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991.
Charcot spinal arthropathy is a rare, progressive type of vertebral joint degeneration that occurs in the setting of any preexisting condition characterized by decreased afferent innervation to the extent that normal protective joint sensation in the vertebral column is impaired. The authors report on a case of Charcot arthropathy of the lower lumbar spine mimicking a spinal tumor following cervical cord injury.  相似文献   
992.

Objective

Spinal cord hemangioblastoma is an uncommon vascular neoplasm with a benign nature and is associated with von Hippel-Lindau (VHL) disease in 20-30% of patients. Total removal of these tumors without significant neurological deficit remains a great challenge. The purpose of this study was to investigate the efficacy of VHL mutation analysis and to evaluate surgical outcome of patients with spinal cord hemangioblastomas.

Methods

This study included nine patients treated for spinal cord hemangioblastomas at our institute between December 1994 and March 2006. There were four male and five female patients. Mean age was 37.8 years. The mean follow-up period was 22.4 months. Magnetic resonance imaging (MRI) of the complete neuraxis was done in all cases and VHL mutation analysis was performed in three cases for a definite diagnosis.

Results

Six patients had intramedullary tumor, and the remaining patients had intradural extramedullary lesions. Five patients were associated with VHL disease. The von Hippel-Lindau mutation analysis was done in three patients and two of them showed VHL gene abnormality. Tumors were located in the cervical cord in five cases and in the thoracic cord in four cases. All patients underwent surgical intervention, and total removal was achieved in six cases. All patients showed improvement or, at least, clinically stationary state. Surgical complications did not develop in any cases.

Conclusion

Spinal hemangioblastoma in this series has been safely and effectively removed via a posterior approach. Postoperatively, clinical outcome was excellent in the majority of cases. The VHL mutation analysis was useful in patients with family history and in those with multiple hemangioblastomas.  相似文献   
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Cervical epidural steroid injection is frequently used in the conservative management of neck pain and cervical radiculopathy. Epidural cervical transforaminal injections are usually well-tolerated with mild side effects such as transient decreased sensory and motor function, or headache due to dural puncture. Although there are a few case reports about adverse effects of cervical epidural injection in the literature, it can cause severe complications such as large hematoma, infarction by spinal vascular injury. Subdural hematoma has been occurred much less common rather than epidural hematoma in the spinal cord. We report a rare catastrophic case of cervical spinal subdural hematoma with quadriparesis after cervical transforaminal epidural block.  相似文献   
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Brain functional connectivity (FC) extracted from resting‐state fMRI (RS‐fMRI) has become a popular approach for diagnosing various neurodegenerative diseases, including Alzheimer's disease (AD) and its prodromal stage, mild cognitive impairment (MCI). Current studies mainly construct the FC networks between grey matter (GM) regions of the brain based on temporal co‐variations of the blood oxygenation level‐dependent (BOLD) signals, which reflects the synchronized neural activities. However, it was rarely investigated whether the FC detected within the white matter (WM) could provide useful information for diagnosis. Motivated by the recently proposed functional correlation tensors (FCT) computed from RS‐fMRI and used to characterize the structured pattern of local FC in the WM, we propose in this article a novel MCI classification method based on the information conveyed by both the FC between the GM regions and that within the WM regions. Specifically, in the WM, the tensor‐based metrics (e.g., fractional anisotropy [FA], similar to the metric calculated based on diffusion tensor imaging [DTI]) are first calculated based on the FCT and then summarized along each of the major WM fiber tracts connecting each pair of the brain GM regions. This could capture the functional information in the WM, in a similar network structure as the FC network constructed for the GM, based only on the same RS‐fMRI data. Moreover, a sliding window approach is further used to partition the voxel‐wise BOLD signal into multiple short overlapping segments. Then, both the FC and FCT between each pair of the brain regions can be calculated based on the BOLD signal segments in the GM and WM, respectively. In such a way, our method can generate dynamic FC and dynamic FCT to better capture functional information in both GM and WM and further integrate them together by using our developed feature extraction, selection, and ensemble learning algorithms. The experimental results verify that the dynamic FCT can provide valuable functional information in the WM; by combining it with the dynamic FC in the GM, the diagnosis accuracy for MCI subjects can be significantly improved even using RS‐fMRI data alone. Hum Brain Mapp 38:5019–5034, 2017. © 2017 Wiley Periodicals, Inc.  相似文献   
996.
We evaluated the incidence and predictors of edge dissection of the calcified culprit plaque in patients with acute coronary syndrome (ACS) or stable angina (SA). Calcified plaque is not rare in patients with ACS, and compliance mismatch may create edge dissection of the calcified plaque to trigger ACS. However, little data are available on calcium edge dissection in relation to ACS. Pre-intervention intravascular ultrasound data were analyzed in 143 patients with ACS (n = 53) or SA (n = 90). Edge dissection of the calcified plaque was found in 14 patients (9.8 %). Patients were divided into two groups based on calcium edge dissection: group I (edge dissection, n = 14) and group II (no edge dissection, n = 129). Clinical and angiographic characteristics were largely similar between the two groups; however, ACS was more common in group I than in group II (64.3 vs. 34.1 %, respectively, p = 0.039). Intravascular ultrasound variables did not differ between the two groups except thrombus and reference measurements, with thrombus more frequently observed in group I than in group II (35.7 vs. 8.5 %, respectively, p = 0.010). Likewise, proximal and distal reference measurements were larger in group I than in group II. Multivariate analysis showed that ACS was the only independent predictor of calcium edge dissection (odds ratio 3.5, 95 % confidence interval 1.1–11.0, p = 0.034). Edge dissection of the calcified plaque was present and more common in ACS patients than in SA patients. Calcium edge dissection may play a role in the pathogenesis of ACS.  相似文献   
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