Increased Signal Intensity Grade Research Articles

Impact of congenital spinal stenosis on the outcome of three-level anterior cervical discectomy and fusion in patients with cervical spondylotic myelopathy: a retrospective study.

To investigate whether congenital cervical spinal stenosis (CCSS) affects the outcome of three-level anterior cervical discectomy and fusion (ACDF) in patients with cervical spondylotic myelopathy (CSM). One hundred seventeen patients with CSM who underwent three-level ACDF between January 2019 and January 2023 were retrospectively examined. Patients were grouped according to presence of CCSS, which was defined as Pavlov ratio ≤ 0.75. The CCSS and no CCSS groups comprised 68 (58.1%) and 49 (41.9%) patients, respectively. The Japanese Orthopaedic Association (JOA) score did not significantly differ between the two groups at any postoperative time point (p > 0.05). The JOA improvement rate was lower in the CCSS group 1 month after surgery (41.7% vs. 45.5%, p < 0.05), but showed no difference at any follow-up time point after one month. Multivariate logistic regression identified preoperative age (OR = 10.639), JOA score (OR = 0.370), increased signal intensity (ISI) in the spinal cord on T2-weighted MRI (T2-WI) (Grade 1: OR = 6.135; Grade 2: OR = 29.892), and degree of spinal cord compression (30-60%: OR = 17.919; ≥60%: OR = 46.624) as independent predictors of a poor oneyear outcome (JOA recovery rate < 50%). Although early JOA improvement is slower in the CCSS group, it does not affect the final neurological improvement at 1 year. Therefore, CCSS should not be considered a contraindication for three-level ACDF in patients with CSM. The main factors influencing oneyear outcome were preoperative age, JOA score, ISI grade, and degree of spinal cord compression.

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.

Increased signal intensity of spinal cord on T2W magnetic resonance imaging for cervical spondylotic myelopathy patients: Risk factors and prognosis (a STROBE-compliant article).

To investigate the risk factors for progression of increased signal intensity (ISI) on T2W magnetic resonance imaging (MRI) and its prognostic value in patients with cervical spondylotic myelopathy (CSM).A total of 109 patients with CSM were included in this study. All the patients were treated with anterior cervical discectomy and fusion. MRI was performed for all 109 patients preoperatively and at the final follow-up. Radiological evaluation included ISI, anterior compression (AC) of dural and spinal cord, hyperintensity region (HR) at the involved level. Clinical data including Japanese Orthopedic Association (JOA) score, Neck Disability Index (NDI) score, and Visual Analogue Scale were collected and evaluated. Patients were divided into 2 groups according to ISI grades (Group A: no hyper-intensity; Group B: presence of ISI). Then all patients presented with ISI were divided into 2 subgroups based on the range of HR (Group B1: hyper-intensity diameter accounts for less than half of the spinal cord diameter at the involved level; Group B2, hyper-intensity diameter accounts for more than half of the spinal cord diameter at the involved level). AC, disease duration, age, and gender were analyzed as potential risk factors.Significantly better JOA and NDI scores were observed in Group A preoperatively and at the final follow-up, compared to Group B (P < .05). Disease duration was found significantly longer in patients with ISI (P < .05). Notably better JOA and NDI scores were noticed in Group B1 rather than Group B2 (P < .05). Logistical regression showed that disease duration was the only factor that significantly correlated with the progress of ISI (P < .001).CSM patients with ISI on T2W MR images had poorer surgical outcomes compared to others, while the increased range of HR may deteriorate preoperative neurological function. Moreover, patients with longer disease duration had greater risk of ISI in spinal cord.

Postoperative changes in spinal cord signal intensity in patients with spinal cord injury without major bone injury: comparison between preoperative and postoperative magnetic resonance images.

Although increased signal intensity (ISI) on MRI is observed in patients with cervical spinal cord injury (SCI) without major bone injury, alterations in ISI have not been evaluated. The association between postoperative ISI and surgical outcomes remains unclear. This study elucidated whether or not the postoperative classification and alterations in MRI-based ISI of the spinal cord reflected the postoperative symptom severity and surgical outcomes in patients with SCI without major bone injury. One hundred consecutive patients with SCI without major bone injury (79 male and 21 female) with a mean age of 55 years (range 20-87 years) were included. All patients were treated with laminoplasty and underwent MRI pre- and postoperatively (mean 12.5 ± 0.8 months). ISI was classified into three groups on the basis of sagittal T2-weighted MRI: grade 0, none; grade 1, light (obscure); and grade 2, intense (bright). The neurological statuses were evaluated according to the Japanese Orthopaedic Association (JOA) scoring system and the American Spinal Injury Association Impairment Scale (AIS). Preoperatively, 8 patients had grade 0 ISI, 49 had grade 1, and 43 had grade 2; and postoperatively, 20 patients had grade 0, 24 had grade 1, and 56 had grade 2. The postoperative JOA scores and recovery rate (RR) decreased significantly with increasing postoperative ISI grade. The postoperative ISI grade tended to increase with the postoperative AIS grade. Postoperative grade 2 ISI was observed in severely paralyzed patients. The postoperative ISI grade improved in 23 patients (23%), worsened in 25 (25%), and remained unchanged in 52 (52%). Patients with an improved ISI grade had a better RR than those with a worsened ISI grade. Postoperative ISI reflected postoperative symptom severity and surgical outcomes. Alterations in ISI were seen postoperatively in 48 patients (48%) and were associated with surgical outcomes.

