) were also collected from MRI axial images. Dynamic X-rays were used to test for segmental instability of the cervical spine. The correlations between radiologic findings, DSSEP data, and clinical assessments were investigated.

Results

We found that DSSEP N13_E and N13_F correlated with the Compression_Ratio, Central_Ratio, 1/4-Lateral_Compression_Ratio (Pearson, p < 0.05) and Ax-CCM types (ANOVA, p < 0.05) in MRI axial images and cervical segmental instability in dynamic X-ray (t-test, p < 0.05). Apart from the 1/4-Lateral_Compression_Ratio, these radiographic parameters above also correlated with the baseline clinical assessments (Spearman or ANOVA or t-test, p < 0.05) and postoperative recovery rate (Pearson or ANOVA or t-test, p < 0.05).

Conclusions

We found that the preoperative Compression_Ratio, Central_Ratio and 1/4-Lateral_Compression_Ratio in MRI and cervical segmental instability in dynamic X-ray could reflect the dynamic neural dysfunction of the spinal cord. Different Ax-CCM types corresponded to different DSSEP results at extension and flexion, suggesting divergent pathophysiology. These radiographic parameters could help evaluate disease severity and predict postoperative prognosis.

Impact of cervical stenosis on multiple sclerosis lesion distribution in the spinal cord

OBJECTIVE

To determine whether demyelinating lesions attributable to multiple sclerosis (MS) occur more commonly in regions of pre-existing cervical stenosis (CS).

DESIGN/METHODS

One hundred comorbid MS/CS patients and 100 MS-only controls were identified via ICD codes and radiology reports from a retrospective chart review of the records of the University of Pennsylvania Hospital System (UPHS) from January 1^st, 2009 to December 31^st, 2018. For each patient, axial and sagittal T2 sequences of cervical MRI scans were examined. The cervical cord was split into 7 equal segments comprising the disc space and half of each adjacent vertebral body. Each segment was assessed for the presence of MS lesions and grade 2 CS or higher by previously published criteria. Lesions which were concerning for spondylotic-related signal change based on imaging characteristics were excluded (n=6, 3.2%). Clinical data was extracted from the electronic medical record.

RESULTS

Average age at the time of MRI was 57.0 +/- 10.5 years and average time with MS diagnosis was 15.3 +/- 9.2 years. The majority of patients had a diagnosis of relapse-remitting MS (81.0%) and the F:M ratio was 3.5. Eighty-five percent of patients were on treatment at the time of MRI, most often glatiramer acetate (35.0%). Spinal segments with at least grade 2 stenosis were significantly associated with the presence of an MS lesion in the same segment (χ² = 19.0, p < 0.001, OR = 2.6, 95% CI 1.8-3.7).

CONCLUSIONS

Our data suggest there is a significant association between segments of spinal cord with at least moderate CS and segments with MS lesions. Further analysis is required to assess if cervical stenosis is a causative or aggravating factor in multiple sclerosis.

Snake-Eye Myelopathy and Surgical Prognosis: Case Series and Systematic Literature Review

The prognostic value of "snake-eyes" sign in spinal cord magnetic resonance imaging (MRI) is unclear and the correlation with different pathological conditions has not been completely elucidated. In addition, its influence on surgical outcome has not been investigated in depth. A literature review according to PRISMA (Preferred reporting items for systematic review and meta-analysis protocols) guidelines on the prognostic significance of "snake-eyes" sign in operated patients was performed. Clinical, neuroradiological, and surgical data of three institutional patients, were also retrospectively collected. The three patients, with radiological evidence of "snake-eyes" myelopathy, underwent appropriate surgical treatment for their condition, with no new post-operative neurological deficits and good outcome at follow-up. The literature review, however, reported conflicting results: the presence of "snake-eyes" sign seems a poor prognostic factor in degenerative cervical myelopathy, even if some cases can improve after surgery. "Snake-eyes" myelopathy represents a rare form of myelopathy; pathophysiology is still unclear. The frequency of this myelopathy may be greater than previously thought and according to our literature review it is mostly a negative prognostic factor. However, from our experience, prognosis might not be so dire, especially when tailored surgical intervention is performed; therefore, surgery should always be considered and based on the complete clinical, neurophysiological, and radiological data.

Postoperative Resolution of MR T2 Increased Signal Intensity in Cervical Spondylotic Myelopathy: The Impact of Signal Change Resolution on the Outcomes

STUDY DESIGN

A prospective comparative imaging study.

OBJECTIVE

This study investigated whether postoperative resolution of spinal cord increased signal intensity (ISI) reflected symptom improvement and surgical outcomes in cervical spondylotic myelopathy (CSM) patients.

