Science.gov

Sample records for sclerosis lesion detection

  1. detecting multiple sclerosis lesions with a fully bioinspired visual attention model

    NASA Astrophysics Data System (ADS)

    Villalon-Reina, Julio; Gutierrez-Carvajal, Ricardo; Thompson, Paul M.; Romero-Castro, Eduardo

    2013-11-01

    The detection, segmentation and quantification of multiple sclerosis (MS) lesions on magnetic resonance images (MRI) has been a very active field for the last two decades because of the urge to correlate these measures with the effectiveness of pharmacological treatment. A myriad of methods has been developed and most of these are non specific for the type of lesions and segment the lesions in their acute and chronic phases together. On the other hand, radiologists are able to distinguish between several stages of the disease on different types of MRI images. The main motivation of the work presented here is to computationally emulate the visual perception of the radiologist by using modeling principles of the neuronal centers along the visual system. By using this approach we are able to detect the lesions in the majority of the images in our population sample. This type of approach also allows us to study and improve the analysis of brain networks by introducing a priori information.

  2. Fully automatic detection of deep white matter T1 hypointense lesions in multiple sclerosis

    NASA Astrophysics Data System (ADS)

    Spies, Lothar; Tewes, Anja; Suppa, Per; Opfer, Roland; Buchert, Ralph; Winkler, Gerhard; Raji, Alaleh

    2013-12-01

    A novel method is presented for fully automatic detection of candidate white matter (WM) T1 hypointense lesions in three-dimensional high-resolution T1-weighted magnetic resonance (MR) images. By definition, T1 hypointense lesions have similar intensity as gray matter (GM) and thus appear darker than surrounding normal WM in T1-weighted images. The novel method uses a standard classification algorithm to partition T1-weighted images into GM, WM and cerebrospinal fluid (CSF). As a consequence, T1 hypointense lesions are assigned an increased GM probability by the standard classification algorithm. The GM component image of a patient is then tested voxel-by-voxel against GM component images of a normative database of healthy individuals. Clusters (≥0.1 ml) of significantly increased GM density within a predefined mask of deep WM are defined as lesions. The performance of the algorithm was assessed on voxel level by a simulation study. A maximum dice similarity coefficient of 60% was found for a typical T1 lesion pattern with contrasts ranging from WM to cortical GM, indicating substantial agreement between ground truth and automatic detection. Retrospective application to 10 patients with multiple sclerosis demonstrated that 93 out of 96 T1 hypointense lesions were detected. On average 3.6 false positive T1 hypointense lesions per patient were found. The novel method is promising to support the detection of hypointense lesions in T1-weighted images which warrants further evaluation in larger patient samples.

  3. Robust detection of multiple sclerosis lesions from intensity-normalized multi-channel MRI

    NASA Astrophysics Data System (ADS)

    Karpate, Yogesh; Commowick, Olivier; Barillot, Christian

    2015-03-01

    Multiple sclerosis (MS) is a disease with heterogeneous evolution among the patients. Quantitative analysis of longitudinal Magnetic Resonance Images (MRI) provides a spatial analysis of the brain tissues which may lead to the discovery of biomarkers of disease evolution. Better understanding of the disease will lead to a better discovery of pathogenic mechanisms, allowing for patient-adapted therapeutic strategies. To characterize MS lesions, we propose a novel paradigm to detect white matter lesions based on a statistical framework. It aims at studying the benefits of using multi-channel MRI to detect statistically significant differences between each individual MS patient and a database of control subjects. This framework consists in two components. First, intensity standardization is conducted to minimize the inter-subject intensity difference arising from variability of the acquisition process and different scanners. The intensity normalization maps parameters obtained using a robust Gaussian Mixture Model (GMM) estimation not affected by the presence of MS lesions. The second part studies the comparison of multi-channel MRI of MS patients with respect to an atlas built from the control subjects, thereby allowing us to look for differences in normal appearing white matter, in and around the lesions of each patient. Experimental results demonstrate that our technique accurately detects significant differences in lesions consequently improving the results of MS lesion detection.

  4. Detection of multiple sclerosis lesions in MRIs with an SVM classifier

    NASA Astrophysics Data System (ADS)

    D'Addabbo, Annarita; Ancona, Nicola; Blonda, Palma N.; De Blasi, Roberto A.

