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Sample records for absorptiometry spine images

  1. Magnetic resonance imaging and dual energy X-ray absorptiometry of the lumbar spine in professional wrestlers and untrained men.

    PubMed

    Hu, M; Sheng, J; Kang, Z; Zou, L; Guo, J; Sun, P

    2014-08-01

    The aim of this study was to examine the relation between bone marrow adipose tissue (BMAT) and bone mineral density (BMD) of lumbar spine in male professional wrestlers and healthy untrained men. A total of 14 wrestlers (22.9±3.4 years) and 11 controls (24.4±1.6 years) were studied cross-sectionally. Body composition and BMD were measured by dual-energy X-ray absorptiometry. Magnetic resonance imaging of the lumbar spine was examined in a sagittal T1-weighted (T1-w) spin-echo (SE) sequence. The averaged bone marrow signal intensity (SI) of L2-L4 was related to the signal of an adjacent nondegenerative disk. Mean SI of T1-w SE in wrestlers was lower than controls (P=0.001), indicating L2-L4 BMAT in wrestlers was lower compared to controls. L2-L4 BMD in wrestlers was higher than controls (P<0.001). In the total subject population, L2-L4 BMD was inversely correlated with mean SI of T1-w SE (r=-0.62, P=0.001). This association remained strong after adjusting for body mass and whole lean mass, but became weaker after adjusting for whole body or trunk fat percentage. The inverse relationship between BMAT and BMD was confirmed in this relatively small subject sample with narrow age range, which implies that exercise training is an important determinant of this association.

  2. Dual energy X-ray absorptiometry spine scans to determine abdominal fat in postmenopausal women.

    PubMed

    Bea, J W; Blew, R M; Going, S B; Hsu, C-H; Lee, M C; Lee, V R; Caan, B J; Kwan, M L; Lohman, T G

    2016-11-01

    Body composition may be a better predictor of chronic disease risk than body mass index (BMI) in older populations. We sought to validate spine fat fraction (%) from dual energy X-ray absorptiometry (DXA) spine scans as a proxy for total abdominal fat. Total body DXA scan abdominal fat regions of interest (ROI) that have been previously validated by magnetic resonance imaging were assessed among healthy, postmenopausal women who also had antero-posterior spine scans (n = 103). ROIs were (1) lumbar vertebrae L2-L4 and (2) L2-Iliac Crest (L2-IC), manually selected by two independent raters, and (3) trunk, auto-selected by DXA software. Intra-class correlation coefficients evaluated intra and inter-rater reliability on a random subset (N = 25). Linear regression models, validated by bootstrapping, assessed the relationship between spine fat fraction (%) and total abdominal fat (%) ROIs. Mean age, BMI, and total body fat were 66.1 ± 4.8 y, 25.8 ± 3.8 kg/m 2 and 40.0 ± 6.6%, respectively. There were no significant differences within or between raters. Linear regression models adjusted for several participant and scan characteristics were equivalent to using only BMI and spine fat fraction. The model predicted L2-L4 (Adj. R 2 : 0.83) and L2-IC (Adj. R 2 : 0.84) abdominal fat (%) well; the adjusted R 2 for trunk fat (%) was 0.78. Model validation demonstrated minimal over-fitting (Adj. R 2 : 0.82, 0.83, and 0.77 for L2-L4, L2-IC, and trunk fat, respectively). The strong correlation between spine fat fraction and DXA abdominal fat measures make it suitable for further development in postmenopausal chronic disease risk prediction models. Am. J. Hum. Biol. 28:918-926, 2016. © 2016Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. Dual energy X-ray absorptiometry spine scans to determine abdominal fat in post-menopausal women

    PubMed Central

    Bea, J. W.; Blew, R. M.; Going, S. B.; Hsu, C-H; Lee, M. C.; Lee, V. R.; Caan, B.J.; Kwan, M.L.; Lohman, T. G.

    2016-01-01

    Body composition may be a better predictor of chronic disease risk than body mass index (BMI) in older populations. Objectives We sought to validate spine fat fraction (%) from dual energy X-ray absorptiometry (DXA) spine scans as a proxy for total abdominal fat. Methods Total body DXA scan abdominal fat regions of interest (ROI) that have been previously validated by magnetic resonance imaging were assessed among healthy, postmenopausal women who also had antero-posterior spine scans (n=103). ROIs were 1) lumbar vertebrae L2-L4 and 2) L2-Iliac Crest (L2-IC), manually selected by two independent raters, and 3) trunk, auto-selected by DXA software. Intra-class correlation coefficients evaluated intra and inter-rater reliability on a random subset (N=25). Linear regression models, validated by bootstrapping, assessed the relationship between spine fat fraction (%) and total abdominal fat (%) ROIs. Results Mean age, BMI and total body fat were: 66.1 ± 4.8y, 25.8 ± 3.8kg/m2 and 40.0 ± 6.6%, respectively. There were no significant differences within or between raters. Linear regression models adjusted for several participant and scan characteristics were equivalent to using only BMI and spine fat fraction. The model predicted L2-L4 (Adj. R2: 0.83) and L2-IC (Adj.R2:0.84) abdominal fat (%) well; the adjusted R2 for trunk fat (%) was 0.78. Model validation demonstrated minimal over-fitting (Adj. R2: 0.82, 0.83, and 0.77 for L2-L4, L2-IC, and trunk fat respectively). Conclusions The strong correlation between spine fat fraction and DXA abdominal fat measures make it suitable for further development in post-menopausal chronic disease risk prediction models. PMID:27416964

  4. Measurement of spine and total body mineral by dual-photon absorptiometry

    NASA Technical Reports Server (NTRS)

    Mazess, R. B.; Young, D.

    1983-01-01

    The use of Gd-153 dual-photon absorptiometry at 43 and 100 keV to measure individual-bone and total-body bone minerals is discussed in a survey of recent studies on humans, phantoms, and monkeys. Precision errors of as low as 1 percent have been achieved in vivo, suggesting the use of sequential measurements in studies of immobilization and space-flight effects.

  5. Intravital imaging of dendritic spine plasticity

    PubMed Central

    Sau Wan Lai, Cora

    2014-01-01

    Abstract Dendritic spines are the postsynaptic part of most excitatory synapses in the mammalian brain. Recent works have suggested that the structural and functional plasticity of dendritic spines have been associated with information coding and memories. Advances in imaging and labeling techniques enable the study of dendritic spine dynamics in vivo. This perspective focuses on intravital imaging studies of dendritic spine plasticity in the neocortex. I will introduce imaging tools for studying spine dynamics and will further review current findings on spine structure and function under various physiological and pathological conditions. PMID:28243511

  6. Automatic lumbar spine measurement in CT images

    NASA Astrophysics Data System (ADS)

    Mao, Yunxiang; Zheng, Dong; Liao, Shu; Peng, Zhigang; Yan, Ruyi; Liu, Junhua; Dong, Zhongxing; Gong, Liyan; Zhou, Xiang Sean; Zhan, Yiqiang; Fei, Jun

    2017-03-01

    Accurate lumbar spine measurement in CT images provides an essential way for quantitative spinal diseases analysis such as spondylolisthesis and scoliosis. In today's clinical workflow, the measurements are manually performed by radiologists and surgeons, which is time consuming and irreproducible. Therefore, automatic and accurate lumbar spine measurement algorithm becomes highly desirable. In this study, we propose a method to automatically calculate five different lumbar spine measurements in CT images. There are three main stages of the proposed method: First, a learning based spine labeling method, which integrates both the image appearance and spine geometry information, is used to detect lumbar and sacrum vertebrae in CT images. Then, a multiatlases based image segmentation method is used to segment each lumbar vertebra and the sacrum based on the detection result. Finally, measurements are derived from the segmentation result of each vertebra. Our method has been evaluated on 138 spinal CT scans to automatically calculate five widely used clinical spine measurements. Experimental results show that our method can achieve more than 90% success rates across all the measurements. Our method also significantly improves the measurement efficiency compared to manual measurements. Besides benefiting the routine clinical diagnosis of spinal diseases, our method also enables the large scale data analytics for scientific and clinical researches.

  7. Magnetic Resonance Imaging (MRI): Lumbar Spine (For Parents)

    MedlinePlus

    ... Staying Safe Videos for Educators Search English Español Magnetic Resonance Imaging (MRI): Lumbar Spine KidsHealth / For Parents / Magnetic Resonance Imaging (MRI): Lumbar Spine What's in this article? What ...

  8. Spine metastasis imaging: review of the literature.

    PubMed

    Guillevin, R; Vallee, J-N; Lafitte, F; Menuel, C; Duverneuil, N-M; Chiras, J

    2007-12-01

    Any malignant neoplasm possesses the capacity to metastasize to the musculoskeletal system. Because the spine is the most frequent site of bone metastasis, imaging must be discussed in cases of cancer. Bone marrow is the main interest in imaging the metastatic process by magnetic resonance, while X-rays allow the study of cortical involvement. This article presents our experience, and a review of the literature, in an overview of the different imaging techniques-X-rays and magnetic resonance-with emphasis on the many difficulties that can be encountered in the diagnosis and monitoring of spinal metastases, allowing a management strategy for diagnosis and follow-up.

  9. Virtual endoscopic imaging of the spine.

    PubMed

    Kotani, Toshiaki; Nagaya, Shigeyuki; Sonoda, Masaru; Akazawa, Tsutomu; Lumawig, Jose Miguel T; Nemoto, Tetsuharu; Koshi, Takana; Kamiya, Koshiro; Hirosawa, Naoya; Minami, Shohei

    2012-05-20

    Prospective trial of virtual endoscopy in spinal surgery. To investigate the utility of virtual endoscopy of the spine in conjunction with spinal surgery. Several studies have described clinical applications of virtual endoscopy to visualize the inside of the bronchi, paranasal sinus, stomach, small intestine, pancreatic duct, and bile duct, but, to date, no study has described the use of virtual endoscopy in the spine. Virtual endoscopy is a realistic 3-dimensional intraluminal simulation of tubular structures that is generated by postprocessing of computed tomographic data sets. Five patients with spinal disease were selected: 2 patients with degenerative disease, 2 patients with spinal deformity, and 1 patient with spinal injury. Virtual endoscopy software allows an observer to explore the spinal canal with a mouse, using multislice computed tomographic data. Our study found that virtual endoscopy of the spine has advantages compared with standard imaging methods because surgeons can noninvasively explore the spinal canal in all directions. Virtual endoscopy of the spine may be useful to surgeons for diagnosis, preoperative planning, and postoperative assessment by obviating the need to mentally construct a 3-dimensional picture of the spinal canal from 2-dimensional computed tomographic scans.

  10. Clinical application of dual photon absorptiometry (DPA) at the lumbar spine (LS) in the diagnosis of osteoporosis

    SciTech Connect

    Wahner, H.W.; Dunn, W.L.; Riggs, B.L.

    This study evaluates the effectiveness of DPA to separate patients with osteoporosis (greater than 2 spinal fractures, normal Ca, P, absence of drugs, and metabolic bone disease) from a normal population. Performance criteria for the instrument have been described previously. Data was obtained from a prospective study of 105 normal women, 75 patients with osteoporosis and a retrospective study of 300 patients with osteoporosis seen in 1982/83. The results were as follows: (1) Area density (gm/cm/sup 2/) was found superior to mass (gm) due to the occasional problem to clearly identify the boundaries of L1-4. (2) Separation of the twomore » populations was best when L1-L4,L2-L4, L3 alone or 10 paths over the mid lumbar area were used. One pass was not acceptable. (3) Compression fractures (CF) in the LS showed an increase in area density initially but area density may be undistinguishable from intact vertebrae later. To correct for this loss of bone area a factor predicting the area of lumbar vertebrae and based on patients actual height and weight was introduced and tested. (4) In the retrospective study a negative correlation was found between number of thoracic spine CF and bone mineral values in the LS. (5) A fracture threshold value of BM defined as the level below which 95% of all patients with CF were found was determined to be 0.98 g/cm2. Sixty-five percent of patients with two or more spinal CF could be separated from the normal population (outside 2SD). By using a correction factor for height loss this could be further increased to about 70%. CF in the LS may falsely elevate bone mineral values.« less

  11. Cervical Spine Imaging in Hospitalized Children with Traumatic Brain Injury

    PubMed Central

    Bennett, Tellen D.; Bratton, Susan L.; Riva-Cambrin, Jay; Scaife, Eric R.; Nance, Michael L.; Prince, Jeffrey S.; Wilkes, Jacob; Keenan, Heather T.

    2015-01-01

    Objectives In children with TBI, to describe cervical spine imaging practice, to assess for recent changes in imaging practice, and to determine if cervical spine CT is being used in children at low risk for cervical spine injury. Methods The setting was children’s hospitals participating in the Pediatric Health Information System database, January, 2001 to June, 2011. Participants were children (age < 18 years) with TBI who were evaluated in the Emergency Department, admitted to the hospital, and received a head CT scan on the day of admission. The primary outcome measures were cervical spine imaging studies. This study was exempted from IRB review. Results 30,112 children met study criteria. Overall, 52% (15,687/30,112) received cervical spine imaging. Use of cervical spine radiographs alone decreased between 2001 (47%) and 2011 (23%), annual decrease 2.2% (95% confidence interval [CI] 1.1–3.3%), largely replaced by increased use of CT, with or without radiographs (8.6% in 2001, 19.5% in 2011, annual increase 0.9%, 95% CI 0.1–1.8%). 2,545 children received a cervical spine CT despite being discharged alive from the hospital in < 72 hours, and 1,655 of those had a low-risk mechanism of injury. Conclusions The adoption of CT clearance of the cervical spine in adults appears to have influenced the care of children with TBI, despite concerns about radiation exposure. PMID:25803749

  12. Rheumatic diseases of the spine: imaging diagnosis.

    PubMed

    Narváez, J A; Hernández-Gañán, J; Isern, J; Sánchez-Fernández, J J

    2016-04-01

    Spinal involvement is common both in the spondyloarthritides and in rheumatoid arthritis, in which the cervical segment is selectively affected. Rheumatoid involvement of the cervical spine has characteristic radiologic manifestations, fundamentally different patterns of atlantoaxial instability. Magnetic resonance imaging (MRI) is the technique of choice for evaluating the possible repercussions of atlantoaxial instability on the spinal cord and/or nerve roots in patients with rheumatoid arthritis as well as for evaluating parameters indicative of active inflammation, such as bone edema and synovitis. Axial involvement is characteristic in the spondyloarthritides and has distinctive manifestations on plain-film X-rays, which reflect destructive and reparative phenomena. The use of MRI has changed the conception of spondyloarthritis because it is able to directly detect the inflammatory changes that form part of the disease, making it possible to establish the diagnosis early in the disease process, when plain-film X-ray findings are normal (non-radiographic axial spondyloarthritis), to assess the prognosis of the disease, and to contribute to treatment planning. Copyright © 2016 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

  13. Technical aspects of CT imaging of the spine.

    PubMed

    Tins, Bernhard

    2010-11-01

    This review article discusses technical aspects of computed tomography (CT) imaging of the spine. Patient positioning, and its influence on image quality and movement artefact, is discussed. Particular emphasis is placed on the choice of scan parameters and their relation to image quality and radiation burden to the patient. Strategies to reduce radiation burden and artefact from metal implants are outlined. Data acquisition, processing, image display and steps to reduce artefact are reviewed. CT imaging of the spine is put into context with other imaging modalities for specific clinical indications or problems. This review aims to review underlying principles for image acquisition and to provide a rough guide for clinical problems without being prescriptive. Individual practice will always vary and reflect differences in local experience, technical provisions and clinical requirements.

  14. Magnetic resonance imaging atlas of the cervical spine musculature.

    PubMed

    Au, John; Perriman, Diana M; Pickering, Mark R; Buirski, Graham; Smith, Paul N; Webb, Alexandra L

    2016-07-01

    The anatomy of the cervical spine musculature visible on magnetic resonance (MR) images is poorly described in the literature. However, the correct identification of individual muscles is clinically important because certain conditions of the cervical spine, for example whiplash associated disorders, idiopathic neck pain, cervical nerve root avulsion and cervical spondylotic myelopathy, are associated with different morphological changes in specific muscles visible on MR images. Knowledge of the precise structure of different cervical spine muscles is crucial when comparisons with the contralateral side or with normal are required for accurate description of imaging pathology, management and assessment of treatment efficacy. However, learning the intricate arrangement of 27 muscles is challenging. A multi-level cross-sectional depiction combined with three-dimensional reconstructions could facilitate the understanding of this anatomically complex area. This paper presents a comprehensive series of labeled axial MR images from one individual and serves as a reference atlas of the cervical spine musculature to guide clinicians, researchers, and anatomists in the accurate identification of these muscles on MR imaging. Clin. Anat. 29:643-659, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  15. Imaging investigations in Spine Trauma: The value of commonly used imaging modalities and emerging imaging modalities.

    PubMed

    Tins, Bernhard J

    2017-01-01

    Traumatic spine injuries can be devastating for patients affected and for health care professionals if preventable neurological deterioration occurs. This review discusses the imaging options for the diagnosis of spinal trauma. It lays out when imaging is appropriate and when it is not. It discusses strength and weakness of available imaging modalities. Advanced techniques for spinal injury imaging will be explored. The review concludes with a review of imaging protocols adjusted to clinical circumstances.

  16. The evolution of image-guided lumbosacral spine surgery.

    PubMed

    Bourgeois, Austin C; Faulkner, Austin R; Pasciak, Alexander S; Bradley, Yong C

    2015-04-01

    Techniques and approaches of spinal fusion have considerably evolved since their first description in the early 1900s. The incorporation of pedicle screw constructs into lumbosacral spine surgery is among the most significant advances in the field, offering immediate stability and decreased rates of pseudarthrosis compared to previously described methods. However, early studies describing pedicle screw fixation and numerous studies thereafter have demonstrated clinically significant sequelae of inaccurate surgical fusion hardware placement. A number of image guidance systems have been developed to reduce morbidity from hardware malposition in increasingly complex spine surgeries. Advanced image guidance systems such as intraoperative stereotaxis improve the accuracy of pedicle screw placement using a variety of surgical approaches, however their clinical indications and clinical impact remain debated. Beginning with intraoperative fluoroscopy, this article describes the evolution of image guided lumbosacral spinal fusion, emphasizing two-dimensional (2D) and three-dimensional (3D) navigational methods.

  17. Spine abnormalities depicted by magnetic resonance imaging in adolescent rowers.

    PubMed

    Maurer, Marvin; Soder, Ricardo Bernardi; Baldisserotto, Matteo

    2011-02-01

    Most lesions of the spine of athletes, which often are detected incidentally, do not cause important symptoms or make the athletes discontinue their physical activities. To better understand the significance of these lesions, new imaging studies have been conducted with asymptomatic athletes in several sports, aiming to detect potentially deleterious and disabling abnormalities. To compare the magnetic resonance imaging (MRI) lumbar spine findings in a group of asymptomatic adolescent rowers and in a control group of adolescents matched according to age and sex who do not practice any regular physical activity. Cohort study (prevalence); Level of evidence, 3. Our study evaluated 44 asymptomatic adolescent boys distributed in 2 groups of 22 rowers and 22 control subjects. All the examinations were performed using a 0.35-T open-field MRI unit and evaluated by 2 experienced radiologists blinded to the study groups. Each MRI scan was analyzed for the presence of disc degeneration/desiccation, herniated or bulging disc, pars interarticularis stress reaction, and spondylolysis. The Student t test and the Fisher exact test were used for statistical analyses. Nine rowers (40.9%) had at least 1 abnormality detected by MRI in the lumbar spine, whereas only 2 participants (9.1%) in the control group had at least 1 MRI abnormality (P = .03). Seven disc changes (31.8%) and 6 pars abnormalities (27.3%) were found in the group of elite rowers. In the control group, 3 disc changes (13.6%) and no pars abnormalities were found in the MR scans. The comparison between groups showed statistically significant differences in stress reaction of the pars articularis. Disc disease and pars interarticularis stress reaction are prevalent abnormalities of the lumbar spine of high-performance rowers.

  18. Imaging of acute cervical spine injuries: review and outlook.

    PubMed

    Tins, B J; Cassar-Pullicino, V N

    2004-10-01

    Advances in imaging technology have been successfully applied in the emergency trauma setting with great benefit providing early, accurate and efficient diagnoses. Gaps in the knowledge of imaging acute spinal injury remain, despite a vast wealth of useful research and publications on the role of CT and MRI. This article reviews in a balanced manner the main questions that still face the attending radiologist by embracing the current and evolving concepts to help define and provide answers to the following; Imaging techniques -- strengths and weaknesses; what are the implications of a missed cervical spine injury?; who should be imaged?; how should they be imaged?; spinal immobilisation -- help or hazard?; residual open questions; what does all this mean?; and what are the implications for the radiologist? Although there are many helpful guidelines, the residual gaps in the knowledge base result in incomplete answers to the questions posed. The identification of these gaps in knowledge however should act as the initiating stimulus for further research. All too often there is a danger that the performance and productivity of the imaging modalities is the main research focus and not enough attention is given to the two fundamental prerequisites to the assessment of any imaging technology -- the clinical selection criteria for imaging and the level of expertise of the appropriate clinician interpreting the images.

  19. Modeling the shape and composition of the human body using dual energy X-ray absorptiometry images

    PubMed Central

    Shepherd, John A.; Fan, Bo; Schwartz, Ann V.; Cawthon, Peggy; Cummings, Steven R.; Kritchevsky, Stephen; Nevitt, Michael; Santanasto, Adam; Cootes, Timothy F.

    2017-01-01

    There is growing evidence that body shape and regional body composition are strong indicators of metabolic health. The purpose of this study was to develop statistical models that accurately describe holistic body shape, thickness, and leanness. We hypothesized that there are unique body shape features that are predictive of mortality beyond standard clinical measures. We developed algorithms to process whole-body dual-energy X-ray absorptiometry (DXA) scans into body thickness and leanness images. We performed statistical appearance modeling (SAM) and principal component analysis (PCA) to efficiently encode the variance of body shape, leanness, and thickness across sample of 400 older Americans from the Health ABC study. The sample included 200 cases and 200 controls based on 6-year mortality status, matched on sex, race and BMI. The final model contained 52 points outlining the torso, upper arms, thighs, and bony landmarks. Correlation analyses were performed on the PCA parameters to identify body shape features that vary across groups and with metabolic risk. Stepwise logistic regression was performed to identify sex and race, and predict mortality risk as a function of body shape parameters. These parameters are novel body composition features that uniquely identify body phenotypes of different groups and predict mortality risk. Three parameters from a SAM of body leanness and thickness accurately identified sex (training AUC = 0.99) and six accurately identified race (training AUC = 0.91) in the sample dataset. Three parameters from a SAM of only body thickness predicted mortality (training AUC = 0.66, validation AUC = 0.62). Further study is warranted to identify specific shape/composition features that predict other health outcomes. PMID:28423041

  20. Handheld real-time volumetric imaging of the spine: technology development.

    PubMed

    Tiouririne, Mohamed; Nguyen, Sarah; Hossack, John A; Owen, Kevin; William Mauldin, F

    2014-03-01

    Technical difficulties, poor image quality and reliance on pattern identifications represent some of the drawbacks of two-dimensional ultrasound imaging of spinal bone anatomy. To overcome these limitations, this study sought to develop real-time volumetric imaging of the spine using a portable handheld device. The device measured 19.2 cm × 9.2 cm × 9.0 cm and imaged at 5 MHz centre frequency. 2D imaging under conventional ultrasound and volumetric (3D) imaging in real time was achieved and verified by inspection using a custom spine phantom. Further device performance was assessed and revealed a 75-min battery life and an average frame rate of 17.7 Hz in volumetric imaging mode. The results suggest that real-time volumetric imaging of the spine is a feasible technique for more intuitive visualization of the spine. These results may have important ramifications for a large array of neuraxial procedures.

  1. Economics of image guidance and navigation in spine surgery.

    PubMed

    Al-Khouja, Lutfi; Shweikeh, Faris; Pashman, Robert; Johnson, J Patrick; Kim, Terrence T; Drazin, Doniel

    2015-01-01

    Image-guidance and navigation in spinal surgery is becoming more widely utilized. Several studies have shown the use of this technology to increase accuracy of pedicle screw placement, decrease the rates of revision surgery, and minimize radiation exposure. In this paper, the authors analyze the economics of image-guided surgery (IGS) and navigation in spine surgery. A literature review was performed using PubMed, the CEA Registry, and the National Health Service Economic Evaluation Database. Each article was screened for inclusion and exclusion criteria, including costs, reoperation, readmission rates, operating room time, and length of stay. Thirteen studies were included in the analysis. Six studies were identified to meet the inclusion criteria for reporting costs and seven met the criteria for analysis of efficacy. Average costs ranged from $17,650 to $39,643. Pedicle screw misplacement rates using IGS ranged from 1.20% to 15.07% while reoperation rates ranged from 0% to 7.42%. There is currently an insufficient amount of studies reporting on the economics of spinal navigation to accurately conclude on its cost-effectiveness in clinical practice. Although a few of these studies showed less costs associated with intraoperative imaging, none were able to establish a statistically significant difference. Preliminary findings drawn from this study indicate a possible cost-effectiveness advantage with IGS, but more comprehensive data on costs need to be reported in order to validate its utilization.

  2. Outcomes of pediatric patients with persistent midline cervical spine tenderness and negative imaging result after trauma.

    PubMed

    Dorney, Kate; Kimia, Amir; Hannon, Megan; Hennelly, Kara; Meehan, William P; Proctor, Mark; Mooney, David P; Glotzbecker, Michael; Mannix, Rebekah

    2015-11-01

    There is little evidence to guide management of pediatric patients with persistent cervical spine tenderness after trauma but with negative initial imaging study findings. Our objective was to determine the prevalence of clinically significant cervical spine injury among pediatric blunt trauma patients discharged from the emergency department with negative imaging study findings but persistent midline cervical spine tenderness. We performed a single-center, retrospective study of subjects 1 year to 15 years of age discharged in a rigid cervical spine collar after blunt trauma over a 5-year period. We included patients with negative imaging results who were maintained in a collar because of persistent midline cervical spine tenderness. Primary outcome was clinically significant cervical spine injury. Secondary outcome was continued use of the collar after follow-up. Outcomes were ascertained from the medical record or self-report via telephone call. A total of 307 subjects met inclusion criteria, of whom 289 (94.1%) had follow-up information available (89.6% in chart, 10.4% via telephone call). Of those with follow-up information, 189 (65.4%) had subspecialty follow-up in the spine clinic. Of those with spine clinic follow-up, 84.6% had the hard collar discontinued at the first visit (median time to visit, 10 days). Of subjects with spine clinic follow-up, 10.1% were left in the collar for persistent tenderness without findings on imaging and 2.1% had imaging findings related to their injury; none required surgical intervention. A very small percentage of subjects with persistent midline cervical spine tenderness and normal radiographic study findings have a clinically significant cervical spine injury identified at follow-up. Referral for subspecialty evaluation may only be necessary in a small number of patients with persistent tenderness or concerning signs/symptoms. Therapeutic study, level IV.

  3. Methods of Dendritic Spine Detection: from Golgi to High Resolution Optical Imaging

    PubMed Central

    Mancuso, James J; Chen, Yuanxin; Li, Xuping; Xue, Zhong

    2012-01-01

    Dendritic spines, the bulbous protrusions that form the postsynaptic half of excitatory synapses, are one of the most prominent features of neurons and have been imaged and studied for over a century. In that time, changes in the number and morphology of dendritic spines have been correlated to the developmental process as well as the pathophysiology of a number of neurodegenerative diseases. Due to the sheer scale of synaptic connectivity in the brain, work to date has merely scratched the surface in the study of normal spine function and pathology. This review will highlight traditional approaches to the imaging of dendritic spines and newer approaches made possible by advances in microscopy, protein engineering, and image analysis. The review will also describe recent work that is leading researchers toward the possibility of a systematic and comprehensive study of spine anatomy throughout the brain. PMID:22522468

  4. Oriented Markov random field based dendritic spine segmentation for fluorescence microscopy images.

    PubMed

    Cheng, Jie; Zhou, Xiaobo; Miller, Eric L; Alvarez, Veronica A; Sabatini, Bernardo L; Wong, Stephen T C

    2010-10-01

    Dendritic spines have been shown to be closely related to various functional properties of the neuron. Usually dendritic spines are manually labeled to analyze their morphological changes, which is very time-consuming and susceptible to operator bias, even with the assistance of computers. To deal with these issues, several methods have been recently proposed to automatically detect and measure the dendritic spines with little human interaction. However, problems such as degraded detection performance for images with larger pixel size (e.g. 0.125 μm/pixel instead of 0.08 μm/pixel) still exist in these methods. Moreover, the shapes of detected spines are also distorted. For example, the "necks" of some spines are missed. Here we present an oriented Markov random field (OMRF) based algorithm which improves spine detection as well as their geometric characterization. We begin with the identification of a region of interest (ROI) containing all the dendrites and spines to be analyzed. For this purpose, we introduce an adaptive procedure for identifying the image background. Next, the OMRF model is discussed within a statistical framework and the segmentation is solved as a maximum a posteriori estimation (MAP) problem, whose optimal solution is found by a knowledge-guided iterative conditional mode (KICM) algorithm. Compared with the existing algorithms, the proposed algorithm not only provides a more accurate representation of the spine shape, but also improves the detection performance by more than 50% with regard to reducing both the misses and false detection.

  5. Volumetric Image Guidance Using Carina vs Spine as Registration Landmarks for Conventionally Fractionated Lung Radiotherapy

    SciTech Connect

    Lavoie, Caroline; Higgins, Jane; Bissonnette, Jean-Pierre

    2012-12-01

    Purpose: To compare the relative accuracy of 2 image guided radiation therapy methods using carina vs spine as landmarks and then to identify which landmark is superior relative to tumor coverage. Methods and Materials: For 98 lung patients, 2596 daily image-guidance cone-beam computed tomography scans were analyzed. Tattoos were used for initial patient alignment; then, spine and carina registrations were performed independently. A separate analysis assessed the adequacy of gross tumor volume, internal target volume, and planning target volume coverage on cone-beam computed tomography using the initial, middle, and final fractions of radiation therapy. Coverage was recorded for primary tumormore » (T), nodes (N), and combined target (T+N). Three scenarios were compared: tattoos alignment, spine registration, and carina registration. Results: Spine and carina registrations identified setup errors {>=}5 mm in 35% and 46% of fractions, respectively. The mean vector difference between spine and carina matching had a magnitude of 3.3 mm. Spine and carina improved combined target coverage, compared with tattoos, in 50% and 34% (spine) to 54% and 46% (carina) of the first and final fractions, respectively. Carina matching showed greater combined target coverage in 17% and 23% of fractions for the first and final fractions, respectively; with spine matching, this was only observed in 4% (first) and 6% (final) of fractions. Carina matching provided superior nodes coverage at the end of radiation compared with spine matching (P=.0006), without compromising primary tumor coverage. Conclusion: Frequent patient setup errors occur in locally advanced lung cancer patients. Spine and carina registrations improved combined target coverage throughout the treatment course, but carina matching provided superior combined target coverage.« less

  6. The Use of Lumbar Spine Magnetic Resonance Imaging in Eastern China: Appropriateness and Related Factors

    PubMed Central

    Yu, Liedao; Wang, Xuanwei; Lin, Xiangjin; Wang, Yue

    2016-01-01

    Back pain is common and costly. While a general scene of back pain related practice in China remains unknown, there are signs of excessive use of lumbar spine magnetic resonance (MR). We retrospectively studied 3107 lumbar spine MRIs in Eastern China to investigate the appropriateness of lumbar spine MR use. Simple back pain is the most common chief complaint for ordering a lumbar MR study. Only 41.3% of lumbar spine MR studies identified some findings that may have potential clinical significance. Normal lumbar spine is the most common diagnosis (32.7%), followed by lumbar disc bulging and lumbar disc herniation. Walk difficulties, back injury and referred leg pain as chief complaints were associated with greater chance of detecting potentially clinically positive lumbar MR image findings, as compare with simple back pain. There was no difference in positive rates among orthopedic surgeon and specialists of other disciplines. Lumbar spine MR imaging was generally overused in Eastern China by various specialists, particularly at health assessment centers. For appropriate use of lumbar spine MR, orthopedic surgeons are no better than physicians of other disciplines. Professional training and clinical guidelines are needed to facilitate evidence-based back pain practice in China. PMID:26731106

  7. MIND Demons for MR-to-CT Deformable Image Registration In Image-Guided Spine Surgery

    PubMed Central

    Reaungamornrat, S.; De Silva, T.; Uneri, A.; Wolinsky, J.-P.; Khanna, A. J.; Kleinszig, G.; Vogt, S.; Prince, J. L.; Siewerdsen, J. H.

    2016-01-01

    Purpose Localization of target anatomy and critical structures defined in preoperative MR images can be achieved by means of multi-modality deformable registration to intraoperative CT. We propose a symmetric diffeomorphic deformable registration algorithm incorporating a modality independent neighborhood descriptor (MIND) and a robust Huber metric for MR-to-CT registration. Method The method, called MIND Demons, solves for the deformation field between two images by optimizing an energy functional that incorporates both the forward and inverse deformations, smoothness on the velocity fields and the diffeomorphisms, a modality-insensitive similarity function suitable to multi-modality images, and constraints on geodesics in Lagrangian coordinates. Direct optimization (without relying on an exponential map of stationary velocity fields used in conventional diffeomorphic Demons) is carried out using a Gauss-Newton method for fast convergence. Registration performance and sensitivity to registration parameters were analyzed in simulation, in phantom experiments, and clinical studies emulating application in image-guided spine surgery, and results were compared to conventional mutual information (MI) free-form deformation (FFD), local MI (LMI) FFD, and normalized MI (NMI) Demons. Result The method yielded sub-voxel invertibility (0.006 mm) and nonsingular spatial Jacobians with capability to preserve local orientation and topology. It demonstrated improved registration accuracy in comparison to the reference methods, with mean target registration error (TRE) of 1.5 mm compared to 10.9, 2.3, and 4.6 mm for MI FFD, LMI FFD, and NMI Demons methods, respectively. Validation in clinical studies demonstrated realistic deformation with sub-voxel TRE in cases of cervical, thoracic, and lumbar spine. Conclusions A modality-independent deformable registration method has been developed to estimate a viscoelastic diffeomorphic map between preoperative MR and intraoperative CT. The

  8. MIND Demons for MR-to-CT deformable image registration in image-guided spine surgery

    NASA Astrophysics Data System (ADS)

    Reaungamornrat, S.; De Silva, T.; Uneri, A.; Wolinsky, J.-P.; Khanna, A. J.; Kleinszig, G.; Vogt, S.; Prince, J. L.; Siewerdsen, J. H.

    2016-03-01

    Purpose: Localization of target anatomy and critical structures defined in preoperative MR images can be achieved by means of multi-modality deformable registration to intraoperative CT. We propose a symmetric diffeomorphic deformable registration algorithm incorporating a modality independent neighborhood descriptor (MIND) and a robust Huber metric for MR-to-CT registration. Method: The method, called MIND Demons, solves for the deformation field between two images by optimizing an energy functional that incorporates both the forward and inverse deformations, smoothness on the velocity fields and the diffeomorphisms, a modality-insensitive similarity function suitable to multi-modality images, and constraints on geodesics in Lagrangian coordinates. Direct optimization (without relying on an exponential map of stationary velocity fields used in conventional diffeomorphic Demons) is carried out using a Gauss-Newton method for fast convergence. Registration performance and sensitivity to registration parameters were analyzed in simulation, in phantom experiments, and clinical studies emulating application in image-guided spine surgery, and results were compared to conventional mutual information (MI) free-form deformation (FFD), local MI (LMI) FFD, and normalized MI (NMI) Demons. Result: The method yielded sub-voxel invertibility (0.006 mm) and nonsingular spatial Jacobians with capability to preserve local orientation and topology. It demonstrated improved registration accuracy in comparison to the reference methods, with mean target registration error (TRE) of 1.5 mm compared to 10.9, 2.3, and 4.6 mm for MI FFD, LMI FFD, and NMI Demons methods, respectively. Validation in clinical studies demonstrated realistic deformation with sub-voxel TRE in cases of cervical, thoracic, and lumbar spine. Conclusions: A modality-independent deformable registration method has been developed to estimate a

  9. MIND Demons for MR-to-CT Deformable Image Registration In Image-Guided Spine Surgery.

    PubMed

    Reaungamornrat, S; De Silva, T; Uneri, A; Wolinsky, J-P; Khanna, A J; Kleinszig, G; Vogt, S; Prince, J L; Siewerdsen, J H

    2016-02-27

    Localization of target anatomy and critical structures defined in preoperative MR images can be achieved by means of multi-modality deformable registration to intraoperative CT. We propose a symmetric diffeomorphic deformable registration algorithm incorporating a modality independent neighborhood descriptor (MIND) and a robust Huber metric for MR-to-CT registration. The method, called MIND Demons, solves for the deformation field between two images by optimizing an energy functional that incorporates both the forward and inverse deformations, smoothness on the velocity fields and the diffeomorphisms, a modality-insensitive similarity function suitable to multi-modality images, and constraints on geodesics in Lagrangian coordinates. Direct optimization (without relying on an exponential map of stationary velocity fields used in conventional diffeomorphic Demons) is carried out using a Gauss-Newton method for fast convergence. Registration performance and sensitivity to registration parameters were analyzed in simulation, in phantom experiments, and clinical studies emulating application in image-guided spine surgery, and results were compared to conventional mutual information (MI) free-form deformation (FFD), local MI (LMI) FFD, and normalized MI (NMI) Demons. The method yielded sub-voxel invertibility (0.006 mm) and nonsingular spatial Jacobians with capability to preserve local orientation and topology. It demonstrated improved registration accuracy in comparison to the reference methods, with mean target registration error (TRE) of 1.5 mm compared to 10.9, 2.3, and 4.6 mm for MI FFD, LMI FFD, and NMI Demons methods, respectively. Validation in clinical studies demonstrated realistic deformation with sub-voxel TRE in cases of cervical, thoracic, and lumbar spine. A modality-independent deformable registration method has been developed to estimate a viscoelastic diffeomorphic map between preoperative MR and intraoperative CT. The method yields registration

  10. Single-image hard-copy display of the spine utilizing digital radiography

    NASA Astrophysics Data System (ADS)

    Artz, Dorothy S.; Janchar, Timothy; Milzman, David; Freedman, Matthew T.; Mun, Seong K.

    1997-04-01

    Regions of the entire spine contain a wide latitude of tissue densities within the imaged field of view presenting a problem for adequate radiological evaluation. With screen/film technology, the optimal technique for one area of the radiograph is sub-optimal for another area. Computed radiography (CR) with its inherent wide dynamic range, has been shown to be better than screen/film for lateral cervical spine imaging, but limitations are still present with standard image processing. By utilizing a dynamic range control (DRC) algorithm based on unsharp masking and signal transformation prior to gradation and frequency processing within the CR system, more vertebral bodies can be seen on a single hard copy display of the lateral cervical, thoracic, and thoracolumbar examinations. Examinations of the trauma cross-table lateral cervical spine, lateral thoracic spine, and lateral thoracolumbar spine were collected on live patient using photostimulable storage phosphor plates, the Fuji FCR 9000 reader, and the Fuji AC-3 computed radiography reader. Two images were produced from a single exposure; one with standard image processing and the second image with the standard process and the additional DRC algorithm. Both sets were printed from a Fuji LP 414 laser printer. Two different DRC algorithms were applied depending on which portion of the spine was not well visualized. One algorithm increased optical density and the second algorithm decreased optical density. The resultant image pairs were then reviewed by a panel of radiologists. Images produced with the additional DRC algorithm demonstrated improved visualization of previously 'under exposed' and 'over exposed' regions within the same image. Where lung field had previously obscured bony detail of the lateral thoracolumbar spine due to 'over exposure,' the image with the DRC applied to decrease the optical density allowed for easy visualization of the entire area of interest. For areas of the lateral cervical spine

  11. Possibility Study of Scale Invariant Feature Transform (SIFT) Algorithm Application to Spine Magnetic Resonance Imaging

    PubMed Central

    Lee, Dong-Hoon; Lee, Do-Wan; Han, Bong-Soo

    2016-01-01

    The purpose of this study is an application of scale invariant feature transform (SIFT) algorithm to stitch the cervical-thoracic-lumbar (C-T-L) spine magnetic resonance (MR) images to provide a view of the entire spine in a single image. All MR images were acquired with fast spin echo (FSE) pulse sequence using two MR scanners (1.5 T and 3.0 T). The stitching procedures for each part of spine MR image were performed and implemented on a graphic user interface (GUI) configuration. Moreover, the stitching process is performed in two categories; manual point-to-point (mPTP) selection that performed by user specified corresponding matching points, and automated point-to-point (aPTP) selection that performed by SIFT algorithm. The stitched images using SIFT algorithm showed fine registered results and quantitatively acquired values also indicated little errors compared with commercially mounted stitching algorithm in MRI systems. Our study presented a preliminary validation of the SIFT algorithm application to MRI spine images, and the results indicated that the proposed approach can be performed well for the improvement of diagnosis. We believe that our approach can be helpful for the clinical application and extension of other medical imaging modalities for image stitching. PMID:27064404

  12. Detection of degenerative change in lateral projection cervical spine x-ray images

    NASA Astrophysics Data System (ADS)

    Jebri, Beyrem; Phillips, Michael; Knapp, Karen; Appelboam, Andy; Reuben, Adam; Slabaugh, Greg

    2015-03-01

    Degenerative changes to the cervical spine can be accompanied by neck pain, which can result from narrowing of the intervertebral disc space and growth of osteophytes. In a lateral x-ray image of the cervical spine, degenerative changes are characterized by vertebral bodies that have indistinct boundaries and limited spacing between vertebrae. In this paper, we present a machine learning approach to detect and localize degenerative changes in lateral x-ray images of the cervical spine. Starting from a user-supplied set of points in the center of each vertebral body, we fit a central spline, from which a region of interest is extracted and image features are computed. A Random Forest classifier labels regions as degenerative change or normal. Leave-one-out cross-validation studies performed on a dataset of 103 patients demonstrates performance of above 95% accuracy.

  13. Imaging evaluation of traumatic thoracolumbar spine injuries: Radiological review

    PubMed Central

    Gamanagatti, Shivanand; Rathinam, Deepak; Rangarajan, Krithika; Kumar, Atin; Farooque, Kamran; Sharma, Vijay

    2015-01-01

    Spine fractures account for a large portion of musculoskeletal injuries worldwide. A classification of spine fractures is necessary in order to develop a common language for treatment indications and outcomes. Several classification systems have been developed based on injury anatomy or mechanisms of action, but they have demonstrated poor reliability, have yielded little prognostic information, and have not been widely used. For this reason, the Arbeitsgemeinschaftfür Osteosynthesefragen (AO) committee has classified thorocolumbar spine injuries based on the pathomorphological criteria into3 types (A: Compression; B: Distraction; C: Axial torque and rotational deformity). Each of these types is further divided into 3 groups and 3 subgroups reflecting progressive scale of morphological damage and the degree of instability. Because of its highly detailed sub classifications, the AO system has shown limited interobserver variability. It is similar to its predecessors in that it does not incorporate the patient’s neurologic status.The need for a reliable, reproducible, clinically relevant, prognostic classification system with an optimal balance of ease of use and detail of injury description contributed to the development of a new classification system, the thoracolumbar injury classification and severity score (TLICS). The TLICS defines injury based on three clinical characteristics: injury morphology, integrity of the posterior ligamentous complex, and neurologic status of the patient. The severity score offers prognostic information and is helpful in decision making about surgical vs nonsurgical management. PMID:26435776

  14. High resolution magnetic resonance imaging of the calcaneus: age-related changes in trabecular structure and comparison with dual X-ray absorptiometry measurements

    NASA Technical Reports Server (NTRS)

    Ouyang, X.; Selby, K.; Lang, P.; Engelke, K.; Klifa, C.; Fan, B.; Zucconi, F.; Hottya, G.; Chen, M.; Majumdar, S.; hide

    1997-01-01

    A high-resolution magnetic resonance imaging (MRI) protocol, together with specialized image processing techniques, was applied to the quantitative measurement of age-related changes in calcaneal trabecular structure. The reproducibility of the technique was assessed and the annual rates of change for several trabecular structure parameters were measured. The MR-derived trabecular parameters were compared with calcaneal bone mineral density (BMD), measured by dual X-ray absorptiometry (DXA) in the same subjects. Sagittal MR images were acquired at 1.5 T in 23 healthy women (mean age: 49.3 +/- 16.6 [SD]), using a three-dimensional gradient echo sequence. Image analysis procedures included internal gray-scale calibration, bone and marrow segmentation, and run-length methods. Three trabecular structure parameters, apparent bone volume (ABV/TV), intercept thickness (I.Th), and intercept separation (I.Sp) were calculated from the MR images. The short- and long-term precision errors (mean %CV) of these measured parameters were in the ranges 1-2% and 3-6%, respectively. Linear regression of the trabecular structure parameters vs. age showed significant correlation: ABV/TV (r2 = 33.7%, P < 0.0037), I.Th (r2 = 26.6%, P < 0.0118), I.Sp (r2 = 28.9%, P < 0.0081). These trends with age were also expressed as annual rates of change: ABV/TV (-0.52%/year), I.Th (-0.33%/year), and I.Sp (0.59%/year). Linear regression analysis also showed significant correlation between the MR-derived trabecular structure parameters and calcaneal BMD values. Although a larger group of subjects is needed to better define the age-related changes in trabecular structure parameters and their relation to BMD, these preliminary results demonstrate that high-resolution MRI may potentially be useful for the quantitative assessment of trabecular structure.

  15. Comparison of image quality and radiation exposure from C-arm fluoroscopes when used for imaging the spine.

    PubMed

    Prasarn, Mark L; Coyne, Ellen; Schreck, Michael; Rodgers, Jamie D; Rechtine, Glenn R

    2013-07-15

    Cadaveric imaging study. We sought to compare the fluoroscopic images produced by 4 different fluoroscopes for image quality and radiation exposure when used for imaging the spine. There are no previous published studies comparing mobile C-arm machines commonly used in clinical practice for imaging the spine. Anterior-posterior and lateral images of the cervical, thoracic, and lumbar spine were obtained from a cadaver placed supine on a radiolucent table. The fluoroscopy units used for the study included (1) GE OEC 9900 Elite (2010 model; General Electric Healthcare, Waukesha, WI), (2) Philips BV Pulsera (2009 model; Philips Healthcare, Andover, MA), (3) Philips BV Pulsera (2010 model; Philips Healthcare, Andover, MA), and (4) Siemens Arcadis Avantic (2010 model; Siemens Medical Solutions, Malvern, PA). The images were then downloaded, placed into a randomizer program, and evaluated by a group of spine surgeons and neuroradiologists independently. The reviewers, who were blinded to the fluoroscope the images were from, ranked them from best to worst using a numeric system. In addition, the images were rated according to a quality scale from 1 to 5, with 1 representing the best image quality. The radiation exposure level for the fluoroscopy units was also compared and was based on energy emission. According to the mean values for rank, the following order of best to worst was observed: (1) GE OEC > (2) Philips 2010 > (3) Philips 2009 > (4) Siemans. The exact same order was found when examining the image quality ratings. When comparing the radiation exposure level difference, it was observed that the OEC was the lowest, and there was a minimum 30% decrease in energy emission from the OEC versus the other C-arms studied. This is the first time that the spine image quality and radiation exposure of commonly used C-arm machines have been compared. The OEC was ranked the best, produced the best quality images, and had the least amount of radiation.

  16. Melorheostosis involving the cervical and upper thoracic spine: radiographic, CT, and MR imaging findings.

    PubMed

    Motimaya, A M; Meyers, S P

    2006-01-01

    Melorheostosis, an uncommon mesenchymal dysplasia, rarely affects the axial skeleton. We describe the imaging findings of melorheostosis involving the cervical and upper thoracic spine. Radiographs and CT showed unilateral well-marginated undulating zones of cortical hyperostosis involving multiple vertebrae that were contiguous with a coalescent ossified right paravertebral mass. MR imaging showed zones of signal intensity void on all pulse sequences without contrast enhancement. Conservative management was elected because of lack of interval clinical and imaging changes for 8 years.

  17. Group-wise feature-based registration of CT and ultrasound images of spine

    NASA Astrophysics Data System (ADS)

    Rasoulian, Abtin; Mousavi, Parvin; Hedjazi Moghari, Mehdi; Foroughi, Pezhman; Abolmaesumi, Purang

    2010-02-01

    Registration of pre-operative CT and freehand intra-operative ultrasound of lumbar spine could aid surgeons in the spinal needle injection which is a common procedure for pain management. Patients are always in a supine position during the CT scan, and in the prone or sitting position during the intervention. This leads to a difference in the spinal curvature between the two imaging modalities, which means a single rigid registration cannot be used for all of the lumbar vertebrae. In this work, a method for group-wise registration of pre-operative CT and intra-operative freehand 2-D ultrasound images of the lumbar spine is presented. The approach utilizes a pointbased registration technique based on the unscented Kalman filter, taking as input segmented vertebrae surfaces in both CT and ultrasound data. Ultrasound images are automatically segmented using a dynamic programming approach, while the CT images are semi-automatically segmented using thresholding. Since the curvature of the spine is different between the pre-operative and the intra-operative data, the registration approach is designed to simultaneously align individual groups of points segmented from each vertebra in the two imaging modalities. A biomechanical model is used to constrain the vertebrae transformation parameters during the registration and to ensure convergence. The mean target registration error achieved for individual vertebrae on five spine phantoms generated from CT data of patients, is 2.47 mm with standard deviation of 1.14 mm.

  18. Prediction of appendicular skeletal and fat mass in children: excellent concordance of dual-energy X-ray absorptiometry and magnetic resonance imaging.

    PubMed

    Bridge, Pascale; Pocock, Nicholas A; Nguyen, Tuan; Munns, Craig; Cowell, Christopher T; Thompson, Martin W

    2009-09-01

    Body composition studies in children have great potential to help understand the aetiology and evolution of acute and chronic. diseases. To validate appendicular lean soft tissue mass (LSTM) and fat mass (FM) measured using dual energy X-ray absorptiometry (DXA), with magnetic resonance imaging (MRI) as the reference standard, in healthy peri-pubertal adolescents. Peri-pubertal Caucasian children (n = 74) aged 11-14 years were evaluated. DXA LSTM and FM of the mid third femur were measured and skeletal muscle mass (SM) and FM of the same region were measured on the same day by MRI. There was a strong correlation between MRI SM and DXA LSTM (r2 = 0.98, index of concordance [C] = 0.91). DXA estimation of LSTM exceeded MRI SM by a mean of 189 g, from 6-371 g (p < 0.0001). The discordance between DXA and MRI significantly increased with the absolute value (r = 0.27; p = 0.024). FM was highly correlated (r = 0.98) with a high index of concordance (C = 0.97). This study validates the use of DXA in LSTM measurement in children, confirming its potential in clinical and research roles in paediatric diseases affecting and related to body composition.

  19. Investigation of the Entrance Surface Dose and Dose to Different Organs in Lumbar Spine Imaging

    PubMed Central

    Sina, S; Zeinali, B; Karimipoorfard, M; Lotfalizadeh, F; Sadeghi, M; Zamani, E; Faghihi, R

    2014-01-01

    Background: Dose assessment using proper dosimeters is especially important in radiation protection optimization and imaging justification in diagnostic radiology. Objective: The aim of this study is to obtain the Entrance Skin Dose (ESD) of patients undergoing lumbar spine imaging using two thermoluminescence dosimeters TLD-100 (LiF: Mg, Ti) and GR-200 (LiF: Mg, Cu, P) and also to obtain the absorbed dose to different organs in lumbar spine imaging with several views. Methods: To measure the ESD values of the patients undergoing lumbar spine imaging, the two TLD types were put on their skin surface. The ESD values for different views of lumbar spine imaging were also measured by putting the TLDs at the surface of the Rando phantom. Several TLD chips were inserted inside different organs of Rando phantom to measure the absorbed dose to different organs in lumbar spine imaging. Results: The results indicate that there is a close agreement between the results of the two dosimeters. Based on the results of this experiment, the ESD dose of the 16 patients included in this study varied between 2.71 mGy and 26.29 mGy with the average of 11.89 mGy for TLD-100, and between 2.55 mGy and 27.41 mGy with the average of 12.32 mGy for GR-200 measurements. The ESDs obtained by putting the two types of TLDs at the surface of Rando phantom are in close agreement. Conclusion: According to the results, the GR200 has greater sensitivity than the TLD-100. PMID:25599058

  20. Ultrasound Imaging of Spine: State of the Art and Utility for Space Flight

    NASA Technical Reports Server (NTRS)

    Sargsyan, Ashot E.; Bouffard, Antonio J.; Garcia, Kathleen; Hamilton, Douglas R.; Van Holsbeeck, Marnix; Ebert, Douglas J. W.; Dulchavsky, Scott A.

    2010-01-01

    Introduction: Ultrasound imaging (sonography) has been increasingly used for both primary diagnosis and monitoring of musculoskeletal injury, including fractures. In certain injuries, sonography has been shown to equal or surpass Magnetic Resonance Imaging in accuracy. Long-term exposure to reduced gravity may be expected to cause physiological and anatomical changes of the musculoskeletal system, which are not fully described or understood. In a limited-resource environment like space flight, sonography will likely remain the only imaging modality; therefore, further attention to its potential is warranted, including its ability to image anatomical deviations as well as irregularities of vertebrae and the spinal column. Methods: A thorough review of literature was conducted on the subject. A multipurpose ultrasound system was used to identify specific vertebrae, intervertebral disks, and other structures of the cervical spine in healthy volunteers, selected to represent various age, gender, and Body Mass Index (BMI) groups. Sonographic views were sought that would parallel radiographic views and signs used in the diagnosis of cervical spine injuries. Results: While using widely accepted radiographic signs of cervical spine injury, this sonographic protocol development effort resulted in successful identification of scanning planes and imaging protocols that could serve as alternatives for radiography. Some of these views are also applicable to diagnosing degenerative disk and bone disease, and other non-traumatic spine pathology. Strong, preliminary correlation has been demonstrated in a number of clinical cases between sonography and other imaging modalities. Conclusion: In the absence of radiography, sonography can be used to diagnose or rule out certain common types of cervical spine conditions including injury. Clinical validation of the findings appears to be realistic and would facilitate establishment of new sonographic protocols for special environments

  1. Segmentation and feature extraction of cervical spine x-ray images

    NASA Astrophysics Data System (ADS)

    Long, L. Rodney; Thoma, George R.

    1999-05-01

    As part of an R&D project in mixed text/image database design, the National Library of Medicine has archived a collection of 17,000 digitized x-ray images of the cervical and lumbar spine which were collected as part of the second National Health and Nutrition Examination Survey (NHANES II). To make this image data available and usable to a wide audience, we are investigating techniques for indexing the image content by automated or semi-automated means. Indexing of the images by features of interest to researchers in spine disease and structure requires effective segmentation of the vertebral anatomy. This paper describes work in progress toward this segmentation of the cervical spine images into anatomical components of interest, including anatomical landmarks for vertebral location, and segmentation and identification of individual vertebrae. Our work includes developing a reliable method for automatically fixing an anatomy-based coordinate system in the images, and work to adaptively threshold the images, using methods previously applied by researchers in cardioangiography. We describe the motivation for our work and present our current results in both areas.

  2. Cervical spine imaging for young children with inflicted trauma: Expanding the injury pattern.

    PubMed

    Baerg, Joanne; Thirumoorthi, Arul; Vannix, Rosemary; Taha, Asma; Young, Amy; Zouros, Alexander

    2017-05-01

    The purpose of this study was to document the incidence and pattern of cervical spine (c-spine) injuries in children below 36months with inflicted trauma. An IRB approved, prospective cohort study was performed between July 2011 and January 2016. Inclusion criteria were: age below 36months, loss of consciousness after inflicted trauma, and one initial head computed tomography finding: a subdural, intraventricular, intraparenchymal, subarachnoid hemorrhage, diffuse axonal injury, hypoxic injury, or cerebral edema. A protocol of brain and neck magnetic resonance imaging and angiography was obtained within 48h. Variables were compared by t-test and Fisher-exact test. There were 53 children (median age: five months; range: 1-35months), 38 males (71.7%), of which seven died (13.2%). C-spine injury was identified in 8 (15.1%): ligamentous injury (2), vertebral artery shear injury (1), atlantooccipital dissociation (AOD) (1), cord injury with cord epidural hematoma (2), and isolated cord epidural hematoma (2). Retinal hemorrhages (p=0.02), shaking (p=0.04), lower Glasgow coma score (GCS) (p=0.01), brain infarcts (p=0.01), and hypoxic/ischemic injury (p=0.01) were associated with c-spine injury. One with AOD died. Six had significant disability. For small children with inflicted trauma, the c-spine injury incidence is 15.1%. The injury pattern includes retinal hemorrhages, shaking, lower GCS, and brain injury. Evaluation of shaken infants should include c-spine imaging. Level 2 A- This is a prospective cohort study with complete follow-up to hospital discharge or death. In all cases, inflicted trauma was confirmed. Owing to the nature of child abuse, the precise time of injury is not known. All children underwent a strict imaging protocol on arrival to hospital that was supervised on a prospective basis. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Magnetic resonance imaging of the brain and spine

    SciTech Connect

    Atlas, S.W.

    This book will be of use to neuroradiologists, neurologists, neurosurgeons, and all other clinicians who interact to discuss the results of MRI in patients with neurologic disease. It is hoped that this book will aid in this interaction by adding insight into the interpretation of scans and by promulgating a common language. Neuroradiologists and others who interpret MRI of the brain and spine will benefit from the detailed discussions concerning the basis of signal intensity derangements, whether on the fundamental level (i.e., physical or biochemical) or at the level of correlations with clinical and neuropathological findings. It is anticipated thatmore » all neuroscience personnel interested in clinical disease states and in neurological research will be able to utilize this text as a starting point and reference for proposed work utilizing MRI.« less

  4. Reduced Field of View Diffusion-Weighted Imaging in the Evaluation of Congenital Spine Malformations.

    PubMed

    Radhakrishnan, Rupa; Betts, Aaron M; Care, Marguerite M; Serai, Suraj; Zhang, Bin; Jones, Blaise V

    2016-05-01

    Reduced field of view diffusion-weighted imaging (rFOV DWI) is a more recently described technique in the evaluation of spine pathology. In adults, this technique has been shown to increase clinician confidence in identification of diffusion restricting lesions. In this study, we evaluate the image quality and diagnostic confidence of the rFOV DWI technique in pediatric spine MRI. We included patients with MRI of the lumbar spine for suspected congenital abnormalities who had conventional SS-EPI (single shot echo planar imaging) with full field of view (fFOV) and rFOV DWI performed. Images were graded for image quality and observer confidence for detection of lesions with reduced diffusion. Position of the conus and L3 vertebral body measurements were recorded. Comparisons were made between the fFOV and rFOV scores. Fifty children (30 girls, 20 boys) were included (median 3.6 years). Compared to the fFOV images, the rFOV images scored higher in image quality (P < 0.0001) and for confidence in detecting lesions with reduced diffusion (P < 0.0001). The average spread of identified conus position was smaller for in rFOV compared to fFOV (P = 0.0042). There was no significant difference in the L3 vertebral body measurements between the two methods. In rFOV, the anterior aspects of the vertebral bodies were excluded in a few studies due to narrow FOV. rFOV DWI of the lumbar spine in the pediatric population has qualitatively improved image quality and observer confidence for lesion detection when compared to conventional fFOV SS-EPI DWI. Copyright © 2015 by the American Society of Neuroimaging.

  5. Comparison of two bioelectrical impedance analysis devices with dual energy X-ray absorptiometry and magnetic resonance imaging in the estimation of body composition.

    PubMed

    Wang, Ji-Guang; Zhang, Yi; Chen, Han-E; Li, Yan; Cheng, Xiao-Guang; Xu, Li; Guo, Zhe; Zhao, Xing-Shan; Sato, Tetsuya; Cao, Qi-Yun; Chen, Ke-Min; Li, Biao

    2013-01-01

    We compared a 4-limb bioelectrical impedance analysis (BIA) system, HBF 359 (Omron), and a 2-limb foot-to-foot device, BC 532 (Tanita), with the standard dual energy X-ray absorptiometry (DXA) and magnetic resonance imaging (MRI) methods for the measurement of body fat percentage (BF), skeletal muscle mass percentage (SMM, or fat-free mass [FFM] for BC 532), and visceral fat level (VF). Body composition was measured in 200 healthy volunteers (100 men and 100 women, mean age 48 years) by HBF 359 and BC 532 and by DXA and MRI. The agreement was assessed by correlation analysis and paired t-test. The correlation coefficients between BIA and DXA or MRI ranged from 0.71 to 0.89 for BF, SMM, and VF by HBF 359 and from 0.77 to 0.90 for BF, FFM, and VF by BC 532 in all subjects and in men and women separately (p < 0.001 for all). Compared with DXA, HBF 359 significantly (p < 0.001) underestimated BF by -5.8% in men and -9.6% in women. Compared with MRI, the corresponding underestimatons (negative) or overestimations (positive) by HBF 359 in men and women were, respectively, +1.9% (p = 0.02) and +1.7% (p = 0.10) for SMM, and +13.3% (p < 0.001) and -8.5% (p = 0.006), for VF. The corresponding values by BC 532 in men and women were -10.7 and -6.2% for BF, -1.4 and -2.5% for FFM, and +20.4 and -18.0% for VF. The BIA devices are accurate in the estimation of body composition, especially skeletal muscle mass or FFM.

  6. Comparison of dual-energy X-ray absorptiometry and magnetic resonance imaging-measured adipose tissue depots in HIV-infected and control subjects.

    PubMed

    Scherzer, Rebecca; Shen, Wei; Bacchetti, Peter; Kotler, Donald; Lewis, Cora E; Shlipak, Michael G; Punyanitya, Mark; Heymsfield, Steven B; Grunfeld, Carl

    2008-10-01

    Studies in persons without HIV infection have compared adipose tissue measured by dual-energy X-ray absorptiometry (DXA) and magnetic resonance imaging (MRI), but no such study has been conducted in HIV-infected (HIV+) subjects, who have a high prevalence of regional fat loss. We compared DXA- with MRI-measured trunk, leg, arm, and total fat in HIV+ and control subjects. A cross-sectional analysis was conducted in 877 HIV+ subjects and 260 control subjects in FRAM (Study of Fat Redistribution and Metabolic Change in HIV Infection), stratified by sex and HIV status. Univariate associations of DXA with MRI were strongest for total and trunk fat (r > or = 0.92) and slightly weaker for leg (r > or = 0.87) and arm (r > or = 0.71) fat. The average estimated limb fat was substantially greater for DXA than for MRI for HIV+ and control men and women (all P < 0.0001). Less of a difference was observed in trunk fat measured by DXA and MRI, but the difference was still statistically significant (P < 0.0001). Bland-Altman plots showed increasing differences and variability. Greater average limb fat in control and HIV+ subjects (both P < 0.0001) was associated with greater differences between DXA and MRI measurements. Because the control subjects had more limb fat than did the HIV+ subjects, greater amounts of fat were measured by DXA than by MRI when control subjects were compared with HIV+ subjects. More HIV+ subjects had leg fat in the bottom decile of the control subjects by DXA than by MRI (P < 0.0001). Although DXA- and MRI-measured adipose tissue depots correlate strongly in HIV+ and control subjects, differences increase as average fat increases, particularly for limb fat. DXA may estimate a higher prevalence of peripheral lipoatrophy than does MRI in HIV+ subjects.

  7. Comparison of gross body fat-water magnetic resonance imaging at 3 Tesla to dual-energy X-ray absorptiometry in obese women.

    PubMed

    Silver, Heidi J; Niswender, Kevin D; Kullberg, Joel; Berglund, Johan; Johansson, Lars; Bruvold, Morten; Avison, Malcolm J; Welch, E Brian

    2013-04-01

    Improved understanding of how depot-specific adipose tissue mass predisposes to obesity-related comorbidities could yield new insights into the pathogenesis and treatment of obesity as well as metabolic benefits of weight loss. We hypothesized that three-dimensional (3D) contiguous "fat-water" MR imaging (FWMRI) covering the majority of a whole-body field of view (FOV) acquired at 3 Tesla (3T) and coupled with automated segmentation and quantification of amount, type, and distribution of adipose and lean soft tissue would show great promise in body composition methodology. Precision of adipose and lean soft tissue measurements in body and trunk regions were assessed for 3T FWMRI and compared to dual-energy X-ray absorptiometry (DXA). Anthropometric, FWMRI, and DXA measurements were obtained in 12 women with BMI 30-39.9 kg/m(2) . Test-retest results found coefficients of variation (CV) for FWMRI that were all under 3%: gross body adipose tissue (GBAT) 0.80%, total trunk adipose tissue (TTAT) 2.08%, visceral adipose tissue (VAT) 2.62%, subcutaneous adipose tissue (SAT) 2.11%, gross body lean soft tissue (GBLST) 0.60%, and total trunk lean soft tissue (TTLST) 2.43%. Concordance correlation coefficients between FWMRI and DXA were 0.978, 0.802, 0.629, and 0.400 for GBAT, TTAT, GBLST, and TTLST, respectively. While Bland-Altman plots demonstrated agreement between FWMRI and DXA for GBAT and TTAT, a negative bias existed for GBLST and TTLST measurements. Differences may be explained by the FWMRI FOV length and potential for DXA to overestimate lean soft tissue. While more development is necessary, the described 3T FWMRI method combined with fully-automated segmentation is fast (<30-min total scan and post-processing time), noninvasive, repeatable, and cost-effective. Copyright © 2012 The Obesity Society.

  8. Prediction of android and gynoid body adiposity via a three-dimensional stereovision body imaging system and dual-energy x-ray absorptiometry

    PubMed Central

    Lee, Jane J.; Freeland-Graves, Jeanne H.; Pepper, M. Reese; Stanforth, Philip R.; Xu, Bugao

    2017-01-01

    Objective Current methods for measuring regional body fat are expensive and inconvenient compared to the relative cost-effectiveness and ease-of-use of a stereovision body imaging (SBI) system. The primary goal of this research is to develop prediction models for android and gynoid fat by body measurements assessed via SBI and dual-energy x-ray absorptiometry (DXA). Subsequently, mathematical equations for prediction of total and regional (trunk, leg) body adiposity were established via parameters measured by SBI and DXA. Methods A total of 121 participants were randomly assigned into primary and cross-validation groups. Body measurements were obtained via traditional anthropometrics, SBI, and DXA. Multiple regression analysis was conducted to develop mathematical equations by demographics and SBI assessed body measurements as independent variables and body adiposity (fat mass and percent fat) as dependent variables. The validity of the prediction models was evaluated by a split sample method and Bland-Altman analysis. Results The R2 of the prediction equations for fat mass and percent body fat were 93.2% and 76.4% for android, and 91.4% and 66.5% for gynoid, respectively. The limits of agreement for the fat mass and percent fat were − 0.06 ± 0.87 kg and − 0.11 ± 1.97 % for android and − 0.04 ± 1.58 kg and − 0.19 ± 4.27 % for gynoid. Prediction values for fat mass and percent fat were 94.6% and 88.9% for total body, 93.9% and 71.0% for trunk, and 92.4% and 64.1% for leg, respectively. Conclusions The three-dimensional (3D) SBI produces reliable parameters that can predict android and gynoid, as well as total and regional (trunk, leg) fat mass. PMID:25915106

  9. Prediction of Android and Gynoid Body Adiposity via a Three-dimensional Stereovision Body Imaging System and Dual-Energy X-ray Absorptiometry.

    PubMed

    Lee, Jane J; Freeland-Graves, Jeanne H; Pepper, M Reese; Stanforth, Philip R; Xu, Bugao

    2015-01-01

    Current methods for measuring regional body fat are expensive and inconvenient compared to the relative cost-effectiveness and ease of use of a stereovision body imaging (SBI) system. The primary goal of this research is to develop prediction models for android and gynoid fat by body measurements assessed via SBI and dual-energy x-ray absorptiometry (DXA). Subsequently, mathematical equations for prediction of total and regional (trunk, leg) body adiposity were established via parameters measured by SBI and DXA. A total of 121 participants were randomly assigned into primary and cross-validation groups. Body measurements were obtained via traditional anthropometrics, SBI, and DXA. Multiple regression analysis was conducted to develop mathematical equations by demographics and SBI assessed body measurements as independent variables and body adiposity (fat mass and percentage fat) as dependent variables. The validity of the prediction models was evaluated by a split sample method and Bland-Altman analysis. The R(2) of the prediction equations for fat mass and percentage body fat were 93.2% and 76.4% for android and 91.4% and 66.5% for gynoid, respectively. The limits of agreement for the fat mass and percentage fat were -0.06 ± 0.87 kg and -0.11% ± 1.97% for android and -0.04 ± 1.58 kg and -0.19% ± 4.27% for gynoid. Prediction values for fat mass and percentage fat were 94.6% and 88.9% for total body, 93.9% and 71.0% for trunk, and 92.4% and 64.1% for leg, respectively. The three-dimensional (3D) SBI produces reliable parameters that can predict android and gynoid as well as total and regional (trunk, leg) fat mass.

  10. Surveillance imaging in children with malignant CNS tumors: low yield of spine MRI.

    PubMed

    Perreault, Sébastien; Lober, Robert M; Carret, Anne-Sophie; Zhang, Guohua; Hershon, Linda; Décarie, Jean-Claude; Vogel, Hannes; Yeom, Kristen W; Fisher, Paul G; Partap, Sonia

    2014-02-01

    Magnetic resonance imaging (MRI) is routinely obtained in patients with central nervous system (CNS) tumors, but few studies have been conducted to evaluate this practice. We assessed the benefits of surveillance MRI and more specifically spine MRI in a contemporary cohort. We evaluated MRI results of children diagnosed with CNS tumors from January 2000 to December 2011. Children with at least one surveillance MRI following the diagnosis of medulloblastoma (MB), atypical teratoid rhabdoid tumor (ATRT), pineoblastoma (PB), supratentorial primitive neuroectodermal tumor, supratentorial high-grade glioma (World Health Organization grade III-IV), CNS germ cell tumors or ependymoma were included. A total of 2,707 brain and 1,280 spine MRI scans were obtained in 258 patients. 97% of all relapses occurred in the brain and 3% were isolated to the spine. Relapse was identified in 226 (8%) brain and 48 (4%) spine MRI scans. The overall rate of detecting isolated spinal relapse was 9/1,000 and 7/1,000 for MB patients. MRI performed for PB showed the highest rate for detecting isolated spinal recurrence with 49/1,000. No initial isolated spinal relapse was identified in patients with glioma, supratentorial primitive neuroectodermal tumor and ATRT. Isolated spinal recurrences are infrequent in children with malignant CNS tumors and the yield of spine MRI is very low. Tailoring surveillance spine MRI to patients with higher spinal relapse risk such as PB, MB with metastatic disease and within 3 years of diagnosis could improve allocation of resources without compromising patient care.

  11. Probabilistic registration of an unbiased statistical shape model to ultrasound images of the spine

    NASA Astrophysics Data System (ADS)

    Rasoulian, Abtin; Rohling, Robert N.; Abolmaesumi, Purang

    2012-02-01

    The placement of an epidural needle is among the most difficult regional anesthetic techniques. Ultrasound has been proposed to improve success of placement. However, it has not become the standard-of-care because of limitations in the depictions and interpretation of the key anatomical features. We propose to augment the ultrasound images with a registered statistical shape model of the spine to aid interpretation. The model is created with a novel deformable group-wise registration method which utilizes a probabilistic approach to register groups of point sets. The method is compared to a volume-based model building technique and it demonstrates better generalization and compactness. We instantiate and register the shape model to a spine surface probability map extracted from the ultrasound images. Validation is performed on human subjects. The achieved registration accuracy (2-4 mm) is sufficient to guide the choice of puncture site and trajectory of an epidural needle.

  12. Measurement of segmental lumbar spine flexion and extension using ultrasound imaging.

    PubMed

    Chleboun, Gary S; Amway, Matthew J; Hill, Jesse G; Root, Kara J; Murray, Hugh C; Sergeev, Alexander V

    2012-10-01

    Clinical measurement, technical note. To describe a technique to measure interspinous process distance using ultrasound (US) imaging, to assess the reliability of the technique, and to compare the US imaging measurements to magnetic resonance imaging (MRI) measurements in 3 different positions of the lumbar spine. Segmental spinal motion has been assessed using various imaging techniques, as well as surgically inserted pins. However, some imaging techniques are costly (MRI) and some require ionizing radiation (radiographs and fluoroscopy), and surgical procedures have limited use because of the invasive nature of the technique. Therefore, it is important to have an easily accessible and inexpensive technique for measuring lumbar segmental motion to more fully understand spine motion in vivo, to evaluate the changes that occur with various interventions, and to be able to accurately relate the changes in symptoms to changes in motion of individual vertebral segments. Six asymptomatic subjects participated. The distance between spinous processes at each lumbar segment (L1-2, L2-3, L3-4, L4-5) was measured digitally using MRI and US imaging. The interspinous distance was measured with subjects supine and the lumbar spine in 3 different positions (resting, lumbar flexion, and lumbar extension) for both MRI and US imaging. The differences in distance from neutral to extension, neutral to flexion, and extension to flexion were calculated. The measurement methods had excellent reliability for US imaging (intraclass correlation coefficient [ICC3,3] = 0.94; 95% confidence interval: 0.85, 0.97) and MRI (ICC3,3 = 0.98; 95% confidence interval: 0.95, 0.99). The distance measured was similar between US imaging and MRI (P>.05), except at L3-4 flexion-extension (P = .003). On average, the MRI measurements were 1.3 mm greater than the US imaging measurements. This study describes a new method for the measurement of lumbar spine segmental flexion and extension motion using US

  13. Sticking our neck out: is magnetic resonance imaging needed to clear an obtunded patient's cervical spine?

    PubMed

    Satahoo, Shevonne S; Davis, James S; Garcia, George D; Alsafran, Salman; Pandya, Reeni K; Richie, Cheryl D; Habib, Fahim; Rivas, Luis; Namias, Nicholas; Schulman, Carl I

    2014-03-01

    Evaluating the cervical spine in the obtunded trauma patient is a subject fraught with controversy. Some authors assert that a negative computed tomography (CT) scan is sufficient. Others argue that CT alone misses occult unstable injuries, and magnetic resonance imaging (MRI) will alter treatment. This study examines the data in an urban, county trauma center to determine if a negative cervical spine CT scan is sufficient to clear the obtunded trauma patient. Records of all consecutive patients admitted to a level 1 trauma center from January 2000 to December 2011 were retrospectively analyzed. Patients directly admitted to the intensive care unit with a Glasgow Coma Scale score ≤13, contemporaneous CT and MRI, and a negative CT reading were included. The results of the cervical spine MRI were analyzed. A total of 309 patients had both CT and MRI, 107 (35%) of whom had negative CTs. Mean time between CT and MRI was 16 d. Of those patients, seven (7%) had positive acute traumatic findings on MRI. Findings included ligamentous injury, subluxation, and fracture. However, only two of these patients required surgical intervention. None had unstable injuries. In the obtunded trauma patient with a negative cervical spine CT, obtaining an MRI does not appear to significantly alter management, and no unstable injuries were missed on CT scan. This should be taken into consideration given the current efforts at cost-containment in the health care system. It is one of the larger studies published to date. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Use of diagnostic imaging in the emergency department for cervical spine injuries in Kingston, Ontario.

    PubMed

    Pickett, William; Kukaswadia, Atif; Thompson, Wendy; Frechette, Mylene; McFaull, Steven; Dowdall, Hilary; Brison, Robert J

    2014-01-01

    This study assessed the use and clinical yield of diagnostic imaging (radiography, computed tomography, and medical resonance imaging) ordered to assist in the diagnosis of acute neck injuries presenting to emergency departments (EDs) in Kingston, Ontario, from 2002-2003 to 2009-2010. Acute neck injury cases were identified using records from the Kingston sites of the Canadian National Ambulatory Care Reporting System. Use of radiography was analyzed over time and related to proportions of cases diagnosed with clinically significant cervical spine injuries. A total of 4,712 neck injury cases were identified. Proportions of cases referred for diagnostic imaging to the neck varied significantly over time, from 30.4% in 2002-2003 to 37.6% in 2009-2010 (ptrend  =  0.02). The percentage of total cases that were positive for clinically significant cervical spine injury ("clinical yield") also varied from a low of 5.8% in 2005-2006 to 9.2% in 2008-2009 (ptrend  =  0.04), although the clinical yield of neck-imaged cases did not increase across the study years (ptrend  =  0.23). Increased clinical yield was not observed in association with higher neck imaging rates whether that yield was expressed as a percentage of total cases positive for clinically significant injury (p  =  0.29) or as a percentage of neck-imaged cases that were positive (p  =  0.77). We observed increases in the use of diagnostic images over time, reflecting a need to reinforce an existing clinical decision rule for cervical spine radiography. Temporal increases in the clinical yield for total cases may suggest a changing case mix or more judicious use of advanced types of diagnostic imaging.

  15. Diagnostic imaging of solitary tumors of the spine: what to do and say.

    PubMed

    Rodallec, Mathieu H; Feydy, Antoine; Larousserie, Frédérique; Anract, Philippe; Campagna, Raphaël; Babinet, Antoine; Zins, Marc; Drapé, Jean-Luc

    2008-01-01

    Metastatic disease, myeloma, and lymphoma are the most common malignant spinal tumors. Hemangioma is the most common benign tumor of the spine. Other primary osseous lesions of the spine are more unusual but may exhibit characteristic imaging features that can help the radiologist develop a differential diagnosis. Radiologic evaluation of a patient who presents with osseous vertebral lesions often includes radiography, computed tomography (CT), and magnetic resonance (MR) imaging. Because of the complex anatomy of the vertebrae, CT is more useful than conventional radiography for evaluating lesion location and analyzing bone destruction and condensation. The diagnosis of spinal tumors is based on patient age, topographic features of the tumor, and lesion pattern as seen at CT and MR imaging. A systematic approach is useful for recognizing tumors of the spine with characteristic features such as bone island, osteoid osteoma, osteochondroma, chondrosarcoma, vertebral angioma, and aneurysmal bone cyst. In the remaining cases, the differential diagnosis may include other primary spinal tumors, vertebral metastases and major nontumoral lesions simulating a vertebral tumor, Paget disease, spondylitis, echinococcal infection, and aseptic osteitis. In many cases, vertebral biopsy is warranted to guide treatment.