SUMMARY OF BACKGROUND DATA

Although some CSM patients exhibit magnetic resonance imaging (MRI) ISI, its alteration and resolution have not been investigated. The association between postoperative ISI resolution and surgical outcomes in CSM patients remains controversial.

METHODS

A total of 505 consecutive CSM patients (311 males; 194 females) aged a mean of 66.6 years (range, 41-91) were enrolled. All were treated with laminoplasty and underwent MRI scans preoperatively and after an average of 26.5 months postoperatively (range 12-66 months). ISI was classified pre- and postoperatively based on sagittal T2-weighted magnetic resonance images into Grade 0, none; Grade 1, light (obscure); and Grade 2, intense (bright). The patients' pre- and postoperative neurological statuses were evaluated using the Japanese Orthopedic Association scoring system for cervical myelopathy [Japanese Orthopedic Association (JOA) score] and other quantifiable tests, including the 10-s grip and release (10-s G&R) test and 10-s step test.

RESULTS

A total of 337 patients showed preoperative ISI. Among these, 42 (12.5%) showed postoperative ISI resolution, associated with better postoperative JOA score and recovery rate, 10-s G&R and 10-s step test scores than those who retained it. Patients with preoperative Grade 2 ISI had no postoperative ISI resolution. Patients with ISI improvement from Grade 1 to Grade 0 had better outcomes than those with ISI worsening from Grade 1 to Grade 2.

CONCLUSION

Postoperative ISI resolution in CSM patients reflects postoperative symptoms and surgical outcomes. Patients who exhibit ISI resolution have better clinical outcomes.

LEVEL OF EVIDENCE

3.

Cervical Spondylotic Myelopathy: Natural Course and the Value of Diagnostic Techniques -WFNS Spine Committee Recommendations

Objective

This study presents the results of a systematic literature review conducted to determine most up-to-date information on the natural outcome of cervical spondylotic myelopathy (CSM) and the most reliable diagnostic techniques.

Methods

A literature search was performed for articles published during the last 10 years.

Results

The natural course of patients with cervical stenosis and signs of myelopathy is quite variable. In patients with no symptoms, but significant stenosis, the risk of developing myelopathy with cervical stenosis is approximately 3% per year. Myelopathic signs are useful for the clinical diagnosis of CSM. However, they are not highly sensitive and may be absent in approximately one-fifth of patients with myelopathy. The electrophysiological tests to be used in CSM patients are motor evoked potential (MEP), spinal cord evoked potential, somatosensory evoked potential, and electromyography (EMG). The differential diagnosis of CSM from other neurological conditions can be accomplished by those tests. MEP and EMG monitoring are useful to reduce C5 root palsy during CSM surgery. Notable spinal cord T2 hyperintensity on cervical magnetic resonance imaging (MRI) is correlated with a worse outcome, whereas lighter signal changes may predict better outcomes. T1 hypointensity should be considered a sign of more advanced disease.

Conclusion

The natural course of CSM is quite variable. Signal changes on MRI and some electrophysiological tests are valuable adjuncts to diagnosis.

Is microdiffusion imaging able to improve the detection of cervical myelopathy? Study protocol of a prospective observational trial (MIDICAM-Trial)

INTRODUCTION

The diagnosis of degenerative cervical myelopathy (DCM) is difficult in numerous patients due to the limited correlation of clinical symptoms, electrophysiology and MRI. This applies especially for early disease stages with mild symptoms or in uncertainty due to comorbidities. Conventional MRI myelopathy signs show a restricted sensitivity to clinical symptoms of at most 60%. It is desirable to select patients for surgical treatment as early as possible before irreversible neurological damage occurs. To improve treatment, a more reliable imaging is necessary. Microdiffusion imaging (MIDI) is an innovative MRI modality to depict tissue alterations within one voxel based on diffusion-weighted imaging (DWI) postprocessing. By separating the affected area into several mesoscopic compartments, pathological changes might be detected more sensitive through this subtle tissue resolution. We hypothesise, that MIDI shows myelopathic alterations more sensitive than conventional MRI and improves the correlation to functional impairment.

METHODS AND ANALYSIS

In this prospective, observational trial, 130 patients with a relevant degenerative cervical spinal stenosis receive MRI including MIDI and a standard clinical and electrophysiological assessment. Special subvoxel diffusion parameters are calculated. Clinical follow-ups are conducted after 3, 6 and with additional MRI and electrophysiology after 12 months. The primary endpoint is the sensitivity of MIDI to detect functional myelopathy defined by clinical and electrophysiological features correlated to conventional MRI myelopathy signs. Twenty healthy subjects will be included as negative control. The results will provide new insights into the development of mesoscopic spinal cord alterations in DCM associated to the clinical course. Aim is to improve the diagnostics of incipient myelopathy through this new modality.

