Analysis of ascending spinal tract degeneration in cervical spondylotic myelopathy using 3D anisotropy contrast single-shot echo planar imaging on a 3.0-T system

2011 ◽  
Vol 15 (6) ◽  
pp. 648-653 ◽  
Author(s):  
Takaaki Urakawa ◽  
Hitoshi Matsuzawa ◽  
Yuji Suzuki ◽  
Naoto Endo ◽  
Ingrid L. Kwee ◽  
...  

Object The authors assessed the role of 3D anisotropy contrast (3DAC) in evaluating specific ascending tract degeneration in patients with cervical spondylotic myelopathy (CSM). Methods The authors studied 10 patients (2 women, 8 men; mean age 59.8 ± 14.6 years) with CSM and spinal cord compression below the C2–3 disc level, as well as 10 healthy control individuals (3 women, 7 men; mean age 42.0 ± 24.1 years). Images of the cervical cord at the C2–3 level were obtained using a 3.0-T MR imaging system. Results Three-dimensional anisotropy contrast imaging clearly made possible tract-by-tract analysis of the fasciculus cuneatus, fasciculus gracilis, and spinocerebellar tract. Tract degeneration identified using 3DAC showed good correlation with a decline in fractional anisotropy. Degeneration of the fasciculus gracilis detected by “vector contrast” demonstrated a good correlation with Nurick grades. Conclusions The study unambiguously demonstrated that 3DAC imaging is capable of assessing ascending tract degeneration in patients with CSM. Degeneration of an individual tract can be easily identified as a vector contrast change on the 3DAC image, a reflection of quantitative changes in anisotropism, similar to fractional anisotropy. Excellent correlation between Nurick grades and fasciculus gracilis degeneration suggests potential application of 3DAC imaging for tract-by-tract clinical correlation.

Sensors ◽  
2020 ◽  
Vol 20 (11) ◽  
pp. 3013 ◽  
Author(s):  
Ariel Schwarz ◽  
Amir Shemer ◽  
Yossef Danan ◽  
Rachel Bar-Shalom ◽  
Hemy Avraham ◽  
...  

Biomedical planar imaging using gamma radiation is a very important screening tool for medical diagnostics. Since lens imaging is not available in gamma imaging, the current methods use lead collimator or pinhole techniques to perform imaging. However, due to ineffective utilization of the gamma radiation emitted from the patient’s body and the radioactive dose limit in patients, poor image signal to noise ratio (SNR) and long image capturing time are evident. Furthermore, the resolution is related to the pinhole diameter, thus there is a tradeoff between SNR and resolution. Our objectives are to reduce the radioactive dose given to the patient and to preserve or improve SNR, resolution and capturing time while incorporating three-dimensional capabilities in existing gamma imaging systems. The proposed imaging system is based on super-resolved time-multiplexing methods using both variable and moving pinhole arrays. Simulations were performed both in MATLAB and GEANT4, and gamma single photon emission computed tomography (SPECT) experiments were conducted to support theory and simulations. The proposed method is able to reduce the radioactive dose and image capturing time and to improve SNR and resolution. The results and method enhance the gamma imaging capabilities that exist in current systems, while providing three-dimensional data on the object.


2014 ◽  
Vol 20 (1) ◽  
pp. 93-101 ◽  
Author(s):  
Shinji Yamamoto ◽  
Ryu Kurokawa ◽  
Phyo Kim

Object Regional blood flow is decreased in experimental models of chronic spinal cord compression, and the alteration presumably contributes to the development of myelopathy. Cilostazol (Otsuka Pharmaceuticals Co.), a selective Type III phosphodiesterase inhibitor, has been shown to be neuroprotective in cerebral hypoperfusion animal models and clinically effective in preventing the recurrence of cerebral infarction. To investigate the neuroprotective effect of cilostazol on cervical spondylotic myelopathy, the preventive effect against progressive motor dysfunction and the loss of anterior horn motor neurons were assessed using a chronic cord compression model in rats. Methods To produce chronic cervical cord compression in male Wistar rats, thin polyurethane sheets (3 × 5 × 0.7 mm) that gradually expand over 48–72 hours by absorbing water were implanted under the C5–6 laminae. In sham operations, the sheets were momentarily placed and then immediately removed. This model has been shown to reproduce characteristic features of clinical cervical myelopathy, with progressive motor disturbances after a latency period and insidious neuronal loss preceding the onset of symptoms. In the treatment group, cilostazol (30 mg/kg/day) was orally administered to the rats once a day, starting the day after surgery and continuing through the entire observation period of 25 weeks. In the control group, vehicle solution was administered under the same protocol. Changes in motor function were monitored by measuring bilateral forepaw grip strength and the duration of forced running on a treadmill. Twenty-five weeks after surgery, cervical spinal cords were examined histopathologically. Results Cilostazol preserved both forepaw grip strength and forced running capability. The drug also preserved anterior horn motor neurons in the C5–6 spinal cord segment, which diminished in number in the untreated chronic compression group. The drug decreased the number of TUNEL-positive apoptotic cells. Conclusions These results indicate that cilostazol is neuroprotective in the chronically compressed cervical cord and is potentially useful in the treatment of cervical spondylotic myelopathy.