  16. Quantifying bone marrow edema in the rheumatoid cervical spine using magnetic resonance imaging.

    PubMed

    Suppiah, Ravi; Doyle, Anthony; Rai, Raylynne; Dalbeth, Nicola; Lobo, Maria; Braun, Jürgen; McQueen, Fiona M

    2010-08-01

    To determine the reliability and feasibility of a new magnetic resonance imaging (MRI) score to quantify bone marrow edema (BME), synovitis, and erosions in the cervical spine of patients with rheumatoid arthritis (RA); and to investigate the correlations among neck pain, clinical markers of RA disease activity, and MRI features of disease activity in the cervical spine. Thirty patients with RA (50% with neck pain) and a Disease Activity Score 28-joint count > 3.2 had an MRI scan of their cervical spine. STIR, VIBE, and T1-weighted postcontrast sequences were used to quantify BME. MRI scans were scored for total BME, synovitis, and erosions using a new scoring method developed by the authors and assessed for reliability and feasibility. Associations between neck pain and clinical markers of disease activity were investigated. BME was present in 14/30 patients; 9/14 (64%) had atlantoaxial BME, 10/14 (71%) had subaxial BME, and 5/14 (36%) had both. Interobserver reliability for total cervical BME score was moderate [intraclass correlation coefficient (ICC) = 0.51]. ICC improved to 0.67 if only the vertebral bodies and dens were considered. There was no correlation between neck pain or clinical measures of RA disease activity and the presence of any MRI features including BME, synovitis, or erosions. Current RA disease activity scores do not identify activity in the cervical spine. An MRI score that quantifies BME, synovitis, and erosions in the cervical spine may provide useful information regarding inflammation and damage. This could alert clinicians to the presence of significant pathology and influence management.

  17. Role of Anatomical Landmarks in Identifying Normal and Transitional Vertebra in Lumbar Spine Magnetic Resonance Imaging

    PubMed Central

    Indiran, Venkatraman; Hithaya, Fouzal; Alamelu, M.; Padmanaban, S.

    2017-01-01

    Study Design Retrospective study. Purpose Identification of transitional vertebra is important in spine imaging, especially in presurgical planning. Pasted images of the whole spine obtained using high-field magnetic resonance imaging (MRI) are helpful in counting vertebrae and identifying transitional vertebrae. Counting vertebrae and identifying transitional vertebrae is challenging in isolated studies of lumbar spine and in studies conducted in low-field MRI. An incorrect evaluation may lead to wrong-level treatment. Here, we identify the location of different anatomical structures that can help in counting and identifying vertebrae. Overview of Literature Many studies have assessed the vertebral segments using various anatomical structures such as costal facets (CF), aortic bifurcation (AB), inferior vena cava confluence (IC), right renal artery (RRA), celiac trunk (CT), superior mesenteric artery root (SR), iliolumbar ligament (ILL) psoas muscle (PM) origin, and conus medullaris. However, none have yielded any consistent results. Methods We studied the locations of the anatomical structures CF, AB, IC, RRA, CT, SR, ILL, and PM in patients who underwent whole spine MRI at our department. Results In our study, 81.4% patients had normal spinal segmentation, 14.7% had sacralization, and 3.8% had lumbarization. Vascular landmarks had variable origin. There were caudal and cranial shifts with respect to lumbarization and sacralization. In 93.8% of cases in the normal group, ILL emerged from either L5 alone or the adjacent disc. In the sacralization group, ILL was commonly seen in L5. In the lumbarization group, ILL emerged from L5 and the adjacent disc (66.6%). CFs were identified at D12 in 96.9% and 91.7% of patients in the normal and lumbarization groups, respectively. The PM origin was observed from D12 or D12–L1 in most patients in the normal and sacralization groups. Conclusions CF, PM, and ILL were good identification markers for D12 and L5, but none were

  18. Quantification of trunk and android lean mass using dual energy x-ray absorptiometry compared to magnetic resonance imaging after spinal cord injury.

    PubMed

    Rankin, Kathleen C; O'Brien, Laura C; Gorgey, Ashraf S

    2018-02-20

    To determine whether dual energy x-ray absorptiometry (DXA) compared to magnetic resonance imaging (MRI) may accurately quantify trunk lean mass (LM) after chronic spinal cord injury (SCI) and to investigate the relationships between trunk LM, visceral adiposity, trunk fat mass and basal metabolic rate (BMR). Cross-sectional design and correlational analysis. Research setting in a medical center. Twenty-two men with motor complete paraplegia (n = 14; T4-T11) and tetraplegia (n = 8; C5-C7) were recruited as part of a clinical trial. Not applicable. Trunk and android LM were measured using DXA. The volume of six trunk muscle groups were then measured using MRI to quantify trunk LM-MRI. Subcutaneous and visceral adipose tissue (VAT) cross-sectional areas were also measured using MRI. After overnight fast, BMR was evaluated using indirect calorimetry. Trunk LM-DXA (24 ± 3.3 kg) and android LM-DXA (3.6 ± 0.7 kg) overestimated (P < 0.0001) trunk LM-MRI (1.7 ± 0.5 kg). Trunk LM-MRI = 0.088* log (trunk LM-DXA)-0.415; r 2 =0.29, SEE= 0.44 kg, P = 0.007. Trunk LM-MRI = 1.53* android LM-DXA + 0.126; r 2 =0.26, SEE= 0.21 kg, P = 0.018. Percentage trunk LM-MRI was inversely related to VAT (r=-0.79, P < 0.0001) and trunk fat mass (r=-0.83, P < 0.001). Only trunk LM-DXA was related to BMR (r = 0.61, P = 0.002). Persons with tetraplegia have 13% smaller trunk muscle cross-sectional areas (P = 0.036) compared to those with paraplegia. Trunk LM-DXA and android LM-DXA overestimated trunk LM-MRI. Percentage trunk LM-MRI, but not LM-DXA, was inversely related to trunk central adiposity. The findings highlight the importance of exercising trunk LM to attenuate cardio-metabolic disorders after SCI.

  19. Modeling and Measurement of 3D Deformation of Scoliotic Spine Using 2D X-ray Images

    NASA Astrophysics Data System (ADS)

    Li, Hao; Leow, Wee Kheng; Huang, Chao-Hui; Howe, Tet Sen

    Scoliosis causes deformations such as twisting and lateral bending of the spine. To correct scoliotic deformation, the extents of 3D spinal deformation need to be measured. This paper studies the modeling and measurement of scoliotic spine based on 3D curve model. Through modeling the spine as a 3D Cosserat rod, the 3D structure of a scoliotic spine can be recovered by obtaining the minimum potential energy registration of the rod to the scoliotic spine in the x-ray image. Test results show that it is possible to obtain accurate 3D reconstruction using only the landmarks in a single view, provided that appropriate boundary conditions and elastic properties are included as constraints.

  20. Can CT imaging of the chest, abdomen, and pelvis identify all vertebral injuries of the thoracolumbar spine without dedicated reformatting?

    PubMed

    Imran, Jonathan B; Madni, Tarik D; Pruitt, Jeffrey H; Cornelius, Canon; Subramanian, Madhu; Clark, Audra T; Mokdad, Ali A; Rizk, Paul; Minei, Joseph P; Cripps, Michael W; Eastman, Alexander L

    2018-07-01

    The main objective of this study was to compare detection rates of clinically significant thoracolumbar spine (TLS) fracture between computed tomography (CT) imaging of the chest, abdomen, and spine (CT CAP) and CT for the thoracolumbar spine (CT TL). We retrospectively identified patients at our institution with a TLS fracture over a two-year period that had both CT CAP and reformatted CT TL imaging. The sensitivity of CT CAP to identify fracture was calculated for each fracture type. A total of 516 TLS fractures were identified in 125 patients using reformatted CT TL spine imaging. Overall, 69 of 512 fractures (13%) were missed on CT CAP that were identified on CT TL. Of those, there were no clinically significant missed fractures. CT CAP could potentially be used as a screening tool for clinically significant TLS injuries. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. ‘Abnormal’ cervical imaging?: Cervical pneumatocysts – A case report of a cervical spine pneumatocyst

    PubMed Central

    Renshaw, Hanna; Patel, Amit; Boctor, Daniel Sherif Zakaria Matta; Hakmi, Mohamed Atef

    2015-01-01

    To our knowledge there are only 15 reported cases of pneumatocysts in the cervical spine, but awareness of their existence should help the clinician when diagnosing abnormalities in radiological images. When faced with intravertebral gas, in addition to considering more sinister causes, one should consider the differentials including pneumatocysts. Despite our relative lack of understanding of these benign lesions the knowledge that they can change over time should prevent unnecessary testing or treating. We present a patient who fell down stairs and was found to have cervical intravertebral gas, on computed tomography imaging, with the typical appearance of a pneumatocyst. PMID:26719615

  2. 'Abnormal' cervical imaging?: Cervical pneumatocysts - A case report of a cervical spine pneumatocyst.

    PubMed

    Renshaw, Hanna; Patel, Amit; Boctor, Daniel Sherif Zakaria Matta; Hakmi, Mohamed Atef

    2015-10-01

    To our knowledge there are only 15 reported cases of pneumatocysts in the cervical spine, but awareness of their existence should help the clinician when diagnosing abnormalities in radiological images. When faced with intravertebral gas, in addition to considering more sinister causes, one should consider the differentials including pneumatocysts. Despite our relative lack of understanding of these benign lesions the knowledge that they can change over time should prevent unnecessary testing or treating. We present a patient who fell down stairs and was found to have cervical intravertebral gas, on computed tomography imaging, with the typical appearance of a pneumatocyst.

  3. Supersensitive Ras activation in dendrites and spines revealed by two-photon fluorescence lifetime imaging.

    PubMed

    Yasuda, Ryohei; Harvey, Christopher D; Zhong, Haining; Sobczyk, Aleksander; van Aelst, Linda; Svoboda, Karel

    2006-02-01

    To understand the biochemical signals regulated by neural activity, it is necessary to measure protein-protein interactions and enzymatic activity in neuronal microcompartments such as axons, dendrites and their spines. We combined two-photon excitation laser scanning with fluorescence lifetime imaging to measure fluorescence resonance energy transfer at high resolutions in brain slices. We also developed sensitive fluorescent protein-based sensors for the activation of the small GTPase protein Ras with slow (FRas) and fast (FRas-F) kinetics. Using FRas-F, we found in CA1 hippocampal neurons that trains of back-propagating action potentials rapidly and reversibly activated Ras in dendrites and spines. The relationship between firing rate and Ras activation was highly nonlinear (Hill coefficient approximately 5). This steep dependence was caused by a highly cooperative interaction between calcium ions (Ca(2+)) and Ras activators. The Ras pathway therefore functions as a supersensitive threshold detector for neural activity and Ca(2+) concentration.

  4. An edge-directed interpolation method for fetal spine MR images.

    PubMed

    Yu, Shaode; Zhang, Rui; Wu, Shibin; Hu, Jiani; Xie, Yaoqin

    2013-10-10

    Fetal spinal magnetic resonance imaging (MRI) is a prenatal routine for proper assessment of fetus development, especially when suspected spinal malformations occur while ultrasound fails to provide details. Limited by hardware, fetal spine MR images suffer from its low resolution.High-resolution MR images can directly enhance readability and improve diagnosis accuracy. Image interpolation for higher resolution is required in clinical situations, while many methods fail to preserve edge structures. Edge carries heavy structural messages of objects in visual scenes for doctors to detect suspicions, classify malformations and make correct diagnosis. Effective interpolation with well-preserved edge structures is still challenging. In this paper, we propose an edge-directed interpolation (EDI) method and apply it on a group of fetal spine MR images to evaluate its feasibility and performance. This method takes edge messages from Canny edge detector to guide further pixel modification. First, low-resolution (LR) images of fetal spine are interpolated into high-resolution (HR) images with targeted factor by bi-linear method. Then edge information from LR and HR images is put into a twofold strategy to sharpen or soften edge structures. Finally a HR image with well-preserved edge structures is generated. The HR images obtained from proposed method are validated and compared with that from other four EDI methods. Performances are evaluated from six metrics, and subjective analysis of visual quality is based on regions of interest (ROI). All these five EDI methods are able to generate HR images with enriched details. From quantitative analysis of six metrics, the proposed method outperforms the other four from signal-to-noise ratio (SNR), peak signal-to-noise ratio (PSNR), structure similarity index (SSIM), feature similarity index (FSIM) and mutual information (MI) with seconds-level time consumptions (TC). Visual analysis of ROI shows that the proposed method maintains

  5. Magnetic Resonance Imaging Interpretation in Patients With Symptomatic Lumbar Spine Disc Herniations

    PubMed Central

    Lurie, Jon D.; Doman, David M.; Spratt, Kevin F.; Tosteson, Anna N. A.; Weinstein, James N.

    2009-01-01

    Study Design Retrospective review of imaging data from a clinical trial. Objective To compare the interpretation of lumbar spine magnetic resonance imaging (MRIs) by clinical spine specialists and radiologists in patients with lumbar disc herniation. Summary of Background Data MRI is the imaging modality of choice for evaluation of the lumbar spine in patients with suspected lumbar disc herniation. Guidelines provide standardization of terms to more consistently describe disc herniation. The extent to which these guidelines are being followed in clinical practice is unknown. Methods We abstracted data from radiology reports from patients with lumbar intervertebral disc herniation enrolled in the Spine Patient Outcomes Research Trial. We evaluated the frequency with which morphology (e.g., protrusions, extrusions, or sequestrations) was reported as per guidelines and when present we compared the morphology ratings to those of clinicians who completed a structured data form as part of the trial. We assessed agreement using percent agreement and the κ statistic. Results There were 396 patients with sufficient data to analyze. Excellent agreement was observed between clinician and radiologist on the presence and level of herniation (93.4%), with 3.3% showing disagreement regarding level, of which a third could be explained by the presence of a transitional vertebra. In 3.3% of the cases in which the clinician reported a herniation (protrusion, extrusion, or sequestration), the radiologist reported no herniation on the MRI. The radiology reports did not clearly describe morphology in 42.2% of cases. In the 214 cases with clear morphologic descriptions, agreement was fair (κ = 0.24) and the disagreement was asymmetric (Bowker’s test of symmetry P < 0.0001) with clinicians more often rating more abnormal morphologic categories. Agreement on axial location of the herniation was excellent (κ = 0.81). There was disagreement between left or right side in only 3.3% of

  6. Occupational and patient exposure as well as image quality for full spine examinations with the EOS imaging system

    SciTech Connect

    Damet, J., E-mail: jerome.damet@chuv.ch; Fournier, P.; Monnin, P.

    Purpose: EOS (EOS imaging S.A, Paris, France) is an x-ray imaging system that uses slot-scanning technology in order to optimize the trade-off between image quality and dose. The goal of this study was to characterize the EOS system in terms of occupational exposure, organ doses to patients as well as image quality for full spine examinations. Methods: Occupational exposure was determined by measuring the ambient dose equivalents in the radiological room during a standard full spine examination. The patient dosimetry was performed using anthropomorphic phantoms representing an adolescent and a five-year-old child. The organ doses were measured with thermoluminescent detectorsmore » and then used to calculate effective doses. Patient exposure with EOS was then compared to dose levels reported for conventional radiological systems. Image quality was assessed in terms of spatial resolution and different noise contributions to evaluate the detector's performances of the system. The spatial-frequency signal transfer efficiency of the imaging system was quantified by the detective quantum efficiency (DQE). Results: The use of a protective apron when the medical staff or parents have to stand near to the cubicle in the radiological room is recommended. The estimated effective dose to patients undergoing a full spine examination with the EOS system was 290μSv for an adult and 200 μSv for a child. MTF and NPS are nonisotropic, with higher values in the scanning direction; they are in addition energy-dependent, but scanning speed independent. The system was shown to be quantum-limited, with a maximum DQE of 13%. The relevance of the DQE for slot-scanning system has been addressed. Conclusions: As a summary, the estimated effective dose was 290μSv for an adult; the image quality remains comparable to conventional systems.« less

  7. Preflight, In-Flight, and Postflight Imaging of the Cervical and Lumbar Spine in Astronauts.

    PubMed

    Harrison, Michael F; Garcia, Kathleen M; Sargsyan, Ashot E; Ebert, Douglas; Riascos-Castaneda, Roy F; Dulchavsky, Scott A

    2018-01-01

    Back pain is a common complaint during spaceflight that is commonly attributed to intervertebral disc swelling in microgravity. Ultrasound (US) represents the only imaging modality on the International Space Station (ISS) to assess its etiology. The present study investigated: 1) The agreement and correlation of spinal US assessments as compared to results of pre- and postflight MRI studies; and 2) the trend in intervertebral disc characteristics over the course of spaceflight to ISS. Seven ISS astronauts underwent pre- and postflight US examinations that included anterior disc height and anterior intervertebral angles with comparison to pre- and postflight MRI results. In-flight US images were analyzed for changes in disc height and angle. Statistical analysis included repeated measures ANOVA with Bonferroni post hoc analysis, Bland-Altman plots, and Pearson correlation. Bland-Altman plots revealed significant disagreement between disc heights and angles for MRI and US measurements while significant Pearson correlations were found in MRI and US measurements for lumbar disc height (r2 = 0.83) and angle (r2 = 0.89), but not for cervical disc height (r2 = 0.26) or angle (r2 = 0.02). Changes in anterior intervertebral disc angle-initially increases followed by decreases-were observed in the lumbar and cervical spine over the course of the long-duration mission. The cervical spine demonstrated a loss of total disc height during in-flight assessments (∼0.5 cm). Significant disagreement but significant correlation was noted between US and MRI measurements of disc height and angle. Consistency in imaging modality is important for trending measurements and more research related to US technique is required.Harrison MF, Garcia KM, Sargsyan AE, Ebert D, Riascos-Castaneda RF, Dulchavsky SA. Preflight, in-flight, and postflight imaging of the cervical and lumbar spine in astronauts. Aerosp Med Hum Perform. 2018; 89(1):32-40.

  8. Navigation and Image Injection for Control of Bone Removal and Osteotomy Planes in Spine Surgery.

    PubMed

    Kosterhon, Michael; Gutenberg, Angelika; Kantelhardt, Sven Rainer; Archavlis, Elefterios; Giese, Alf

    2017-04-01

    In contrast to cranial interventions, neuronavigation in spinal surgery is used in few applications, not tapping into its full technological potential. We have developed a method to preoperatively create virtual resection planes and volumes for spinal osteotomies and export 3-D operation plans to a navigation system controlling intraoperative visualization using a surgical microscope's head-up display. The method was developed using a Sawbone ® model of the lumbar spine, demonstrating feasibility with high precision. Computer tomographic and magnetic resonance image data were imported into Amira ® , a 3-D visualization software. Resection planes were positioned, and resection volumes representing intraoperative bone removal were defined. Fused to the original Digital Imaging and Communications in Medicine data, the osteotomy planes were exported to the cranial version of a Brainlab ® navigation system. A navigated surgical microscope with video connection to the navigation system allowed intraoperative image injection to visualize the preplanned resection planes. The workflow was applied to a patient presenting with a congenital hemivertebra of the thoracolumbar spine. Dorsal instrumentation with pedicle screws and rods was followed by resection of the deformed vertebra guided by the in-view image injection of the preplanned resection planes into the optical path of a surgical microscope. Postoperatively, the patient showed no neurological deficits, and the spine was found to be restored in near physiological posture. The intraoperative visualization of resection planes in a microscope's head-up display was found to assist the surgeon during the resection of a complex-shaped bone wedge and may help to further increase accuracy and patient safety. Copyright © 2017 by the Congress of Neurological Surgeons

  9. [Research on the range of motion measurement system for spine based on LabVIEW image processing technology].

    PubMed

    Li, Xiaofang; Deng, Linhong; Lu, Hu; He, Bin

    2014-08-01

    A measurement system based on the image processing technology and developed by LabVIEW was designed to quickly obtain the range of motion (ROM) of spine. NI-Vision module was used to pre-process the original images and calculate the angles of marked needles in order to get ROM data. Six human cadaveric thoracic spine segments T7-T10 were selected to carry out 6 kinds of loads, including left/right lateral bending, flexion, extension, cis/counterclockwise torsion. The system was used to measure the ROM of segment T8-T9 under the loads from 1 Nm to 5 Nm. The experimental results showed that the system is able to measure the ROM of the spine accurately and quickly, which provides a simple and reliable tool for spine biomechanics investigators.

  10. Optimization of spine surgery planning with 3D image templating tools

    NASA Astrophysics Data System (ADS)

    Augustine, Kurt E.; Huddleston, Paul M.; Holmes, David R., III; Shridharani, Shyam M.; Robb, Richard A.

    2008-03-01

    The current standard of care for patients with spinal disorders involves a thorough clinical history, physical exam, and imaging studies. Simple radiographs provide a valuable assessment but prove inadequate for surgery planning because of the complex 3-dimensional anatomy of the spinal column and the close proximity of the neural elements, large blood vessels, and viscera. Currently, clinicians still use primitive techniques such as paper cutouts, pencils, and markers in an attempt to analyze and plan surgical procedures. 3D imaging studies are routinely ordered prior to spine surgeries but are currently limited to generating simple, linear and angular measurements from 2D views orthogonal to the central axis of the patient. Complex spinal corrections require more accurate and precise calculation of 3D parameters such as oblique lengths, angles, levers, and pivot points within individual vertebra. We have developed a clinician friendly spine surgery planning tool which incorporates rapid oblique reformatting of each individual vertebra, followed by interactive templating for 3D placement of implants. The template placement is guided by the simultaneous representation of multiple 2D section views from reformatted orthogonal views and a 3D rendering of individual or multiple vertebrae enabling superimposition of virtual implants. These tools run efficiently on desktop PCs typically found in clinician offices or workrooms. A preliminary study conducted with Mayo Clinic spine surgeons using several actual cases suggests significantly improved accuracy of pre-operative measurements and implant localization, which is expected to increase spinal procedure efficiency and safety, and reduce time and cost of the operation.

  11. The internal architecture of dendritic spines revealed by super-resolution imaging: What did we learn so far?

    SciTech Connect

    MacGillavry, Harold D., E-mail: h.d.macgillavry@uu.nl; Hoogenraad, Casper C., E-mail: c.hoogenraad@uu.nl

    2015-07-15

    The molecular architecture of dendritic spines defines the efficiency of signal transmission across excitatory synapses. It is therefore critical to understand the mechanisms that control the dynamic localization of the molecular constituents within spines. However, because of the small scale at which most processes within spines take place, conventional light microscopy techniques are not adequate to provide the necessary level of resolution. Recently, super-resolution imaging techniques have overcome the classical barrier imposed by the diffraction of light, and can now resolve the localization and dynamic behavior of proteins within small compartments with nanometer precision, revolutionizing the study of dendritic spinemore » architecture. Here, we highlight exciting new findings from recent super-resolution studies on neuronal spines, and discuss how these studies revealed important new insights into how protein complexes are assembled and how their dynamic behavior shapes the efficiency of synaptic transmission.« less

  12. Kinetic magnetic resonance imaging analysis of abnormal segmental motion of the functional spine unit.

    PubMed

    Kong, Min Ho; Hymanson, Henry J; Song, Kwan Young; Chin, Dong Kyu; Cho, Yong Eun; Yoon, Do Heum; Wang, Jeffrey C

    2009-04-01

    The authors conducted a retrospective observational study using kinetic MR imaging to investigate the relationship between instability, abnormal sagittal segmental motion, and radiographic variables consisting of intervertebral disc degeneration, facet joint osteoarthritis (FJO), degeneration of the interspinous ligaments, ligamentum flavum hypertrophy (LFH), and the status of the paraspinal muscles. Abnormal segmental motion, defined as > 10 degrees angulation and > 3 mm of translation in the sagittal plane, was investigated in 1575 functional spine units (315 patients) in flexion, neutral, and extension postures using kinetic MR imaging. Each segment was assessed based on the extent of disc degeneration (Grades I-V), FJO (Grades 1-4), interspinous ligament degeneration (Grades 1-4), presence of LFH, and paraspinal muscle fatty infiltration observed on kinetic MR imaging. These factors are often noted in patients with degenerative disease, and there are grading systems to describe these changes. For the first time, the authors attempted to address the relationship between these radiographic observations and the effects on the motion and instability of the functional spine unit. The prevalence of abnormal translational motion was significantly higher in patients with Grade IV degenerative discs and Grade 3 arthritic facet joints (p < 0.05). In patients with advanced disc degeneration and FJO, there was a lesser amount of motion in both segmental translation and angulation when compared with lower grades of degeneration, and this difference was statistically significant for angular motion (p < 0.05). Patients with advanced degenerative Grade 4 facet joint arthritis had a significantly lower percentage of abnormal angular motion compared to patients with normal facet joints (p < 0.001). The presence of LFH was strongly associated with abnormal translational and angular motion. Grade 4 interspinous ligament degeneration and the presence of paraspinal muscle fatty

  13. Imaging Features of the Brain, Cerebral Vessels and Spine in Pediatric Tuberculous Meningitis with Associated Hydrocephalus

    PubMed Central

    Rohlwink, Ursula K; Kilborn, Tracy; Wieselthaler, Nicky; Banderker, Ebrahim; Zwane, Eugene; Figaji, Anthony A.

    2016-01-01

    Background Pediatric tuberculous meningitis leads to high rates of mortality and morbidity. Prompt diagnosis and initiation of treatment are challenging; imaging findings play a key role in establishing the presumptive diagnosis. General brain imaging findings are well reported; however, specific data on cerebral vascular and spinal involvement in children are sparse. Methods This prospective cohort study examined admission and follow up computed tomography brain scans and magnetic resonance imaging scans of the brain, cerebral vessels (magnetic resonance angiogram) and spine at 3 weeks in children treated for tuberculous meningitis with hydrocephalus (inclusion criteria). Exclusion criteria were no hydrocephalus on admission, treatment of hydrocephalus or commencement of anti-TB treatment before study enrolment. Imaging findings were examined in association with outcome at 6 months. Results Forty-four patients (median age 3.3 [0.3-13.1] years) with definite (54%) or probable tuberculous meningitis were enrolled. Good clinical outcome was reported in 72%; the mortality rate was 16%. Infarcts were reported in 66% of patients and were predictive of poor outcome. Magnetic resonance angiogram abnormalities were reported in 55% of patients. Delayed tuberculomas developed in 11% of patients (after starting treatment). Spinal pathology was more common than expected, occurring in 76% of patients. Exudate in the spinal canal increased the difficulty of lumbar puncture and correlated with high cerebrospinal fluid protein content. Conclusion Tuberculous meningitis involves extensive pathology in the central nervous system. Severe infarction was predictive of poor outcome although this was not the case for angiographic abnormalities. Spinal disease occurs commonly and has important implications for diagnosis and treatment. Comprehensive imaging of the brain, spine and cerebral vessels adds insight into disease pathophysiology. PMID:27213261

  14. Determination of the intervertebral disc space from CT images of the lumbar spine

    NASA Astrophysics Data System (ADS)

    Korez, Robert; Å tern, Darko; Likar, Boštjan; Pernuš, Franjo; Vrtovec, Tomaž

    2014-03-01

    Degenerative changes of the intervertebral disc are among the most common causes of low back pain, where for individuals with significant symptoms surgery may be needed. One of the interventions is the total disc replacement surgery, where the degenerated disc is replaced by an artificial implant. For designing implants with good bone contact and continuous force distribution, the morphology of the intervertebral disc space and vertebral body endplates is of considerable importance. In this study we propose a method for the determination of the intervertebral disc space from three-dimensional (3D) computed tomography (CT) images of the lumbar spine. The first step of the proposed method is the construction of a model of vertebral bodies in the lumbar spine. For this purpose, a chain of five elliptical cylinders is initialized in the 3D image and then deformed to resemble vertebral bodies by introducing 25 shape parameters. The parameters are obtained by aligning the chain to the vertebral bodies in the CT image according to image intensity and appearance information. The determination of the intervertebral disc space is finally achieved by finding the planes that fit the endplates of the obtained parametric 3D models, and placing points in the space between the planes of adjacent vertebrae that enable surface reconstruction of the intervertebral disc space. The morphometric analysis of images from 20 subjects yielded 11:3 +/- 2:6, 12:1 +/- 2:4, 12:8 +/- 2:0 and 12:9 +/- 2:7 cm3 in terms of L1-L2, L2-L3, L3-L4 and L4-L5 intervertebral disc space volume, respectively.

  15. Imaging Features of the Brain, Cerebral Vessels and Spine in Pediatric Tuberculous Meningitis With Associated Hydrocephalus.

    PubMed

    Rohlwink, Ursula K; Kilborn, Tracy; Wieselthaler, Nicky; Banderker, Ebrahim; Zwane, Eugene; Figaji, Anthony A

    2016-10-01

    Pediatric tuberculous meningitis (TBM) leads to high rates of mortality and morbidity. Prompt diagnosis and initiation of treatment are challenging; imaging findings play a key role in establishing the presumptive diagnosis. General brain imaging findings are well reported; however, specific data on cerebral vascular and spinal involvement in children are sparse. This prospective cohort study examined admission and followed up computed tomography brain scans and magnetic resonance imaging scans of the brain, cerebral vessels (magnetic resonance angiogram) and spine at 3 weeks in children treated for TBM with hydrocephalus (HCP; inclusion criteria). Exclusion criteria were no HCP on admission, treatment of HCP or commencement of antituberculosis treatment before study enrollment. Imaging findings were examined in association with outcome at 6 months. Forty-four patients (median age 3.3 [0.3-13.1] years) with definite (54%) or probable TBM were enrolled. Good clinical outcome was reported in 72%; the mortality rate was 16%. Infarcts were reported in 66% of patients and were predictive of poor outcome. Magnetic resonance angiogram abnormalities were reported in 55% of patients. Delayed tuberculomas developed in 11% of patients (after starting treatment). Spinal pathology was more common than expected, occurring in 76% of patients. Exudate in the spinal canal increased the difficulty of lumbar puncture and correlated with high cerebrospinal fluid protein content. TBM involves extensive pathology in the central nervous system. Severe infarction was predictive of poor outcome although this was not the case for angiographic abnormalities. Spinal disease occurs commonly and has important implications for diagnosis and treatment. Comprehensive imaging of the brain, spine and cerebral vessels adds insight into disease pathophysiology.

  16. MIND Demons: Symmetric Diffeomorphic Deformable Registration of MR and CT for Image-Guided Spine Surgery.

    PubMed

    Reaungamornrat, Sureerat; De Silva, Tharindu; Uneri, Ali; Vogt, Sebastian; Kleinszig, Gerhard; Khanna, Akhil J; Wolinsky, Jean-Paul; Prince, Jerry L; Siewerdsen, Jeffrey H

    2016-11-01

    Intraoperative localization of target anatomy and critical structures defined in preoperative MR/CT images can be achieved through the use of multimodality deformable registration. We propose a symmetric diffeomorphic deformable registration algorithm incorporating a modality-independent neighborhood descriptor (MIND) and a robust Huber metric for MR-to-CT registration. The method, called MIND Demons, finds a deformation field between two images by optimizing an energy functional that incorporates both the forward and inverse deformations, smoothness on the integrated velocity fields, a modality-insensitive similarity function suitable to multimodality images, and smoothness on the diffeomorphisms themselves. Direct optimization without relying on the exponential map and stationary velocity field approximation used in conventional diffeomorphic Demons is carried out using a Gauss-Newton method for fast convergence. Registration performance and sensitivity to registration parameters were analyzed in simulation, phantom experiments, and clinical studies emulating application in image-guided spine surgery, and results were compared to mutual information (MI) free-form deformation (FFD), local MI (LMI) FFD, normalized MI (NMI) Demons, and MIND with a diffusion-based registration method (MIND-elastic). The method yielded sub-voxel invertibility (0.008 mm) and nonzero-positive Jacobian determinants. It also showed improved registration accuracy in comparison to the reference methods, with mean target registration error (TRE) of 1.7 mm compared to 11.3, 3.1, 5.6, and 2.4 mm for MI FFD, LMI FFD, NMI Demons, and MIND-elastic methods, respectively. Validation in clinical studies demonstrated realistic deformations with sub-voxel TRE in cases of cervical, thoracic, and lumbar spine.

  17. MIND Demons: Symmetric Diffeomorphic Deformable Registration of MR and CT for Image-Guided Spine Surgery

    PubMed Central

    Reaungamornrat, Sureerat; De Silva, Tharindu; Uneri, Ali; Vogt, Sebastian; Kleinszig, Gerhard; Khanna, Akhil J; Wolinsky, Jean-Paul; Prince, Jerry L.

    2016-01-01

    Intraoperative localization of target anatomy and critical structures defined in preoperative MR/CT images can be achieved through the use of multimodality deformable registration. We propose a symmetric diffeomorphic deformable registration algorithm incorporating a modality-independent neighborhood descriptor (MIND) and a robust Huber metric for MR-to-CT registration. The method, called MIND Demons, finds a deformation field between two images by optimizing an energy functional that incorporates both the forward and inverse deformations, smoothness on the integrated velocity fields, a modality-insensitive similarity function suitable to multimodality images, and smoothness on the diffeomorphisms themselves. Direct optimization without relying on the exponential map and stationary velocity field approximation used in conventional diffeomorphic Demons is carried out using a Gauss-Newton method for fast convergence. Registration performance and sensitivity to registration parameters were analyzed in simulation, phantom experiments, and clinical studies emulating application in image-guided spine surgery, and results were compared to mutual information (MI) free-form deformation (FFD), local MI (LMI) FFD, normalized MI (NMI) Demons, and MIND with a diffusion-based registration method (MIND-elastic). The method yielded sub-voxel invertibility (0.008 mm) and nonzero-positive Jacobian determinants. It also showed improved registration accuracy in comparison to the reference methods, with mean target registration error (TRE) of 1.7 mm compared to 11.3, 3.1, 5.6, and 2.4 mm for MI FFD, LMI FFD, NMI Demons, and MIND-elastic methods, respectively. Validation in clinical studies demonstrated realistic deformations with sub-voxel TRE in cases of cervical, thoracic, and lumbar spine. PMID:27295656

  18. Semiautomatic computer-aided classification of degenerative lumbar spine disease in magnetic resonance imaging.

    PubMed

    Ruiz-España, Silvia; Arana, Estanislao; Moratal, David

    2015-07-01

    Computer-aided diagnosis (CAD) methods for detecting and classifying lumbar spine disease in Magnetic Resonance imaging (MRI) can assist radiologists to perform their decision-making tasks. In this paper, a CAD software has been developed able to classify and quantify spine disease (disc degeneration, herniation and spinal stenosis) in two-dimensional MRI. A set of 52 lumbar discs from 14 patients was used for training and 243 lumbar discs from 53 patients for testing in conventional two-dimensional MRI of the lumbar spine. To classify disc degeneration according to the gold standard, Pfirrmann classification, a method based on the measurement of disc signal intensity and structure was developed. A gradient Vector Flow algorithm was used to extract disc shape features and for detecting contour abnormalities. Also, a signal intensity method was used for segmenting and detecting spinal stenosis. Novel algorithms have also been developed to quantify the severity of these pathologies. Variability was evaluated by kappa (k) and intra-class correlation (ICC) statistics. Segmentation inaccuracy was below 1%. Almost perfect agreement, as measured by the k and ICC statistics, was obtained for all the analyzed pathologies: disc degeneration (k=0.81 with 95% CI=[0.75..0.88]) with a sensitivity of 95.8% and a specificity of 92.6%, disc herniation (k=0.94 with 95% CI=[0.87..1]) with a sensitivity of 60% and a specificity of 87.1%, categorical stenosis (k=0.94 with 95% CI=[0.90..0.98]) and quantitative stenosis (ICC=0.98 with 95% CI=[0.97..0.98]) with a sensitivity of 70% and a specificity of 81.7%. The proposed methods are reproducible and should be considered as a possible alternative when compared to reference standards. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Approach to interpret images produced by new generations of multidetector CT scanners in post-operative spine.

    PubMed

    Zeitoun, Rania; Hussein, Manar

    2017-11-01

    To reach a practical approach to interpret MDCT findings in post-operative spine cases and to change the false belief of CT failure in the setting of instruments secondary to related artefacts. We performed observational retrospective analysis of premier, early and late MDCT scans in 68 post-operative spine patients, with emphasis on instruments related complications and osseous fusion status. We used a grading system for assessment of osseous fusion in 35 patients and we further analysed the findings in failure of fusion, grade (D). We observed a variety of instruments related complications (mostly screws medially penetrating the pedicle) and osseous fusion status in late scans. We graded 11 interbody and 14 posterolateral levels as osseous fusion failure, showing additional instruments related complications, end plates erosive changes, adjacent segments spondylosis and malalignment. Modern MDCT scanners provide high quality images and are strongly recommended in assessment of the instruments and status of osseous fusion. In post-operative imaging of the spine, it is essential to be aware for what you are looking for, in relevance to the date of surgery. Advances in knowledge: Modern MDCT scanners allow assessment of instruments position and integrity and osseous fusion status in post-operative spine. We propose a helpful algorithm to simplify interpreting post-operative spine imaging.

  20. Evaluation of a dedicated MDCT protocol using iterative image reconstruction after cervical spine trauma.

    PubMed

    Geyer, L L; Körner, M; Hempel, R; Deak, Z; Mueck, F G; Linsenmaier, U; Reiser, M F; Wirth, S

    2013-07-01

    To evaluate radiation exposure for 64-row computed tomography (CT) of the cervical spine comparing two optimized protocols using filtered back projection (FBP) and adaptive statistical iterative reconstruction (ASIR), respectively. Sixty-seven studies using FBP (scanner 1) were retrospectively compared with 80 studies using ASIR (scanner 2). The key scanning parameters were identical (120 kV dose modulation, 64 × 0.625 mm collimation, pitch 0.531:1). In protocol 2, the noise index (NI) was increased from 5 to 25, and ASIR and the high-definition (HD) mode were used. The scan length, CT dose index (CTDI), and dose-length product (DLP) were recorded. The image quality was analysed subjectively by using a three-point scale (0; 1; 2), and objectively by using a region of interest (ROI) analysis. Mann-Whitney U and Wilcoxon's test were used. In the FBP group, the mean CTDI was 21.43 mGy, mean scan length 186.3 mm, and mean DLP 441.15 mGy cm. In the ASIR group, the mean CTDI was 9.57 mGy, mean scan length 195.21 mm, and mean DLP 204.23 mGy cm. The differences were significant for CTDI and DLP (p < 0.001) and scan length (p = 0.01). There was no significant difference in the subjective image quality (p > 0.05). The estimated mean effective dose decreased from 2.38 mSv (FBP) to 1.10 mSv (ASIR). The radiation dose of 64-row MDCT can be reduced to a level comparable to plain radiography without loss of subjective image quality by implementation of ASIR in a dedicated cervical spine trauma protocol. These results might contribute to an improved relative risk-to-benefit ratio and support the justification of CT as a first-line imaging tool to evaluate cervical spine trauma. Copyright © 2013 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  1. Correlation of diffusion tensor imaging parameters with neural status in Pott's spine.

    PubMed

    Jain, Nikhil; Saini, Namita Singh; Kumar, Sudhir; Rajagopalan, Mukunth; Chakraborti, Kanti Lal; Jain, Anil Kumar

    2016-04-29

    Diffusion tensor imaging (DTI) has been used in cervical trauma and spondylotic myelopathy, and it has been found to correlate with neural deficit and prognosticate neural recovery. Such a correlation has not been studied in Pott's spine with paraplegia. Hence, this prospective study has been used to find correlation of DTI parameters with neural deficit in these patients. Thirty-four patients of spinal TB were enrolled and DTI was performed before the start of treatment and after six months. Fractional anisotropy (FA), Mean diffusivity (MD), and Tractography were studied. Neurological deficit was graded by the Jain and Sinha scoring. Changes in FA and MD at and below the site of lesion (SOL) were compared to above the SOL (control) using the unpaired t-test. Pre-treatment and post-treatment values were also compared using the paired t-test. Correlation of DTI parameters with neurological score was done by Pearson's correlation. Subjective assessment of Tractography images was done. Mean average FA was not significantly decreased at the SOL in patients with paraplegia as compared to control. After six months of treatment, a significant decrease (p = 0.02) in mean average FA at the SOL compared to pre-treatment was seen. Moderate positive correlation (r = 0.49) between mean average FA and neural score after six months of treatment was found. Tractography images were not consistent with severity of paraplegia. Unlike spondylotic myelopathy and trauma, epidural collection and its organized inflammatory tissue in Pott's spine precludes accurate assessment of diffusion characteristics of the compressed cord.

  2. Deformable image registration with local rigidity constraints for cone-beam CT-guided spine surgery

    NASA Astrophysics Data System (ADS)

    Reaungamornrat, S.; Wang, A. S.; Uneri, A.; Otake, Y.; Khanna, A. J.; Siewerdsen, J. H.

    2014-07-01

    Image-guided spine surgery (IGSS) is associated with reduced co-morbidity and improved surgical outcome. However, precise localization of target anatomy and adjacent nerves and vessels relative to planning information (e.g., device trajectories) can be challenged by anatomical deformation. Rigid registration alone fails to account for deformation associated with changes in spine curvature, and conventional deformable registration fails to account for rigidity of the vertebrae, causing unrealistic distortions in the registered image that can confound high-precision surgery. We developed and evaluated a deformable registration method capable of preserving rigidity of bones while resolving the deformation of surrounding soft tissue. The method aligns preoperative CT to intraoperative cone-beam CT (CBCT) using free-form deformation (FFD) with constraints on rigid body motion imposed according to a simple intensity threshold of bone intensities. The constraints enforced three properties of a rigid transformation—namely, constraints on affinity (AC), orthogonality (OC), and properness (PC). The method also incorporated an injectivity constraint (IC) to preserve topology. Physical experiments involving phantoms, an ovine spine, and a human cadaver as well as digital simulations were performed to evaluate the sensitivity to registration parameters, preservation of rigid body morphology, and overall registration accuracy of constrained FFD in comparison to conventional unconstrained FFD (uFFD) and Demons registration. FFD with orthogonality and injectivity constraints (denoted FFD+OC+IC) demonstrated improved performance compared to uFFD and Demons. Affinity and properness constraints offered little or no additional improvement. The FFD+OC+IC method preserved rigid body morphology at near-ideal values of zero dilatation ({ D} = 0.05, compared to 0.39 and 0.56 for uFFD and Demons, respectively) and shear ({ S} = 0.08, compared to 0.36 and 0.44 for uFFD and Demons

  3. Image guided percutaneous spine procedures using an optical see-through head mounted display: proof of concept and rationale.

    PubMed

    Deib, Gerard; Johnson, Alex; Unberath, Mathias; Yu, Kevin; Andress, Sebastian; Qian, Long; Osgood, Gregory; Navab, Nassir; Hui, Ferdinand; Gailloud, Philippe

    2018-05-30

    Optical see-through head mounted displays (OST-HMDs) offer a mixed reality (MixR) experience with unhindered procedural site visualization during procedures using high resolution radiographic imaging. This technical note describes our preliminary experience with percutaneous spine procedures utilizing OST-HMD as an alternative to traditional angiography suite monitors. MixR visualization was achieved using the Microsoft HoloLens system. Various spine procedures (vertebroplasty, kyphoplasty, and percutaneous discectomy) were performed on a lumbar spine phantom with commercially available devices. The HMD created a real time MixR environment by superimposing virtual posteroanterior and lateral views onto the interventionalist's field of view. The procedures were filmed from the operator's perspective. Videos were reviewed to assess whether key anatomic landmarks and materials were reliably visualized. Dosimetry and procedural times were recorded. The operator completed a questionnaire following each procedure, detailing benefits, limitations, and visualization mode preferences. Percutaneous vertebroplasty, kyphoplasty, and discectomy procedures were successfully performed using OST-HMD image guidance on a lumbar spine phantom. Dosimetry and procedural time compared favorably with typical procedural times. Conventional and MixR visualization modes were equally effective in providing image guidance, with key anatomic landmarks and materials reliably visualized. This preliminary study demonstrates the feasibility of utilizing OST-HMDs for image guidance in interventional spine procedures. This novel visualization approach may serve as a valuable adjunct tool during minimally invasive percutaneous spine treatment. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  4. Utility of Routine Outpatient Cervical Spine Imaging Following Anterior Cervical Corpectomy and Fusion.

    PubMed

    Desai, Atman; Pendharkar, Arjun V; Swienckowski, Jessica G; Ball, Perry A; Lollis, Scott; Simmons, Nathan E

    2015-11-23

    Construct failure is an uncommon but well-recognized complication following anterior cervical corpectomy and fusion (ACCF). In order to screen for these complications, many centers routinely image patients at outpatient visits following surgery. There remains, however, little data on the utility of such imaging. The electronic medical record of all patients undergoing anterior cervical corpectomy and fusion at Dartmouth-Hitchcock Medical Center between 2004 and 2009 were reviewed. All patients had routine cervical spine radiographs performed perioperatively. Follow-up visits up to two years postoperatively were analyzed.  Sixty-five patients (mean age 52.2) underwent surgery during the time period. Eighteen patients were female. Forty patients had surgery performed for spondylosis, 20 for trauma, three for tumor, and two for infection. Forty-three patients underwent one-level corpectomy, 20 underwent two-level corpectomy, and two underwent three-level corpectomy, using an allograft, autograft, or both. Sixty-two of the fusions were instrumented using a plate and 13 had posterior augmentation. Fifty-seven patients had follow-up with imaging at four to 12 weeks following surgery, 54 with plain radiographs, two with CT scans, and one with an MRI scan. Unexpected findings were noted in six cases. One of those patients, found to have asymptomatic recurrent kyphosis following a two-level corpectomy, had repeat surgery because of those findings. Only one further patient was found to have abnormal imaging up to two years, and this patient required no further intervention. Routine imaging after ACCF can demonstrate asymptomatic occurrences of clinically significant instrument failure. In 43 consecutive single-level ACCF however, routine imaging did not change management, even when an abnormality was discovered. This may suggest a limited role for routine imaging after ACCF in longer constructs involving multiple levels.

  5. Imaging characteristics of cervical spine extra-arachnoid fluid collections managed conservatively.

    PubMed

    Lawrence, David A; Trotta, Brian; Shen, Francis H; Druzgal, Jason T; Fox, Michael G

    2016-09-01

    Determine the MRI characteristics of large post-traumatic cervical spine extra-arachnoid collections managed conservatively in clinically stable patients and whether evidence of clinical or imaging deterioration materialized. Following IRB approval, we conducted a retrospective search for all patients (>16 years old) over a 17-months period who had an extra-arachnoid fluid collection reported on a post-traumatic cervical spine MRI. Patients were excluded if they had surgery for an unstable fracture (n = 21), emergent decompression (n = 1) or lacked a follow-up MRI within 15 days (n = 1). Two MSK radiologists recorded the size, morphology and MRI signal characteristics of the collections. Eight patients (5 male, 3 female) met the inclusion criteria (mean age 40 years; range 19-78 years). Seven of the eight patients had fluid collections that demonstrated thin, tapered margins, extended >7 vertebral bodies and involved >180 degrees of the spinal canal. The signal characteristics of these collections varied: hyper-T1/iso-T2 (n = 1), iso-T1/T2 (n = 3), hyper-T1/hypo-T2 (n = 3) and mixed-T1/T2 (n = 1). Six of seven collections were ventral. Follow-up MRI demonstrated resolution/significant decrease in size (n = 4 between 1 and 12 days) or no change/slight decrease in size (n = 3; between 2 and 11 days). None of the seven fluid collections enlarged, no patient had abnormal cord signal, and no patient's neurologic symptoms worsened. One of eight patients had a dorsal "mass-like" collection that was slightly smaller 9 days later. In stable patients with large, tapered post-traumatic cervical spine extra-arachnoid collections managed non-surgically, none developed (1) clinical worsening, (2) abnormal cord signal or (3) collection enlargement, regardless of the collection's signal characteristics.

  6. New generation intraoperative three-dimensional imaging (O-arm) in 100 spine surgeries: does it change the surgical procedure?

    PubMed

    Sembrano, Jonathan N; Santos, Edward Rainier G; Polly, David W

    2014-02-01

    The O-arm (Medtronic Sofamor Danek, Inc., Memphis, TN, USA), an intraoperative CT scan imaging system, may provide high-quality imaging information to the surgeon. To our knowledge, its impact on spine surgery has not been studied. We reviewed 100 consecutive spine surgical procedures which utilized the new generation mobile intraoperative CT imaging system (O-arm). The most common diagnoses were degenerative conditions (disk disease, spondylolisthesis, stenosis and acquired kyphosis), seen in 49 patients. The most common indication for imaging was spinal instrumentation in 81 patients (74 utilized pedicle screws). In 52 (70%) of these, the O-arm was used to assess screw position after placement; in 22 (30%), it was coupled with Stealth navigation (Medtronic Sofamor Danek, Inc.) to guide screw placement. Another indication was to assess adequacy of spinal decompression in 38 patients; in 19 (50%) of these, intrathecal contrast material was used to obtain an intraoperative CT myelogram. In 20 patients O-arm findings led to direct surgeon intervention in the form of screw removal/repositioning (n=13), further decompression (n=6), interbody spacer repositioning (n=1), and removal of kyphoplasty trocar (n=1). In 20% of spine surgeries, the procedure was changed based on O-arm imaging findings. We found the O-arm to be useful for assessment of instrumentation position, adequacy of spinal decompression, and confirmation of balloon containment and cement filling in kyphoplasty. When used with navigation for image-guided surgery, it obviated the need for registration. Published by Elsevier Ltd.

  7. Usefulness of Tc-99m MDP spine SPECT imaging in differentiating malignant from benign lesions in cancer patients

    SciTech Connect

    Ryu, J.S.; Moon, D.H.; Shin, M.J.

    1994-05-01

    Solitary or a few spinal abnormalities on planar bone scan pose a dilemma in cancer patients. The purpose of this study was to evaluate the usefulness of spine SPECT imaging in differential diagnosis of malignant and benign lesion. Subjects were 54 adult patients with solitary or a few equivocal vertebral lesions on planar bone scan. Spine SPECT imaging was obtained by a triple head SPECT system (TRIAD, Trionix). The final diagnoses were based on data from biopsy, other imaging studies, or minimum 1 year of follow up. Two blind observers reviewed the planar image first, then both planar and SPECTmore » images. The uptake patterns on SPECT images were analyzed, and the diagnostic performance was evaluated by the ROC analysis. Thirty three lesions of 22 patients were malignant, and 60 lesions of 32 patients were benign. Common characteristic patterns of malignant lesions were focal or segmental hot uptake in the body, hot uptake in the body and pedicle, and cold defect with surrounding hot uptake in the vertebra. Whereas marginal protruding hot uptakes in endplate, and hot uptakes in facet joints were benign. The ROC analysis showed that SPECT improved the diagnostic performance (the area under the ROC curve of two observers for planar image 0.903 and 0.791, for the combination of planar and SPECT : 0.950 and 0.976). In conclusion, the uptake pattern recognition in spine SPECT provides useful information for differential diagnosis of malignant and benign lesions in vertebra. Spine SPECT is a valuable complement in cancer patients with inconclusive findings on planar bone scan.« less

  8. Automatic exposure control calibration and optimisation for abdomen, pelvis and lumbar spine imaging with an Agfa computed radiography system.

    PubMed

    Moore, C S; Wood, T J; Avery, G; Balcam, S; Needler, L; Joshi, H; Saunderson, J R; Beavis, A W

    2016-11-07

    The use of three physical image quality metrics, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and mean effective noise equivalent quanta (eNEQ m ) have recently been examined by our group for their appropriateness in the calibration of an automatic exposure control (AEC) device for chest radiography with an Agfa computed radiography (CR) imaging system. This study uses the same methodology but investigates AEC calibration for abdomen, pelvis and spine CR imaging. AEC calibration curves were derived using a simple uniform phantom (equivalent to 20 cm water) to ensure each metric was held constant across the tube voltage range. Each curve was assessed for its clinical appropriateness by generating computer simulated abdomen, pelvis and spine images (created from real patient CT datasets) with appropriate detector air kermas for each tube voltage, and grading these against reference images which were reconstructed at detector air kermas correct for the constant detector dose indicator (DDI) curve currently programmed into the AEC device. All simulated images contained clinically realistic projected anatomy and were scored by experienced image evaluators. Constant DDI and CNR curves did not provide optimized performance but constant eNEQ m and SNR did, with the latter being the preferred calibration metric given that it is easier to measure in practice. This result was consistent with the previous investigation for chest imaging with AEC devices. Medical physicists may therefore use a simple and easily accessible uniform water equivalent phantom to measure the SNR image quality metric described here when calibrating AEC devices for abdomen, pelvis and spine imaging with Agfa CR systems, in the confidence that clinical image quality will be sufficient for the required clinical task. However, to ensure appropriate levels of detector air kerma the advice of expert image evaluators must be sought.

  9. Automatic exposure control calibration and optimisation for abdomen, pelvis and lumbar spine imaging with an Agfa computed radiography system

    NASA Astrophysics Data System (ADS)

    Moore, C. S.; Wood, T. J.; Avery, G.; Balcam, S.; Needler, L.; Joshi, H.; Saunderson, J. R.; Beavis, A. W.

    2016-11-01

    The use of three physical image quality metrics, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and mean effective noise equivalent quanta (eNEQm) have recently been examined by our group for their appropriateness in the calibration of an automatic exposure control (AEC) device for chest radiography with an Agfa computed radiography (CR) imaging system. This study uses the same methodology but investigates AEC calibration for abdomen, pelvis and spine CR imaging. AEC calibration curves were derived using a simple uniform phantom (equivalent to 20 cm water) to ensure each metric was held constant across the tube voltage range. Each curve was assessed for its clinical appropriateness by generating computer simulated abdomen, pelvis and spine images (created from real patient CT datasets) with appropriate detector air kermas for each tube voltage, and grading these against reference images which were reconstructed at detector air kermas correct for the constant detector dose indicator (DDI) curve currently programmed into the AEC device. All simulated images contained clinically realistic projected anatomy and were scored by experienced image evaluators. Constant DDI and CNR curves did not provide optimized performance but constant eNEQm and SNR did, with the latter being the preferred calibration metric given that it is easier to measure in practice. This result was consistent with the previous investigation for chest imaging with AEC devices. Medical physicists may therefore use a simple and easily accessible uniform water equivalent phantom to measure the SNR image quality metric described here when calibrating AEC devices for abdomen, pelvis and spine imaging with Agfa CR systems, in the confidence that clinical image quality will be sufficient for the required clinical task. However, to ensure appropriate levels of detector air kerma the advice of expert image evaluators must be sought.

  10. Oblique Sagittal Images Prevent Underestimation of the Neuroforaminal Stenosis Grade Caused by Disc Herniation in Cervical Spine MRI.

    PubMed

    Kintzelé, Laurent; Rehnitz, Christoph; Kauczor, Hans-Ulrich; Weber, Marc-André

    2018-06-06

     To identify whether standard sagittal MRI images result in underestimation of the neuroforaminal stenosis grade compared to oblique sagittal MRI images in patients with cervical spine disc herniation.  74 patients with a total of 104 cervical disc herniations compromising the corresponding nerve root were evaluated. Neuroforaminal stenosis grades were evaluated in standard and oblique sagittal images by one senior and one resident radiologist experienced in musculoskeletal imaging. Oblique images were angled 30° towards the standard sagittal plane. Neuroforaminal stenosis grades were classified from 0 (no stenosis) to 3 (high grade stenosis).  Average neuroforaminal stenosis grades of both readers were significantly lower in standard compared to oblique sagittal images (p < 0.001). For 47.1 % of the cases, one or both readers reported a stenosis grade, which was at least 1 grade lower in standard compared to oblique sagittal images. There was also a significant difference when looking at patients who had neurological symptoms (p = 0.002) or underwent cervical spine surgery subsequently (p = 0.004). Interreader reliability, as measured by kappa value, and accordance rates were better for oblique sagittal images (0.94 vs. 0.88 and 99 % vs. 93 %).  Standard sagittal images tend to underestimate neuroforaminal stenosis grades compared to oblique sagittal images and are less reliable in the evaluation of disc herniations within the cervical spine MRI. In order to assess the potential therapeutic consequence, oblique images should therefore be considered as a valuable adjunct to the standard MRI protocol for patients with a radiculopathy.   · Neuroforaminal stenosis grades are underestimated in standard compared to oblique sagittal images. · Interreader reliability is higher for oblique sagittal images. · Oblique sagittal images should be performed in patients with a cervical radiculopathy. · Kintzele L, Rehnitz C, Kauczor H et

  11. Achieving a neutral cervical spine position in suspected spinal cord injury in children: analysing the use of a thoracic elevation device for imaging the cervical spine in paediatric patients.

    PubMed

    Pandie, Zaahid; Shepherd, Mike; Lamont, Tony; Walsh, Mark; Phillips, Mark; Page, Colin

    2010-08-01

    Paediatric patients with suspected cervical spine injury (CSI) are routinely immobilised on a firm surface using a hard collar, which results in excessive flexion of the cervical spine due to the relatively large size of the occiput. The objective of this study was to determine whether the use of a thoracic elevation device (TED) results in a more neutral cervical spine position and reduces the occurrence of cervical spine hyperflexion. A prospective cohort study was conducted at two Emergency Departments (sites A and B) from January 2006 to May 2007. Children < or =10 years of age with suspected CSI requiring cervical imaging were included. Those at site A received a wedge-shaped TED and those at site B did not. x-Rays from both sites were analysed for flexion, extension or neutrality of the cervical spine as defined by the Cobb angle. A total of 76 patients were identified at site A and site B. There were four exclusions at each site for poor quality images. 51 patients in the site A group were found to be in neutral position (71%), compared to 29 patients in the site B group (43%) (p=0.001). One patient (1%) who had a TED was found to be hyperflexed (>10 degrees), whereas 12 (18%) patients at site B were hyperflexed (p=0.001). The use of a TED appears to produce a greater proportion of neutral cervical spine films in children < or =10 years of age presenting for suspected CSI.

  12. Inserting pedicle screws in the upper thoracic spine without the use of fluoroscopy or image guidance. Is it safe?

    PubMed

    Schizas, Constantin; Theumann, Nicolas; Kosmopoulos, Victor

    2007-05-01

    Several studies have looked at accuracy of thoracic pedicle screw placement using fluoroscopy, image guidance, and anatomical landmarks. To our knowledge the upper thoracic spine (T1-T6) has not been specifically studied in the context of screw insertion and placement accuracy without the use of either image guidance or fluoroscopy. Our objective was to study the accuracy of upper thoracic screw placement without the use of fluoroscopy or image guidance, and report on implant related complications. A single surgeon inserted 60 screws in 13 consecutive non-scoliotic spine patients. These were the first 60 screws placed in the high thoracic spine in our institution. The most common diagnosis in our patient population was trauma. All screws were inserted using a modified Roy-Camille technique. Post-operative axial computed tomography (CT) images were obtained for each patient and analyzed by an independent senior radiologist for placement accuracy. Implant related complications were prospectively noted. No pedicle screw misplacement was found in 61.5% of the patients. In the remaining 38.5% of patients some misplacements were noted. Fifty-three screws out of the total 60 implanted were placed correctly within all the pedicle margins. The overall pedicle screw placement accuracy was 88.3% using our modified Roy-Camille technique. Five medial and two lateral violations were noted in the seven misplaced screws. One of the seven misplaced screws was considered to be questionable in terms of pedicle perforation. No implant related complications were noted. We found that inserting pedicle screws in the upper thoracic spine based solely on anatomical landmarks was safe with an accuracy comparable to that of published studies using image-guided navigation at the thoracic level.

  13. Validation of cone-beam computed tomography and magnetic resonance imaging of the porcine spine: a comparative study with multidetector computed tomography and anatomical specimens.

    PubMed

    de Freitas, Ricardo Miguel Costa; Andrade, Celi Santos; Caldas, José Guilherme Mendes Pereira; Kanas, Alexandre Fligelman; Cabral, Richard Halti; Tsunemi, Miriam Harumi; Rodríguez, Hernán Joel Cervantes; Rabbani, Said Rahnamaye

    2015-05-01

    New spinal interventions or implants have been tested on ex vivo or in vivo porcine spines, as they are readily available and have been accepted as a comparable model to human cadaver spines. Imaging-guided interventional procedures of the spine are mostly based on fluoroscopy or, still, on multidetector computed tomography (MDCT). Cone-beam computed tomography (CBCT) and magnetic resonance imaging (MRI) are also available methods to guide interventional procedures. Although some MDCT data from porcine spines are available in the literature, validation of the measurements on CBCT and MRI is lacking. To describe and compare the anatomical measurements accomplished with MDCT, CBCT, and MRI of lumbar porcine spines to determine if CBCT and MRI are also useful methods for experimental studies. An experimental descriptive-comparative study. Sixteen anatomical measurements of an individual vertebra from six lumbar porcine spines (n=36 vertebrae) were compared with their MDCT, CBCT, and MRI equivalents. Comparisons were made for the absolute values of the parameters. Similarities were found in all imaging methods. Significant correlation (p<.05) was observed with all variables except those that included cartilaginous tissue from the end plates when the anatomical study was compared with the imaging methods. The CBCT and MRI provided imaging measurements of the lumbar porcine spines that were similar to the anatomical and MDCT data, and they can be useful for specific experimental research studies. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Imaging Performance of a Handheld Ultrasound System With Real-Time Computer-Aided Detection of Lumbar Spine Anatomy: A Feasibility Study.

    PubMed

    Tiouririne, Mohamed; Dixon, Adam J; Mauldin, F William; Scalzo, David; Krishnaraj, Arun

    2017-08-01

    The aim of this study was to evaluate the imaging performance of a handheld ultrasound system and the accuracy of an automated lumbar spine computer-aided detection (CAD) algorithm in the spines of human subjects. This study was approved by the institutional review board of the University of Virginia. The authors designed a handheld ultrasound system with enhanced bone image quality and fully automated CAD of lumbar spine anatomy. The imaging performance was evaluated by imaging the lumbar spines of 68 volunteers with body mass index between 18.5 and 48 kg/m. The accuracy, sensitivity, and specificity of the lumbar spine CAD algorithm were assessed by comparing the algorithm's results to ground-truth segmentations of neuraxial anatomy provided by radiologists. The lumbar spine CAD algorithm detected the epidural space with a sensitivity of 94.2% (95% confidence interval [CI], 85.1%-98.1%) and a specificity of 85.5% (95% CI, 81.7%-88.6%) and measured its depth with an error of approximately ±0.5 cm compared with measurements obtained manually from the 2-dimensional ultrasound images. The spine midline was detected with a sensitivity of 93.9% (95% CI, 85.8%-97.7%) and specificity of 91.3% (95% CI, 83.6%-96.9%), and its lateral position within the ultrasound image was measured with an error of approximately ±0.3 cm. The bone enhancement imaging mode produced images with 5.1- to 10-fold enhanced bone contrast when compared with a comparable handheld ultrasound imaging system. The results of this study demonstrate the feasibility of CAD for assisting with real-time interpretation of ultrasound images of the lumbar spine at the bedside.

  15. Investigating sub-spine actin dynamics in rat hippocampal neurons with super-resolution optical imaging.

    PubMed

    Tatavarty, Vedakumar; Kim, Eun-Ji; Rodionov, Vladimir; Yu, Ji

    2009-11-09

    Morphological changes in dendritic spines represent an important mechanism for synaptic plasticity which is postulated to underlie the vital cognitive phenomena of learning and memory. These morphological changes are driven by the dynamic actin cytoskeleton that is present in dendritic spines. The study of actin dynamics in these spines traditionally has been hindered by the small size of the spine. In this study, we utilize a photo-activation localization microscopy (PALM)-based single-molecule tracking technique to analyze F-actin movements with approximately 30-nm resolution in cultured hippocampal neurons. We were able to observe the kinematic (physical motion of actin filaments, i.e., retrograde flow) and kinetic (F-actin turn-over) dynamics of F-actin at the single-filament level in dendritic spines. We found that F-actin in dendritic spines exhibits highly heterogeneous kinematic dynamics at the individual filament level, with simultaneous actin flows in both retrograde and anterograde directions. At the ensemble level, movements of filaments integrate into a net retrograde flow of approximately 138 nm/min. These results suggest a weakly polarized F-actin network that consists of mostly short filaments in dendritic spines.

  16. Automated detection, 3D segmentation and analysis of high resolution spine MR images using statistical shape models

    NASA Astrophysics Data System (ADS)

    Neubert, A.; Fripp, J.; Engstrom, C.; Schwarz, R.; Lauer, L.; Salvado, O.; Crozier, S.

    2012-12-01

    Recent advances in high resolution magnetic resonance (MR) imaging of the spine provide a basis for the automated assessment of intervertebral disc (IVD) and vertebral body (VB) anatomy. High resolution three-dimensional (3D) morphological information contained in these images may be useful for early detection and monitoring of common spine disorders, such as disc degeneration. This work proposes an automated approach to extract the 3D segmentations of lumbar and thoracic IVDs and VBs from MR images using statistical shape analysis and registration of grey level intensity profiles. The algorithm was validated on a dataset of volumetric scans of the thoracolumbar spine of asymptomatic volunteers obtained on a 3T scanner using the relatively new 3D T2-weighted SPACE pulse sequence. Manual segmentations and expert radiological findings of early signs of disc degeneration were used in the validation. There was good agreement between manual and automated segmentation of the IVD and VB volumes with the mean Dice scores of 0.89 ± 0.04 and 0.91 ± 0.02 and mean absolute surface distances of 0.55 ± 0.18 mm and 0.67 ± 0.17 mm respectively. The method compares favourably to existing 3D MR segmentation techniques for VBs. This is the first time IVDs have been automatically segmented from 3D volumetric scans and shape parameters obtained were used in preliminary analyses to accurately classify (100% sensitivity, 98.3% specificity) disc abnormalities associated with early degenerative changes.

  17. Open MR imaging in spine surgery: experimental investigations and first clinical experiences.

    PubMed

    Verheyden, P; Katscher, S; Schulz, T; Schmidt, F; Josten, C

    1999-01-01

    The latest open MRI technology allows to perform open and closed surgical procedures under real-time imaging. Before performing spinal trauma surgery preclinical examinations had to be done to evaluate the artifacts caused by the implants. The MRT presented is a prototype developed by GE. Two vertically positioned magnetic coils are installed in an operation theater. By that means two surgeons are able to access the patient between the two coils. Numerous tests regarding the material of instruments and implants were necessary in advance. The specific size of the artifact depending on the pulse sequence and the positioning within the magnetic field had to be examined. The magnifying factors of the artifact in the spin echo sequence regarding titanium are between 1.7 and 3.2, depending on the direction of the magnetic vector. Regarding stainless steel they are between 8.4 and 8.5. In the gradient echo sequence the factors are between 7.5 and 7.7 for titanium and between 16.9 and 18.0 for stainless steel. The tip of an implant is imaged with an accuracy of 0 to 2 mm. Since September 1997 16 patients with unstable fractures of the thoracic and lumbar spine have been treated by dorsal instrumentation in the open MRI. Percutaneous insertion of the internal fixator has proven a successful minimally invasive procedure. The positioning of the screws in the pedicle is secure, the degree of indirect reduction of the posterior wall of the vertebral body can be imaged immediately. The diameter of the spinal canal can be determined in any plane. The open MRI has proven useful in orthopedic and trauma surgery. The size and configuration of the artifacts caused by instruments and implants is predictable. Therefore exact positioning of the implants is achieved more easily. Dorsal instrumentation of unstable thoracolumbar fractures with a percutaneous technique has turned out safe and less traumatic under MR-imaging. Real-time imaging of soft tissue and bone in any plane improves

  18. Impact of immersion oils and mounting media on the confocal imaging of dendritic spines

    PubMed Central

    Peterson, Brittni M.; Mermelstein, Paul G.; Meisel, Robert L.

    2015-01-01

    Background Structural plasticity, such as changes in dendritic spine morphology and density, reflect changes in synaptic connectivity and circuitry. Procedural variables used in different methods for labeling dendritic spines have been quantitatively evaluated for their impact on the ability to resolve individual spines in confocal microscopic analyses. In contrast, there have been discussions, though no quantitative analyses, of the potential effects of choosing specific mounting media and immersion oils on dendritic spine resolution. New Method Here we provide quantitative data measuring the impact of these variables on resolving dendritic spines in 3D confocal analyses. Medium spiny neurons from the rat striatum and nucleus accumbens are used as examples. Results Both choice of mounting media and immersion oil affected the visualization of dendritic spines, with choosing the appropriate immersion oil as being more imperative. These biologic data are supported by quantitative measures of the 3D diffraction pattern (i.e. point spread function) of a point source of light under the same mounting medium and immersion oil combinations. Comparison with Existing Method Although not a new method, this manuscript provides quantitative data demonstrating that different mounting media and immersion oils can impact the ability to resolve dendritic spines. These findings highlight the importance of reporting which mounting medium and immersion oil are used in preparations for confocal analyses, especially when comparing published results from different laboratories. Conclusion Collectively, these data suggest that choosing the appropriate immersion oil and mounting media is critical for obtaining the best resolution, and consequently more accurate measures of dendritic spine densities. PMID:25601477

  19. Impact of immersion oils and mounting media on the confocal imaging of dendritic spines.

    PubMed

    Peterson, Brittni M; Mermelstein, Paul G; Meisel, Robert L

    2015-03-15

    Structural plasticity, such as changes in dendritic spine morphology and density, reflect changes in synaptic connectivity and circuitry. Procedural variables used in different methods for labeling dendritic spines have been quantitatively evaluated for their impact on the ability to resolve individual spines in confocal microscopic analyses. In contrast, there have been discussions, though no quantitative analyses, of the potential effects of choosing specific mounting media and immersion oils on dendritic spine resolution. Here we provide quantitative data measuring the impact of these variables on resolving dendritic spines in 3D confocal analyses. Medium spiny neurons from the rat striatum and nucleus accumbens are used as examples. Both choice of mounting media and immersion oil affected the visualization of dendritic spines, with choosing the appropriate immersion oil as being more imperative. These biologic data are supported by quantitative measures of the 3D diffraction pattern (i.e. point spread function) of a point source of light under the same mounting medium and immersion oil combinations. Although not a new method, this manuscript provides quantitative data demonstrating that different mounting media and immersion oils can impact the ability to resolve dendritic spines. These findings highlight the importance of reporting which mounting medium and immersion oil are used in preparations for confocal analyses, especially when comparing published results from different laboratories. Collectively, these data suggest that choosing the appropriate immersion oil and mounting media is critical for obtaining the best resolution, and consequently more accurate measures of dendritic spine densities. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Magnetic resonance imaging of the calcaneus: preliminary assessment of trabecular bone-dependent regional variations in marrow relaxation time compared with dual X-ray absorptiometry

    NASA Technical Reports Server (NTRS)

    Guglielmi, G.; Selby, K.; Blunt, B. A.; Jergas, M.; Newitt, D. C.; Genant, H. K.; Majumdar, S.

    1996-01-01

    RATIONALE AND OBJECTIVES: Marrow transverse relaxation time (T2*) in magnetic resonance (MR) imaging may be related to the density and structure of the surrounding trabecular network. We investigated regional variations of T2* in the human calcaneus and compared the findings with bone mineral density (BMD), as measured by dual X-ray absorpiometry (DXA). Short- and long-term precisions were evaluated first to determine whether MR imaging would be useful for the clinical assessment of disease status and progression in osteoporosis. METHODS: Gradient-recalled echo MR images of the calcaneus were acquired at 1.5 T from six volunteers. Measurements of T2* were compared with BMD and (for one volunteer) conventional radiography. RESULTS: T2* values showed significant regional variation; they typically were shortest in the superior region of the calcaneus. There was a linear correlation between MR and DXA measurements (r = .66 for 1/T2* versus BMD). Differences in T2* attributable to variations in analysis region-of-interest placement were not significant for five of the six volunteers. Sagittal MR images had short- and long-term precision errors of 4.2% and 3.3%, respectively. For DXA, the precision was 1.3% (coefficient of variation). CONCLUSION: MR imaging may be useful for trabecular bone assessment in the calcaneus. However, given the large regional variations in bone density and structure, the choice of an ROI is likely to play a major role in the accuracy, precision, and overall clinical efficacy of T2* measurements.

  1. Automatic Masking for Robust 3D-2D Image Registration in Image-Guided Spine Surgery.

    PubMed

    Ketcha, M D; De Silva, T; Uneri, A; Kleinszig, G; Vogt, S; Wolinsky, J-P; Siewerdsen, J H

    During spinal neurosurgery, patient-specific information, planning, and annotation such as vertebral labels can be mapped from preoperative 3D CT to intraoperative 2D radiographs via image-based 3D-2D registration. Such registration has been shown to provide a potentially valuable means of decision support in target localization as well as quality assurance of the surgical product. However, robust registration can be challenged by mismatch in image content between the preoperative CT and intraoperative radiographs, arising, for example, from anatomical deformation or the presence of surgical tools within the radiograph. In this work, we develop and evaluate methods for automatically mitigating the effect of content mismatch by leveraging the surgical planning data to assign greater weight to anatomical regions known to be reliable for registration and vital to the surgical task while removing problematic regions that are highly deformable or often occluded by surgical tools. We investigated two approaches to assigning variable weight (i.e., "masking") to image content and/or the similarity metric: (1) masking the preoperative 3D CT ("volumetric masking"); and (2) masking within the 2D similarity metric calculation ("projection masking"). The accuracy of registration was evaluated in terms of projection distance error (PDE) in 61 cases selected from an IRB-approved clinical study. The best performing of the masking techniques was found to reduce the rate of gross failure (PDE > 20 mm) from 11.48% to 5.57% in this challenging retrospective data set. These approaches provided robustness to content mismatch and eliminated distinct failure modes of registration. Such improvement was gained without additional workflow and has motivated incorporation of the masking methods within a system under development for prospective clinical studies.

  2. Automatic masking for robust 3D-2D image registration in image-guided spine surgery

    NASA Astrophysics Data System (ADS)

    Ketcha, M. D.; De Silva, T.; Uneri, A.; Kleinszig, G.; Vogt, S.; Wolinsky, J.-P.; Siewerdsen, J. H.

    2016-03-01

    During spinal neurosurgery, patient-specific information, planning, and annotation such as vertebral labels can be mapped from preoperative 3D CT to intraoperative 2D radiographs via image-based 3D-2D registration. Such registration has been shown to provide a potentially valuable means of decision support in target localization as well as quality assurance of the surgical product. However, robust registration can be challenged by mismatch in image content between the preoperative CT and intraoperative radiographs, arising, for example, from anatomical deformation or the presence of surgical tools within the radiograph. In this work, we develop and evaluate methods for automatically mitigating the effect of content mismatch by leveraging the surgical planning data to assign greater weight to anatomical regions known to be reliable for registration and vital to the surgical task while removing problematic regions that are highly deformable or often occluded by surgical tools. We investigated two approaches to assigning variable weight (i.e., "masking") to image content and/or the similarity metric: (1) masking the preoperative 3D CT ("volumetric masking"); and (2) masking within the 2D similarity metric calculation ("projection masking"). The accuracy of registration was evaluated in terms of projection distance error (PDE) in 61 cases selected from an IRB-approved clinical study. The best performing of the masking techniques was found to reduce the rate of gross failure (PDE > 20 mm) from 11.48% to 5.57% in this challenging retrospective data set. These approaches provided robustness to content mismatch and eliminated distinct failure modes of registration. Such improvement was gained without additional workflow and has motivated incorporation of the masking methods within a system under development for prospective clinical studies.

  3. Surgical Navigation Technology Based on Augmented Reality and Integrated 3D Intraoperative Imaging: A Spine Cadaveric Feasibility and Accuracy Study.

    PubMed

    Elmi-Terander, Adrian; Skulason, Halldor; Söderman, Michael; Racadio, John; Homan, Robert; Babic, Drazenko; van der Vaart, Nijs; Nachabe, Rami

    2016-11-01

    A cadaveric laboratory study. The aim of this study was to assess the feasibility and accuracy of thoracic pedicle screw placement using augmented reality surgical navigation (ARSN). Recent advances in spinal navigation have shown improved accuracy in lumbosacral pedicle screw placement but limited benefits in the thoracic spine. 3D intraoperative imaging and instrument navigation may allow improved accuracy in pedicle screw placement, without the use of x-ray fluoroscopy, and thus opens the route to image-guided minimally invasive therapy in the thoracic spine. ARSN encompasses a surgical table, a motorized flat detector C-arm with intraoperative 2D/3D capabilities, integrated optical cameras for augmented reality navigation, and noninvasive patient motion tracking. Two neurosurgeons placed 94 pedicle screws in the thoracic spine of four cadavers using ARSN on one side of the spine (47 screws) and free-hand technique on the contralateral side. X-ray fluoroscopy was not used for either technique. Four independent reviewers assessed the postoperative scans, using the Gertzbein grading. Morphometric measurements of the pedicles axial and sagittal widths and angles, as well as the vertebrae axial and sagittal rotations were performed to identify risk factors for breaches. ARSN was feasible and superior to free-hand technique with respect to overall accuracy (85% vs. 64%, P < 0.05), specifically significant increases of perfectly placed screws (51% vs. 30%, P < 0.05) and reductions in breaches beyond 4 mm (2% vs. 25%, P < 0.05). All morphometric dimensions, except for vertebral body axial rotation, were risk factors for larger breaches when performed with the free-hand method. ARSN without fluoroscopy was feasible and demonstrated higher accuracy than free-hand technique for thoracic pedicle screw placement. N/A.