ETHICS AND DISSEMINATION

The study protocol is approved by the Ethics Committee of the University of Freiburg (reference 261/17). The results will be published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

DRKS00012962.

Recent advances in the management of cervical spondylotic myelopathy: bibliometric analysis and surgical perspectives

OBJECTIVE

Cervical spondylotic myelopathy (CSM) has become a prevalent cause of spinal cord dysfunction among the aging population worldwide. Although great strides have been made in spine surgery in past decades, the optimal timing and surgical strategy to treat CSM have remained controversial. In this article the authors aimed to analyze the current trends in studies of CSM and to summarize the recent advances of surgical techniques in its treatment.

METHODS

The PubMed database was searched using the keywords pertaining to CSM in human studies that were published between 1975 and 2018. Analyses of both the bibliometrics and contents, including the types of papers, authors, affiliations and countries, number of patients, and the surgical approaches were conducted. A systematic review of the literature was also performed with emphasis on the diagnosis and treatment of mild CSM.

RESULTS

A total of 1008 papers published during the span of 44 years were analyzed. These CSM studies mainly focused on the natural history, diagnosis, and treatment, and only a few prospective randomized trials were reported. For the authors and affiliations, there was a shift of clustering of papers toward Asian countries in the past decades. Regarding the treatment for CSM, there was an exponential growth of surgical series published, and there was a trend toward slightly more anterior than posterior approaches through the past decade. Patients with CSM had increased risks of neurological deterioration or spinal cord injury with nonoperative management. Because surgery might reduce the risks, and early surgery was likely to be correlated with better outcomes, there was a trend toward attention to mildly symptomatic CSM.

CONCLUSIONS

There is emerging enthusiasm for research on CSM worldwide, with more publications originating in Asian countries over the past few decades. The surgical management of CSM is evolving continuously toward early and anterior approaches. More prospective investigations on the optimal timing and choices of surgery are therefore needed.

Surgical approaches and outcomes for cervical myelopathy with increased signal intensity on T2-weighted MRI: a meta-analysis

OBJECTIVE

Increased signal intensity (ISI) on T2-weighted magnetic resonance imaging (MRI) often indicates severe compression in patients with cervical myelopathy (CM). The optimal surgical approach for CM patients with ISI on T2-weighted MRI remains unclear. This meta-analysis aims to compare the clinical outcomes between anterior and posterior approaches for the treatment of these patients.

METHODS

MEDLINE, EMBASE, Web of Science, and Chinese National Knowledge Infrastructure (CNKI) were searched for relevant studies through January 2019. Statistical comparisons were made when appropriate.

RESULTS

A total of 9 studies (748 participants) out of 1066 citations were included in this study. All of the selected studies were high quality, as indicated by the Newcastle-Ottawa scale and the Cochrane Collaboration tool for assessing the risk of bias. Clinical outcomes were compared between anterior and posterior approaches in 4 studies (237 participants). The preoperative Japanese Orthopedic Association (JOA) score was similar between the two groups [P = 0.98, weighted mean difference (WMD) = 0.01 (- 0.58, 0.59)]. The postoperative JOA score [P < 0.05, WMD = 0.68 (0.06, 1.30)] and recovery rates [P < 0.01, WMD = 0.12 (0.06, 0.17)] were significantly higher in the anterior group than in the posterior group.

CONCLUSION

The anterior approach was associated with better postoperative neural function than the posterior approach in CM patients with ISI on T2-weighted MRI.

The relationship between preoperative factors and the presence of intramedullary increased signal intensity on T2-weighted magnetic resonance imaging in patients with cervical spondylotic myelopathy

OBJECTIVE

To investigate preoperative factors affecting the presence of intramedullary increased signal intensity (ISI) on T2-weighted magnetic resonance imaging (MRI) in patients with cervical spondylotic myelopathy (CSM) and the impact of ISI on clinical manifestations.

PATIENTS AND METHODS

Eighty-nine patients with CSM were retrospectively reviewed from January 2013 to December 2016 in our hospital. Based on the presence or absence of ISI on axial and sagittal T2-weighted MRI, patients were divided into ISI group (48 cases) and non-ISI group (41 cases). Factors such as age, sex, body mass index (BMI), duration of symptoms, clinical symptoms and signs, number and distribution of spinal cord compression levels, preoperative Japanese Orthopedic Association (JOA) score, preoperative C2-C7 lordotic angle, preoperative C2-C7 range of motion (ROM), maximal canal compromise (MCC) and maximal spinal cord compression (MSCC) were initially compared using univariate analysis. Factors with significant result in univariate analysis were included in multivariate logistic regression analysis. Receiver operating characteristic (ROC) curve and the area under the curve (AUC) were applied to evaluate the reliability of multivariate logistic regression model.

