CT morphometric analysis of the cervical spinal canal with special reference to the correlation with the vertebral level.

BACKGROUND: Narrowness of the spinal canal is associated with the development of cervical myelopathy. While studies have addressed the sagittal diameter of the cervical spinal canal, few evaluated the correlation between the size of the spinal canal and the vertebral level. We addressed this issue. METHODS: Our retrospective study included 102 patients with cranial or spinal disorders. We examined the correlation between the cervical spinal canal diameter (SCD) at C1 to C7 and the inner anteroposterior diameter (IAPD) of the atlas on CT images. RESULTS: At C1, the SCD was largest, at C4 it was smallest. While there was a strong correlation between the IAPD and the SCD at C1 (r = 0.8), the correlation between the size of the atlas and the SCD at C4 to C7 was weak (r = 0.2-0.3). We divided our patients into a normal group (n = 34, SCD ≥ 12 mm at any levels) and a stenosis group (n = 68, SCD < 12 mm at all levels). The mean SCD at C2 to C7 was significantly larger in the normal group. There was no significant difference between the two groups with respect to the IAPD and the SCD at C1. CONCLUSIONS: The size of the subaxial spine does not necessarily affect the size of the atlas. The pathophysiology of spinal canal stenosis should be considered separately at the C1- and the subaxial level.

Measurement of Cervical Sagittal Alignment Parameters on X-Ray Films of Adults without Severe Spinal Deformity Whose Shoulder Hides the Lower Cervical Column.

OBJECTIVE: The Cobb angle between the lower endplate of C2 and C7 (C2L-C7L angle) is a traditional parameter used for the assessment of the cervical alignment. However, when the lower cervical column is masked by the shoulder, measurements are difficult. In the present study, we inspected 191 X-ray films, measured the Cobb angle between C2L and the endplates at the several levels of the lower cervical column, and assessed their usefulness of such measurements for the determination of cervical sagittal alignment. METHODS: We obtained X-ray films on 191 patients ranging in age from 20 to 93 years. The Cobb angle between C2L and the C7 upper (C7U), the C6 lower (C6L), the C6 upper (C6U), and the C5 lower endplate (C5L) was measured and compared with the C2L-C7L angle. RESULTS: C7L was identified in 116 of 191 patients (60.7%). Except for C2L-C7U angle (P = 0.55), the difference in the mean between C2L-C7L angle and the angle between C2L and the other endplates was statistically significant (P < 0.05). There was a very strong correlation between C2L-C7L angle and C2L-C7U angle (r = 0.99), C2L-C6L angle (r = 0.96), C2L-C6U angle (r = 0.94), and C2L-C5L angle (r = 0.86). CONCLUSIONS: To measure the C2L-C7L angle on unclear X-ray films, C7U can be substituted for C7L. Our measurement data for the C6 and C5 endplates were statistically different; however, the correlation between the C2L-C7L angle and C2L-C6U angle, C2L-C6L angle or C2L-C5L angle was very strong. In patients with unclear lower vertebral bodies, cervical sagittal alignment can be predicted by using adjacent endplates.

Is the atlas size associated with the pathophysiology of symptomatic spinal canal stenosis at the C1 level?