2014 ◽  
Vol 2014 ◽  
pp. 1-8
Author(s):  
Kazuhiro Ohtakara ◽  
Hiroaki Hoshi

Radiotherapy for acute metastatic epidural spinal cord compression (MESCC) involves conventional techniques and dose fractionation schemes, as it needs to be initiated quickly. However, even with rapid intervention, few paraplegic patients regain ambulation. Here, we describe the case of a mid-octogenarian who presented with severe pain and nonambulatory quadriparesis attributable to MESCC at the fifth cervical vertebra, which developed 10 months after the diagnosis of undifferentiated carcinoma of the gallbladder. Image-guided three-dimensional conformal radiotherapy (IG-3DCRT) was started with 25 Gy in 5 fractions followed by a boost of 12 Gy in 3 fractions, for which a field-in-field (FIF) technique was used to optimize the dose distribution. Despite the fact that steroids were not administered, the patient reported significant pain reduction and showed improved motor function 3 and 4 weeks after the IG-3DCRT, respectively. Over the following 4 months, her neurological function gradually improved, and she was consequently able to eat and change clothes without assistance and to walk slowly for 10–20 m using a walker. She succumbed to progression of abdominal disease 8.5 months after the IG-3DCRT. This case demonstrates that image-guided FIF radiotherapy with a dose-escalated hypofractionated regimen can potentially improve functional outcome and local control.


2017 ◽  
Vol 11 (6) ◽  
pp. 1008-1015 ◽  
Author(s):  
John Paul Kolcun ◽  
Lee Onn Chieng ◽  
Karthik Madhavan ◽  
Michael Y. Wang

<p>Dynamic spinal cord compression has been investigated for several years, but until the advent of open MRI, the use of dynamic MRI (dMRI) did not gain popularity. Several publications have shown that cervical cord compression is both static and dynamic. On many occasions the evaluation of cervical spondylotic myelopathy (CSM) is straightforward, but patients are frequently encountered with a significantly worse clinical examination than would be suggested by radiological images. In this paper, we present an extensive review of the literature in order to describe the importance of dMRI in various settings and applications. A detailed literature review was performed in the Medline and Pubmed databases using the terms “cervical spondylotic myelopathy”, “dynamic MRI”, “kinetic MRI”, and “myelomalalcia” for the period of 1980-2016. The study was limited to English language, human subjects, case series, retrospective studies, prospective reports, and clinical trials. Reviews, case reports, cadaveric studies, editorials, and commentaries were excluded. The literature search yielded 180 papers, 19 of which met inclusion criteria. However, each paper had evaluated results and outcomes in different ways. It was not possible to compile them for meta-analysis or pooled data evaluation. Instead, we evaluated individual studies and present them for discussion. We describe a number of parameters evaluated in 2661 total patients, including dynamic changes to spinal cord and canal dimensions, transient compression of the cord with changes in position, and the effects of position on the intervertebral disc. dMRI is a useful tool for understanding the development of CSM. It has found several applications in the diagnosis and preoperative evaluation of many patients, as well as certain congenital dysplasias and Hirayama disease. It is useful in correlating symptoms with the dynamic changes only noted on dMRI, and has reduced the incidence of misdiagnosis of myelopathy.</p>


2021 ◽  
Vol 26 (4) ◽  
pp. 785-793
Author(s):  
Kimihiro Ogisu ◽  
Masaaki Niino ◽  
Yusei Miyazaki ◽  
Seiji Kikuchi

Background: Normal-appearing white matter (NAWM) lesions are known to be present in multiple sclerosis (MS); however, it is not easy to distinguish these lesions from others in MRI. This study aimed to investigate the most useful value for estimating NAWM damage using fractional anisotropy (FA) histograms analysis. Methods: Data from patients with relapsing-remitting MS and healthy controls were analyzed using a 1.5T MRI system with SENSE-Head-8 coil. FA maps with diffusion- weighted images were acquired using a single-shot echo-planar imaging sequence. The median, standard deviation (SD), kurtosis, and skewness of white matter (WM) of each subject were compared between MS and healthy controls using an in-house application. Results: FA decrease in 8 patients with MS was observed upon comparison with 12 controls and leaned toward the left side. While the SDs of the healthy controls were not significantly different from those of patients with MS, patients with MS expressed significantly lower median values, and higher kurtosis and skewness compared to healthy controls. A trend for inverse associations existed between median and expanded disability status scale scores. Conclusion: Our data suggests that median FA values can allow for distinguishing between patients with MS and healthy controls with high accuracy.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ryckie G. Wade ◽  
Irvin Teh ◽  
Gustav Andersson ◽  
Fang-Cheng Yeh ◽  
Mikael Wiberg ◽  
...  