RESULTS

Univariate analysis showed that the number of spinal cord compression levels, preoperative JOA score, MCC and MSCC might be related to the presence of ISI (P <  0.05). Furthermore, multivariate logistic regression analysis revealed that the number of spinal cord compression levels (OR = 0.203, P <  0.05), preoperative JOA score (OR = 4.274, P <  0.05) and MSCC (OR = 0.250, P <  0.05) were independent preoperative risk factors associated with the presence of ISI, yielding an AUC of 0.9558. Patients with ISI showed a trend of increasing clinical symptoms and signs, and also exhibited statistically significantly increased frequencies of clumsy hands, lower limb spasticity, impairment of gait, broad-based, unstable gait, weakness and motor deficits (P <  0.05).

CONCLUSION

Multilevel spinal cord compression, lower preoperative JOA score and greater MSCC are independent preoperative risk factors related to the presence of ISI on T2-weighted MRI in patients with CSM. Patients with ISI tend to have more clinical symptoms and signs, especially in lower limb manifestations and motor deficits.

Predictors for Development of Symptomatic Myelopathy in Patients with Radiculopathy Caused by Cervical Ossification of Posterior Longitudinal Ligament

OBJECTIVE

To identify clinical factors predicting the development of myelopathy in cervical ossification of the posterior longitudinal ligament (OPLL) patients with radiculopathy.

METHODS

We retrospectively reviewed 83 cervical OPLL patients who presented with radiculopathy. On the basis of the symptoms and physical findings, we divided patients into 2 groups: myelopathy group and nonmyelopathy group. Demographic, clinical, and radiologic characteristics were reviewed and analyzed among the 2 groups. Predictors for the development of myelopathy were assessed via univariate and multivariate analysis.

RESULTS

Univariate analysis demonstrated that a high occupying ratio and the presence of an intramedullary high signal were risk factors for development of myelopathy from radiculopathy in OPLL patients. Multivariate analysis further identified that a high occupying ratio was the only independent predictor (odds ratio 1.05, 95% confidence interval 1.003-1.091, P = 0.035). The cervical range of motion and minor trauma were not related to the development of myelopathy in our study.

CONCLUSIONS

Nonmyelopathic OPLL patients with radiculopathy and a high occupying ratio were at higher risk of developing myelopathy, and surgical intervention should be recommended in these cases. However, for elderly patients with significant comorbid conditions, the risks and benefits of surgery should be carefully considered.

Snake-Eyes Appearance on MRI Occurs during the Late Stage of Hirayama Disease and Indicates Poor Prognosis

Purpose

Because Hirayama disease is stereotyped as a self-limited disease in the absence of a definite pathology, we investigated the potential relationship between snake-eyes appearance (SEA) and Hirayama disease to bring a new perspective in the pathological process of Hirayama disease based on relevant radiological and clinical evidence.

Methods

A total of 30 cases observed SEA were selected from 293 patients with Hirayama disease to constitute the SEA group, and an equal number of cases were randomly selected from the remaining patients to form the non-SEA group. Cervical magnetic resonance imaging (MRI) was performed and subsequently used to measure the anteroposterior diameter and anterior shifting of the spinal cord. Additionally, clinical data, such as age, sex, duration of symptoms, symptoms, and signs, were collected and analyzed.

Results

Of 293 patients, 10.6% appeared with the SEA, which was mainly multisegmental (86.7%), particularly at the C5-6 segment (73.3%), and intense with a well-defined border (70.0%). The SEA group was an older population (p < 0.0001) with a longer duration (p < 0.0001) and a higher incidence of Hoffmann signs and knee hyperreflexia (p < 0.0001, p = 0.0038, respectively). The degree of spinal cord atrophy demonstrated a close association with the SEA, as it was significantly worse in the SEA group and SEA segment (p = 0.0008, p < 0.0001, respectively). The degree of spinal cord atrophy was positively related to both age and duration (p = 0.0095, p = 0.0176, respectively).

Conclusions

Confirmed as an irreversible lesion and an indication of poor prognosis, SEA appears during the late stage of Hirayama disease and is closely related to pyramidal signs and spinal cord atrophy.

The Relation between Cord Signal and Clinical Outcome after Anterior Cervical Discectomy in Patients with Degenerative Cervical Disc Herniation

Introduction

Cervical spondylotic myelopathy is a cervical cord compressive lesion that occurs as a result of the normal degenerative process which may cause magnetic resonance imaging (MRI) cord intensity changes that may worsen the clinical outcome even after successful anterior cervical decompression.