Diffusion Tensor Imaging for Surgical Planning in Patients with Cervical Spondylotic Myelopathy.

Despite its invasiveness, computed tomography myelography (CTM) is still considered an important supplement to conventional magnetic resonance imaging (MRI) for preoperative evaluation of multilevel cervical spondylotic myelopathy (CSM). We analyzed if diffusion tensor imaging (DTI) could be a less invasive alternative for this purpose. In 20 patients with CSM and an indication for decompression of at least one level, CTM was performed preoperatively to determine the extent of spinal canal/cerebrospinal fluid (CSF) space and cord compression (Naganawa score) for a decision on the number of levels to be decompressed. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were correlated with these parameters and with MRI-based increased signal intensity (ISI). Receiver operating characteristic analysis was performed to determine the sensitivity to discriminate levels requiring decompression surgery. European Myelopathy Score (EMS) and neck/radicular visual analog scale (VAS-N/R) were used for clinical evaluation. According to preoperative CTM, 20 levels of maximum and 16 levels of relevant additional stenosis were defined and decompressed. Preoperative FA and particularly ADC showed a significant correlation with the CTM Naganawa score but also with the ISI grade. Furthermore, both FA and ADC facilitated a good discrimination between stenotic and nonstenotic levels with cutoff values < 0.49 for FA and > 1.15 × 10-9 m2/s for ADC. FA and especially ADC revealed a considerably higher sensitivity (79% and 82%, respectively) in discriminating levels requiring decompression surgery compared with ISI (55%). EMS and VAS-N/R were significantly improved at 14 months compared with preoperative values. DTI parameters are highly sensitive at distinguishing surgical from nonsurgical levels in CSM patients and might therefore represent a less invasive alternative to CTM for surgical planning.

Does three-grade classification of T2-weighted increased signal intensity reflect the severity of myelopathy and surgical outcomes in patients with cervical compressive myelopathy? A systematic review and meta-analysis.

The three-grade classification of increased signal intensity (ISI) on T2-weighted magnetic resonance imaging (MRI) is used extensively in patients with cervical compressive myelopathy (CCM). However, the efficacy and value in the prediction of this classification are still unclear and no systematic review and meta-analysis have been conducted on this topic. The objective of this study is to investigate the efficacy and value in prediction of the three-grade classification of ISI on the severity of myelopathy and surgical outcomes. Randomized or non-randomized controlled studies using three-grade classification of ISI (grade 0, none; grade 1, light or obscure; and grade 2, intense or bright) in patients with CCM were sought in the following databases: PubMed, Embase, and Cochrane Library. The pooled Japanese Orthopedic Association (JOA)/modified JOA (mJOA) score, neuro-functional recovery rate, C2-C7 lordotic angle, and range of motion (ROM) were calculated. A total of 8 studies containing 1101 patients were included in this review. Patients in grade 0 had the highest preoperative and postoperative JOA/mJOA score and recovery rate, while those parameters for patients in grade 2 were the lowest. Nevertheless, no statistically significant difference was found regarding the preoperative C2-C7 lordotic angle and ROM among three grades. Our meta-analysis suggests that the three-grade classification of ISI on T2-weighted MRI can reflect the severity of myelopathy and surgical outcomes in patients with CCM. The higher ISI grade indicates more severe myelopathy and surgical outcomes. Overall, the three-grade classification of ISI is instructive and should be used universally.