AbstractDiffusion tensor imaging (DTI) metrics, such as the fractional anisotropy (FA) and estimates of diffusivity are sensitive to the microstructure of peripheral nerves and may be displayed as tractograms. However, the ideal conditions for tractography of the roots of the brachial plexus are unclear, which represents the rationale for this study. Ten healthy adults were scanned using a Siemens Prisma (3T) and single-shot echo-planar imaging (b-value 0/1000 s/mm2, 64 directions, 2.5 mm3 with 4 averages; repeated in opposing phase encoding directions). Susceptibility correction and tractography were performed in DSI Studio by two independent raters. The effect of FA thresholding at increments of 0.01 (from 0.04 to 0.10) were tested. The mean FA varied between subjects by 2% (95% CI 1%, 3%). FA thresholds of 0.04, 0.05 and 0.06 all propagated 96% of tracts representing the roots; thresholding at 0.07 yielded 4% fewer tracts (p = 0.2), 0.08 yielded 11% fewer tracts (p = 0.008), 0.09 yielded 15% fewer tracts (p = 0.001) and 0.1 yielded 20% fewer tracts (p < 0.001). There was < 0.1% inter-rater variability in the measured FA and 99% agreement for tractography (κ = 0.92, p < 0.001). The fractional anisotropy thresholds required to generate tractograms of the roots of the brachial plexus appears to be lower than those used in the brain. We provide estimates of the probability of generating true tracts for each spinal nerve root of the brachial plexus, at different fractional anisotropy thresholds.


2021 ◽  
Author(s):  
Binglin Ye ◽  
◽  
Shuling Li ◽  
Fengqi Sun ◽  
Youfu Fan ◽  
...  

Review question / Objective: This systematic review aims to comprehensively assess the efficacy and safety of full-endoscopic cervical laminectomy and decompression versus anterior cervical decompression with fusion in treating cervical spondylotic myelopathy (CSM) patients. Condition being studied: Cervical spondylotic myelopathy (CSM) is a degenerative disease associated with cervical cord compression, which has increased significant health-related social costs and derived disabilities. Anterior cervical discectomy and fusion (ACDF) is the "gold standard" for the treatment of CSM. However, the application of ACDF may cause some complications. Recently, full-endoscopic cervical laminectomy and decompression have shown potential therapeutic effects for CSM. However, no systematic review or meta-analysis has focused on the effects of full-endoscopic cervical laminectomy and decompression in the treatment of CSM. This systematic review aims to comprehensively assess the efficacy and safety of full-endoscopic cervical laminectomy and decompression versus anterior cervical decompression with fusion in treating CSM patients.


2017 ◽  
Vol 23 (3) ◽  
pp. 259-268 ◽  
Author(s):  
Yì Xiáng J. Wáng ◽  
Min Deng ◽  
Yáo T. Li ◽  
Hua Huang ◽  
Jason Chi Shun Leung ◽  
...  

This study investigated a combined use of intravoxel incoherent motion (IVIM) parameters, Dslow ( D), PF ( f), and Dfast ( D*), for liver fibrosis evaluation. Sixteen healthy volunteers (F0) and 33 hepatitis-b patients (stage F1 = 15, stage F2–4 = 18) were included. With a 1.5 T MR scanner and respiration gating, IVIM diffusion-weighted imaging was acquired using a single-shot echo-planar imaging sequence with 10 b values of 10, 20, 40, 60, 80, 100, 150, 200, 400, and 800 s/mm2. Signal measurement was performed on right liver parenchyma. With a three-dimensional tool, Dslow, PF, and Dfast values were placed along the x axis, y axis, and z axis, and a plane was defined to separate healthy volunteers from patients. The three-dimensional tool demonstrated that healthy volunteers and all patients with liver fibrosis could be separated. Classification and regression tree showed that a combination of PF (PF < 12.55%), Dslow (Dslow < 1.152 × 10−3 mm2/s), and Dfast (Dfast < 13.36 × 10−3 mm2/s) could differentiate healthy subjects and all fibrotic livers (F1–4) with an area under the curve of logistic regression (AUC) of 0.986. The AUC for differentiation of healthy livers versus F2–4 livers was 1. PF offered the best diagnostic value, followed by Dslow; however, all three parameters of PF, Dslow, and Dfast contributed to liver fibrosis detection.


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