Objective

To assess the relation between MRI T2 Weighted images (T2 WI) hyperintense cord signal and clinical outcome after anterior cervical discectomy in patients with degenerative cervical disc herniation.

Materials and Methods

This is a retrospective observational study that was conducted on twenty-five patients with degenerative cervical disc prolapse associated with MRI T2WI hyperintense cord signal, at the Department of Neurosurgery, Qena University Hospital, South Valley University from August 2014 to December 2016. A complete clinical and radiological evaluation of the patients was done. Anterior cervical discectomy and fusion was done for all patients. Patients were clinically assessed preoperatively and postoperatively at 3, 6, and 12 months using Modified Japanese Orthopedic Association (MJOA) score. Radiographic assessment was done by preoperative and postoperative T2WI MRI. The statistical analysis was done using Statistical Package for the Social Sciences (SPSS) software (version 22.0).

Results

There were 25 patients included in the study; 16 (64%) females and 9 (36%) males. The mean age was 46.89 ± 7.52 standard deviation (SD) years with range from 26 to 64 years, 3 (12%) patients had worsened in the form of postoperative motor power deterioration, and 14 (56%) patients has no improvement and remain as preoperative condition. The remaining 8 (32%) patients had a reported postoperative improvement of symptoms and signs according to MJOA score. The mean follow-up period (in months) was 11 ± 2.34 (SD).

Conclusion

The presence of T2W hyperintense signal on preoperative MRI predicts a poor surgical outcome in patients with cervical disc prolapse. The regression of T2W ISI postoperatively correlates with better functional outcomes.

Efficacy of diffusion tensor imaging in identification of degenerative cervical spondylotic myelopathy

Aim and objectives

To study the diagnostic accuracy of Diffusion tensor imaging technique in detection of cervical spondylotic myelopathy changes.

Material and method

Study population included 50 patients with symptoms of cervical myelopathy. The patients were evaluated based on symptoms using the European myelopathy scoring system and were divided into: Grade 1, including patients with mild symptoms; Grade 2, referring to patients with moderate symptoms and Grade 3, which included patients revealing severe symptoms. All the patients were investigated with a 1.5 T MRI unit acquiring DWI and DTI sequences. FA and ADC values from each spinal segment were analyzed in terms of Frequency, Percentage, Mean, Standard Deviation and Confidence Intervals. The comparison of values was done by ANOVA and post hoc analysis by bonferroni test. Comparison of accuracy of FA, ADC and T2WI in recognizing myelopathic changes was done by t-test. Receiver Operating Characteristics (ROC) analysis was performed to obtain a cut off value of FA and ADC for each spinal level to identify myelopathic change in the spinal cord.

Results

The study revealed a significant difference in the mean FA and ADC value of stenotic and Non-stenotic segments. T2WI was highly significant (p = 0.000) in recognizing myelopathy changes in patients falling under Grade 2(moderate) and Grade 3(severe) according to European Myelopathy scoring system. Regarding patients under Grade 1 (mild) FA and ADC values showed significant difference compared to T2WI. The collective sensitivity in the identification of myelopathic changes was highest with FA (79%) as compared to ADC (71%) and T2WI (50%). ROC analysis was done to determine the cut off values of FA and ADC at each cervical spine segments. The proposed cut off, for FA and ADC at the level of C1–C2 is 0.68 and 0.92, C2–C3 is 0.65 and 1.03, C3–C4 is 0.63 and 1.01, C4–C5 0.61 and 0.98, At C5–C6 0.57 and 1.04, At C6–C7 0.56 and 0.96 respectively.

Conclusion

FA and ADC values enhance the efficacy and accuracy of MRI in the diagnosis of cervical spondylotic myelopathy. Hence diffusion tensor imaging can be used as a non-invasive modality to recognize spondylotic myelopathy changes even in the early stages, which can be helpful in deciding on appropriate timing of decompression surgery before the irreversible chronic changes set in.

Alterations in Intramedullary T2-weighted Increased Signal Intensity following Laminoplasty in Cervical Spondylotic Myelopathy Patients: Comparison Between Pre- and Postoperative Magnetic Resonance Images

STUDY DESIGN

A prospective comparative imaging study.

OBJECTIVE

This study investigated whether the postoperative classification of and alterations in increased signal intensity (ISI) of the spinal cord reflected the postoperative severity of symptoms and surgical outcomes in cervical spondylotic myelopathy (CSM) patients.