MR T2 image classification in adult patients of cervical spinal cord injury without radiographic abnormality: A predictor of surgical outcome

ObjectivesAlthough patients with cervical spinal cord injury without radiographic abnormality (SCIWORA) present increased signal intensity (ISI) on magnetic resonance imaging (MRI), its degree has not been examined. This study evaluated the clinical effectiveness of MRI-based ISI in adult patients of SCIWORA. Its predictive value for symptom severity was also evaluated. Patients and methodsOne-hundred consecutive SCIWORA patients who had undergone expansive laminoplasty were enrolled. Among them, 79 were male and 21 were female. The mean age was 55 years (range 20–87). All patients underwent MRI in the acute phase, and ISI was classified into three groups based on sagittal T2-weighted MRI: Grade 0, none; Grade 1, light (obscure); and Grade 2, intense (bright). The pre- and postoperative neurological status was evaluated using the Japanese Orthopaedic Association scoring system for cervical myelopathy (JOA score) and the ASIA impairment scale (AIS). ResultsPreoperative MRI showed Grade 0 in 8 patients, Grade 1 in 49 patients, and Grade 2 in 43 patients. There were no differences in age and gender among three groups. The pre- and postoperative JOA scores decreased significantly with an increasing ISI grade. The recovery rate of JOA score decreased with the ISI grade. The ISI grade tended to increase with the pre- and postoperative AIS grades. ISI Grade 2 on MRI was observed in severely paralyzed cases. ConclusionsMRI-based ISI classification is correlated with preoperative symptom severity in adult patients with SCIWORA and can be a predictor of surgical outcome.

MRI Signal Intensity Classification in Cervical Ossification of the Posterior Longitudinal Ligament: Predictor of Surgical Outcomes.

Prospective cohort study. To investigate whether classification of increased signal intensity (ISI) on magnetic resonance imaging (MRI) of spinal cord in patients with cervical ossification of the posterior longitudinal ligament (C-OPLL) reflects severity of myelopathy and surgical outcome. The relationship between classification of ISI on C-OPLL and severity is unknown. The 119 consecutive patients (91 men, 28 women) with C-OPLL who underwent surgery were enrolled. T2-weighted MRI was performed before surgery and ISI was classified into three groups as follows, Grade 0, none; Grade 1, light (obscure); and Grade 2, intense (bright). The severity of myelopathy and surgical outcome were evaluated by the Japanese Orthopedic Association score. To determine factors that influence ISI, the change of the spinal cord cross-sectional area (SCA) during flexion and extension was calculated by computed tomography after myelography. The preoperative MRI showed 55 patients in Grade 0, 46 patients in Grade 1, and 18 patients in Grade 2. The preoperative Japanese Orthopedic Association score (Grade 0, 11.2; Grade 1, 10.3; Grade 2, 9.6 points) and surgical outcome got worsened with increasing ISI grade. The patients in Grade 2 had a longer duration of disease, while those in Grade 1 and Grade 2 had a larger change of SCA during flexion and extension (Grade 0, 4.8 mm; Grade 1, 7.3 mm; Grade 2, 7.8 mm). However age, alignment of the cervical spine, range of motion, and occupying ratio of the ossification were not different in the three grades. Grade of ISI correlated with preoperative severity of myelopathy and surgical outcome in patients with C-OPLL. Increased signal intensity of the spinal cord on MRI was associated with a larger change in SCA and longer duration of disease. 3.

Delayed Magnetic Resonance Imaging in Patients With Cervical Spinal Cord Injury Without Radiographic Abnormality.

A prospective imaging study to develop diagnostic criteria. The aim of this study was to investigate image findings on delayed magnetic resonance imaging (MRI) after the acute phase of spinal cord injury without radiographic abnormality (SCIWORA) and their relationship with symptom severity. MRI is used to diagnose acute neurological injury, with increased signal intensity (ISI) and prevertebral hyperintensity (PVH) often seen in patients with SCIWORA; however, changes after the acute phase are unclear. We included 68 patients diagnosed with SCIWORA within 48 hours of injury. We then compared their acute (within 2 days) and delayed (after 2 weeks) MRI images. ISI grade (0-3) and ISI and PVH ranges (relative to the C3 vertebral height) were measured. Neurological status at admission and 2 weeks after injury was assessed by the Japanese Orthopaedic Association scoring system for cervical myelopathy (JOA score) and the American Spinal Injury Association impairment scale. For acute MRI, the rates of grade 0, 1, and 2 ISI were 4, 54, and 10 patients, respectively. For delayed MRI, the rates of grade 0, 1, and 2 ISI changed to 3, 31, and 34 patients, respectively. ISI ranges reduced in delayed MRI, but there was no significance. PVH ranges were 3.0 ± 1.7 in acute MRI, and reduced to 1.3 ± 0.9 with significant difference (P < 0.001). There were significant negative correlations with the JOA score for ISI grades on delayed MRI only (r = -0.49). However, there were significant negative correlations with the JOA score for the PVH range on both the acute (r = -0.55) and delayed (r = -0.46) MRI. When comparing acute and delayed MRI, there were significant differences in ISI and PVH findings. Delayed MRI also reflected the clinical symptom severity, giving useful information about the state of the spinal cord. 3.