  4. Non-invasive methods for the determination of body and carcass composition in livestock: dual-energy X-ray absorptiometry, computed tomography, magnetic resonance imaging and ultrasound: invited review.

    PubMed

    Scholz, A M; Bünger, L; Kongsro, J; Baulain, U; Mitchell, A D

    2015-07-01

    The ability to accurately measure body or carcass composition is important for performance testing, grading and finally selection or payment of meat-producing animals. Advances especially in non-invasive techniques are mainly based on the development of electronic and computer-driven methods in order to provide objective phenotypic data. The preference for a specific technique depends on the target animal species or carcass, combined with technical and practical aspects such as accuracy, reliability, cost, portability, speed, ease of use, safety and for in vivo measurements the need for fixation or sedation. The techniques rely on specific device-driven signals, which interact with tissues in the body or carcass at the atomic or molecular level, resulting in secondary or attenuated signals detected by the instruments and analyzed quantitatively. The electromagnetic signal produced by the instrument may originate from mechanical energy such as sound waves (ultrasound - US), 'photon' radiation (X-ray-computed tomography - CT, dual-energy X-ray absorptiometry - DXA) or radio frequency waves (magnetic resonance imaging - MRI). The signals detected by the corresponding instruments are processed to measure, for example, tissue depths, areas, volumes or distributions of fat, muscle (water, protein) and partly bone or bone mineral. Among the above techniques, CT is the most accurate one followed by MRI and DXA, whereas US can be used for all sizes of farm animal species even under field conditions. CT, MRI and US can provide volume data, whereas only DXA delivers immediate whole-body composition results without (2D) image manipulation. A combination of simple US and more expensive CT, MRI or DXA might be applied for farm animal selection programs in a stepwise approach.

  5. Effective dose reduction in spine radiographic imaging by choosing the less radiation-sensitive side of the body.

    PubMed

    Ben-Shlomo, Avi; Bartal, Gabriel; Mosseri, Morris; Avraham, Boaz; Leitner, Yosef; Shabat, Shay

    2016-04-01

    X-ray absorption is highest in the organs and tissues located closest to the radiation source. The photon flux that crosses the body decreases from the entry surface toward the image receptor. The internal organs absorb x-rays and shield each other during irradiation. Therefore, changing the x-ray projection angle relative to the patient for specific spine procedures changes the radiation dose that each organ receives. Every organ has different radiation sensitivity, so irradiation from different sides of the body changes the biological influence and radiation risk potential on the total body, that is the effective dose (ED). The study aimed to determine the less radiation-sensitive sides of the body during lateral and anterior-posterior (AP) or posterior anterior (PA) directions. The study used exposure of patient phantoms and Monte Carlo simulation of the effective doses. Calculations for adults and 10-year-old children were included because the pediatric population has a greater lifetime radiation risk than adults. Pediatric and adult tissue and organ doses and ED from cervical, thoracic, and lumbar x-ray spine examinations were performed from different projections. Standard mathematical phantoms for adults and 10-year-old children, using PCXMC 2.0 software based on Monte Carlo simulations, were used to calculate pediatric and adult tissue and organ doses and ED. The study was not funded. The authors have no conflicts of interest to declare. Spine x-ray exposure from various right (RT) LAT projection angles was associated with lower ED compared with the same left (LT) LAT projections (up to 28% and 27% less for children aged 10 and adults, respectively). The PA spine projections showed up to 64% lower ED for children aged 10 and 65% for adults than AP projections. The AP projection at the thoracic spine causes an excess breast dose of 543.3% and 597.0% for children aged 10 and adults, respectively. Radiation ED in spine procedures can be significantly reduced by

  6. Elimination of motion, pulsatile flow and cross-talk artifacts using blade sequences in lumbar spine MR imaging.

    PubMed

    Lavdas, Eleftherios; Mavroidis, Panayiotis; Kostopoulos, Spiros; Glotsos, Dimitrios; Roka, Violeta; Koutsiaris, Aristotle G; Batsikas, Georgios; Sakkas, Georgios K; Tsagkalis, Antonios; Notaras, Ioannis; Stathakis, Sotirios; Papanikolaou, Nikos; Vassiou, Katerina

    2013-07-01

    The purpose of this study is to evaluate the ability of T2 turbo spin echo (TSE) axial and sagittal BLADE sequences in reducing or even eliminating motion, pulsatile flow and cross-talk artifacts in lumbar spine MRI examinations. Forty four patients, who had routinely undergone a lumbar spine examination, participated in the study. The following pairs of sequences with and without BLADE were compared: a) T2 TSE Sagittal (SAG) in thirty two cases, and b) T2 TSE Axial (AX) also in thirty two cases. Both quantitative and qualitative analyses were performed based on measurements in different normal anatomical structures and examination of seven characteristics, respectively. The qualitative analysis was performed by experienced radiologists. Also, the presence of image motion, pulsatile flow and cross-talk artifacts was evaluated. Based on the results of the qualitative analysis for the different sequences and anatomical structures, the BLADE sequences were found to be significantly superior to the conventional ones in all the cases. The BLADE sequences eliminated the motion artifacts in all the cases. In our results, it was found that in the examined sequences (sagittal and axial) the differences between the BLADE and conventional sequences regarding the elimination of motion, pulsatile flow and cross-talk artifacts were statistically significant. In all the comparisons, the T2 TSE BLADE sequences were significantly superior to the corresponding conventional sequences regarding the classification of their image quality. In conclusion, this technique appears to be capable of potentially eliminating motion, pulsatile flow and cross-talk artifacts in lumbar spine MR images and producing high quality images in collaborative and non-collaborative patients. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Changes in use of cervical spine magnetic resonance imaging for pediatric patients with nonaccidental trauma.

    PubMed

    Oh, Ahyuda; Sawvel, Michael; Heaner, David; Bhatia, Amina; Reisner, Andrew; Tubbs, R Shane; Chern, Joshua J

    2017-09-01

    OBJECTIVE Past studies have suggested correlations between abusive head trauma and concurrent cervical spine (c-spine) injury. Accordingly, c-spine MRI (cMRI) has been increasingly used in radiographic assessments. This study aimed to determine trends in cMRI use and treatment, and outcomes related to c-spine injury in children with nonaccidental trauma (NAT). METHODS A total of 503 patients with NAT who were treated between 2009 and 2014 at a single pediatric health care system were identified from a prospectively maintained database. Additional data on selected clinical events were retrospectively collected from electronic medical records. In 2012, a clinical pathway on cMRI usage for patients with NAT was implemented. The present study compared cMRI use and clinical outcomes between the prepathway (2009-2011) and postpathway (2012-2014) periods. RESULTS There were 249 patients in the prepathway and 254 in the postpathway groups. Incidences of cranial injury and Injury Severity Scores were not significantly different between the 2 groups. More patients underwent cMRI in the years after clinical pathway implementation than before (2.8% vs 33.1%, p < 0.0001). There was also a significant increase in cervical collar usage from 16.5% to 27.6% (p = 0.004), and more patients were discharged home with cervical collar immobilization. Surgical stabilization occurred in a single case in the postpathway group. CONCLUSIONS Heightened awareness of potential c-spine injury in this population increased the use of cMRI and cervical collar immobilization over a 6-year period. However, severe c-spine injury remains rare, and increased use of cMRI might not affect outcomes markedly.

  8. Comparison of Gross Body Fat-Water Magnetic Resonance Imaging at 3 Tesla to Dual Energy X-Ray Absorptiometry in Obese Women

    PubMed Central

    Silver, HJ; Niswender, KD; Kullberg, J; Berglund, J; Johansson, L; Bruvold, M; Avison, MJ; Welch, EB.

    2012-01-01

    Improved understanding of how depot-specific adipose tissue mass predisposes to obesity-related comorbidities could yield new insights into the pathogenesis and treatment of obesity as well as metabolic benefits of weight loss. We hypothesized that three-dimensional contiguous “fat-water” MR imaging (FWMRI) covering the majority of a whole-body field of view (FOV) acquired at 3 Tesla (3T) and coupled with automated segmentation and quantification of amount, type and distribution of adipose and lean soft tissue would show great promise in body composition methodology. Precision of adipose and lean soft tissue measurements in body and trunk regions were assessed for 3T FWMRI and compared to DEXA. Anthropometric, FWMRI and DEXA measurements were obtained in twelve women with BMI 30–39.9 kg/m2. Test-retest results found coefficients of variation for FWMRI that were all under 3%: gross body adipose tissue (GBAT) 0.80%, total trunk adipose tissue (TTAT) 2.08%, visceral adipose tissue (VAT) 2.62%, subcutaneous adipose tissue (SAT) 2.11%, gross body lean soft tissue (GBLST) 0.60%, and total trunk lean soft tissue (TTLST) 2.43%. Concordance correlation coefficients between FWMRI and DEXA were 0.978, 0.802, 0.629, and 0.400 for GBAT, TTAT, GBLST and TTLST, respectively. While Bland Altman plots demonstrated agreement between FWMRI and DEXA for GBAT and TTAT, a negative bias existed for GBLST and TTLST measurements. Differences may be explained by the FWMRI FOV length and potential for DEXA to overestimate lean soft tissue. While more development is necessary, the described 3T FWMRI method combined with fully-automated segmentation is fast (<30 minutes total scan and post-processing time), noninvasive, repeatable and cost effective. PMID:23712980

  9. The prediction of total skeletal muscle mass in a Caucasian population - comparison of Magnetic resonance imaging (MRI) and Dual-energy X-ray absorptiometry (DXA).

    PubMed

    Geisler, Corinna; Pourhassan, Maryam; Braun, Wiebke; Schweitzer, Lisa; Müller, Manfred J

    2017-03-01

    Dual-energy X-ray (DXA) is an alternative to magnetic resonance imaging (MRI) to measure skeletal muscle mass. DXA assesses lean body mass (LBM), and MRI measures skeletal muscle mass (SMM). Kim et al. (Am J Clin Nutr 2002; 76: 378; J Appl Physiol (1985) 2004; 97: 655) developed MRI-based algorithms to estimate whole-body SMM by DXA. These algorithms were based on an ethnically mixed study population (Kim et al., Am J Clin Nutr 2002; 76: 378; J Appl Physiol (1985) 2004; 97: 655). It is unclear whether Kim's algorithms are accurate in an exclusive Caucasian population. The aim of our study was to validate Kim's equation in a Caucasian population of 346 subjects. SMM MRI was assessed using MRI, and LBM and BMC DXA were measured by DXA and fat mass (FM ADP ) by air-displacement plethysmographie (ADP). SMM MRI and predicted SMM were highly correlated (r = 0·944; P<0·05). The standard error of estimate of the regression equation was 2·4 kg. However, Bland-Altman plots showed a significant (P<0·001) systematic bias between SMM MRI (median 25·1 kg; IQ 20·2-31·1 kg) and predicted SMM (median 26·3 kg; IQ 22·6-33·0 kg), overestimating SMM by 9·8%. Multiple regression analyses showed that weight explained 4·4% of the variance in the differences between SMM MRI and predicted SMM with the major part unexplained. Kim's algorithm has a systematic unexplained bias and is not recommended in Caucasians. © 2015 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  10. Interrater and intrarater agreements of magnetic resonance imaging findings in the lumbar spine: significant variability across degenerative conditions.

    PubMed

    Fu, Michael C; Buerba, Rafael A; Long, William D; Blizzard, Daniel J; Lischuk, Andrew W; Haims, Andrew H; Grauer, Jonathan N

    2014-10-01

    Magnetic resonance imaging (MRI) is frequently used in the evaluation of degenerative conditions in the lumbar spine. The relative interrater and intrarater agreements of MRI findings across different pathologic conditions are underexplored, as most studies are focused on specific findings. The purpose of this study was to characterize the interrater and intrarater agreements of MRI findings used to assess the degenerative lumbar spine. A retrospective diagnostic study at a large academic medical center was undertaken with a panel of orthopedic surgeons and musculoskeletal radiologists to assess lumbar MRIs using standardized criteria. Seventy-five subjects who underwent routine lumbar spine MRI at our institution were included. Each MRI study was assessed for 10 lumbar degenerative findings using standardized criteria. Lumbar vertebral levels were assessed independently, where applicable, for a total of 52 data points collected per study. T2-weighted axial and sagittal MRI sequences were presented in random order to the four reviewers (two orthopedic spine surgeons and two musculoskeletal radiologists) independently to determine interrater agreement. The first 10 studies were reevaluated at the end to determine intrarater agreement. Images were assessed using standardized and pilot-tested criteria to assess disc degeneration, stenosis, and other degenerative changes. Interrater and intrarater absolute percent agreements were calculated. To highlight the most clinically important MRI disagreements, a modified agreement analysis was also performed (in which disagreements between the lowest two severity grades for applicable conditions were ignored). Fleiss kappa coefficients for interrater agreement were determined. The overall absolute and modified interrater agreements were 76.9% and 93.5%, respectively. The absolute and modified intrarater agreements were 81.3% and 92.7%, respectively. Average Fleiss kappa coefficient was 0.431, suggesting moderate overall

  11. Is bone mineral density measurement using dual-energy X-ray absorptiometry affected by gamma rays?

    PubMed

    Xie, Liang-Jun; Li, Jian-Fang; Zeng, Feng-Wei; Jiang, Hang; Cheng, Mu-Hua; Chen, Yi

    2013-01-01

    The objective of this study was to determine whether the gamma rays emitted from the radionuclide effect bone mineral density (BMD) measurement. Nine subjects (mean age: 56 ± 17.96 yr) scheduled for bone scanning underwent BMD measurement using dual-energy X-ray absorptiometry (DXA) (Hologic/Discovery A) before and 1, 2, and 4 h after injection of technetium-99m-methylene diphosphonate (99mTc-MDP). Ten subjects (mean age: 41 ± 15.47 yr) scheduled for therapy of differentiated thyroid carcinoma with iodine-131 underwent BMD measurement before and 2 h after therapeutic radionuclide administration. All patients were given whole body BMD measurement, including head, arm, ribs, lumbar spine, pelvis, and leg sites. Besides, patients who referred to radioiodine therapy were given total hip and femoral neck BMD measurement as well. No statistically significant changes in BMD values were detected after 99mTc-MDP and iodine-131 administration for all measurement sites (p > 0.05), and individual difference of BMD before and after radionuclide imaging or therapy was less than the least significant change in lumbar spine, total hip, and femoral neck. In conclusion, BMD measurements are not influenced by the gamma rays emitted from technetium-99m and iodine-131. DXA bone densitometry may be performed simultaneously with bone scanning and radioiodine therapy. Copyright © 2013 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

  12. Interest of intra-operative 3D imaging in spine surgery: a prospective randomized study.

    PubMed

    Ruatti, Sébastien; Dubois, C; Chipon, E; Kerschbaumer, G; Milaire, M; Moreau-Gaudry, A; Tonetti, J; Merloz, Ph

    2016-06-01

    We report a single-center, prospective, randomized study for pedicle screw insertion in opened and percutaneous spine surgeries, using a computer-assisted surgery (CAS) technique with three-dimensional (3D) intra-operative images intensifier (without planification on pre-operative CT scan) vs conventional surgical procedure. We included 143 patients: Group C (conventional, 72 patients) and Group N (3D Fluoronavigation, 71 patients). We measured the pedicle screw running time, and surgeon's radiation exposure. All pedicle runs were assessed according to Heary by two independent radiologists on a post-operative CT scan. 3D Fluoronavigation appeared less accurate in percutaneous procedures (24 % of misplaced pedicle screws vs 5 % in Group C) (p = 0.007), but more accurate in opened surgeries (5 % of misplaced pedicle screws vs 17 % in Group C) (p = 0.025). For one vertebra, the average surgical running time reached 8 min in Group C vs 21 min in Group N for percutaneous surgeries (p = 3.42 × 10(-9)), 7.33 min in Group C vs 16.33 min in Group N (p = 2.88 × 10(-7)) for opened surgeries. The 3D navigation device delivered less radiation in percutaneous procedures [0.6 vs 1.62 mSv in Group C (p = 2.45 × 10(-9))]. For opened surgeries, it was twice higher in Group N with 0.21 vs 0.1 mSv in Group C (p = 0.022). The rate of misplaced pedicle screws with conventional techniques was nearly the same as most papers and a little bit higher with CAS. Surgical running time and radiation exposure were consistent with many studies. Our work hypothesis is partially confirmed, depending on the type of surgery (opened or closed procedure).

  13. Deformable registration for image-guided spine surgery: preserving rigid body vertebral morphology in free-form transformations

    NASA Astrophysics Data System (ADS)

    Reaungamornrat, S.; Wang, A. S.; Uneri, A.; Otake, Y.; Zhao, Z.; Khanna, A. J.; Siewerdsen, J. H.

    2014-03-01

    Purpose: Deformable registration of preoperative and intraoperative images facilitates accurate localization of target and critical anatomy in image-guided spine surgery. However, conventional deformable registration fails to preserve the morphology of rigid bone anatomy and can impart distortions that confound high-precision intervention. We propose a constrained registration method that preserves rigid morphology while allowing deformation of surrounding soft tissues. Method: The registration method aligns preoperative 3D CT to intraoperative cone-beam CT (CBCT) using free-form deformation (FFD) with penalties on rigid body motion imposed according to a simple intensity threshold. The penalties enforced 3 properties of a rigid transformation - namely, constraints on affinity (AC), orthogonality (OC), and properness (PC). The method also incorporated an injectivity constraint (IC) to preserve topology. Physical experiments (involving phantoms, an ovine spine, and a human cadaver) as well as digital simulations were performed to evaluate the sensitivity to registration parameters, preservation of rigid body morphology, and overall registration accuracy of constrained FFD in comparison to conventional unconstrained FFD (denoted uFFD) and Demons registration. Result: FFD with orthogonality and injectivity constraints (denoted FFD+OC+IC) demonstrated improved performance compared to uFFD and Demons. Affinity and properness constraints offered little or no additional improvement. The FFD+OC+IC method preserved rigid body morphology at near-ideal values of zero dilatation (D = 0.05, compared to 0.39 and 0.56 for uFFD and Demons, respectively) and shear (S = 0.08, compared to 0.36 and 0.44 for uFFD and Demons, respectively). Target registration error (TRE) was similarly improved for FFD+OC+IC (0.7 mm), compared to 1.4 and 1.8 mm for uFFD and Demons. Results were validated in human cadaver studies using CT and CBCT images, with FFD+OC+IC providing excellent preservation

  14. The Degenerative Spine.

    PubMed

    Clarençon, Frédéric; Law-Ye, Bruno; Bienvenot, Peggy; Cormier, Évelyne; Chiras, Jacques

    2016-08-01

    Degenerative disease of the spine is a leading cause of back pain and radiculopathy, and is a frequent indication for spine MR imaging. Disc degeneration, disc protrusion/herniation, discarhtrosis, spinal canal stenosis, and facet joint arthrosis, as well as interspinous processes arthrosis, may require an MR imaging workup. This review presents the MR imaging patterns of these diseases and describes the benefit of the MR imaging in these indications compared with the other imaging modalities like plain radiographs or computed tomography scan. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. The relationship between the magnetic resonance imaging appearance of the lumbar spine and low back pain, age and occupation in males.

    PubMed

    Savage, R A; Whitehouse, G H; Roberts, N

    1997-01-01

    The purpose of this study was to undertake a critical review of the potential role of magnetic resonance imaging (MRI) in the evaluation of low back pain (LBP) and to determine if there were differences in the MRI appearances between various occupational groups. The study group, 149 working men (78 aged 20-30 years and 71 aged 31-58 years) from five different occupations (car production workers, ambulance men, office staff, hospital porters and brewery draymen), underwent MRI of the lumbar spine. Thirty-four percent of the subjects had never experienced LBP. Twelve months later, the examination was repeated on 89 men. Age-related differences were seen in the MRI appearances of the lumbar spine. Disc degeneration was most common at L5/S1 and was significantly more prevalent (P < 0.01) in the older age group (52%) than in the younger age group (27%). Although LBP was more prevalent in the older subjects there was no relationship between LBP and disc degeneration. No differences in the MRI appearance of the lumbar spine were observed between the five occupational groups. Overall, 45% had 'abnormal' lumbar spines (evidence of disc degeneration, disc bulging or protrusion, facet hypertrophy, or nerve root compression). There was not a clear relationship between the MRI appearance of the lumbar spine and LBP. Thirty-two percent of asymptomatic subjects had 'abnormal' lumbar spines and 47% of all the subjects who had experienced LBP had 'normal' lumbar spines. During the 12-month follow-up period, 13 subjects experienced LBP for the first time. However, there was no change in the MRI appearances of their lumbar spines that could account for the onset of LBP. Although MRI is an excellent technique for evaluating the lumbar spine, this study shows that it does not provide a suitable pre-employment screening technique capable of identifying those at risk of LBP.

  16. High-field open versus short-bore magnetic resonance imaging of the spine: a randomized controlled comparison of image quality.

    PubMed

    Enders, Judith; Rief, Matthias; Zimmermann, Elke; Asbach, Patrick; Diederichs, Gerd; Wetz, Christoph; Siebert, Eberhard; Wagner, Moritz; Hamm, Bernd; Dewey, Marc

    2013-01-01

    The purpose of the present study was to compare the image quality of spinal magnetic resonance (MR) imaging performed on a high-field horizontal open versus a short-bore MR scanner in a randomized controlled study setup. Altogether, 93 (80% women, mean age 53) consecutive patients underwent spine imaging after random assignement to a 1-T horizontal open MR scanner with a vertical magnetic field or a 1.5-T short-bore MR scanner. This patient subset was part of a larger cohort. Image quality was assessed by determining qualitative parameters, signal-to-noise (SNR) and contrast-to-noise ratios (CNR), and quantitative contour sharpness. The image quality parameters were higher for short-bore MR imaging. Regarding all sequences, the relative differences were 39% for the mean overall qualitative image quality, 53% for the mean SNR values, and 34-37% for the quantitative contour sharpness (P<0.0001). The CNR values were also higher for images obtained with the short-bore MR scanner. No sequence was of very poor (nondiagnostic) image quality. Scanning times were significantly longer for examinations performed on the open MR scanner (mean: 32±22 min versus 20±9 min; P<0.0001). In this randomized controlled comparison of spinal MR imaging with an open versus a short-bore scanner, short-bore MR imaging revealed considerably higher image quality with shorter scanning times. ClinicalTrials.gov NCT00715806.

  17. High-Field Open versus Short-Bore Magnetic Resonance Imaging of the Spine: A Randomized Controlled Comparison of Image Quality

    PubMed Central

    Zimmermann, Elke; Asbach, Patrick; Diederichs, Gerd; Wetz, Christoph; Siebert, Eberhard; Wagner, Moritz; Hamm, Bernd; Dewey, Marc

    2013-01-01

    Background The purpose of the present study was to compare the image quality of spinal magnetic resonance (MR) imaging performed on a high-field horizontal open versus a short-bore MR scanner in a randomized controlled study setup. Methods Altogether, 93 (80% women, mean age 53) consecutive patients underwent spine imaging after random assignement to a 1-T horizontal open MR scanner with a vertical magnetic field or a 1.5-T short-bore MR scanner. This patient subset was part of a larger cohort. Image quality was assessed by determining qualitative parameters, signal-to-noise (SNR) and contrast-to-noise ratios (CNR), and quantitative contour sharpness. Results The image quality parameters were higher for short-bore MR imaging. Regarding all sequences, the relative differences were 39% for the mean overall qualitative image quality, 53% for the mean SNR values, and 34–37% for the quantitative contour sharpness (P<0.0001). The CNR values were also higher for images obtained with the short-bore MR scanner. No sequence was of very poor (nondiagnostic) image quality. Scanning times were significantly longer for examinations performed on the open MR scanner (mean: 32±22 min versus 20±9 min; P<0.0001). Conclusions In this randomized controlled comparison of spinal MR imaging with an open versus a short-bore scanner, short-bore MR imaging revealed considerably higher image quality with shorter scanning times. Trial Registration ClinicalTrials.gov NCT00715806 PMID:24391767

  18. Effectiveness of Implementing Evidence-based Interventions to Reduce C-spine Image Ordering in the Emergency Department: A Systematic Review.

    PubMed

    Desai, Shashwat; Liu, Chaocheng; Kirkland, Scott W; Krebs, Lynette D; Keto-Lambert, Diana; Rowe, Brian H

    2018-06-01

    Appropriate use of imaging for adult patients with cervical spine (C-spine) injuries in the emergency department (ED) is a longstanding issue. Guidance for C-spine ordering exists; however, the effectiveness of the decision support implementation in the ED is not well studied. This systematic review examines the implementation and effectiveness of evidence-based interventions aimed at reducing C-spine imaging in adults presenting to the ED with neck trauma. Six electronic databases and the gray literature were searched. Comparative intervention studies were eligible for inclusion. Two independent reviewers screened for study eligibility, study quality, and extracted data. The change in imaging was reported using individual odds ratios (ORs) with 95% confidence intervals (CIs) using random effects. A total of 990 unique citations were screened for relevance of which six before-after studies and one randomized controlled trial were included. None of the studies were assessed as high quality. Interventions consisted primarily of locally developed guidelines or established clinical decision rules such as the NEXUS or the Canadian C-spine rule. Overall, implementation of interventions aimed at reducing C-spine image ordering resulted in a statistically significant reduction in imaging (OR = 0.69, 95% CI = 0.51-0.93); however, heterogeneity was high (I 2  = 82%). Subgroup analysis revealed no differences between studies that specified enrolling alert and stable patients compared to unspecified trauma (p = 0.81) or between studies employing multifaceted versus nonmultifaceted interventions (p = 0.66). While studies generally provided details on implementation strategies (e.g., teaching sessions, pocket cards, posters, computerized decision support) the effectiveness of these implementation strategies were frequently not reported. There is moderate evidence regarding the effectiveness of interventions to reduce C-spine image ordering in adult patients seen in the

  19. In vivo body composition in autochthonous and conventional pig breeding groups by dual-energy X-ray absorptiometry and magnetic resonance imaging under special consideration of Cerdo Ibérico.

    PubMed

    Kremer, P V; Fernández-Fígares, I; Förster, M; Scholz, A M

    2012-12-01

    The improvement of carcass quality is one of the main breeding goals in pig production. To select appropriate breeding animals, it is of major concern to exactly and reliably analyze the body composition in vivo. Therefore, the objective of the study was to examine whether the combination of dual-energy X-ray absorptiometry (DXA) and magnetic resonance imaging (MRI) offers the opportunity to reliably analyze quantitative and qualitative body composition characteristics of different pig breeding groups in vivo. In this study, a total of 77 pigs were studied by DXA and MRI at an average age of 154 days. The pigs originated from different autochthonous or conventional breeds or crossbreeds and were grouped into six breed types: Cerdo Ibérico (Ib); Duroc × Ib (Du_Ib); White Sow Lines (WSL, including German Landrace and German Large White); Hampshire/Pietrain (Pi_Ha, including Hampshire, Pietrain × Hampshire (PiHa) and Pietrain × PiHa); Pietrain/Duroc (Pi_Du, including Pietrain × Duroc (PiDu) and Pietrain × PiDu); crossbred WSL (PiDu_WSL, including Pietrain × WSL and PiDu × WSL). A whole-body scan was performed by DXA with a GE Lunar DPX-IQ in order to measure the amount and percentage of fat tissue (FM; %FM), lean tissue (LM; %LM) and bone mineral, whereas a Siemens Magnetom Open with a large body coil was used for MRI in the thorax region between 13th and 14th vertebrae in order to measure the area of the loin (LA) and the above back fat area (FA) of both body sides. A GLM procedure using SAS 9.2 was used to analyze the data. As expected, the native breed Ib followed by Du_Ib crossbreeds showed the highest %FM (27.2%, 25.0%) combined with the smallest LA (46.2 cm2, 73.6 cm2), whereas Ib had the lowest BW at an average age of 154 days. Pigs with Pi_Ha origin presented the least %FM (12.4%) and largest LA (99.5 cm2). The WSL and PiDu_WSL showed an intermediate body composition. Therefore, it could be concluded that DXA and MRI and especially their combination

  20. Fully automatic and reference-marker-free image stitching method for full-spine and full-leg imaging with computed radiography

    NASA Astrophysics Data System (ADS)

    Wang, Xiaohui; Foos, David H.; Doran, James; Rogers, Michael K.

    2004-05-01

    Full-leg and full-spine imaging with standard computed radiography (CR) systems requires several cassettes/storage phosphor screens to be placed in a staggered arrangement and exposed simultaneously to achieve an increased imaging area. A method has been developed that can automatically and accurately stitch the acquired sub-images without relying on any external reference markers. It can detect and correct the order, orientation, and overlap arrangement of the subimages for stitching. The automatic determination of the order, orientation, and overlap arrangement of the sub-images consists of (1) constructing a hypothesis list that includes all cassette/screen arrangements, (2) refining hypotheses based on a set of rules derived from imaging physics, (3) correlating each consecutive sub-image pair in each hypothesis and establishing an overall figure-of-merit, (4) selecting the hypothesis of maximum figure-of-merit. The stitching process requires the CR reader to over scan each CR screen so that the screen edges are completely visible in the acquired sub-images. The rotational displacement and vertical displacement between two consecutive sub-images are calculated by matching the orientation and location of the screen edge in the front image and its corresponding shadow in the back image. The horizontal displacement is estimated by maximizing the correlation function between the two image sections in the overlap region. Accordingly, the two images are stitched together. This process is repeated for the newly stitched composite image and the next consecutive sub-image until a full-image composite is created. The method has been evaluated in both phantom experiments and clinical studies. The standard deviation of image misregistration is below one image pixel.

  1. Assessment of nerve involvement in the lumbar spine: agreement between magnetic resonance imaging, physical examination and pain drawing findings

    PubMed Central

    2010-01-01

    Background Detection of nerve involvement originating in the spine is a primary concern in the assessment of spine symptoms. Magnetic resonance imaging (MRI) has become the diagnostic method of choice for this detection. However, the agreement between MRI and other diagnostic methods for detecting nerve involvement has not been fully evaluated. The aim of this diagnostic study was to evaluate the agreement between nerve involvement visible in MRI and findings of nerve involvement detected in a structured physical examination and a simplified pain drawing. Methods Sixty-one consecutive patients referred for MRI of the lumbar spine were - without knowledge of MRI findings - assessed for nerve involvement with a simplified pain drawing and a structured physical examination. Agreement between findings was calculated as overall agreement, the p value for McNemar's exact test, specificity, sensitivity, and positive and negative predictive values. Results MRI-visible nerve involvement was significantly less common than, and showed weak agreement with, physical examination and pain drawing findings of nerve involvement in corresponding body segments. In spine segment L4-5, where most findings of nerve involvement were detected, the mean sensitivity of MRI-visible nerve involvement to a positive neurological test in the physical examination ranged from 16-37%. The mean specificity of MRI-visible nerve involvement in the same segment ranged from 61-77%. Positive and negative predictive values of MRI-visible nerve involvement in segment L4-5 ranged from 22-78% and 28-56% respectively. Conclusion In patients with long-standing nerve root symptoms referred for lumbar MRI, MRI-visible nerve involvement significantly underestimates the presence of nerve involvement detected by a physical examination and a pain drawing. A structured physical examination and a simplified pain drawing may reveal that many patients with "MRI-invisible" lumbar symptoms need treatment aimed at nerve

  2. Intraoperative evaluation of device placement in spine surgery using known-component 3D-2D image registration

    NASA Astrophysics Data System (ADS)

    Uneri, A.; De Silva, T.; Goerres, J.; Jacobson, M. W.; Ketcha, M. D.; Reaungamornrat, S.; Kleinszig, G.; Vogt, S.; Khanna, A. J.; Osgood, G. M.; Wolinsky, J.-P.; Siewerdsen, J. H.

    2017-04-01

    Intraoperative x-ray radiography/fluoroscopy is commonly used to assess the placement of surgical devices in the operating room (e.g. spine pedicle screws), but qualitative interpretation can fail to reliably detect suboptimal delivery and/or breach of adjacent critical structures. We present a 3D-2D image registration method wherein intraoperative radiographs are leveraged in combination with prior knowledge of the patient and surgical components for quantitative assessment of device placement and more rigorous quality assurance (QA) of the surgical product. The algorithm is based on known-component registration (KC-Reg) in which patient-specific preoperative CT and parametric component models are used. The registration performs optimization of gradient similarity, removes the need for offline geometric calibration of the C-arm, and simultaneously solves for multiple component bodies, thereby allowing QA in a single step (e.g. spinal construct with 4-20 screws). Performance was tested in a spine phantom, and first clinical results are reported for QA of transpedicle screws delivered in a patient undergoing thoracolumbar spine surgery. Simultaneous registration of ten pedicle screws (five contralateral pairs) demonstrated mean target registration error (TRE) of 1.1  ±  0.1 mm at the screw tip and 0.7  ±  0.4° in angulation when a prior geometric calibration was used. The calibration-free formulation, with the aid of component collision constraints, achieved TRE of 1.4  ±  0.6 mm. In all cases, a statistically significant improvement (p  <  0.05) was observed for the simultaneous solutions in comparison to previously reported sequential solution of individual components. Initial application in clinical data in spine surgery demonstrated TRE of 2.7  ±  2.6 mm and 1.5  ±  0.8°. The KC-Reg algorithm offers an independent check and quantitative QA of the surgical product using radiographic/fluoroscopic views

  3. Assessment of nerve involvement in the lumbar spine: agreement between magnetic resonance imaging, physical examination and pain drawing findings.

    PubMed

    Bertilson, Bo C; Brosjö, Eva; Billing, Hans; Strender, Lars-Erik

    2010-09-10

    Detection of nerve involvement originating in the spine is a primary concern in the assessment of spine symptoms. Magnetic resonance imaging (MRI) has become the diagnostic method of choice for this detection. However, the agreement between MRI and other diagnostic methods for detecting nerve involvement has not been fully evaluated. The aim of this diagnostic study was to evaluate the agreement between nerve involvement visible in MRI and findings of nerve involvement detected in a structured physical examination and a simplified pain drawing. Sixty-one consecutive patients referred for MRI of the lumbar spine were - without knowledge of MRI findings - assessed for nerve involvement with a simplified pain drawing and a structured physical examination. Agreement between findings was calculated as overall agreement, the p value for McNemar's exact test, specificity, sensitivity, and positive and negative predictive values. MRI-visible nerve involvement was significantly less common than, and showed weak agreement with, physical examination and pain drawing findings of nerve involvement in corresponding body segments. In spine segment L4-5, where most findings of nerve involvement were detected, the mean sensitivity of MRI-visible nerve involvement to a positive neurological test in the physical examination ranged from 16-37%. The mean specificity of MRI-visible nerve involvement in the same segment ranged from 61-77%. Positive and negative predictive values of MRI-visible nerve involvement in segment L4-5 ranged from 22-78% and 28-56% respectively. In patients with long-standing nerve root symptoms referred for lumbar MRI, MRI-visible nerve involvement significantly underestimates the presence of nerve involvement detected by a physical examination and a pain drawing. A structured physical examination and a simplified pain drawing may reveal that many patients with "MRI-invisible" lumbar symptoms need treatment aimed at nerve involvement. Factors other than present

  4. SAR Reduction in 7T C-Spine Imaging Using a “Dark Modes” Transmit Array Strategy

    PubMed Central

    Eryaman, Yigitcan; Guerin, Bastien; Keil, Boris; Mareyam, Azma; Herraiz, Joaquin L.; Kosior, Robert K.; Martin, Adrian; Torrado-Carvajal, Angel; Malpica, Norberto; Hernandez-Tamames, Juan A.; Schiavi, Emanuele; Adalsteinsson, Elfar; Wald, Lawrence L.

    2016-01-01

    Purpose Local specific absorption rate (SAR) limits many applications of parallel transmit (pTx) in ultra high-field imaging. In this Note, we introduce the use of an array element, which is intentionally inefficient at generating spin excitation (a “dark mode”) to attempt a partial cancellation of the electric field from those elements that do generate excitation. We show that adding dipole elements oriented orthogonal to their conventional orientation to a linear array of conventional loop elements can lower the local SAR hotspot in a C-spine array at 7 T. Methods We model electromagnetic fields in a head/torso model to calculate SAR and excitation B1+ patterns generated by conventional loop arrays and loop arrays with added electric dipole elements. We utilize the dark modes that are generated by the intentional and inefficient orientation of dipole elements in order to reduce peak 10g local SAR while maintaining excitation fidelity. Results For B1+ shimming in the spine, the addition of dipole elements did not significantly alter the B1+ spatial pattern but reduced local SAR by 36%. Conclusion The dipole elements provide a sufficiently complimentary B1+ and electric field pattern to the loop array that can be exploited by the radiofrequency shimming algorithm to reduce local SAR. PMID:24753012

  5. A comparison of MRI and CT imaging clarity of titanium alloy and titanium alloy with cobalt-chromium-alloy pedicle screw and rod implants in the lumbar spine.

    PubMed

    Trammell, Terry R; Flint, Kathy; Ramsey, Curtis J

    2012-08-15

    Magnetic resonance imaging (MRI) and computed tomography (CT) imaging are important postoperative diagnostic and evaluation tools, particularly in patients who have undergone spinal fusions. Advancements in materials and imaging techniques have lessened artifact and improved overall imaging results. Systems that combine titanium alloy and cobalt-chromium components have been introduced to reduce implant profile while maintaining strength. The objective of this study was to determine if there were any differences in the clarity of imaging between two types of implant materials in a lumbar spine construct model. One of two lumbar spine stabilization implant systems, titanium alloy (titanium) or titanium alloy with cobalt-chromium alloy (titanium-cobalt), was placed to simulate a four-level fusion construct in two human cadaveric spine segments, followed by MRI and CT imaging. The implant systems were then removed from each cadaver and implanted in the other cadaver. Nine physician graders from three subspecialties scored the images using a 5-point scale, with higher imaging scores indicating greater clarity of the region of interest. Physician-rated scores were compared across systems and between physician groups. There were no significant differences in the overall mean total scores on the basis of construct material. Overall mean scores were 18.16 for titanium and 17.45 for titanium-cobalt (p = 0.275). Among images of the titanium-cobalt constructs, no significant differences in mean scores were found between specimens with use of MRI (p = 0.883) or with use of CT only (p = 0.274). Among images of the titanium system, a slightly significant difference was found between specimens with use of MRI (p = 0.044) but not with CT imaging (p = 0.837). Overall image clarity scores were not significantly different between titanium and titanium-cobalt implant systems in the lumbar spine. Observation of pertinent anatomy in the regions of interest was not degraded by the

  6. Utility of magnetic resonance imaging in diagnosing cervical spine injury in children with severe traumatic brain injury.

    PubMed

    Qualls, David; Leonard, Jeffrey R; Keller, Martin; Pineda, Jose; Leonard, Julie C

    2015-06-01

    Evaluation of children for cervical spine injuries (CSIs) after blunt trauma is complicated, particularly if the patient is unresponsive because of severe traumatic brain injury. Plain radiography and computed tomography (CT) are commonly used, but CT combined with magnetic resonance imaging (MRI) is still considered the gold standard in CSI detection. However, MRI is expensive and can delay cervical clearance. The purpose of this study is to determine the added benefit of MRI as an adjunct to CT in the clearance of children with severe head trauma. We performed a retrospective chart review of pediatric head trauma patients admitted to the pediatric intensive care unit at St. Louis Children's Hospital from 2002 to 2012. Patients who received both cervical spine CT and MRI and presented with a Glasgow Coma Scale score of 8 or lower were included in the study. Imaging was analyzed by two pediatric trauma subspecialists and classified as demonstrating "no injury," "stable injury," or "unstable injury." Results were compared, and discrepancies between CT and MRI findings were noted. A total of 1,196 head-injured children were admitted to the pediatric intensive care unit between January 2002 and December 2012. Sixty-three children underwent CT and MRI and met Glasgow Coma Scale criteria. Seven children were identified with negative CT and positive MRI findings, but none of these injuries were considered unstable by our criteria. Five children were determined to have unstable injuries, and all were detected on CT. The results of this study suggest that MRI does not detect unstable CSIs in the setting of negative CT imaging. Given the limited patient population for this study, further and more extensive studies investigating the utility of MRI in the head-injured pediatric patient are warranted. Diagnostic and care management study, level IV.

  7. Two-Photon Functional Imaging of the Auditory Cortex in Behaving Mice: From Neural Networks to Single Spines.

    PubMed

    Li, Ruijie; Wang, Meng; Yao, Jiwei; Liang, Shanshan; Liao, Xiang; Yang, Mengke; Zhang, Jianxiong; Yan, Junan; Jia, Hongbo; Chen, Xiaowei; Li, Xingyi

    2018-01-01

    In vivo two-photon Ca 2+ imaging is a powerful tool for recording neuronal activities during perceptual tasks and has been increasingly applied to behaving animals for acute or chronic experiments. However, the auditory cortex is not easily accessible to imaging because of the abundant temporal muscles, arteries around the ears and their lateral locations. Here, we report a protocol for two-photon Ca 2+ imaging in the auditory cortex of head-fixed behaving mice. By using a custom-made head fixation apparatus and a head-rotated fixation procedure, we achieved two-photon imaging and in combination with targeted cell-attached recordings of auditory cortical neurons in behaving mice. Using synthetic Ca 2+ indicators, we recorded the Ca 2+ transients at multiple scales, including neuronal populations, single neurons, dendrites and single spines, in auditory cortex during behavior. Furthermore, using genetically encoded Ca 2+ indicators (GECIs), we monitored the neuronal dynamics over days throughout the process of associative learning. Therefore, we achieved two-photon functional imaging at multiple scales in auditory cortex of behaving mice, which extends the tool box for investigating the neural basis of audition-related behaviors.

  8. Two-Photon Functional Imaging of the Auditory Cortex in Behaving Mice: From Neural Networks to Single Spines

    PubMed Central

    Li, Ruijie; Wang, Meng; Yao, Jiwei; Liang, Shanshan; Liao, Xiang; Yang, Mengke; Zhang, Jianxiong; Yan, Junan; Jia, Hongbo; Chen, Xiaowei; Li, Xingyi

    2018-01-01

    In vivo two-photon Ca2+ imaging is a powerful tool for recording neuronal activities during perceptual tasks and has been increasingly applied to behaving animals for acute or chronic experiments. However, the auditory cortex is not easily accessible to imaging because of the abundant temporal muscles, arteries around the ears and their lateral locations. Here, we report a protocol for two-photon Ca2+ imaging in the auditory cortex of head-fixed behaving mice. By using a custom-made head fixation apparatus and a head-rotated fixation procedure, we achieved two-photon imaging and in combination with targeted cell-attached recordings of auditory cortical neurons in behaving mice. Using synthetic Ca2+ indicators, we recorded the Ca2+ transients at multiple scales, including neuronal populations, single neurons, dendrites and single spines, in auditory cortex during behavior. Furthermore, using genetically encoded Ca2+ indicators (GECIs), we monitored the neuronal dynamics over days throughout the process of associative learning. Therefore, we achieved two-photon functional imaging at multiple scales in auditory cortex of behaving mice, which extends the tool box for investigating the neural basis of audition-related behaviors. PMID:29740289

  9. Parametric modeling of the intervertebral disc space in 3D: application to CT images of the lumbar spine.

    PubMed

    Korez, Robert; Likar, Boštjan; Pernuš, Franjo; Vrtovec, Tomaž

    2014-10-01

    Gradual degeneration of intervertebral discs of the lumbar spine is one of the most common causes of low back pain. Although conservative treatment for low back pain may provide relief to most individuals, surgical intervention may be required for individuals with significant continuing symptoms, which is usually performed by replacing the degenerated intervertebral disc with an artificial implant. For designing implants with good bone contact and continuous force distribution, the morphology of the intervertebral disc space and vertebral body endplates is of considerable importance. In this study, we propose a method for parametric modeling of the intervertebral disc space in three dimensions (3D) and show its application to computed tomography (CT) images of the lumbar spine. The initial 3D model of the intervertebral disc space is generated according to the superquadric approach and therefore represented by a truncated elliptical cone, which is initialized by parameters obtained from 3D models of adjacent vertebral bodies. In an optimization procedure, the 3D model of the intervertebral disc space is incrementally deformed by adding parameters that provide a more detailed morphometric description of the observed shape, and aligned to the observed intervertebral disc space in the 3D image. By applying the proposed method to CT images of 20 lumbar spines, the shape and pose of each of the 100 intervertebral disc spaces were represented by a 3D parametric model. The resulting mean (±standard deviation) accuracy of modeling was 1.06±0.98mm in terms of radial Euclidean distance against manually defined ground truth points, with the corresponding success rate of 93% (i.e. 93 out of 100 intervertebral disc spaces were modeled successfully). As the resulting 3D models provide a description of the shape of intervertebral disc spaces in a complete parametric form, morphometric analysis was straightforwardly enabled and allowed the computation of the corresponding

  10. Robust 3D-2D image registration: application to spine interventions and vertebral labeling in the presence of anatomical deformation

    NASA Astrophysics Data System (ADS)

    Otake, Yoshito; Wang, Adam S.; Webster Stayman, J.; Uneri, Ali; Kleinszig, Gerhard; Vogt, Sebastian; Khanna, A. Jay; Gokaslan, Ziya L.; Siewerdsen, Jeffrey H.

    2013-12-01

    We present a framework for robustly estimating registration between a 3D volume image and a 2D projection image and evaluate its precision and robustness in spine interventions for vertebral localization in the presence of anatomical deformation. The framework employs a normalized gradient information similarity metric and multi-start covariance matrix adaptation evolution strategy optimization with local-restarts, which provided improved robustness against deformation and content mismatch. The parallelized implementation allowed orders-of-magnitude acceleration in computation time and improved the robustness of registration via multi-start global optimization. Experiments involved a cadaver specimen and two CT datasets (supine and prone) and 36 C-arm fluoroscopy images acquired with the specimen in four positions (supine, prone, supine with lordosis, prone with kyphosis), three regions (thoracic, abdominal, and lumbar), and three levels of geometric magnification (1.7, 2.0, 2.4). Registration accuracy was evaluated in terms of projection distance error (PDE) between the estimated and true target points in the projection image, including 14 400 random trials (200 trials on the 72 registration scenarios) with initialization error up to ±200 mm and ±10°. The resulting median PDE was better than 0.1 mm in all cases, depending somewhat on the resolution of input CT and fluoroscopy images. The cadaver experiments illustrated the tradeoff between robustness and computation time, yielding a success rate of 99.993% in vertebral labeling (with ‘success’ defined as PDE <5 mm) using 1,718 664 ± 96 582 function evaluations computed in 54.0 ± 3.5 s on a mid-range GPU (nVidia, GeForce GTX690). Parameters yielding a faster search (e.g., fewer multi-starts) reduced robustness under conditions of large deformation and poor initialization (99.535% success for the same data registered in 13.1 s), but given good initialization (e.g., ±5 mm, assuming a robust initial

  11. Understanding how axial loads on the spine influence segmental biomechanics for idiopathic scoliosis patients: A magnetic resonance imaging study.

    PubMed

    Little, J P; Pearcy, M J; Izatt, M T; Boom, K; Labrom, R D; Askin, G N; Adam, C J

    2016-02-01

    Segmental biomechanics of the scoliotic spine are important since the overall spinal deformity is comprised of the cumulative coronal and axial rotations of individual joints. This study investigates the coronal plane segmental biomechanics for adolescent idiopathic scoliosis patients in response to physiologically relevant axial compression. Individual spinal joint compliance in the coronal plane was measured for a series of 15 idiopathic scoliosis patients using axially loaded magnetic resonance imaging. Each patient was first imaged in the supine position with no axial load, and then again following application of an axial compressive load. Coronal plane disc wedge angles in the unloaded and loaded configurations were measured. Joint moments exerted by the axial compressive load were used to derive estimates of individual joint compliance. The mean standing major Cobb angle for this patient series was 46°. Mean intra-observer measurement error for endplate inclination was 1.6°. Following loading, initially highly wedged discs demonstrated a smaller change in wedge angle, than less wedged discs for certain spinal levels (+2,+1,-2 relative to the apex, (p<0.05)). Highly wedged discs were observed near the apex of the curve, which corresponded to lower joint compliance in the apical region. While individual patients exhibit substantial variability in disc wedge angles and joint compliance, overall there is a pattern of increased disc wedging near the curve apex, and reduced joint compliance in this region. Approaches such as this can provide valuable biomechanical data on in vivo spinal biomechanics of the scoliotic spine, for analysis of deformity progression and surgical planning. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Image analysis of open-door laminoplasty for cervical spondylotic myelopathy: comparing the influence of cord morphology and spine alignment.

    PubMed

    Lin, Bon-Jour; Lin, Meng-Chi; Lin, Chin; Lee, Meei-Shyuan; Feng, Shao-Wei; Ju, Da-Tong; Ma, Hsin-I; Liu, Ming-Ying; Hueng, Dueng-Yuan

    2015-10-01

    Previous studies have identified the factors affecting the surgical outcome of cervical spondylotic myelopathy (CSM) following laminoplasty. Nonetheless, the effect of these factors remains controversial. It is unknown about the association between pre-operative cervical spinal cord morphology and post-operative imaging result following laminoplasty. The goal of this study is to analyze the impact of pre-operative cervical spinal cord morphology on post-operative imaging in patients with CSM. Twenty-six patients with CSM undergoing open-door laminoplasty were classified according to pre-operative cervical spine bony alignment and cervical spinal cord morphology, and the results were evaluated in terms of post-operative spinal cord posterior drift, and post-operative expansion of the antero-posterior dura diameter. By the result of study, pre-operative spinal cord morphology was an effective classification in predicting surgical outcome - patients with anterior convexity type, description of cervical spinal cord morphology, had more spinal cord posterior migration than those with neutral or posterior convexity type after open-door laminoplasty. Otherwise, the interesting finding was that cervical spine Cobb's angle had an impact on post-operative spinal cord posterior drift in patients with neutral or posterior convexity type spinal cord morphology - the degree of kyphosis was inversely proportional to the distance of post-operative spinal cord posterior drift, but not in the anterior convexity type. These findings supported that pre-operative cervical spinal cord morphology may be used as screening for patients undergoing laminoplasty. Patients having neutral or posterior convexity type spinal cord morphology accompanied with kyphotic deformity were not suitable candidates for laminoplasty. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Positional Magnetic Resonance Imaging for People With Ehlers-Danlos Syndrome or Suspected Craniovertebral or Cervical Spine Abnormalities: An Evidence-Based Analysis

    PubMed Central

    2015-01-01

    Background Ehlers-Danlos syndrome (EDS) is an inherited disorder affecting the connective tissue. EDS can manifest with symptoms attributable to the spine or craniovertebral junction (CVJ). In addition to EDS, numerous congenital, developmental, or acquired disorders can increase ligamentous laxity in the CVJ and cervical spine. Resulting abnormalities can lead to morbidity and serious neurologic complications. Appropriate imaging and diagnosis is needed to determine patient management and need for complex surgery. Some spinal abnormalities cause symptoms or are more pronounced while patients sit, stand, or perform specific movements. Positional magnetic resonance imaging (pMRI) allows imaging of the spine or CVJ with patients in upright, weight-bearing positions and can be combined with dynamic maneuvers, such as flexion, extension, or rotation. Imaging in these positions could allow diagnosticians to better detect spinal or CVJ abnormalities than recumbent MRI or even a combination of other available imaging modalities might allow. Objectives To determine the diagnostic impact and clinical utility of pMRI for the assessment of (a) craniovertebral or spinal abnormalities among people with EDS and (b) major craniovertebral or cervical spine abnormalities among symptomatic people. Data Sources A literature search was performed using Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid Embase, and EBM Reviews, for studies published from January 1, 1998, to September 28, 2014. Review Methods Studies comparing pMRI to recumbent MRI or other available imaging modalities for diagnosis and management of spinal or CVJ abnormalities were reviewed. All studies of spinal or CVJ imaging in people with EDS were included as well as studies among people with suspected major CVJ or cervical spine abnormalities (cervical or craniovertebral spine instability, basilar invagination, cranial settling, cervical stenosis, spinal cord compression, Chiari

  14. Lumbar disc degeneration was not related to spine and hip bone mineral densities in Chinese: facet joint osteoarthritis may confound the association.

    PubMed

    Pan, Jianjiang; Lu, Xuan; Yang, Ge; Han, Yongmei; Tong, Xiang; Wang, Yue

    2017-12-01

    A sample of 512 Chinese was studied and we observed that greater disc degeneration on MRI was associated with greater spine DXA BMD. Yet, this association may be confounded by facet joint osteoarthritis. BMD may not be a risk factor for lumbar disc degeneration in Chinese. Evidence suggested that lumbar vertebral bone and intervertebral disc interact with each other in multiple ways. The current paper aims to determine the association between bone mineral density (BMD) and lumbar disc degeneration using a sample of Chinese. We studied 165 patients with back disorders and 347 general subjects from China. All subjects had lumbar spine magnetic resonance (MR) imaging and dual- energy X-ray absorptiometry (DXA) spine BMD studies, and a subset of general subjects had additional hip BMD measurements. On T2-weighted MR images, Pfirrmann score was used to evaluate the degree of lumbar disc degeneration and facet joint osteoarthritis was assessed as none, slight-moderate, and severe. Regression analyses were used to examine the associations between lumbar and hip BMD and disc degeneration, adjusting for age, gender, body mass index (BMI), lumbar region, and facet joint osteoarthritis. Greater facet joint osteoarthritis was associated with greater spine BMD (P < 0.01) in both patients and general subjects. For general subjects, greater spine BMD was associated with severe disc degeneration, controlling for age, gender, BMI, and lumbar region. When facet joint osteoarthritis entered the regression model, however, greater spine BMD was associated with greater facet joint osteoarthritis (P < 0.01) but not greater disc degeneration (P > 0.05). No statistical association was observed between spine BMD and lumbar disc degeneration in patients with back disorders (P > 0.05), and between hip BMD and disc degeneration in general subjects (P > 0.05). BMD may not be a risk factor for lumbar disc degeneration in Chinese. Facet joint osteoarthritis inflates DXA spine BMD

  15. Multi-stage 3D-2D registration for correction of anatomical deformation in image-guided spine surgery

    NASA Astrophysics Data System (ADS)

    Ketcha, M. D.; De Silva, T.; Uneri, A.; Jacobson, M. W.; Goerres, J.; Kleinszig, G.; Vogt, S.; Wolinsky, J.-P.; Siewerdsen, J. H.

    2017-06-01

    A multi-stage image-based 3D-2D registration method is presented that maps annotations in a 3D image (e.g. point labels annotating individual vertebrae in preoperative CT) to an intraoperative radiograph in which the patient has undergone non-rigid anatomical deformation due to changes in patient positioning or due to the intervention itself. The proposed method (termed msLevelCheck) extends a previous rigid registration solution (LevelCheck) to provide an accurate mapping of vertebral labels in the presence of spinal deformation. The method employs a multi-stage series of rigid 3D-2D registrations performed on sets of automatically determined and increasingly localized sub-images, with the final stage achieving a rigid mapping for each label to yield a locally rigid yet globally deformable solution. The method was evaluated first in a phantom study in which a CT image of the spine was acquired followed by a series of 7 mobile radiographs with increasing degree of deformation applied. Second, the method was validated using a clinical data set of patients exhibiting strong spinal deformation during thoracolumbar spine surgery. Registration accuracy was assessed using projection distance error (PDE) and failure rate (PDE  >  20 mm—i.e. label registered outside vertebra). The msLevelCheck method was able to register all vertebrae accurately for all cases of deformation in the phantom study, improving the maximum PDE of the rigid method from 22.4 mm to 3.9 mm. The clinical study demonstrated the feasibility of the approach in real patient data by accurately registering all vertebral labels in each case, eliminating all instances of failure encountered in the conventional rigid method. The multi-stage approach demonstrated accurate mapping of vertebral labels in the presence of strong spinal deformation. The msLevelCheck method maintains other advantageous aspects of the original LevelCheck method (e.g. compatibility with standard clinical workflow, large

  16. Longitudinal two-photon imaging in somatosensory cortex of behaving mice reveals dendritic spine formation enhancement by subchronic administration of low-dose ketamine.

    PubMed

    Pryazhnikov, Evgeny; Mugantseva, Ekaterina; Casarotto, Plinio; Kolikova, Julia; Fred, Senem Merve; Toptunov, Dmytro; Afzalov, Ramil; Hotulainen, Pirta; Voikar, Vootele; Terry-Lorenzo, Ryan; Engel, Sharon; Kirov, Sergei; Castren, Eero; Khiroug, Leonard

    2018-04-24

    Ketamine, a well-known anesthetic, has recently attracted renewed attention as a fast-acting antidepressant. A single dose of ketamine induces rapid synaptogenesis, which may underlie its antidepressant effect. To test whether repeated exposure to ketamine triggers sustained synaptogenesis, we administered a sub-anesthetic dose of ketamine (10 mg/kg i.p.) once-daily for 5 days, and repeatedly imaged dendritic spines of the YFP-expressing pyramidal neurons in somatosensory cortex of awake female mice using in vivo two-photon microscopy. We found that the spine formation rate became significantly higher at 72-132 h after the first ketamine injection (but not at 6-24 h), while the rate of elimination of pre-existing spines remained unchanged. In contrast to the net gain of spines observed in ketamine-treated mice, the vehicle-injected control mice exhibited a net loss typical for young-adult animals undergoing synapse pruning. Ketamine-induced spinogenesis was correlated with increased PSD-95 and phosphorylated actin, consistent with formation of new synapses. Moreover, structural synaptic plasticity caused by ketamine was paralleled by a significant improvement in the nest building behavioral assay. Taken together, our data show that subchronic low-dose ketamine induces a sustained shift towards spine formation.

  17. First performance evaluation of software for automatic segmentation, labeling and reformation of anatomical aligned axial images of the thoracolumbar spine at CT.

    PubMed

    Scholtz, Jan-Erik; Wichmann, Julian L; Kaup, Moritz; Fischer, Sebastian; Kerl, J Matthias; Lehnert, Thomas; Vogl, Thomas J; Bauer, Ralf W

    2015-03-01

    To evaluate software for automatic segmentation, labeling and reformation of anatomical aligned axial images of the thoracolumbar spine on CT in terms of accuracy, potential for time savings and workflow improvement. 77 patients (28 women, 49 men, mean age 65.3±14.4 years) with known or suspected spinal disorders (degenerative spine disease n=32; disc herniation n=36; traumatic vertebral fractures n=9) underwent 64-slice MDCT with thin-slab reconstruction. Time for automatic labeling of the thoracolumbar spine and reconstruction of double-angulated axial images of the pathological vertebrae was compared with manually performed reconstruction of anatomical aligned axial images. Reformatted images of both reconstruction methods were assessed by two observers regarding accuracy of symmetric depiction of anatomical structures. In 33 cases double-angulated axial images were created in 1 vertebra, in 28 cases in 2 vertebrae and in 16 cases in 3 vertebrae. Correct automatic labeling was achieved in 72 of 77 patients (93.5%). Errors could be manually corrected in 4 cases. Automatic labeling required 1min in average. In cases where anatomical aligned axial images of 1 vertebra were created, reconstructions made by hand were significantly faster (p<0.05). Automatic reconstruction was time-saving in cases of 2 and more vertebrae (p<0.05). Both reconstruction methods revealed good image quality with excellent inter-observer agreement. The evaluated software for automatic labeling and anatomically aligned, double-angulated axial image reconstruction of the thoracolumbar spine on CT is time-saving when reconstructions of 2 and more vertebrae are performed. Checking results of automatic labeling is necessary to prevent errors in labeling. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  18. Outcomes and Toxicity for Hypofractionated and Single-Fraction Image-Guided Stereotactic Radiosurgery for Sarcomas Metastasizing to the Spine

    SciTech Connect

    Folkert, Michael R.; Bilsky, Mark H.; Tom, Ashlyn K.

    2014-04-01

    Purpose: Conventional radiation treatment (20-40 Gy in 5-20 fractions, 2-5 Gy per fraction) for sarcoma metastatic to the spine provides subtherapeutic doses, resulting in poor durable local control (LC) (50%-77% at 1 year). Hypofractionated (HF) and/or single-fraction (SF) image-guided stereotactic radiosurgery (IG-SRS) may provide a more effective means of managing these lesions. Methods and Materials: Patients with pathologically proven high-grade sarcoma metastatic to the spine treated with HF and SF IG-SRS were included. LC and overall survival (OS) were analyzed by the use of Kaplan-Meier statistics. Univariate and multivariate analyses were performed by the use of Cox regression with competing-risksmore » analysis; all confidence intervals are 95%. Toxicities were assessed according to Common Terminology Criteria for Adverse Events, version 4.0. Results: From May 2005 to November 11, 2012, 88 patients with 120 discrete metastases received HF (3-6 fractions; median dose, 28.5 Gy; n=52, 43.3%) or SF IG-SRS (median dose, 24 Gy; n=68, 56.7%). The median follow-up time was 12.3 months. At 12 months, LC was 87.9% (confidence interval [CI], 81.3%-94.5%), OS was 60.6% (CI, 49.6%-71.6%), and median survival was 16.9 months. SF IG-SRS demonstrated superior LC to HF IG-SRS (12-month LC of 90.8% [CI, 83%-98.6%] vs 84.1% [CI, 72.9%-95.3%] P=.007) and retained significance on multivariate analysis (P=.030, hazard ratio 0.345; CI, 0.132-0.901]. Treatment was well tolerated, with 1% acute grade 3 toxicity, 4.5% chronic grade 3 toxicity, and no grade >3 toxicities. Conclusions: In the largest series of metastatic sarcoma to the spine to date, IG-SRS provides excellent LC in the setting of an aggressive disease with low radiation sensitivity and poor prognosis. Single-fraction IG-SRS is associated with the highest rates of LC with minimal toxicity.« less

  19. Compressed-Sensing Multi-Spectral Imaging of the Post-Operative Spine

    PubMed Central

    Worters, Pauline W.; Sung, Kyunghyun; Stevens, Kathryn J.; Koch, Kevin M.; Hargreaves, Brian A.

    2012-01-01

    Purpose To apply compressed sensing (CS) to in vivo multi-spectral imaging (MSI), which uses additional encoding to avoid MRI artifacts near metal, and demonstrate the feasibility of CS-MSI in post-operative spinal imaging. Materials and Methods Thirteen subjects referred for spinal MRI were examined using T2-weighted MSI. A CS undersampling factor was first determined using a structural similarity index as a metric for image quality. Next, these fully sampled datasets were retrospectively undersampled using a variable-density random sampling scheme and reconstructed using an iterative soft-thresholding method. The fully- and under-sampled images were compared by using a 5-point scale. Prospectively undersampled CS-MSI data were also acquired from two subjects to ensure that the prospective random sampling did not affect the image quality. Results A two-fold outer reduction factor was deemed feasible for the spinal datasets. CS-MSI images were shown to be equivalent or better than the original MSI images in all categories: nerve visualization: p = 0.00018; image artifact: p = 0.00031; image quality: p = 0.0030. No alteration of image quality and T2 contrast was observed from prospectively undersampled CS-MSI. Conclusion This study shows that the inherently sparse nature of MSI data allows modest undersampling followed by CS reconstruction with no loss of diagnostic quality. PMID:22791572

  20. Diagnostic imaging of sacroiliac joints and the spine in the course of spondyloarthropathies

    PubMed Central

    Sudoł-Szopinska, Iwona; Urbanik, Andrzej

    2013-01-01

    Summary Spondyloarthropathies belong to a group of rheumatic diseases, in which inflammatory changes affect mainly the sacroiliac joints, spine, peripheral joints, tendon, ligaments and capsule attachments (entheses). This group includes 6 entities: ankylosing spondylitis, arthritis associated with inflammatory bowel disease, reactive arthritis, undifferentiated spondyloarthropathy, psoriatic arthritis and juvenile spondyloarthropathy. In 2009, ASAS (Assessment in SpondyloArthritis international Society) association, published classification criteria for spondyloarthropathies, which propose standardization of clinical-diagnostic approach in the case of sacroiliitis, spondylitis and arthritis. Radiological diagnosis of inflammatory changes of sacroiliac joints is based on a 4 step radiographic grading method from 1966. According to modified New York criteria, the diagnosis of ankylosing spondylitis is made based on the presence of advanced lesions, sacroiliitis of at least 2 grade bilaterally or 3–4 unilaterally. In case of other types of spondyloarthropathies diagnosis is made based on presence of at least grade 1 changes. In MRI, active inflammation of sacroiliac joints is indicated by the presence of subchondral bone marrow edema, synovitis, bursitis, or enthesitis. ASAS discusses only the classic form of axial spondyloarthropathies, which is ankylosing spondylitis. To quantify radiological inflammatory changes in the course of the disease, Stoke Ankylosing spondylitis classification Spinal Score (SASSS) is recommended. The signs of inflammation and scarrying of the spinal cord in the course of ankylosing spondylitis, present in MRI include: bone marrow edema, sclerosis, fat metaplasia, formation of syndesmophytes, and ankylosis. PMID:23807884

  1. Diffusion-weighted imaging of the spine with a non-carr-purcell-meiboom-gill single-shot fast spin-echo sequence: initial experience.

    PubMed

    Oner, A Y; Tali, T; Celikyay, F; Celik, A; Le Roux, P

    2007-03-01

    To prospectively evaluate the signal-to-noise ratio (SNR) improvement in diffusion-weighted imaging (DWI) of the spine with the use of a newly developed non-Carr-Purcell-Meiboom-Gill (non-CPMG) single-shot fast spin-echo (SS-FSE) sequence and its effect on apparent diffusion coefficient (ADC) measurements. Twenty-four patients were enrolled after written informed consent. DWI of the spine was obtained with an echo-planar imaging (EPI)-based sequence followed by a non-CPMG SS-FSE technique. SNR and ADC values were measured over a lesion-free vertebral corpus. A quality score was assigned for each set of images to assess the image quality. When a spinal lesion was present, contrast-to-noise ratio (CNR) and ADC were also measured. Student t tests were used for statistical analysis. Mean SNR values were 5.83 +/- 2.2 and 11.68 +/- 2.87 for EPI and non-CPMG SS-FSE DWI, respectively. SNR values measured in DWI using parallel imaging were found to be significantly higher (P < .01). Mean ADCs of the spine were 0.53 +/- 0.15 and 0.35 +/- 0.15 x 10(-3) mm(2)/s for EPI and non-CPMG SS-FSE DWI, respectively. Quality scores were found to be higher for the non-CPMG SS-FSE DWI technique (P < .05). Overall lesion CNR was found to be higher in DWI with non-CPMG SS-FSE. The non-CPMG SS-FSE technique provides a significant improvement to current EPI-based DWI of the spine. A study including a larger number of patients is required to determine the use of this DWI sequence as a supplementary tool to conventional MR imaging for increasing diagnostic confidence in spinal pathologic conditions.

  2. Is magnetic resonance imaging in addition to a computed tomographic scan necessary to identify clinically significant cervical spine injuries in obtunded blunt trauma patients?

    PubMed

    Fisher, Brian M; Cowles, Steven; Matulich, Jennifer R; Evanson, Bradley G; Vega, Diana; Dissanaike, Sharmila

    2013-12-01

    Guidelines are in place directing the clearance of the cervical spine in patients who are awake, alert, and oriented, but a gold standard has not been recognized for patients who are obtunded. Our study is designed to determine if magnetic resonance imaging (MRI) detects clinically significant injuries not seen on computed tomographic (CT) scans. The trauma registry was used to identify and retrospectively review medical records of blunt trauma patients from January 1, 2005, to March 30, 2012. Only obtunded patients with a CT scan and MRI of the cervical spine were included. The study cohort consisted of 277 patients. In 13 (5%) patients, MRI detected clinically significant cervical spine injuries that were missed by CT scans, and in 7 (3%) these injuries required intervention. The number needed to screen with MRI to prevent 1 missed injury was 21. The findings suggest that the routine use of MRI in clearing the cervical spine in the obtunded blunt trauma patient. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Chronic 2P-STED imaging reveals high turnover of dendritic spines in the hippocampus in vivo.

    PubMed

    Pfeiffer, Thomas; Poll, Stefanie; Bancelin, Stephane; Angibaud, Julie; Inavalli, Vvg Krishna; Keppler, Kevin; Mittag, Manuel; Fuhrmann, Martin; Nägerl, U Valentin

    2018-06-22

    Rewiring neural circuits by the formation and elimination of synapses is thought to be a key cellular mechanism of learning and memory in the mammalian brain. Dendritic spines are the postsynaptic structural component of excitatory synapses, and their experience-dependent plasticity has been extensively studied in mouse superficial cortex using two-photon microscopy in vivo. By contrast, very little is known about spine plasticity in the hippocampus, which is the archetypical memory center of the brain, mostly because it is difficult to visualize dendritic spines in this deeply embedded structure with sufficient spatial resolution. We developed chronic 2P-STED microscopy in mouse hippocampus, using a 'hippocampal window' based on resection of cortical tissue and a long working distance objective for optical access. We observed a two-fold higher spine density than previous studies and measured a spine turnover of ~40% within 4 days, which depended on spine size. We thus provide direct evidence for a high level of structural rewiring of synaptic circuits and new insights into the structure-dynamics relationship of hippocampal spines. Having established chronic super-resolution microscopy in the hippocampus in vivo, our study enables longitudinal and correlative analyses of nanoscale neuroanatomical structures with genetic, molecular and behavioral experiments. © 2018, Pfeiffer et al.

  4. Real-time ultrasound image classification for spine anesthesia using local directional Hadamard features.

    PubMed

    Pesteie, Mehran; Abolmaesumi, Purang; Ashab, Hussam Al-Deen; Lessoway, Victoria A; Massey, Simon; Gunka, Vit; Rohling, Robert N

    2015-06-01

    Injection therapy is a commonly used solution for back pain management. This procedure typically involves percutaneous insertion of a needle between or around the vertebrae, to deliver anesthetics near nerve bundles. Most frequently, spinal injections are performed either blindly using palpation or under the guidance of fluoroscopy or computed tomography. Recently, due to the drawbacks of the ionizing radiation of such imaging modalities, there has been a growing interest in using ultrasound imaging as an alternative. However, the complex spinal anatomy with different wave-like structures, affected by speckle noise, makes the accurate identification of the appropriate injection plane difficult. The aim of this study was to propose an automated system that can identify the optimal plane for epidural steroid injections and facet joint injections. A multi-scale and multi-directional feature extraction system to provide automated identification of the appropriate plane is proposed. Local Hadamard coefficients are obtained using the sequency-ordered Hadamard transform at multiple scales. Directional features are extracted from local coefficients which correspond to different regions in the ultrasound images. An artificial neural network is trained based on the local directional Hadamard features for classification. The proposed method yields distinctive features for classification which successfully classified 1032 images out of 1090 for epidural steroid injection and 990 images out of 1052 for facet joint injection. In order to validate the proposed method, a leave-one-out cross-validation was performed. The average classification accuracy for leave-one-out validation was 94 % for epidural and 90 % for facet joint targets. Also, the feature extraction time for the proposed method was 20 ms for a native 2D ultrasound image. A real-time machine learning system based on the local directional Hadamard features extracted by the sequency-ordered Hadamard transform for

  5. A software program to measure the three-dimensional length of the spine from radiographic images: Validation and reliability assessment for adolescent idiopathic scoliosis.

    PubMed

    Berger, Steve; Hasler, Carol-Claudius; Grant, Caroline A; Zheng, Guoyan; Schumann, Steffen; Büchler, Philippe

    2017-01-01

    The aim of this study was to validate a new program which aims at measuring the three-dimensional length of the spine's midline based on two calibrated orthogonal radiographic images. The traditional uniplanar T1-S1 measurement method is not reflecting the actual three dimensional curvature of a scoliotic spine and is therefore not accurate. The Spinal Measurement Software (SMS) is an alternative to conveniently measure the true spine's length. The validity, inter- and intra-observer variability and usability of the program were evaluated. The usability was quantified based on a subjective questionnaire filled by eight participants using the program for the first time. The validity and variability were assessed by comparing the length of five phantom spines measured based on CT-scan data and on radiographic images with the SMS. The lengths were measured independently by each participant using both techniques. The SMS is easy and intuitive to use, even for non-clinicians. The SMS measured spinal length with an error below 2 millimeters compared to length obtained using CT scan datasets. The inter- and intra-observer variability of the SMS measurements was below 5 millimeters. The SMS provides accurate measurement of the spinal length based on orthogonal radiographic images. The software is easy to use and could easily integrate the clinical workflow and replace current approximations of the spinal length based on a single radiographic image such as the traditional T1-S1 measurement. Crown Copyright © 2016. Published by Elsevier Ireland Ltd. All rights reserved.

  6. Chance-type flexion-distraction injuries in the thoracolumbar spine: MR imaging characteristics.

    PubMed

    Groves, Clare J; Cassar-Pullicino, Victor N; Tins, Bernhard J; Tyrrell, Prudencia N M; McCall, Iain W

    2005-08-01

    To evaluate retrospectively the magnetic resonance (MR) imaging features of Chance-type flexion-distraction injuries. The authors' institutional review board does not require its approval or patient informed consent for retrospective studies. Imaging data were reviewed retrospectively for 24 patients (15 male, nine female; mean age, 28 years; range, 9-71 years) who had sustained radiographically typical Chance-type flexion-distraction injuries. The posterior vertebral body height remained unchanged or was increased in these patients. Two radiologists recorded a variety of bone and soft-tissue abnormalities seen with MR imaging. Based on consensus, the documented findings were sequentially analyzed to determine their frequencies. Combined bone and soft-tissue injuries occurred in 23 (96%) of 24 patients, were more common than soft-tissue damage alone (one [4%] of 24 patients), and occurred primarily at the thoracolumbar junction. Contiguous vertebral injury was seen in 20 (83%) of 24 patients, usually in the form of anterosuperior vertebral endplate edema, while noncontiguous injury occurred in eight (33%) of 24 patients. Extensive subcutaneous and paraspinal muscle edema was seen in all patients and extended over several segments. Posterior osteoligamentous complex disruption also occurred in all patients. Horizontally oriented fractures of the posterior neural arches produced an MR imaging pattern that the authors call the sandwich sign, which consists of linear hemorrhage framed by marrow edema. This sign was seen in 12 (50%) of 24 patients. In seven (29%) of 24 patients, a fracture line extending from a damaged pedicle was seen to exit through the contralateral posterosuperior aspect of the vertebral body, with extension of the fracture fragments into the spinal canal. A spectrum of features is discernible with MR imaging in Chance-type injuries.

  7. Diagnostic Accuracy of Lumbosacral Spine Magnetic Resonance Image Reading by Chiropractors, Chiropractic Radiologists, and Medical Radiologists.

    PubMed

    de Zoete, Annemarie; Ostelo, Raymond; Knol, Dirk L; Algra, Paul R; Wilmink, Jan T; van Tulder, Maurits W

    2015-06-01

    A cross-sectional diagnostic accuracy study was conducted in 2 sessions. It is important to know whether it is possible to accurately detect "specific findings" on lumbosacral magnetic resonance (MR) images and whether the results of different observers are comparable. Health care providers frequently use magnetic resonance imaging in the diagnostic process of patients with low back pain. The use of MR scans is increasing. This leads to an increase in costs and to an increase in risk of inaccurately labeling patients with an anatomical diagnosis that might not be the actual cause of symptoms. A set of 300 blinded MR images was read by medical radiologists, chiropractors, and chiropractic radiologists in 2 sessions. Each assessor read 100 scans in round 1 and 50 scans in round 2. The reference test was an expert panel.For all analyses, the magnetic resonance imaging findings were dichotomized into "specific findings" or "no specific findings." For the agreement, percentage agreement and κ values were calculated and for validity, sensitivity, and specificity. Sensitivity analysis was done for classifications A and B (prevalence of 31% and 57%, respectively). The intraobserver κ values for chiropractors, chiropractic radiologists, and medical radiologists were 0.46, 0.49, and 0.69 for A and 0.55, 0.75, and 0.64 for B, respectively.The interobserver κ values were lowest for chiropractors (0.28 for A, 0.37 for B) and highest for chiropractic radiologists (0.50 for A, 0.49 for B).The sensitivities of the medical radiologists, chiropractors, and chiropractic radiologists were 0.62, 0.71, and 0.75 for A and 0.70, 0.74, 0.84 for B, respectively.The specificities of medical radiologists, chiropractic radiologists, and chiropractors were 0.82, 0.77, and 0.70 for A and 0.74, 0.52, and 0.61 for B, respectively. Agreement and validity of MR image readings of chiropractors and chiropractic and medical radiologists is modest at best. This study supports recommendations in

  8. Landmark-guided diffeomorphic demons algorithm and its application to automatic segmentation of the whole spine and pelvis in CT images.

    PubMed

    Hanaoka, Shouhei; Masutani, Yoshitaka; Nemoto, Mitsutaka; Nomura, Yukihiro; Miki, Soichiro; Yoshikawa, Takeharu; Hayashi, Naoto; Ohtomo, Kuni; Shimizu, Akinobu

    2017-03-01

    A fully automatic multiatlas-based method for segmentation of the spine and pelvis in a torso CT volume is proposed. A novel landmark-guided diffeomorphic demons algorithm is used to register a given CT image to multiple atlas volumes. This algorithm can utilize both grayscale image information and given landmark coordinate information optimally. The segmentation has four steps. Firstly, 170 bony landmarks are detected in the given volume. Using these landmark positions, an atlas selection procedure is performed to reduce the computational cost of the following registration. Then the chosen atlas volumes are registered to the given CT image. Finally, voxelwise label voting is performed to determine the final segmentation result. The proposed method was evaluated using 50 torso CT datasets as well as the public SpineWeb dataset. As a result, a mean distance error of [Formula: see text] and a mean Dice coefficient of [Formula: see text] were achieved for the whole spine and the pelvic bones, which are competitive with other state-of-the-art methods. From the experimental results, the usefulness of the proposed segmentation method was validated.

  9. [Cervical spine trauma].