Narrow cervical spinal canal is an important risk factor for the development of cervical myelopathy. Patients with this disease often present with congenital narrowness of the cervical spinal canal. While there are studies on patients with subaxial spinal canal stenosis (SAS), few examined the coexistence of congenital narrow spinal canal in patients with cervical myelopathy at the C1 level. We investigated the characteristics of patients with C1 stenosis (C1S) with special reference to the size of the atlas. Thirteen patients (8 men, 5 women, mean age 76 years) with C1S were retrospectively analyzed and their clinical characteristics and radiological findings were compared with 27 SAS patients and with 26 age-, sex-, and body habitus-matched asymptomatic individuals. Of the 13 C1S patients, 6 presented with a retro-odontoid pseudotumor, 5 with atlantoaxial subluxation, and 2 with ossification or calcification of the transverse ligament; they were significantly older and shorter, and their body weight was significantly lower than in SAS patients (p < 0.001). Their average C1 anteroposterior- and spinal canal diameter was 26.9 ±â€¯2.4 mm and 12.8 ±â€¯4.1 mm, respectively and significantly smaller than in patients with subaxial stenosis (p = 0.004). These measurements were also statistically smaller than in the controls, even after matching for age, gender, height, and body weight (p < 0.05). In patients with C1S, the atlas size was significantly smaller than in SAS patients and asymptomatic controls, indicating an association between a small atlas size and symptomatic spinal canal stenosis at the C1 level.

Cervical Periosteal Chondroma Causing Spinal Cord or Nerve Compression: 2 Case Reports and Literature Review.

BACKGROUND: Chondroma is a rare benign cartilaginous tumor that originates in chondrocytes and is commonly seen in the long bones; however, it infrequently occurs in the cervical spine. CASE DESCRIPTIONS: We report 2 patients with cervical periosteal chondroma that originated in the C2 vertebral body and C1 lamina as extramedullary tumors. The first patient was a 28-year-old man who presented with right upper extremity weakness and numbness. Cervical radiography revealed a bony tumor with evidence of severe spinal cord compression. The second patient was a 26-year-old woman with left occipital neuralgia. Cervical radiography demonstrated a bony tumor arising from the left C1 lateral mass that compressed the C2 nerve root. Both patients underwent surgical removal of the bony tumors, which were diagnosed as periosteal chondroma. CONCLUSIONS: The authors herein summarized 16 previous reports of cervical chondroma and compared the clinical courses and treatments. Recommended treatment included maximal surgical resection, especially when significant compression of the cervical cord and signal abnormality within the cord was observed. Annual postoperative follow-up is mandatory to ensure proper neurologic improvement.

What Is the Most Representative Parameter for Describing the Size of the Atlas? CT Morphometric Analysis of the Atlas with Special Reference to Atlas Hypoplasia.

The spinal canal diameter (SCD) is one of the most studied factors for the assessment of cervical spinal canal stenosis. The inner anteroposterior diameter (IAP), the SCD, and the cross-sectional area (CSA) of the atlas have been used for the evaluation of the size of the atlas in patients with atlas hypoplasia, a rare form of developmental spinal canal stenosis, however, there is little information on their relationship. The aim of this study was to identify the most useful parameter for depicting the size of the atlas. The CSA, the IAP, and the SCD were measured on computed tomography (CT) images at the C1 level of 213 patients and compared in this retrospective study. These three parameters increased with increasing patient height and weight. There was a strong correlation between IAP and SCD (r = 0.853) or CSA (r = 0.822), while correlation between SCD and CSA (r = 0.695) was weaker than between IAP and CSA. Partial correlation analysis showed that IAP was positively correlated with SCD (r = 0.687) and CSA (r = 0.612) when CSA or SCD were controlled. SCD was negatively correlated with CSA when IAP was controlled (r = -0.21). The IAP can serve as the CSA for the evaluation of the size of the atlas ring, while the SCD does not correlate with the CSA. As the patient height and weight affect the size of the atlas, analysis of the spinal canal at the C1 level should take into account physiologic patient data.

Ginkgo leaf sign: a highly predictive imaging feature of spinal meningioma.