Surgical outcome and prognostic factors of anterior decompression and fusion for cervical compressive myelopathy due to ossification of the posterior longitudinal ligament

Background contextAnterior decompression and fusion (ADF) for ossification of the posterior longitudinal ligament (OPLL) is technically demanding and associated with complications. Although various factors affecting clinical outcome have been investigated in posterior decompression, prognostic factors of ADF remain unclear. PurposeThe purpose of the study was to identify surgical outcome and prognostic factors of ADF for cervical myelopathy due to OPLL. Study designThis was a retrospective case study. Patient sampleBetween 2005 and 2012, 913 patients underwent decompression surgery for cervical OPLL at our institution. Among them, 131 who underwent ADF and 221 who underwent laminoplasty were enrolled. Inclusion criteria were (1) diagnosis of OPLL; (2) cervical compressive myelopathy; and (3) no trauma, infection, tumor, or previous surgery. We excluded 60 patients with ADF and 157 patients with laminoplasty owing to inadequate follow-up or absence of preoperative myelopathy. Finally, 71 patients with ADF and 64 patients with laminoplasty were enrolled in this study (mean follow-up, 48 vs 41 months). Outcome measuresNeurologic assessment was conducted using the Japanese Orthopedic Association (JOA) scoring system for cervical myelopathy. Rate of neurologic improvement was calculated by comparing preoperative and postoperative JOA scores. MethodsWe investigated the effects of such variables as age, gender, body mass index (BMI), presence of diabetes mellitus (DM), smoking history, type of OPLL, shape of the ossified lesion, occupying ratio of OPLL, presence of intramedullary increased signal intensity (ISI) on magnetic resonance imaging (MRI), and sagittal alignment of the cervical spine on surgical outcome. Severity of ISI was classified into three groups based on T2-weighted sagittal MRI as follows: Grade 0, none; Grade 1, ISI limited to one disc level; or Grade 2, ISI beyond one disc level. This work was supported by the 2013 Korea Health Technology R&D Project of the Ministry of Health and Welfare of the Republic of Korea (A120254). ResultsIn patients with an occupying ratio ≥60% or with presence of ISI on MRI, ADF yielded better surgical outcome than laminoplasty. A higher ISI grade (B=−28.5, p=.000) and a higher occupying ratio (B=0.88, p=.04) were significantly associated with a lower recovery rate (R=0.56, p=.006). Older age also was associated with a lower recovery rate. Gender, BMI, presence of DM, smoking history, type of OPLL, shape of the ossified lesion, and cervical alignment were not associated with recovery rate. ConclusionAnterior decompression and fusion has favorable outcome in patients with an occupying ratio ≥60% or with presence of ISI on MRI. Presence of higher ISI grade, higher occupying ratio, and older age were associated with a poor long-term surgical prognosis. Therefore, evaluating ISI and occupying ratio on preoperative MRI is important for selecting the appropriate surgical approach and for predicting clinical outcome after surgery for cervical compressive myelopathy due to OPLL.

Change in morphology of intramedullary T2-weighted increased signal intensity after anterior decompressive surgery for cervical spondylotic myelopathy.

Retrospective study. To study the change in morphology of T2-weighted (T2W) increased signal intensity (ISI) and its association with functional outcome after central corpectomy for cervical spondylotic myelopathy (CSM) and ossified posterior longitudinal ligament (OPLL). There are limited data on change in T2W ISI morphology after anterior decompressive surgery. It is unclear whether change in T2W ISI carries prognostic significance in patients with CSM/OPLL. We reviewed patients who underwent central corpectomy for CSM/OPLL between 1996 and 2010, and underwent a follow-up magnetic resonance imaging (MRI) at 6 months or later postoperatively. T2W ISI on sagittal images was classified as type 0 no ISI; type 1, predominantly (>50%) faint with an indistinct border; and type 2, predominantly (>50%) intense with a sharp border. The length of T2W ISI and the presence of T1-weighted hypointensity were also recorded on preoperative and follow-up images. Functional outcomes as measured by the Nurick grade were correlated with change in morphology of MR signal changes. Sixty-four patients (60 males, mean age = 50 ± 1.1 yr) were reviewed. The mean follow-up duration was 29 ± 3.5 months. The majority of patients (71.9%) had no change in the type of ISI at follow-up. The type of ISI improved in 13 patients (20.3%), and worsened in 5 patients (7.8%). The mean length of ISI was 26.2 ± 3.4 mm preoperatively and 13.7 ± 1.8 mm at follow-up in 53 patients (P = 0.002). Change in ISI grade or length was not associated with change in Nurick grade at follow-up (P = 0.74, P = 0.5). The type of T2W ISI does not change, but the length of T2W ISI decreases for the majority of patients undergoing anterior cervical decompression for CSM/OPLL. In our series, change in morphology of T2W ISI did not correlate with functional outcome as measured by Nurick grade. 4.