    PubMed

    Yilmaz, U; Hellen, P

    2016-08-01

    In the emergency department 65 % of spinal injuries and 2-5 % of blunt force injuries involve the cervical spine. Of these injuries approximately 50 % involve C5 and/or C6 and 30 % involve C2. Older patients tend to have higher spinal injuries and younger patients tend to have lower injuries. The anatomical and development-related characteristics of the pediatric spine as well as degenerative and comorbid pathological changes of the spine in the elderly can make the radiological evaluation of spinal injuries difficult with respect to possible trauma sequelae in young and old patients. Two different North American studies have investigated clinical criteria to rule out cervical spine injuries with sufficient certainty and without using imaging. Imaging of cervical trauma should be performed when injuries cannot be clinically excluded according to evidence-based criteria. Degenerative changes and anatomical differences have to be taken into account in the evaluation of imaging of elderly and pediatric patients.

  10. Lumbar spine disc height and curvature responses to an axial load generated by a compression device compatible with magnetic resonance imaging

    NASA Technical Reports Server (NTRS)

    Kimura, S.; Steinbach, G. C.; Watenpaugh, D. E.; Hargens, A. R.

    2001-01-01

    STUDY DESIGN: Axial load-dependent changes in the lumbar spine of supine healthy volunteers were examined using a compression device compatible with magnetic resonance imaging. OBJECTIVE: To test two hypotheses: Axial loading of 50% body weight from shoulder to feet in supine posture 1) simulates the upright lumbar spine alignment and 2) decreases disc height significantly. SUMMARY OF BACKGROUND DATA: Axial compression on the lumbar spine has significantly narrowed the lumbar dural sac in patients with sciatica, neurogenic claudication or both. METHODS: Using a device compatible with magnetic resonance imaging, the lumbar spine of eight young volunteers, ages 22 to 36 years, was axially compressed with a force equivalent to 50% of body weight, approximating the normal load on the lumbar spine in upright posture. Sagittal lumbar magnetic resonance imaging was performed to measure intervertebral angle and disc height before and during compression. RESULTS: Each intervertebral angle before and during compression was as follows: T12-L1 (-0.8 degrees +/- 2.5 degrees and -1.5 degrees +/- 2.6 degrees ), L1-L2 (0.7 degrees +/- 1.4 degrees and 3.3 degrees +/- 2.9 degrees ), L2-L3 (4.7 degrees +/- 3.5 degrees and 7.3 degrees +/- 6 degrees ), L3-L4 (7.9 degrees +/- 2.4 degrees and 11.1 degrees +/- 4.6 degrees ), L4-L5 (14.3 degrees +/- 3.3 degrees and 14.9 degrees +/- 1.7 degrees ), L5-S1 (25.8 degrees +/- 5.2 degrees and 20.8 degrees +/- 6 degrees ), and L1-S1 (53.4 degrees +/- 11.9 degrees and 57.3 degrees +/- 16.7 degrees ). Negative values reflect kyphosis, and positive values reflect lordosis. A significant difference between values before and during compression was obtained at L3-L4 and L5-S1. There was a significant decrease in disc height only at L4-L5 during compression. CONCLUSIONS: The axial force of 50% body weight in supine posture simulates the upright lumbar spine morphologically. No change in intervertebral angle occurred at L4-L5. However, disc height at L4-L

  11. Effect of Off-Axis Fluoroscopy Imaging on Two-Dimensional Kinematics in the Lumbar Spine: A Dynamic In Vitro Validation Study

    PubMed Central

    Zhao, Kristin D.; Ben-Abraham, Ephraim I.; Magnuson, Dixon J.; Camp, Jon J.; Berglund, Lawrence J.; An, Kai-Nan; Bronfort, Gert; Gay, Ralph E.

    2016-01-01

    Spine intersegmental motion parameters and the resultant regional patterns may be useful for biomechanical classification of low back pain (LBP) as well as assessing the appropriate intervention strategy. Because of its availability and reasonable cost, two-dimensional (2D) fluoroscopy has great potential as a diagnostic and evaluative tool. However, the technique of quantifying intervertebral motion in the lumbar spine must be validated, and the sensitivity assessed. The purpose of this investigation was to (1) compare synchronous fluoroscopic and optoelectronic measures of intervertebral rotations during dynamic flexion–extension movements in vitro and (2) assess the effect of C-arm rotation to simulate off-axis patient alignment on intervertebral kinematics measures. Six cadaveric lumbar–sacrum specimens were dissected, and active marker optoelectronic sensors were rigidly attached to the bodies of L2–S1. Fluoroscopic sequences and optoelectronic kinematic data (0.15-mm linear, 0.17–0.20 deg rotational, accuracy) were obtained simultaneously. After images were obtained in a true sagittal plane, the image receptor was rotated in 5 deg increments (posterior oblique angulations) from 5 deg to 15 deg. Quantitative motion analysis (qma) software was used to determine the intersegmental rotations from the fluoroscopic images. The mean absolute rotation differences between optoelectronic values and dynamic fluoroscopic values were less than 0.5 deg for all the motion segments at each off-axis fluoroscopic rotation and were not significantly different (P > 0.05) for any of the off-axis rotations of the fluoroscope. Small misalignments of the lumbar spine relative to the fluoroscope did not introduce measurement variation in relative segmental rotations greater than that observed when the spine and fluoroscope were perpendicular to each other, suggesting that fluoroscopic measures of relative segmental rotation during flexion–extension are likely

  12. Effect of Off-Axis Fluoroscopy Imaging on Two-Dimensional Kinematics in the Lumbar Spine: A Dynamic In Vitro Validation Study.

    PubMed

    Zhao, Kristin D; Ben-Abraham, Ephraim I; Magnuson, Dixon J; Camp, Jon J; Berglund, Lawrence J; An, Kai-Nan; Bronfort, Gert; Gay, Ralph E

    2016-05-01

    Spine intersegmental motion parameters and the resultant regional patterns may be useful for biomechanical classification of low back pain (LBP) as well as assessing the appropriate intervention strategy. Because of its availability and reasonable cost, two-dimensional (2D) fluoroscopy has great potential as a diagnostic and evaluative tool. However, the technique of quantifying intervertebral motion in the lumbar spine must be validated, and the sensitivity assessed. The purpose of this investigation was to (1) compare synchronous fluoroscopic and optoelectronic measures of intervertebral rotations during dynamic flexion-extension movements in vitro and (2) assess the effect of C-arm rotation to simulate off-axis patient alignment on intervertebral kinematics measures. Six cadaveric lumbar-sacrum specimens were dissected, and active marker optoelectronic sensors were rigidly attached to the bodies of L2-S1. Fluoroscopic sequences and optoelectronic kinematic data (0.15-mm linear, 0.17-0.20 deg rotational, accuracy) were obtained simultaneously. After images were obtained in a true sagittal plane, the image receptor was rotated in 5 deg increments (posterior oblique angulations) from 5 deg to 15 deg. Quantitative motion analysis (qma) software was used to determine the intersegmental rotations from the fluoroscopic images. The mean absolute rotation differences between optoelectronic values and dynamic fluoroscopic values were less than 0.5 deg for all the motion segments at each off-axis fluoroscopic rotation and were not significantly different (P > 0.05) for any of the off-axis rotations of the fluoroscope. Small misalignments of the lumbar spine relative to the fluoroscope did not introduce measurement variation in relative segmental rotations greater than that observed when the spine and fluoroscope were perpendicular to each other, suggesting that fluoroscopic measures of relative segmental rotation during flexion-extension are likely robust, even when

  13. Computed Tomography (CT) - Spine

    MedlinePlus

    ... Resources Professions Site Index A-Z Computed Tomography (CT) - Spine Computed tomography (CT) of the spine is ... of CT Scanning of the Spine? What is CT Scanning of the Spine? Computed tomography, more commonly ...

  14. Cumulative effective dose and cancer risk for pediatric population in repetitive full spine follow-up imaging: How micro dose is the EOS microdose protocol?

    PubMed

    Law, Martin; Ma, Wang-Kei; Lau, Damian; Cheung, Kenneth; Ip, Janice; Yip, Lawrance; Lam, Wendy

    2018-04-01

    To evaluate and to obtain analytic formulation for the calculation of the effective dose and associated cancer risk using the EOS microdose protocol for scoliotic pediatric patients undergoing full spine imaging at different age of exposure; to demonstrate the microdose protocol capable of delivering lesser radiation dose and hence of further reducing cancer risk induction when compared with the EOS low dose protocol; to obtain cumulative effective dose and cancer risk for both genders scoliotic pediatrics of US and Hong Kong population using the microdose protocol. Organ absorbed doses of full spine exposed scoliotic pediatric patients have been simulated with the use of EOS microdose protocol imaging parameters input to the Monte Carlo software PCXMC. Gender and age specific effective dose has been calculated with the simulated organ absorbed dose using the ICRP-103 approach. The associated radiation induced cancer risk, expressed as lifetime attributable risk (LAR), has been estimated according to the method introduced in the Biological Effects of Ionizing Radiation VII report. Values of LAR have been estimated for scoliotic patients exposed repetitively during their follow up period at different age for US and Hong Kong population. The effective doses of full spine imaging with simultaneous posteroanterior and lateral projection for patients exposed at the age between 5 and 18 years using the EOS microdose protocol have been calculated within the range of 2.54-14.75 μSv. The corresponding LAR for US and Hong Kong population was ranged between 0.04 × 10 -6 and 0.84 × 10 -6 . Cumulative effective dose and cancer risk during follow-up period can be estimated using the results and are of information to patients and their parents. With the use of computer simulation and analytic formulation, we obtained the cumulative effective dose and cancer risk at any age of exposure for pediatric patients of US and Hong Kong population undergoing repetitive

  15. Fast inner-volume imaging of the lumbar spine with a spatially focused excitation using a 3D-TSE sequence.

    PubMed

    Riffel, Philipp; Michaely, Henrik J; Morelli, John N; Paul, Dominik; Kannengiesser, Stephan; Schoenberg, Stefan O; Haneder, Stefan

    2015-04-01

    The purpose of this study was to evaluate the feasibility and technical quality of a zoomed three-dimensional (3D) turbo spin-echo (TSE) sampling perfection with application optimized contrasts using different flip-angle evolutions (SPACE) sequence of the lumbar spine. In this prospective feasibility study, nine volunteers underwent a 3-T magnetic resonance examination of the lumbar spine including 1) a conventional 3D T2-weighted (T2w) SPACE sequence with generalized autocalibrating partially parallel acquisition technique acceleration factor 2 and 2) a zoomed 3D T2w SPACE sequence with a reduced field of view (reduction factor 2). Images were evaluated with regard to image sharpness, signal homogeneity, and the presence of artifacts by two experienced radiologists. For quantitative analysis, signal-to-noise ratio (SNR) values were calculated. Image sharpness of anatomic structures was statistically significantly greater with zoomed SPACE (P < .0001), whereas the signal homogeneity was statistically significantly greater with conventional SPACE (cSPACE; P = .0003). There were no statistically significant differences in extent of artifacts. Acquisition times were 8:20 minutes for cSPACE and 6:30 minutes for zoomed SPACE. Readers 1 and 2 selected zSPACE as the preferred sequence in five of nine cases. In two of nine cases, both sequences were rated as equally preferred by both the readers. SNR values were statistically significantly greater with cSPACE. In comparison to a cSPACE sequences, zoomed SPACE imaging of the lumbar spine provides sharper images in conjunction with a 25% reduction in acquisition time. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.

  16. The use of adaptive statistical iterative reconstruction (ASiR) technique in evaluation of patients with cervical spine trauma: impact on radiation dose reduction and image quality

    PubMed Central

    Sheikh, Adnan

    2016-01-01

    Objective: The aim of this study was to evaluate the impact of adaptive statistical iterative reconstruction (ASiR) technique on the image quality and radiation dose reduction. The comparison was made with the traditional filtered back projection (FBP) technique. Methods: We retrospectively reviewed 78 patients, who underwent cervical spine CT for blunt cervical trauma between 1 June 2010 and 30 November 2010. 48 patients were imaged using traditional FBP technique and the remaining 30 patients were imaged using the ASiR technique. The patient demographics, radiation dose, objective image signal and noise were recorded; while subjective noise, sharpness, diagnostic acceptability and artefacts were graded by two radiologists blinded to the techniques. Results: We found that the ASiR technique was able to reduce the volume CT dose index, dose–length product and effective dose by 36%, 36.5% and 36.5%, respectively, compared with the FBP technique. There was no significant difference in the image noise (p = 0.39), signal (p = 0.82) and signal-to-noise ratio (p = 0.56) between the groups. The subjective image quality was minimally better in the ASiR group but not statistically significant. There was excellent interobserver agreement on the subjective image quality and diagnostic acceptability for both groups. Conclusion: The use of ASiR technique allowed approximately 36% radiation dose reduction in the evaluation of cervical spine without degrading the image quality. Advances in knowledge: The present study highlights that the ASiR technique is extremely helpful in reducing the patient radiation exposure while maintaining the image quality. It is highly recommended to utilize this novel technique in CT imaging of different body regions. PMID:26882825

  17. The use of adaptive statistical iterative reconstruction (ASiR) technique in evaluation of patients with cervical spine trauma: impact on radiation dose reduction and image quality.

    PubMed

    Patro, Satya N; Chakraborty, Santanu; Sheikh, Adnan

    2016-01-01

    The aim of this study was to evaluate the impact of adaptive statistical iterative reconstruction (ASiR) technique on the image quality and radiation dose reduction. The comparison was made with the traditional filtered back projection (FBP) technique. We retrospectively reviewed 78 patients, who underwent cervical spine CT for blunt cervical trauma between 1 June 2010 and 30 November 2010. 48 patients were imaged using traditional FBP technique and the remaining 30 patients were imaged using the ASiR technique. The patient demographics, radiation dose, objective image signal and noise were recorded; while subjective noise, sharpness, diagnostic acceptability and artefacts were graded by two radiologists blinded to the techniques. We found that the ASiR technique was able to reduce the volume CT dose index, dose-length product and effective dose by 36%, 36.5% and 36.5%, respectively, compared with the FBP technique. There was no significant difference in the image noise (p = 0.39), signal (p = 0.82) and signal-to-noise ratio (p = 0.56) between the groups. The subjective image quality was minimally better in the ASiR group but not statistically significant. There was excellent interobserver agreement on the subjective image quality and diagnostic acceptability for both groups. The use of ASiR technique allowed approximately 36% radiation dose reduction in the evaluation of cervical spine without degrading the image quality. The present study highlights that the ASiR technique is extremely helpful in reducing the patient radiation exposure while maintaining the image quality. It is highly recommended to utilize this novel technique in CT imaging of different body regions.

  18. SU-E-J-34: Setup Accuracy in Spine SBRT Using CBCT 6D Image Guidance in Comparison with 6D ExacTrac

    SciTech Connect

    Han, Z; Yip, S; Lewis, J

    2015-06-15

    Purpose Volumetric information of the spine captured on CBCT can potentially improve the accuracy in spine SBRT setup that has been commonly performed through 2D radiographs. This work evaluates the setup accuracy in spine SBRT using 6D CBCT image guidance that recently became available on Varian systems. Methods ExacTrac radiographs have been commonly used for Spine SBRT setup. The setup process involves first positioning patients with lasers followed by localization imaging, registration, and repositioning. Verification images are then taken providing the residual errors (ExacTracRE) before beam on. CBCT verification is also acquired in our institute. The availability of both ExacTracmore » and CBCT verifications allows a comparison study. 41 verification CBCT of 16 patients were retrospectively registered with the planning CT enabling 6D corrections, giving CBCT residual errors (CBCTRE) which were compared with ExacTracRE. Results The RMS discrepancies between CBCTRE and ExacTracRE are 1.70mm, 1.66mm, 1.56mm in vertical, longitudinal and lateral directions and 0.27°, 0.49°, 0.35° in yaw, roll and pitch respectively. The corresponding mean discrepancies (and standard deviation) are 0.62mm (1.60mm), 0.00mm (1.68mm), −0.80mm (1.36mm) and 0.05° (0.58°), 0.11° (0.48°), −0.16° (0.32°). Of the 41 CBCT, 17 had high-Z surgical implants. No significant difference in ExacTrac-to-CBCT discrepancy was observed between patients with and without the implants. Conclusion Multiple factors can contribute to the discrepancies between CBCT and ExacTrac: 1) the imaging iso-centers of the two systems, while calibrated to coincide, can be different; 2) the ROI used for registration can be different especially if ribs were included in ExacTrac images; 3) small patient motion can occur between the two verification image acquisitions; 4) the algorithms can be different between CBCT (volumetric) and ExacTrac (radiographic) registrations.« less

  19. SU-E-I-51: Use of Blade Sequences in Cervical Spine MR Imaging for Eliminating Motion, Truncation and Flow Artifacts

    SciTech Connect

    Mavroidis, P; Lavdas, E; Kostopoulos, S

    Purpose: To assess the efficacy of the BLADE technique to eliminate motion, truncation, flow and other artifacts in Cervical Spine MRI compared to the conventional technique. To study the ability of the examined sequences to reduce the indetention and wrap artifacts, which have been reported in BLADE sagittal sequences. Methods: Forty consecutive subjects, who had been routinely scanned for cervical spine examination using four different image acquisition techniques, were analyzed. More specifically, the following pairs of sequences were compared: a) T2 TSE SAG vs. T2 TSE SAG BLADE and b) T2 TIRM SAG vs. T2 TIRM SAG BLADE. A quantitativemore » analysis was performed using the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and relative contrast (ReCon) measures. A qualitative analysis was also performed by two radiologists, who graded seven image characteristics on a 5-point scale (0:non-visualization; 1:poor; 2:average; 3:good; 4:excellent). The observers also evaluated the presence of image artifacts (motion, truncation, flow, indentation). Results: Based on the findings of the quantitative analysis, the ReCON values of the CSF (cerebrospinal fluid)/SC (spinal cord) between TIRM SAG and TIRM SAG BLADE were found to present statistical significant differences (p<0.001). Regarding motion and truncation artifacts, the T2 TSE SAG BLADE was superior compared to the T2 TSE SAG and the T2 TIRM SAG BLADE was superior compared to the T2 TIRM SAG. Regarding flow artifacts, T2 TIRM SAG BLADE eliminated more artifacts compared to the T2 TIRM SAG. Conclusion: The use of BLADE sequences in cervical spine MR examinations appears to be capable of potentially eliminating motion, pulsatile flow and trancation artifacts. Furthermore, BLADE sequences are proposed to be used in the standard examination protocols based on the fact that a significantly improved image quality could be achieved.« less

  20. Body mass index and waist circumference in early adulthood are associated with thoracolumbar spine shape at age 60-64: The Medical Research Council National Survey of Health and Development.

    PubMed

    Pavlova, Anastasia V; Muthuri, Stella G; Cooper, Rachel; Saunders, Fiona R; Gregory, Jennifer S; Barr, Rebecca J; Martin, Kathryn R; Adams, Judith E; Kuh, Diana; Hardy, Rebecca J; Aspden, Richard M

    2018-01-01

    This study investigated associations between measures of adiposity from age 36 and spine shape at 60-64 years. Thoracolumbar spine shape was characterised using statistical shape modelling on lateral dual-energy x-ray absorptiometry images of the spine from 1529 participants of the MRC National Survey of Health and Development, acquired at age 60-64. Associations of spine shape modes with: 1) contemporaneous measures of total and central adiposity (body mass index (BMI), waist circumference (WC)) and body composition (android:gynoid fat mass ratio and lean and fat mass indices, calculated as whole body (excluding the head) lean or fat mass (kg) divided by height2 (m)2); 2) changes in total and central adiposity between age 36 and 60-64 and 3) age at onset of overweight, were tested using linear regression models. Four modes described 79% of the total variance in spine shape. In men, greater lean mass index was associated with a larger lordosis whereas greater fat mass index was associated with straighter spines. Greater current BMI was associated with a more uneven curvature in men and with larger anterior-posterior (a-p) vertebral diameters in both sexes. Greater WC and fat mass index were also associated with a-p diameter in both sexes. There was no clear evidence that gains in BMI and WC during earlier stages of adulthood were associated with spine shape but younger onset of overweight was associated with a more uneven spine and greater a-p diameter. In conclusion, sagittal spine shapes had different associations with total and central adiposity; earlier onset of overweight and prior measures of WC were particularly important.

  1. Observer agreement in the reporting of knee and lumbar spine magnetic resonance (MR) imaging examinations: selectively trained MR radiographers and consultant radiologists compared with an index radiologist.

    PubMed

    Brealey, S; Piper, K; King, D; Bland, M; Caddick, J; Campbell, P; Gibbon, A; Highland, A; Jenkins, N; Petty, D; Warren, D

    2013-10-01

    To assess agreement between trained radiographers and consultant radiologists compared with an index radiologist when reporting on magnetic resonance imaging (MRI) examinations of the knee and lumbar spine and to examine the subsequent effect of discordant reports on patient management and outcome. At York Hospital two MR radiographers, two consultant radiologists and an index radiologist reported on a prospective, random sample of 326 MRI examinations. The radiographers reported in clinical practice conditions and the radiologists during clinical practice. An independent consultant radiologist compared these reports with the index radiologist report for agreement. Orthopaedic surgeons then assessed whether the discordance between reports was clinically important. Overall observer agreement with the index radiologist was comparable between observers and ranged from 54% to 58%; for the knee it was 46-57% and for the lumbar spine was 56-66%. There was a very small observed difference of 0.6% (95% CI -11.9 to 13.0) in mean agreement between the radiographers and radiologists (P=0.860). For the knee, lumbar spine and overall, radiographers' discordant reports, when compared with the index radiologist, were less likely to have a clinically important effect on patient outcome than the radiologists' discordant reports. Less than 10% of observer's reports were sufficiently discordant with the index radiologist's reports to be clinically important. Carefully selected MR radiographers with postgraduate education and training reported in clinical practice conditions on specific MRI examinations of the knee and lumbar spine to a level of agreement comparable with non-musculoskeletal consultant radiologists. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. The degenerative cervical spine.

    PubMed

    Llopis, E; Belloch, E; León, J P; Higueras, V; Piquer, J

    2016-04-01

    Imaging techniques provide excellent anatomical images of the cervical spine. The choice to use one technique or another will depend on the clinical scenario and on the treatment options. Plain-film X-rays continue to be fundamental, because they make it possible to evaluate the alignment and bone changes; they are also useful for follow-up after treatment. The better contrast resolution provided by magnetic resonance imaging makes it possible to evaluate the soft tissues, including the intervertebral discs, ligaments, bone marrow, and spinal cord. The role of computed tomography in the study of degenerative disease has changed in recent years owing to its great spatial resolution and its capacity to depict osseous components. In this article, we will review the anatomy and biomechanical characteristics of the cervical spine, and then we provide a more detailed discussion of the degenerative diseases that can affect the cervical spine and their clinical management. Copyright © 2015 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

  3. Changes in Primary Care Health Care Utilization after Inclusion of Epidemiologic Data in Lumbar Spine MR Imaging Reports for Uncomplicated Low Back Pain.

    PubMed

    Fried, Jessica G; Andrew, Angeline S; Ring, Natalie Y; Pastel, David A

    2018-05-01

    Purpose To determine whether inclusion of an epidemiologic statement in radiology reports of lumbar magnetic resonance (MR) imaging influences downstream health care utilization in the primary care population. Materials and Methods Beginning July 1, 2013, a validated epidemiologic statement regarding prevalence of common findings in asymptomatic patients was included in all lumbar MR imaging reports at a tertiary academic medical center. Data were collected from July 1, 2012, through June 30, 2014, and retrospective analysis was completed in September 2016. The electronic medical record was reviewed to capture health care utilization rates in patients for 1 year after index MR imaging. Of 4527 eligible adult patients with low back pain referred for lumbar spine MR imaging during the study period, 375 patients had their studies ordered by in-network primary care providers, did not have findings other than degenerative disease, and had at least one follow-up encounter within the system within 1 year of index MR imaging. In the before-and-after study design, a pre-statement-implementation cohort was compared with a post-statement-implementation cohort by using univariate and multivariate statistical models to evaluate treatment utilization rates in these groups. Results Patients in the statement group were 12% less likely to be referred to a spine specialist (137 of 187 [73%] vs 159 of 188 [85%]; P = .007) and were 7% less likely to undergo repeat imaging (seven of 187 [4%] vs 20 of 188 [11%]; P = .01) compared with patients in the nonstatement group. The intervention was not associated with any change in narcotic prescription (53 of 188 [28%] vs 54 of 187 [29%]; P = .88) or with the rate of low back surgery (24 of 188 [13%] vs 16 of 187 [9%]; P = .19). Conclusion In this study, inclusion of a simple epidemiologic statement in lumbar MR imaging reports was associated with decreased utilization in high-cost domains of low back pain management. © RSNA, 2018.

  4. Diagnostic Approach to Pediatric Spine Disorders.

    PubMed

    Rossi, Andrea; Martinetti, Carola; Morana, Giovanni; Severino, Mariasavina; Tortora, Domenico

    2016-08-01

    Understanding the developmental features of the pediatric spine and spinal cord, including embryologic steps and subsequent growth of the osteocartilaginous spine and contents is necessary for interpretation of the pathologic events that may affect the pediatric spine. MR imaging plays a crucial role in the diagnostic evaluation of patients suspected of harboring spinal abnormalities, whereas computed tomography and ultrasonography play a more limited, complementary role. This article discusses the embryologic and developmental anatomy features of the spine and spinal cord, together with some technical points and pitfalls, and the most common indications for pediatric spinal MR imaging. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Peripheral nervous system injury after high-dose single-fraction image-guided stereotactic radiosurgery for spine tumors.

    PubMed

    Stubblefield, Michael D; Ibanez, Katarzyna; Riedel, Elyn R; Barzilai, Ori; Laufer, Ilya; Lis, Eric; Yamada, Yoshiya; Bilsky, Mark H

    2017-03-01

    OBJECTIVE The object of this study was to determine the percentage of high-dose (1800-2600 cGy) single-fraction stereotactic radiosurgery (SF-SRS) treatments to the spine that result in peripheral nervous system (PNS) injury. METHODS All patients treated with SF-SRS for primary or metastatic spine tumors between January 2004 and May 2013 and referred to the Rehabilitation Medicine Service for evaluation and treatment of neuromuscular, musculoskeletal, or functional impairments or pain were retrospectively identified. RESULTS Five hundred fifty-seven SF-SRS treatments in 447 patients resulted in 14 PNS injuries in 13 patients. All injures resulted from SF-SRS delivered to the cervical or lumbosacral spine at 2400 cGy. The overall percentage of SF-SRS treatments resulting in PNS injury was 2.5%, increasing to 4.5% when the thoracic spine was excluded from analysis. The median time to symptom onset following SF-SRS was 10 months (range 4-32 months). The plexus (cervical, brachial, and/or lumbosacral) was affected clinically and/or electrophysiologically in 12 (86%) of 14 cases, the nerve root in 2 (14%) of 14, and both in 6 (43%) of 14 cases. All patients experienced pain and most (93%) developed weakness. Peripheral nervous system injuries were CTCAE Grade 1 in 14% of cases, 2 in 64%, and 3 in 21%. No dose relationship between SF-SRS dose and PNS injury was detected. CONCLUSIONS Single-fraction SRS to the spine can result in PNS injury with major implications for function and quality of life.

  6. WE-AB-BRA-01: 3D-2D Image Registration for Target Localization in Spine Surgery: Comparison of Similarity Metrics Against Robustness to Content Mismatch

    SciTech Connect

    De Silva, T; Ketcha, M; Siewerdsen, J H

    Purpose: In image-guided spine surgery, mapping 3D preoperative images to 2D intraoperative images via 3D-2D registration can provide valuable assistance in target localization. However, the presence of surgical instrumentation, hardware implants, and soft-tissue resection/displacement causes mismatches in image content, confounding existing registration methods. Manual/semi-automatic methods to mask such extraneous content is time consuming, user-dependent, error prone, and disruptive to clinical workflow. We developed and evaluated 2 novel similarity metrics within a robust registration framework to overcome such challenges in target localization. Methods: An IRB-approved retrospective study in 19 spine surgery patients included 19 preoperative 3D CT images and 50 intraoperativemore » mobile radiographs in cervical, thoracic, and lumbar spine regions. A neuroradiologist provided truth definition of vertebral positions in CT and radiography. 3D-2D registration was performed using the CMA-ES optimizer with 4 gradient-based image similarity metrics: (1) gradient information (GI); (2) gradient correlation (GC); (3) a novel variant referred to as gradient orientation (GO); and (4) a second variant referred to as truncated gradient correlation (TGC). Registration accuracy was evaluated in terms of the projection distance error (PDE) of the vertebral levels. Results: Conventional similarity metrics were susceptible to gross registration error and failure modes associated with the presence of surgical instrumentation: for GI, the median PDE and interquartile range was 33.0±43.6 mm; similarly for GC, PDE = 23.0±92.6 mm respectively. The robust metrics GO and TGC, on the other hand, demonstrated major improvement in PDE (7.6 ±9.4 mm and 8.1± 18.1 mm, respectively) and elimination of gross failure modes. Conclusion: The proposed GO and TGC similarity measures improve registration accuracy and robustness to gross failure in the presence of strong image content mismatch

  7. The spine neck filters membrane potentials.

    PubMed

    Araya, Roberto; Jiang, Jiang; Eisenthal, Kenneth B; Yuste, Rafael

    2006-11-21

    Dendritic spines receive most synaptic inputs in the forebrain. Their morphology, with a spine head isolated from the dendrite by a slender neck, indicates a potential role in isolating inputs. Indeed, biochemical compartmentalization occurs at spine heads because of the diffusional bottleneck created by the spine neck. Here we investigate whether the spine neck also isolates inputs electrically. Using two-photon uncaging of glutamate on spine heads from mouse layer-5 neocortical pyramidal cells, we find that the amplitude of uncaging potentials at the soma is inversely proportional to neck length. This effect is strong and independent of the position of the spine in the dendritic tree and size of the spine head. Moreover, spines with long necks are electrically silent at the soma, although their heads are activated by the uncaging event, as determined with calcium imaging. Finally, second harmonic measurements of membrane potential reveal an attenuation of somatic voltages into the spine head, an attenuation directly proportional to neck length. We conclude that the spine neck plays an electrical role in the transmission of membrane potentials, isolating synapses electrically.

  8. The spine neck filters membrane potentials

    PubMed Central

    Araya, Roberto; Jiang, Jiang; Eisenthal, Kenneth B.; Yuste, Rafael

    2006-01-01

    Dendritic spines receive most synaptic inputs in the forebrain. Their morphology, with a spine head isolated from the dendrite by a slender neck, indicates a potential role in isolating inputs. Indeed, biochemical compartmentalization occurs at spine heads because of the diffusional bottleneck created by the spine neck. Here we investigate whether the spine neck also isolates inputs electrically. Using two-photon uncaging of glutamate on spine heads from mouse layer-5 neocortical pyramidal cells, we find that the amplitude of uncaging potentials at the soma is inversely proportional to neck length. This effect is strong and independent of the position of the spine in the dendritic tree and size of the spine head. Moreover, spines with long necks are electrically silent at the soma, although their heads are activated by the uncaging event, as determined with calcium imaging. Finally, second harmonic measurements of membrane potential reveal an attenuation of somatic voltages into the spine head, an attenuation directly proportional to neck length. We conclude that the spine neck plays an electrical role in the transmission of membrane potentials, isolating synapses electrically. PMID:17093040

  9. Osteoradionecrosis of the upper cervical spine after radiation therapy for head and neck cancer: differentiation from recurrent or metastatic disease with MR imaging.

    PubMed

    Wu, Li-An; Liu, Hon-Man; Wang, Chun-Wei; Chen, Ya-Fang; Hong, Ruey-Long; Ko, Jenq-Yuh

    2012-07-01

    To compare the magnetic resonance (MR) imaging features of upper cervical spine osteoradionecrosis (ORN) with those of recurrent or metastatic disease after the treatment of head and neck malignancies. This retrospective study was approved by the hospital institutional review board, and the requirement to obtain informed consent was waived. From January 2005 to December 2010, 35 patients who had undergone irradiation of head and neck cancer and who had subsequent C1 or C2 lesions at MR imaging were enrolled. Pathology reports, clinical records, and follow-up MR images were reviewed to classify patients into one of two groups-those with ORN or those with recurrence. The MR imaging characteristics in these patients were evaluated. Statistical significance of intergroup differences was assessed by means of the Pearson χ2 or Fisher exact test for categorical variables and the two-sample t test for continuous variables. ORN was diagnosed in 20 of the 35 patients (57%), and recurrent or metastatic disease was diagnosed in 15 (43%). Ten of the 35 patients (29%) had undergone biopsy of the cervical spine or paraspinal soft tissue. The MR images in the ORN group showed significantly more contiguous involvement of the atlantoaxial or atlanto-occipital bones with intervening joint change (P<.001), more cases of vertebral body collapse (P<.01), more bilateral symmetric involvement of the vertebral body (P<.01), and continuation of vertebral body changes with posterior pharyngeal wall ulceration (P<.01). Posterior arch or other cervical level involvement, paraspinal solid mass, epidural involvement, lateral border cortical destruction, and cervical lymphadenopathy were noted more frequently in the recurrence group than in the ORN group (P=.03, P<.001, P=.02, P<.001, and P<.01, respectively). Various MR imaging characteristics can be used to help differentiate between cervical ORN and recurrent disease. © RSNA, 2012.

  10. Radiation dose reduction in thoracic and lumbar spine instrumentation using navigation based on an intraoperative cone beam CT imaging system: a prospective randomized clinical trial.

    PubMed

    Pireau, Nathalie; Cordemans, Virginie; Banse, Xavier; Irda, Nadia; Lichtherte, Sébastien; Kaminski, Ludovic

    2017-11-01

    Spine surgery still remains a challenge for every spine surgeon, aware of the potential serious outcomes of misplaced instrumentation. Though many studies have highlighted that using intraoperative cone beam CT imaging and navigation systems provides higher accuracy than conventional freehand methods for placement of pedicle screws in spine surgery, few studies are concerned about how to reduce radiation exposure for patients with the use of such technology. One of the main focuses of this study is based on the ALARA principle (as low as reasonably achievable). A prospective randomized trial was conducted in the hybrid operating room between December 2015 and December 2016, including 50 patients operated on for posterior instrumented thoracic and/or lumbar spinal fusion. Patients were randomized to intraoperative 3D acquisition high-dose (standard dose) or low-dose protocol, and a total of 216 pedicle screws were analyzed in terms of screw position. Two different methods were used to measure ionizing radiation: the total skin dose (derived from the dose-area product) and the radiation dose evaluated by thermoluminescent dosimeters on the surgical field. According to Gertzbein and Heary classifications, low-dose protocol provided a significant higher accuracy of pedicle screw placement than the high-dose protocol (96.1 versus 92%, respectively). Seven screws (3.2%), all implanted with the high-dose protocol, needed to be revised intraoperatively. The use of low-dose acquisition protocols reduced patient exposure by a factor of five. This study emphasizes the paramount importance of using low-dose protocols for intraoperative cone beam CT imaging coupled with the navigation system, as it at least does not affect the accuracy of pedicle screw placement and irradiates drastically less.

  11. Spine Trabecular Bone Score as an Indicator of Bone Microarchitecture at the Peripheral Skeleton in Kidney Transplant Recipients.

    PubMed

    Luckman, Matthew; Hans, Didier; Cortez, Natalia; Nishiyama, Kyle K; Agarawal, Sanchita; Zhang, Chengchen; Nikkel, Lucas; Iyer, Sapna; Fusaro, Maria; Guo, Edward X; McMahon, Donald J; Shane, Elizabeth; Nickolas, Thomas L

    2017-04-03

    Studies using high-resolution peripheral quantitative computed tomography showed progressive abnormalities in cortical and trabecular microarchitecture and biomechanical competence over the first year after kidney transplantation. However, high-resolution peripheral computed tomography is a research tool lacking wide availability. In contrast, the trabecular bone score is a novel and widely available tool that uses gray-scale variograms of the spine image from dual-energy x-ray absorptiometry to assess trabecular quality. There are no studies assessing whether trabecular bone score characterizes bone quality in kidney transplant recipients. Between 2009 and 2010, we conducted a study to assess changes in peripheral skeletal microarchitecture, measured by high-resolution peripheral computed tomography, during the first year after transplantation in 47 patients managed with early corticosteroid-withdrawal immunosuppression. All adult first-time transplant candidates were eligible. Patients underwent imaging with high-resolution peripheral computed tomography and dual-energy x-ray absorptiometry pretransplantation and 3, 6, and 12 months post-transplantation. We now test if, during the first year after transplantation, trabecular bone score assesses the evolution of bone microarchitecture and biomechanical competence as determined by high-resolution peripheral computed tomography. At baseline and follow-up, among the 72% and 78%, respectively, of patients having normal bone mineral density by dual-energy x-ray absorptiometry, 53% and 50%, respectively, were classified by trabecular bone score as having high fracture risk. At baseline, trabecular bone score correlated with spine, hip, and ultradistal radius bone mineral density by dual-energy x-ray absorptiometry and cortical area, density, thickness, and porosity; trabecular density, thickness, separation, and heterogeneity; and stiffness and failure load by high-resolution peripheral computed tomography

  12. Spine Trabecular Bone Score as an Indicator of Bone Microarchitecture at the Peripheral Skeleton in Kidney Transplant Recipients

    PubMed Central

    Luckman, Matthew; Hans, Didier; Cortez, Natalia; Nishiyama, Kyle K.; Agarawal, Sanchita; Zhang, Chengchen; Nikkel, Lucas; Iyer, Sapna; Fusaro, Maria; Guo, Edward X.; McMahon, Donald J.; Shane, Elizabeth

    2017-01-01

    Background and objectives Studies using high-resolution peripheral quantitative computed tomography showed progressive abnormalities in cortical and trabecular microarchitecture and biomechanical competence over the first year after kidney transplantation. However, high-resolution peripheral computed tomography is a research tool lacking wide availability. In contrast, the trabecular bone score is a novel and widely available tool that uses gray-scale variograms of the spine image from dual-energy x-ray absorptiometry to assess trabecular quality. There are no studies assessing whether trabecular bone score characterizes bone quality in kidney transplant recipients. Design, settings, participants, & measurements Between 2009 and 2010, we conducted a study to assess changes in peripheral skeletal microarchitecture, measured by high-resolution peripheral computed tomography, during the first year after transplantation in 47 patients managed with early corticosteroid–withdrawal immunosuppression. All adult first-time transplant candidates were eligible. Patients underwent imaging with high-resolution peripheral computed tomography and dual-energy x-ray absorptiometry pretransplantation and 3, 6, and 12 months post-transplantation. We now test if, during the first year after transplantation, trabecular bone score assesses the evolution of bone microarchitecture and biomechanical competence as determined by high-resolution peripheral computed tomography. Results At baseline and follow-up, among the 72% and 78%, respectively, of patients having normal bone mineral density by dual-energy x-ray absorptiometry, 53% and 50%, respectively, were classified by trabecular bone score as having high fracture risk. At baseline, trabecular bone score correlated with spine, hip, and ultradistal radius bone mineral density by dual-energy x-ray absorptiometry and cortical area, density, thickness, and porosity; trabecular density, thickness, separation, and heterogeneity; and

  13. Lumbar spine CT scan

    MedlinePlus

    CAT scan - lumbar spine; Computed axial tomography scan - lumbar spine; Computed tomography scan - lumbar spine; CT - lower back ... CT scans rapidly makes detailed pictures of the lower back. The test may be used to look for: ...

  14. Cervical spine CT scan

    MedlinePlus

    ... cervical spine; Computed tomography scan of cervical spine; CT scan of cervical spine; Neck CT scan ... table that slides into the center of the CT scanner. Once you are inside the scanner, the ...

  15. Techniques for deriving tissue structure from multiple projection dual-energy x-ray absorptiometry

    NASA Technical Reports Server (NTRS)

    Feldmesser, Howard S. (Inventor); Charles, Jr., Harry K. (Inventor); Beck, Thomas J. (Inventor); Magee, Thomas C. (Inventor)

    2004-01-01

    Techniques for deriving bone properties from images generated by a dual-energy x-ray absorptiometry apparatus include receiving first image data having pixels indicating bone mineral density projected at a first angle of a plurality of projection angles. Second image data and third image data are also received. The second image data indicates bone mineral density projected at a different second angle. The third image data indicates bone mineral density projected at a third angle. The third angle is different from the first angle and the second angle. Principal moments of inertia for a bone in the subject are computed based on the first image data, the second image data and the third image data. The techniques allow high-precision, high-resolution dual-energy x-ray attenuation images to be used for computing principal moments of inertia and strength moduli of individual bones, plus risk of injury and changes in risk of injury to a patient.

  16. Investigation of suspected Guillain-Barre syndrome in childhood: what is the role for gadolinium enhanced magnetic resonance imaging of the spine?

    PubMed

    Smith, Nicholas; Pereira, John; Grattan-Smith, Padraic

    2014-10-01

    To review the role of gadolinium-enhanced magnetic resonance imaging of the spine in the diagnosis of paediatric Guillain-Barre syndrome and compare it with nerve conduction studies and cerebrospinal fluid analysis. A retrospective review of investigations undertaken in children admitted to our institution with acute Guillain-Barre syndrome over a 10-year period was performed. Seven of eight children (88%) displayed post-gadolinium nerve root enhancement consistent with Guillain-Barre syndrome. This compared with supportive nerve conduction studies in 21/24 children (88%) and cerebrospinal fluid protein analysis consistent with the diagnosis in 16/20 children (80%). Nerve conduction studies are the recognised 'gold standard' technique for confirming a clinical diagnosis of Guillain-Barre syndrome. In this study, a high positive rate was demonstrated. While more experience is necessary, this study and the literature support gadolinium enhanced magnetic resonance imaging of the spine as a valuable, although not necessarily superior, investigation in the diagnosis of Guillain-Barre syndrome. It may be of particular benefit when specialist neurophysiology expertise is unavailable. © 2010 The Authors. Journal compilation © 2010 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

  17. Dose, image quality and spine modeling assessment of biplanar EOS micro-dose radiographs for the follow-up of in-brace adolescent idiopathic scoliosis patients.

    PubMed

    Morel, Baptiste; Moueddeb, Sonia; Blondiaux, Eleonore; Richard, Stephen; Bachy, Manon; Vialle, Raphael; Ducou Le Pointe, Hubert

    2018-05-01

    The aim of this study was to compare the radiation dose, image quality and 3D spine parameter measurements of EOS low-dose and micro-dose protocols for in-brace adolescent idiopathic scoliosis (AIS) patients. We prospectively included 25 consecutive patients (20 females, 5 males) followed for AIS and undergoing brace treatment. The mean age was 12 years (SD 2 years, range 8-15 years). For each patient, in-brace biplanar EOS radiographs were acquired in a standing position using both the conventional low-dose and micro-dose protocols. Dose area product (DAP) was systematically recorded. Diagnostic image quality was qualitatively assessed by two radiologists for visibility of anatomical structures. The reliability of 3D spine modeling between two operators was quantitatively evaluated for the most clinically relevant 3D radiological parameters using intraclass correlation coefficient (ICC). The mean DAP for the posteroanterior and lateral acquisitions was 300 ± 134 and 433 ± 181 mGy cm 2 for the low-dose radiographs, and 41 ± 19 and 81 ± 39 mGy cm 2 for micro-dose radiographs. Image quality was lower with the micro-dose protocol. The agreement was "good" to "very good" for all measured clinical parameters when comparing the low-dose and micro-dose protocols (ICC > 0.73). The micro-dose protocol substantially reduced the delivered dose (by a factor of 5-7 compared to the low-dose protocol) in braced children with AIS. Although image quality was reduced, the micro-dose protocol proved to be adapted to radiological follow-up, with adequate image quality and reliable clinical measurements. These slides can be retrieved under Electronic Supplementary Material.

  18. Comparison of Natural Language Processing Rules-based and Machine-learning Systems to Identify Lumbar Spine Imaging Findings Related to Low Back Pain.

    PubMed

    Tan, W Katherine; Hassanpour, Saeed; Heagerty, Patrick J; Rundell, Sean D; Suri, Pradeep; Huhdanpaa, Hannu T; James, Kathryn; Carrell, David S; Langlotz, Curtis P; Organ, Nancy L; Meier, Eric N; Sherman, Karen J; Kallmes, David F; Luetmer, Patrick H; Griffith, Brent; Nerenz, David R; Jarvik, Jeffrey G

    2018-03-28

    To evaluate a natural language processing (NLP) system built with open-source tools for identification of lumbar spine imaging findings related to low back pain on magnetic resonance and x-ray radiology reports from four health systems. We used a limited data set (de-identified except for dates) sampled from lumbar spine imaging reports of a prospectively assembled cohort of adults. From N = 178,333 reports, we randomly selected N = 871 to form a reference-standard dataset, consisting of N = 413 x-ray reports and N = 458 MR reports. Using standardized criteria, four spine experts annotated the presence of 26 findings, where 71 reports were annotated by all four experts and 800 were each annotated by two experts. We calculated inter-rater agreement and finding prevalence from annotated data. We randomly split the annotated data into development (80%) and testing (20%) sets. We developed an NLP system from both rule-based and machine-learned models. We validated the system using accuracy metrics such as sensitivity, specificity, and area under the receiver operating characteristic curve (AUC). The multirater annotated dataset achieved inter-rater agreement of Cohen's kappa > 0.60 (substantial agreement) for 25 of 26 findings, with finding prevalence ranging from 3% to 89%. In the testing sample, rule-based and machine-learned predictions both had comparable average specificity (0.97 and 0.95, respectively). The machine-learned approach had a higher average sensitivity (0.94, compared to 0.83 for rules-based), and a higher overall AUC (0.98, compared to 0.90 for rules-based). Our NLP system performed well in identifying the 26 lumbar spine findings, as benchmarked by reference-standard annotation by medical experts. Machine-learned models provided substantial gains in model sensitivity with slight loss of specificity, and overall higher AUC. Copyright © 2018 The Association of University Radiologists. All rights reserved.

  19. Improved fat-suppression homogeneity with mDIXON turbo spin echo (TSE) in pediatric spine imaging at 3.0 T.

    PubMed

    Pokorney, Amber L; Chia, Jonathan M; Pfeifer, Cory M; Miller, Jeffrey H; Hu, Houchun H

    2017-11-01

    Background Robust fat suppression remains essential in clinical MRI to improve tissue signal contrast, minimize fat-related artifacts, and enhance image quality. Purpose To compare fat suppression between mDIXON turbo spin echo (TSE) and conventional frequency-selective and inversion-recovery methods in pediatric spine MRI. Material and Methods Images from T1-weighted (T1W) and T2-weighted (T2W) TSE sequences coupled with conventional methods and the mDIXON technique were compared in 36 patients (5.8 ± 5.4 years) at 3.0 T. Images from 42 pairs of T1W (n = 16) and T2W (n = 26) scans were acquired. Two radiologists reviewed the data and rated images using a three-point scale in two categories, including the uniformity of fat suppression and overall diagnostic image quality. The Wilcoxon rank-sum test was used to compare the scores. Results The Cohen's kappa coefficient for inter-rater agreement was 0.69 (95% confidence interval [CI], 0.56-0.83). Images from mDIXON TSE were considered superior in fat suppression ( P < 0.01) in 22 (rater 1) and 25 (rater 2) cases, respectively. In 13 (rater 1) and 11 (rater 2) cases, mDIXON TSE demonstrated improved diagnostic image quality ( P < 0.01). In three cases, fat suppression was superior using inversion-recovery and likewise in one case mDIXON had poorer image diagnostic quality. Lastly, mDIXON and conventional fat-suppression methods performed similarly in 17 (rater 1) and 14 (rater 2) cases, and yielded equal diagnostic image quality in 28 (rater 1) and 30 (rater 2) cases. Conclusion Robust fat suppression can be achieved with mDixon TSE pediatric spine imaging at 3.0 T and should be considered as a permanent replacement of traditional methods, in particular frequency-selective techniques.

  20. Prevalence of degenerative and spondyloarthritis-related magnetic resonance imaging findings in the spine and sacroiliac joints in patients with persistent low back pain.

    PubMed

    Arnbak, Bodil; Jensen, Tue S; Egund, Niels; Zejden, Anna; Hørslev-Petersen, Kim; Manniche, Claus; Jurik, Anne G

    2016-04-01

    To estimate the prevalence of degenerative and spondyloarthritis (SpA)-related magnetic resonance imaging (MRI) findings in the spine and sacroiliac joints (SIJs) and analyse their association with gender and age in persistent low back pain (LBP) patients. Degenerative and SpA-related MRI findings in the whole spine and SIJs were evaluated in Spine Centre patients aged 18-40 years with LBP. Among the 1,037 patients, the prevalence of disc degeneration, disc contour changes and vertebral endplate signal (Modic) changes were 87 % (±SEM 1.1), 82 % (±1.2) and 48 % (±1.6). All degenerative spinal findings were most frequent in men and patients aged 30-40 years. Spinal SpA-related MRI findings were rare. In the SIJs, 28 % (±1.4) had at least one MRI finding, with bone marrow oedema being the most common (21 % (±1.3)). SIJ erosions were most prevalent in patients aged 18-29 years and bone marrow oedema in patients aged 30-40 years. SIJ sclerosis and fatty marrow deposition were most common in women. SIJ bone marrow oedema, sclerosis and erosions were most frequent in women indicating pregnancy-related LBP. The high prevalence of SIJ MRI findings associated with age, gender, and pregnancy-related LBP need further investigation of their clinical importance in LBP patients. • The location of vertebral endplate signal changes supports a mechanical aetiology. • Several sacroiliac joint findings were associated with female gender and pregnancy-related back pain. • Sacroiliac joint bone marrow oedema was frequent and age-associated, indicating a possible degenerative aetiology. • More knowledge of the clinical importance of sacroiliac joint MRI findings is needed.

  1. Three-dimensional kinematic stress magnetic resonance image analysis shows promise for detecting altered anatomical relationships of tissues in the cervical spine associated with painful radiculopathy.

    PubMed

    Jaumard, N V; Udupa, J K; Siegler, S; Schuster, J M; Hilibrand, A S; Hirsch, B E; Borthakur, A; Winkelstein, B A

    2013-10-01

    For some patients with radiculopathy a source of nerve root compression cannot be identified despite positive electromyography (EMG) evidence. This discrepancy hampers the effective clinical management for these individuals. Although it has been well-established that tissues in the cervical spine move in a three-dimensional (3D) manner, the 3D motions of the neural elements and their relationship to the bones surrounding them are largely unknown even for asymptomatic normal subjects. We hypothesize that abnormal mechanical loading of cervical nerve roots during pain-provoking head positioning may be responsible for radicular pain in those cases in which there is no evidence of nerve root compression on conventional cervical magnetic resonance imaging (MRI) with the neck in the neutral position. This biomechanical imaging proof-of-concept study focused on quantitatively defining the architectural relationships between the neural and bony structures in the cervical spine using measurements derived from 3D MR images acquired in neutral and pain-provoking neck positions for subjects: (1) with radicular symptoms and evidence of root compression by conventional MRI and positive EMG, (2) with radicular symptoms and no evidence of root compression by MRI but positive EMG, and (3) asymptomatic age-matched controls. Function and pain scores were measured, along with neck range of motion, for all subjects. MR imaging was performed in both a neutral position and a pain-provoking position. Anatomical architectural data derived from analysis of the 3D MR images were compared between symptomatic and asymptomatic groups, and the symptomatic groups with and without imaging evidence of root compression. Several differences in the architectural relationships between the bone and neural tissues were identified between the asymptomatic and symptomatic groups. In addition, changes in architectural relationships were also detected between the symptomatic groups with and without imaging

  2. Cervical Spine MRI in Abused Infants.

    ERIC Educational Resources Information Center

    Feldman, Kenneth W.; And Others

    1997-01-01

    This study attempted to use cervical spine magnetic resonance imaging (MRI) to detect cord injury in 12 dead children with head injury from child abuse. Eighty percent of children autopsied had small cervical spine hemorrhages; MRI did not identify them and did not identify cord injury in any child studied, indicating that MRI scans are probably…

  3. Vertebral fractures assessed with dual-energy X-ray absorptiometry in patients with Addison's disease on glucocorticoid and mineralocorticoid replacement therapy.

    PubMed

    Camozzi, Valentina; Betterle, Corrado; Frigo, Anna Chiara; Zaccariotto, Veronica; Zaninotto, Martina; De Caneva, Erica; Lucato, Paola; Gomiero, Walter; Garelli, Silvia; Sabbadin, Chiara; Salvà, Monica; Costa, Miriam Dalla; Boscaro, Marco; Luisetto, Giovanni

    2018-02-01

    to assess bone damage and metabolic abnormalities in patients with Addison's disease given replacement doses of glucocorticoids and mineralocorticoids. A total of 87 patients and 81 age-matched and sex-matched healthy controls were studied. The following parameters were measured: urinary cortisol, serum calcium, phosphorus, creatinine, 24-h urinary calcium excretion, bone alkaline phosphatase, parathyroid hormone, serum CrossLaps, 25 hydroxyvitamin D, and 1,25 dihydroxyvitamin D. Clear vertebral images were obtained with dual-energy X-ray absorptiometry in 61 Addison's disease patients and 47 controls and assessed using Genant's classification. Nineteen Addison's disease patients (31.1%) had at least one morphometric vertebral fracture, as opposed to six controls (12.8%, odds ratio 3.09, 95% confidence interval 1.12-8.52). There were no significant differences in bone mineral density parameters at any site between patients and controls. In Addison's disease patients, there was a positive correlation between urinary cortisol and urinary calcium excretion. Patients with fractures had a longer history of disease than those without fractures. Patients taking fludrocortisone had a higher bone mineral density than untreated patients at all sites except the lumbar spine. Addison's disease patients have more fragile bones irrespective of any decrease in bone mineral density. Supra-physiological doses of glucocorticoids and longer-standing disease (with a consequently higher glucocorticoid intake) might be the main causes behind patients' increased bone fragility. Associated mineralocorticoid treatment seems to have a protective effect on bone mineral density.

  4. Effectiveness of a Rapid Lumbar Spine MRI Protocol Using 3D T2-Weighted SPACE Imaging Versus a Standard Protocol for Evaluation of Degenerative Changes of the Lumbar Spine.

    PubMed

    Sayah, Anousheh; Jay, Ann K; Toaff, Jacob S; Makariou, Erini V; Berkowitz, Frank

    2016-09-01

    Reducing lumbar spine MRI scanning time while retaining diagnostic accuracy can benefit patients and reduce health care costs. This study compares the effectiveness of a rapid lumbar MRI protocol using 3D T2-weighted sampling perfection with application-optimized contrast with different flip-angle evolutions (SPACE) sequences with a standard MRI protocol for evaluation of lumbar spondylosis. Two hundred fifty consecutive unenhanced lumbar MRI examinations performed at 1.5 T were retrospectively reviewed. Full, rapid, and complete versions of each examination were interpreted for spondylotic changes at each lumbar level, including herniations and neural compromise. The full examination consisted of sagittal T1-weighted, T2-weighted turbo spin-echo (TSE), and STIR sequences; and axial T1- and T2-weighted TSE sequences (time, 18 minutes 40 seconds). The rapid examination consisted of sagittal T1- and T2-weighted SPACE sequences, with axial SPACE reformations (time, 8 minutes 46 seconds). The complete examination consisted of the full examination plus the T2-weighted SPACE sequence. Sensitivities and specificities of the full and rapid examinations were calculated using the complete study as the reference standard. The rapid and full studies had sensitivities of 76.0% and 69.3%, with specificities of 97.2% and 97.9%, respectively, for all degenerative processes. Rapid and full sensitivities were 68.7% and 66.3% for disk herniation, 85.2% and 81.5% for canal compromise, 82.9% and 69.1% for lateral recess compromise, and 76.9% and 69.7% for foraminal compromise, respectively. Isotropic SPACE T2-weighted imaging provides high-quality imaging of lumbar spondylosis, with multiplanar reformatting capability. Our SPACE-based rapid protocol had sensitivities and specificities for herniations and neural compromise comparable to those of the protocol without SPACE. This protocol fits within a 15-minute slot, potentially reducing costs and discomfort for a large subgroup of

  5. Relationship between MRI-measured bone marrow adipose tissue and hip and spine bone mineral density in African-American and Caucasian participants: the CARDIA study.

    PubMed

    Shen, Wei; Scherzer, Rebecca; Gantz, Madeleine; Chen, Jun; Punyanitya, Mark; Lewis, Cora E; Grunfeld, Carl

    2012-04-01

    An increasing number of studies suggest that bone marrow adipose tissue (BMAT) might play a role in the pathogenesis of osteoporosis. Our previous study of Caucasian women demonstrated that there is an inverse relationship between BMAT and whole-body bone mineral density (BMD). It is unknown whether visceral adipose tissue (VAT), sc adipose tissue (SAT), and skeletal muscle had an effect on the relationship between BMAT and BMD. In the present study we investigated the relationship between pelvic, hip, and lumbar spine BMAT with hip and lumbar spine BMD in the population-based Coronary Artery Risk Development in Young Adults (CARDIA) sample with adjustment for whole-body magnetic resonance imaging (MRI)-measured VAT, SAT, and skeletal muscle. T1-weighted MRI was acquired for 210 healthy African-American and Caucasian men and women (age 38-52 yr). Hip and lumbar spine BMD were measured by dual-energy x-ray absorptiometry. Pelvic, hip, and lumbar spine BMAT had negative correlations with hip and lumbar spine BMD (r = -0.399 to -0.550, P < 0.001). The inverse associations between BMAT and BMD remained strong after adjusting for demographics, weight, skeletal muscle, SAT, VAT, total adipose tissue (TAT), menopausal status, lifestyle factors, and inflammatory markers (standardized regression coefficients = -0. 296 to -0.549, P < 0.001). Among body composition measures, skeletal muscle was the strongest correlate of BMD after adjusting for BMAT (standardized regression coefficients = 0.268-0.614, P < 0.05), with little additional contribution from weight, SAT, VAT, or total adipose tissue. In this middle-aged population, a negative relationship existed between MRI-measured BMAT and hip and lumbar spine BMD independent of demographics and body composition. These observations support the growing evidence linking BMAT with low bone density.

  6. Relationship between MRI-Measured Bone Marrow Adipose Tissue and Hip and Spine Bone Mineral Density in African-American and Caucasian Participants: The CARDIA Study

    PubMed Central

    Scherzer, Rebecca; Gantz, Madeleine; Chen, Jun; Punyanitya, Mark; Lewis, Cora E.; Grunfeld, Carl

    2012-01-01

    Context: An increasing number of studies suggest that bone marrow adipose tissue (BMAT) might play a role in the pathogenesis of osteoporosis. Our previous study of Caucasian women demonstrated that there is an inverse relationship between BMAT and whole-body bone mineral density (BMD). It is unknown whether visceral adipose tissue (VAT), sc adipose tissue (SAT), and skeletal muscle had an effect on the relationship between BMAT and BMD. Objective: In the present study we investigated the relationship between pelvic, hip, and lumbar spine BMAT with hip and lumbar spine BMD in the population-based Coronary Artery Risk Development in Young Adults (CARDIA) sample with adjustment for whole-body magnetic resonance imaging (MRI)-measured VAT, SAT, and skeletal muscle. Design: T1-weighted MRI was acquired for 210 healthy African-American and Caucasian men and women (age 38–52 yr). Hip and lumbar spine BMD were measured by dual-energy x-ray absorptiometry. Results: Pelvic, hip, and lumbar spine BMAT had negative correlations with hip and lumbar spine BMD (r = −0.399 to −0.550, P < 0.001). The inverse associations between BMAT and BMD remained strong after adjusting for demographics, weight, skeletal muscle, SAT, VAT, total adipose tissue (TAT), menopausal status, lifestyle factors, and inflammatory markers (standardized regression coefficients = −0. 296 to −0.549, P < 0.001). Among body composition measures, skeletal muscle was the strongest correlate of BMD after adjusting for BMAT (standardized regression coefficients = 0.268–0.614, P < 0.05), with little additional contribution from weight, SAT, VAT, or total adipose tissue. Conclusion: In this middle-aged population, a negative relationship existed between MRI-measured BMAT and hip and lumbar spine BMD independent of demographics and body composition. These observations support the growing evidence linking BMAT with low bone density. PMID:22319043

  7. Spine stereotactic body radiotherapy utilizing cone-beam CT image-guidance with a robotic couch: intrafraction motion analysis accounting for all six degrees of freedom.

    PubMed

    Hyde, Derek; Lochray, Fiona; Korol, Renee; Davidson, Melanie; Wong, C Shun; Ma, Lijun; Sahgal, Arjun

    2012-03-01

    To evaluate the residual setup error and intrafraction motion following kilovoltage cone-beam CT (CBCT) image guidance, for immobilized spine stereotactic body radiotherapy (SBRT) patients, with positioning corrected for in all six degrees of freedom. Analysis is based on 42 consecutive patients (48 thoracic and/or lumbar metastases) treated with a total of 106 fractions and 307 image registrations. Following initial setup, a CBCT was acquired for patient alignment and a pretreatment CBCT taken to verify shifts and determine the residual setup error, followed by a midtreatment and posttreatment CBCT image. For 13 single-fraction SBRT patients, two midtreatment CBCT images were obtained. Initially, a 1.5-mm and 1° tolerance was used to reposition the patient following couch shifts which was subsequently reduced to 1 mm and 1° degree after the first 10 patients. Small positioning errors after the initial CBCT setup were observed, with 90% occurring within 1 mm and 97% within 1°. In analyzing the impact of the time interval for verification imaging (10 ± 3 min) and subsequent image acquisitions (17 ± 4 min), the residual setup error was not significantly different (p > 0.05). A significant difference (p = 0.04) in the average three-dimensional intrafraction positional deviations favoring a more strict tolerance in translation (1 mm vs. 1.5 mm) was observed. The absolute intrafraction motion averaged over all patients and all directions along x, y, and z axis (± SD) were 0.7 ± 0.5 mm and 0.5 ± 0.4 mm for the 1.5 mm and 1 mm tolerance, respectively. Based on a 1-mm and 1° correction threshold, the target was localized to within 1.2 mm and 0.9° with 95% confidence. Near-rigid body immobilization, intrafraction CBCT imaging approximately every 15-20 min, and strict repositioning thresholds in six degrees of freedom yields minimal intrafraction motion allowing for safe spine SBRT delivery. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Reduction of artifacts caused by orthopedic hardware in the spine in spectral detector CT examinations using virtual monoenergetic image reconstructions and metal-artifact-reduction algorithms.

    PubMed

    Große Hokamp, Nils; Neuhaus, V; Abdullayev, N; Laukamp, K; Lennartz, S; Mpotsaris, A; Borggrefe, J

    2018-02-01

    Aim of this study was to assess the artifact reduction in patients with orthopedic hardware in the spine as provided by (1) metal-artifact-reduction algorithms (O-MAR) and (2) virtual monoenergetic images (MonoE) as provided by spectral detector CT (SDCT) compared to conventional iterative reconstruction (CI). In all, 28 consecutive patients with orthopedic hardware in the spine who underwent SDCT-examinations were included. CI, O-MAR and MonoE (40-200 keV) images were reconstructed. Attenuation (HU) and noise (SD) were measured in order to calculate signal-to-noise ratio (SNR) of paravertebral muscle and spinal canal. Subjective image quality was assessed by two radiologists in terms of image quality and extent of artifact reduction. O-MAR and high-keV MonoE showed significant decrease of hypodense artifacts in terms of higher attenuation as compared to CI (CI vs O-MAR, 200 keV MonoE: -396.5HU vs. -115.2HU, -48.1HU; both p ≤ 0.001). Further, artifacts as depicted by noise were reduced in O-MAR and high-keV MonoE as compared to CI in (1) paravertebral muscle and (2) spinal canal-CI vs. O-MAR/200 keV: (1) 34.7 ± 19.0 HU vs. 26.4 ± 14.4 HU, p ≤ 0.05/27.4 ± 16.1, n.s.; (2) 103.4 ± 61.3 HU vs. 72.6 ± 62.6 HU/60.9 ± 40.1 HU, both p ≤ 0.001. Subjectively both O-MAR and high-keV images yielded an artifact reduction in up to 24/28 patients. Both, O-MAR and high-keV MonoE reconstructions as provided by SDCT lead to objective and subjective artifact reduction, thus the combination of O-MAR and MonoE seems promising for further reduction.

  9. Cervical Spine Instrumentation in Children.

    PubMed

    Hedequist, Daniel J; Emans, John B

    2016-06-01

    Instrumentation of the cervical spine enhances stability and improves arthrodesis rates in children undergoing surgery for deformity or instability. Various morphologic and clinical studies have been conducted in children, confirming the feasibility of anterior or posterior instrumentation of the cervical spine with modern implants. Knowledge of the relevant spine anatomy and preoperative imaging studies can aid the clinician in understanding the pitfalls of instrumentation for each patient. Preoperative planning, intraoperative positioning, and adherence to strict surgical techniques are required given the small size of children. Instrumentation options include anterior plating, occipital plating, and a variety of posterior screw techniques. Complications related to screw malposition include injury to the vertebral artery, neurologic injury, and instrumentation failure.

  10. Posteroanterior versus anteroposterior lumbar spine radiology

    SciTech Connect

    Tsuno, M.M.; Shu, G.J.

    The posteroanterior view of the lumbar spine has important features including radiation protection and image quality; these have been studied by various investigators. Investigators have shown that sensitive tissues receive less radiation dosage in the posteroanterior view of the spine for scoliosis screening and intracranial tomography without altering the image quality. This paper emphasizes the importance of the radiation safety aspect of the posteroanterior view and shows the improvement in shape distortion in the lumbar vertebrae.

  11. Multilevel magnetic resonance imaging analysis of multifidus-longissimus cleavage planes in the lumbar spine and potential clinical applications to Wiltse's paraspinal approach.

    PubMed

    Palmer, Daniel Kyle; Allen, Jonathan L; Williams, Paul A; Voss, Ashley Elizabeth; Jadhav, Vikram; Wu, David S; Cheng, Wayne K

    2011-07-15

    Retrospective magnetic resonance imaging (MRI)-based study. Our goal was to develop Wiltse's paraspinal surgical approach by determining the precise anatomic locations of the intermuscular cleavage planes formed by the multifidus and longissimus muscles. The primary objective was to measure the distances between the midline and the intermuscular planes, bilaterally, on MRI scans at each of the five disc levels between L1 and S1. Secondary objectives included identifying the existence of any correlations between patient demographics and the measured outcomes. In 1968, Wiltse described an approach to the spine using the natural cleavage plane of the multifidus and longissimus muscles as an entry to the posterior spinal elements. The small direct incisions lessened bleeding, tissue violation, and muscle retraction, which popularized Wiltse's approach among surgeons. A detailed description of the locations of the intermuscular cleavage planes at each lumbar disc level, however, is not available. MRI scans of 200 patients taken during routine care (2007-2009) were retrospectively reviewed to gather measurements of the distances from the intermuscular cleavage planes to the midline, bilaterally, at each disc level from L1 to S1. Age, sex, and BMI (body mass index) were obtained to determine correlations. Mean measurements significantly differed between all disc levels. At L5-S1, the mean distance was 37.8 mm; at L4-L5, 28.4 mm; at L3-L4, 16.2 mm; at L2-L3, 10.4 mm; and at L1-L2, 7.9 mm. The mean female distances were significantly greater than males (2 mm) on both sides of L5-S1 only. No correlation was discovered between BMI, age, height (N = 50), or weight (N = 50) with respect to measured distances. In the absence of any significant clinical correlation between patient demographics and the entry site in Wiltse's approach, the spine surgeon may use distances described in this paper to apply to a broad base of spine patients regardless of BMI, sex, or age.

  12. Identifying factors likely to influence compliance with diagnostic imaging guideline recommendations for spine disorders among chiropractors in North America: a focus group study using the Theoretical Domains Framework

    PubMed Central

    2012-01-01

    Background The Theoretical Domains Framework (TDF) was developed to investigate determinants of specific clinical behaviors and inform the design of interventions to change professional behavior. This framework was used to explore the beliefs of chiropractors in an American Provider Network and two Canadian provinces about their adherence to evidence-based recommendations for spine radiography for uncomplicated back pain. The primary objective of the study was to identify chiropractors’ beliefs about managing uncomplicated back pain without x-rays and to explore barriers and facilitators to implementing evidence-based recommendations on lumbar spine x-rays. A secondary objective was to compare chiropractors in the United States and Canada on their beliefs regarding the use of spine x-rays. Methods Six focus groups exploring beliefs about managing back pain without x-rays were conducted with a purposive sample. The interview guide was based upon the TDF. Focus groups were digitally recorded, transcribed verbatim, and analyzed by two independent assessors using thematic content analysis based on the TDF. Results Five domains were identified as likely relevant. Key beliefs within these domains included the following: conflicting comments about the potential consequences of not ordering x-rays (risk of missing a pathology, avoiding adverse treatment effects, risks of litigation, determining the treatment plan, and using x-ray-driven techniques contrasted with perceived benefits of minimizing patient radiation exposure and reducing costs; beliefs about consequences); beliefs regarding professional autonomy, professional credibility, lack of standardization, and agreement with guidelines widely varied ( social/professional role & identity); the influence of formal training, colleagues, and patients also appeared to be important factors ( social influences); conflicting comments regarding levels of confidence and comfort in managing patients without x-rays ( belief

  13. Identifying factors likely to influence compliance with diagnostic imaging guideline recommendations for spine disorders among chiropractors in North America: a focus group study using the Theoretical Domains Framework.

    PubMed

    Bussières, André E; Patey, Andrea M; Francis, Jill J; Sales, Anne E; Grimshaw, Jeremy M; Brouwers, Melissa; Godin, Gaston; Hux, Jan; Johnston, Marie; Lemyre, Louise; Pomey, Marie-Pascale; Sales, Anne; Zwarenstein, Merrick

    2012-08-31

    The Theoretical Domains Framework (TDF) was developed to investigate determinants of specific clinical behaviors and inform the design of interventions to change professional behavior. This framework was used to explore the beliefs of chiropractors in an American Provider Network and two Canadian provinces about their adherence to evidence-based recommendations for spine radiography for uncomplicated back pain. The primary objective of the study was to identify chiropractors' beliefs about managing uncomplicated back pain without x-rays and to explore barriers and facilitators to implementing evidence-based recommendations on lumbar spine x-rays. A secondary objective was to compare chiropractors in the United States and Canada on their beliefs regarding the use of spine x-rays. Six focus groups exploring beliefs about managing back pain without x-rays were conducted with a purposive sample. The interview guide was based upon the TDF. Focus groups were digitally recorded, transcribed verbatim, and analyzed by two independent assessors using thematic content analysis based on the TDF. Five domains were identified as likely relevant. Key beliefs within these domains included the following: conflicting comments about the potential consequences of not ordering x-rays (risk of missing a pathology, avoiding adverse treatment effects, risks of litigation, determining the treatment plan, and using x-ray-driven techniques contrasted with perceived benefits of minimizing patient radiation exposure and reducing costs; beliefs about consequences); beliefs regarding professional autonomy, professional credibility, lack of standardization, and agreement with guidelines widely varied ( social/professional role & identity); the influence of formal training, colleagues, and patients also appeared to be important factors ( social influences); conflicting comments regarding levels of confidence and comfort in managing patients without x-rays ( belief about capabilities); and

  14. Mobile C-arm cone-beam CT for guidance of spine surgery: Image quality, radiation dose, and integration with interventional guidance

    SciTech Connect

    Schafer, S.; Nithiananthan, S.; Mirota, D. J.

    Purpose: A flat-panel detector based mobile isocentric C-arm for cone-beam CT (CBCT) has been developed to allow intraoperative 3D imaging with sub-millimeter spatial resolution and soft-tissue visibility. Image quality and radiation dose were evaluated in spinal surgery, commonly relying on lower-performance image intensifier based mobile C-arms. Scan protocols were developed for task-specific imaging at minimum dose, in-room exposure was evaluated, and integration of the imaging system with a surgical guidance system was demonstrated in preclinical studies of minimally invasive spine surgery. Methods: Radiation dose was assessed as a function of kilovolt (peak) (80-120 kVp) and milliampere second using thoracic andmore » lumbar spine dosimetry phantoms. In-room radiation exposure was measured throughout the operating room for various CBCT scan protocols. Image quality was assessed using tissue-equivalent inserts in chest and abdomen phantoms to evaluate bone and soft-tissue contrast-to-noise ratio as a function of dose, and task-specific protocols (i.e., visualization of bone or soft-tissues) were defined. Results were applied in preclinical studies using a cadaveric torso simulating minimally invasive, transpedicular surgery. Results: Task-specific CBCT protocols identified include: thoracic bone visualization (100 kVp; 60 mAs; 1.8 mGy); lumbar bone visualization (100 kVp; 130 mAs; 3.2 mGy); thoracic soft-tissue visualization (100 kVp; 230 mAs; 4.3 mGy); and lumbar soft-tissue visualization (120 kVp; 460 mAs; 10.6 mGy) - each at (0.3 x 0.3 x 0.9 mm{sup 3}) voxel size. Alternative lower-dose, lower-resolution soft-tissue visualization protocols were identified (100 kVp; 230 mAs; 5.1 mGy) for the lumbar region at (0.3 x 0.3 x 1.5 mm{sup 3}) voxel size. Half-scan orbit of the C-arm (x-ray tube traversing under the table) was dosimetrically advantageous (prepatient attenuation) with a nonuniform dose distribution ({approx}2 x higher at the entrance side than at

  15. Clinical safety of the ProMRI pacemaker system in patients subjected to thoracic spine and cardiac 1.5-T magnetic resonance imaging scanning conditions.

    PubMed

    Bailey, William M; Mazur, Alexander; McCotter, Craig; Woodard, Pamela K; Rosenthal, Lawrence; Johnson, Whitney; Mela, Theofanie

    2016-02-01

    Permanent cardiac pacemakers have historically been considered a contraindication to magnetic resonance imaging (MRI). The purpose of the ProMRI Phase B Study, a multicenter, prospective, single-arm, nonrandomized study, was to evaluate the clinical safety of the Biotronik ProMRI pacemaker system in patients undergoing thoracic spine and cardiac MRI. The ProMRI Phase B study enrolled 245 patients with stable baseline pacing indices implanted with an Entovis pacemaker (DR-T or SR-T) and Setrox 53-cm and/or 60-cm lead(s). Device interrogation was performed at enrollment, pre- and post-MRI scan, and 1 and 3 months post-MRI. End-points were (1) freedom from MRI- and pacing system-related serious adverse device effects through 1 month post-MRI; (2) freedom from atrial and ventricular MRI-induced pacing threshold increase (>0.5 V); and (3) freedom from P- and R-wave amplitude attenuation (<50%), or P wave <1.5 mV, or R wave <5.0 mV at 1 month post-MRI. In total, 216 patients completed the MRI and 1-month post-MRI follow-up. One adverse event possibly related to the implanted system and the MRI procedure occurred, resulting in a serious adverse device effect-free rate of 99.6% (220/221; P < .0001. Freedom from atrial and ventricular pacing threshold increase was 100% (194/194, P < .001) and 100% (206/206, P < .001) respectively. Freedom from P- and R-wave amplitude attenuation was 98.2% (167/170, P < .001) and 100% (188/188, P < .001) respectively. The results of the ProMRI Phase B study demonstrate the clinical safety and efficacy of the ProMRI pacemaker system in patients subjected to thoracic spine and cardiac MRI conditions. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  16. Spatial and Working Memory Is Linked to Spine Density and Mushroom Spines

    PubMed Central

    Aher, Yogesh D.; Sase, Ajinkya; Gröger, Marion; Mokhtar, Maher; Höger, Harald; Lubec, Gert

    2015-01-01

    Background Changes in synaptic structure and efficacy including dendritic spine number and morphology have been shown to underlie neuronal activity and size. Moreover, the shapes of individual dendritic spines were proposed to correlate with their capacity for structural change. Spine numbers and morphology were reported to parallel memory formation in the rat using a water maze but, so far, there is no information on spine counts or shape in the radial arm maze (RAM), a frequently used paradigm for the evaluation of complex memory formation in the rodent. Methods 24 male Sprague-Dawley rats were divided into three groups, 8 were trained, 8 remained untrained in the RAM and 8 rats served as cage controls. Dendritic spine numbers and individual spine forms were counted in CA1, CA3 areas and dentate gyrus of hippocampus using a DIL dye method with subsequent quantification by the Neuronstudio software and the image J program. Results Working memory errors (WME) and latency in the RAM were decreased along the training period indicating that animals performed the task. Total spine density was significantly increased following training in the RAM as compared to untrained rats and cage controls. The number of mushroom spines was significantly increased in the trained as compared to untrained and cage controls. Negative significant correlations between spine density and WME were observed in CA1 basal dendrites and in CA3 apical and basal dendrites. In addition, there was a significant negative correlation between spine density and latency in CA3 basal dendrites. Conclusion The study shows that spine numbers are significantly increased in the trained group, an observation that may suggest the use of this method representing a morphological parameter for memory formation studies in the RAM. Herein, correlations between WME and latency in the RAM and spine density revealed a link between spine numbers and performance in the RAM. PMID:26469788

  17. Bone mineral density level by dual energy X-ray absorptiometry in rheumatoid arthritis.

    PubMed

    Makhdoom, Asadullah; Rahopoto, Muhammad Qasim; Awan, Shazia; Tahir, Syed Muhammad; Memon, Shazia; Siddiqui, Khaleeque Ahmed

    2017-01-01

    To observe the level of bone mineral density by Dual Energy X-ray Absorptiometry in rheumatoid arthritis patients. The observational study was conducted at Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan, from January 2011 to December 2014. Bone mineral density was measured from the femoral neck, ward's triangle and lumbar spine, in patients 25-55 years of age, who were diagnosed with rheumatoid arthritis. All the cases were assessed for bone mineral density from appendicular as well as axial skeleton. Data was collected through a designed proforma and analysis was performed using SPSS 21. Of the 229 rheumatoid arthritis patients, 33(14.4%) were males. Five (15.1%) males had normal bone density, 14(42.4%) had osteopenia and 14(42.4%) had osteoporosis. Of the 196(85.5%) females, 45(29.9%) had normal bone density, 72 (37.7%) had osteopenia and 79(40.30%) had osteoporosis. Of the 123(53.7%) patients aged 30-50 years, 38(30.9%) had normal bone density, 59(48.0%) had osteopenia, and 26(21.1%) had osteoporosis. Of the 106(46.3%) patients over 50 years, 12(11.3%) had normal bone density, 27 (25.5%) had osteopenia and 67(63.2%) had osteoporosis. Osteoporosis and osteopenia were most common among rheumatoid arthritis patients. Assessment of bone mineral density by Dual Energy X-ray Absorptiometry can lead to quick relief in the clinical symptoms with timely therapy.