OBJECT Spinal meningioma and schwannoma are the most common spinal intradural extramedullary tumors, and the differentiation of these 2 tumors by CT and MRI has been a matter of debate. The purpose of this article is to present a case series of spinal meningiomas showing unique imaging features: a combination of a fan-shaped spinal cord and a streak in the tumor. The authors termed the former imaging feature "ginkgo leaf sign" and evaluated its diagnostic value. METHODS The authors present 7 cases of spinal meningioma having the ginkgo leaf sign. Thirty spinal extramedullary tumors arising lateral or ventrolateral to the spinal cord were studied to evaluate the diagnostic value of the ginkgo leaf sign for spinal meningiomas. Among 30 cases, 12 tumors were spinal meningiomas and 18 tumors from the control group were all schwannomas. RESULTS Seven of the 12 spinal meningiomas were positive for the ginkgo leaf sign. The sign was not present in the control group tumors. The overall ability to use the ginkgo leaf sign to detect meningioma indicated a sensitivity of 58%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 78%. CONCLUSIONS The ginkgo leaf sign is highly specific to spinal meningiomas arising lateral or ventrolateral to the spinal cord. In the present series, the ginkgo leaf sign was perfectly predictive for spinal meningioma.

MRI findings in patients with central neurocytomas with special reference to differential diagnosis from other ventricular tumours near the foramen of Monro.

We retrospectively evaluated 12 patients with histologically verified central neurocytoma (CN) to identify the MRI characteristics associated with this tumour. All tumours had heterogeneous signal intensity in their solid components and seven had a "soap bubble" or spongy appearance. Spicules were identified at the tumour periphery interfacing with the lateral ventricular walls. These spicules were formed by walls of multiple cysts of medium size. Undulation of the lateral ventricular wall attached to the tumour capsule was seen in nine patients. These spicules and undulations resulted in a "scalloping" appearance. In a diagnostic experiment to test the differential diagnosis of CN from other neoplasms near the foramen of Monro, the identification of scalloping made a greater contribution to the specificity and accuracy of the diagnosis than the soap bubble appearance. Thus, recognition of multiple cystic interfaces between the solid part of the tumour and the lateral ventricular wall on MRI may contribute to a correct preoperative diagnosis of CN.

TLR4, IL-6, IL-18, MyD88 and HMGB1 are highly expressed in intracranial inflammatory lesions and the IgG4/IgG ratio correlates with TLR4 and IL-6.

We determined distribution of plasma cells and IgG4/IgG index and factors associated with the index in intracranial inflammatory lesions. Specimens of nine patients were analyzed immunohistochemically using antibodies against CD45, CD68, CD3, CD4, CD8, CD20, CD138, lambda chain, kappa chain, IgG, IgG4, IL-1α, IL-6, IL-18, toll-like receptor (TLR) 2, TLR4, high-mobility group box 1 (HMGB1), tumor necrosis factor-alpha (TNF-α), myeloid differentiation factor 88 (MyD88), and anaplastic lymphoma kinase (ALK). The relationship between all the factors was assessed using Spearman's rank correlation coefficient (ρ). Negative ALK staining was observed in all the patients. Plasma cells were detected in eight patients with varying degrees. The highest number of neutrophils, but no plasma cells, was observed in a patient with the shortest history of inflammation. IgG4/IgG index was independent of the number of plasma cells. The index was relatively highly correlated with IL-6 (ρ = 0.7271) and TLR4 expression (ρ = 0.7246). IL-6 expression was highly correlated with TLR4 expression (ρ = 0.8042). IL-18 was maximally expressed in all the patients. TLR4 expression was strong, but TRL2 expression was weak. Positive HMGB1 staining was observed in all the patients, predominantly in the nuclei, but also in the cytoplasm in four patients. The cytoplasmic expression strongly correlated with IL-1α expression (ρ = 0.9583). The cytoplasmic colocalization of HMGB1 and IL-1α was histologically confirmed in cells with collapsing nuclei by the double-staining method. The IgG4/IgG indexes varied case by case. IL-6 and TLR4 expressions may influence IgG4/IgG index. The nuclei of cells with both IL-1α and HMGB1 expressions in the cytoplasm collapse in the cell death stage. The cooperative high expression of TLR4, IL-6, IL-18, MyD88 and HMGB1 suggest their critical roles in the inflammation circuit.