SUMMARY OF BACKGROUND DATA

Although ISI on performing magnetic resonance imaging (MRI) is observed in CSM patients, alterations in ISI have not been investigated. The association of postoperative ISI with surgical outcomes in CSM patients remains controversial.

METHODS

Totally, 505 consecutive CSM patients (311 males) with a mean age of 66.6 (range, 41-91) years were enrolled. All were treated with laminoplasty and underwent MRI scans: preoperatively and after an average of 26.5 months postoperatively (range 12-66 months). ISI was classified pre- and postoperatively into three groups based on sagittal T2-weighted magnetic resonance images: Grade 0, none; Grade 1, light (obscure); and Grade 2, intense (bright). The patients' pre- and postoperative neurological statuses were evaluated using the Japanese Orthopaedic Association scoring system for cervical myelopathy (JOA score) and other quantifiable tests, including the 10-s grip and release (10-s G&R) test and 10-s step test.

RESULTS

Preoperatively, 168 patients had Grade 0 ISI, 169 had Grade 1, and 168 had Grade 2; postoperatively, 210 patients had Grade 0 ISI, 94 had Grade 1, and 201 had Grade 2. Patients with postoperative Grade 0 ISI had a better postoperative JOA score, recovery rate, and 10-s G&R and 10-s step test scores than those with other grades. The postoperative ISI grade improved in 66 patients (13.1%), worsened in 57 (11.3%), and remained unchanged in 382 (75.6%).

CONCLUSION

Postoperative ISI partially reflects postoperative symptoms and surgical outcomes. Alterations in ISI were observed postoperatively in 123 patients (24.4%) and were not correlated with surgical outcomes.

LEVEL OF EVIDENCE

2.

Cervical spondylotic myelopathy patients with prior cerebral infarction: Clinical characteristics, surgical outcomes and prognostic value of "prior cerebral infarction"

OBJECTIVE

To investigate the clinical characteristics and surgical outcomes of patients with cervical spondylotic myelopathy (CSM) and prior cerebral infarction (CI); to identify whether "prior CI" correlates with poor surgical outcomes.

PATIENTS AND METHODS

Twenty-two patients with CSM and prior CI were retrospectively reviewed and included as the CI group while 100 CSM patients without CI were included as the control group (matched for gender, age, symptom duration and surgical approach). Extensive demographic and surgery-related data for patients in both groups were collected and compared. Multivariate logistic regression analysis was performed to assess all potential factors affecting surgical outcomes.

RESULTS

Compared to the control group, the CI group had the following: significantly higher percentages of hypertension, "progressive myelopathy", "rapid progressive myelopathy" and "intramedullary T2-weighted hyperintensity on MRI"; lower mean "preoperative mJOA score" and "postoperative mJOA score"; higher percentages of "preoperative mJOA score ≤11″ and "recovery rate of mJOA score <50%". In the CI group, 14 patients had CI within 6 months before CSM, and their percentage of "rapid progressive myelopathy" was higher than that of patients who had CI over 6 months before CSM. Logistic regression analysis showed that smoking, "symptom duration ≥12 months", "T2-weighted hyperintensity" and "prior CI" correlated with poor surgical outcome.

CONCLUSION

Rapid progressive myelopathy with advanced neurological impairment and "intramedullary T2-weighted hyperintensity" are common in patients with CSM and prior CI. Surgical outcomes in these patients are poorer than those of ordinary CSM patients. "Prior CI" is a risk factor for predicting poor surgical outcomes.

Clinico-Radiographic Discordance: An Evidence-Based Commentary on the Management of Degenerative Cervical Spinal Cord Compression in the Absence of Symptoms or With Only Mild Symptoms of Myelopathy

STUDY DESIGN

Narrative review with commentary.

OBJECTIVES

The growing use of magnetic resonance imaging (MRI) often leaves clinicians faced with scenarios where imaging findings are inconsistent with the clinical picture. This is particularly relevant for degenerative cervical spinal cord compression (CSCC). In this article, we provide a focused narrative literature review to address whether (1) surgery should be offered to asymptomatic patients with CSCC and (2) should MRI spinal cord signal changes influence clinical decisions for a patient with mild myelopathy from CSCC?

METHODS

Illustrative cases are presented with expert commentary which is supplemented by a focused literature review.

RESULTS

The literature suggests that CSCC from degenerative pathology is a common incidental radiographic finding. For those without symptoms of myelopathy, the short-term risk of progression is low. There is a lack of evidence to support surgery for asymptomatic individuals with CSCC who have no risk factors for progression. For these patients, the authors suggest non-operative management that includes education on the symptoms of myelopathy, clinical follow-up within 6 to 12 months, and avoidance of high-risk activities. Conversely, symptomatic patients have a notable risk of progression. Surgical intervention improves neurological function and quality of life regardless of severity. The authors support surgery as an option for all patients with mild myelopathy who are appropriate operative candidates. Intramedullary signal change on MRI has not been shown to reliably predict progression.