  18. Three-dimensional sampling perfection with application-optimised contrasts using a different flip angle evolutions sequence for routine imaging of the spine: preliminary experience

    PubMed Central

    Tins, B; Cassar-Pullicino, V; Haddaway, M; Nachtrab, U

    2012-01-01

    Objectives The bulk of spinal imaging is still performed with conventional two-dimensional sequences. This study assesses the suitability of three-dimensional sampling perfection with application-optimised contrasts using a different flip angle evolutions (SPACE) sequence for routine spinal imaging. Methods 62 MRI examinations of the spine were evaluated by 2 examiners in consensus for the depiction of anatomy and presence of artefact. We noted pathologies that might be missed using the SPACE sequence only or the SPACE and a sagittal T1 weighted sequence. The reference standards were sagittal and axial T1 weighted and T2 weighted sequences. At a later date the evaluation was repeated by one of the original examiners and an additional examiner. Results There was good agreement of the single evaluations and consensus evaluation for the conventional sequences: κ>0.8, confidence interval (CI)>0.6–1.0. For the SPACE sequence, depiction of anatomy was very good for 84% of cases, with high interobserver agreement, but there was poor interobserver agreement for other cases. For artefact assessment of SPACE, κ=0.92, CI=0.92–1.0. The SPACE sequence was superior to conventional sequences for depiction of anatomy and artefact resistance. The SPACE sequence occasionally missed bone marrow oedema. In conjunction with sagittal T1 weighted sequences, no abnormality was missed. The isotropic SPACE sequence was superior to conventional sequences in imaging difficult anatomy such as in scoliosis and spondylolysis. Conclusion The SPACE sequence allows excellent assessment of anatomy owing to high spatial resolution and resistance to artefact. The sensitivity for bone marrow abnormalities is limited. PMID:22374284

  19. Three-dimensional sampling perfection with application-optimised contrasts using a different flip angle evolutions sequence for routine imaging of the spine: preliminary experience.

    PubMed

    Tins, B; Cassar-Pullicino, V; Haddaway, M; Nachtrab, U

    2012-08-01

    The bulk of spinal imaging is still performed with conventional two-dimensional sequences. This study assesses the suitability of three-dimensional sampling perfection with application-optimised contrasts using a different flip angle evolutions (SPACE) sequence for routine spinal imaging. 62 MRI examinations of the spine were evaluated by 2 examiners in consensus for the depiction of anatomy and presence of artefact. We noted pathologies that might be missed using the SPACE sequence only or the SPACE and a sagittal T(1) weighted sequence. The reference standards were sagittal and axial T(1) weighted and T(2) weighted sequences. At a later date the evaluation was repeated by one of the original examiners and an additional examiner. There was good agreement of the single evaluations and consensus evaluation for the conventional sequences: κ>0.8, confidence interval (CI)>0.6-1.0. For the SPACE sequence, depiction of anatomy was very good for 84% of cases, with high interobserver agreement, but there was poor interobserver agreement for other cases. For artefact assessment of SPACE, κ=0.92, CI=0.92-1.0. The SPACE sequence was superior to conventional sequences for depiction of anatomy and artefact resistance. The SPACE sequence occasionally missed bone marrow oedema. In conjunction with sagittal T(1) weighted sequences, no abnormality was missed. The isotropic SPACE sequence was superior to conventional sequences in imaging difficult anatomy such as in scoliosis and spondylolysis. The SPACE sequence allows excellent assessment of anatomy owing to high spatial resolution and resistance to artefact. The sensitivity for bone marrow abnormalities is limited.

  20. Imaging of Herniated Discs of the Cervical Spine: Inter-Modality Differences between 64-Slice Multidetector CT and 1.5-T MRI

    PubMed Central

    Yi, Ji Sook; Han, Jong Kyu; Kim, Hyun-Joo

    2015-01-01

    Objective To assess inter-modality variability when evaluating cervical intervertebral disc herniation using 64-slice multidetector-row computed tomography (MDCT) and magnetic resonance imaging (MRI). Materials and Methods Three musculoskeletal radiologists independently reviewed cervical spine 1.5-T MRI and 64-slice MDCT data on C2-3 though C6-7 of 51 patients in the context of intervertebral disc herniation. Interobserver and inter-modality agreements were expressed as unweighted kappa values. Weighted kappa statistics were used to assess the extents of agreement in terms of the number of involved segments (NIS) in disc herniation and epicenter measurements collected using MDCT and MRI. Results The interobserver agreement rates upon evaluation of disc morphology by the three radiologists were in fair to moderate agreement (k = 0.39-0.53 for MDCT images; k = 0.45-0.56 for MRIs). When the disc morphology was categorized into two and four grades, the inter-modality agreement rates were moderate (k-value, 0.59) and substantial (k-value, 0.66), respectively. The inter-modality agreements for evaluations of the NIS (k-value, 0.78) and the epicenter (k-value, 0.79) were substantial. Also, the interobserver agreements for the NIS (CT; k-value, 0.85 and MRI; k-value, 0.88) and epicenter (CT; k-value, 0.74 and MRI; k-value, 0.70) evaluations by two readers were substantial. MDCT tended to underestimate the extent of herniated disc lesions compared with MRI. Conclusion Multidetector-row computed tomography and MRI showed a moderate-to-substantial degree of inter-modality agreement for the assessment of herniated cervical discs. MDCT images have a tendency to underestimate the anterior/posterior extent of the herniated disc compared with MRI. PMID:26175589

  1. A sonographic approach to prenatal classification of congenital spine anomalies

    PubMed Central

    Robertson, Meiri; Sia, Sock Bee

    2015-01-01

    Abstract Objective: To develop a classification system for congenital spine anomalies detected by prenatal ultrasound. Methods: Data were collected from fetuses with spine abnormalities diagnosed in our institution over a five‐year period between June 2005 and June 2010. The ultrasound images were analysed to determine which features were associated with different congenital spine anomalies. Findings of the prenatal ultrasound images were correlated with other prenatal imaging, post mortem findings, post mortem imaging, neonatal imaging, karyotype, and other genetic workup. Data from published case reports of prenatal diagnosis of rare congenital spine anomalies were analysed to provide a comprehensive work. Results: During the study period, eighteen cases of spine abnormalities were diagnosed in 7819 women. The mean gestational age at diagnosis was 18.8w ± 2.2 SD. While most cases represented open NTD, a spectrum of vertebral abnormalities were diagnosed prenatally. These included hemivertebrae, block vertebrae, cleft or butterfly vertebrae, sacral agenesis, and a lipomeningocele. The most sensitive features for diagnosis of a spine abnormality included flaring of the vertebral arch ossification centres, abnormal spine curvature, and short spine length. While reported findings at the time of diagnosis were often conservative, retrospective analysis revealed good correlation with radiographic imaging. 3D imaging was found to be a valuable tool in many settings. Conclusions: Analysis of the study findings showed prenatal ultrasound allowed detection of disruption to the normal appearances of the fetal spine. Using the three features of flaring of the vertebral arch ossification centres, abnormal spine curvature, and short spine length, an algorithm was devised to aid with the diagnosis of spine anomalies for those who perform and report prenatal ultrasound. PMID:28191204

  2. Biochemical validity of imaging techniques (X-ray, MRI, and dGEMRIC) in degenerative disc disease of the human cervical spine-an in vivo study.

    PubMed

    Bostelmann, Richard; Bostelmann, Tamara; Nasaca, Adrian; Steiger, Hans Jakob; Zaucke, Frank; Schleich, Christoph

    2017-02-01

    On a molecular level, maturation or degeneration of human intervertebral disc is among others expressed by the content of glycosaminoglycans (GAGs). According to the degenerative status, the disc content can differ in nucleus pulposus (NP) and annulus fibrosus (AF), respectively. Research in this area was conducted mostly on postmortem samples. Although several radiological classification systems exist, none includes biochemical features. Therefore, we focused our in vivo study on a widely spread and less expensive imaging technique for the cervical spine and the correlation of radiological patterns to biochemical equivalents in the intervertebral discs. The aim of this pilot study was to (1) measure the GAG content in human cervical discs, (2) to investigate whether a topographic biochemical GAG pattern can be found, and (3) whether there is a correlation between imaging data (X-ray and magnetic resonance imaging [MRI] including delayed gadolinium-enhanced MRI of cartilage [dGEMRIC] as a special imaging technique of cartilage) and the biochemical data. We conducted a prospective experimental pilot study. Only non-responders to conservative therapy were included. All subjects were physically and neurologically examined, and they completed their questionnaires. Visual analogue scale neck and arm, Neck Disability Index score, radiological parameters (X-rays, MRI, dGEMRIC), and the content of GAG in the cervical disc were assessed. After surgical removal of 12 discs, 96 fractions of AF and NP were biochemically analyzed for the GAG content using dimethylmethylene blue assay. A quantitative pattern of GAGs in the human cervical disc was identified. There were (1) significantly (p<.001) higher values of GAGs (µg GAG/mg tissue) in the NP (169.9 SD 37.3) compared with the AF (132.4 SD 42.2), and (2) significantly (p<.005) higher values of GAGs in the posterior (right/left: 149.9/160.2) compared with the anterior (right/left: 112.0/120.2) part of the AF. Third, we found

  3. Inter-operator Reliability of Magnetic Resonance Image-Based Computational Fluid Dynamics Prediction of Cerebrospinal Fluid Motion in the Cervical Spine.

    PubMed

    Martin, Bryn A; Yiallourou, Theresia I; Pahlavian, Soroush Heidari; Thyagaraj, Suraj; Bunck, Alexander C; Loth, Francis; Sheffer, Daniel B; Kröger, Jan Robert; Stergiopulos, Nikolaos

    2016-05-01

    For the first time, inter-operator dependence of MRI based computational fluid dynamics (CFD) modeling of cerebrospinal fluid (CSF) in the cervical spinal subarachnoid space (SSS) is evaluated. In vivo MRI flow measurements and anatomy MRI images were obtained at the cervico-medullary junction of a healthy subject and a Chiari I malformation patient. 3D anatomies of the SSS were reconstructed by manual segmentation by four independent operators for both cases. CFD results were compared at nine axial locations along the SSS in terms of hydrodynamic and geometric parameters. Intraclass correlation (ICC) assessed the inter-operator agreement for each parameter over the axial locations and coefficient of variance (CV) compared the percentage of variance for each parameter between the operators. Greater operator dependence was found for the patient (0.19 < ICC < 0.99) near the craniovertebral junction compared to the healthy subject (ICC > 0.78). For the healthy subject, hydraulic diameter and Womersley number had the least variance (CV = ~2%). For the patient, peak diastolic velocity and Reynolds number had the smallest variance (CV = ~3%). These results show a high degree of inter-operator reliability for MRI-based CFD simulations of CSF flow in the cervical spine for healthy subjects and a lower degree of reliability for patients with Type I Chiari malformation.

  4. Inter-Operator Dependence of Magnetic Resonance Image-Based Computational Fluid Dynamics Prediction of Cerebrospinal Fluid Motion in the Cervical Spine

    PubMed Central

    Martin, Bryn A.; Yiallourou, Theresia I.; Pahlavian, Soroush Heidari; Thyagaraj, Suraj; Bunck, Alexander C.; Loth, Francis; Sheffer, Daniel B.; Kröger, Jan Robert; Stergiopulos, Nikolaos

    2015-01-01

    For the first time, inter-operator dependence of MRI based computational fluid dynamics (CFD) modeling of cerebrospinal fluid (CSF) in the cervical spinal subarachnoid space (SSS) is evaluated. In vivo MRI flow measurements and anatomy MRI images were obtained at the cervico-medullary junction of a healthy subject and a Chiari I malformation patient. 3D anatomies of the SSS were reconstructed by manual segmentation by four independent operators for both cases. CFD results were compared at nine axial locations along the SSS in terms of hydrodynamic and geometric parameters. Intraclass correlation (ICC) assessed the inter-operator agreement for each parameter over the axial locations and coefficient of variance (CV) compared the percentage of variance for each parameter between the operators. Greater operator dependence was found for the patient (0.19 0.78). For the healthy subject, hydraulic diameter and Womersley number had the least variance (CV= ~2%). For the patient, peak diastolic velocity and Reynolds number had the smallest variance (CV= ~3%). These results show a high degree of inter-operator reliability for MRI-based CFD simulations of CSF flow in the cervical spine for healthy subjects and a lower degree of reliability for patients with Type I Chiari malformation. PMID:26446009

  5. Evaluation and management of 2 ferocactus spines in the orbit.

    PubMed

    Russell, David J; Kim, Tim I; Kubis, Kenneth

    2013-01-01

    A 49-year-old woman, who had fallen face first in a cactus 1 week earlier, presented with a small, mobile, noninflamed subcutaneous nodule at the rim of her right lateral orbit with no other functional deficits. A CT scan was obtained, which revealed a 4-cm intraorbital tubular-shaped foreign body resembling a large cactus spine. A second preoperative CT scan, obtained for an intraoperative guidance system, demonstrated a second cactus spine, which was initially not seen on the first CT scan. Both spines were removed surgically without complication. The authors discuss factors that can cause diagnosis delay, review the radiographic features of cactus spines, and discuss the often times benign clinical course of retained cactus spine foreign bodies. To the authors' knowledge, this is the first case report of cactus spines in the orbit. Health-care professionals should have a low threshold for imaging in cases of traumatic injuries involving cactus spines.

  6. Total body composition by dual-photon (153Gd) absorptiometry

    SciTech Connect

    Mazess, R.B.; Peppler, W.W.; Gibbons, M.

    1984-10-01

    The lean-fat composition (%FATR) of soft tissue and the mineral mass of the skeleton were determined in vivo using dual-photon (153Gd) absorptiometry (dose under 2 mrem). A rectilinear raster scan was made over the entire body in 18 subjects (14 female, 4 male). Single-photon absorptiometry (125I) measured bone mineral content on the radius. Percentage fat (%FATD) was determined in the same subjects using body density (from underwater weighing with correction for residual lung volume). Lean body mass (LBM) was determined using both %FATR and %FATD. Percentage fat from absorptiometry and from underwater density were correlated (r . 0.87). The deviationmore » of %FATD from %FATR was due to the amount of skeletal mineral as a percentage of the LBM (r . 0.90). Therefore, skeletal variability, even in normal subjects, where mineral ranges only from 4 to 8% of the LBM, essentially precludes use of body density as a composition indicator unless skeletal mass is measured. Anthropometry (fatfolds and weight) predicted %FATR and LBM at least as well as did underwater density. The predictive error of %FATR from fatfolds was 5% while the predictive error in predicting LBM from anthropometry was 2 to 3 kg (3%).« less

  7. Use of dual-energy X-ray absorptiometry (DXA) for diagnosis and fracture risk assessment; WHO-criteria, T- and Z-score, and reference databases.

    PubMed

    Dimai, Hans P

    2017-11-01

    Dual-energy X-ray absorptiometry (DXA) is a two-dimensional imaging technology developed to assess bone mineral density (BMD) of the entire human skeleton and also specifically of skeletal sites known to be most vulnerable to fracture. In order to simplify interpretation of BMD measurement results and allow comparability among different DXA-devices, the T-score concept was introduced. This concept involves an individual's BMD which is then compared with the mean value of a young healthy reference population, with the difference expressed as a standard deviation (SD). Since the early nineties of the past century, the diagnostic categories "normal, osteopenia, and osteoporosis", as recommended by a WHO working Group, are based on this concept. Thus, DXA is still the globally accepted "gold-standard" method for the noninvasive diagnosis of osteoporosis. Another score obtained from DXA measurement, termed Z-score, describes the number of SDs by which the BMD in an individual differs from the mean value expected for age and sex. Although not intended for diagnosis of osteoporosis in adults, it nevertheless provides information about an individual's fracture risk compared to peers. DXA measurement can either be used as a "stand-alone" means in the assessment of an individual's fracture risk, or incorporated into one of the available fracture risk assessment tools such as FRAX® or Garvan, thus improving the predictive power of such tools. The issue which reference databases should be used by DXA-device manufacturers for T-score reference standards has been recently addressed by an expert group, who recommended use National Health and Nutrition Examination Survey III (NHANES III) databases for the hip reference standard but own databases for the lumbar spine. Furthermore, in men it is recommended use female reference databases for calculation of the T-score and use male reference databases for calculation of Z-score. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Spine centerline extraction and efficient spine reading of MRI and CT data

    NASA Astrophysics Data System (ADS)

    Lorenz, C.; Vogt, N.; Börnert, P.; Brosch, T.

    2018-03-01

    Radiological assessment of the spine is performed regularly in the context of orthopedics, neurology, oncology, and trauma management. Due to the extension and curved geometry of the spinal column, reading is time-consuming and requires substantial user interaction to navigate through the data during inspection. In this paper a spine geometry guided viewing approach is proposed facilitating reading by reducing the degrees of freedom to be manipulated during inspection of the data. The method is using the spine centerline as a representation of the spine geometry. We assume that renderings most useful for reading are those that can be locally defined based on a rotation and translation relative to the spine centerline. The resulting renderings conserve locally the relation to the spine and lead to curved planar reformats that can be adjusted using a small set of parameters to minimize user interaction. The spine centerline is extracted by an automated image to image foveal fully convolutional neural network (FFCN) based approach. The network consists of three parallel convolutional pathways working on different levels of resolution and processed fields of view. The outputs of the parallel pathways are combined by a subsequent feature integration pathway to yield the (final) centerline probability map, which is converted into a set of spine centerline points. The network has been trained separately using two data set types, one comprising a mixture of T1 and T2 weighted spine MR images and one using CT image data. We achieve an average centerline position error of 1.7 mm for MR and 0.9 mm for CT and a DICE coefficient of 0.84 for MR and 0.95 for CT. Based on the thus obtained centerline viewing and multi-planar reformatting can be easily facilitated.

  9. Investigation of the reproducibility and reliability of sagittal vertebral inclination measurements from MR images of the spine.

    PubMed

    Vrtovec, Tomaž; Pernuš, Franjo; Likar, Boštjan

    2014-10-01

    In this study, sagittal vertebral inclination (SVI) was systematically evaluated for 28 vertebrae (segments between T4 and L5) in magnetic resonance (MR) images of one normal and one scoliotic subject to compare the performance of manual and computerized measurements, and identify the most reproducible and reliable measurements. Manual measurements were performed by three observers, who identified on two occasions the distinctive anatomical landmarks required to evaluate SVI by six measurement methods, i.e. the superior tangents, inferior tangents, anterior tangents, posterior tangents, mid-endplate lines and mid-wall lines. Computerized measurements were performed by automatically evaluating SVI from the symmetry of vertebral anatomical structures in two-dimensional (2D) sagittal cross-sections and in three-dimensional (3D) volumetric images. The mid-wall lines and posterior tangents proved to be the manual measurements with the lowest intra-observer (standard deviation, SD, of 1.4° and 1.7°, respectively) and inter-observer variability (SD of 1.9° and 2.4°, respectively). The strongest inter-method agreement was found between the mid-wall lines and posterior tangents (SD of 2.0°). Computerized measurements in 2D and in 3D resulted in intra-observer (SD of 2.8° and 3.1°, respectively) and inter-observer variability (SD of 3.8° and 5.2°, respectively) that were comparable to those of the superior tangents (SD of 2.6° and 3.7°) and inferior tangents (SD of 3.2° and 4.5°), which represent standard Cobb angle measurements. It can be concluded that computerized measurements of SVI should be based on the inclination of vertebral body walls. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Spine mineral change during osteoporosis therapy

    SciTech Connect

    Powell, M.R.; Kolb, F.O.; Meier, K.A.

    1985-05-01

    Osteoporosis therapy has been handicapped by lack of means to quantitate the process. Dual photon absorptiometry (DPA) offers accurate (4%) and precise (2%) estimation of lumbar spine mineral. The authors followed 42 osteoporotics to determine response to therapy. There were 17 patients with normal menopause (NM), 4 with surgical menopause (SM), 3 with premature menopause (PM), and 18 with idiopathic osteoporoses (10). Intervals between DPA spine mineral estimation were 16.5 +- 5.2 mo. for NM, 14.3 +- 8.4 mo. for SM, 14.0 +- 7.5 mo. for PM and 16.7 +- 5.8 mo. for 10. Observed average percent change of spinemore » mineral under therapy for those intervals was 5.2 +- 7.9% for NM, +7.3 +- 1.7% for SM, -2.4 +- 6.3% for PM and +1.8 +- 12.3% for 10. Therapy invariably was with Ca, low dose Premarin in NM and PM, often with phosphates in IO, sometimes with thiazides, often with Vitamin D and with occasional other modalities, including NaF. The authors find DPA is a cost-effective way to measure osteopenia in the osteoporeses, document response to therapy, identify need for therapy change when there is continued bone loss under therapy, and to encourage the patient's compliance with long-term, complex therapies.« less

  11. Prospective analysis of magnetic resonance imaging accuracy in diagnosing traumatic injuries of the posterior ligamentous complex of the thoracolumbar spine.

    PubMed

    Pizones, Javier; Sánchez-Mariscal, Felisa; Zúñiga, Lorenzo; Álvarez, Patricia; Izquierdo, Enrique

    2013-04-20

    Prospective cohort study. To study magnetic resonance imaging (MRI) accuracy in diagnosing posterior ligamentous complex (PLC) damage, when applying the new dichotomic instability criteria in a prospective cohort of patients with vertebral fracture. Recent studies dispute MRI accuracy to diagnose PLC injuries. They analyze the complex based on 3 categories (intact/indeterminate/rupture), including the indeterminate in the ruptured group (measurement bias) in the accuracy analysis. Moreover, fractures with conservative treatment (selection bias) are not included. Both facts reduce the specificity. A recent study has proposed new criteria where posterior instability is determined with supraspinous ligament (SSL) rupture. Prospective study of patients with acute thoracolumbar fracture, using radiography and MRI (FS-T2-w/short-tau inversion-recovery sequences). 1. The integrity (ruptured/unruptured) of each isolated component of the PLC (facet capsules, interspinous ligament, SSL, and ligamentum flavum) was assessed via MRI and surgical findings. 2. PLC integrity as a whole was assessed, adopting the new dichotomic stability criteria from previous studies. In the MR images, PLC is considered ruptured when the SSL is found discontinued, and intact when not (this excludes the "indeterminate" category). In surgically treated fractures, PLC stability as a whole was assessed dynamically (ruptured/unruptured). In conservative fractures, PLC stability was assessed according to change in vertebral kyphosis measured with the local kyphotic angle at 2-year follow-up (ruptured if difference is > 5°/unruptured if difference is < 5°).3. Comparative analysis among findings provided MRI accuracy in diagnosing PLC damage. Fifty-eight vertebral fractures were studied (38 surgical, 20 conservative), of which 50% were in males; average age, 40.4 years. MRI sensitivity for injury diagnosis of each isolated PLC component varied between 92.3% (interspinous ligament) and 100% (ligamentum

  12. Volume of Lytic Vertebral Body Metastatic Disease Quantified Using Computed Tomography–Based Image Segmentation Predicts Fracture Risk After Spine Stereotactic Body Radiation Therapy

    SciTech Connect

    Thibault, Isabelle; Department of Radiation Oncology, Centre Hospitalier de L'Universite de Québec–Université Laval, Quebec, Quebec; Whyne, Cari M.

    Purpose: To determine a threshold of vertebral body (VB) osteolytic or osteoblastic tumor involvement that would predict vertebral compression fracture (VCF) risk after stereotactic body radiation therapy (SBRT), using volumetric image-segmentation software. Methods and Materials: A computational semiautomated skeletal metastasis segmentation process refined in our laboratory was applied to the pretreatment planning CT scan of 100 vertebral segments in 55 patients treated with spine SBRT. Each VB was segmented and the percentage of lytic and/or blastic disease by volume determined. Results: The cumulative incidence of VCF at 3 and 12 months was 14.1% and 17.3%, respectively. The median follow-up was 7.3 months (range,more » 0.6-67.6 months). In all, 56% of segments were determined lytic, 23% blastic, and 21% mixed, according to clinical radiologic determination. Within these 3 clinical cohorts, the segmentation-determined mean percentages of lytic and blastic tumor were 8.9% and 6.0%, 0.2% and 26.9%, and 3.4% and 15.8% by volume, respectively. On the basis of the entire cohort (n=100), a significant association was observed for the osteolytic percentage measures and the occurrence of VCF (P<.001) but not for the osteoblastic measures. The most significant lytic disease threshold was observed at ≥11.6% (odds ratio 37.4, 95% confidence interval 9.4-148.9). On multivariable analysis, ≥11.6% lytic disease (P<.001), baseline VCF (P<.001), and SBRT with ≥20 Gy per fraction (P=.014) were predictive. Conclusions: Pretreatment lytic VB disease volumetric measures, independent of the blastic component, predict for SBRT-induced VCF. Larger-scale trials evaluating our software are planned to validate the results.« less

  13. Magnetic resonance imaging findings of the lumbar spine in elite horseback riders: correlations with back pain, body mass index, trunk/leg-length coefficient, and riding discipline.

    PubMed

    Kraft, Clayton N; Pennekamp, Peter H; Becker, Ute; Young, Mei; Diedrich, Oliver; Lüring, Christian; von Falkenhausen, Makus

    2009-11-01

    Most orthopaedic problems experienced by competitive horseback riders are related to pain in the lower back, hip joint, and hamstring muscles. Riders-especially, show jumpers-are frequently hampered in their performance because of lumbar pain. To date, there has been no research into lumbar disk degeneration in elite competitive riders. Competitive horseback riding accelerates lumbar disk degeneration. Cross-sectional study; Level of evidence, 3. Fifty-eight elite riders (18 men, 40 women; mean age, 32.4 years) and a control group of 30 nonriding volunteers (17 men, 13 women; mean age, 28.7 years) were evaluated for lumbar disk degeneration, cross-sectional area of paraspinal muscles, spondylolysis, and spondylolisthesis, using magnetic resonance imaging (MRI). The prevalence of disk degeneration between the 2 groups was compared, and the relationship was investigated between low back pain (LBP), riding discipline, body mass index (BMI), trunk/leg-length coefficient, and MRI results. Eighty-eight percent of elite riders (n = 51) had a history of LBP, versus 33% of the controls (P < .05). There was no statistical difference for the prevalence of LBP among the different riding disciplines. However, there was a high rate of pathologic T2 signal intensity of the lumbar intervertebral disk among riders-specifically, dressage riders-yet no significant increase when compared with controls. History of LBP symptoms, riding discipline, BMI, and trunk/leg-length ratio had no significant effect on the development of lumbar disk degeneration. Occult fractures of the pars interarticularis and manifest spondylolysis were not seen for any rider. Two controls had spondylolisthesis Meyerding grade 1 not associated with back pain. Although riders have a high prevalence of LBP, there is no conclusive MRI evidence to suggest that the cause lies in undue disk degeneration, spondylolysis, spondylolisthesis, or pathologic changes of the paraspinal muscles of the lumbar spine.

  14. Image-Guided Cryoablation of the Spine in a Swine Model: Clinical, Radiological, and Pathological Findings with Light and Electron Microscopy.

    PubMed

    de Freitas, Ricardo Miguel Costa; Andrade, Celi Santos; Caldas, José Guilherme Mendes Pereira; Tsunemi, Miriam Harumi; Ferreira, Lorraine Braga; Arana-Chavez, Victor Elias; Cury, Patrícia Maluf

    2015-10-01

    This study was designed to present the feasibility of an in vivo image-guided percutaneous cryoablation of the porcine vertebral body. The institutional animal care committee approved this study. Cone-beam computed tomography (CBCT)-guided vertebral cryoablations (n = 22) were performed in eight pigs with short, 2-min, single or double-freezing protocols. Protective measures to nerves included dioxide carbon (CO2) epidural injections and spinal canal temperature monitoring. Clinical, radiological, and pathological data with light (n = 20) or transmission electron (n = 2) microscopic analyses were evaluated after 6 days of clinical follow-up and euthanasia. CBCT/fluoroscopic-guided transpedicular vertebral body cryoprobe positioning and CO2 epidural injection were successful in all procedures. No major complications were observed in seven animals (87.5 %, n = 8). A minor complication was observed in one pig (12.5 %, n = 1). Logistic regression model analysis showed the cryoprobe-spinal canal (Cp-Sc) distance as the most efficient parameter to categorize spinal canal temperatures lower than 19 °C (p < 0.004), with a significant Pearson's correlation test (p < 0.041) between the Cp-Sc distance and the lowest spinal canal temperatures. Ablation zones encompassed pedicles and the posterior wall of the vertebral bodies with an inflammatory rim, although no inflammatory infiltrate was depicted in the surrounding neural structures at light microscopy. Ultrastructural analyses evidenced myelin sheath disruption in some large nerve fibers, although neurological deficits were not observed. CBCT-guided vertebral cryoablation of the porcine spine is feasible under a combination of a short freezing protocol and protective measures to the surrounding nerves. Ultrastructural analyses may be helpful assess the early modifications of the nerve fibers.

  15. MO-FG-CAMPUS-JeP3-02: A Novel Setup Approach to Improve C-Spine Curvature Reproducibility for Head and Neck Radiotherapy Using Optical Surface Imaging with Two Regions of Interest

    SciTech Connect

    Ryan, K; Gil, M; Li, G

    Purpose: To develop a novel approach to improve cervical spine (c-spine) curvature reproducibility for head and neck (HN) patients using optical surface imaging (OSI) with two regions of interests (ROIs). Methods: The OSI-guided, two-step setup procedure requires two ROIs: ROI-1 of the shoulders and ROI-2 of the face. The neck can be stretched or squeezed in superior-inferior (SI) direction using a specially-designed sliding head support. We hypothesize that when these two ROIs are aligned, the c-spine should fall into a naturally reproducible position under same setup conditions. An anthropomorphous phantom test was performed to examine neck pitch angles comparing withmore » the calculated angles. Three volunteers participated in the experiments, which start with conventional HN setup using skin markers and room lasers. An OSI image and lateral photo-picture were acquired as the references. In each of the three replicate tests, conventional setup was first applied after volunteers got on the couch. ROI-1 was aligned by moving the body, followed by ROI-2 alignment via adjusting head position and orientation under real-time OSI guidance. A final static OSI image and lateral picture were taken to evaluate both anterior and posterior surface alignments. Three degrees of freedom can be adjusted if an open-face mask was applied, including head SI shift using the sliding head support and pitch-and-roll rotations using a commercial couch extension. Surface alignment was analyzed comparing with conventional setup. Results: The neck pitch angle measured by OSI is consistent with the calculated (0.2±0.6°). Volunteer study illustrated improved c-spine setup reproducibility using OSI comparing with conventional setup. ROI alignments with 2mm/1° tolerance are achieved within 3 minutes. Identical knee support is important to achieve ROI-1 pitch alignment. Conclusion: The feasibility of this novel approach has been demonstrated for c-spine curvature setup reproducibility

  16. Differences in Site-Specific Fracture Risk Among Older Women with Discordant Results for Osteoporosis at Hip and Spine: the Study of Osteoporotic Fractures

    PubMed Central

    Fink, Howard A.; Harrison, Stephanie L.; Taylor, Brent C.; Cummings, Steven R.; Schousboe, John T.; Kuskowski, Michael A.; Stone, Katie L.; Ensrud, Kristine E.

    2009-01-01

    To examine the fracture pattern in older women whose bone mineral density (BMD) T-score criteria for osteoporosis at hip and spine disagree, hip and spine BMD were measured in Study of Osteoporotic Fractures participants using dual energy x-ray absorptiometry (DXA). Hip osteoporosis was defined as T-score ≤-2.5 at femoral neck or total hip, and spine osteoporosis as T-score ≤-2.5 at lumbar spine. Incident clinical fractures were self-reported and centrally adjudicated. Incident radiographic spine fractures were defined morphometrically. Compared to women with osteoporosis at neither hip nor spine, those osteoporotic only at hip had a 3.0-fold age and weight-adjusted increased risk for hip fracture (95%CI 2.4-3.6), and smaller increases in risk of nonhip nonspine (HR=1.6), clinical spine (OR=2.2), and radiographic spine fractures (OR=1.5). Women osteoporotic only at spine had a 2.8-fold increased odds of radiographic spine fracture (95%CI 2.1-3.8), and smaller increases in risk of clinical spine (OR=1.4), nonhip nonspine (HR=1.6), and hip fractures (HR=1.2). Discordant BMD results predict different fracture patterns. DXA fracture risk estimation in these patients should be site-specific. Women osteoporotic only at spine would not have been identified from hip BMD measurement alone, and may have a sufficiently high fracture risk to warrant preventive treatment. PMID:18296090

  17. The Relationship of Fat Distribution and Insulin Resistance with Lumbar Spine Bone Mass in Women

    PubMed Central

    de Paula, Francisco J. A.; de Araújo, Iana M.; Carvalho, Adriana L.; Elias, Jorge; Salmon, Carlos E. G.; Nogueira-Barbosa, Marcello H.

    2015-01-01

    Bone marrow harbors a significant amount of body adipose tissue (BMAT). While BMAT might be a source of energy for bone modeling and remodeling, its increment can also represent impairment of osteoblast differentiation. The relationship between BMAT, bone mass and insulin sensitivity is only partially understood and seems to depend on the circumstances. The present study was designed to assess the association of BMAT with bone mineral density in the lumbar spine as well as with visceral adipose tissue, intrahepatic lipids, HOMA-IR, and serum levels of insulin and glucose. This cross-sectional clinical investigation included 31 non-diabetic women, but 11 had a pre-diabetes status. Dual X-ray energy absorptiometry was used to measure bone mineral density and magnetic resonance imaging was used to assess fat deposition in BMAT, visceral adipose tissue and liver. Our results suggest that in non-diabetic, there is an inverse relationship between bone mineral density in lumbar spine and BMAT and a trend persists after adjustment for weight, age, BMI and height. While there is a positive association between visceral adipose tissue and intrahepatic lipids with serum insulin levels, there is no association between BMAT and serum levels of insulin. Conversely, a positive relationship was observed between BMAT and serum glucose levels, whereas this association was not observed with other fat deposits. These relationships did not apply after adjustment for body weight, BMI, height and age. The present study shows that in a group of predominantly non-obese women the association between insulin resistance and BMAT is not an early event, as occurs with visceral adipose tissue and intrahepatic lipids. On the other hand, BMAT has a negative relationship with bone mineral density. Taken together, the results support the view that bone has a complex and non-linear relationship with energy metabolism. PMID:26067489

  18. The Relationship of Fat Distribution and Insulin Resistance with Lumbar Spine Bone Mass in Women.

    PubMed

    de Paula, Francisco J A; de Araújo, Iana M; Carvalho, Adriana L; Elias, Jorge; Salmon, Carlos E G; Nogueira-Barbosa, Marcello H

    2015-01-01

    Bone marrow harbors a significant amount of body adipose tissue (BMAT). While BMAT might be a source of energy for bone modeling and remodeling, its increment can also represent impairment of osteoblast differentiation. The relationship between BMAT, bone mass and insulin sensitivity is only partially understood and seems to depend on the circumstances. The present study was designed to assess the association of BMAT with bone mineral density in the lumbar spine as well as with visceral adipose tissue, intrahepatic lipids, HOMA-IR, and serum levels of insulin and glucose. This cross-sectional clinical investigation included 31 non-diabetic women, but 11 had a pre-diabetes status. Dual X-ray energy absorptiometry was used to measure bone mineral density and magnetic resonance imaging was used to assess fat deposition in BMAT, visceral adipose tissue and liver. Our results suggest that in non-diabetic, there is an inverse relationship between bone mineral density in lumbar spine and BMAT and a trend persists after adjustment for weight, age, BMI and height. While there is a positive association between visceral adipose tissue and intrahepatic lipids with serum insulin levels, there is no association between BMAT and serum levels of insulin. Conversely, a positive relationship was observed between BMAT and serum glucose levels, whereas this association was not observed with other fat deposits. These relationships did not apply after adjustment for body weight, BMI, height and age. The present study shows that in a group of predominantly non-obese women the association between insulin resistance and BMAT is not an early event, as occurs with visceral adipose tissue and intrahepatic lipids. On the other hand, BMAT has a negative relationship with bone mineral density. Taken together, the results support the view that bone has a complex and non-linear relationship with energy metabolism.

  19. Magnetic Resonance Imaging (MRI) - Spine

    MedlinePlus

    ... magnetic field of the MRI unit, metal and electronic items are not allowed in the exam room. ... tell the technologist if you have medical or electronic devices in your body. These objects may interfere ...

  20. Meninges of the spine (image)

    MedlinePlus

    ... by 3 connective tissue layers collectively called the meninges. Consisting of the pia mater (closest to the ... the dura mater (farthest from the CNS), the meninges also support blood vessels and contain cerebrospinal fluid. ...

  1. The prevalence of cervical myelopathy among subjects with narrow cervical spinal canal in a population-based magnetic resonance imaging study: the Wakayama Spine Study.

    PubMed

    Nagata, Keiji; Yoshimura, Noriko; Hashizume, Hiroshi; Muraki, Shigeyuki; Ishimoto, Yuyu; Yamada, Hiroshi; Takiguchi, Noboru; Nakagawa, Yukihiro; Minamide, Akihito; Oka, Hiroyuki; Kawaguchi, Hiroshi; Nakamura, Kozo; Akune, Toru; Yoshida, Munehito

    2014-12-01

    A narrow cervical spinal canal (CSC) is a well-known risk factor for cervical myelopathy (CM). However, no epidemiologic data of the CSC based on a population-based cohort are available. The purpose of the study was to investigate the age-related differences in CSC diameters on plain radiographs and to examine the associated magnetic resonance imaging (MRI) abnormalities including cervical cord compression and increased signal intensity (ISI) as well as the clinical CM with the narrow CSC. This was a cross-sectional study. Data were obtained from the baseline survey of the Wakayama Spine Study that was performed from 2008 to 2010 in a western part of Japan. Finally, a total of 959 subjects (319 men and 640 women; mean age, 66.4 years) were included. The outcome measures included in the study were the CSC diameter at C5 level on plain radiographs, cervical cord compression and ISI on sagittal T2-weighted MRI, and physical signs related to CM (eg, the Hoffmann reflex, hyperreflexia of the patellar tendon, the Babinski reflex, sensory and motor function, and bowel/bladder symptoms). The age-related differences of CSC diameters in men and women were investigated by descriptive statistics. The prevalence of MRI abnormalities and clinical CM was compared among the groups divided by the CSC diameter (less than 13, 13-15, and 15 mm or more). In addition, a logistic regression analysis was performed to determine the association of the CSC diameter with cervical cord compression/clinical CM after overall adjustment for age, sex, and body mass index. The CSC diameter was narrower with increasing age in both men and women. The prevalence of cervical cord compression, ISI, and the clinical CM was significantly higher in the narrower CSC group. The prevalence of cervical cord compression, ISI, and CM among subjects with CSC diameter less than 13 mm was 38.0%, 5.4%, and 10.1%, respectively. In the logistic model, the CSC diameter was a significant predictive factor for the

  2. Management of thoracolumbar spine trauma: An overview

    PubMed Central

    Rajasekaran, S; Kanna, Rishi Mugesh; Shetty, Ajoy Prasad

    2015-01-01

    Thoracolumbar spine fractures are common injuries that can result in significant disability, deformity and neurological deficit. Controversies exist regarding the appropriate radiological investigations, the indications for surgical management and the timing, approach and type of surgery. This review provides an overview of the epidemiology, biomechanical principles, radiological and clinical evaluation, classification and management principles. Literature review of all relevant articles published in PubMed covering thoracolumbar spine fractures with or without neurologic deficit was performed. The search terms used were thoracolumbar, thoracic, lumbar, fracture, trauma and management. All relevant articles and abstracts covering thoracolumbar spine fractures with and without neurologic deficit were reviewed. Biomechanically the thoracolumbar spine is predisposed to a higher incidence of spinal injuries. Computed tomography provides adequate bony detail for assessing spinal stability while magnetic resonance imaging shows injuries to soft tissues (posterior ligamentous complex [PLC]) and neurological structures. Different classification systems exist and the most recent is the AO spine knowledge forum classification of thoracolumbar trauma. Treatment includes both nonoperative and operative methods and selected based on the degree of bony injury, neurological involvement, presence of associated injuries and the integrity of the PLC. Significant advances in imaging have helped in the better understanding of thoracolumbar fractures, including information on canal morphology and injury to soft tissue structures. The ideal classification that is simple, comprehensive and guides management is still elusive. Involvement of three columns, progressive neurological deficit, significant kyphosis and canal compromise with neurological deficit are accepted indications for surgical stabilization through anterior, posterior or combined approaches. PMID:25593358

  3. Screening via CT angiogram after traumatic cervical spine fractures: narrowing imaging to improve cost effectiveness. Experience of a Level I trauma center

    PubMed Central

    Lockwood, Megan M.; Smith, Gabriel A.; Tanenbaum, Joseph; Lubelski, Daniel; Seicean, Andreea; Pace, Jonathan; Benzel, Edward C.; Mroz, Thomas E.; Steinmetz, Michael P.

    2017-01-01

    OBJECT Screening for vertebral artery injury (VAI) following cervical spine fractures is routinely performed across trauma centers in North America. From 2002 to 2007, the total number of neck CT angiography (CTA) studies performed in the Medicare population after trauma increased from 9796 to 115,021. In the era of cost-effective medical care, the authors aimed to evaluate the utility of CTA screening in detecting VAI and reduce chances of posterior circulation strokes after traumatic cervical spine fractures. METHODS A retrospective review of all patients presenting with cervical spine fractures to Northeast Ohio’s Level I trauma institution from 2002 to 2012 was performed. RESULTS There was a total of 1717 cervical spine fractures in patients presenting to Northeast Ohio’s Level I trauma institution between 2002 and 2012. CTA screening was performed in 732 patients, and 51 patients (0.7%) were found to have a VAI. Fracture patterns with increased odds of VAI were C-1 and C-2 combined fractures, transverse foramen fractures, and subluxation of adjacent vertebral levels. Ten posterior circulation strokes were identified in this patient population (0.6%) and found in only 4 of 51 cases of VAI (7.8%). High-risk fractures defined by Denver Criteria, VAI, and antiplatelet treatment of VAI were not independent predictors of stroke. CONCLUSIONS Cost-effective screening must be reevaluated in the setting of blunt cervical spine fractures on a case-by-case basis. Further prospective studies must be performed to elucidate the utility of screening for VAI and posterior circulation stroke prevention, if identified. PMID:26613284

  4. North American Spine Society

    MedlinePlus

    ... Articles Policy & Regulation Centers for Medicare & Medicaid Service Food & Drug Administration Scientific & Policy Comments Coverage Recommendations About Coverage Recommendations Access eBook Payor Access Practice Management Market Your Practice Career Center Spine Fellowship Directory ...

  5. Statistical shape modelling of hip and lumbar spine morphology and their relationship in the MRC National Survey of Health and Development.

    PubMed

    Pavlova, Anastasia V; Saunders, Fiona R; Muthuri, Stella G; Gregory, Jennifer S; Barr, Rebecca J; Martin, Kathryn R; Hardy, Rebecca J; Cooper, Rachel; Adams, Judith E; Kuh, Diana; Aspden, Richard M

    2017-08-01

    The anatomical shape of bones and joints is important for their proper function but quantifying this, and detecting pathological variations, is difficult to do. Numerical descriptions would also enable correlations between joint shapes to be explored. Statistical shape modelling (SSM) is a method of image analysis employing pattern recognition statistics to describe and quantify such shapes from images; it uses principal components analysis to generate modes of variation describing each image in terms of a set of numerical scores after removing global size variation. We used SSM to quantify the shapes of the hip and the lumbar spine in dual-energy x-ray absorptiometry (DXA) images from 1511 individuals in the MRC National Survey of Health and Development at ages 60-64 years. We compared shapes of both joints in men and women and hypothesised that hip and spine shape would be strongly correlated. We also investigated associations with height, weight, body mass index (BMI) and local (hip or lumber spine) bone mineral density. In the hip, all except one of the first 10 modes differed between men and women. Men had a wider femoral neck, smaller neck-shaft angle, increased presence of osteophytes and a loss of the femoral head/neck curvature compared with women. Women presented with a flattening of the femoral head and greater acetabular coverage of the femoral head. Greater weight was associated with a shorter, wider femoral neck and larger greater and lesser trochanters. Taller height was accompanied by a flattening of the curve between superior head and neck and a larger lesser trochanter. Four of the first eight modes describing lumbar spine shape differed between men and women. Women tended to have a more lordotic spine than men with relatively smaller but caudally increasing anterior-posterior (a-p) vertebral diameters. Men were more likely to have a straighter spine with larger vertebral a-p diameters relative to vertebral height than women, increasing cranially

  6. Cervical spine injuries in rugby players.

    PubMed Central

    Sovio, O. M.; Van Peteghem, P. K.; Schweigel, J. F.

    1984-01-01

    Nine patients with serious cervical spine injuries that occurred while they were playing rugby were seen in a British Columbia acute spinal cord injury unit during the period 1975-82. All the injuries had occurred during the "scrum" or the "tackle". Two of the patients were rendered permanently quadriplegic, and one patient died. There is a need for a central registry that would record all cervical spine injuries in rugby players as well as for changes in the rules of the game. Images Fig. 1 PMID:6697282

  7. Back pain and degenerative abnormalities in the spine of young elite divers: a 5-year follow-up magnetic resonance imaging study.

    PubMed

    Baranto, Adad; Hellström, Mikael; Nyman, Rickard; Lundin, Olof; Swärd, Leif

    2006-09-01

    Several studies have been published on disc degeneration among young athletes in sports with great demands on the back, but few on competitive divers; however, there are no long-term follow-up studies. Twenty elite divers between 10 and 21 years of age, with the highest possible national ranking, were selected at random without knowledge of previous or present back injuries or symptoms for an MRI study of the thoraco-lumbar spine in a 5-year longitudinal study. The occurrence of MRI abnormalities and their correlation with back pain were evaluated. Eighty-nine percent of the divers had a history of back pain and the median age at the first episode of back pain was 15 years. Sixty-five percent of the divers had MRI abnormalities in the thoraco-lumbar spine already at baseline. Only one diver without abnormalities at baseline had developed abnormalities at follow-up. Deterioration of any type of abnormality was found in 9 of 17 (53%) divers. Including all disc levels in all divers, the total number of abnormalities increased by 29% at follow-up, as compared to baseline. The most common abnormalities were reduced disc signal, Schmorl's nodes, and disc height reduction. Since almost all divers had previous or present back pain, a differentiated analysis of the relationship between pain and MRI findings was not possible. However, the high frequency of both back pain and MRI changes suggests a causal relationship. In conclusion, elite divers had high frequency of back pain at young ages and they run a high risk of developing degenerative abnormalities of the thoraco-lumbar spine, probably due to injuries to the spine during the growth spurt.

  8. Kinematic Evaluation of Association between Disc Bulge Migration, Lumbar Segmental Mobility, and Disc Degeneration in the Lumbar Spine Using Positional Magnetic Resonance Imaging

    PubMed Central

    Hu, Jonathan K.; Morishita, Yuichiro; Montgomery, Scott R.; Hymanson, Henry; Taghavi, Cyrus E.; Do, Duc; Wang, Jeff C.

    2011-01-01

    Degenerative disc disease and disc bulge in the lumbar spine are common sources of lower back pain. Little is known regarding disc bulge migration and lumbar segmental mobility as the lumbar spine moves from flexion to extension. In this study, 329 symptomatic (low back pain with or without neurological symptoms) patients with an average age of 43.5 years with varying degrees of disc degeneration were examined to characterize the kinematics of the lumbar intervertebral discs through flexion, neutral, and extension weight-bearing positions. In this population, disc bulge migration associated with dynamic motion of the lumbar spine significantly increased with increased grade of disk degeneration. Although no obvious trends relating the migration of disc bulge and angular segmental mobility were seen, translational segmental mobility tended to increase with disc bulge migration in all of the degenerative disc states. It appears that many factors, both static (intervertebral disc degeneration or disc height) and dynamic (lumbar segmental mobility), affect the mechanisms of lumbar disc bulge migration. PMID:24353937

  9. Activity-dependent release of tissue plasminogen activator from the dendritic spines of hippocampal neurons revealed by live-cell imaging.

    PubMed

    Lochner, Janis E; Honigman, Leah S; Grant, Wilmon F; Gessford, Sarah K; Hansen, Alexis B; Silverman, Michael A; Scalettar, Bethe A

    2006-05-01

    Tissue plasminogen activator (tPA) has been implicated in a variety of important cellular functions, including learning-related synaptic plasticity and potentiating N-methyl-D-aspartate (NMDA) receptor-dependent signaling. These findings suggest that tPA may localize to, and undergo activity-dependent secretion from, synapses; however, conclusive data supporting these hypotheses have remained elusive. To elucidate these issues, we studied the distribution, dynamics, and depolarization-induced secretion of tPA in hippocampal neurons, using fluorescent chimeras of tPA. We found that tPA resides in dense-core granules (DCGs) that traffic to postsynaptic dendritic spines and that can remain in spines for extended periods. We also found that depolarization induced by high potassium levels elicits a slow, partial exocytotic release of tPA from DCGs in spines that is dependent on extracellular Ca(+2) concentrations. This slow, partial release demonstrates that exocytosis occurs via a mechanism, such as fuse-pinch-linger, that allows partial release and reuse of DCG cargo and suggests a mechanism that hippocampal neurons may rely upon to avoid depleting tPA at active synapses. Our results also demonstrate release of tPA at a site that facilitates interaction with NMDA-type glutamate receptors, and they provide direct confirmation of fundamental hypotheses about tPA localization and release that bear on its neuromodulatory functions, for example, in learning and memory.

  10. Emergency department evaluation and treatment of cervical spine injuries.

    PubMed

    Kanwar, Rajdeep; Delasobera, Bronson E; Hudson, Korin; Frohna, William

    2015-05-01

    Most spinal cord injuries involve the cervical spine, highlighting the importance of recognition and proper management by emergency physicians. Initial cervical spine injury management should follow the ABCDE (airway, breathing, circulation, disability, exposure) procedure detailed by Advanced Trauma Life Support. NEXUS (National Emergency X-Radiography Utilization Study) criteria and Canadian C-spine Rule are clinical decision-making tools providing guidelines of when to obtain imaging. Computed tomography scans are the preferred initial imaging modality. Consider administering intravenous methylprednisolone after discussion with the neurosurgical consultant in patients who present with spinal cord injuries within 8 hours. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Activity-dependent dendritic spine neck changes are correlated with synaptic strength

    PubMed Central

    Araya, Roberto; Vogels, Tim P.; Yuste, Rafael

    2014-01-01

    Most excitatory inputs in the mammalian brain are made on dendritic spines, rather than on dendritic shafts. Spines compartmentalize calcium, and this biochemical isolation can underlie input-specific synaptic plasticity, providing a raison d’etre for spines. However, recent results indicate that the spine can experience a membrane potential different from that in the parent dendrite, as though the spine neck electrically isolated the spine. Here we use two-photon calcium imaging of mouse neocortical pyramidal neurons to analyze the correlation between the morphologies of spines activated under minimal synaptic stimulation and the excitatory postsynaptic potentials they generate. We find that excitatory postsynaptic potential amplitudes are inversely correlated with spine neck lengths. Furthermore, a spike timing-dependent plasticity protocol, in which two-photon glutamate uncaging over a spine is paired with postsynaptic spikes, produces rapid shrinkage of the spine neck and concomitant increases in the amplitude of the evoked spine potentials. Using numerical simulations, we explore the parameter regimes for the spine neck resistance and synaptic conductance changes necessary to explain our observations. Our data, directly correlating synaptic and morphological plasticity, imply that long-necked spines have small or negligible somatic voltage contributions, but that, upon synaptic stimulation paired with postsynaptic activity, they can shorten their necks and increase synaptic efficacy, thus changing the input/output gain of pyramidal neurons. PMID:24982196

  12. Point-of-Care Phalangeal Bone Mineral Density Measurement Can Reduce the Need of Dual-Energy X-Ray Absorptiometry Scanning in Danish Women at Risk of Fracture.

    PubMed

    Holmberg, Teresa; Bech, Mickael; Gram, Jeppe; Hermann, Anne Pernille; Rubin, Katrine Hass; Brixen, Kim

    2016-03-01

    Identifying persons with a high risk of osteoporotic fractures remains a challenge. DXA uptake in women with elevated risk of osteoporosis seems to be depending on distance to scanning facilities. This study aimed to investigate the ability of a small portable scanner in identifying women with reduced bone mineral density (BMD), and to define triage thresholds for pre-selection. Total hip and lumbar spine BMD was measured by dual-energy X-ray absorptiometry and phalangeal BMD by radiographic absorptiometry in 121 Danish women with intermediate or high 10-year fracture probability (aged 61-81 years). Correlation between the two methods was estimated using correlation coefficient (r) and Bland-Altman plots. A moderate correlation between phalangeal BMD versus total hip (r = 0.47) and lumbar spine (r = 0.51), and an AUC on 0.80 was found. The mean difference between phalangeal T score and total hip T score/lumbar spine T score was low, and ranged from -0.26 SD to -0.31 SD depending on site and reference database used for calculation of T scores, but, large variation was seen at an individual level. When applying a triage approach approx. one-third of all DXA scan could be avoided and only 6 % of women in the low-risk group would be false negatives.

  13. Ultrastructure of Dendritic Spines: Correlation Between Synaptic and Spine Morphologies

    PubMed Central

    Arellano, Jon I.; Benavides-Piccione, Ruth; DeFelipe, Javier; Yuste, Rafael

    2007-01-01

    Dendritic spines are critical elements of cortical circuits, since they establish most excitatory synapses. Recent studies have reported correlations between morphological and functional parameters of spines. Specifically, the spine head volume is correlated with the area of the postsynaptic density (PSD), the number of postsynaptic receptors and the ready-releasable pool of transmitter, whereas the length of the spine neck is proportional to the degree of biochemical and electrical isolation of the spine from its parent dendrite. Therefore, the morphology of a spine could determine its synaptic strength and learning rules. To better understand the natural variability of neocortical spine morphologies, we used a combination of gold-toned Golgi impregnations and serial thin-section electron microscopy and performed three-dimensional reconstructions of spines from layer 2/3 pyramidal cells from mouse visual cortex. We characterized the structure and synaptic features of 144 completed reconstructed spines, and analyzed their morphologies according to their positions. For all morphological parameters analyzed, spines exhibited a continuum of variability, without clearly distinguishable subtypes of spines or clear dependence of their morphologies on their distance to the soma. On average, the spine head volume was correlated strongly with PSD area and weakly with neck diameter, but not with neck length. The large morphological diversity suggests an equally large variability of synaptic strength and learning rules. PMID:18982124

  14. Thoracic spine x-ray

    MedlinePlus

    Vertebral radiography; X-ray - spine; Thoracic x-ray; Spine x-ray; Thoracic spine films; Back films ... The test is done in a hospital radiology department or in the health care provider's office. You will lie on the x-ray table in different positions. If the x-ray ...

  15. Sci-Fri AM: MRI and Diagnostic Imaging - 02: Quality Improvement: Diagnostic Reference Levels for Interior Health CT exams – L-Spine, Chest/Abdomen/pelvis, Abdomen/Pelvis, Head

    SciTech Connect

    Bjarnason, Thorarin

    Diagnostic Reference Levels are used to optimize patient dose and image quality in the clinical setting. It is assumed that the majority of exams are of diagnostic quality, or the radiologists would request protocol adjustments. By investigating the dose indicator distributions from all scanners, the upper DRL can be set to the 75th percentile of the distribution and a lower DRL can be set to the 10th percentile. Scanners using doses consistently outside the upper/lower DRL range can be adjusted accordingly. 11 CT scanners, all contributing to the American College of Radiology Dose Index Registry (ACR DIR) were used inmore » this study. Dose indicator data were compiled from the ACR DIR data and local DRLs established. Scanners with median doses outside the upper/lower DRL were followed-up with. Using effective dose and exam volumes, collective dose was determined before and after protocol adjustments to evaluate the effect of this quality improvement effort. The quality initiative is complete for L-spine and Chest/Abdomen/Pelvis exams and only initial surveys were completed for Head and Abdomen/Pelvis examsg. Median Scanner Dose reductions were 8.8 and 4.9 % for L-spine and Chest/Abdomen/Pelvis exams, respectively, resulting with collective dose reductions of 0.7 and 3.2 person•Sv/yr. Follow-up is ongoing for Abdomen/Pelvis and Head exams.« less

  16. Periscopic Spine Surgery.

    DTIC Science & Technology

    2000-02-01

    radiation medicine, the neurosurgery intensive care unit (ICU), and the pediatrics ICU [Geary 1999a]. The major procedures impacted are spine tumor...radiation medicine, and the pediatric intensive care unit . Hardware and software problems addressed included modifications of patient positioning...planning. Attempts have been made to link mechanical tissue properties to cellular interaction through electrical impedance [7] and to Hounsfield units

  17. Trunk density profile estimates from dual X-ray absorptiometry.

    PubMed

    Wicke, Jason; Dumas, Geneviève A; Costigan, Patrick A

    2008-01-01

    Accurate body segment parameters are necessary to estimate joint loads when using biomechanical models. Geometric methods can provide individualized data for these models but the accuracy of the geometric methods depends on accurate segment density estimates. The trunk, which is important in many biomechanical models, has the largest variability in density along its length. Therefore, the objectives of this study were to: (1) develop a new method for modeling trunk density profiles based on dual X-ray absorptiometry (DXA) and (2) develop a trunk density function for college-aged females and males that can be used in geometric methods. To this end, the density profiles of 25 females and 24 males were determined by combining the measurements from a photogrammetric method and DXA readings. A discrete Fourier transformation was then used to develop the density functions for each sex. The individual density and average density profiles compare well with the literature. There were distinct differences between the profiles of two of participants (one female and one male), and the average for their sex. It is believed that the variations in these two participants' density profiles were a result of the amount and distribution of fat they possessed. Further studies are needed to support this possibility. The new density functions eliminate the uniform density assumption associated with some geometric models thus providing more accurate trunk segment parameter estimates. In turn, more accurate moments and forces can be estimated for the kinetic analyses of certain human movements.

  18. Does Quantitative Tibial Ultrasound Predict Low Bone Mineral Density Defined by Dual Energy X-Ray Absorptiometry?

    PubMed Central

    Birtane, Murat; Ekuklu, Galip; Cermik, Fikret; Tuna, Filiz; Kokino, Siranus

    2008-01-01

    Purpose Efforts for the early detection of bone loss and subsequent fracture risk by quantitative ultrasound (QUS), which is a non-invasive, radiation free, and cheaper method, seem rational to reduce the management costs. We aimed in this study to assess the probable correlation of speed of sound (SOS) values obtained by QUS with bone mineral density (BMD) as measured by the gold standard method, dual energy X-ray absorptiometry (DEXA), and to investigate the diagnostic value of QUS to define low BMD. Materials and Methods One hundred twenty-two postmenopausal women having prior standard DEXA measurements were included in the study. Spine and proximal femur (neck, trochanter and Ward's triangle) BMD were assessed in a standard protocol by DEXA. The middle point of the right tibia was chosen for SOS measurement by tibial QUS. Results The SOS values were observed to be significantly higher in the normal BMD (t score > - 1) group at all measurement sites except for the lumbar region, when compared with the low BMD group (t score < - 1). SOS was negatively correlated with age (r = - 0.66) and month since menopause (r = - 0.57). The sensitivity, specificity, and positive and negative predictive values for QUS t score to diagnose low BMD did not seem to be satisfactory at either of the measurement sites. Conclusion Tibial SOS was correlated weakly with BMD values of femur and lumbar spine as measured by DEXA and its diagnostic value did not seem to be high for discriminating between normal and low BMD, at these sites. PMID:18581594

  19. Basic investigation of dual-energy x-ray absorptiometry for bone densitometry using computed radiography

    NASA Astrophysics Data System (ADS)

    Shimura, Kazuo; Nakajima, Nobuyoshi; Tanaka, Hiroshi; Ishida, Masamitsu; Kato, Hisatoyo

    1993-09-01

    Dual-energy X-ray absorptiometry (DXA) is one of the bone densitometry techniques to diagnose osteoporosis, and has been gradually getting popular due to its high degree of precision. However, DXA involves a time-consuming examination because of its pencil-beam scan, and the equipment is expensive. In this study, we examined a new bone densitometry technique (CR-DXA) utilizing an X-ray imaging system and Computed Radiography (CR) used for medical X-ray image diagnosis. High level of measurement precision and accuracy could be achieved by X-ray rube voltage/filter optimization and various nonuniformity corrections based on simulation and experiment. The phantom study using a bone mineral block showed precision of 0.83% c.v. (coefficient of variation), and accuracy of 0.01 g/cm2, suggesting that a practically equivalent degree of measurement precision and accuracy to that of the DXA approach is achieved. CR-DXA is considered to provide bone mineral densitometry to facilitate simple, quick and precise bone mineral density measurement.

  20. Hierarchical structures of cactus spines that aid in the directional movement of dew droplets

    PubMed Central

    Clement, R. M.; Gethin, D. T.; Kiernan, M.; Goral, T.; Griffiths, P.; Beynon, D.; Parker, A. R.

    2016-01-01

    Three species of cactus whose spines act as dew harvesters were chosen for this study: Copiapoa cinerea var. haseltoniana, Mammillaria columbiana subsp. yucatanensis and Parodia mammulosa and compared with Ferocactus wislizenii whose spines do not perform as dew harvesters. Time-lapse snapshots of C. cinerea showed movement of dew droplets from spine tips to their base, even against gravity. Spines emanating from one of the areoles of C. cinerea were submerged in water laced with fluorescent nanoparticles and this particular areole with its spines and a small area of stem was removed and imaged. These images clearly showed that fluorescent water had moved into the stem of the plant. Lines of vascular bundles radiating inwards from the surface areoles (from where the spines emanate) to the core of the stem were detected using magnetic resonance imaging, with the exception of F. wislizenii that does not harvest dew on its spines. Spine microstructures were examined using SEM images and surface roughness measurements (Ra and Rz) taken of the spines of C. cinerea. It was found that a roughness gradient created by tapered microgrooves existed that could potentially direct surface water from a spine tip to its base. This article is part of the themed issue ‘Bioinspired hierarchically structured surfaces for green science’. PMID:27354735

  1. Hierarchical structures of cactus spines that aid in the directional movement of dew droplets.

    PubMed

    Malik, F T; Clement, R M; Gethin, D T; Kiernan, M; Goral, T; Griffiths, P; Beynon, D; Parker, A R

    2016-08-06

    Three species of cactus whose spines act as dew harvesters were chosen for this study: Copiapoa cinerea var. haseltoniana, Mammillaria columbiana subsp. yucatanensis and Parodia mammulosa and compared with Ferocactus wislizenii whose spines do not perform as dew harvesters. Time-lapse snapshots of C. cinerea showed movement of dew droplets from spine tips to their base, even against gravity. Spines emanating from one of the areoles of C. cinerea were submerged in water laced with fluorescent nanoparticles and this particular areole with its spines and a small area of stem was removed and imaged. These images clearly showed that fluorescent water had moved into the stem of the plant. Lines of vascular bundles radiating inwards from the surface areoles (from where the spines emanate) to the core of the stem were detected using magnetic resonance imaging, with the exception of F. wislizenii that does not harvest dew on its spines. Spine microstructures were examined using SEM images and surface roughness measurements (Ra and Rz) taken of the spines of C. cinerea It was found that a roughness gradient created by tapered microgrooves existed that could potentially direct surface water from a spine tip to its base.This article is part of the themed issue 'Bioinspired hierarchically structured surfaces for green science'. © 2016 The Author(s).

  2. Controversies in "clearing" trauma to the cervical spine.

    PubMed

    Tins, Bernhard; Cassar-Pullicino, Victor

    2007-04-01

    Clearance of the traumatic cervical spine is a subject affecting most healthcare professionals dealing with trauma patients. There is a host of often contradictory literature making it hard for an interested reader to come to their own informed opinion based on the current evidence. This review aims to outline the relevant literature for the clearance of the traumatic cervical spine with the particular aim of highlighting the contradictions, controversies and unanswered questions still besetting this important subject. A brief, subjective opinion for a combined clinical and imaging protocol for clearance of the traumatic cervical spine is given.

  3. Acquired pathology of the pediatric spine and spinal cord.

    PubMed

    Palasis, Susan; Hayes, Laura L

    2015-09-01

    Pediatric spine pathology poses a diagnostic challenge for radiologists. Acquired spine pathology often yields nonspecific signs and symptoms in children, especially in the younger age groups, and diagnostic delay can carry significant morbidity. This review is focused on some of the more common diagnostic dilemmas we face when attempting to evaluate and diagnose acquired pediatric spine anomalies in daily practice. An understanding of some of the key differentiating features of these disease processes in conjunction with pertinent history, physical exam, and advanced imaging techniques can indicate the correct diagnosis.

  4. WE-AB-BRA-07: Operating Room Quality Assurance (ORQA) for Spine Surgery Using Known-Component 3D-2D Image Registration

    SciTech Connect

    Uneri, A; De Silva, T; Goerres, J

    Purpose: Intraoperative x-ray radiography/fluoroscopy is commonly used to qualitatively assess delivery of surgical devices (e.g., spine pedicle screws) but can fail to reliably detect suboptimal placement (e.g., breach of adjacent critical structures). We present a method wherein prior knowledge of the patient and surgical components is leveraged to match preoperative CT and intraoperative radiographs for quantitative assessment of 3D pose. The method presents a new means of operating room quantitative quality assurance (ORQA) that could improve quality and safety, and reduce the frequency of revision surgeries. Methods: The algorithm (known-component registration, KC-Reg) uses patient-specific preoperative CT and parametrically defined surgicalmore » component models within a robust 3D-2D registration method to iteratively optimize gradient similarity using the covariance matrix adaptation evolution strategy. Advances from previous work address key challenges to clinical translation: i) absolving the need for offline geometric calibration of the C-arm; and ii) solving multiple component bodies simultaneously, thereby allowing QA in a single step (e.g., spinal construct with 4–20 screws), rather than sequential QA of each component. Performance was tested in a spine phantom with 10 pedicle screws, and first results from clinical studies are reported. Results: Phantom experiments demonstrated median target registration error (TRE) of (1.0±0.3) mm at the screw tip and (0.7°±0.4°) in angulation. The simultaneous multi-body registration approach improved TRE from the previous (sequential) method by 42%, reduced outliers, and fits into the natural workflow. Initial application of KC-Reg in clinical data shows TRE of (2.5±4.5) mm and (4.7°±0.5°). Conclusion: The KC-Reg algorithm offers a potentially valuable method for quantitative QA of the surgical product, using radiographic systems that are already within the surgical arsenal. For spine surgery, the

  5. The morphometric study of l3-L4 and L4-L5 lumbar spine in Asian population using magnetic resonance imaging: feasibility analysis for transpsoas lumbar interbody fusion.

    PubMed

    Yusof, Mohd Imran; Nadarajan, Eswaran; Abdullah, Mohd Shafie

    2014-06-15

    Cross-sectional study on the measurement of relevant magnetic resonance imaging parameters in 100 patients presented for lumbar spine assessment. To determine anatomical position of lumbar plexus and major blood vessels in relation to vertebral body and anterior edge of psoas muscle at L3-L4 and L4-L5 and to define the safe working zone for transpsoas approach for lumbar fusion. Lateral transpsoas lumbar interbody fusion has been shown to be safe and provides alternative for lumbar fusion. However, proximity of neurovascular structures may not allow a safe passage for this procedure in the Asian population. Relevant parameters were measured from axial magnetic resonance images and analyzed, including the psoas muscle and vertebrae endplate diameters, lumbar plexus and psoas muscle distance, lumbar plexus and vertebra body distance, and vena cava to the anterior vertebrae body diameters. The mean anteroposterior diameters of the right and left psoas muscle ranged from 44.0 to 58.6 mm and 44.8 to 54.0 mm, respectively. The mean anteroposterior diameters of vertebra endplate of L3, L4, and L5 were 38.2 mm, 39.3 mm, and 41.4 mm, respectively. The mean distance of posterior border of vena cava from the vertebra body was 4.5 mm at L3-L4 and 14.1 mm at L4-L5. L3-L4 fusion is feasible at both sides in both sexes; however, at L4-L5 level, the procedure is feasible only on the left side. The safe working zone for transpsoas approach to lumbar spine is significantly narrower at L4-L5 in both sexes. Anterior edge of psoas muscle can be used as a reliable guide to locate lumbar plexus within psoas muscle. N/A.

  6. Visualization of scoliotic spine using ultrasound-accessible skeletal landmarks

    NASA Astrophysics Data System (ADS)

    Church, Ben; Lasso, Andras; Schlenger, Christopher; Borschneck, Daniel P.; Mousavi, Parvin; Fichtinger, Gabor; Ungi, Tamas

    2017-03-01

    PURPOSE: Ultrasound imaging is an attractive alternative to X-ray for scoliosis diagnosis and monitoring due to its safety and inexpensiveness. The transverse processes as skeletal landmarks are accessible by means of ultrasound and are sufficient for quantifying scoliosis, but do not provide an informative visualization of the spine. METHODS: We created a method for visualization of the scoliotic spine using a 3D transform field, resulting from thin-spline interpolation of a landmark-based registration between the transverse processes that we localized in both the patient's ultrasound and an average healthy spine model. Additional anchor points were computationally generated to control the thin-spline interpolation, in order to gain a transform field that accurately represents the deformation of the patient's spine. The transform field is applied to the average spine model, resulting in a 3D surface model depicting the patient's spine. We applied ground truth CT from pediatric scoliosis patients in which we reconstructed the bone surface and localized the transverse processes. We warped the average spine model and analyzed the match between the patient's bone surface and the warped spine. RESULTS: Visual inspection revealed accurate rendering of the scoliotic spine. Notable misalignments occurred mainly in the anterior-posterior direction, and at the first and last vertebrae, which is immaterial for scoliosis quantification. The average Hausdorff distance computed for 4 patients was 2.6 mm. CONCLUSIONS: We achieved qualitatively accurate and intuitive visualization to depict the 3D deformation of the patient's spine when compared to ground truth CT.

  7. The continued burden of spine fractures after motor vehicle crashes.

    PubMed

    Wang, Marjorie C; Pintar, Frank; Yoganandan, Narayan; Maiman, Dennis J

    2009-02-01

    occurrence of spine fractures increased from 1994 to 2002 despite concomitant increases in seat belt and air bag use. However, the occurrence of severe spine fractures did not increase over the study period. The use of both seat belt and air bag is protective against spine fractures. Although the overall increased occurrence of spine fractures may appear contrary to the increased use of seat belts and air bags in general, it is possible that improved imaging technology may be associated with an increase in the diagnosis of relatively minor fractures. However, given the significant protective effects of both seat belt and air bag use against spine fractures, resources should continue to be dedicated toward increasing their use to mitigate the effects of MVCs.

  8. Bone density of the radius, spine, and proximal femur in osteoporosis

    SciTech Connect

    Mazess, R.B.; Barden, H.; Ettinger, M.

    1988-02-01

    Bone mineral density (BMD) was measured in 140 normal young women (aged 20 to 39 years) and in 423 consecutive women over age 40 referred for evaluation of osteoporosis. Lumbar spine and proximal femur BMD was measured using dual-photon absorptiometry (/sup 153/Gd), whereas the radius shaft measurement used single-photon absorptiometry (/sup 125/I). There were 324 older women with no fractures, of which 278 aged 60 to 80 years served as age-matched controls. There were 99 women with fractures including 32 with vertebral and 22 with hip fractures. Subsequently, another 25 women with hip fractures had BMD measured in another laboratory;more » their mean BMD was within 2% of that of the original series. The mean age in both the nonfracture and fracture groups was 70 +/- 5 years. The BMD in the age-matched controls was 20% to 25% below that of normal young women for the radius, spine, and femur, but the Ward's triangle region of the femur showed even greater loss (35%). The mean BMD at all sites in the crush fracture cases was about 10% to 15% below that of age-matched controls. Spinal abnormality was best discriminated by spine and femoral measurements (Z score about 0.9). In women with hip fractures, the BMD was 10% below that of age-matched controls for the radius and the spine, and the BMD for the femoral sites was about 25% to 30% below that of age-matched control (Z score about 1.6). Femoral densities gave the best discrimination of hip fracture cases and even reflected spinal osteopenia. In contrast, neither the spine nor the radius reflected the full extent of femoral osteopenia in hip fracture.« less

  9. The top 100 classic papers in lumbar spine surgery.

    PubMed

    Steinberger, Jeremy; Skovrlj, Branko; Caridi, John M; Cho, Samuel K

    2015-05-15

    Bibliometric review of the literature. To analyze and quantify the most frequently cited papers in lumbar spine surgery and to measure their impact on the entire lumbar spine literature. Lumbar spine surgery is a dynamic and complex field. Basic science and clinical research remain paramount in understanding and advancing the field. While new literature is published at increasing rates, few studies make long-lasting impacts. The Thomson Reuters Web of Knowledge was searched for citations of all papers relevant to lumbar spine surgery. The number of citations, authorship, year of publication, journal of publication, country of publication, and institution were recorded for each paper. The most cited paper was found to be the classic paper from 1990 by Boden et al that described magnetic resonance imaging findings in individuals without back pain, sciatica, and neurogenic claudication showing that spinal stenosis and herniated discs can be incidentally found when scanning patients. The second most cited study similarly showed that asymptomatic patients who underwent lumbar spine magnetic resonance imaging frequently had lumbar pathology. The third most cited paper was the 2000 publication of Fairbank and Pynsent reviewing the Oswestry Disability Index, the outcome-measure questionnaire most commonly used to evaluate low back pain. The majority of the papers originate in the United States (n=58), and most were published in Spine (n=63). Most papers were published in the 1990s (n=49), and the 3 most common topics were low back pain, biomechanics, and disc degeneration. This report identifies the top 100 papers in lumbar spine surgery and acknowledges those individuals who have contributed the most to the advancement of the study of the lumbar spine and the body of knowledge used to guide evidence-based clinical decision making in lumbar spine surgery today. 3.

  10. Height adjustment in assessing dual energy x-ray absorptiometry measurements of bone mass and density in children.

    PubMed

    Zemel, Babette S; Leonard, Mary B; Kelly, Andrea; Lappe, Joan M; Gilsanz, Vicente; Oberfield, Sharon; Mahboubi, Soroosh; Shepherd, John A; Hangartner, Thomas N; Frederick, Margaret M; Winer, Karen K; Kalkwarf, Heidi J

    2010-03-01

    In children, bone mineral content (BMC) and bone mineral density (BMD) measurements by dual-energy x-ray absorptiometry (DXA) are affected by height status. No consensus exists on how to adjust BMC or BMD (BMC/BMD) measurements for short or tall stature. The aim of this study was to compare various methods to adjust BMC/BMD for height in healthy children. Data from the Bone Mineral Density in Childhood Study (BMDCS) were used to develop adjustment methods that were validated using an independent cross-sectional sample of healthy children from the Reference Data Project (RDP). We conducted the study in five clinical centers in the United States. We included 1546 BMDCS and 650 RDP participants (7 to 17 yr of age, 50% female). No interventions were used. We measured spine and whole body (WB) BMC and BMD Z-scores for age (BMC/BMD(age)), height age (BMC/BMD(height age)), height (BMC(height)), bone mineral apparent density (BMAD(age)), and height-for-age Z-score (HAZ) (BMC/BMD(haz)). Spine and WB BMC/BMD(age)Z and BMAD(age)Z were positively (P < 0.005; r = 0.11 to 0.64) associated with HAZ. Spine BMD(haz) and BMC(haz)Z were not associated with HAZ; WB BMC(haz)Z was modestly associated with HAZ (r = 0.14; P = 0.0003). All other adjustment methods were negatively associated with HAZ (P < 0.005; r = -0.20 to -0.34). The deviation between adjusted and BMC/BMD(age) Z-scores was associated with age for most measures (P < 0.005) except for BMC/BMD(haz). Most methods to adjust BMC/BMD Z-scores for height were biased by age and/or HAZ. Adjustments using HAZ were least biased relative to HAZ and age and can be used to evaluate the effect of short or tall stature on BMC/BMD Z-scores.

  11. Ageing and degradation determines failure mode on sea urchin spines.

    PubMed

    Merino, Monica; Vicente, Erika; Gonzales, Karen N; Torres, Fernando G

    2017-09-01

    Sea urchin spines are an example of a hard natural composite with mineral and organic phases. The role of the organic phase in the response to mechanical stress was assessed by promoting the degradation of such spines by exposing them to ageing and ultraviolet (UV) irradiation. Thermal and structural characterization of the irradiated samples show that this UV irradiation treatment promotes degradation of the organic and inorganic phase of spines. Uniaxial compression tests carried out on aged and UV irradiated samples showed that both treatments affected the mechanical properties of the spines. Scanning electron microscopy (SEM) images of failed specimens were used to analyze the failure mechanisms of the compressed spines. The analysis of the fracture surfaces showed that the failure mechanisms of spines were modified as a consequence of UV irradiation, leading in the last case to mostly brittle fracture surfaces. We suggest that the proteins responsible for the formation of calcite also determine the mechanical properties and the failure mode of spines. This system can be used as a model for the study of the failure modes of other natural and synthetic hard composites. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Automated quasi-3D spine curvature quantification and classification

    NASA Astrophysics Data System (ADS)

    Khilari, Rupal; Puchin, Juris; Okada, Kazunori

    2018-02-01

    Scoliosis is a highly prevalent spine deformity that has traditionally been diagnosed through measurement of the Cobb angle on radiographs. More recent technology such as the commercial EOS imaging system, although more accurate, also require manual intervention for selecting the extremes of the vertebrae forming the Cobb angle. This results in a high degree of inter and intra observer error in determining the extent of spine deformity. Our primary focus is to eliminate the need for manual intervention by robustly quantifying the curvature of the spine in three dimensions, making it consistent across multiple observers. Given the vertebrae centroids, the proposed Vertebrae Sequence Angle (VSA) estimation and segmentation algorithm finds the largest angle between consecutive pairs of centroids within multiple inflection points on the curve. To exploit existing clinical diagnostic standards, the algorithm uses a quasi-3-dimensional approach considering the curvature in the coronal and sagittal projection planes of the spine. Experiments were performed with manuallyannotated ground-truth classification of publicly available, centroid-annotated CT spine datasets. This was compared with the results obtained from manual Cobb and Centroid angle estimation methods. Using the VSA, we then automatically classify the occurrence and the severity of spine curvature based on Lenke's classification for idiopathic scoliosis. We observe that the results appear promising with a scoliotic angle lying within +/- 9° of the Cobb and Centroid angle, and vertebrae positions differing by at the most one position. Our system also resulted in perfect classification of scoliotic from healthy spines with our dataset with six cases.

  13. Delayed stabilization of dendritic spines in fragile X mice.

    PubMed

    Cruz-Martín, Alberto; Crespo, Michelle; Portera-Cailliau, Carlos

    2010-06-09

    Fragile X syndrome (FXS) causes mental impairment and autism through transcriptional silencing of the Fmr1 gene, resulting in the loss of the RNA-binding protein fragile X mental retardation protein (FMRP). Cortical pyramidal neurons in affected individuals and Fmr1 knock-out (KO) mice have an increased density of dendritic spines. The mutant mice also show defects in synaptic and experience-dependent circuit plasticity, which are known to be mediated in part by dendritic spine dynamics. We used in vivo time-lapse imaging with two-photon microscopy through cranial windows in male and female neonatal mice to test the hypothesis that dynamics of dendritic protrusions are altered in KO mice during early postnatal development. We find that layer 2/3 neurons from wild-type mice exhibit a rapid decrease in dendritic spine dynamics during the first 2 postnatal weeks, as immature filopodia are replaced by mushroom spines. In contrast, KO mice show a developmental delay in the downregulation of spine turnover and in the transition from immature to mature spine subtypes. Blockade of metabotropic glutamate receptor (mGluR) signaling, which reverses some adult phenotypes of KO mice, accentuated this immature protrusion phenotype in KO mice. Thus, absence of FMRP delays spine stabilization and dysregulated mGluR signaling in FXS may partially normalize this early synaptic defect.

  14. Heritability of Thoracic Spine Curvature and Genetic Correlations With Other Spine Traits: The Framingham Study

    PubMed Central

    Yau, Michelle S; Demissie, Serkalem; Zhou, Yanhua; Anderson, Dennis E; Lorbergs, Amanda L; Kiel, Douglas P; Allaire, Brett T; Yang, Laiji; Cupples, L Adrienne; Travison, Thomas G; Bouxsein, Mary L; Karasik, David; Samelson, Elizabeth J

    2017-01-01

    Hyperkyphosis is a common spinal disorder in older adults, characterized by excessive forward curvature of the thoracic spine and adverse health outcomes. The etiology of hyperkyphosis has not been firmly established, but may be related to changes that occur with aging in the vertebrae, discs, joints, and muscles, which function as a unit to support the spine. Determining the contribution of genetics to thoracic spine curvature and the degree of genetic sharing among co-occurring measures of spine health may provide insight into the etiology of hyperkyphosis. The purpose of our study was to estimate heritability of thoracic spine curvature using T4–T12 kyphosis (Cobb) angle and genetic correlations between thoracic spine curvature and vertebral fracture, intervertebral disc height narrowing, facet joint osteoarthritis (OA), lumbar spine volumetric bone mineral density (vBMD), and paraspinal muscle area and density, which were all assessed from computed tomography (CT) images. Participants included 2063 women and men in the second and third generation offspring of the original cohort of the Framingham Study. Heritability of kyphosis angle, adjusted for age, sex, and weight, was 54% (95% confidence interval [CI], 43% to 64%). We found moderate genetic correlations between kyphosis angle and paraspinal muscle area ( ρ^G, −0.46; 95% CI, −0.67 to −0.26), vertebral fracture ( ρ^G, 0.39; 95% CI, 0.18 to 0.61), vBMD ( ρ^G,−0.23; 95% CI, −0.41 to −0.04), and paraspinal muscle density ( ρ^G,−0.22; 95% CI, −0.48 to 0.03). Genetic correlations between kyphosis angle and disc height narrowing ( ρ^G, 0.17; 95% CI, −0.05 to 0.38) and facet joint OA ( ρ^G, 0.05; 95% CI, −0.15 to 0.24) were low. Thoracic spine curvature may be heritable and share genetic factors with other age-related spine traits including trunk muscle size, vertebral fracture, and bone mineral density. PMID:27455046

  15. Electrical and Ca2+ signaling in dendritic spines of substantia nigra dopaminergic neurons

    PubMed Central

    Hage, Travis A; Sun, Yujie; Khaliq, Zayd M

    2016-01-01

    Little is known about the density and function of dendritic spines on midbrain dopamine neurons, or the relative contribution of spine and shaft synapses to excitability. Using Ca2+ imaging, glutamate uncaging, fluorescence recovery after photobleaching and transgenic mice expressing labeled PSD-95, we comparatively analyzed electrical and Ca2+ signaling in spines and shaft synapses of dopamine neurons. Dendritic spines were present on dopaminergic neurons at low densities in live and fixed tissue. Uncaging-evoked potential amplitudes correlated inversely with spine length but positively with the presence of PSD-95. Spine Ca2+ signals were less sensitive to hyperpolarization than shaft synapses, suggesting amplification of spine head voltages. Lastly, activating spines during pacemaking, we observed an unexpected enhancement of spine Ca2+ midway throughout the spike cycle, likely involving recruitment of NMDA receptors and voltage-gated conductances. These results demonstrate functionality of spines in dopamine neurons and reveal a novel modulation of spine Ca2+ signaling during pacemaking. DOI: http://dx.doi.org/10.7554/eLife.13905.001 PMID:27163179

  16. The spread of Ras activity triggered by activation of a single dendritic spine.

    PubMed

    Harvey, Christopher D; Yasuda, Ryohei; Zhong, Haining; Svoboda, Karel

    2008-07-04

    In neurons, individual dendritic spines isolate N-methyl-d-aspartate (NMDA) receptor-mediated calcium ion (Ca2+) accumulations from the dendrite and other spines. However, the extent to which spines compartmentalize signaling events downstream of Ca2+ influx is not known. We combined two-photon fluorescence lifetime imaging with two-photon glutamate uncaging to image the activity of the small guanosine triphosphatase Ras after NMDA receptor activation at individual spines. Induction of long-term potentiation (LTP) triggered robust Ca2+-dependent Ras activation in single spines that decayed in approximately 5 minutes. Ras activity spread over approximately 10 micrometers of dendrite and invaded neighboring spines by diffusion. The spread of Ras-dependent signaling was necessary for the local regulation of the threshold for LTP induction. Thus, Ca2+-dependent synaptic signals can spread to couple multiple synapses on short stretches of dendrite.

  17. Morphometric analysis of the developing pediatric cervical spine.

    PubMed

    Johnson, Kyle T; Al-Holou, Wajd N; Anderson, Richard C E; Wilson, Thomas J; Karnati, Tejas; Ibrahim, Mohannad; Garton, Hugh J L; Maher, Cormac O

    2016-09-01

    OBJECTIVE Our understanding of pediatric cervical spine development remains incomplete. The purpose of this analysis was to quantitatively define cervical spine growth in a population of children with normal CT scans. METHODS A total of 1458 children older than 1 year and younger than 18 years of age who had undergone a cervical spine CT scan at the authors' institution were identified. Subjects were separated by sex and age (in years) into 34 groups. Following this assignment, subjects within each group were randomly selected for inclusion until a target of 15 subjects in each group had been measured. Linear measurements were performed on the midsagittal image of the cervical spine. Twenty-three unique measurements were obtained for each subject. RESULTS Data showed that normal vertical growth of the pediatric cervical spine continues up to 18 years of age in boys and 14 years of age in girls. Approximately 75% of the vertical growth occurs throughout the subaxial spine and 25% occurs across the craniovertebral region. The C-2 body is the largest single-segment contributor to vertical growth, but the subaxial vertebral bodies and disc spaces also contribute. Overall vertical growth of the cervical spine throughout childhood is dependent on individual vertebral body growth as well as vertical growth of the disc spaces. The majority of spinal canal diameter growth occurs by 4 years of age. CONCLUSIONS The authors' morphometric analyses establish parameters for normal pediatric cervical spine growth up to 18 years of age. These data should be considered when evaluating children for potential surgical intervention and provide a basis of comparison for studies investigating the effects of cervical spine instrumentation and fusion on subsequent growth.

  18. PTEN knockdown alters dendritic spine/protrusion morphology, not density

    PubMed Central

    Haws, Michael E.; Jaramillo, Thomas C.; Espinosa-Becerra, Felipe; Widman, Allie; Stuber, Garret D.; Sparta, Dennis R.; Tye, Kay M.; Russo, Scott J.; Parada, Luis F.; Kaplitt, Michael; Bonci, Antonello; Powell, Craig M.

    2014-01-01

    Mutations in phosphatase and tensin homolog deleted on chromosome ten (PTEN) are implicated in neuropsychiatric disorders including autism. Previous studies report that PTEN knockdown in neurons in vivo leads to increased spine density and synaptic activity. To better characterize synaptic changes in neurons lacking PTEN, we examined the effects of shRNA knockdown of PTEN in basolateral amygdala neurons on synaptic spine density and morphology using fluorescent dye confocal imaging. Contrary to previous studies in dentate gyrus, we find that knockdown of PTEN in basolateral amygdala leads to a significant decrease in total spine density in distal dendrites. Curiously, this decreased spine density is associated with increased miniature excitatory post-synaptic current frequency and amplitude, suggesting an increase in number and function of mature spines. These seemingly contradictory findings were reconciled by spine morphology analysis demonstrating increased mushroom spine density and size with correspondingly decreased thin protrusion density at more distal segments. The same analysis of PTEN conditional deletion in dentate gyrus demonstrated that loss of PTEN does not significantly alter total density of dendritic protrusions in the dentate gyrus, but does decrease thin protrusion density and increases density of more mature mushroom spines. These findings suggest that, contrary to previous reports, PTEN knockdown may not induce de novo spinogenesis, but instead may increase synaptic activity by inducing morphological and functional maturation of spines. Furthermore, behavioral analysis of basolateral amygdala PTEN knockdown suggests that these changes limited only to the basolateral amygdala complex may not be sufficient to induce increased anxiety-related behaviors. PMID:24264880

  19. Spine oncology: Daedalus, Theseus, and the Minotaur.

    PubMed

    Donthineni, Rakesh; Ofluoglu, Onder

    2009-01-01

    Over the past three decades, progress has been dramatic in the management of spine tumors. For example, advanced imaging technologies made available at manageable costs have lowered the threshold for scanning. CT, MRI, and PET imaging modalities have greatly enhanced the ability of the surgeon to accurately delineate the extension of the lesion within the bone, the soft tissue, and the spinal canal. Such enhancements have led to great leaps forward in preoperative planning and postoperative evaluation, including improved reconstruction options are resulting in improved outcomes. This article introduces the theme of this volume.

  20. Impact of beverage consumption, age, and site dependency on dual energy X-ray absorptiometry (DEXA) measurements in perimenopausal women: a prospective study.

    PubMed

    Lo, Huan-Chu; Kuo, Duen-Pang; Chen, Yen-Lin

    2017-08-01

    The aim of this study was to determine the best site for bone mineral density (BMD) measurements based on T -scores, age, and beverage consumption. In this prospective study, 271 women stratified by age (average age: 61.9 years) underwent dual energy X-ray absorptiometry (DEXA) scanning of their lumbar spine, hips, and forearms. Osteoporosis was defined as a BMD of 2.5 standard deviations or more below the mean peak bone mass based on a reference population of adult women (translated as a T -score ≤ -2.5), as measured by DEXA. Participants were also evaluated regarding alcohol and caffeine consumption by a semiquantitative questionnaire. A significant discrepancy was observed in the classification of osteoporosis at different locations, with hip and forearm showing the best correlation (Pearson's r = 0.627, p < 0.001). In addition, for participants over 50 years of age, hip and forearm showed the best correlation. Significant correlations were also noted between forearm T -scores and caffeine consumed and, to a lesser extent, the level of alcohol consumption. In the group ≤ 50 years of age, lumbar spine and forearm T -scores were only associated with alcohol consumption. In the group over 50 years of age, hip and forearm T -scores were only associated with caffeine consumption. Bone mineral density measurements at the hip and forearm correlated with caffeine consumption in elderly Taiwanese women. This is an important finding since age and caffeine consumption are known risk factors for osteoporosis.

  1. Quantifying the quality of medical x-ray images: An evaluation based on normal anatomy for lumbar spine and chest radiography

    NASA Astrophysics Data System (ADS)

    Tingberg, Anders Martin

    Optimisation in diagnostic radiology requires accurate methods for determination of patient absorbed dose and clinical image quality. Simple methods for evaluation of clinical image quality are at present scarce and this project aims at developing such methods. Two methods are used and further developed; fulfillment of image criteria (IC) and visual grading analysis (VGA). Clinical image quality descriptors are defined based on these two methods: image criteria score (ICS) and visual grading analysis score (VGAS), respectively. For both methods the basis is the Image Criteria of the ``European Guidelines on Quality Criteria for Diagnostic Radiographic Images''. Both methods have proved to be useful for evaluation of clinical image quality. The two methods complement each other: IC is an absolute method, which means that the quality of images of different patients and produced with different radiographic techniques can be compared with each other. The separating power of IC is, however, weaker than that of VGA. VGA is the best method for comparing images produced with different radiographic techniques and has strong separating power, but the results are relative, since the quality of an image is compared to the quality of a reference image. The usefulness of the two methods has been verified by comparing the results from both of them with results from a generally accepted method for evaluation of clinical image quality, receiver operating characteristics (ROC). The results of the comparison between the two methods based on visibility of anatomical structures and the method based on detection of pathological structures (free-response forced error) indicate that the former two methods can be used for evaluation of clinical image quality as efficiently as the method based on ROC. More studies are, however, needed for us to be able to draw a general conclusion, including studies of other organs, using other radiographic techniques, etc. The results of the experimental

  2. Spine problems in young athletes.

    PubMed

    Sucato, Daniel J; Micheli, Lyle J; Estes, A Reed; Tolo, Vernon T

    2012-01-01

    As the number of young people involved in sports activities increases, acute and chronic back pain has become more common. With a careful medical history and physical examination, along with the judicious use of imaging modalities, the causes of back pain can be correctly diagnosed and treated so that young athletes can quickly return to sports participation. Although most back pain in these young patients is muscular in origin, findings that should trigger increased concern include night pain, marked hamstring tightness, pain with lumbar spine hyperextension, or any neurologic finding. When recently developed vague back pain is present, a delay in radiographic imaging is warranted. With new back pain after trauma, AP and lateral radiographs of the symptomatic spinal area are indicated. CT, bone scans, and MRI should be reserved for special circumstances. Spondylolysis is the most common bony cause of back pain in young athletes. Spondylolysis can be treated with activity limitation, a specific exercise program, a thoracolumbar orthosis, and/or surgery. Treatment should be based on the amount of pain as well as the desire of the young athlete to continue in the sports activity that caused the pain. Other significant causes of back pain that require more extensive treatment in these young athletes include spondylolisthesis, lumbar disk disorders, and sacral stress fractures. It is anticipated that nearly all young athletes can return to sports activity after successful treatment. Even if surgical treatment is needed, return to all sports is expected, with the occasional exception of collision sports.

  3. Development of Ultrasound to Measure In-Vivo Dynamic Cervical Spine Intervertebral Disc Mechanics

    DTIC Science & Technology

    2016-01-01

    Award Number: W81XWH-13-1-0050 TITLE: Development of Ultrasound to Measure In-vivo Dynamic Cervical Spine Intervertebral Disc Mechanics PRINCIPAL...CONTRACT NUMBER W81XWH-13-1-0050 Development of Ultrasound to Measure In-vivo Dynamic Cervical Spine Intervertebral Disc Mechanics 5b. GRANT NUMBER 5c...elasticity during compression or tension. As a portable, low cost imaging modality, the dual ultrasound system quantified cervical spine IVD displacement and

  4. Electrical Advantages of Dendritic Spines

    PubMed Central

    Gulledge, Allan T.; Carnevale, Nicholas T.; Stuart, Greg J.

    2012-01-01

    Many neurons receive excitatory glutamatergic input almost exclusively onto dendritic spines. In the absence of spines, the amplitudes and kinetics of excitatory postsynaptic potentials (EPSPs) at the site of synaptic input are highly variable and depend on dendritic location. We hypothesized that dendritic spines standardize the local geometry at the site of synaptic input, thereby reducing location-dependent variability of local EPSP properties. We tested this hypothesis using computational models of simplified and morphologically realistic spiny neurons that allow direct comparison of EPSPs generated on spine heads with EPSPs generated on dendritic shafts at the same dendritic locations. In all morphologies tested, spines greatly reduced location-dependent variability of local EPSP amplitude and kinetics, while having minimal impact on EPSPs measured at the soma. Spine-dependent standardization of local EPSP properties persisted across a range of physiologically relevant spine neck resistances, and in models with variable neck resistances. By reducing the variability of local EPSPs, spines standardized synaptic activation of NMDA receptors and voltage-gated calcium channels. Furthermore, spines enhanced activation of NMDA receptors and facilitated the generation of NMDA spikes and axonal action potentials in response to synaptic input. Finally, we show that dynamic regulation of spine neck geometry can preserve local EPSP properties following plasticity-driven changes in synaptic strength, but is inefficient in modifying the amplitude of EPSPs in other cellular compartments. These observations suggest that one function of dendritic spines is to standardize local EPSP properties throughout the dendritic tree, thereby allowing neurons to use similar voltage-sensitive postsynaptic mechanisms at all dendritic locations. PMID:22532875

  5. Yield of computed tomography of the cervical spine in cases of simple assault.

    PubMed

    Uriell, Matthew L; Allen, Jason W; Lovasik, Brendan P; Benayoun, Marc D; Spandorfer, Robert M; Holder, Chad A

    2017-01-01

    Computed tomography (CT) of the cervical spine (C-spine) is routinely ordered for low-impact, non-penetrating or "simple" assault at our institution and others. Common clinical decision tools for C-spine imaging in the setting of trauma include the National Emergency X-Radiography Utilization Study (NEXUS) and the Canadian Cervical Spine Rule for Radiography (CCR). While NEXUS and CCR have served to decrease the amount of unnecessary imaging of the C-spine, overutilization of CT is still of concern. A retrospective, cross-sectional study was performed of the electronic medical record (EMR) database at an urban, Level I Trauma Center over a 6-month period for patients receiving a C-spine CT. The primary outcome of interest was prevalence of cervical spine fracture. Secondary outcomes of interest included appropriateness of C-spine imaging after retrospective application of NEXUS and CCR. The hypothesis was that fracture rates within this patient population would be extremely low. No C-spine fractures were identified in the 460 patients who met inclusion criteria. Approximately 29% of patients did not warrant imaging by CCR, and 25% by NEXUS. Of note, approximately 44% of patients were indeterminate for whether imaging was warranted by CCR, with the most common reason being lack of assessment for active neck rotation. Cervical spine CT is overutilized in the setting of simple assault, despite established clinical decision rules. With no fractures identified regardless of other factors, the likelihood that a CT of the cervical spine will identify clinically significant findings in the setting of "simple" assault is extremely low, approaching zero. At minimum, adherence to CCR and NEXUS within this patient population would serve to reduce both imaging costs and population radiation dose exposure. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Analysis of dendritic spine morphology in cultured CNS neurons.

    PubMed

    Srivastava, Deepak P; Woolfrey, Kevin M; Penzes, Peter

    2011-07-13

    Dendritic spines are the sites of the majority of excitatory connections within the brain, and form the post-synaptic compartment of synapses. These structures are rich in actin and have been shown to be highly dynamic. In response to classical Hebbian plasticity as well as neuromodulatory signals, dendritic spines can change shape and number, which is thought to be critical for the refinement of neural circuits and the processing and storage of information within the brain. Within dendritic spines, a complex network of proteins link extracellular signals with the actin cyctoskeleton allowing for control of dendritic spine morphology and number. Neuropathological studies have demonstrated that a number of disease states, ranging from schizophrenia to autism spectrum disorders, display abnormal dendritic spine morphology or numbers. Moreover, recent genetic studies have identified mutations in numerous genes that encode synaptic proteins, leading to suggestions that these proteins may contribute to aberrant spine plasticity that, in part, underlie the pathophysiology of these disorders. In order to study the potential role of these proteins in controlling dendritic spine morphologies/number, the use of cultured cortical neurons offers several advantages. Firstly, this system allows for high-resolution imaging of dendritic spines in fixed cells as well as time-lapse imaging of live cells. Secondly, this in vitro system allows for easy manipulation of protein function by expression of mutant proteins, knockdown by shRNA constructs, or pharmacological treatments. These techniques allow researchers to begin to dissect the role of disease-associated proteins and to predict how mutations of these proteins may function in vivo.

  7. Lateral spine densitometry in obese women.

    PubMed

    Brooks, E R; Heltz, D; Wozniak, P; Partington, C; Lovejoy, J C

    1998-08-01

    The lateral (LAT) spine scan has been suggested as a more sensitive measure than posterior-anterior (PA) scanning for assessing age-related bone loss in normal-weight postmenopausal women. The measurement error of PA and LAT bone mineral density (BMD) using dual energy X-ray absorptiometry (DXA) has also been shown to rise with incremental increases in fat and from large variance in fat thickness, respectively. The purpose of this cross-sectional study was to determine specific affects of obesity on paired PA and LAT lumbar (L2-L4) BMD and Z score (BMD of patient versus age-matched reference data-base) correlation in 30 obese postmenopausal women (mean BMI +/- SD = 33.3 +/- 4.06). The mean PA and LAT BMD +/- SD were 0.946 +/- 0.123 and 0.749 +/- 0.134, respectively. The mean PA and LAT Z scores were -0.17 +/- 1.15 and 0.80 +/- 1.7. The correlation between PA and LAT BMD was significantly lower (r = 0.55; P < 0.05) than previously reported, and PA and LAT Z score correlation was (r = 0.57; P = 0.0016). After adjusting for body mass index (BMI), percent body fat, fat mass, and truncal fat by DXA, waist:hip ratio (WHR) and visceral and subcutaneous abdominal fat by computerized axial tomography (CT), PA and LAT Z score correlation increased to r = 0.62; P = 0.0065. In our subjects, the mean LAT Z score was 4.6 times higher than the mean AP Z, contrary to previous observations in normal-weight postmenopausal women. Our findings may be due to increased soft tissue composition and fat inhomogeneity in the LAT scanning field resulting in increased X-ray attenuation in obesity.

  8. A Randomized Controlled Trial to Assess Pain and Magnetic Resonance Imaging-Based (MRI-Based) Structural Spine Changes in Low Back Pain Patients After Yoga Practice

    PubMed Central

    Telles, Shirley; Bhardwaj, Abhishek K.; Gupta, Ram K.; Sharma, Sachin K.; Monro, Robin; Balkrishna, Acharya

    2016-01-01

    Background The present study aimed at determining whether 12 weeks of yoga practice in patients with chronic LBP and MRI-based degenerative changes would result in differences in: (i) self-reported pain, anxiety, and spinal flexibility; and (ii) the structure of the discs or vertebrae. Material/Methods Sixty-two persons with MRI-proven degenerative intervertebral discs (group mean ±S.D., 36.2±6.4 years; 30 females) were randomly assigned to yoga and control groups. However, testing was conducted on only 40 subjects, so only their data are included in this study. The assessments were: self-reported pain, state anxiety, spinal flexibility, and MRI of the lumbosacral spine, performed using a 1.5 Tesla system with a spinal surface column. The yoga group was taught light exercises, physical postures, breathing techniques, and yoga relaxation techniques for 1 hour daily for 3 months. No intervention was given to the control group except for routine medical care. A repeated-measures analysis of variance (ANOVA) with post hoc analyses (which was Bonferroni-adjusted) was used. The Ethics Committee of Patanjali Research Foundation had approved the study which had been registered in the Clinical Trials Registry of India (CTRI/2012/11/003094). Results The yoga group showed a significant reduction in self-reported pain and state anxiety in a before/after comparison at 12 weeks. A few patients in both groups showed changes in the discs and vertebrae at post-intervention assessment. Conclusions Within 12 weeks, yoga practice reduced pain and state anxiety but did not alter MRI-proven changes in the intervertebral discs and in the vertebrae.

  9. Lumbosacral spine x-ray

    MedlinePlus

    X-ray - lumbosacral spine; X-ray - lower spine ... The test is done in a hospital x-ray department or your health care provider's office by an x-ray technician. You will be asked to lie on the x-ray ...

  10. Dendritic Spine Pathology in Schizophrenia

    PubMed Central

    Glausier, Jill R.; Lewis, David A.

    2012-01-01

    Schizophrenia is a neurodevelopmental disorder whose clinical features include impairments in perception, cognition and motivation. These impairments reflect alterations in neuronal circuitry within and across multiple brain regions that are due, at least in part, to deficits in dendritic spines, the site of most excitatory synaptic connections. Dendritic spine alterations have been identified in multiple brain regions in schizophrenia, but are best characterized in layer 3 of the neocortex, where pyramidal cell spine density is lower. These spine deficits appear to arise during development, and thus are likely the result of disturbances in the molecular mechanisms that underlie spine formation, pruning, and/or maintenance. Each of these mechanisms may provide insight into novel therapeutic targets for preventing or repairing the alterations in neural circuitry that mediate the debilitating symptoms of schizophrenia. PMID:22546337

  11. Micromechanics of Sea Urchin spines.

    PubMed

    Tsafnat, Naomi; Fitz Gerald, John D; Le, Hai N; Stachurski, Zbigniew H

    2012-01-01

    The endoskeletal structure of the Sea Urchin, Centrostephanus rodgersii, has numerous long spines whose known functions include locomotion, sensing, and protection against predators. These spines have a remarkable internal microstructure and are made of single-crystal calcite. A finite-element model of the spine's unique porous structure, based on micro-computed tomography (microCT) and incorporating anisotropic material properties, was developed to study its response to mechanical loading. Simulations show that high stress concentrations occur at certain points in the spine's architecture; brittle cracking would likely initiate in these regions. These analyses demonstrate that the organization of single-crystal calcite in the unique, intricate morphology of the sea urchin spine results in a strong, stiff and lightweight structure that enhances its strength despite the brittleness of its constituent material.

  12. Fractures of the cervical spine

    PubMed Central

    Marcon, Raphael Martus; Cristante, Alexandre Fogaça; Teixeira, William Jacobsen; Narasaki, Douglas Kenji; Oliveira, Reginaldo Perilo; de Barros Filho, Tarcísio Eloy Pessoa

    2013-01-01

    OBJECTIVES: The aim of this study was to review the literature on cervical spine fractures. METHODS: The literature on the diagnosis, classification, and treatment of lower and upper cervical fractures and dislocations was reviewed. RESULTS: Fractures of the cervical spine may be present in polytraumatized patients and should be suspected in patients complaining of neck pain. These fractures are more common in men approximately 30 years of age and are most often caused by automobile accidents. The cervical spine is divided into the upper cervical spine (occiput-C2) and the lower cervical spine (C3-C7), according to anatomical differences. Fractures in the upper cervical spine include fractures of the occipital condyle and the atlas, atlanto-axial dislocations, fractures of the odontoid process, and hangman's fractures in the C2 segment. These fractures are characterized based on specific classifications. In the lower cervical spine, fractures follow the same pattern as in other segments of the spine; currently, the most widely used classification is the SLIC (Subaxial Injury Classification), which predicts the prognosis of an injury based on morphology, the integrity of the disc-ligamentous complex, and the patient's neurological status. It is important to correctly classify the fracture to ensure appropriate treatment. Nerve or spinal cord injuries, pseudarthrosis or malunion, and postoperative infection are the main complications of cervical spine fractures. CONCLUSIONS: Fractures of the cervical spine are potentially serious and devastating if not properly treated. Achieving the correct diagnosis and classification of a lesion is the first step toward identifying the most appropriate treatment, which can be either surgical or conservative. PMID:24270959

  13. Are adult patients with Laron syndrome osteopenic? A comparison between dual-energy X-ray absorptiometry and volumetric bone densities.

    PubMed

    Benbassat, Carlos A; Eshed, Varda; Kamjin, Moshe; Laron, Zvi

    2003-10-01

    Severe short stature resulting from a deficiency in IGF-I is a prominent feature of Laron syndrome (LS). Although low bone mineral density (BMD) has been noted in LS patients examined by dual energy x-ray absorptiometry (DEXA), this technique does not take volume into account and may therefore underestimate the true bone density in patients with small bones. The aim of the present study was to evaluate the BMD yielded by DEXA in our LS patients using estimated volumetric values. Volumetric density was calculated with the following formulas: bone mineral apparent density (BMAD) = bone mineral content (BMC)/(area)(3/2) for the lumbar spine and BMAD = BMC/area(2) for the femoral neck. The study sample included 12 patients (mean age, 43.9 yr; mean height, 123.7 cm). Findings were compared with 10 osteopenic subjects without developmental abnormalities (mean age, 56 yr; mean height, 164.8 cm) and 10 healthy control subjects matched for sex and age to the LS patients (mean height, 165.5 cm). BMAD in the LS group was 0.201 +/- 0.02 g/cm(3) at the lumbar spine and 0.201 +/- 0.04 g/cm(3) at the femoral neck; corresponding values for the osteopenic group were 0.130 +/- 0.01 and 0.140 +/- 0.01 g/cm(3), and for the controls, 0.178 +/- 0.03 and 0.192 +/- 0.02 g/cm(3). Although areal BMD was significantly lower in the LS and osteopenic subjects compared with controls (P < 0.02) at both the lumbar spine and femoral neck, BMAD was low (P < 0.01) in the osteopenic group only. In conclusion, DEXA does not seem to be a reliable measure of osteoporosis in patients with LS.

  14. ISSLS PRIZE IN BIOENGINEERING SCIENCE 2017: Automation of reading of radiological features from magnetic resonance images (MRIs) of the lumbar spine without human intervention is comparable with an expert radiologist.

    PubMed

    Jamaludin, Amir; Lootus, Meelis; Kadir, Timor; Zisserman, Andrew; Urban, Jill; Battié, Michele C; Fairbank, Jeremy; McCall, Iain

    2017-05-01

    Investigation of the automation of radiological features from magnetic resonance images (MRIs) of the lumbar spine. To automate the process of grading lumbar intervertebral discs and vertebral bodies from MRIs. MR imaging is the most common imaging technique used in investigating low back pain (LBP). Various features of degradation, based on MRIs, are commonly recorded and graded, e.g., Modic change and Pfirrmann grading of intervertebral discs. Consistent scoring and grading is important for developing robust clinical systems and research. Automation facilitates this consistency and reduces the time of radiological analysis considerably and hence the expense. 12,018 intervertebral discs, from 2009 patients, were graded by a radiologist and were then used to train: (1) a system to detect and label vertebrae and discs in a given scan, and (2) a convolutional neural network (CNN) model that predicts several radiological gradings. The performance of the model, in terms of class average accuracy, was compared with the intra-observer class average accuracy of the radiologist. The detection system achieved 95.6% accuracy in terms of disc detection and labeling. The model is able to produce predictions of multiple pathological gradings that consistently matched those of the radiologist. The model identifies 'Evidence Hotspots' that are the voxels that most contribute to the degradation scores. Automation of radiological grading is now on par with human performance. The system can be beneficial in aiding clinical diagnoses in terms of objectivity of gradings and the speed of analysis. It can also draw the attention of a radiologist to regions of degradation. This objectivity and speed is an important stepping stone in the investigation of the relationship between MRIs and clinical diagnoses of back pain in large cohorts. Level 3.

  15. Osteoporosis Imaging: State of the Art and Advanced Imaging

    PubMed Central

    2012-01-01

    Osteoporosis is becoming an increasingly important public health issue, and effective treatments to prevent fragility fractures are available. Osteoporosis imaging is of critical importance in identifying individuals at risk for fractures who would require pharmacotherapy to reduce fracture risk and also in monitoring response to treatment. Dual x-ray absorptiometry is currently the state-of-the-art technique to measure bone mineral density and to diagnose osteoporosis according to the World Health Organization guidelines. Motivated by a 2000 National Institutes of Health consensus conference, substantial research efforts have focused on assessing bone quality by using advanced imaging techniques. Among these techniques aimed at better characterizing fracture risk and treatment effects, high-resolution peripheral quantitative computed tomography (CT) currently plays a central role, and a large number of recent studies have used this technique to study trabecular and cortical bone architecture. Other techniques to analyze bone quality include multidetector CT, magnetic resonance imaging, and quantitative ultrasonography. In addition to quantitative imaging techniques measuring bone density and quality, imaging needs to be used to diagnose prevalent osteoporotic fractures, such as spine fractures on chest radiographs and sagittal multidetector CT reconstructions. Radiologists need to be sensitized to the fact that the presence of fragility fractures will alter patient care, and these fractures need to be described in the report. This review article covers state-of-the-art imaging techniques to measure bone mineral density, describes novel techniques to study bone quality, and focuses on how standard imaging techniques should be used to diagnose prevalent osteoporotic fractures. © RSNA, 2012 PMID:22438439

  16. Predicting skeletal muscle mass from dual-energy X-ray absorptiometry in Japanese prepubertal children.

    PubMed

    Midorikawa, T; Ohta, M; Hikihara, Y; Torii, S; Sakamoto, S

    2017-10-01

    We aimed to develop regression-based prediction equations for estimating total and regional skeletal muscle mass (SMM) from measurements of lean soft tissue mass (LSTM) using dual-energy X-ray absorptiometry (DXA) and investigate the validity of these equations. In total, 144 healthy Japanese prepubertal children aged 6-12 years were divided into 2 groups: the model development group (62 boys and 38 girls) and the validation group (26 boys and 18 girls). Contiguous MRI images with a 1-cm slice thickness were obtained from the first cervical vertebra to the ankle joints as reference data. The SMM was calculated from the summation of the digitized cross-sectional areas. Total and regional LSTM was measured using DXA. Strong significant correlations were observed between the site-matched SMM (total, arms, trunk and legs) measured by MRI and the LSTM obtained by DXA in the model development group for both boys and girls (R 2 adj =0.86-0.97, P<0.01, standard error of the estimate (SEE)=0.08-0.44 kg). When these SMM prediction equations were applied to the validation group, the measured total (boys 9.47±2.21 kg; girls 8.18±2.62 kg) and regional SMM were very similar to the predicted values for both boys (total SMM 9.40±2.39 kg) and girls (total SMM 8.17±2.57 kg). The results of the Bland-Altman analysis for the validation group did not indicate any bias for either boys or girls with the exception of the arm region for the girls. These results suggest that the DXA-derived prediction equations are precise and accurate for the estimation of total and regional SMM in Japanese prepubertal boys and girls.

  17. [Scoliosis: the bent spine].

    PubMed

    Radl, R; Maafe, M; Ziegler, S

    2011-05-01

    Scoliosis, a permanent abnormal curvature of the spine to the side, is divided into four forms: idiopathic (infantile, juvenile and adolescent, accounting for 80% of cases), neurogenic, congenital and adult scoliosis. Most patients with adolescent idiopathic scoliosis initially have mainly cosmetic problems. However, neurogenic, congenital and adult scoliosis can lead to severe clinical symptoms. The leading symptom is back pain caused by secondary changes. In recent years the Lenke classification has been proven to be a reliable tool for disease classification. Non-progressive scoliosis is usually treated conservatively. In the case of Cobb angles of greater than 50°, surgical therapy is recommended in patients presenting before adulthood. Technical improvements in implants and the optimisation of surgical methods have set a trend in the direction of surgical therapy.

  18. Identification of vertebral deformities in the Polish population by morphometric X-ray absorptiometry - results of the EPOLOS study.

    PubMed

    Skowrońska-Jóźwiak, Elzbieta; Płudowski, Paweł; Karczmarewicz, Elzbieta; Lorenc, Roman; Lewiński, Andrzej

    2009-01-01

    The aim of the study was the determination of the prevalence of asymptomatic vertebral deformities in healthy persons of the Polish population, based on morphometric X-ray absorptiometry (MXA), and comparison of the results with data from literature, obtained by other techniques. The study involved 829 persons, including 520 women and 309 men, aged 18-79 years, untreated for osteoporosis before. The Th(4) to L(4) vertebrae were examined. Lateral scans of the thoracic-lumbar spine were made by an Expert-XL densitometer. Six point digitization was used to calculate the anterior (Ha), central (Hc), and posterior (Hp) height of the Th(4)-L(4) vertebral bodies. The vertebrae were defined as having prevalent deformities when at least one ratio value (Ha/Hp, Hc/Hp, Hp/Hp up, or Hp/Hp low) fell 3 SDs below or even more than the reference mean of that ratio at any vertebral level. The analysis was performed on 9629 vertebrae, of which 167 (1.75%), evaluated as deformed and considered as fractures, were observed in 113 patients (13.63 % of the examined patients). In 81 persons (74% of the patients with fractures; 9.7% of the studied population), single fractures were demonstrated, while in 28 persons, multiple deformities prevailed. Fractures occurred in 108 women (20.7% of the examined women) and 42 men (13.5% of the examined men). The highest incidence of deformities was observed in women over 55 years of age. First-degree deformities dominated. Deformities of the Th(8) and Th(6) vertebrae were most frequently observed. 1. Using MXA, it was found that in the Polish population deformities of vertebrae are common, as was demonstrated in X-ray morphometric studies in the European Vertebral Observation Study (EVOS). 2. Densitometric morphometry, as a non-invasive technique, may become a useful tool in the diagnostics of vertebral fractures.

  19. Enhancing the Radiologist-Patient Relationship through Improved Communication: A Quantitative Readability Analysis in Spine Radiology.

    PubMed

    Hansberry, D R; Donovan, A L; Prabhu, A V; Agarwal, N; Cox, M; Flanders, A E

    2017-06-01

    More than 75 million Americans have less than adequate health literacy skills according to the National Center for Education Statistics. Readability scores are used as a measure of how well populations read and understand patient education materials. The purpose of this study was to assess the readability of Web sites dedicated to patient education for radiologic spine imaging and interventions. Eleven search terms relevant to radiologic spine imaging were searched on the public Internet, and the top 10 links for each term were collected and analyzed to determine readability scores by using 10 well-validated quantitative readability assessments from patient-centered education Web sites. The search terms included the following: x-ray spine, CT spine, MR imaging spine, lumbar puncture, kyphoplasty, vertebroplasty, discogram, myelogram, cervical spine, thoracic spine, and lumbar spine. Collectively, the 110 articles were written at an 11.3 grade level (grade range, 7.1-16.9). None of the articles were written at the American Medical Association and National Institutes of Health recommended 3rd-to-7th grade reading levels. The vertebroplasty articles were written at a statistically significant ( P < .05) more advanced level than the articles for x-ray spine, CT spine, and MR imaging spine. Increasing use of the Internet to obtain health information has made it imperative that on-line patient education be written for easy comprehension by the average American. However, given the discordance between readability scores of the articles and the American Medical Association and National Institutes of Health recommended guidelines, it is likely that many patients do not fully benefit from these resources. © 2017 by American Journal of Neuroradiology.

  20. Cidaroids spines facing ocean acidification.

    PubMed

    Dery, Aurélie; Tran, Phuong Dat; Compère, Philippe; Dubois, Philippe

    2018-07-01

    When facing seawater undersaturated towards calcium carbonates, spines of classical sea urchins (euechinoids) show traces of corrosion although they are covered by an epidermis. Cidaroids (a sister clade of euechinoids) are provided with mature spines devoid of epidermis, which makes them, at first sight, more sensitive to dissolution when facing undersaturated seawater. A recent study showed that spines of a tropical cidaroid are resistant to dissolution due to the high density and the low magnesium concentration of the peculiar external spine layer, the cortex. The biofilm and epibionts covering the spines was also suggested to take part in the spine protection. Here, we investigate the protective role of these factors in different cidaroid species from a broad range of latitude, temperature and depth. The high density of the cortical layer and the cover of biofilm and epibionts were confirmed as key protection against dissolution. The low magnesium concentration of cidaroid spines compared to that of euechinoid ones makes them less soluble in general. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Functional anatomy of the spine.

    PubMed

    Bogduk, Nikolai

    2016-01-01

    Among other important features of the functional anatomy of the spine, described in this chapter, is the remarkable difference between the design and function of the cervical spine and that of the lumbar spine. In the cervical spine, the atlas serves to transmit the load of the head to the typical cervical vertebrae. The axis adapts the suboccipital region to the typical cervical spine. In cervical intervertebrtal discs the anulus fibrosus is not circumferential but is crescentic, and serves as an interosseous ligament in the saddle joint between vertebral bodies. Cervical vertebrae rotate and translate in the sagittal plane, and rotate in the manner of an inverted cone, across an oblique coronal plane. The cervical zygapophysial joints are the most common source of chronic neck pain. By contrast, lumbar discs are well designed to sustain compression loads, but rely on posterior elements to limit axial rotation. Internal disc disruption is the most common basis for chronic low-back pain. Spinal muscles are arranged systematically in prevertebral and postvertebral groups. The intrinsic elements of the spine are innervated by the dorsal rami of the spinal nerves, and by the sinuvertebral nerves. Little modern research has been conducted into the structure of the thoracic spine, or the causes of thoracic spinal pain. © 2016 Elsevier B.V. All rights reserved.

  2. Diagnosis of unstable cervical spine injuries: laboratory support for the use of axial traction to diagnose cervical spine instability.

    PubMed

    Kalantar, Babak S; Hipp, John A; Reitman, Charles A; Dreiangel, Niv; Ben-Galim, Peleg

    2010-10-01

    The ability to detect damage to the intervertebral structures is critical in the management of patients after blunt trauma. A practical and inexpensive method to identify severe structural damage not clearly seen on computed tomography would be of benefit. The objective of this study was to assess whether ligamentous injury in the subaxial cervical spine can be reliably detected by analysis of lateral radiographs taken with and without axial traction. Twelve fresh, whole, postrigor-mortis cadavers were used for this study. Lateral cervical spine radiographs were obtained during the application of 0 N, 89 N, and 178 N of axial traction applied to the head. Progressive incremental sectioning of posterior structures was then performed at C4-C5 with traction imaging repeated after each intervention. Intervertebral distraction was analyzed using computer-assisted software. Almost imperceptible intervertebral separation was found when traction was applied to intact spines. In the subaxial cervical spine, the average posterior disc height consistently increased under traction in severely injured spines. The average disc height increase was 14% of the C4 upper endplate width, compared with an average of 2% in the noninjured spines. A change of more than 5% in posterior disc height under traction was above the 95% confidence interval for intact spines, with sensitivity of 83% and specificity of 80%. Applied force of 89 N (20 lb) was sufficient to demonstrate injury. The combination of assessing alignment and distraction under traction increased both the sensitivity and specificity to nearly 100%. This study supports further clinical investigations to determine whether low-level axial traction may be a useful adjunct for detecting unstable subaxial cervical spine injuries in an acute setting.

  3. The Influence of Exogenous Fat and Water on Lumbar Spine Bone Mineral Density in Healthy Volunteers

    PubMed Central

    Kim, Kyu-Nam; Kim, Bom-Taeck; Kim, Kwang-Min; Park, Sat-Byul; Joo, Nam-Seok; Je, Sang Hyeon; Kim, Young-Sang

    2012-01-01

    Purpose Changes in human body composition can affect the accuracy of spine bone mineral density (BMD) measurements. The purpose of this study was to evaluate whether fat and water in the soft tissue of the abdomen influence lumbar spine BMD measurements obtained using dual energy X-ray absorptiometry (DXA). Materials and Methods Duplicate BMD measurements were carried out on healthy volunteers (10 men and 10 women) and the Hologic anthropomorphic spine phantom had on the same day before and after placement of following 3 materials in the abdominal area: lard 900 g, 1.5 cm thick; oil 1.4 liters in a vinyl bag; and water 1.2 liters in a vinyl bag. Results In the case of human participants, following the placement of exogenous water to mimic extracellular fluid (ECF), there was a significant decrease in lumbar spine BMD (-0.012 g/cm2, p=0.006), whereas the placement of exogenous lard and oil to mimic abdominal fat produced a slight increase in lumbar spine BMD (0.006 g/cm2, p=0.301; 0.008 g/cm2, p=0.250, respectively). The average percentage of lumbar spine BMD change with and without exogenous lard, oil, and water showed increase of 0.51%, and 0.67%, and decrease of 1.02%, respectively. Using the phantom, BMD decreased with the placement of both lard (-0.002 g/cm2, p=0.699) and water (-0.006 g/cm2, p=0.153); however, there was no difference in BMD after oil placement. Conclusion These results suggest that in cases where changes in fat and ECF volume are similar, ECF exerts a greater influence than fat on DXA lumbar BMD measurements. PMID:22318815

  4. Validation of a New Skinfold Prediction Equation Based on Dual-Energy X-Ray Absorptiometry

    ERIC Educational Resources Information Center

    Ball, Stephen; Cowan, Celsi; Thyfault, John; LaFontaine, Tom

    2014-01-01

    Skinfold prediction equations recommended by the American College of Sports Medicine underestimate body fat percentage. The purpose of this research was to validate an alternative equation for men created from dual energy x-ray absorptiometry. Two hundred ninety-seven males, aged 18-65, completed a skinfold assessment and dual energy x-ray…

  5. Comparison of Anthropometry to Dual Energy X-Ray Absorptiometry: A New Prediction Equation for Women

    ERIC Educational Resources Information Center

    Ball, Stephen; Swan, Pamela D.; DeSimone, Rosemarie

    2004-01-01

    The purpose of this study was to assess the accuracy of three recommended anthropometric equations for women and then develop an updated prediction equation using dual energy x-ray absorptiometry (DXA). The percentage of body fat (%BF) by anthropometry was significantly correlated (r = .896-. 929; p [is less than] .01) with DXA, but each equation…

  6. Aspergillus osteomyelitis of the spine.

    PubMed

    Govender, S; Rajoo, R; Goga, I E; Charles, R W

    1991-07-01

    Aspergillosis involving either the vertebral body or the intervertebral disc is a rare cause of osteomyelitis of the spine. The following is a report of five cases of Aspergillus fumigatus infection of the spine treated successfully with amphotericin B and 5-flucytosine. In three patients, the diagnosis was established at closed-needle biopsy; two patients with paraplegia had an anterior decompression and fusion. The follow-up period ranged from 19 to 48 months.

  7. [Iliac spine fractures in children].

    PubMed

    Sułko, Jerzy; Olipra, Wojciech

    2010-01-01

    Iliac spine fractures in children are a form of avulsion fractures at mechanically weak spot caused by the presence of the growth plate. Presentation of observations concerning treatment and results of iliac spine fractures in children. 49 children (1 girl and 48 boys). Age, at the time of injury, average 15.1 years (10.6-18 years). We analyzed medical and radiological documentation of patients. 17 patients sustained anterior superior iliac spine fractures (ASIS), 32 fracture of the inferior iliac spine (AIIS). Most of injuries happened during sport activities--27 patients suffered fracture while playing football. 37 patients asked for medical advice immediately after the injury. Rest of patients, who came late--sustained AIIS fracture. We hospitalized 26 patients (53%), all of them suffered significant pain. The average length of stay in hospital was 8 days. All patients were treated conservatively. All of the fractures healed without complications. Larger study than ours group, concerning 84 patients with iliac spine fractures, was presented only by Italian authors who analyzed injures of professional athletes. In literature reviewed conservative treatment strongly predominates. Only a small group of patients were treated surgically (including athletes treated by Croatian surgeons). The treatment of iliac spines in children should be conservative, consisting of a couple days of bed rest and then for 2-3 weeks walking on crutches with only toe touching until the pain resolves. We recommend return to full activities after 2 months.

  8. Injuries of the spine sustained whilst surfboard riding.

    PubMed

    Dimmick, Simon; Brazier, Daivd; Wilson, Peter; Anderson, Suzanne E

    2013-01-01

    Surfboard riding is a popular sport worldwide. Although surfing is considered a 'safe' pastime, significant injuries do occur, particularly to the head and cervical spine. Spinal injuries most commonly occur when the surfer's head strikes the seafloor. This case series identifies the spectrum of spinal pathologies sustained whilst surfing and their imaging appearances. No similar study has previously been published.

  9. Postoperative magnetic resonance imaging artifact with cobalt-chromium versus titanium spinal instrumentation: presented at the 2013 Joint Spine Section Meeting. Clinical article.

    PubMed

    Ahmad, Faiz U; Sidani, Charif; Fourzali, Roberto; Wang, Michael Y

    2013-11-01

    Cobalt-chromium alloy (CoCr) rods haves some preferred biomechanical properties over titanium rods for spinal fixation. The use of CoCr rods in spinal fusion is relatively new, and there is no study in the existing world literature assessing the artifact caused by these rods in patients undergoing postoperative MRI. The purpose of this study is to compare the amount of imaging artifact caused by these implants and to assess its impact on the visualization of neighboring neural structures. This study investigated MR images in patients who underwent implantation of thoracolumbar instrumentation using 5.5-mm-diameter CoCr rods between November 2009 and March 2011 and images obtained in a comparison group of patients who had 5.5-mm titanium rods implanted during the same time period. Axial measurements of the artifact created by the rods between the screw heads were compared between the groups. Two blinded board-certified radiologists performed the measurements independently. They scored the visualization of the spinal canal using a subjective scoring system of 1-3, with 1 representing very good visualization and 2 and 3 representing reduced (good or suboptimal, respectively) visualization as a result of rod-related artifact. All measurements and scores were independently provided for T1-weighted and T2-weighted fast spin echo sequences (1.5-T magnet, 5-mm slice thickness). A total of 40 levels from the CoCr group (6 patients) and 30 levels from the titanium group (9 patients) were included in the analysis. Visualization of the canal at all levels was rated a score of 1 (very good) by both evaluators for both the CoCr and titanium groups. The average artifact on T1-weighted images measured 11.8 ± 1.8 mm for the CoCr group and 8.5 ± 1.2 mm for the titanium group (p < 0.01). The corresponding measurements on T2-weighted images were 11.0 ± 2.3 mm and 8.3 ± 1.7 mm (p < 0.01), respectively. In a mixed regression model, the mean artifact measurement for the CoCr group

  10. Provider Distribution Changes in Dual-Energy X-Ray Absorptiometry in the Medicare Population Over the Past Decade.

    PubMed

    Intenzo, Charles M; Parker, Laurence; Levin, David C; Kim, Sung M; Rao, Vijay M

    2016-01-01

    Both radiologists as well as nonimaging physicians perform dual-energy X-ray absorptiometry (DXA) imaging in the United States. This study aims to compare provider distribution between these physician groups on the Medicare population, which is the predominant age group of patients evaluated by this imaging procedure. Using the 2 relevant Current Procedural Terminology, Fourth Edition codes for DXA scans, source data were obtained from the CMS Physician Supplier Procedure Summary Master Files from 2003 through 2013. DXA scan procedure volumes for radiologists and nonradiologists on Medicare patients were tabulated. Utilization rates were calculated. From 2003 to 2013, the total number of DXA scans performed on Medicare patients decreased by 2%. However, over the same period, the number of scans performed by radiologists had increased by 25% over nonimaging specialists, whose utilization had declined by approximately the same amount. From 2003 to 2013, the rate of utilization of DXA scans in the Medicare fee-for-service population declined somewhat. However, radiologists continue to gain market share from other specialists and now predominate in this type of imaging by a substantial margin. Copyright © 2016 International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

  11. Accuracy of the Canadian C-spine rule and NEXUS to screen for clinically important cervical spine injury in patients following blunt trauma: a systematic review

    PubMed Central

    Michaleff, Zoe A.; Maher, Chris G.; Verhagen, Arianne P.; Rebbeck, Trudy; Lin, Chung-Wei Christine

    2012-01-01

    Background: There is uncertainty about the optimal approach to screen for clinically important cervical spine (C-spine) injury following blunt trauma. We conducted a systematic review to investigate the diagnostic accuracy of the Canadian C-spine rule and the National Emergency X-Radiography Utilization Study (NEXUS) criteria, 2 rules that are available to assist emergency physicians to assess the need for cervical spine imaging. Methods: We identified studies by an electronic search of CINAHL, Embase and MEDLINE. We included articles that reported on a cohort of patients who experienced blunt trauma and for whom clinically important cervical spine injury detectable by diagnostic imaging was the differential diagnosis; evaluated the diagnostic accuracy of the Canadian C-spine rule or NEXUS or both; and used an adequate reference standard. We assessed the methodologic quality using the Quality Assessment of Diagnostic Accuracy Studies criteria. We used the extracted data to calculate sensitivity, specificity, likelihood ratios and post-test probabilities. Results: We included 15 studies of modest methodologic quality. For the Canadian C-spine rule, sensitivity ranged from 0.90 to 1.00 and specificity ranged from 0.01 to 0.77. For NEXUS, sensitivity ranged from 0.83 to 1.00 and specificity ranged from 0.02 to 0.46. One study directly compared the accuracy of these 2 rules using the same cohort and found that the Canadian C-spine rule had better accuracy. For both rules, a negative test was more informative for reducing the probability of a clinically important cervical spine injury. Interpretation: Based on studies with modest methodologic quality and only one direct comparison, we found that the Canadian C-spine rule appears to have better diagnostic accuracy than the NEXUS criteria. Future studies need to follow rigorous methodologic procedures to ensure that the findings are as free of bias as possible. PMID:23048086

  12. Injury of the posterior ligamentous complex of the thoracolumbar spine: a prospective evaluation of the diagnostic accuracy of magnetic resonance imaging.

    PubMed

    Vaccaro, Alexander R; Rihn, Jeffrey A; Saravanja, Davor; Anderson, David G; Hilibrand, Alan S; Albert, Todd J; Fehlings, Michael G; Morrison, William; Flanders, Adam E; France, John C; Arnold, Paul; Anderson, Paul A; Friel, Brian; Malfair, David; Street, John; Kwon, Brian; Paquette, Scott; Boyd, Michael; Dvorak, Marcel F S; Fisher, Charles

    2009-11-01

    Prospective diagnostic imaging study. To determine the accuracy of magnetic resonance imaging (MRI) in diagnosing injury of the posterior ligamentous complex (PLC) in patients with thoracolumbar trauma. Treatment decisions in thoracolumbar injury patients are currently based on the status of the PLC. It is, therefore, important to understand the accuracy of MRI in diagnosing varying degrees of PLC injury. Prior studies report that MRI is up to 100% sensitive for diagnosing PCL injury. Patients with an acute injury from T1 to L3 who required posterior surgery were prospectively studied. A musculoskeletal radiologist, based on the preoperative MRI findings, characterized each of the 6 components of the PLC as intact, incompletely disrupted, or disrupted. During the surgical procedure, the surgeon identified each component of the PLC as intact, incompletely disrupted, or disrupted. The radiologist's interpretation and surgical findings were compared. Forty-two patients with 62 levels of injury were studied. There were 33 males (78.6%) and 9 females (21.4%), and the average age was 35.7 years. According to the kappa score, there was a moderate level of agreement between the radiologist's interpretation and the intraoperative findings for all PLC components except the thoracolumbar fascia, for which there was slight agreement. The sensitivity for the various PLC components ranged from 79% (left facet capsule) to 90% (interspinous ligament). The specificity ranged from 53% (thoracolumbar fascia) to 65% (ligamentum flavum). There was less agreement between the radiologist and surgeon for the patients with less severe neurologic compromise, i.e., those patients with an AIS grade of either D or E. The sensitivity and specificity of MRI for diagnosing injury of the PLC are lower than previously reported in the literature. The integrity of the PLC as determined by MRI should not be used in isolation to determine treatment.

  13. Changing views of Cajal's neuron: the case of the dendritic spine.

    PubMed

    Segal, Menahem

    2002-01-01

    Ever since dendritic spines were first described in detail by Santiago Ramón y Cajal, they were assumed to underlie the physical substrate of long term memory in the brain. Recent time-lapse imaging of dendritic spines in live tissue, using confocal microscopy, have revealed an amazingly plastic structure, which undergoes continuous changes in shape and size, not intuitively related to its assumed role in long term memory. Functionally, the spine is shown to be an independent cellular compartment, able to regulate calcium concentration independently of its parent dendrite. The shape of the spine is instrumental in regulating the link between the synapse and the parent dendrite such that longer spines have less impact on the dendrite than shorter ones. The spine can be formed, change its shape and disappear in response to afferent stimulation, in a dynamic fashion, indicating that spine morphology is an important vehicle for structuring synaptic interactions. While this role is crucial in the developing nervous system, large variations in spine densities in the adult brain indicate that tuning of synaptic impact may be a role of spines throughout the life of a neuron.

  14. A Retrospective Study of Cervical Spine MRI Findings in Children with Abusive Head Trauma.

    PubMed

    Governale, Lance S; Brink, Farah W; Pluto, Charles P; Schunemann, Victoria A; Weber, Rachel; Rusin, Jerome; Fischer, Beth A; Letson, Megan M

    2018-01-01

    Increasing attention has been given to the possible association of cervical spine (c-spine) injuries with abusive head trauma (AHT). The aims of this study were to describe c-spine MRI findings in hospitalized AHT patients. This is a retrospective study of children under the age of 5 years with AHT admitted to hospital in 2004-2013. Those with c-spine MRI were identified, and the images were reviewed. 250 AHT cases were identified, with 34 (14%) undergoing c-spine MRI. Eleven patients (32%) had 25 findings, including hematoma in 2, occiput-C1-C2 edema in 3, prevertebral edema in 6, facet edema in 2, and interspinous and/or muscular edema in 10. No patients had a clinically evident c-spine injury, a clinically unstable c-spine, or required c-spine surgery. C-spine MRI may identify abnormalities not apparent upon physical examination and the procedure should therefore be considered in cases of suspected AHT. © 2017 S. Karger AG, Basel.

  15. Spinal hyperostosis as an important sign indicating spine injuries on postmortem computed tomography.

    PubMed

    Oshima, Toru; Hayashida, Mitsumasa; Ohtani, Maki; Hashimoto, Manabu; Takahashi, Satoshi; Ishiyama, Koichi; Otani, Takahiro; Koga, Makoto; Sugawara, Makoto; Mimasaka, Sohtaro

    2014-07-01

    Although spine injuries are not always detectable on postmortem computed tomography (PMCT), spinal hyperostosis, an important risk factor for spine injury, is relatively easily detectable on PMCT. We therefore examined the utility of the detection of spinal hyperostosis on PMCT as an indicator of spine injury. Full-body PMCT images of 88 autopsy cases with a bruise on the face or forehead but no identifiable skull fracture were reviewed prior to autopsy for the identification and classification of spinal hyperostosis. Spine injuries were observed in 56.0% of cases with spinal hyperostosis and 1.6% of cases without spinal hyperostosis. Among the cases with spinal hyperostosis, spine injuries were observed in 66.7% of cases at stage 2 or 3 and in 88.9% of cases at stage 3. Spine injuries were diagnosed on PMCT in 33.3% of cases prior to autopsy. A significant association was found between spinal hyperostosis and presence of spine injury that cannot be detected on PMCT, indicating that the identification of spinal hyperostosis on PMCT may assist in detecting spine injuries. This finding suggests that investigation of the presence of spine injury based on the identification of spinal hyperostosis on PMCT may assist in determining the correct cause of death by autopsy. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  16. Osteoporosis in Cervical Spine Surgery.

    PubMed

    Guzman, Javier Z; Feldman, Zachary M; McAnany, Steven; Hecht, Andrew C; Qureshi, Sheeraz A; Cho, Samuel K

    2016-04-01

    Retrospective administrative database analysis. To investigate the effect of osteoporosis (OS) on complications and outcomes in patients undergoing cervical spine surgery. OS is the most prevalent degenerative human bone disease, and spine surgeons will inevitably perform procedures on patients with OS. These patients might present a difficult patient cohort because many fixation techniques depend on bone quality and adequate bone healing--both of which are compromised in OS. The nationwide inpatient sample was queried using the Ninth Revision, Clinical Modification procedural codes for cervical spine procedures and diagnosis codes for degenerative conditions of cervical spine from 2002 to 2011. Patients were separated into two cohorts, those patients with OS and those without OS. Demographics, hospital characteristics, and adjusted complication likelihood were analyzed. Multivariate regression analysis was performed to determine odds of revision surgery in patients with OS. Of all patients undergoing degenerative cervical spine surgery, 2% were identified as having OS (32,557 of a sample of 1,602,129 patients). Osteoporotic patients were more likely to undergo posterior cervical spine fusion when compared with those patients without OS (11.3% vs. 5.4%, P < 0.0001). Moreover, circumferential fusion was performed 3 times more frequently in the osteoporotic cohort. Adjusted complications showed increased odds for postoperative hemorrhage (odds ratio = 1.70, 95% confidence interval = 1.46-1.98, P < 0.0001). Patients with OS stayed in the hospital longer (3.5 vs. 2.5 days, P < 0.0001) and had 30% costlier hospitalizations. Multivariate for revision surgery indicated that osteoporotic patients had significantly increased odds of revision surgery (odds ratio = 1.54, P ≤ 0.0001) when referenced to non-osteoporotic patients undergoing cervical spine surgery. Osteoporotic patients were more likely to undergo revision surgery, have longer

  17. Prickly Pear Spine Keratoconjunctivitis

    PubMed Central

    Odat, Thabit Ali Mustafa; Al-Tawara, Mohammad Jebreel; Hammouri, Eman Hussein

    2014-01-01

    Objectives: To study the ocular and extra-ocular features, clinical presentation, and treatment of prickly pear glochids. Materials and Methods: This retrospective study included 23 eyes of 21 patients with ocular prickly pear spines who were seen between August and October 2011 in the outpatient ophthalmic clinic at Prince Rashid Bin Al Hassan military hospital in Jordan. Medical records of patients including age, gender, history of exposure to prickly pear plants, and ocular examination were reviewed. All glochids were localized and removed with forceps under topical anesthesia with the patient at the slit lamp. Patients were followed up after one week. Results: The mean age of patients was 37.1 years with a male to female ratio of 1.6: 1. Involvement of the right eye was seen in 61.9% patients, left eye in 28.6% patients, and bilateral involvement in 9.5% patients. Glochids were most commonly found in the upper subtarsal conjunctival space (47.6%) followed by inferior palpebral conjunctiva in 23.8% eyes. The most common complaint was eye irritation in 95.2% patients. Pain was a complaint in 57.1% patients. Superior corneal epithelial erosions or ulcer were found in 33.3% patients, inferior corneal epithelial erosions in 19.1% patients, and diffuse epithelial erosions in 9.5% patients. Glochids were found in other parts of the body in 38.1% patients. Conclusion: Although prickly pear glochid ocular surface injury is not uncommon in the region during summer, it should be considered in patient with eye pain during that period. Farmers who are in close contact with prickly pears should use protective eyeglasses and gloves. PMID:24669148

  18. Musical representation of dendritic spine distribution: a new exploratory tool.

    PubMed

    Toharia, Pablo; Morales, Juan; de Juan, Octavio; Fernaud, Isabel; Rodríguez, Angel; DeFelipe, Javier

    2014-04-01

    Dendritic spines are small protrusions along the dendrites of many types of neurons in the central nervous system and represent the major target of excitatory synapses. For this reason, numerous anatomical, physiological and computational studies have focused on these structures. In the cerebral cortex the most abundant and characteristic neuronal type are pyramidal cells (about 85 % of all neurons) and their dendritic spines are the main postsynaptic target of excitatory glutamatergic synapses. Thus, our understanding of the synaptic organization of the cerebral cortex largely depends on the knowledge regarding synaptic inputs to dendritic spines of pyramidal cells. Much of the structural data on dendritic spines produced by modern neuroscience involves the quantitative analysis of image stacks from light and electron microscopy, using standard statistical and mathematical tools and software developed to this end. Here, we present a new method with musical feedback for exploring dendritic spine morphology and distribution patterns in pyramidal neurons. We demonstrate that audio analysis of spiny dendrites with apparently similar morphology may "sound" quite different, revealing anatomical substrates that are not apparent from simple visual inspection. These morphological/music translations may serve as a guide for further mathematical analysis of the design of the pyramidal neurons and of spiny dendrites in general.

  19. Single fraction spine radiosurgery for myeloma epidural spinal cord compression.

    PubMed

    Jin, Ryan; Rock, Jack; Jin, Jian-Yue; Janakiraman, Nalini; Kim, Jae Ho; Movsas, Benjamin; Ryu, Samuel

    2009-01-01

    Radiosurgery delivers highly focused radiation beams to the defined target with high precision and accuracy. It has been demonstrated that spine radiosurgery can be safely used for treatment of spine metastasis with rapid and durable pain control, but without detrimental effects to the spinal cord. This study was carried out to determine the role of single fraction radiosurgery for epidural spinal cord compression due to multiple myeloma. A total of 31 lesions in 24 patients with multiple myeloma, who presented with epidural spinal cord compression, were treated with spine radiosurgery. Single fraction radiation dose of 10-18 Gy (median of 16 Gy) was administered to the involved spine including the epidural or paraspinal tumor. Patients were followed up with clinical exams and imaging studies. Median follow-up was 11.2 months (range 1-55). Primary endpoints of this study were pain control, neurological improvement, and radiographic tumor control. Overall pain control rate was 86%; complete relief in 54%, and partial relief in 32% of the patients. Seven patients presented with neurological deficits. Five patients neurologically improved or became normal after radiosurgery. Complete radiographic response of the epidural tumor was noted in 81% at 3 months after radiosurgery. During the follow-up time, there was no radiographic or neurological progression at the treated spine. The treatment was non-invasive and well tolerated. Single fraction radiosurgery achieved an excellent clinical and radiographic response of myeloma epidural spinal cord compression. Radiosurgery can be a viable treatment option for myeloma epidural compression.

  20. Are the determinants of vertebral endplate changes and severe disc degeneration in the lumbar spine the same? A magnetic resonance imaging study in middle-aged male workers.

    PubMed

    Kuisma, Mari; Karppinen, Jaro; Haapea, Marianne; Niinimäki, Jaakko; Ojala, Risto; Heliövaara, Markku; Korpelainen, Raija; Kaikkonen, Kaisu; Taimela, Simo; Natri, Antero; Tervonen, Osmo

    2008-04-16

    Modic changes are bone marrow lesions visible in magnetic resonance imaging (MRI), and they are assumed to be associated with symptomatic intervertebral disc disease, especially changes located at L5-S1. Only limited information exists about the determinants of Modic changes. The objective of this study was to evaluate the determinants of vertebral endplate (Modic) changes, and whether they are similar for Modic changes and severe disc degeneration focusing on L5-S1 level. 228 middle-aged male workers (159 train engineers and 69 sedentary factory workers) from northern Finland underwent sagittal T1- and T2-weighted MRI. Modic changes and disc degeneration were analyzed from the scans. The participants responded to a questionnaire including items of occupational history and lifestyle factors. Logistic regression analysis was used to evaluate the associations between selected determinants (age, lifetime exercise, weight-related factors, fat percentage, smoking, alcohol use, lifetime whole-body vibration) and Modic type I and II changes, and severe disc degeneration (= grade V on Pfirrmann's classification). The prevalences of the Modic changes and severe disc degeneration were similar in the occupational groups. Age was significantly associated with all degenerative changes. In the age-adjusted analyses, only weight-related determinants (BMI, waist circumference) were associated with type II changes. Exposure to whole-body vibration, besides age, was the only significant determinant for severe disc degeneration. In the multivariate model, BMI was associated with type II changes at L5-S1 (OR 2.75 per one SD = 3 unit increment in BMI), and vibration exposure with severe disc degeneration at L5-S1 (OR 1.08 per one SD = 11-year increment in vibration exposure). Besides age, weight-related factors seem important in the pathogenesis of Modic changes, whereas whole-body vibration was the only significant determinant of severe disc degeneration.

  1. Are the determinants of vertebral endplate changes and severe disc degeneration in the lumbar spine the same? A magnetic resonance imaging study in middle-aged male workers

    PubMed Central

    Kuisma, Mari; Karppinen, Jaro; Haapea, Marianne; Niinimäki, Jaakko; Ojala, Risto; Heliövaara, Markku; Korpelainen, Raija; Kaikkonen, Kaisu; Taimela, Simo; Natri, Antero; Tervonen, Osmo

    2008-01-01

    Background Modic changes are bone marrow lesions visible in magnetic resonance imaging (MRI), and they are assumed to be associated with symptomatic intervertebral disc disease, especially changes located at L5-S1. Only limited information exists about the determinants of Modic changes. The objective of this study was to evaluate the determinants of vertebral endplate (Modic) changes, and whether they are similar for Modic changes and severe disc degeneration focusing on L5-S1 level. Methods 228 middle-aged male workers (159 train engineers and 69 sedentary factory workers) from northern Finland underwent sagittal T1- and T2-weighted MRI. Modic changes and disc degeneration were analyzed from the scans. The participants responded to a questionnaire including items of occupational history and lifestyle factors. Logistic regression analysis was used to evaluate the associations between selected determinants (age, lifetime exercise, weight-related factors, fat percentage, smoking, alcohol use, lifetime whole-body vibration) and Modic type I and II changes, and severe disc degeneration (= grade V on Pfirrmann's classification). Results The prevalences of the Modic changes and severe disc degeneration were similar in the occupational groups. Age was significantly associated with all degenerative changes. In the age-adjusted analyses, only weight-related determinants (BMI, waist circumference) were associated with type II changes. Exposure to whole-body vibration, besides age, was the only significant determinant for severe disc degeneration. In the multivariate model, BMI was associated with type II changes at L5-S1 (OR 2.75 per one SD = 3 unit increment in BMI), and vibration exposure with severe disc degeneration at L5-S1 (OR 1.08 per one SD = 11-year increment in vibration exposure). Conclusion Besides age, weight-related factors seem important in the pathogenesis of Modic changes, whereas whole-body vibration was the only significant determinant of severe disc

  2. Robotic systems in spine surgery.

    PubMed

    Onen, Mehmet Resid; Naderi, Sait

    2014-01-01

    Surgical robotic systems have been available for almost twenty years. The first surgical robotic systems were designed as supportive systems for laparoscopic approaches in general surgery (the first procedure was a cholecystectomy in 1987). The da Vinci Robotic System is the most common system used for robotic surgery today. This system is widely used in urology, gynecology and other surgical disciplines, and recently there have been initial reports of its use in spine surgery, for transoral access and anterior approaches for lumbar inter-body fusion interventions. SpineAssist, which is widely used in spine surgery, and Renaissance Robotic Systems, which are considered the next generation of robotic systems, are now FDA approved. These robotic systems are designed for use as guidance systems in spine instrumentation, cement augmentations and biopsies. The aim is to increase surgical accuracy while reducing the intra-operative exposure to harmful radiation to the patient and operating team personnel during the intervention. We offer a review of the published literature related to the use of robotic systems in spine surgery and provide information on using robotic systems.

  3. Magnetic Resonance Imaging Assessment of Spinal Cord and Cauda Equina Motion in Supine Patients With Spinal Metastases Planned for Spine Stereotactic Body Radiation Therapy

    SciTech Connect

    Tseng, Chia-Lin; Department of Radiation Oncology, Princess Margaret Cancer Centre, University of Toronto, Toronto, Ontario; Sussman, Marshall S.

    2015-04-01

    Purpose: To assess motion of the spinal cord and cauda equina, which are critical neural tissues (CNT), which is important when evaluating the planning organ-at-risk margin required for stereotactic body radiation therapy. Methods and Materials: We analyzed CNT motion in 65 patients with spinal metastases (11 cervical, 39 thoracic, and 24 lumbar spinal segments) in the supine position using dynamic axial and sagittal magnetic resonance imaging (dMRI, 3T Verio, Siemens) over a 137-second interval. Motion was segregated according to physiologic cardiorespiratory oscillatory motion (characterized by the average root mean square deviation) and random bulk shifts associated with gross patient motionmore » (characterized by the range). Displacement was evaluated in the anteroposterior (AP), lateral (LR), and superior-inferior (SI) directions by use of a correlation coefficient template matching algorithm, with quantification of random motion measure error over 3 separate trials. Statistical significance was defined according to P<.05. Results: In the AP, LR, and SI directions, significant oscillatory motion was observed in 39.2%, 35.1%, and 10.8% of spinal segments, respectively, and significant bulk motions in all cases. The median oscillatory CNT motions in the AP, LR, and SI directions were 0.16 mm, 0.17 mm, and 0.44 mm, respectively, and the maximal statistically significant oscillatory motions were 0.39 mm, 0.41 mm, and 0.77 mm, respectively. The median bulk displacements in the AP, LR, and SI directions were 0.51 mm, 0.59 mm, and 0.66 mm, and the maximal statistically significant displacements were 2.21 mm, 2.87 mm, and 3.90 mm, respectively. In the AP, LR, and SI directions, bulk displacements were greater than 1.5 mm in 5.4%, 9.0%, and 14.9% of spinal segments, respectively. No significant differences in axial motion were observed according to cord level or cauda equina. Conclusions: Oscillatory CNT motion was observed to be relatively minor. Our

  4. Vertebral Fracture Assessment by dual-energy X-ray absorptiometry: insurance coverage issues in the United States. A White Paper of the International Society for Clinical Densitometry.

    PubMed

    Laster, Andrew J; Lewiecki, E Michael

    2007-01-01

    Clinical trial data and fracture risk prediction models unequivocally demonstrate the utility of identifying prevalent vertebral fractures to predict future fractures of all types. Knowledge of prevalent vertebral fractures can alter patient management decisions and result in initiation of therapy to reduce fracture risk in some patients who would not otherwise be treated. Cost-benefit analysis demonstrates that identifying and treating patients with vertebral fractures, even those with a densitometric classification of osteopenia, is cost effective. Vertebral fractures can be readily identified in the office setting using standard radiography or Vertebral Fracture Assessment (VFA), a software addition to a central dual-energy X-ray absorptiometry (DXA) machine. In the United States, VFA was assigned a Current Procedural Terminology (CPT) code in January 2005. Nevertheless, coverage of VFA has not been uniformly embraced by Medicare carriers, companies that contract with the federal government to administer Medicare coverage and process claims for a region of the United States. Unlike DXA, for which uniform national coverage of qualified Medicare beneficiaries is mandated by the Balanced Budget Act of 1997, VFA coverage policies are determined by the local Medicare carriers. Third-party insurers are also variable in their coverage of VFA. This International Society for Clinical Densitometry (ISCD) White Paper documents the role of VFA in the evaluation and treatment of women with postmenopausal osteoporosis and compares it with standard spine radiography. Arguments used by some Medicare carriers and insurers to deny coverage of VFA in the United States are analyzed and critiqued. For health care providers within the United States, this White Paper may serve as a resource to respond to insurers who deny coverage of VFA. For health care providers regardless of their country, this article underscores the value of VFA as an alternative to spine radiography in the

  5. Lynx1 Limits Dendritic Spine Turnover in the Adult Visual Cortex

    PubMed Central

    Sajo, Mari

    2016-01-01

    Dendritic spine turnover becomes limited in the adult cerebral cortex. Identification of specific aspects of spine dynamics that can be unmasked in adulthood and its regulatory molecular mechanisms could provide novel therapeutic targets for inducing plasticity at both the functional and structural levels for robust recovery from brain disorders and injuries in adults. Lynx1, an endogenous inhibitor of nicotinic acetylcholine receptors, was previously shown to increase its expression in adulthood and thus to limit functional ocular dominance plasticity in adult primary visual cortex (V1). However, the role of this “brake” on spine dynamics is not known. We examined the contribution of Lynx1 on dendritic spine turnover before and after monocular deprivation (MD) in adult V1 with chronic in vivo imaging using two-photon microscopy and determined the spine turnover rate of apical dendrites of layer 5 (L5) and L2/3 pyramidal neurons in adult V1 of Lynx1 knock-out (KO) mice. We found that the deletion of Lynx1 doubled the baseline spine turnover rate, suggesting that the spine dynamics in the adult cortex is actively limited by the presence of Lynx1. After MD, adult Lynx1-KO mice selectively exhibit higher rate of spine loss with no difference in gain rate in L5 neurons compared with control wild-type counterparts, revealing a key signature of spine dynamics associated with robust functional plasticity in adult V1. Overall, Lynx1 could be a promising therapeutic target to induce not only functional, but also structural plasticity at the level of spine dynamics in the adult brain. SIGNIFICANCE STATEMENT Dendritic spine turnover becomes limited in the adult cortex. In mouse visual cortex, a premier model of experience-dependent plasticity, we found that the deletion of Lynx1, a nicotinic “brake” for functional plasticity, doubled the baseline spine turnover in adulthood, suggesting that the spine dynamics in the adult cortex is actively limited by Lynx1. After

  6. Whole Body Vibration Training is Osteogenic at the Spine in College-Age Men and Women.

    PubMed

    Ligouri, Gianna C; Shoepe, Todd C; Almstedt, Hawley C

    2012-03-01

    Osteoporosis is a chronic skeletal disease characterized by low bone mass which is currently challenging the American health care system. Maximizing peak bone mass early in life is a cost-effective method for preventing osteoporosis. Whole body vibration (WBV) is a novel exercise method with the potential to increase bone mass, therefore optimizing peak bone and decreasing the risk for osteoporotic fracture. The aim of this investigation was to evaluate changes in bone mineral density at the hip, spine, and whole body in college-age men and women who underwent a WBV training protocol. Active men (n=6) and women (n=4), ages 18-22 participated in the WBV training; while an additional 14 volunteers (1 male, 13 female) served as controls. All participants completed baseline and follow-up questionnaires to assess health history, physical activity, dietary intake, and menstrual history. The WBV training program, using a Vibraflex 550, incorporated squats, stiff-leg dead lifts, stationary lunges, push-up holds, bent-over rows, and jumps performed on the platform, and occurred 3 times a week, for 12 weeks. Dual energy x-ray absorptiometry (Hologic Explorer, Waltham, MA, USA) was used to assess bone mineral density (BMD, g/cm(2)). A two-tailed, t-test identified significantly different changes in BMD between the WBV and control groups at the lateral spine (average change of 0.022 vs. -0.015 g/cm(2)). The WBV group experienced a 2.7% and 1.0% increase in BMD in the lateral spine and posterior-anterior spine while the control group decreased 1.9% and 0.9%, respectively. Results indicate that 12 weeks of WBV training was osteogenic at the spine in college-age men and women.