CONCLUSIONS

While MRI technologies are under evolution, we advise that surgical decisions for patients with CSCC should rely on clinical assessment and not imaging findings.

Clinico-Radiological Outcome Analysis in Craniovertebral Junction Diseases: An Institutional Experience of 38 Patients in a Tertiary Care Centre

BACKGROUND

Craniovertebral junction diseases, although considered rare, are common in northern parts of India. This study was conducted to evaluate the clinico-radiologic and surgical outcome of patients with a minimum follow-up of 1 year. Our study also compared bony fusion among various techniques of posterior fusion.

METHODS

This retrospective study was performed with 38 patients who met the inclusion criteria for analysis. These patients were contacted by telephone and letters, and their clinical examination and radiologic investigations were performed at a follow-up visit. The preoperative, postoperative, and follow-up clinical evaluations of the patients were done using the Nurick grading system.

RESULTS

The age range was 4-60 years with an average of 20.5 years. There were 31 male and 7 female patients, with a male:female ratio of 4.43:1. There were 13 cases of fixed atlantoaxial dislocation (AAD), 17 cases of mobile AAD, 6 cases of traumatic AAD, and 2 cases of postinfective AAD. The majority of these patients (n = 29; 76.31%) had neck pain and cerebellovestibular disturbances (n = 27; 71.1%). Sphincter disturbances were observed in 9 patients. An increase in craniovertebral angle was observed in postoperative period in all patients. Initially, 84% of the patients had a poor Nurick grade; this was reduced to 28% after the surgical intervention. One hundred percent bony fusion was attained in patients who underwent rigid fixation technique, and 80% was attained using a semirigid fixation technique.

CONCLUSIONS

The key to successful management of craniovertebral junction disease is individualized selection of judicious surgical intervention from various available techniques.

Postoperative Resolution of Magnetic Resonance Imaging Signal Intensity Changes and the Associated Impact on Outcomes in Degenerative Cervical Myelopathy: Analysis of a Global Cohort of Patients

STUDY DESIGN

Subanalysis of the prospective AOSpine CSM North America and International studies.

OBJECTIVE

To describe the postoperative changes in magnetic resonance imaging (MRI) spinal cord signal intensity in degenerative cervical myelopathy (DCM) patients and to investigate the impact of its postoperative resolution on clinical outcomes.

SUMMARY OF BACKGROUND DATA

When examining the spinal cord, hyperintensity found in MRI T2-weighted images and hypointensity in T1-weighted images are known to correlate with preoperative severity of DCM and to predict postoperative neurological recovery. However, the clinical importance of these signal intensity changes in postoperative images has not been established.

METHODS

Among 757 surgical DCM patients enrolled in two prospective multicenter studies, postoperative MRI images obtained between 6 and 24 months after the operation were examined with a focus on T2 hyper- and T1 hypointensity in the spinal cord. The 2-year postoperative Nurick grade, modified Japanese Orthopaedic Association score and modified Japanese Orthopaedic Association recovery rate (RR) were analyzed between patients with or without resolution of signal intensity changes.

RESULTS

A total of 167 patients with preoperative T2 hyperintensity were included with complete postoperative MRI images. Of these patients, 11% showed resolution of signal intensity changes, 70% retained T2 hyperintensity only, and 19% showed both T2 hyper- and T1 hypointensity postoperatively. There was a stepwise trend toward worse postoperative outcomes, with the no signal intensity change group showing the best outcome and the T1 hypointensity group showing the worst (mean RR: 72% vs. 51% vs. 36%, P = 0.02). Patients who exhibited resolution of T2 hyperintensity showed better outcomes than those who retained it (RR: 72% vs. 47%, P = 0.04), but the resolution of T1 hypointensity was not associated with improved outcomes (RR: 38% vs. 26%, P = 0.36).

CONCLUSION

Postoperative resolution of T2 hyperintensity in patients with DCM was associated with the best clinical outcomes, whereas those with T1 hypointensity showed the worst.

LEVEL OF EVIDENCE

3.

Spinal cord MRI signal changes at 1 year after cervical decompression surgery is useful for predicting midterm clinical outcome: an observational study using propensity scores

BACKGROUND CONTEXT

There is little information on the relationship between magnetic resonance imaging (MRI) T2-weighted high signal change (T2HSC) in the spinal cord and surgical outcome for cervical myelopathy. We therefore examined whether T2HSC regression at 1 year postoperatively reflected a 5-year prognosis after adjustment using propensity scores for potential confounding variables, which have been a disadvantage of earlier observational studies.