  7. Diversity of Spine Synapses in Animals

    PubMed Central

    Wang, Ya-Xian; Mattson, Mark P.; Yao, Pamela J.

    2016-01-01

    Here we examine the structure of the various types of spine synapses throughout the animal kingdom. Based on available evidence, we suggest that there are two major categories of spine synapses: invaginating and non-invaginating, with distributions that vary among different groups of animals. In the simplest living animals with definitive nerve cells and synapses, the cnidarians and ctenophores, most chemical synapses do not form spine synapses. But some cnidarians have invaginating spine synapses, especially in photoreceptor terminals of motile cnidarians with highly complex visual organs, and also in some mainly sessile cnidarians with rapid prey capture reflexes. This association of invaginating spine synapses with complex sensory inputs is retained in the evolution of higher animals in photoreceptor terminals and some mechanoreceptor synapses. In contrast to invaginating spine synapse, non-invaginating spine synapses have been described only in animals with bilateral symmetry, heads and brains, associated with greater complexity in neural connections. This is apparent already in the simplest bilaterians, the flatworms, which can have well-developed non-invaginating spine synapses in some cases. Non-invaginating spine synapses diversify in higher animal groups. We also discuss the functional advantages of having synapses on spines and more specifically, on invaginating spines. And finally we discuss pathologies associated with spine synapses, concentrating on those systems and diseases where invaginating spine synapses are involved. PMID:27230661

  8. Micromechanics of Sea Urchin Spines

    PubMed Central

    Tsafnat, Naomi; Fitz Gerald, John D.; Le, Hai N.; Stachurski, Zbigniew H.

    2012-01-01

    The endoskeletal structure of the Sea Urchin, Centrostephanus rodgersii, has numerous long spines whose known functions include locomotion, sensing, and protection against predators. These spines have a remarkable internal microstructure and are made of single-crystal calcite. A finite-element model of the spine’s unique porous structure, based on micro-computed tomography (microCT) and incorporating anisotropic material properties, was developed to study its response to mechanical loading. Simulations show that high stress concentrations occur at certain points in the spine’s architecture; brittle cracking would likely initiate in these regions. These analyses demonstrate that the organization of single-crystal calcite in the unique, intricate morphology of the sea urchin spine results in a strong, stiff and lightweight structure that enhances its strength despite the brittleness of its constituent material. PMID:22984468

  9. Rare cause of neck pain: tumours of the posterior elements of the cervical spine.

    PubMed

    Katsuura, Yoshihiro; Cason, Garrick; Osborn, James

    2016-12-15

    Here we present two cases of primary bone tumours of the cervical spine in patients who had persistent neck pain-in one case, lasting 8 years. In each case, there was a delay in diagnosis and referral to a spine specialist was prolonged. Primary bone tumours of the spine are rare, which is in contrast to the wide prevalence of cervical neck pain. Many primary care providers may go an entire career without encountering a symptomatic primary cervical spine tumour. In this paper, we discuss the clinical course and treatment of each patient and review the current literature on primary bone tumours of the spine. Owing to the subtle roentgenographic findings of primary cervical tumours, we highlight the importance of advanced imaging in the clinical work-up of simple axial neck pain lasting >6 weeks to avoid misdiagnosis of serious pathology. 2016 BMJ Publishing Group Ltd.

  10. Assessment of the dorsal fin spine for chimaeroid (Holocephali: Chimaeriformes) age estimation.

    PubMed

    Barnett, L A K; Ebert, D A; Cailliet, G M

    2009-10-01

    Previous attempts to age chimaeroids have not rigorously tested assumptions of dorsal fin spine growth dynamics. Here, novel imaging and data-analysis techniques revealed that the dorsal fin spine of the spotted ratfish Hydrolagus colliei is an unreliable structure for age estimation. Variation among individuals in the relationship between spine width and distance from the spine tip indicated that the technique of transverse sectioning may impart imprecision and bias to age estimates. The number of growth-band pairs observed by light microscopy in the inner dentine layer was not a good predictor of body size. Mineral density gradients, indicative of growth zones, were absent in the dorsal fin spine of H. colliei, decreasing the likelihood that the bands observed by light microscopy represent a record of growth with consistent periodicity. These results indicate that the hypothesis of aseasonal growth remains plausible and it should not be assumed that chimaeroid age is quantifiable by standard techniques.

  11. Bone mineral density changes of lumbar spine and femur in osteoporotic patient treated with bisphosphonates and beta-hydroxy-beta-methylbutyrate (HMB): Case report.

    PubMed

    Tatara, Marcin R; Krupski, Witold; Majer-Dziedzic, Barbara

    2017-10-01

    Currently available approaches to osteoporosis treatment include application of antiresorptive and anabolic agents influencing bone tissue metabolism. The aim of the study was to present bone mineral density (BMD) changes of lumbar spine in osteoporotic patient treated with bisphosphonates such as ibandronic acid and pamidronic acid, and beta-hydroxy-beta-methylbutyrate (HMB). BMD and volumetric BMD (vBMD) of lumbar spine were measured during the 6 year observation period with the use of dual-energy X-ray absorptiometry (DEXA) and quantitative computed tomography (QCT). The described case report of osteoporotic patient with family history of severe osteoporosis has shown site-dependent response of bone tissue to antiosteoporotic treatment with bisphosphonates. Twenty-five-month treatment with ibandronic acid improved proximal femur BMD with relatively poor effects on lumbar spine BMD. Over 15-month therapy with pamidronic acid was effective to improve lumbar spine BMD, while in the proximal femur the treatment was not effective. A total of 61-week long oral administration with calcium salt of HMB improved vBMD of lumbar spine in the trabecular and cortical bone compartments when monitored by QCT. Positive effects of nearly 2.5 year HMB treatment on BMD of lumbar spine and femur in the patient were also confirmed using DEXA method. The results obtained indicate that HMB may be applied for the effective treatment of osteoporosis in humans. Further studies on wider human population are recommended to evaluate mechanisms influencing bone tissue metabolism by HMB.

  12. Low Bone Mineral Content and Challenges in Interpretation of Dual-Energy X-Ray Absorptiometry in Children With Mucopolysaccharidosis Types I, II, and VI

    PubMed Central

    Polgreen, Lynda E.; Thomas, William; Fung, Ellen; Viskochil, David; Stevenson, David A.; Steinberger, Julia; Orchard, Paul; Whitley, Chester B.; Ensrud, Kristine E.

    2013-01-01

    Osteoporosis has been described in animal models of mucopolysaccharidosis (MPS). Whether clinically significant osteoporosis is common among children with MPS is unknown. Therefore, cross-sectional data from whole body (WB; excluding head) and lumbar spine (LS) bone mineral density (BMD) compared with sex-, chronologic age–, and ethnicity-matched healthy individuals (Zage), height-for-age (HAZ) Z-score (ZHAZ) and bone mineral content (BMC) measured by dual-energy X-ray absorptiometry (DXA) in 40 children with MPS were analyzed. A subset of these children (n = 24) was matched 1:3 by age and sex to a group of healthy children (n = 72) for comparison of BMC adjusted for Tanner stage, race, lean body mass, height, and bone area. Low BMD Z-score was defined as Z-score of −2 or less. In children with MPS, 15% had low WB Zage and 48% had low LS Zage; 0% and 6% had low WB ZHAZ and low LS ZHAZ, respectively. Adjusted WB BMC was lower in MPS participants (p = 0.009). In conclusion, children with MPS had deficits in WB BMC after adjustments for stature and bone area. HAZ adjustment underestimated bone deficits (i.e., overestimated WB BMD Z-scores) in children with MPS likely owing to their abnormal bone shape. The influence of severe short stature and bone geometry on DXA measurements must be considered in children with MPS to avoid unnecessary exposure to antiresorptive treatments. PMID:23562131

  13. Head injuries and the risk of concurrent cervical spine fractures.

    PubMed

    Thesleff, Tuomo; Kataja, Anneli; Öhman, Juha; Luoto, Teemu M

    2017-05-01

    Cervical spine injuries of variable severity are common among patients with an acute traumatic brain injury (TBI). We hypothesised that TBI patients with positive head computed tomography (CT) scans would have a significantly higher risk of having an associated cervical spine fracture compared to patients with negative head CT scans. This widely generalisable retrospective sample was derived from 3,023 consecutive patients, who, due to an acute head injury (HI), underwent head CT at the Emergency Department of Tampere University Hospital (August 2010-July 2012). Medical records were reviewed to identify the individuals whose cervical spine was CT-imaged within 1 week after primary head CT due to a clinical suspicion of a cervical spine injury (CSI) (n = 1,091). Of the whole cranio-cervically CT-imaged sample (n = 1,091), 24.7% (n = 269) had an acute CT-positive TBI. Car accidents 22.4% (n = 244) and falls 47.8% (n = 521) were the most frequent injury mechanisms. On cervical CT, any type of fracture was found in 6.6% (n = 72) and dislocation and/or subluxation in 2.8% (n = 31) of the patients. The patients with acute traumatic intracranial lesions had significantly (p = 0.04; OR = 1.689) more cervical spine fractures (9.3%, n = 25) compared to head CT-negative patients (5.7%, n = 47). On an individual cervical column level, head CT positivity was especially related to C6 fractures (p = 0.031, OR = 2.769). Patients with cervical spine fractures (n = 72) had altogether 101 fractured vertebrae, which were most often C2 (22.8, n = 23), C7 (19.8%, n = 20) and C6 (16.8%, n = 17). Head trauma patients with acute intracranial lesions on CT have a higher risk for cervical spine fractures in comparison to patients with a CT-negative head injury. Although statistically significant, the difference in fracture rate was small. However, based on these results, we suggest that cervical spine fractures should be

  14. Estimates of volumetric bone density from projectional measurements improve the discriminatory capability of dual X-ray absorptiometry

    NASA Technical Reports Server (NTRS)

    Jergas, M.; Breitenseher, M.; Gluer, C. C.; Yu, W.; Genant, H. K.

    1995-01-01

    To determine whether estimates of volumetric bone density from projectional scans of the lumbar spine have weaker associations with height and weight and stronger associations with prevalent vertebral fractures than standard projectional bone mineral density (BMD) and bone mineral content (BMC), we obtained posteroanterior (PA) dual X-ray absorptiometry (DXA), lateral supine DXA (Hologic QDR 2000), and quantitative computed tomography (QCT, GE 9800 scanner) in 260 postmenopausal women enrolled in two trials of treatment for osteoporosis. In 223 women, all vertebral levels, i.e., L2-L4 in the DXA scan and L1-L3 in the QCT scan, could be evaluated. Fifty-five women were diagnosed as having at least one mild fracture (age 67.9 +/- 6.5 years) and 168 women did not have any fractures (age 62.3 +/- 6.9 years). We derived three estimates of "volumetric bone density" from PA DXA (BMAD, BMAD*, and BMD*) and three from paired PA and lateral DXA (WA BMD, WA BMDHol, and eVBMD). While PA BMC and PA BMD were significantly correlated with height (r = 0.49 and r = 0.28) or weight (r = 0.38 and r = 0.37), QCT and the volumetric bone density estimates from paired PA and lateral scans were not (r = -0.083 to r = 0.050). BMAD, BMAD*, and BMD* correlated with weight but not height. The associations with vertebral fracture were stronger for QCT (odds ratio [QR] = 3.17; 95% confidence interval [CI] = 1.90-5.27), eVBMD (OR = 2.87; CI 1.80-4.57), WA BMDHol (OR = 2.86; CI 1.80-4.55) and WA-BMD (OR = 2.77; CI 1.75-4.39) than for BMAD*/BMD* (OR = 2.03; CI 1.32-3.12), BMAD (OR = 1.68; CI 1.14-2.48), lateral BMD (OR = 1.88; CI 1.28-2.77), standard PA BMD (OR = 1.47; CI 1.02-2.13) or PA BMC (OR = 1.22; CI 0.86-1.74). The areas under the receiver operating characteristic (ROC) curves for QCT and all estimates of volumetric BMD were significantly higher compared with standard PA BMD and PA BMC. We conclude that, like QCT, estimates of volumetric bone density from paired PA and lateral scans are

  15. Femoral Neck X-Ray Absorptiometry Parameters and Peripheral Quantitative Computer Tomography Tibial Cortical Density Predict Survival in Dialysis Patients.

    PubMed

    Yap, Natalie; Wong, Phillip; McGinn, Stella; Nery, Maria-Liza; Doyle, Jean; Wells, Lynda; Clifton-Bligh, Phillip; Clifton-Bligh, Roderick J

    2017-01-01

    Low bone mineral density (BMD) is a known independent predictor of mortality in the general elderly population. However, studies in patients with end-stage renal disease (ESRD) are limited. The present study evaluated mortality during long-term follow-up in a population of patients having dialysis for ESRD, in whom BMD was also measured. Fifty-eight patients with ESRD were recruited consecutively from a dialysis clinic and followed prospectively for 6 years. Baseline BMD of the lumbar spine and femoral neck (FN) were measured by X-ray absorptiometry and by peripheral quantitative CT at the radius and tibia. Serum calcium, phosphate, parathyroid hormone (PTH), and albumin were measured at baseline. During follow-up, 25 patients died. Univariate analysis showed that mortality was significantly associated with FN-BMD: hazards ratio (HR) per 0.1 g/cm2 decrease 1.50 (95% CI 1.07-2.10), p = 0.019; FN-T score: HR per 1-SD decrease 1.84 (95% CI 1.16-2.92), p = 0.009; and tibial cortical density: HR per 10 mg/cm3 decrease 1.08 (95% CI 1.02-1.14), p = 0.010. In multivariate analysis with stepwise adjustment for age, sex, transplant status, albumin, PTH, phosphate, dialysis duration, diabetes, and smoking, FN-T score remained significantly associated with mortality: HR per 1-SD decrease 1.82 (95% CI 1.02-3.24), p = 0.044, whereas the HR for FN-BMD and tibial cortical density were no longer significant. When 4 patients who had peritoneal dialysis were excluded, the HR relating FN-BMD, FN-T score, and tibial cortical density to mortality remained significant but became insignificant when albumin was included in the multivariate analysis. Reduced FN-BMD, FN-T score, and tibial cortical density were significantly associated with an increased risk of death in patients with ESRD. © 2017 S. Karger AG, Basel.

  16. Incidence of numerical variants and transitional lumbosacral vertebrae on whole-spine MRI.

    PubMed

    Tins, Bernhard J; Balain, Birender

    2016-04-01

    This study sets out to prospectively investigate the incidence of transitional vertebrae and numerical variants of the spine. Over a period of 28 months, MRIs of the whole spine were prospectively evaluated for the presence of transitional lumbosacral vertebrae and numerical variants of the spine. MRI of the whole spine was evaluated in 420 patients, comprising 211 female and 209 male subjects. Two patients had more complex anomalies. Lumbosacral transitional vertebrae were seen in 12 patients: eight sacralised L5 (3 male, 5 female) and four lumbarised S1 (3 male, 1 female). The incidence of transitional vertebrae was approximately 3.3. % (14/418). Thirty-two (7.7 %) of 418 patients had numerical variants of mobile vertebrae of the spine without transitional vertebrae. The number of mobile vertebrae was increased by one in 18 patients (12 male, 6 female), and the number was decreased by one in 14 patients (4 male, 10 female). Numerical variants of the spine are common, and were found to be almost 2.5 times as frequent as transitional lumbosacral vertebrae in the study population. Only whole-spine imaging can identify numerical variants and the anatomical nature of transitional vertebrae. The tendency is toward an increased number of mobile vertebrae in men and a decreased number in women. Main messages • Numerical variants of the spine are more common than transitional vertebrae. • Spinal numerical variants can be reliably identified only with whole-spine imaging. • Increased numbers of vertebrae are more common in men than women. • Transitional lumbosacral vertebrae occurred in about 3.3 % of the study population. • The incidence of numerical variants of the spine was about 7.7 %.

  17. Primary osseous hemangiopericytoma in the thoracic spine.

    PubMed

    Ren, Ke; Zhou, Xing; Wu, SuJia; Sun, Xiaoliang

    2014-01-01

    Hemangiopericytoma (HPC) is a rare tumor of the central nervous system, most commonly found in the cranial cavity. HPCs in the spine are rare, and very few of them are primary osseous HPC. The aims of this study were to describe a rare case of primary osseous HPC in the thoracic spine and review the literature. A 54-year-old man presented with a 3-month history of back pain. Aneuro logical examination revealed no motor or sensory deficits. Magnetic resonance imaging (MRI) and computed tomography (CT) scan showed a tumor originating from the bone structure of the T10 vertebra with paravertebral extension, and chest CT revealed pulmonary metastases. A laminectomy, face-totomy,and subtotal resection of the tumor was performed with posterior pedicle screw system fixation followed by radiotherapy. The post-operative course was uneventful. His back pain was resolved completely after surgery. The patient survived with tumor during the 18-month follow-up period. Histopathology and immunohistologic findings were consistent with HPC. On immunohistochemistry, the tumor was positive for vimentin and CD34, partially positive for S-100, but negative for EMA, desmin, CD117, and CD1a. A literature review identified eight such cases reported between 1942 and 2013. As a conclusion, clinical manifestations of primary osseous spinal HPCs are different from intraspinal meningeal HPCs. Although showing certain variability, histopathology and immunohistochemical examinations are essential to establish the diagnosis. Surgical resection and radiotherapy are the treatment of choice. *These authors contributed equally to this work.

  18. Osteosarcoma of the mobile spine.

    PubMed

    Zils, K; Bielack, S; Wilhelm, M; Werner, M; Schwarz, R; Windhager, R; Hofmann-Wackersreuther, G; Andus, T; Kager, L; Kuehne, T; Reichardt, P; von Kalle, T

    2013-08-01

    The aims of this analysis were to investigate features and outcome of high-grade osteosarcomas of the mobile spine. Since 1977, 20 Cooperative Osteosarcoma Study Group patients had a diagnosis of high-grade osteosarcomas of the mobile spine and were included in this retrospective analysis of patient-, tumor- and treatment-related variables and outcome. The median age was 29 years (range 5-58). Most frequent tumor sites were thoracic and lumbar spine. All but three patients had nonmetastatic disease at diagnosis. Treatment included surgery and chemotherapy for all patients, 13 were also irradiated. Eight patients failed to achieve a macroscopically complete surgical remission (five local, one primary metastases, two both), six died, two are alive, both with radiotherapy. Of 12 patients with complete remission at all sites, three had a recurrence (two local, one metastases) and died. The median follow-up of the 11 survivors was 8.7 years (range 3.1-22.3), 5-year overall and event-free survival rates were 60% and 43%. Age <40 years, nonmetastatic disease at diagnosis and complete remission predicted for better overall survival (OS, P < 0.05). Osteosarcomas of the mobile spine are rare. With complete resection (and potentially radiotherapy) and chemotherapy, prognosis may be comparable with that of appendicular osteosarcomas.

  19. Osseous anatomy of the lumbosacral spine in Marfan syndrome.

    PubMed

    Sponseller, P D; Ahn, N U; Ahn, U M; Nallamshetty, L; Rose, P S; Kuszyk, B S; Fishman, E K

    2000-11-01

    This study examines pedicle widths, laminar thicknesses, and scalloping values for lumbosacral spine elements in Marfan volunteers. Comparisons were made between these measurements and norms as well as measurements between Marfan patients with and without dural ectasia. To determine if the lumbosacral vertebral elements are altered in the patient with Marfan syndrome. Several abnormalities have been noted in Marfan lumbar spine, including pedicular attenuation and widened interpediculate distances. This may be due to abnormalities of growth or presence of dural ectasia. Given the large numbers of Marfan patients requiring spinal surgery and the high postoperative failure rate, better understanding of the bony anatomy of Marfan lumbar spine is necessary, especially if use of instrumentation is anticipated. Thirty-two volunteers with Marfan syndrome based on the Ghent criteria underwent spiral computed tomography of the lumbosacral spine. Images were evaluated for dural ectasia, and measurements of pedicle width, laminar thickness, and vertebral scalloping were made. Pedicle widths and laminar thicknesses were significantly smaller in Marfan patients at all levels (P<0.001). Mean pedicle widths at L1-L3 were smaller than the smallest available pedicle screw (5 mm). In Marfan patients with dural ectasia, laminar thickness from L5-S2 and pedicle widths at all lumbar levels were significantly reduced (P<0.01). Vertebral scalloping at S1 was significantly greater in Marfan patients with dural ectasia (P = 0.02). Lumbar pedicle width and laminar thickness are significantly reduced in Marfan individuals. Those with dural ectasia demonstrate increased bony erosion of anterior and posterior elements of lumbosacral spine. Preoperative planning and routine computed tomography scans are recommended when operating on Marfan lumbosacral spine.

  20. Spine SBRT using VMAT

    NASA Astrophysics Data System (ADS)

    Goddard, L.; Bodner, W.; Brodin, N. P.; Garg, M.; Lee, A.; Mani, K.; Tomé, W. A.

    2017-01-01

    Metastases of the spinal column are common amongst cancer patients with approximately 18,000 new cases in North America each year that require urgent treatment. Historically radiation therapy doses have been limited due to the proximity of the spinal cord. However as image guidance and localization techniques have improved it has become possible to deliver higher radiation doses to the tumour whilst sparing the spinal cord. This paper presents some of the techniques undertaken at our center.

  1. Femur fractures should not be considered distracting injuries for cervical spine assessment.

    PubMed

    Dahlquist, Robert T; Fischer, Peter E; Desai, Harsh; Rogers, Amelia; Christmas, A Britton; Gibbs, Michael A; Sing, Ronald F

    2015-12-01

    The National Emergency X-Radiography Utilization Study (NEXUS) clinical decision rule is extremely sensitive for clearance of cervical spine (C-spine) injury in blunt trauma patients with distracting injuries. We sought to determine whether the NEXUS criteria would maintain sensitivity for blunt trauma patients when femur fractures were not considered a distracting injury and an absolute indication for diagnostic imaging. We retrospectively analyzed blunt trauma patients with at least 1 femur fracture who presented to our emergency department as trauma activations from 2009 to 2011 and underwent C-spine injury evaluation. Presence of C-spine injury requiring surgical intervention was evaluated. Of 566 trauma patients included, 77 (13.6%) were younger than 18 years. Cervical spine injury was diagnosed in 53 (9.4%) of 566. A total of 241 patients (42.6%) had positive NEXUS findings in addition to distracting injury; 51 (21.2%) of these had C-spine injuries. Of 325 patients (57.4%) with femur fractures who were otherwise NEXUS negative, only 2 (0.6%) had C-spine injuries (95% confidence interval [CI], 0.2%-2.2%); both were stable and required no operative intervention. Use of NEXUS criteria, excluding femur fracture as an indication for imaging, detected all significant injuries with a sensitivity for any C-spine injury of 96.2% (95% CI, 85.9%-99.3%) and negative predictive value of 99.4% (95% CI, 97.6%-99.9%). In our patient population, all significant C-spine injuries were identified by NEXUS criteria without considering the femur fracture a distracting injury and indication for computed tomographic imaging. Reconsidering femur fracture in this context may decrease radiation exposure and health care expenditure with little risk of missed diagnoses. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. [Frequency of diagnosis of postmenopausal osteoporosis of the spine, distant radius and extravertebral fractures in women with normal body mass, overweight and obesity].

    PubMed

    Popov, A A; Izmozherova, N V; Fominykh, M I; Tagil'tseva, N V; Kozulina, E V; Gavrilova, E I

    2008-01-01

    To assess features and peculiarities of postmenopausal osteoporosis (OP) in women with normal body mass, overweight and obesity. Dual energy X-ray absorptiometry of the lumbal spine (Lunar DPX) and distal radius X-ray absorptiometry (DTX 200) were performed during cross-section study of 730 symptomatic postmenopausal women. OP was diagnosed in 253 (34.7%) women, 30.5% of them had normal body mass, 43.2% had overweight and 26.3% were obese. Among them 227 had atraumatic fractures at the age over 50 years. Obese OP patients had significantly higher frequency of arterial hypertension, chronic heart failure, osteoarthritis and glucose metabolism disorders than osteoporotic patients with normal body mass. Fracture frequency did not differ between groups with normal body mass, overweight and obesity. Excessive body mass did not decrease fracture risk in women with postmenopausal OP.

  3. Rapid time course of action potentials in spines and remote dendrites of mouse visual cortex neurons.

    PubMed

    Holthoff, Knut; Zecevic, Dejan; Konnerth, Arthur

    2010-04-01

    Axonally initiated action potentials back-propagate into spiny dendrites of central mammalian neurons and thereby regulate plasticity at excitatory synapses on individual spines as well as linear and supralinear integration of synaptic inputs along dendritic branches. Thus, the electrical behaviour of individual dendritic spines and terminal dendritic branches is critical for the integrative function of nerve cells. The actual dynamics of action potentials in spines and terminal branches, however, are not entirely clear, mostly because electrode recording from such small structures is not feasible. Additionally, the available membrane potential imaging techniques are limited in their sensitivity and require substantial signal averaging for the detection of electrical events at the spatial scale of individual spines. We made a critical improvement in the voltage-sensitive dye imaging technique to achieve multisite recordings of backpropagating action potentials from individual dendritic spines at a high frame rate. With this approach, we obtained direct evidence that in layer 5 pyramidal neurons from the visual cortex of juvenile mice, the rapid time course of somatic action potentials is preserved throughout all cellular compartments, including dendritic spines and terminal branches of basal and apical dendrites. The rapid time course of the action potential in spines may be a critical determinant for the precise regulation of spike timing-dependent synaptic plasticity within a narrow time window.

  4. [Evaluation of upper cervical spine injury (C1-C2) with computed tomography].

    PubMed

    Siemianowicz, Anna; Baron, Jan; Wawrzynek, Wojciech; Koczy, Bogdan; Kasprowska, Sabina

    2006-01-01

    Cervical spine injuries are common and essential diagnostic problem. Diagnostic imaging is necessary for proper and effective treatment. Helical computed tomography (CT) and plain radiography are the basic diagnostic methods in cervical spine injuries. The purpose of this work was the comparison of CT examination of the upper cervical spine (CI-C2) with patients' clinical state. Twenty four patients (17 men and 7 women) were introduced into the study. The most common cause of cervical spine injuries were car accidents (48.5%). CT examination was performed in all patients. Six patients (25%) had multilevel injury, localized at C1-C2 level and in the lower part of cervical spine. The main pathology diagnosed by CT in the studied group was rotatory subluxation (66.6%). Eight patients (33.3%), with rotatory subluxation did not present any abnormalities in neurological examination performed immediately after the admission to the hospital. C1 and/or C2 fractures were diagnosed in 11 patients (45.8%), in some cases (in 3 patients - 12.5%) they were accompanied by rotatory subluxations. CT examination is the basic technique of diagnostic imaging in a case of cervical spine injuries. It enables quick, accurate and precise evaluation of bone structures and surrounding soft tissues. CT also enables multiplanar imaging and 3-dimentional imaging.

  5. [Cervical spine instability in the surgical patient].

    PubMed

    Barbeito, A; Guerri-Guttenberg, R A

    2014-03-01

    Many congenital and acquired diseases, including trauma, may result in cervical spine instability. Given that airway management is closely related to the movement of the cervical spine, it is important that the anesthesiologist has detailed knowledge of the anatomy, the mechanisms of cervical spine instability, and of the effects that the different airway maneuvers have on the cervical spine. We first review the normal anatomy and biomechanics of the cervical spine in the context of airway management and the concept of cervical spine instability. In the second part, we review the protocols for the management of cervical spine instability in trauma victims and some of the airway management options for these patients. Copyright © 2013 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. All rights reserved.

  6. Aquatic antagonists: cutaneous sea urchin spine injury.

    PubMed

    Hsieh, Clifford; Aronson, Erica R; Ruiz de Luzuriaga, Arlene M

    2016-11-01

    Injuries from sea urchin spines are commonly seen in coastal regions with high levels of participation in water activities. Although these injuries may seem minor, the consequences vary based on the location of the injury. Sea urchin spine injuries may cause arthritis and synovitis from spines in the joints. Nonjoint injuries have been reported, and dermatologic aspects of sea urchin spine injuries rarely have been discussed. We present a case of a patient with sea urchin spines embedded in the thigh who subsequently developed painful skin nodules. Tissue from the site of the injury demonstrated foreign-body type granulomas. Following the removal of the spines and granulomatous tissue, the patient experienced resolution of the nodules and associated pain. Extraction of sea urchin spines can attenuate the pain and decrease the likelihood of granuloma formation, infection, and long-term sequelae.

  7. Cervical Spine Injuries in the Athlete.

    PubMed

    Schroeder, Gregory D; Vaccaro, Alexander R

    2016-09-01

    Cervical spine injuries are extremely common and range from relatively minor injuries, such as cervical muscle strains, to severe, life-threatening cervical fractures with spinal cord injuries. Although cervical spine injuries are most common in athletes who participate in contact and collision sports, such as American football and rugby, they also have been reported in athletes who participate in noncontact sports, such as baseball, gymnastics, and diving. Cervical spine injuries in athletes are not necessarily the result of substantial spine trauma; some athletes have chronic conditions, such as congenital stenosis, that increase their risk for a serious cervical spine injury after even minor trauma. Therefore, physicians who cover athletic events must have a thorough knowledge of cervical spine injures and the most appropriate ways in which they should be managed. Although cervical spine injuries can be career-ending injuries, athletes often are able to return to play after appropriate treatment if the potential for substantial re-injury is minimized.

  8. Traumatic subdural hematoma in the lumbar spine.

    PubMed

    Song, Jenn-Yeu; Chen, Yu-Hao; Hung, Kuang-Chen; Chang, Ti-Sheng

    2011-10-01

    Traumatic spinal subdural hematoma is rare and its mechanism remains unclear. This intervention describes a patient with mental retardation who was suffering from back pain and progressive weakness of the lower limbs following a traffic accident. Magnetic resonance imaging of the spine revealed a lumbar subdural lesion. Hematoma was identified in the spinal subdural space during an operation. The muscle power of both lower limbs recovered to normal after surgery. The isolated traumatic spinal subdural hematoma was not associated with intracranial subdural hemorrhage. A spinal subdural hematoma should be considered in the differential diagnosis of spinal cord compression, especially for patients who have sustained spinal trauma. Emergency surgical decompression is usually the optimal treatment for a spinal subdural hematoma with acute deterioration and severe neurological deficits. Copyright © 2011. Published by Elsevier B.V.

  9. Sensitivity of MRI of the spine compared with CT myelography in orthostatic headache with CSF leak.

    PubMed

    Starling, Amaal; Hernandez, Fatima; Hoxworth, Joseph M; Trentman, Terrence; Halker, Rashmi; Vargas, Bert B; Hastriter, Eric; Dodick, David

    2013-11-12

    To investigate the sensitivity of MRI of the spine compared with CT myelography (CTM) in detecting CSF leaks. Between July 1998 and October 2010, 12 patients with orthostatic headache and a CTM-confirmed spinal CSF leak underwent an MRI of the spine with and without contrast. Using CTM as the gold standard, we retrospectively investigated the sensitivity of spinal MRI in detecting a CSF leak. Eleven of 12 patients with a CSF leak documented by CTM also had extradural fluid collections on spinal MRI (sensitivity 91.7%). Six patients with extradural fluid collections on spinal MRI also had spinal dural enhancement. When compared with the gold standard of CTM, MRI of the spine appears to be a sensitive and less invasive imaging modality for detecting a spinal CSF leak, suggesting that MRI of the spine should be the imaging modality of first choice for the detection of spinal CSF leaks.

  10. Effect of once-yearly zoledronic acid on the spine and hip as measured by quantitative computed tomography: results of the HORIZON Pivotal Fracture Trial

    PubMed Central

    Lang, T.; Boonen, S.; Cummings, S.; Delmas, P. D.; Cauley, J. A.; Horowitz, Z.; Kerzberg, E.; Bianchi, G.; Kendler, D.; Leung, P.; Man, Z.; Mesenbrink, P.; Eriksen, E. F.; Black, D. M.

    2016-01-01

    Summary Changes in bone mineral density and bone strength following treatment with zoledronic acid (ZOL) were measured by quantitative computed analysis (QCT) or dual-energy X-ray absorptiometry (DXA). ZOL treatment increased spine and hip BMD vs placebo, assessed by QCT and DXA. Changes in trabecular bone resulted in increased bone strength. Introduction To investigate bone mineral density (BMD) changes in trabecular and cortical bone, estimated by quantitative computed analysis (QCT) or dual-energy X-ray absorptiometry (DXA), and whether zoledronic acid 5 mg (ZOL) affects bone strength. Methods In 233 women from a randomized, controlled trial of once-yearly ZOL, lumbar spine, total hip, femoral neck, and trochanter were assessed by DXA and QCT (baseline, Month 36). Mean percentage changes from baseline and between-treatment differences (ZOL vs placebo, t-test) were evaluated. Results Mean between-treatment differences for lumbar spine BMD were significant by DXA (7.0%, p<0.01) and QCT (5.7%, p<0.0001). Between-treatment differences were significant for trabecular spine (p=0.0017) [non-parametric test], trabecular trochanter (10.7%, p<0.0001), total hip (10.8%, p<0.0001), and compressive strength indices at femoral neck (8.6%, p=0.0001), and trochanter (14.1%, p<0.0001). Conclusions Once-yearly ZOL increased hip and spine BMD vs placebo, assessed by QCT vs DXA. Changes in trabecular bone resulted in increased indices of compressive strength. PMID:19802508

  11. Non-Ionotropic NMDA Receptor Signaling Drives Activity-Induced Dendritic Spine Shrinkage.

    PubMed

    Stein, Ivar S; Gray, John A; Zito, Karen

    2015-09-02

    The elimination of dendritic spine synapses is a critical step in the refinement of neuronal circuits during development of the cerebral cortex. Several studies have shown that activity-induced shrinkage and retraction of dendritic spines depend on activation of the NMDA-type glutamate receptor (NMDAR), which leads to influx of extracellular calcium ions and activation of calcium-dependent phosphatases that modify regulators of the spine cytoskeleton, suggesting that influx of extracellular calcium ions drives spine shrinkage. Intriguingly, a recent report revealed a novel non-ionotropic function of the NMDAR in the regulation of synaptic strength, which relies on glutamate binding but is independent of ion flux through the receptor (Nabavi et al., 2013). Here, we tested whether non-ionotropic NMDAR signaling could also play a role in driving structural plasticity of dendritic spines. Using two-photon glutamate uncaging and time-lapse imaging of rat hippocampal CA1 neurons, we show that low-frequency glutamatergic stimulation results in shrinkage of dendritic spines even in the presence of the NMDAR d-serine/glycine binding site antagonist 7-chlorokynurenic acid (7CK), which fully blocks NMDAR-mediated currents and Ca(2+) transients. Notably, application of 7CK or MK-801 also converts spine enlargement resulting from a high-frequency uncaging stimulus into spine shrinkage, demonstrating that strong Ca(2+) influx through the NMDAR normally overcomes a non-ionotropic shrinkage signal to drive spine growth. Our results support a model in which NMDAR signaling, independent of ion flux, drives structural shrinkage at spiny synapses. Dendritic spine elimination is vital for the refinement of neural circuits during development and has been linked to improvements in behavioral performance in the adult. Spine shrinkage and elimination have been widely accepted to depend on Ca(2+) influx through NMDA-type glutamate receptors (NMDARs) in conjunction with long-term depression

  12. Aspergillus spondylitis involving the cervico-thoraco-lumbar spine in an immunocompromised patient: a case report.

    PubMed

    Son, Jeong-Min; Jee, Won-Hee; Jung, Chan-Kwon; Kim, Sang-Il; Ha, Kee-Yong

    2007-01-01

    Aspergillosis is a rare cause of spondylitis. Moreover, early diagnosis by MR imaging and adequate treatment can prevent the serious complications of fungal infection. To our knowledge, the MR findings of multilevel aspergillus spondylitis in the cervico-thoraco-lumbar spine have not been previously described. Here, we report the MR findings of aspergillus spondylitis involving the cervical, thoracic, and lumbar spine in a liver transplant recipient.

  13. Aspergillus Spondylitis involving the Cervico-Thoraco-Lumbar Spine in an Immunocompromised Patient: a Case Report

    PubMed Central

    Son, Jeong-Min; Jung, Chan-Kwon; Kim, Sang-Il; Ha, Kee-Yong

    2007-01-01

    Aspergillosis is a rare cause of spondylitis. Moreover, early diagnosis by MR imaging and adequate treatment can prevent the serious complications of fungal infection. To our knowledge, the MR findings of multilevel aspergillus spondylitis in the cervico-thoraco-lumbar spine have not been previously described. Here, we report the MR findings of aspergillus spondylitis involving the cervical, thoracic, and lumbar spine in a liver transplant recipient. PMID:17923789

  14. Spines of the porcupine fish: Structure, composition, and mechanical properties.

    PubMed

    Su, Frances Y; Bushong, Eric A; Deerinck, Thomas J; Seo, Kyungah; Herrera, Steven; Graeve, Olivia A; Kisailus, David; Lubarda, Vlado A; McKittrick, Joanna

    2017-09-01

    This paper explores the structure, composition, and mechanical properties of porcupine fish spines for the first time. The spine was found to be composed of nanocrystalline hydroxyapatite, protein (collagen), and water using X-ray diffraction, energy-dispersive X-ray spectroscopy, and thermogravimetric analysis. Microstructures have mineralized fibrillar sheets in the longitudinal direction and in a radial orientation in the transverse direction that were observed using light and electron microscopy. Based on the images, the hierarchical structure of the spine shows both concentric and radial reinforcement. Mechanical properties were obtained using cantilever beam and nanoindentation tests. A tapered cantilever beam model was developed and compared to that of a uniform cantilever beam. The tapered beam model showed that while the stresses experienced were similar to those of the uniform beam, the location of the maximum stress was near the distal region of the beam rather than at the base, which allows the porcupine fish to conserve energy and resources if the spine is fractured. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Use of iDXA spine scans to evaluate total and visceral abdominal fat.

    PubMed

    Bea, J W; Hsu, C-H; Blew, R M; Irving, A P; Caan, B J; Kwan, M L; Abraham, I; Going, S B

    2018-01-01

    Abdominal fat may be a better predictor than body mass index (BMI) for risk of metabolically-related diseases, such as diabetes, cardiovascular disease, and some cancers. We sought to validate the percent fat reported on dual energy X-ray absorptiometry (DXA) regional spine scans (spine fat fraction, SFF) against abdominal fat obtained from total body scans using the iDXA machine (General Electric, Madison, WI), as previously done on the Prodigy model. Total body scans and regional spine scans were completed on the same day (N = 50). In alignment with the Prodigy-based study, the following regions of interest (ROI) were assessed from total body scans and compared to the SFF from regional spine scans: total abdominal fat at (1) lumbar vertebrae L2-L4 and (2) L2-Iliac Crest (L2-IC); (3) total trunk fat; and (4) visceral fat in the android region. Separate linear regression models were used to predict each total body scan ROI from SFF; models were validated by bootstrapping. The sample was 84% female, a mean age of 38.5 ± 17.4 years, and mean BMI of 23.0 ± 3.8 kg/m 2 . The SFF, adjusted for BMI, predicted L2-L4 and L2-IC total abdominal fat (%; Adj. R 2 : 0.90) and total trunk fat (%; Adj. R 2 : 0.88) well; visceral fat (%) adjusted R 2 was 0.83. Linear regression models adjusted for additional participant characteristics resulted in similar adjusted R 2 values. This replication of the strong correlation between SFF and abdominal fat measures on the iDXA in a new population confirms the previous Prodigy model findings and improves generalizability. © 2017 Wiley Periodicals, Inc.

  16. Correlation between degenerative spine disease and bone marrow density: a retrospective investigation.

    PubMed

    Grams, Astrid Ellen; Rehwald, Rafael; Bartsch, Alexander; Honold, Sarah; Freyschlag, Christian Franz; Knoflach, Michael; Gizewski, Elke Ruth; Glodny, Bernhard

    2016-02-24

    Spondylosis leads to an overestimation of bone mineral density (BMD) with dual-energy x-ray absorptiometry (DXA) but not with quantitative computed tomography (QCT). The correlation between degenerative changes of the spine and QCT-BMD was therefore investigated for the first time. One hundred thirty-four patients (66 female and 68 male) with a mean age of 49.0 ± 14.6 years (range: 19-88 years) who received a CT scan and QCT-BMD measurements of spine and hip were evaluated retrospectively. The occurrence and severity of spondylosis, osteochondrosis, and spondylarthrosis and the height of the vertebral bodies were assessed. A negative correlation was found between spinal BMD and number of spondylophytes (ρ = -0.35; p < 0.01), disc heights (r = -0.33; p < 0.01), number of discal air inclusions (ρ = -0.34; p < 0.01), the number of Schmorl nodules (ρ = -0.25; p < 0.01), the number (ρ = -0.219; p < 0.05) and the degree (ρ = -0.220; p < 0.05) of spondylarthrosis. Spinal and hip BMD correlated moderately, but the latter did not correlate with degenerative changes of the spine. In linear regression models age, osteochondrosis and spondylarthrosis were factors influencing spinal BMD. Degenerative spinal changes may be associated with reduced regional spinal mineralization. This knowledge could lead to a modification of treatment of degenerative spine disease with early treatment of osteopenia to prevent secondary fractures.

  17. Osteoradionecrosis of the subaxial cervical spine following treatment for head and neck carcinomas.

    PubMed

    Khorsandi, A S; Su, H K; Mourad, W F; Urken, M L; Persky, M S; Lazarus, C L; Jacobson, A S

    2015-01-01

    To study MRI and positron emission tomography (PET)/CT imaging of osteoradionecrosis (ORN) of the subaxial cervical spine, a serious long-term complication of radiation therapy (RT) for head and neck cancers that can lead to pain, vertebral instability, myelopathy and cord compression. This is a single-institution retrospective review of patients diagnosed and treated for ORN of the subaxial cervical spine following surgery and radiation for head and neck cancer. We report PET/CT imaging and MRI for four patients, each with extensive treatment for recurrent head and neck cancer. Osteomyelitis (OM) and discitis are the end-stage manifestations of ORN of the subaxial spine. ORN of the subaxial spine has variable imaging appearance and needs to be differentiated from recurrent or metastatic disease. Surgical violation of the posterior pharyngeal wall on top of the compromised vasculature in patients treated heavily with RT may pre-dispose the subaxial cervical vertebrae to ORN, with possible resultant OM and discitis. MRI and PET/CT imaging are complimentary in this setting. PET/CT images may be misinterpreted in view of the history of head and neck cancer. MRI should be utilized for definitive diagnosis of OM and discitis in view of its imaging specificity. We identify the end-stage manifestation of ORN in the sub-axial spine on PET/CT and MRI to facilitate its correct diagnosis.

  18. Computational Growth and Remodeling of Abdominal Aortic Aneurysms Constrained by the Spine

    PubMed Central

    Farsad, Mehdi; Zeinali-Davarani, Shahrokh; Choi, Jongeun; Baek, Seungik

    2015-01-01

    Abdominal aortic aneurysms (AAAs) evolve over time, and the vertebral column, which acts as an external barrier, affects their biomechanical properties. Mechanical interaction between AAAs and the spine is believed to alter the geometry, wall stress distribution, and blood flow, although the degree of this interaction may depend on AAAs specific configurations. In this study, we use a growth and remodeling (G&R) model, which is able to trace alterations of the geometry, thus allowing us to computationally investigate the effect of the spine for progression of the AAA. Medical image-based geometry of an aorta is constructed along with the spine surface, which is incorporated into the computational model as a cloud of points. The G&R simulation is initiated by local elastin degradation with different spatial distributions. The AAA–spine interaction is accounted for using a penalty method when the AAA surface meets the spine surface. The simulation results show that, while the radial growth of the AAA wall is prevented on the posterior side due to the spine acting as a constraint, the AAA expands faster on the anterior side, leading to higher curvature and asymmetry in the AAA configuration compared to the simulation excluding the spine. Accordingly, the AAA wall stress increases on the lateral, posterolateral, and the shoulder regions of the anterior side due to the AAA–spine contact. In addition, more collagen is deposited on the regions with a maximum diameter. We show that an image-based computational G&R model not only enhances the prediction of the geometry, wall stress, and strength distributions of AAAs but also provides a framework to account for the interactions between an enlarging AAA and the spine for a better rupture potential assessment and management of AAA patients. PMID:26158885

  19. Computational Growth and Remodeling of Abdominal Aortic Aneurysms Constrained by the Spine.

    PubMed

    Farsad, Mehdi; Zeinali-Davarani, Shahrokh; Choi, Jongeun; Baek, Seungik

    2015-09-01

    Abdominal aortic aneurysms (AAAs) evolve over time, and the vertebral column, which acts as an external barrier, affects their biomechanical properties. Mechanical interaction between AAAs and the spine is believed to alter the geometry, wall stress distribution, and blood flow, although the degree of this interaction may depend on AAAs specific configurations. In this study, we use a growth and remodeling (G&R) model, which is able to trace alterations of the geometry, thus allowing us to computationally investigate the effect of the spine for progression of the AAA. Medical image-based geometry of an aorta is constructed along with the spine surface, which is incorporated into the computational model as a cloud of points. The G&R simulation is initiated by local elastin degradation with different spatial distributions. The AAA-spine interaction is accounted for using a penalty method when the AAA surface meets the spine surface. The simulation results show that, while the radial growth of the AAA wall is prevented on the posterior side due to the spine acting as a constraint, the AAA expands faster on the anterior side, leading to higher curvature and asymmetry in the AAA configuration compared to the simulation excluding the spine. Accordingly, the AAA wall stress increases on the lateral, posterolateral, and the shoulder regions of the anterior side due to the AAA-spine contact. In addition, more collagen is deposited on the regions with a maximum diameter. We show that an image-based computational G&R model not only enhances the prediction of the geometry, wall stress, and strength distributions of AAAs but also provides a framework to account for the interactions between an enlarging AAA and the spine for a better rupture potential assessment and management of AAA patients.

  20. Effects of whole spine alignment patterns on neck responses in rear end impact.

    PubMed

    Sato, Fusako; Odani, Mamiko; Miyazaki, Yusuke; Yamazaki, Kunio; Östh, Jonas; Svensson, Mats

    2017-02-17

    The aim of this study was to investigate the whole spine alignment in automotive seated postures for both genders and the effects of the spinal alignment patterns on cervical vertebral motion in rear impact using a human finite element (FE) model. Image data for 8 female and 7 male subjects in a seated posture acquired by an upright open magnetic resonance imaging (MRI) system were utilized. Spinal alignment was determined from the centers of the vertebrae and average spinal alignment patterns for both genders were estimated by multidimensional scaling (MDS). An occupant FE model of female average size (162 cm, 62 kg; the AF 50 size model) was developed by scaling THUMS AF 05. The average spinal alignment pattern for females was implemented in the model, and model validation was made with respect to female volunteer sled test data from rear end impacts. Thereafter, the average spinal alignment pattern for males and representative spinal alignments for all subjects were implemented in the validated female model, and additional FE simulations of the sled test were conducted to investigate effects of spinal alignment patterns on cervical vertebral motion. The estimated average spinal alignment pattern was slight kyphotic, or almost straight cervical and less-kyphotic thoracic spine for the females and lordotic cervical and more pronounced kyphotic thoracic spine for the males. The AF 50 size model with the female average spinal alignment exhibited spine straightening from upper thoracic vertebra level and showed larger intervertebral angular displacements in the cervical spine than the one with the male average spinal alignment. The cervical spine alignment is continuous with the thoracic spine, and a trend of the relationship between cervical spine and thoracic spinal alignment was shown in this study. Simulation results suggested that variations in thoracic spinal alignment had a potential impact on cervical spine motion as well as cervical spinal alignment in rear

  1. Bone geometry, structure and mineral distribution using Dual energy X ray Absorptiometry (DXA)

    NASA Technical Reports Server (NTRS)

    Whalen, Robert; Cleek, Tammy

    1993-01-01

    Dual energy x-ray absorptiometry (DXA) is currently the most widely used method of analyzing regional and whole body changes in bone mineral content (BMC) and areal (g/sq cm) bone mineral density (BMD). However, BMC and BMD do not provide direct measures of long bone geometry, structure, or strength nor do regional measurements detect localized changes in other regions of the same bone. The capabilities of DXA can be enhanced significantly by special processing of pixel BMC data which yields cross-sectional geometric and structural information. We have extended this method of analysis in order to develop non-uniform structural beam models of long bones.

  2. Method and apparatus for multiple-projection, dual-energy x-ray absorptiometry scanning

    NASA Technical Reports Server (NTRS)

    Feldmesser, Howard S. (Inventor); Magee, Thomas C. (Inventor); Charles, Jr., Harry K. (Inventor); Beck, Thomas J. (Inventor)

    2007-01-01

    Methods and apparatuses for advanced, multiple-projection, dual-energy X-ray absorptiometry scanning systems include combinations of a conical collimator; a high-resolution two-dimensional detector; a portable, power-capped, variable-exposure-time power supply; an exposure-time control element; calibration monitoring; a three-dimensional anti-scatter-grid; and a gantry-gantry base assembly that permits up to seven projection angles for overlapping beams. Such systems are capable of high precision bone structure measurements that can support three dimensional bone modeling and derivations of bone strength, risk of injury, and efficacy of countermeasures among other properties.

  3. Performance Indicators in Spine Surgery.

    PubMed

    St-Pierre, Godefroy Hardy; Yang, Michael H; Bourget-Murray, Jonathan; Thomas, Ken C; Hurlbert, Robin John; Matthes, Nikolas

    2018-02-15

    Systematic review. To elucidate how performance indicators are currently used in spine surgery. The Patient Protection and Affordable Care Act has given significant traction to the idea that healthcare must provide value to the patient through the introduction of hospital value-based purchasing. The key to implementing this new paradigm is to measure this value notably through performance indicators. MEDLINE, CINAHL Plus, EMBASE, and Google Scholar were searched for studies reporting the use of performance indicators specific to spine surgery. We followed the Prisma-P methodology for a systematic review for entries from January 1980 to July 2016. All full text articles were then reviewed to identify any measure of performance published within the article. This measure was then examined as per the three criteria of established standard, exclusion/risk adjustment, and benchmarking to determine if it constituted a performance indicator. The initial search yielded 85 results among which two relevant studies were identified. The extended search gave a total of 865 citations across databases among which 15 new articles were identified. The grey literature search provided five additional reports which in turn led to six additional articles. A total of 27 full text articles and reports were retrieved and reviewed. We were unable to identify performance indicators. The articles presenting a measure of performance were organized based on how many criteria they lacked. We further examined the next steps to be taken to craft the first performance indicator in spine surgery. The science of performance measurement applied to spine surgery is still in its infancy. Current outcome metrics used in clinical settings require refinement to become performance indicators. Current registry work is providing the necessary foundation, but requires benchmarking to truly measure performance. 1.

  4. RSA in Spine: A Review.

    PubMed

    Humadi, Ali; Dawood, Sulaf; Halldin, Klas; Freeman, Brian

    2017-12-01

    Systematic review of literature. This systematic review was conducted to investigate the accuracy of radiostereometric analysis (RSA), its assessment of spinal motion and disorders, and to investigate the limitations of this technique in spine assessment. Systematic review in all current literature to invesigate the role of RSA in spine. The results of this review concluded that RSA is a very powerful tool to detect small changes between 2 rigid bodies such as a vertebral segment. The technique is described for animal and human studies for cervical and lumbar spine and can be used to analyze range of motion, inducible displacement, and fusion of segments. However, there are a few disadvantages with the technique; RSA percutaneous procedure needs to be performed to implant the markers (and cannot be used preoperatively), one needs a specific knowledge to handle data and interpret the results, and is relatively time consuming and expensive. RSA should be looked at as a very powerful research instrument and there are many questions suitable for RSA studies.

  5. RSA in Spine: A Review

    PubMed Central

    Dawood, Sulaf; Halldin, Klas; Freeman, Brian

    2017-01-01

    Study Design: Systematic review of literature. Objectives: This systematic review was conducted to investigate the accuracy of radiostereometric analysis (RSA), its assessment of spinal motion and disorders, and to investigate the limitations of this technique in spine assessment. Methods: Systematic review in all current literature to invesigate the role of RSA in spine. Results: The results of this review concluded that RSA is a very powerful tool to detect small changes between 2 rigid bodies such as a vertebral segment. The technique is described for animal and human studies for cervical and lumbar spine and can be used to analyze range of motion, inducible displacement, and fusion of segments. However, there are a few disadvantages with the technique; RSA percutaneous procedure needs to be performed to implant the markers (and cannot be used preoperatively), one needs a specific knowledge to handle data and interpret the results, and is relatively time consuming and expensive. Conclusions: RSA should be looked at as a very powerful research instrument and there are many questions suitable for RSA studies. PMID:29238647

  6. Maxillofacial trauma - Underestimation of cervical spine injury.

    PubMed

    Reich, Waldemar; Surov, Alexey; Eckert, Alexander Walter

    2016-09-01

    Undiagnosed cervical spine injury can have devastating results. The aim of this study was to analyse patients with primary maxillofacial trauma and a concomitant cervical spine injury. It is hypothetised that cervical spine injury is predictable in maxillofacial surgery. A monocentric clinical study was conducted over a 10-year period to analyse patients with primary maxillofacial and associated cervical spine injuries. Demographic data, mechanism of injury, specific trauma and treatments provided were reviewed. Additionally a search of relevant international literature was conducted in PubMed by terms "maxillofacial" AND "cervical spine" AND "injury". Of 3956 patients, n = 3732 (94.3%) suffered from craniomaxillofacial injuries only, n = 174 (4.4%) from cervical spine injuries only, and n = 50 (1.3%) from both craniomaxillofacial and cervical spine injuries. In this study cohort the most prevalent craniofacial injuries were: n = 41 (44%) midfacial and n = 21 (22.6%) skull base fractures. Cervical spine injuries primarily affected the upper cervical spine column: n = 39 (58.2%) vs. n = 28 (41.8%). Only in 3 of 50 cases (6%), the cervical spine injury was diagnosed coincidentally, and the cervical spine column was under immobilised. The operative treatment rate for maxillofacial injuries was 36% (n = 18), and for cervical spine injuries 20% (n = 10). The overall mortality rate was 8% (n = 4). The literature search yielded only 12 papers (11 retrospective and monocentric cohort studies) and is discussed before our own results. In cases of apparently isolated maxillofacial trauma, maxillofacial surgeons should be aware of a low but serious risk of underestimating an unstable cervical spine injury. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  7. Cervical Spine Clearance in Pediatric Trauma Centers: The Need for Standardization and an Evidence-based Protocol.

    PubMed

    Pannu, Gurpal S; Shah, Mitesh P; Herman, Marty J

    Cervical spine clearance in the pediatric trauma patient represents a particularly challenging task. Unfortunately, standardized clearance protocols for pediatric cervical clearance are poorly reported in the literature and imaging recommendations demonstrate considerable variability. With the use of a web-based survey, this study aims to define the methods utilized by pediatric trauma centers throughout North America. Specific attention was given to the identification of personnel responsible for cervical spine care, diagnostic imaging modalities used, and the presence or absence of a written pediatric cervical spine clearance protocol. A 10-question electronic survey was given to members of the newly formed Pediatric Cervical Spine Study Group, all of whom are active POSNA members. The survey was submitted via the online service SurveyMonkey (https://www.surveymonkey.com/r/7NVVQZR). The survey assessed the respondent's institution demographics, such as trauma level and services primarily responsible for consultation and operative management of cervical spine injuries. In addition, respondents were asked to identify the protocols and primary imaging modality used for cervical spine clearance. Finally, respondents were asked if their institution had a documented cervical spine clearance protocol. Of the 25 separate institutions evaluated, 21 were designated as level 1 trauma centers. Considerable variation was reported with regards to the primary service responsible for cervical spine clearance. General Surgery/Trauma (44%) is most commonly the primary service, followed by a rotating schedule (33%), Neurosugery (11%), and Orthopaedic Surgery (8%). Spine consults tend to be seen most commonly by a rotating schedule of Orthopaedic Surgery and Neurosurgery. The majority of responding institutions utilize computed tomographic imaging (46%) as the primary imaging modality, whereas 42% of hospitals used x-ray primarily. The remaining institutions reported using a

  8. A model of activity-dependent changes in dendritic spine density and spine structure.

    PubMed

    Crook, S M; Dur-E-Ahmad, M; Baer, S M

    2007-10-01

    Recent evidence indicates that the morphology and density of dendritic spines are regulated during synaptic plasticity. See, for instance, a review by Hayashi and Majewska [9]. In this work, we extend previous modeling studies [27] by combining a model for activity-dependent spine density with one for calcium-mediated spine stem restructuring. The model is based on the standard dimensionless cable equation, which represents the change in the membrane potential in a passive dendrite. Additional equations characterize the change in spine density along the dendrite, the current balance equation for an individual spine head, the change in calcium concentration in the spine head, and the dynamics of spine stem resistance. We use computational studies to investigate the changes in spine density and structure for differing synaptic inputs and demonstrate the effects of these changes on the input-output properties of the dendritic branch. Moderate amounts of high-frequency synaptic activation to dendritic spines result in an increase in spine stem resistance that is correlated with spine stem elongation. In addition, the spine density increases both inside and outside the input region. The model is formulated so that this long-term potentiation-inducing stimulus eventually leads to structural stability. In contrast, a prolonged low-frequency stimulation paradigm that would typically induce long-term depression results in a decrease in stem resistance (correlated with stem shortening) and an eventual decrease in spine density.

  9. Microscope sterility during spine surgery.

    PubMed

    Bible, Jesse E; O'Neill, Kevin R; Crosby, Colin G; Schoenecker, Jonathan G; McGirt, Matthew J; Devin, Clinton J

    2012-04-01

    Prospective study. Assess the contamination rates of sterile microscope drapes after spine surgery. The use of the operating microscope has become more prevalent in certain spine procedures, providing superior magnification, visualization, and illumination of the operative field. However, it may represent an additional source of bacterial contamination and increase the risk of developing a postoperative infection. This study included 25 surgical spine cases performed by a single spine surgeon that required the use of the operative microscope. Sterile culture swabs were used to obtain samples from 7 defined locations on the microscope drape after its use during the operation. The undraped technician's console was sampled in each case as a positive control, and an additional 25 microscope drapes were swabbed immediately after they were applied to the microscope to obtain negative controls. Swab samples were assessed for bacterial growth on 5% sheep blood Columbia agar plates using a semiquantitative technique. No growth was observed on any of the 25 negative control drapes. In contrast, 100% of preoperative and 96% of postoperative positive controls demonstrated obvious contamination. In the postoperative group, all 7 sites of evaluation were found to be contaminated with rates of 12% to 44%. Four of the 7 evaluated locations were found to have significant contamination rates compared with negative controls, including the shafts of the optic eyepieces on the main surgeon side (24%, P = 0.022), "forehead" portion on both the main surgeon (24%, P = 0.022) and assistant sides (28%, P = 0.010), and "overhead" portion of the drape (44%, P = 0.0002). Bacterial contamination of the operative microscope was found to be significant after spine surgery. Contamination was more common around the optic eyepieces, likely due to inadvertent touching of unsterile portions. Similarly, all regions above the eyepieces also have a propensity for contamination because of unknown contact

  10. Spines slow down dendritic chloride diffusion and affect short-term ionic plasticity of GABAergic inhibition

    NASA Astrophysics Data System (ADS)

    Mohapatra, Namrata; Tønnesen, Jan; Vlachos, Andreas; Kuner, Thomas; Deller, Thomas; Nägerl, U. Valentin; Santamaria, Fidel; Jedlicka, Peter

    2016-03-01

    Cl- plays a crucial role in neuronal function and synaptic inhibition. However, the impact of neuronal morphology on the diffusion and redistribution of intracellular Cl- is not well understood. The role of spines in Cl- diffusion along dendritic trees has not been addressed so far. Because measuring fast and spatially restricted Cl- changes within dendrites is not yet technically possible, we used computational approaches to predict the effects of spines on Cl- dynamics in morphologically complex dendrites. In all morphologies tested, including dendrites imaged by super-resolution STED microscopy in live brain tissue, spines slowed down longitudinal Cl- diffusion along dendrites. This effect was robust and could be observed in both deterministic as well as stochastic simulations. Cl- extrusion altered Cl- diffusion to a much lesser extent than the presence of spines. The spine-dependent slowing of Cl- diffusion affected the amount and spatial spread of changes in the GABA reversal potential thereby altering homosynaptic as well as heterosynaptic short-term ionic plasticity at GABAergic synapses in dendrites. Altogether, our results suggest a fundamental role of dendritic spines in shaping Cl- diffusion, which could be of relevance in the context of pathological conditions where spine densities and neural excitability are perturbed.

  11. Lumbar spine disc heights and curvature: upright posture vs. supine compression harness

    NASA Technical Reports Server (NTRS)

    Lee, Shi-Uk; Hargens, Alan R.; Fredericson, Michael; Lang, Philipp K.

    2003-01-01

    INTRODUCTION: Spinal lengthening in microgravity is thought to cause back pain in astronauts. A spinal compression harness can compress the spine to eliminate lengthening but the loading condition with harness is different than physiologic conditions. Our purpose was to compare the effect of spine compression with a harness in supine position on disk height and spinal curvature in the lumbar spine to that of upright position as measured using a vertically open magnetic resonance imaging system. METHODS: Fifteen healthy subjects volunteered. On day 1, each subject lay supine for an hour and a baseline scan of the lumbar spine was performed. After applying a load of fifty percent of body weight with the harness for thirty minutes, the lumbar spine was scanned again. On day 2, after a baseline scan, a follow up scan was performed after kneeling for thirty minutes within the gap between two vertically oriented magnetic coils. Anterior and posterior disk heights, posterior disk bulging, and spinal curvature were measured from the baseline and follow up scans. RESULTS: Anterior disk heights increased and posterior disk heights decreased compared with baseline scans both after spinal compression with harness and upright posture. The spinal curvature increased by both loading conditions of the spine. DISCUSSION: The spinal compression with specially designed harness has the same effect as the physiologic loading of the spine in the kneeling upright position. The harness shows some promise as a tool to increase the diagnostic capabilities of a conventional MR system.

  12. Evidence basis for management of spine and chest wall deformities in children.

    PubMed

    Sponseller, Paul D; Yazici, Muharrem; Demetracopoulos, Constantine; Emans, John B

    2007-09-01

    : Review of relevant studies, including levels of evidence. : To review research on growth of the spine and chest wall and treatment of deformities. To place this knowledge in context of evidence-based assessment. : Knowledge of the growth of the spine, chest wall, and lung in the normal and deformity states has evolved among independent specialties over the past 60 years. Interest in the interrelationship has blossomed as more tools for assessment and treatment have developed. Spine-based and chest wall-based treatment options now exist, as well as options of resection versus gradual distraction. : Peer-reviewed research published on the growth of the spine, lung, chest wall, and treatment of their deformities was reviewed. Treatment methods and outcomes were compared. Ranking of the levels of evidence was performed where possible. : Most studies of these topics are Level III and IV studies, consisting of case-control studies and case series. This limitation arises because of the rarity and heterogeneity of the disorders affecting the growing spine and chest wall. The natural history of most types of spinal/chest wall deformities is not known with accuracy. Some experimental evidence informs the treatments which involve modulation of the growth of the spine. However, accurate models of the deformities themselves are lacking. Improvements in imaging and measurement offer options for more accurate patient comparison. : The natural history and results of treatment of deformities of the spine and chest wall offer much opportunity for further evidence-based research.

  13. Mechanical coupling between transsynaptic N-cadherin adhesions and actin flow stabilizes dendritic spines

    PubMed Central

    Chazeau, Anaël; Garcia, Mikael; Czöndör, Katalin; Perrais, David; Tessier, Béatrice; Giannone, Grégory; Thoumine, Olivier

    2015-01-01

    The morphology of neuronal dendritic spines is a critical indicator of synaptic function. It is regulated by several factors, including the intracellular actin/myosin cytoskeleton and transcellular N-cadherin adhesions. To examine the mechanical relationship between these molecular components, we performed quantitative live-imaging experiments in primary hippocampal neurons. We found that actin turnover and structural motility were lower in dendritic spines than in immature filopodia and increased upon expression of a nonadhesive N-cadherin mutant, resulting in an inverse relationship between spine motility and actin enrichment. Furthermore, the pharmacological stimulation of myosin II induced the rearward motion of actin structures in spines, showing that myosin II exerts tension on the actin network. Strikingly, the formation of stable, spine-like structures enriched in actin was induced at contacts between dendritic filopodia and N-cadherin–coated beads or micropatterns. Finally, computer simulations of actin dynamics mimicked various experimental conditions, pointing to the actin flow rate as an important parameter controlling actin enrichment in dendritic spines. Together these data demonstrate that a clutch-like mechanism between N-cadherin adhesions and the actin flow underlies the stabilization of dendritic filopodia into mature spines, a mechanism that may have important implications in synapse initiation, maturation, and plasticity in the developing brain. PMID:25568337

  14. Dendritic spine instability and insensitivity to modulation by sensory experience in a mouse model of fragile X syndrome.

    PubMed

    Pan, Feng; Aldridge, Georgina M; Greenough, William T; Gan, Wen-Biao

    2010-10-12

    Fragile X syndrome (FXS) is the most common inherited form of mental retardation and is caused by transcriptional inactivation of the X-linked fragile X mental retardation 1 (FMR1) gene. FXS is associated with increased density and abnormal morphology of dendritic spines, the postsynaptic sites of the majority of excitatory synapses. To better understand how lack of the FMR1 gene function affects spine development and plasticity, we examined spine formation and elimination of layer 5 pyramidal neurons in the whisker barrel cortex of Fmr1 KO mice with a transcranial two-photon imaging technique. We found that the rates of spine formation and elimination over days to weeks were significantly higher in both young and adult KO mice compared with littermate controls. The heightened spine turnover in KO mice was due to the existence of a larger pool of "short-lived" new spines in KO mice than in controls. Furthermore, we found that the formation of new spines and the elimination of existing ones were less sensitive to modulation by sensory experience in KO mice. These results indicate that the loss of Fmr1 gene function leads to ongoing overproduction of transient spines in the primary somatosensory cortex. The insensitivity of spine formation and elimination to sensory alterations in Fmr1 KO mice suggest that the developing synaptic circuits may not be properly tuned by sensory stimuli in FXS.

  15. Radiographic absorptiometry method in measurement of localized alveolar bone density changes.

    PubMed

    Kuhl, E D; Nummikoski, P V

    2000-03-01

    The objective of this study was to measure the accuracy and precision of a radiographic absorptiometry method by using an occlusal density reference wedge in quantification of localized alveolar bone density changes. Twenty-two volunteer subjects had baseline and follow-up radiographs taken of mandibular premolar-molar regions with an occlusal density reference wedge in both films and added bone chips in the baseline films. The absolute bone equivalent densities were calculated in the areas that contained bone chips from the baseline and follow-up radiographs. The differences in densities described the masses of the added bone chips that were then compared with the true masses by using regression analysis. The correlation between the estimated and true bone-chip masses ranged from R = 0.82 to 0.94, depending on the background bone density. There was an average 22% overestimation of the mass of the bone chips when they were in low-density background, and up to 69% overestimation when in high-density background. The precision error of the method, which was calculated from duplicate bone density measurements of non-changing areas in both films, was 4.5%. The accuracy of the intraoral radiographic absorptiometry method is low when used for absolute quantification of bone density. However, the precision of the method is good and the correlation is linear, indicating that the method can be used for serial assessment of bone density changes at individual sites.

  16. Risk factors for water sports-related cervical spine injuries.

    PubMed

    Chang, Spencer K Y; Tominaga, Gail T; Wong, Jan H; Weldon, Edward J; Kaan, Kenneth T

    2006-05-01

    To examine risk factors associated with water sports-related cervical spine injuries (WSCSI). A retrospective analysis of all patients admitted for WSCSI from 1993 to 1997 was performed. The severity of cervical spine injury was assessed by review of medical records and imaging studies. Mechanisms of injury and activities at the time of injury were noted to determine risk factors for cervical spine injuries caused by wave forced impacts (WFI) from activities such as bodysurfing and body boarding. These risks were compared with injuries incurred by shallow water dives (SWD). One hundred patients were analyzed (mean age, 36 years old); 89% were male, 62% were nonresidents of Hawaii, and 75% had a large build. Patients without radiographic evidence of fractures, subluxations, and/or dislocations (n = 26) were significantly older (48 versus 32 years old, p < 0.0001) with a higher rate of pre-existing cervical spine abnormalities (65% versus 15%, p < 0.0001) compared with the remainder of patients (n = 74). Seventy-seven percent of WFI involved nonresidents. The mean age of WFI patients was significantly older than patients involved in SWD (42 versus 25 years). Ninety-six percent of wave-related accidents occurred at moderately to severely rated shorebreak beaches. Wave forced impacts of the head with the ocean bottom typically occurred at moderate to severe shorebreaks, and involved inexperienced, large-build males in their 40s. Spinal stenosis and degenerative spondylosis may increase the risk of cervical spine injury associated with WFI due to the increased risk of neck hyperextension and hyperflexion impacts inherent to this activity.

  17. Gunshot wounds to the spine in adolescents.

    PubMed

    Aryan, Henry E; Amar, Arun P; Ozgur, Burak M; Levy, Michael L

    2005-10-01

    The incidence of spinal instability after penetrating gunshot wounds to the spine in adolescents is unknown. We describe our experience over a 15-year period. Hospital records were reviewed retrospectively. After injury and emergency care, patients were transferred to a rehabilitation facility. Examinations were completed using the American Spinal Injury Association and Frankel scales on admission, discharge, and 6 and 12 months after injury. Severity of injury was described by: 1) degree of neurological damage, 2) degree of preserved neurological function, and 3) presence of instability. Sixty patients were identified with a mean age 15.6 years (+/- 2.7 yr). Twelve patients had cervical, 31 thoracic, and 17 lumbosacral injuries. No operative treatments were used in their care. Thirty-four patients had complete neurological deficits. Mean acute hospitalization was 21.1 days (+/- 22.8 d), and mean rehabilitation stay was 86.3 days (+/- 48.9 d), for a total hospitalization of 107.4 days (+/- 65.9 d). At 1 year, 19 patients were ambulatory and 53 were autonomous. Despite the presence of bony involvement in all, no evidence of spinal instability was noted on follow-up dynamic imaging. Even in two patients with apparent two-column disruption, no instability was noted. At 1-year follow-up, significant (nonfunctional) improvement was noted in the neurological examination (P < 0.0001). Improvements were most notable in those patients with cervical injuries, followed by thoracic and lumbar injuries. After penetrating gunshot wounds to the spine, patients at 1-year follow-up examinations have evidence of significant, but nonfunctional, improvement. No evidence of spinal instability was noted in this study, and no surgical intervention was required.

  18. [Management of spine injuries in polytraumatized patients].

    PubMed

    Heyde, C E; Ertel, W; Kayser, R

    2005-09-01

    The management of spine injuries in polytraumatized patients remains a great challenge for the diagnostic procedures and institution of appropriate treatment by integrating spinal trauma treatment into the whole treatment concept as well as following the treatment steps for the injured spine itself. The established concept of "damage control" and criteria regarding the optimal time and manner for operative treatment of the injured spine in the polytrauma setting is presented and discussed.

  19. Defensive Medicine in U.S. Spine Neurosurgery.

    PubMed

    Din, Ryan S; Yan, Sandra C; Cote, David J; Acosta, Michael A; Smith, Timothy R

    2017-02-01

    Observational cross-sectional survey. To compare defensive practices of U.S. spine and nonspine neurosurgeons in the context of state medical liability risk. Defensive medicine is a commonly reported and costly phenomenon in neurosurgery. Although state liability risk is thought to contribute greatly to defensive practice, variation within neurosurgical specialties has not been well explored. A validated, online survey was sent via email to 3344 members of the American Board of Neurological Surgeons. The instrument contained eight question domains: surgeon characteristics, patient characteristics, practice type, insurance type, surgeon liability profile, basic surgeon reimbursement, surgeon perceptions of medical legal environment, and the practice of defensive medicine. The overall response rate was 30.6% (n = 1026), including 499 neurosurgeons performing mainly spine procedures (48.6%). Spine neurosurgeons had a similar average practice duration as nonspine neurosurgeons (16.6 vs 16.9 years, P = 0.64) and comparable lifetime case volume (4767 vs 4,703, P = 0.71). The average annual malpractice premium for spine neurosurgeons was similar to nonspine neurosurgeons ($104,480.52 vs $101,721.76, P = 0.60). On average, spine neurosurgeons had a significantly higher rate of ordering labs, medications, referrals, procedures, and imaging solely for liability concerns compared with nonspine neurosurgeons (89.2% vs 84.6%, P = 0.031). Multivariate analysis revealed that spine neurosurgeons were roughly 3 times more likely to practice defensively compared with nonspine neurosurgeons (odds ratio, OR = 2.9, P = 0.001) when controlling for high-risk procedures (OR = 7.8, P < 0.001), annual malpractice premium (OR = 3.3, P = 0.01), percentage of patients publicly insured (OR = 1.1, P = 0.80), malpractice claims in the last 3 years (OR = 1.13, P = 0.71), and state medical-legal environment (OR = 1.3, P = 0

  20. The Role of Synaptopodin in Membrane Protein Diffusion in the Dendritic Spine Neck.

    PubMed

    Wang, Lili; Dumoulin, Andréa; Renner, Marianne; Triller, Antoine; Specht, Christian G

    2016-01-01

    The dynamic exchange of neurotransmitter receptors at synapses relies on their lateral diffusion in the plasma membrane. At synapses located on dendritic spines this process is limited by the geometry of the spine neck that restricts the passage of membrane proteins. Biochemical compartmentalisation of the spine is believed to underlie the input-specificity of excitatory synapses and to set the scale on which functional changes can occur. Synaptopodin is located predominantly in the neck of dendritic spines, and is thus ideally placed to regulate the exchange of synaptic membrane proteins. The central aim of our study was to assess whether the presence of synaptopodin influences the mobility of membrane proteins in the spine neck and to characterise whether this was due to direct molecular interactions or to spatial constraints that are related to the structural organisation of the neck. Using single particle tracking we have identified a specific effect of synaptopodin on the diffusion of metabotropic mGluR5 receptors in the spine neck. However, super-resolution STORM/PALM imaging showed that this was not due to direct interactions between the two proteins, but that the presence of synaptopodin is associated with an altered local organisation of the F-actin cytoskeleton, that in turn could restrict the diffusion of membrane proteins with large intracellular domains through the spine neck. This study contributes new data on the way in which the spine neck compartmentalises excitatory synapses. Our data complement models that consider the impact of the spine neck as a function of its shape, by showing that the internal organisation of the neck imposes additional physical barriers to membrane protein diffusion.

  1. The Role of Synaptopodin in Membrane Protein Diffusion in the Dendritic Spine Neck

    PubMed Central

    Wang, Lili; Dumoulin, Andréa; Renner, Marianne; Triller, Antoine; Specht, Christian G.

    2016-01-01

    The dynamic exchange of neurotransmitter receptors at synapses relies on their lateral diffusion in the plasma membrane. At synapses located on dendritic spines this process is limited by the geometry of the spine neck that restricts the passage of membrane proteins. Biochemical compartmentalisation of the spine is believed to underlie the input-specificity of excitatory synapses and to set the scale on which functional changes can occur. Synaptopodin is located predominantly in the neck of dendritic spines, and is thus ideally placed to regulate the exchange of synaptic membrane proteins. The central aim of our study was to assess whether the presence of synaptopodin influences the mobility of membrane proteins in the spine neck and to characterise whether this was due to direct molecular interactions or to spatial constraints that are related to the structural organisation of the neck. Using single particle tracking we have identified a specific effect of synaptopodin on the diffusion of metabotropic mGluR5 receptors in the spine neck. However, super-resolution STORM/PALM imaging showed that this was not due to direct interactions between the two proteins, but that the presence of synaptopodin is associated with an altered local organisation of the F-actin cytoskeleton, that in turn could restrict the diffusion of membrane proteins with large intracellular domains through the spine neck. This study contributes new data on the way in which the spine neck compartmentalises excitatory synapses. Our data complement models that consider the impact of the spine neck as a function of its shape, by showing that the internal organisation of the neck imposes additional physical barriers to membrane protein diffusion. PMID:26840625

  2. The impact of a cervical spine diagnosis on the careers of National Football League athletes.

    PubMed

    Schroeder, Gregory D; Lynch, T Sean; Gibbs, Daniel B; Chow, Ian; LaBelle, Mark W; Patel, Alpesh A; Savage, Jason W; Nuber, Gordon W; Hsu, Wellington K

    2014-05-20

    Cohort study. To determine the effect of cervical spine pathology on athletes entering the National Football League. The association of symptomatic cervical spine pathology with American football athletes has been described; however, it is unknown how preexisting cervical spine pathology affects career performance of a National Football League player. The medical evaluations and imaging reports of American football athletes from 2003 to 2011 during the combine were evaluated. Athletes with a cervical spine diagnosis were matched to controls and career statistics were compiled. Of a total of 2965 evaluated athletes, 143 players met the inclusion criteria. Athletes who attended the National Football League combine without a cervical spine diagnosis were more likely to be drafted than those with a diagnosis (P = 0.001). Players with a cervical spine diagnosis had a decreased total games played (P = 0.01). There was no difference in the number of games started (P = 0.08) or performance score (P = 0.38). In 10 athletes with a sagittal canal diameter of less than 10 mm, there was no difference in years, games played, games started, or performance score (P > 0.24). No neurological injury occurred during their careers. In 7 players who were drafted with a history of cervical spine surgery (4 anterior cervical discectomy and fusion, 2 foraminotomy, and 1 suboccipital craniectomy with a C1 laminectomy), there was no difference in career longevity or performance when compared with matched controls. This study suggests that athletes with preexisting cervical spine pathology were less likely to be drafted than controls. Players with preexisting cervical spine pathology demonstrated a shorter career than those without; however, statistically based performance and numbers of games started were not different. Players with cervical spinal stenosis and those with a history of previous surgery demonstrated no difference in performance-based outcomes and no reports of neurological

  3. Maintenance of dendritic spine morphology by partitioning-defective 1b through regulation of microtubule growth.

    PubMed

    Hayashi, Kenji; Suzuki, Atsushi; Hirai, Syu-ichi; Kurihara, Yasuyuki; Hoogenraad, Casper C; Ohno, Shigeo

    2011-08-24

    Dendritic spines are postsynaptic structures that receive excitatory synaptic input from presynaptic terminals. Actin and its regulatory proteins play a central role in morphogenesis of dendritic spines. In addition, recent studies have revealed that microtubules are indispensable for the maintenance of mature dendritic spine morphology by stochastically invading dendritic spines and regulating dendritic localization of p140Cap, which is required for actin reorganization. However, the regulatory mechanisms of microtubule dynamics remain poorly understood. Partitioning-defective 1b (PAR1b), a cell polarity-regulating serine/threonine protein kinase, is thought to regulate microtubule dynamics by inhibiting microtubule binding of microtubule-associated proteins. Results from the present study demonstrated that PAR1b participates in the maintenance of mature dendritic spine morphology in mouse hippocampal neurons. Immunofluorescent analysis revealed PAR1b localization in the dendrites, which was concentrated in dendritic spines of mature neurons. PAR1b knock-down cells exhibited decreased mushroom-like dendritic spines, as well as increased filopodia-like dendritic protrusions, with no effect on the number of protrusions. Live imaging of microtubule plus-end tracking proteins directly revealed decreases in distance and duration of microtubule growth following PAR1b knockdown in a neuroblastoma cell line and in dendrites of hippocampal neurons. In addition, reduced accumulation of GFP-p140Cap in dendritic protrusions was confirmed in PAR1b knock-down neurons. In conclusion, the present results suggested a novel function for PAR1b in the maintenance of mature dendritic spine morphology by regulating microtubule growth and the accumulation of p140Cap in dendritic spines.

  4. Accuracy and precision of computer-assisted analysis of bone density via conventional and digital radiography in relation to dual-energy x-ray absorptiometry.

    PubMed

    Vaccaro, Calogero; Busetto, Roberto; Bernardini, Daniele; Anselmi, Carlo; Zotti, Alessandro

    2012-03-01

    To evaluate the precision and accuracy of assessing bone mineral density (BMD) by use of mean gray value (MGV) on digitalized and digital images of conventional and digital radiographs, respectively, of ex vivo bovine and equine bone specimens in relation to the gold-standard technique of dual-energy x-ray absorptiometry (DEXA). Left and right metatarsal bones from 11 beef cattle and right femurs from 2 horses. Bovine specimens were imaged by use of conventional radiography, whereas equine specimens were imaged by use of computed radiography (digital radiography). Each specimen was subsequently scanned by use of the same DEXA equipment. The BMD values resulting from each DEXA scan were paired with the MGVs obtained by use of software on the corresponding digitalized or digital radiographic image. The MGV analysis of digitalized and digital x-ray images was a precise (coefficient of variation, 0.1 and 0.09, respectively) and highly accurate method for assessing BMD, compared with DEXA (correlation coefficient, 0.910 and 0.937 for conventional and digital radiography, respectively). The high correlation between MGV and BMD indicated that MGV analysis may be a reliable alternative to DEXA in assessing radiographic bone density. This may provide a new, inexpensive, and readily available estimate of BMD.

  5. ²⁶Mg labeling of the sea urchin regenerating spine: Insights into echinoderm biomineralization process.

    PubMed

    Gorzelak, Przemysław; Stolarski, Jarosław; Dubois, Philippe; Kopp, Christophe; Meibom, Anders

    2011-10-01

    This paper reports the results of the first dynamic labeling experiment with regenerating spines of sea urchins Paracentrotus lividus using the stable isotope ²⁶Mg and NanoSIMS high-resolution isotopic imaging, which provide a direct information about the growth process. Growing spines were labeled twice (for 72 and 24 h, respectively) by increasing the abundance of ²⁶Mg in seawater. The incorporation of ²⁶Mg into the growing spines was subsequently imaged with the NanoSIMS ion microprobe. Stereom trabeculae initially grow as conical micro-spines, which form within less than 1 day. These micro-spines fuse together by lateral outgrowths and form a thin, open meshwork (inner stereom), which is subsequently reinforced by addition of layered thickening deposits (outer stereom). The (longitudinal) growth rate of the inner stereom is ca. 125 μm/day. A single (ca. 1 μm) thickening layer in the stereom trabeculae is deposited during 24h. The thickening process is contemporaneous with the formation micro-spines and involves both longitudinal trabeculae and transverse bridges to a similar degree. Furthermore, the skeleton-forming cells remain active in the previously formed open stereom for at least 10 days, and do not migrate upwards until the end of the thickening process. The experimental capability presented here provides a new way to obtain detailed information about the skeleton formation of a multitude of marine, calcite producing organisms. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. Biphasic synovial sarcoma in the cervical spine: Case report.

    PubMed

    Foreman, Stephen M; Stahl, Michael J

    2011-05-23

    Synovial sarcoma is a rare malignant neoplasm of soft tissue that typically arising near large joints of the upper and lower extremities in young adult males. Only 3% of these neoplasms have been found to arise in the head and neck region. To our knowledge, there are limited reports in the literature of this neoplasm in the cervical spine.A case of biphasic synovial sarcoma of the cervical spine is reviewed. A 29 year-old male presented with pain on the left side of the cervical spine. Physical examination revealed a global loss of cervical motion and large, palpable mass in the left paravertebral area. The long-delayed Magnetic Resonance (MR) scan revealed a soft tissue mass measuring 8.3 centimeters (cm) × 5.7 cm that was surgically removed. A malignant biphasic synovial sarcoma was diagnosed on pathologic examination.The clinical and imaging findings of an atypically located synovial sarcoma are reviewed. This case report emphasizes the consequences of a limited differential diagnosis, prolonged treatment and the failure to perform timely diagnostic imaging in the presence of a paraspinal mass.

  7. A 7T spine array based on electric dipole transmitters.

    PubMed

    Duan, Qi; Nair, Govind; Gudino, Natalia; de Zwart, Jacco A; van Gelderen, Peter; Murphy-Boesch, Joe; Reich, Daniel S; Duyn, Jeff H; Merkle, Hellmut

    2015-10-01

    The goal of this study was to explore the feasibility of using an array of electric dipole antennas for RF transmission in spine MRI at high fields. A two-channel transmit array based on an electric dipole design was quantitatively optimized for 7T spine imaging and integrated with a receive array combining eight loop coils. Using B1+ mapping, the transmit efficiency of the dipole array was compared with a design using quadrature loop pairs. The radiofrequency energy deposition for each array was measured using a home-built dielectric phantom and MR thermometry. The performance of the proposed array was qualitatively demonstrated in human studies. The results indicate dramatically improved transmit efficiency for the dipole design compared with the loop excitation. A gain of up to 76% was achieved within the spinal region. For imaging of the spine, electric dipole-based transmitters provide an attractive alternative to the traditional loop-based design. Easy integration with existing receive array technology facilitates practical use at high fields. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  8. A 7T Spine Array Based on Electric Dipole Transmitters

    PubMed Central

    Duan, Qi; Nair, Govind; Gudino, Natalia; de Zwart, Jacco A.; van Gelderen, Peter; Murphy-Boesch, Joe; Reich, Daniel S.; Duyn, Jeff H.; Merkle, Hellmut

    2015-01-01

    Purpose In this work the feasibility of using an array of electric dipole antennas for RF transmission in spine MRI at high field is explored. Method A 2-channel transmit array based on an electric dipole design was quantitatively optimized for 7T spine imaging and integrated with a receive array combining 8 loop coils. Using B1+ mapping, the transmit efficiency of the dipole array was compared to a design using quadrature loop pairs. The radio-frequency (RF) energy deposition for each array was measured using a home-built dielectric phantom and MR thermometry. The performance of the proposed array was qualitatively demonstrated in human studies. Results The results indicate dramatically improved transmit efficiency for the dipole design as compared to the loop excitation. Up to 76% gain was achieved within the spinal region. Conclusion For imaging of the spine, electric-dipole based transmitters provided an attractive alternative to the traditional loop-based design. Easy integration with existing receive array technology facilitates practical use at high field. PMID:26190585

  9. Cortical thickness estimation of the proximal femur from multi-view dual-energy X-ray absorptiometry (DXA)

    NASA Astrophysics Data System (ADS)

    Tsaousis, N.; Gee, A. H.; Treece, G. M.; Poole, K. E. S.

    2013-02-01

    Hip fracture is the leading cause of acute orthopaedic hospital admission amongst the elderly, with around a third of patients not surviving one year post-fracture. Although various preventative therapies are available, patient selection is difficult. The current state-of-the-art risk assessment tool (FRAX) ignores focal structural defects, such as cortical bone thinning, a critical component in characterizing hip fragility. Cortical thickness can be measured using CT, but this is expensive and involves a significant radiation dose. Instead, Dual-Energy X-ray Absorptiometry (DXA) is currently the preferred imaging modality for assessing hip fracture risk and is used routinely in clinical practice. Our ambition is to develop a tool to measure cortical thickness using multi-view DXA instead of CT. In this initial study, we work with digitally reconstructed radiographs (DRRs) derived from CT data as a surrogate for DXA scans: this enables us to compare directly the thickness estimates with the gold standard CT results. Our approach involves a model-based femoral shape reconstruction followed by a data-driven algorithm to extract numerous cortical thickness point estimates. In a series of experiments on the shaft and trochanteric regions of 48 proximal femurs, we validated our algorithm and established its performance limits using 20 views in the range 0°-171°: estimation errors were 0:19 +/- 0:53mm (mean +/- one standard deviation). In a more clinically viable protocol using four views in the range 0°-51°, where no other bony structures obstruct the projection of the femur, measurement errors were -0:07 +/- 0:79 mm.

  10. Application of the World Health Organization Fracture Risk Assessment Tool to predict need for dual-energy X-ray absorptiometry scanning in postmenopausal women.

    PubMed

    Chao, An-Shine; Chen, Fang-Ping; Lin, Yu-Ching; Huang, Ting-Shuo; Fan, Chih-Ming; Yu, Yu-Wei

    2015-12-01

    To evaluate the efficacy of the World Health Organization Fracture Risk Assessment Tool, excluding bone mineral density (pre-BMD FRAX), in identifying Taiwanese postmenopausal women needing dual-energy X-ray absorptiometry (DXA) examination for further treatment. The pre-BMD FRAX score was calculated for 231 postmenopausal women who participated in public health education workshops in the local Keelung community, Taiwan. DXA scanning and vertebral fracture assessment (VFA) were arranged for women classified as intermediate or high risk for fracture using the pre-BMD FRAX fracture probability. Pre-BMD FRAX classified 26 women as intermediate risk and 37 as having high risk for fracture. Subsequent DXA scans for these 63 women showed that 36 were osteoporotic, 19 were osteopenic, and eight had normal bone density. Concurrent VFA revealed 25 spine factures in which 14 were osteoporotic, seven were osteopenic, and four had normal bone density. The efficacy of the pre-BMD FRAX score to identify those patients with low bone mass by DXA was 87.3% (55/63). When VFA was combined with BMD to identify those patients with high risk (osteopenia, osteoporosis, or spinal fracture), the efficacy of the pre-BMD score increased to 93.7% (59/63). According to the National Osteoporosis Foundation, the overall concordance between pre-BMD FRAX and BMD, expressed through the kappa index, was 0.967. Compared with the evaluation when BMD was used alone, there was a significant increase in efficacy in identifying women who need treatment using BMD plus VFA or FRAX plus BMD. Furthermore, the highest efficacy was achieved when FRAX with BMD and VFA was used. The pre-BMD FRAX score not only efficiently predicts postmenopausal patients who are potentially at risk and might require treatment but also reduces unnecessary DXA use. Concurrent VFA during DXA use increases spine fracture detection. This improvement in diagnostic efficacy allows clinicians to provide the most appropriate therapeutic

  11. Mass flows in a prominence spine as observed in EUV

    SciTech Connect

    Kucera, T. A.; Gilbert, H. R.; Karpen, J. T.

    2014-07-20

    We analyze a quiescent prominence observed by the Solar Dynamics Observatory's Atmospheric Imaging Assembly (AIA) with a focus on mass and energy flux in the spine, measured using Lyman continuum absorption. This is the first time this type of analysis has been applied with an emphasis on individual features and fluxes in a quiescent prominence. The prominence, observed on 2010 September 28, is detectable in most AIA wavebands in absorption and/or emission. Flows along the spine exhibit horizontal bands 5''-10'' wide and kinetic energy fluxes on the order of a few times 10{sup 5} erg s{sup –1}cm{sup –2}, consistent withmore » quiet sun coronal heating estimates. For a discrete moving feature we estimate a mass of a few times 10{sup 11} g. We discuss the implications of our derived properties for a model of prominence dynamics, the thermal non-equilibrium model.« less

  12. The dendritic spine story: an intriguing process of discovery

    PubMed Central

    DeFelipe, Javier

    2015-01-01

    Dendritic spines are key components of a variety of microcircuits and they represent the majority of postsynaptic targets of glutamatergic axon terminals in the brain. The present article will focus on the discovery of dendritic spines, which was possible thanks to the application of the Golgi technique to the study of the nervous system, and will also explore the early interpretation of these elements. This discovery represents an interesting chapter in the history of neuroscience as it shows us that progress in the study of the structure of the nervous system is based not only on the emergence of new techniques but also on our ability to exploit the methods already available and correctly interpret their microscopic images. PMID:25798090

  13. The dendritic spine story: an intriguing process of discovery.

    PubMed

    DeFelipe, Javier

    2015-01-01

    Dendritic spines are key components of a variety of microcircuits and they represent the majority of postsynaptic targets of glutamatergic axon terminals in the brain. The present article will focus on the discovery of dendritic spines, which was possible thanks to the application of the Golgi technique to the study of the nervous system, and will also explore the early interpretation of these elements. This discovery represents an interesting chapter in the history of neuroscience as it shows us that progress in the study of the structure of the nervous system is based not only on the emergence of new techniques but also on our ability to exploit the methods already available and correctly interpret their microscopic images.

  14. Reliability of analysis of the bone mineral density of the second and fifth metatarsals using dual-energy x-ray absorptiometry (DXA).

    PubMed

    Pritchard, N Stewart; Smoliga, James M; Nguyen, Anh-Dung; Branscomb, Micah C; Sinacore, David R; Taylor, Jeffrey B; Ford, Kevin R

    2017-01-01

    Metatarsal fractures, especially of the fifth metatarsal, are common injuries of the foot in a young athletic population, but the risk factors for this injury are not well understood. Dual-energy x-ray absorptiometry (DXA) provides reliable measures of regional bone mineral density to predict fracture risk in the hip and lumbar spine. Recently, sub-regional metatarsal reliability was established in fresh cadaveric specimens and associated with ultimate fracture force. The purpose of this study was to assess the reliability of DXA bone mineral density measurements of sub-regions of the second and fifth metatarsals in a young, active population. Thirty two recreationally active individuals participated in the study, and the bone density of the second (2MT) and fifth (5MT) metatarsals of each subject was measured using a Hologic QDR x-ray bone densitometer. Scans were analyzed separately by two raters, and regional bone mineral density, bone mineral content, and area measurements were calculated for the proximal, shaft, and distal regions of the bone. Intra-rater, inter-rater, and scan-rescan reliability were then determined for each region. Proximal and shaft bone mineral density measurements of the second and fifth metatarsal were reliable. ICC's were variable across regions and metatarsals, with the distal region being the poorest. Bone mineral density measurements of the metatarsals may be a better indicator of fracture risk of the metatarsals than whole body measurements. A reliable method for measuring the regional bone mineral densities of the metatarsals was found. However, inter-rater reliability and scan-rescan reliability for the distal regions were poor. Future research should examine the relationship between DXA bone mineral density measurements and fracture risk at the metatarsals.

  15. Comparison of DXA Scans and Conventional X-rays for Spine Morphometry and Bone Age Determination in Children.

    PubMed

    Hoyer-Kuhn, Heike; Knoop, Kai; Semler, Oliver; Kuhr, Kathrin; Hellmich, Martin; Schoenau, Eckhard; Koerber, Friederike

    2016-01-01

    Conventional lateral spine and hand radiographs are the standard tools to evaluate vertebral morphometry and bone age in children. Beside bone mineral density analyses, dual-energy X-ray absorptiometry (DXA) measurements with lower radiation exposure provide high-resolution scans which are not approved for diagnostic purposes. Data about the comparability of conventional radiographs and DXA in children are missing yet. The purpose of the trial was to evaluate whether conventional hand and spine radiographs can be replaced by DXA scans to diminish radiation exposure. Thirty-eight children with osteogenesis imperfecta or secondary osteoporosis or short stature (male, n=20; age, 5.0-17.0 yr) were included and assessed once by additional DXA (GE iDXA) of the spine or the left hand. Intraclass correlation coefficients (ICCs) were used to express agreement between X-ray and iDXA assessment. Evaluation of the spine morphometry showed reasonable agreement between iDXA and radiography (ICC for fish-shape, 0.75; for wedge-shape, 0.65; and for compression fractures, 0.70). Bone age determination showed excellent agreement between iDXA and radiography (ICC, 0.97). IDXA-scans of the spine in a pediatric population should be used not only to assess bone mineral density but also to evaluate anatomic structures and vertebral morphometry. Therefore, iDXA can replace some radiographs in children with skeletal diseases. Copyright © 2016 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

  16. Cadaveric verification of the Eclipse AAA algorithm for spine SBRT treatments with titanium hardware.

    PubMed

    Grams, Michael P; Fong de Los Santos, Luis E; Antolak, John A; Brinkmann, Debra H; Clarke, Michelle J; Park, Sean S; Olivier, Kenneth R; Whitaker, Thomas J

    2016-01-01

    To assess the accuracy of the Eclipse Analytical Anisotropic Algorithm when calculating dose for spine stereotactic body radiation therapy treatments involving surgically implanted titanium hardware. A human spine was removed from a cadaver, cut sagittally along the midline, and then separated into thoracic and lumbar sections. The thoracic section was implanted with titanium stabilization hardware; the lumbar section was not implanted. Spine sections were secured in a water phantom and simulated for treatment planning using both standard and extended computed tomography (CT) scales. Target volumes were created on both spine sections. Dose calculations were performed using (1) the standard CT scale with relative electron density (RED) override of image artifacts and hardware, (2) the extended CT scale with RED override of image artifacts only, and (3) the standard CT scale with no RED overrides for hardware or artifacts. Plans were delivered with volumetric modulated arc therapy using a 6-MV beam with and without a flattening filter. A total of 3 measurements for each plan were made with Gafchromic film placed between the spine sections and compared with Eclipse dose calculations using gamma analysis with a 2%/2 mm passing criteria. A single measurement in a homogeneous phantom was made for each plan before actual delivery. Gamma passing rates for measurements in the homogeneous phantom were 99.6% or greater. Passing rates for measurements made in the lumbar spine section without hardware were 99.3% or greater; measurements made in the thoracic spine containing titanium were 98.6 to 99.5%. Eclipse Analytical Anisotropic Algorithm can adequately model the effects of titanium implants for spine stereotactic body radiation therapy treatments using volumetric modulated arc therapy. Calculations with standard or extended CT scales give similarly accurate results. Copyright © 2016 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

  17. A DXA Whole Body Composition Cross-Calibration Experience: Evaluation With Humans, Spine, and Whole Body Phantoms.

    PubMed

    Krueger, Diane; Libber, Jessie; Sanfilippo, Jennifer; Yu, Hui Jing; Horvath, Blaine; Miller, Colin G; Binkley, Neil

    2016-01-01

    New densitometer installation requires cross-calibration for accurate longitudinal assessment. When replacing a unit with the same model, the International Society for Clinical Densitometry recommends cross-calibrating by scanning phantoms 10 times on each instrument and states that spine bone mineral density (BMD) should be within 1%, whereas total body lean, fat, and %fat mass should be within 2% of the prior instrument. However, there is limited validation that these recommendations provide adequate total body cross-calibration. Here, we report a total body cross-calibration experience with phantoms and humans. Cross-calibration between an existing and new Lunar iDXA was performed using 3 encapsulated spine phantoms (GE [GE Lunar, Madison, WI], BioClinica [BioClinica Inc, Princeton, NJ], and Hologic [Hologic Inc, Bedford, MA]), 1 total body composition phantom (BioClinica), and 30 human volunteers. Thirty scans of each phantom and a total body scan of human volunteers were obtained on each instrument. All spine phantom BMD means were similar (within 1%; <-0.010 g/cm2 bias) between the existing and new dual-energy X-ray absorptiometry unit. The BioClinica body composition phantom (BBCP) BMD and bone mineral content (BMC) values were within 2% with biases of 0.005 g/cm2 and -3.4 g. However, lean and fat mass and %fat differed by 4.6%-7.7% with biases of +463 g, -496 g, and -2.8%, respectively. In vivo comparison supported BBCP data; BMD and BMC were within ∼2%, but lean and fat mass and %fat differed from 1.6% to 4.9% with biases of +833 g, -860 g, and -1.1%. As all body composition comparisons exceeded the recommended 2%, the new densitometer was recalibrated. After recalibration, in vivo bias was lower (<0.05%) for lean and fat; -23 and -5 g, respectively. Similarly, BBCP lean and fat agreement improved. In conclusion, the BBCP behaves similarly, but not identical, to human in vivo measurements for densitometer cross-calibration. Spine phantoms, despite good

  18. Quantitative ultrasound and dual-energy X-ray absorptiometry in the prediction of fragility fracture in men.

    PubMed

    Gonnelli, Stefano; Cepollaro, Chiara; Gennari, Luigi; Montagnani, Andrea; Caffarelli, Carla; Merlotti, Daniela; Rossi, Stefania; Cadirni, Alice; Nuti, Ranuccio

    2005-08-01

    Fragility fractures in men represent a major health problem, and this prompts a necessity for reliable tools for the identification of men at risk of fracture. In order to assess the ability of dual-energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) in the prediction of fracture risk in men and whether their combination might be useful in a clinical setting, we studied 401 men (age range 45-82 years, mean 60.3+/-12.5), of whom 133 had osteoporotic fractures and 268 did not. In all subjects we measured bone mineral density at the lumbar spine (BMD-LS) and at the femur, calculating thereafter the standard femoral subregions: neck (BMD-FN), total hip (BMD-T), trochanter (BMD-TR), intertrochanter (BMD-ITR), and Ward's triangle (BMD-W), by DXA. We also performed ultrasound parameters at the calcaneus: speed of sound (SOS), broadband ultrasound attenuation (BUA) and Stiffness, by Achilles plus, and at the phalanxes: amplitude dependent speed of sound (AD-SoS) and the parameters of the graphic trace: bone transmission time (BTT), fast wave amplitude (FWA), signal dynamic (SDy) and ultrasound bone profile index (UBPI), by Bone Profiler. All DXA and QUS parameters, apart from FWA, were significantly (P<0.001) lower in patients with a history of fracture. BMD at the proximal femur showed the best ability in discriminating men with or without fractures. QUS at the heel showed discriminatory ability significantly better than QUS at the fingers. By logistic regression analysis, adjusted for age and BMI, BMD-T showed the best association with fragility fracture [odds ratio (OR)=3.43, 95% confidence interval (CI)=2.47-4.77]. Among QUS parameters, the highest value of the OR was shown by stiffness (OR=3.18, CI=2.27-4.48). FWA and SDy were not associated with fragility fractures in men. If DXA and QUS were combined, the prediction of the OR of fragility fracture events in men increases; in fact Stiffness was able to increase the OR when added to BMD-LS (OR=5.44, CI

  19. Posterior Bilateral Intermuscular Approach for Upper Cervical Spine Injuries.

    PubMed

    Xu, Yong; Xiong, Wei; Han, Sung I I; Fang, Zhong; Li, Feng

    2017-08-01

    To investigate a novel intermuscular surgical approach for posterior upper cervical spine fixation. Twenty-three healthy volunteers underwent magnetic resonance imaging. By using the magnetic resonance imaging scans in transverse view at the level of lower edge of atlas, the distances from the posterior midline to lateral margin of trapezius, to the medial margin of splenius capitis, and to middle line of semispinalis capitis were recorded. The angle between posterior middle line and the line crossing the lateral margin of trapezius and middle point of ipsilateral pedicles. From October 2009 to May 2013, 12 patients with upper cervical spine injuries were operated via the bilateral intermuscular approach. The time required for surgery, blood loss, and pre- and postoperative visual analogue scale scores were analyzed. The average distance of 0-T was 39.2 ± 7.5 mm, the angle between the approach and posterior middle line was 33.2 ± 8.4°. The surgical time was 78.3 ± 22.5 minutes (45-140 minutes), and the mean intraoperative blood loss was 87.5 ± 44.2 mL (30-200 mL). Preoperative and postoperative visual analogue scale scores were 6.4 ± 0.8 and 1.8 ± 0.7, respectively. The average follow-up time was 19.7 ± 11.5 months (9-48 months). The posterior bilateral intermuscular approach for upper cervical spine injuries is a valid alternative for Hangmans' fractures type I, type II, and type Ia according to Levine and Edwards classification as well as atlantoaxial subluxation caused by upper cervical spine trauma. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Clinical utility for diffusion MRI sequence in emergency and inpatient spine protocols.

    PubMed

    Hoch, Michael J; Rispoli, Joanne; Bruno, Mary; Wauchope, Mervin; Lui, Yvonne W; Shepherd, Timothy M

    Diffusion imaging of the spine has the potential to change clinical management, but is challenging due to the small size of the cord and susceptibility artifacts from adjacent structures. Reduced field-of-view (rFOV) diffusion can improve image quality by decreasing the echo train length. Over the past 2 years, we have acquired a rFOV diffusion sequence for MRI spine protocols on most inpatients and emergency room patients. We provide selected imaging diagnoses to illustrate the utility of including diffusion spine MRI in clinical practice. Our experiences support using diffusion MRI to improve diagnostic certainty and facilitate prompt treatment or clinical management. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Fungal infections of the spine.

    PubMed

    Kim, Choll W; Perry, Andrew; Currier, Brad; Yaszemski, Michael; Garfin, Steven R

    2006-03-01

    Fungal infections of the spine are relatively uncommon. Fungi such as Coccidioides immitis and Blastomyces dermatitidis are limited to specific geographical areas whereas cryptococcus, candida, and aspergillus are found worldwide. Candida and aspergillus are normal commensals of the body and produce disease in susceptible organisms when they gain access to the vascular system through intravenous lines, during implantation of prosthetic devices, or during surgery. For the other fungi, spinal involvement usually is the result of hematogenous or direct spread of organisms from an initial pulmonary source of infection. Involvement of the vertebral bodies can lead to vertebral compression fractures and gross deformity of the spine. Spread of infection along the anterior longitudinal ligament can lead to psoas or paravertebral abscesses. Early recognition of the disease requires a high index of suspicion, proper travel history, and a detailed physical examination. Treatment relies on the prompt institution of appropriate pharmacotherapy and constant monitoring of clinical progress. Resistance to medical therapy, spinal instability, and neurologic deficits are indications for débridement and stabilization with spinal fusion. Prognosis depends on the premorbid state of the patient, the type of fungal organism, and the timing of treatment. Level V (expert opinion). Please see the Guidelines for Authors for a complete description of levels of evidence.

  2. Siamese convolutional networks for tracking the spine motion

    NASA Astrophysics Data System (ADS)

    Liu, Yuan; Sui, Xiubao; Sun, Yicheng; Liu, Chengwei; Hu, Yong

    2017-09-01

    Deep learning models have demonstrated great success in various computer vision tasks such as image classification and object tracking. However, tracking the lumbar spine by digitalized video fluoroscopic imaging (DVFI), which can quantitatively analyze the motion mode of spine to diagnose lumbar instability, has not yet been well developed due to the lack of steady and robust tracking method. In this paper, we propose a novel visual tracking algorithm of the lumbar vertebra motion based on a Siamese convolutional neural network (CNN) model. We train a full-convolutional neural network offline to learn generic image features. The network is trained to learn a similarity function that compares the labeled target in the first frame with the candidate patches in the current frame. The similarity function returns a high score if the two images depict the same object. Once learned, the similarity function is used to track a previously unseen object without any adapting online. In the current frame, our tracker is performed by evaluating the candidate rotated patches sampled around the previous frame target position and presents a rotated bounding box to locate the predicted target precisely. Results indicate that the proposed tracking method can detect the lumbar vertebra steadily and robustly. Especially for images with low contrast and cluttered background, the presented tracker can still achieve good tracking performance. Further, the proposed algorithm operates at high speed for real time tracking.

  3. Utility of three-dimensional and multiplanar reformatted computed tomography for evaluation of pediatric congenital spine abnormalities.

    PubMed

    Newton, Peter O; Hahn, Gregory W; Fricka, Kevin B; Wenger, Dennis R

    2002-04-15

    A retrospective radiographic review of 31 patients with congenital spine abnormalities who underwent conventional radiography and advanced imaging studies was conducted. To analyze the utility of three-dimensional computed tomography with multiplanar reformatted images for congenital spine anomalies, as compared with plain radiographs and axial two-dimensional computed tomography imaging. Conventional radiographic imaging for congenital spine disorders often are difficult to interpret because of the patient's small size, the complexity of the disorder, a deformity not in the plane of the radiographs, superimposed structures, and difficulty in forming a mental three-dimensional image. Multiplanar reformatted and three-dimensional computed tomographic imaging offers many potential advantages for defining congenital spine anomalies including visualization of the deformity in any plane, from any angle, with the overlying structures subtracted. The imaging studies of patients who had undergone a three-dimensional computed tomography for congenital deformities of the spine between 1992 and 1998 were reviewed (31 cases). All plain radiographs and axial two-dimensional computed tomography images performed before the three-dimensional computed tomography were reviewed and the findings documented. This was repeated for the three-dimensional reconstructions and, when available, the multiplanar reformatted images (15 cases). In each case, the utility of the advanced imaging was graded as one of the following: Grade A (substantial new information obtained), Grade B (confirmatory with improved visualization and understanding of the deformity), and Grade C (no added useful information obtained). In 17 of 31 cases, the multiplanar reformatted and three-dimensional images allowed identification of unrecognized malformations. In nine additional cases, the advanced imaging was helpful in better visualizing and understanding previously identified deformities. In five cases, no new

  4. Cellular Therapy to Obtain Spine Fusion

    DTIC Science & Technology

    2012-07-01

    competent and incompetent models the radio-micrographs show a distinct scoliosis in 6 month old growing mice, which received the Ad5BMP2 transduced cells...cells. Panel C, shows obvious curvature of the spine suggesting a significant scoliosis , as compared to the normal mouse spine, shown in panel B

  5. Ratfish (Chimaera) spine injuries in fishermen.

    PubMed

    Hayes, A J; Sim, A J W

    2011-08-01

    An occupational hazard peculiar to fishermen, is an injury from a sharp fish spine. Such spines can cause envenomation injury, infectious sequelae or trauma to anatomical structures. The management of two fishermen with penetrating ratfish (Chimaera) spine injuries to the lower limb is described. Both were managed by removal of the spine under general anaesthesia. In the second patient, the spine was embedded adjacent to the left femoral artery, highlighting the potential for major haemorrhage and supporting the use of surgical wound exploration when important structures may be involved. Herein, we describe the first report in English of Chimaera spine injury. In addition, we surveyed nine northeast Atlantic deep-sea fishermen to gain information on exposure to, and injuries from, this type of fish. The most commonly identified species was Chimaera monstrosa. Five fishermen reported injuries to their feet or hands from Chimaera spines and two had sought medical attention. The evidence indicates that deep-sea trawler fishermen of the northeast Atlantic frequently encounter Chimaera species and can suffer dangerous penetrating wounds from its dorsal spine.

  6. The short-time structural plasticity of dendritic spines is altered in a model of Rett syndrome.

    PubMed

    Landi, Silvia; Putignano, Elena; Boggio, Elena Maria; Giustetto, Maurizio; Pizzorusso, Tommaso; Ratto, Gian Michele

    2011-01-01

    The maturation of excitatory transmission comes about through a developmental period in which dendritic spines are highly motile and their number, form and size are rapidly changing. Surprisingly, although these processes are crucial for the formation of cortical circuitry, little is known about possible alterations of these processes in brain disease. By means of acute in vivo 2-photon imaging we show that the dynamic properties of dendritic spines of layer V cortical neurons are deeply affected in a mouse model of Rett syndrome (RTT) at a time around P25 when the neuronal phenotype of the disease is still mild. Then, we show that 24h after a subcutaneous injection of IGF-1 spine dynamics is restored. Our study demonstrates that spine dynamics in RTT mice is severely impaired early during development and suggest that treatments for RTT should be started very early in order to reestablish a normal period of spine plasticity.

  7. Study of bone mineral density in lumbar spine and femoral neck in a Spanish population. Multicentre Research Project on Osteoporosis.

    PubMed

    Diaz Curiel, M; Carrasco de la Peña, J L; Honorato Perez, J; Perez Cano, R; Rapado, A; Ruiz Martinez, I

    1997-01-01

    The aim of this study was to generate standard curves for bone mineral density (BMD) in a Spanish population using dual-energy X-ray absorptiometry (DXA), at both lumbar spine and femoral neck sites. The total sample size was 2442 subjects of both sexes aged 20-80 years, stratified according to survival rates, demographic distribution by local regions and sex ratio in the Spanish population. Subjects with suspected conditions affecting bone metabolism or receiving any treatment affecting bone mineralization were excluded. The study was carried out in 14 hospitals and bone density measurements were performed, using a QDR/ 1000 Hologic device. In the female population, the highest value for lumbar spine BMD was found within the 30-39 years age group, being significantly lower after the age of 49 years. In the male population, the highest values for lumbar spine BMD are found one decade earlier than in the female population and become significantly lower after the age of 69 years. The highest values for femoral neck BMD in men and women was found in the 20-29 year age group. Values for femoral neck BMD in the female population become statistically lower after the age of 49 years, while in the male population this effect was seen after the age of 69 years. Values for femoral neck BMD were higher in men than women at all ages.

  8. Dendritic spine dysgenesis in Autism Related Disorders

    PubMed Central

    Phillips, Mary; Pozzo-Miller, Lucas

    2015-01-01

    The activity-dependent structural and functional plasticity of dendritic spines has led to the long-standing belief that these neuronal compartments are the subcellular sites of learning and memory. Of relevance to human health, central neurons in several neuropsychiatric illnesses, including autism related disorders, have atypical numbers and morphologies of dendritic spines. These so-called dendritic spine dysgeneses found in individuals with autism related disorders are consistently replicated in experimental mouse models. Dendritic spine dysgenesis reflects the underlying synaptopathology that drives clinically relevant behavioral deficits in experimental mouse models, providing a platform for testing new therapeutic approaches. By examining molecular signaling pathways, synaptic deficits, and spine dysgenesis in experimental mouse models of autism related disorders we find strong evidence for mTOR to be a critical point of convergence and promising therapeutic target. PMID:25578949

  9. Dendritic spine dysgenesis in autism related disorders.

    PubMed

    Phillips, Mary; Pozzo-Miller, Lucas

    2015-08-05

    The activity-dependent structural and functional plasticity of dendritic spines has led to the long-standing belief that these neuronal compartments are the subcellular sites of learning and memory. Of relevance to human health, central neurons in several neuropsychiatric illnesses, including autism related disorders, have atypical numbers and morphologies of dendritic spines. These so-called dendritic spine dysgeneses found in individuals with autism related disorders are consistently replicated in experimental mouse models. Dendritic spine dysgenesis reflects the underlying synaptopathology that drives clinically relevant behavioral deficits in experimental mouse models, providing a platform for testing new therapeutic approaches. By examining molecular signaling pathways, synaptic deficits, and spine dysgenesis in experimental mouse models of autism related disorders we find strong evidence for mTOR to be a critical point of convergence and promising therapeutic target. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. Radiation exposure in X-ray-based imaging techniques used in osteoporosis

    PubMed Central

    Adams, Judith E.; Guglielmi, Giuseppe; Link, Thomas M.

    2010-01-01

    Recent advances in medical X-ray imaging have enabled the development of new techniques capable of assessing not only bone quantity but also structure. This article provides (a) a brief review of the current X-ray methods used for quantitative assessment of the skeleton, (b) data on the levels of radiation exposure associated with these methods and (c) information about radiation safety issues. Radiation doses associated with dual-energy X-ray absorptiometry are very low. However, as with any X-ray imaging technique, each particular examination must always be clinically justified. When an examination is justified, the emphasis must be on dose optimisation of imaging protocols. Dose optimisation is more important for paediatric examinations because children are more vulnerable to radiation than adults. Methods based on multi-detector CT (MDCT) are associated with higher radiation doses. New 3D volumetric hip and spine quantitative computed tomography (QCT) techniques and high-resolution MDCT for evaluation of bone structure deliver doses to patients from 1 to 3 mSv. Low-dose protocols are needed to reduce radiation exposure from these methods and minimise associated health risks. PMID:20559834

  11. The importance of preoperative tissue sampling for mobile spine chordomas: literature review and report of two cases.

    PubMed

    Zuccato, Jeffrey A; Witiw, Christopher D; Keith, Julia; Dyer, Erin; Saghal, Arjun; da Costa, Leodante

    2018-01-01

    Pre-operative biopsy and diagnosis of chordomas of the mobile spine is indicated as en bloc resections improve outcomes. This review of the management of mobile spine chordomas includes two cases of unexpected mobile spine chordomas where a preoperative tissue diagnosis was decided against and may have altered surgical decision-making. Two lumbar spine chordomas thought to be metastatic and primary bony lesions preoperatively were not biopsied before surgery and eventual pathology revealed chordoma. Preoperative diagnoses were questioned during surgery after an intraoperative tissue diagnosis of chordoma in one case and unclear pathology with non-characteristic tumor morphology in the other. The surgical plan was altered in these cases to maximize resection as en bloc resection reduces the risk of local recurrence in chordoma. Mobile spine chordomas are rare and en bloc resection is recommended, contrary to the usual approach to more common spine tumors. Since en bloc resection of spine chordomas improves disease free survival, it has been recommended that tissue diagnosis be obtained preoperatively when chordoma is considered in the differential diagnosis, in order to guide surgical planning. We present two cases where a preoperative biopsy was considered but not obtained after neuroradiology consultation and imaging review, which may have been managed differently if the diagnosis of spine chordomas were known pre-operatively.

  12. Does CT Angiography Matter for Patients with Cervical Spine Injuries?

    PubMed

    Hagedorn, John C; Emery, Sanford E; France, John C; Daffner, Scott D

    2014-06-04

    Cervical injury can be associated with vertebral artery injury. This study was performed to determine the impact of computed tomography (CT) angiography of the head and neck on planning treatment of cervical spine fracture, if these tests were ordered appropriately, and to estimate cost and associated exposure to radiation and contrast medium. This retrospective review included all patients who underwent CT of the cervical spine and CT angiography of the head and neck from January 2010 to August 2011 at one institution. Patients were divided into those with and those without cervical spine fracture seen on CT of the cervical spine. We determined if the CT angiography of the head and neck was positive for vascular injury in the patients with a cervical fracture. Vascular injury treatment and alterations in surgical fracture treatment due to positive CT angiography of the head and neck were recorded. A scan was deemed appropriate if it had been ordered per established institutional protocol. Of the 381 patients who underwent CT angiography of the head and neck, 126 had a cervical injury. Sixteen of the CT angiography studies were appropriately ordered for non-spinal indications, and twenty-three were inappropriately ordered. The CT angiography was positive for one patient for whom the imaging was off protocol and one for whom the indication was non-spinal. Nineteen patients had positive CT angiography of the head and neck; no patient underwent surgical intervention for a vascular lesion. Eleven patients underwent surgical intervention for a cervical fracture; the operative plan was changed because of vascular injury in one case. The CT angiography was positive for eleven of forty-eight patients who had sustained a C2 fracture; this group accounted for eleven of the nineteen positive CT angiography studies. Noncontiguous injuries occurred in nineteen patients; three had positive CT angiography of the head and neck. The approximate charge for the CT angiography was

  13. Relationship of homocysteine levels with lumbar spine and femur neck BMD in postmenopausal women.

    PubMed

    Bahtiri, E; Islami, H; Rexhepi, S; Qorraj-Bytyqi, H; Thaçi, K; Thaçi, S; Karakulak, C; Hoxha, R

    2015-01-01

    The focus of several studies in recent years has been the association between increased plasma concentrations of homocysteine (Hcy), reduced bone mineral density and increased risk of bone fractures. Nevertheless, inconsistencies persist in the literature. Thus, the objective of this study was to investigate the possible relationship between serum Hcy and vitamin B12 status, and bone mineral density, on a group of post-menopausal women. One hundred thirty-nine postmenopausal women were recruited to enter this cross-sectional study. Bone mineral density (BMD) of total hip, femoral neck and lumbar spine was measured by dual-energy X-ray absorptiometry (DXA) and serum Hcy, vitamin B12, parathyroid hormone (PTH), total calcium and magnesium levels were determined. In addition, we investigated the relationship of Hcy and vitamin B12 and BMD using a meta-analysis approach. Serum Hcy levels were significantly higher in osteoporotic women when compared to other BMD groups, and were inversely related to lumbar spine BMD and femur neck BMD. Body mass index and serum Hcy levels were shown to be significant predictors of BMD at lumbar spine, femur neck and total hip. The performed meta-analysis showed that serum Hcy levels were significantly higher in osteoporotic subjects compared to normal BMD subjects. This study shows that Hcy status, but not vitamin B12 status, is associated with BMD in this cohort of postmenopausal women. We therefore confirm that high Hcy levels are an independent risk factor for osteoporosis. BMD evaluation in women at post menopause with high Hcy levels may be helpful in advising precautionary measures.

  14. Body Composition Comparison: Bioelectric Impedance Analysis with Dual-Energy X-Ray Absorptiometry in Adult Athletes

    ERIC Educational Resources Information Center

    Company, Joe; Ball, Stephen

    2010-01-01

    The primary purpose of this study was to investigate the accuracy of the DF50 (ImpediMed Ltd, Eight Mile Plains, Queensland, Australia) bioelectrical impedance analysis device using dual-energy x-ray absorptiometry as the criterion in two groups: endurance athletes and power athletes. The secondary purpose was to develop accurate body fat…

  15. Assessing Body Composition of Children and Adolescents Using Dual-Energy X-Ray Absorptiometry, Skinfolds, and Electrical Impedance

    ERIC Educational Resources Information Center

    Mooney, Angela; Kelsey, Laurel; Fellingham, Gilbert W.; George, James D.; Hager, Ron L.; Myrer, J. William; Vehrs, Pat R.

    2011-01-01

    To determine the validity and reliability of percent body fat estimates in 177 boys and 154 girls between 12-17 years of age, percent body fat was assessed once using dual-energy X-ray absorptiometry and twice using the sum of two skinfolds and three bioelectrical impedance analysis devices. The assessments were repeated on 79 participants on a…

  16. Nanoscale segregation of actin nucleation and elongation factors determines dendritic spine protrusion

    PubMed Central

    Chazeau, Anaël; Mehidi, Amine; Nair, Deepak; Gautier, Jérémie J; Leduc, Cécile; Chamma, Ingrid; Kage, Frieda; Kechkar, Adel; Thoumine, Olivier; Rottner, Klemens; Choquet, Daniel; Gautreau, Alexis; Sibarita, Jean-Baptiste; Giannone, Grégory

    2014-01-01

    Actin dynamics drive morphological remodeling of neuronal dendritic spines and changes in synaptic transmission. Yet, the spatiotemporal coordination of actin regulators in spines is unknown. Using single protein tracking and super-resolution imaging, we revealed the nanoscale organization and dynamics of branched F-actin regulators in spines. Branched F-actin nucleation occurs at the PSD vicinity, while elongation occurs at the tip of finger-like protrusions. This spatial segregation differs from lamellipodia where both branched F-actin nucleation and elongation occur at protrusion tips. The PSD is a persistent confinement zone for IRSp53 and the WAVE complex, an activator of the Arp2/3 complex. In contrast, filament elongators like VASP and formin-like protein-2 move outwards from the PSD with protrusion tips. Accordingly, Arp2/3 complexes associated with F-actin are immobile and surround the PSD. Arp2/3 and Rac1 GTPase converge to the PSD, respectively, by cytosolic and free-diffusion on the membrane. Enhanced Rac1 activation and Shank3 over-expression, both associated with spine enlargement, induce delocalization of the WAVE complex from the PSD. Thus, the specific localization of branched F-actin regulators in spines might be reorganized during spine morphological remodeling often associated with synaptic plasticity. PMID:25293574

  17. Preferential stabilization of newly formed dendritic spines in motor cortex during manual skill learning predicts performance gains, but not memory endurance.

    PubMed

    Clark, Taylor A; Fu, Min; Dunn, Andrew K; Zuo, Yi; Jones, Theresa A

    2018-07-01

    Previous findings that skill learning is associated with the formation and preferential stabilization of new dendritic spines in cortex have raised the possibility that this preferential stabilization is a mechanism for lasting skill memory. We investigated this possibility in adult mice using in vivo two-photon imaging to monitor spine dynamics on superficial apical dendrites of layer V pyramidal neurons in motor cortex during manual skill learning. Spine formation increased over the first 3 days of training on a skilled reaching task, followed by increased spine elimination. A greater proportion of spines formed during the first 3 training days were lost if training stopped after 3, compared with 15 days. However, performance gains achieved in 3 training days persisted, indicating that preferential new spine stabilization was non-essential for skill retention. Consistent with a role in ongoing skill refinement, the persistence of spines formed early in training strongly predicted performance improvements. Finally, while we observed no net spine density change on superficial dendrites, the density of spines on deeper apical branches of the same neuronal population was increased regardless of training duration, suggestive of a potential role in the retention of the initial skill memory. Together, these results indicate dendritic subpopulation-dependent variation in spine structural responses to skill learning, which potentially reflect distinct contributions to the refinement and retention of newly acquired motor skills. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Effectiveness of Treatment of Idiopathic Scoliosis by SpineCor Dynamic Bracing with Special Physiotherapy Programme in SpineCor System.

    PubMed

    Rożek, Karina; Potaczek, Tomasz; Zarzycka, Maja; Lipik, Ewa; Jasiewicz, Barbara

    2016-10-28

    The SpineCor dynamic brace for the treatment of idiopathic scoliosis is designed to maintain the correct position of the spine and a new movement strategy for 20 hours per day. The SpineCor exercise system intensifies and complements the brace treatment. This study evaluated the effectiveness of a comprehensive treatment of idiopathic scoliosis involving the SpineCor system. The study assessed a group of 40 patients (38 girls and 2 boys) with idiopathic scoliosis treated with the SpineCor brace. The average age at beginning of treatment was 13.1 yrs (10-15). Minimum treatment time was 18 months. 28 participants met the SRS criteria. Angles of the curve before and after bracing based on imaging studies were measured at the beginning and end of the treatment, analyzed and compared. Rehabilitation focused on teaching active corrective movement throughout the brace treatment. A control group was formed of 33 patients, including 21 meeting the SRS criteria, who used the SpineCor dynamic brace but did not participate in the associated exercise programme. Among patients from the exercise group who met the SRS criteria, 25% demonstrated reduced curve angles, 35.7% demonstrated curve progression and 39.3% showed stabilization (no change). Among patients meeting the SRS criteria from the control group, a decrease in curve angle was observed in 14.3% of the patients, curve progression in 57.1% and stabilization in 28.6%. 1. The addition of a dedicated physiotherapy programme to SpineCor dynamic bracing improves the chances of obtaining a positive outcome. 2. It is necessary to further analyse the course of the comprehensive treatment, also with regard to other types of braces and kinesiotherapy programmes.

  19. Evidence-based medicine in metastatic spine disease.

    PubMed

    Dea, Nicolas; Fisher, Charles G

    2014-06-01

    Treatment modalities for metastatic spine disease have significantly expanded over the last two decades. This expansion occurred in many different fields. Improvement in surgical techniques and instrumentation now allow the oncologic spine surgeons to effectively circumferentially decompress the neural elements without compromising stability. Percutaneous techniques, both vertebral augmentation and pre-operative endovascular embolization procedures, also greatly benefit patients suffering from spinal column metastasis. Imaging technology advances has contributed to better pre-operative planning and the development of highly conformational radiation techniques, thus permitting the delivery of high-dose radiation to tumors, while avoiding radiotoxicity to the spinal cord and other vital structures. These new developments, combined with evidence-based stability and disease-specific quality of life scores now allow not only better treatment, but also a solid foundation for high-quality research. Spine oncology literature currently suffers from a lack of high-quality evidence due to low prevalence of the disease and complex methodological issues. However, when following evidence-based medicine principles, which incorporate best available evidence, clinical expertise and patient preference, sound, evidence-based recommendations can be made regarding the abovementioned treatment modalities.

  20. Fluoroscopically Guided Epidural Injections of the Cervical and Lumbar Spine.

    PubMed

    Shim, Euddeum; Lee, Joon Woo; Lee, Eugene; Ahn, Joong Mo; Kang, Yusuhn; Kang, Heung Sik

    2017-01-01

    Advances in imaging and the development of injection techniques have enabled spinal intervention to become an important tool in managing chronic spinal pain. Epidural steroid injection (ESI) is one of the most widely used spinal interventions; it directly delivers drugs into the epidural space to relieve pain originating from degenerative spine disorders-central canal stenoses and neural foraminal stenoses-or disk herniations. Knowledge of the normal anatomy of the epidural space is essential to perform an effective and safe ESI and to recognize possible complications. Although computed tomographic (CT) or combined CT-fluoroscopic guidance has been increasingly used in ESI, conventional fluoroscopic guidance is generally performed. In ESI, drugs are delivered into the epidural space by interlaminar or transforaminal routes in the cervical spine or by interlaminar, transforaminal, or caudal routes in the lumbar spine. Epidurography is usually performed before drug delivery to verify the proper position of the needle in the epidural space. A small amount of contrast agent is injected with fluoroscopic guidance. Familiarity with the findings on a typical "true" epidurogram (demonstrating correct needle placement in the epidural space) permits proper performance of ESI. Findings on "false" epidurograms (demonstrating incorrect needle placement) include muscular staining and evidence of intravascular injection, inadvertent facet joint injection, dural puncture, subdural injection, and intraneural or intradiscal injection. © RSNA, 2016 An earlier incorrect version of this article appeared online. This article was corrected on December 22, 2016.

  1. Dimensional coordinate measurements: application in characterizing cervical spine motion

    NASA Astrophysics Data System (ADS)

    Zheng, Weilong; Li, Linan; Wang, Shibin; Wang, Zhiyong; Shi, Nianke; Xue, Yuan

    2014-06-01

    Cervical spine as a complicated part in the human body, the form of its movement is diverse. The movements of the segments of vertebrae are three-dimensional, and it is reflected in the changes of the angle between two joint and the displacement in different directions. Under normal conditions, cervical can flex, extend, lateral flex and rotate. For there is no relative motion between measuring marks fixed on one segment of cervical vertebra, the cervical vertebrae with three marked points can be seen as a body. Body's motion in space can be decomposed into translational movement and rotational movement around a base point .This study concerns the calculation of dimensional coordinate of the marked points pasted to the human body's cervical spine by an optical method. Afterward, these measures will allow the calculation of motion parameters for every spine segment. For this study, we choose a three-dimensional measurement method based on binocular stereo vision. The object with marked points is placed in front of the CCD camera. Through each shot, we will get there two parallax images taken from different cameras. According to the principle of binocular vision we can be realized three-dimensional measurements. Cameras are erected parallelly. This paper describes the layout of experimental system and a mathematical model to get the coordinates.

  2. Malpractice litigation following spine surgery.

    PubMed

    Daniels, Alan H; Ruttiman, Roy; Eltorai, Adam E M; DePasse, J Mason; Brea, Bielinsky A; Palumbo, Mark A

    2017-10-01

    OBJECTIVE Adverse events related to spine surgery sometimes lead to litigation. Few studies have evaluated the association between spine surgical complications and medical malpractice proceedings, outcomes, and awards. The aim of this study was to identify the most frequent causes of alleged malpractice in spine surgery and to gain insight into patient demographic and clinical characteristics associated with medical negligence litigation. METHODS A search for "spine surgery" spanning February 1988 to May 2015 was conducted utilizing the medicolegal research service VerdictSearch (ALM Media Properties, LLC). Demographic data for the plaintiff and defendant in addition to clinical data for the procedure and legal outcomes were examined. Spinal cord injury, anoxic/hypoxic brain injury, and death were classified as catastrophic complications; all other complications were classified as noncatastrophic. Both chi-square and t-tests were used to evaluate the effect of these variables on case outcomes and awards granted. RESULTS A total of 569 legal cases were examined; 335 cases were excluded due to irrelevance or insufficient information. Of the 234 cases included in this investigation, 54.2% (127 cases) resulted in a defendant ruling, 26.1% (61) in a plaintiff ruling, and 19.6% (46) in a settlement. The awards granted for plaintiff rulings ranged from $134,000 to $38,323,196 (mean $4,045,205 ± $6,804,647). Awards for settlements ranged from $125,000 to $9,000,000 (mean $1,930,278 ± $2,113,593), which was significantly less than plaintiff rulings (p = 0.022). Compared with cases without a delay in diagnosis of the complication, the cases with a diagnostic delay were more likely to result in a plaintiff verdict or settlement (42.9% vs 72.7%, p = 0.007) than a defense verdict, and were more likely to settle out of court (17.5% vs 40.9%, p = 0.008). Similarly, compared with cases without a delay in treatment of the complication, those with a therapeutic delay were more

  3. Correlations between the MR Diffusion-weighted Image (DWI) and the bone mineral density (BMD) as a function of the soft tissue thickness-focus on phantom and patient

    NASA Astrophysics Data System (ADS)

    Kim, Myung-Sam; Cho, Jae-Hwan; Lee, Hae-Kag; Lee, Sang-Jeong; Park, Cheol-Soo; Dong, Kyung-Rae; Park, Yong-Soon; Chung, Woon-Kwan; Lee, Jong-Woong; Kim, Ho-Sung; Kim, Eun-Hye; Kweon, Dae Cheol; Yeo, Hwa-Yeon

    2013-02-01

    In this study we used lumbar phantoms to determine if the BMD (bone mineral density) changes when only the thickness of soft tissue is increased. Second, we targeted osteoporosis patients to analyze the dependences of the changes in the SNR (signal-to-noise ratio) and the ADC (apparent diffusion coefficient) on changes in T-score. We used a bone mineral densitometer, phantoms such as an aluminum spine phantom (ASP), a Hologic spine phantom (HSP), and a European spine phantom (ESP), five sheets of acrylic panel, and a water bath to study the effects of changes in the thickness of soft tissue. First, we measured the ASP, the HSP and the ESP. For the measurement of the ASP, we filled it with water to increase the height by 0.5 cm starting from the baseline height. We then did three measurements for each height. For the measurements of the HSP and the ESP, we placed an acrylic panel on the phantom and then did three measurements at each height. We used the ASP to calculate the degree of precision of the standard mode and the thick mode at the maximum height of the water bath. To assess the degree of precision in the measurements of the three types of phantoms, we calculated precision errors and analyzed the correlation between the change in the thickness of soft tissue and the variables of the BMD. Using DWIs (diffusion weighted images), we targeted 30 healthy persons without osteoporosis and 30 patients with a finding of osteoporosis and measured the T-scores for the L1 — L4 (lumbar spine) segments of by the spine using the dual-energy X-ray absorptiometry (DXA) before classifying the measurement at each part of the spine as osteopenia or osteoporosis. We measured the signal intensity on all four parts of L1-L4 in the DWIs obtained using a 1.5T MR scanner and measured the ADC in the ADC map image. We compared changes in the SNR and the ADC for each group. The study results confirmed that an increase in the thickness of the soft tissue had a significant correlation

  4. Fungal Infections of the Spine.

    PubMed

    Ganesh, Devin; Gottlieb, Jonathan; Chan, Sherilynn; Martinez, Octavio; Eismont, Frank

    2015-06-15

    Review of the literature. To retrospectively examine the frequency of published fungal infections by species and the treatment algorithms used to eradicate the disease. Fungal infections of the spine present unique challenges to the modern multispecialty treatment team. Although rare in comparison with bacterial infections, fungal infections have been increasing in incidence over the past several decades. Evidences-based practice is limited to referencing smaller case series. MEDLINE, Scopus, and EMBASE searches were carried out by one of the authors as well as by the research desk at the University of Miami/Calder Memorial Library. We included peer-reviewed articles published between 1948 and September 2010; case reports, series, and reviews were all examined and compiled into a database. A total of 130 articles, representing 157 cases, were included in the review. Aspergillus (60 cases, 38.2% of the total) and Candida species (36 cases, 22.9% of the total) were the 2 most common organisms. Surgery was associated with a greater survival rate than medical management alone in patients with Aspergillus (26.9% mortality in surgical patients; 60% in medically treated patients) and Candida (0% vs. 28.6%). Overall mortality was 19.3%. The overall recurrence rate was 7.4%. Amphotericin use was associated with a higher mortality rate than azoles. Aspergillus is the most common published pathogen in fungal infections of the spine. Recent publications depicting the use of newer antifungal medications such as azoles report higher survival rates. Surgically treated patients in combination with antifungal therapy showed highest frequencies of patient survival in Aspergillus and Candida infections. 3.

  5. Harvey Cushing, the Spine Surgeon

    PubMed Central

    Bydon, Ali; Dasenbrock, Hormuzdiyar H.; Pendleton, Courtney; McGirt, Matthew J.; Gokaslan, Ziya L.; Quinones-Hinojosa, Alfredo

    2015-01-01

    Study Design Review of historical archival records. Objective Describe Harvey Cushing's patients with spinal pathology. Summary of Background Data Harvey Cushing was a pioneer of modern surgery but his work on spine remains largely unknown. Methods Review of the Chesney Medical Archives of the Johns Hopkins Hospital from 1896 to 1912. Results This is the first time that Cushing's spinal cases while he was at the Johns Hopkins Hospital, including those with Pott disease, have been described. Cushing treated three young men with psoas abscesses secondary to Pott disease during his residency: he drained the abscesses, debrided any accompanying necrotic vertebral bodies, irrigated the cavity with salt, and left the incision open to close by secondary intention. Although Cushing used Koch's “tuberculin therapy” (of intravenous administration of isolated tubercular bacilli) in one patient, he did not do so in the other two, likely because of the poor response of this first patient. Later in his tenure, Cushing performed a laminectomy on a patient with kyphosis and paraplegia secondary to Pott disease. Conclusion These cases provide a view of Cushing early in his career, pointing to the extraordinary degree of independence that he had during his residency under William Steward Halsted; these cases may have been important in the surgical upbringing both of Cushing and his coresident, William Stevenson Baer, who became the first professor of Orthopedics at Johns Hopkins Hospital. At the turn of the last century, Pott disease was primarily treated by immobilization with bed rest, braces, and plaster-of-paris jackets; some surgeons also employed gradual correction of the deformity by hyperextension. Patients who failed a trial of conservative therapy (of months to years) were treated with a laminectomy. However, the limitations of these strategies led to the development of techniques that form the basis of contemporary spine surgery—instrumentation and fusion. PMID

  6. Electromyographic monitoring and its anatomical implications in minimally invasive spine surgery.

    PubMed

    Uribe, Juan S; Vale, Fernando L; Dakwar, Elias

    2010-12-15

    Literature review. The objective of this article is to examine current intraoperative electromyography (EMG) neurophysiologic monitoring methods and their application in minimally invasive techniques. We will also discuss the recent application of EMG and its anatomic implications to the minimally invasive lateral transpsoas approach to the spine. Minimally invasive techniques require that the same goals of surgery be achieved, with the hope of decreased morbidity to the patient. Unlike standard open procedures, direct visualization of the anatomy is decreased. To increase the safety of minimally invasive spine surgery, neurophysiological monitoring techniques have been developed. Review of the literature was performed using the National Center for Biotechnology Information databases using PUBMED/MEDLINE. All articles in the English language discussing the use of intraoperative EMG monitoring and minimally invasive spine surgery were reviewed. The role of EMG monitoring in special reference to the minimally invasive lateral transpsoas approach is also described. In total, 76 articles were identified that discussed the role of neuromonitoring in spine surgery. The majority of articles on EMG and spine surgery discuss the use of intraoperative neurophysiological monitoring (IOM) for safe and accurate pedicle screw placement. In general, there is a paucity of literature that pertains to intraoperative EMG neuromonitoring and minimally invasive spine surgery. Recently, EMG has been used during minimally invasive lateral transpsoas approach to the lumbar spine for interbody fusion. The addition of EMG to the lateral approach has contributed to decrease the complication rate from 30% to less than 1%. In minimally invasive approaches to the spine, the use of EMG IOM might provide additional safety, such as percutaneous pedicle screw placement, where visualization is limited compared with conventional open procedures. In addition to knowledge of the anatomy and image

  7. Degenerative Changes of Spine in Helicopter Pilots

    PubMed Central

    Byeon, Joo Hyeon; Kim, Jung Won; Jeong, Ho Joong; Sim, Young Joo; Kim, Dong Kyu; Choi, Jong Kyoung; Im, Hyoung June

    2013-01-01

    Objective To determine the relationship between whole body vibration (WBV) induced helicopter flights and degenerative changes of the cervical and lumbar spine. Methods We examined 186 helicopter pilots who were exposed to WBV and 94 military clerical workers at a military hospital. Questionnaires and interviews were completed for 164 of the 186 pilots (response rate, 88.2%) and 88 of the 94 clerical workers (response rate, 93.6%). Radiographic examinations of the cervical and the lumbar spines were performed after obtaining informed consent in both groups. Degenerative changes of the cervical and lumbar spines were determined using four radiographs per subject, and diagnosed by two independent, blinded radiologists. Results There was no significant difference in general and work-related characteristics except for flight hours and frequency between helicopter pilots and clerical workers. Degenerative changes in the cervical spine were significantly more prevalent in the helicopter pilots compared with control group. In the cervical spine multivariate model, accumulated flight hours (per 100 hours) was associated with degenerative changes. And in the lumbar spine multivariate model, accumulated flight hours (per 100 hours) and age were associated with degenerative changes. Conclusion Accumulated flight hours were associated with degenerative changes of the cervical and lumbar spines in helicopter pilots. PMID:24236259

  8. Most Cited Publications in Cervical Spine Surgery

    PubMed Central

    Brooks, Francis; Sandler, Simon; Yau, Yun-Hom; Selby, Michael; Freeman, Brian

    2017-01-01

    Purpose The purpose of this study is to perform a citation analysis on the most frequently cited articles in the topic of cervical spine surgery and report on the top 100 most cited publication in this topic. Methods We used the Thomson Reuters Web of Science to search citations of all articles from 1945 to 2015 relevant to cervical spine surgery and ranked them according to the number of citations. The 100 most cited articles that matched the search criteria were further analyzed by number of citations, first author, journal, year of publication, country and institution of origin. Results The top 100 cited articles in the topic of cervical spine surgery were published from 1952-2011. The number of citations ranged from 106 times for the 100th paper to 1206 times for the top paper. The decade of 1990-1999 saw the most publications. The Journal of Spine published the most articles, followed by Journal of Bone and Joint Surgery America. Investigators from America authored the most papers and The University of California contributed the most publications. Cervical spine fusion was the most common topic published with 36 papers, followed by surgical technique and trauma. Conclusion This article identifies the 100 most cited articles in cervical spine surgery. It has provided insight to the history and development in cervical spine surgery and many of which have shaped the way we practice today. PMID:28765803

  9. The profit motive and spine surgery.

    PubMed

    Weiner, Bradley K; Levi, Benjamin H

    2004-11-15

    The profit motive and market medicine have had a significant impact on clinical practice and research in the field of spine surgery. An overview of current concerns is presented. The objective of this study was to provide those involved in the study and treatment of spinal disorders with a critical overview of the effects of the profit motive on our practices. Historically, the profit motive has been viewed as eroding the standards of spine surgery, encouraging surgeons to operate aggressively and researchers to bias their results. Although there are legitimate concerns regarding the role played by such market forces, the profit motive exerts several quite positive effects on spine surgery as well. Negative and positive aspects of the profit motive in spine surgery are explored along with alternative approaches. The profit motive in spine surgery can result in unnecessary surgery, as well as the push to market of unproven technologies. Yet, without a robust profit motive, it is unclear where sufficient funding could be found to support research and education, and to underwrite the advancement of new technologies. The profit motive significantly influences the way we practice and conduct research in spine surgery. To minimize the negative aspects of the profit motive, spine surgeons and researchers must refrain from being used by companies to rush products to market and/or compromising patient care out of self-interest.

  10. The sensitivity and negative predictive value of a pediatric cervical spine clearance algorithm that minimizes computerized tomography.

    PubMed

    Arbuthnot, Mary; Mooney, David P

    2017-01-01

    It is crucial to identify cervical spine injuries while minimizing ionizing radiation. This study analyzes the sensitivity and negative predictive value of a pediatric cervical spine clearance algorithm. We performed a retrospective review of all children <21years old who were admitted following blunt trauma and underwent cervical spine clearance utilizing our institution's cervical spine clearance algorithm over a 10-year period. Age, gender, International Classification of Diseases 9th Edition diagnosis codes, presence or absence of cervical collar on arrival, Injury Severity Score, and type of cervical spine imaging obtained were extracted from the trauma registry and electronic medical record. Descriptive statistics were used and the sensitivity and negative predictive value of the algorithm were calculated. Approximately 125,000 children were evaluated in the Emergency Department and 11,331 were admitted. Of the admitted children, 1023 patients arrived in a cervical collar without advanced cervical spine imaging and were evaluated using the cervical spine clearance algorithm. Algorithm sensitivity was 94.4% and the negative predictive value was 99.9%. There was one missed injury, a spinous process tip fracture in a teenager maintained in a collar. Our algorithm was associated with a low missed injury rate and low CT utilization rate, even in children <3years old. IV. Published by Elsevier Inc.

  11. Cervical spine injury from gunshot wounds.

    PubMed

    Beaty, Narlin; Slavin, Justin; Diaz, Cara; Zeleznick, Kyle; Ibrahimi, David; Sansur, Charles A

    2014-09-01

    Gunshot wounds (GSWs) to the cervical spine have been examined in a limited number of case series, and operative management of this traumatic disease has been sparsely discussed. The current literature supports and the authors hypothesize that patients without neurological deficit need neither surgical fusion nor decompression. Patients with GSWs and neurological deficits, however, pose a greater management challenge. The authors have compiled the experience of the R Adams Cowley Shock Trauma Center in Baltimore, Maryland, over the past 12 years, creating the largest series of such injuries, with a total number of 40 civilian patients needing neurosurgical evaluation. The current analysis examines presenting bone injury, surgical indication, presenting neurological examination, and neurological outcome. In this study, the authors characterize the incidence, severity, and recovery potential of cervical GSWs. The rate of unstable fractures requiring surgical intervention is documented. A detailed discussion of surgical indications with a treatment algorithm for cervical instability is offered. A total of 144 cervical GSWs were retrospectively reviewed. Of these injuries, 40 had documented neurological deficits. No neurosurgical consultation was requested for patients without deficit. Epidemiological and clinical information was collected on patients with neurological deficit, including age, sex, timing, indication, type of surgery, initial examination after resuscitation, follow-up examination, and imaging data. Twenty-eight patients (70%) presented with complete neurological deficits and 12 patients (30%) presented with incomplete injuries. Fourteen (35%) of the 40 patients underwent neurosurgical intervention. Twelve patients (30%) required intervention for cervical instability. Seven patients required internal fixation involving 4 anterior fusions, 2 posterior fusions, and 1 combined approach. Five patients were managed with halo immobilization. Two patients

  12. Instrumentation and fusion for congenital spine deformities.

    PubMed

    Hedequist, Daniel J

    2009-08-01

    A retrospective clinical review. To review the use of modern instrumentation of the spine for congenital spinal deformities. Spinal instrumentation has evolved since the advent of the Harrington rod. There is a paucity of literature, which discusses the use of modern spinal instrumentation in congenital spine deformity cases. This review focuses on modern instrumentation techniques for congenital scoliosis and kyphosis. A systematic review was performed of the literature to discuss spinal implant use for congenital deformities. Spinal instrumentation may be safely and effectively used in cases of congenital spinal deformity. Spinal surgeons taking care of children with congenital spine deformities need to be trained in all aspects of modern spinal instrumentation.

  13. 49 CFR 572.85 - Lumbar spine flexure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) of this section, the lumbar spine assembly shall flex by an amount that permits the thoracic spine to... to the thoracic spine box. Apply the force at any torso deflection rate between 0.5 and 1.5 degrees... 49 Transportation 7 2011-10-01 2011-10-01 false Lumbar spine flexure. 572.85 Section 572.85...

  14. Dendritic spine dynamics leading to spine elimination after repeated inductions of LTD

    PubMed Central

    Hasegawa, Sho; Sakuragi, Shigeo; Tominaga-Yoshino, Keiko; Ogura, Akihiko

    2015-01-01

    Memory is fixed solidly by repetition. However, the cellular mechanism underlying this repetition-dependent memory consolidation/reconsolidation remains unclear. In our previous study using stable slice cultures of the rodent hippocampus, we found long-lasting synaptic enhancement/suppression coupled with synapse formation/elimination after repeated inductions of chemical LTP/LTD, respectively. We proposed these phenomena as useful model systems for analyzing repetition-dependent memory consolidation. Recently, we analyzed the dynamics of dendritic spines during development of the enhancement, and found that the spines increased in number following characteristic stochastic processes. The current study investigates spine dynamics during the development of the suppression. We found that the rate of spine retraction increased immediately leaving that of spine generation unaltered. Spine elimination occurred independent of the pre-existing spine density on the dendritic segment. In terms of elimination, mushroom-type spines were not necessarily more stable than stubby-type and thin-type spines. PMID:25573377

  15. Dendritic spine dysgenesis in Rett syndrome

    PubMed Central

    Xu, Xin; Miller, Eric C.; Pozzo-Miller, Lucas

    2014-01-01

    Spines are small cytoplasmic extensions of dendrites that form the postsynaptic compartment of the majority of excitatory synapses in the mammalian brain. Alterations in the numerical density, size, and shape of dendritic spines have been correlated with neuronal dysfunction in several neurological and neurodevelopmental disorders associated with intellectual disability, including Rett syndrome (RTT). RTT is a progressive neurodevelopmental disorder associated with intellectual disability that is caused by loss of function mutations in the transcriptional regulator methyl CpG-binding protein 2 (MECP2). Here, we review the evidence demonstrating that principal neurons in RTT individuals and Mecp2-based experimental models exhibit alterations in the number and morphology of dendritic spines. We also discuss the exciting possibility that signaling pathways downstream of brain-derived neurotrophic factor (BDNF), which is transcriptionally regulated by MeCP2, offer promising therapeutic options for modulating dendritic spine development and plasticity in RTT and other MECP2-associated neurodevelopmental disorders. PMID:25309341

  16. San Pablo Avenue Green Stormwater Spine

    EPA Pesticide Factsheets

    Information about the SFBWQP San Pablo Avenue Green Stormwater Spine Project project, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

  17. Accountable disease management of spine pain.

    PubMed

    Smith, Matthew J

    2011-09-01

    The health care landscape has changed with new legislation addressing the unsustainable rise in costs in the US system. Low-value service lines caring for expensive chronic conditions have been targeted for reform; for better or worse, the treatment of spine pain has been recognized as a representative example. Examining the Patient Protection and Affordable Care Act and existing pilot studies can offer a preview of how chronic care of spine pain will be sustained. Accountable care in an organization capable of collecting, analyzing, and reporting clinical data and operational compliance is forthcoming. Interdisciplinary spine pain centers integrating surgical and medical management, behavioral medicine, physical reconditioning, and societal reintegration represent the model of high-value care for patients with chronic spine pain. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Safe cervical spine clearance in adult obtunded blunt trauma patients on the basis of a normal multidetector CT scan--a meta-analysis and cohort study.

    PubMed

    Raza, Mushahid; Elkhodair, Samer; Zaheer, Asif; Yousaf, Sohail

    2013-11-01

    A true gold standard to rule out a significant cervical spine injury in subset of blunt trauma patients with altered sensorium is still to be agreed upon. The objective of this study is to determine whether in obtunded adult patients with blunt trauma, a clinically significant injury to the cervical spine be ruled out on the basis of a normal multidetector cervical spine computed tomography. Comprehensive database search was conducted to include all the prospective and retrospective studies on blunt trauma patients with altered sensorium undergoing cervical spine multidetector CT scan as core imaging modality to "clear" the cervical spine. The studies used two main gold standards, magnetic resonance imaging of the cervical spine and/or prolonged clinical follow-up. The data was extracted to report true positive, true negatives, false positives and false negatives. Meta-analysis of sensitivity, specificity, negative and positive predictive values was performed using Meta Analyst Beta 3.13 software. We also performed a retrospective investigation comparing a robust clinical follow-up and/or cervical spine MR findings in 53 obtunded blunt trauma patients, who previously had undergone a normal multidetector CT scan of the cervical spine reported by a radiologist. A total of 10 studies involving 1850 obtunded blunt trauma patients with initial cervical spine CT scan reported as normal were included in the final meta-analysis. The cumulative negative predictive value and specificity of cervical spine CT of the ten studies was 99.7% (99.4-99.9%, 95% confidence interval). The positive predictive value and sensitivity was 93.7% (84.0-97.7%, 95% confidence interval). In the retrospective review of our obtunded blunt trauma patients, none was later diagnosed to have significant cervical spine injury that required a change in clinical management. In a blunt trauma patient with altered sensorium, a normal cervical spine CT scan is conclusive to safely rule out a clinically

  19. Cervical spine injuries in pediatric patients.

    PubMed

    Platzer, Patrick; Jaindl, Manuela; Thalhammer, Gerhild; Dittrich, Stefan; Kutscha-Lissberg, Florian; Vecsei, Vilmos; Gaebler, Christian

    2007-02-01

    Cervical spine injuries are uncommon in pediatric trauma patients. Previous studies were often limited by the small numbers of patients available for evaluation. The aim of this study was to determine the incidence and characteristics of pediatric cervical spine injuries at this Level 1 trauma center and to review the authors' experiences with documented cases. This study retrospectively analyzed the clinical records of all pediatric trauma patients with skeletal and/or nonskeletal injuries of the spine that were admitted to this Level 1 trauma center between 1980 and 2004. Those with significant injuries of the cervical spine were identified and included in this study. Pediatric patients were defined as patients younger than the age of 17 years. In addition, they were stratified by age into two study groups: group A included patients aged 8 years or fewer and group B contained patients from the ages of 9 to 16 years. We found 56 pediatric patients with injuries of the cervical spine that met criteria for inclusion. Thirty-one female and 25 male patients with an average age of 8.9 years (range, 1-16 years) sustained significant skeletal and/or nonskeletal injuries of the cervical spine and were entered in this study. Thirty patients (54%) were aged 8 years or fewer and entered into study group A, whereas 26 patients (46%) from the ages of 9 to 16 met criteria for inclusion in study group B. An analysis of data revealed that younger patients (group A) showed significantly more injuries of the upper cervical spine, whereas older children (group B) sustained significantly more injuries of the lower level. Spinal cord injuries without radiographic findings were only found in study group A. In addition, younger children were more likely injured by motor vehicle crashes, whereas older children more commonly sustained C-spine injuries during sports activities. Two-thirds of our patients showed neurologic deficits, and the overall mortality was 28%. The results of our

  20. Spine device clinical trials: design and sponsorship.

    PubMed

    Cher, Daniel J; Capobianco, Robyn A

    2015-05-01

    Multicenter prospective randomized clinical trials represent the best evidence to support the safety and effectiveness of medical devices. Industry sponsorship of multicenter clinical trials is purported to lead to bias. To determine what proportion of spine device-related trials are industry-sponsored and the effect of industry sponsorship on trial design. Analysis of data from a publicly available clinical trials database. Clinical trials of spine devices registered on ClinicalTrials.gov, a publicly accessible trial database, were evaluated in terms of design, number and location of study centers, and sample size. The relationship between trial design characteristics and study sponsorship was evaluated using logistic regression and general linear models. One thousand six hundred thrity-eight studies were retrieved from ClinicalTrials.gov using the search term "spine." Of the 367 trials that focused on spine surgery, 200 (54.5%) specifically studied devices for spine surgery and 167 (45.5%) focused on other issues related to spine surgery. Compared with nondevice trials, device trials were far more likely to be sponsored by the industry (74% vs. 22.2%, odds ratio (OR) 9.9 [95% confidence interval 6.1-16.3]). Industry-sponsored device trials were more likely multicenter (80% vs. 29%, OR 9.8 [4.8-21.1]) and had approximately four times as many participating study centers (p<.0001) and larger sample sizes. There were very few US-based multicenter randomized trials of spine devices not sponsored by the industry. Most device-related spine research is industry-sponsored. Multicenter trials are more likely to be industry-sponsored. These findings suggest that previously published studies showing larger effect sizes in industry-sponsored vs. nonindustry-sponsored studies may be biased as a result of failure to take into account the marked differences in design and purpose. Copyright © 2015 Elsevier Inc. All rights reserved.