PURPOSE

The objective of this study was to clarify the usefulness of MRI signal changes for the prediction of midterm surgical outcome in patients with cervical myelopathy.

STUDY DESIGN/SETTING

This is a retrospective cohort study.

PATIENT SAMPLE

We recruited 137 patients with cervical myelopathy who had undergone surgery between 2007 and 2012 at a median age of 69 years (range: 39-87 years).

OUTCOME MEASURES

The outcome measures were the recovery rates of the Japanese Orthopaedic Association (JOA) scores and the visual analog scale (VAS) scores for complaints at several body regions.

MATERIALS AND METHODS

The subjects were divided according to the spinal MRI results at 1 year post surgery into the MRI regression group (Reg+ group, 37 cases) with fading of T2HSC, or the non-regression group (Reg- group, 100 cases) with either no change or an enlargement of T2HSC. The recovery rates of JOA scores from 1 to 5 years postoperatively along with the 5-year postoperative VAS scores were compared between the groups using t test. Outcome scores were adjusted for age, sex, diagnosis, symptom duration, and preoperative JOA score by the inverse probability weighting method using propensity scores.

RESULTS

The mean recovery rates in the Reg- group were 35.1%, 34.6%, 27.6%, 28.0%, and 30.1% from 1 to 5 years post surgery, respectively, whereas those in the Reg+ group were 52.0%, 52.0%, 51.1%, 49.0%, and 50.1%, respectively. The recovery rates in the Reg+ group were significantly higher at all observation points. At 5 years postoperatively, the VAS score for pain or numbnessin the arms or hands of the patients in the Reg+ group (24.7 mm) was significantly milder than that of the patients in the Reg- group (42.2 mm).

CONCLUSIONS

Spinal T2HSC improvement at 1 year postoperatively may predict a favorable recovery until up to 5 years after surgery.

High field structural MRI in the management of degenerative cervical myelopathy

Introduction: This is a narrative overview of the pathophysiology, investigation and management of Degenerative Cervical Myelopathy (DCM). This review article also takes a look ahead to the impact high resolution MRI may have on treatment.Background: DCM is the most common cause of spinal dysfunction and yet it remains poorly understood. It is becoming increasingly common in our ageing population. Disc and facet joint abnormalities, osteophytes, spondylothisthesis and ligamentous hypertrophy all act together to produce spinal canal and neuronal foramina stenosis which in turn causes neural compromise. Its impact on the quality of life of this patient group and the wider economy is vast. Some patients with overt cord compression and MRI signal change in their cervical cord may only have subtle clinical signs whilst others with less striking imaging may be profoundly myelopathic. Who to operate on and when remains a neurosurgical dilemma in this group of patients.Methods: A number of articles with a broad variation in methodology were reviewed and referenced during the production of this paper.Results: This paper is a narrative review. The results presented in all the referenced articles were considered.Conclusion: The process of developing new imaging techniques will give a greater understanding of the causes of the symptoms of DCM and in a wider context facilitate further surgical and medical strategies that are more cost effective and beneficial to patients. The advent of 7T MRI or further optimisation of safer 3T MRI sequences may soon provide this opportunity and the diagnostic gap in spinal cord imaging can begin to close.

Degenerative Cervical Myelopathy: A Clinical Review

Degenerative Cervical Myelopathy (DCM) is the most common form of spinal cord impairment in adults and results in disability and reduced quality of life. DCM can present with a wide set of clinical and imaging findings, including: 1) pain and reduced range of motion of the neck, and motor and sensory deficits on clinical exam, and 2) cord compression due to static and dynamic injury mechanisms resulting from degenerative changes of the bone, ligaments, and intervertebral discs on MRI. The incidence and prevalence of DCM has been estimated at a minimum of 4.1 and 60.5 per 100,000, respectively, but surgical trends and an aging population suggest these numbers will rise in the future. The diagnosis of DCM is based on clinical examination, with a positive Hoffmann's sign and hand numbness typically appearing in the upper limbs, and gait abnormalities such as difficulty with tandem gait serving as sensitive diagnostic findings. Loss of bladder function may also occur in patients with severe DCM. The degree of neurological impairment can be measured using the modified Japanese Association Scale (mJOA) or Nurick grade. Non-operative management has a limited role in the treatment, while surgical management has been shown to both be safe and effective for halting disease progression and improving neurological function. Predictors of surgical outcome include age and baseline severity, indicating that early recognition of DCM is important for ensuring an optimal surgical outcome.