    2003-05-01

    The purpose of this paper is to test the effectiveness of a Support Vector Machine (SVM) classifier, with gaussian kernel function, in the automatic detection of small lesions from Magnetic Resonance Images (MRIs) of a patientt affected by multiple sclerosis. The data set consists of Proton Density, T2 (the spin-spin relaxation time) Spin-Echo images and a three-dimensional T1-weighted gradient echo sequence, called Magnetization-Prepared RApid Gradient Echo, that can be generated from contiguous and very thin sections, allowing detection of small lesions typically affected by partial volume effects and intersection gaps in T1 weighted Spin-Echol sequences. In this context of classification, SVM with Gaussian kernel function exhibited a good classification accuracy, higher than accuracies obtained, on the same data set, with a traditional RBF, confirming its high generalization capability and its effectiveness when applied to low-dimensional multi-spectral images.

  5. Improved CSF classification and lesion detection in MR brain images with multiple sclerosis

    NASA Astrophysics Data System (ADS)

    Wolff, Yulian; Miron, Shmuel; Achiron, Anat; Greenspan, Hayit

    2007-03-01

    The study deals with the challenging task of automatic segmentation of MR brain images with multiple sclerosis lesions (MSL). Multi-Channel data is used, including "fast fluid attenuated inversion recovery" (fast FLAIR or FF), and statistical modeling tools are developed, in order to improve cerebrospinal fluid (CSF) classification and to detect MSL. Two new concepts are proposed for use within an EM framework. The first concept is the integration of prior knowledge as it relates to tissue behavior in different MRI modalities, with special attention given to the FF modality. The second concept deals with running the algorithm on a subset of the input that is most likely to be noise- and artifact-free data. This enables a more reliable learning of the Gaussian mixture model (GMM) parameters for brain tissue statistics. The proposed method focuses on the problematic CSF intensity distribution, which is a key to improved overall segmentation and lesion detection. A level-set based active contour stage is performed for lesion delineation, using gradient and shape properties combined with previously learned region intensity statistics. In the proposed scheme there is no need for preregistration of an atlas, a common characteristic in brain segmentation schemes. Experimental results on real data are presented.

  6. Automated detection and quantification of multiple sclerosis lesions in MR volumes of the brain

    NASA Astrophysics Data System (ADS)

    Mitchell, Ross; Karlik, Stephen J.; Lee, Donald H.; Fenster, Aaron

    1992-06-01

    MRI is the principle technique for the diagnosis of multiple sclerosis. However, manually quantifying the number and extent of lesions in MR images is arduous. Therefore, we are developing a computerized 3-D quantitative system to determine the lesions' extent and their changes in time. Our system uses proton density (PD) and T2 weighted MR volumes. A 2-D histogram showing the frequency of voxels with particular PD and T2 weighted intensities reveals that white matter, grey matter (GM), and cerebro-spinal fluid voxels correspond to distinct clusters in this histogram and can be classified on this basis. However, many true MS lesion voxels have PD and T2 weighted intensities similar to GM. Therefore, on the basis of location in the histogram alone, it is difficult to differentiate all lesions voxels from GM voxels. However, some lesions have a distinctive `peak' in the 2-D histogram which can be used to identify them successfully. Using this system it is possible to assess and monitor changes in time for these lesions. To demonstrate this ability, four MR examinations of a single chronic-progressive MS patient obtained over a 510 day period were analyzed using our system. Three-dimensional volume rendering and measurement of the results clearly shows changes in lesion shape, position, and size.

  7. IMaGe: Iterative Multilevel Probabilistic Graphical Model for Detection and Segmentation of Multiple Sclerosis Lesions in Brain MRI.

    PubMed

    Subbanna, Nagesh; Precup, Doina; Arnold, Douglas; Arbel, Tal

    2015-01-01

    In this paper, we present IMaGe, a new, iterative two-stage probabilistic graphical model for detection and segmentation of Multiple Sclerosis (MS) lesions. Our model includes two levels of Markov Random Fields (MRFs). At the bottom level, a regular grid voxel-based MRF identifies potential lesion voxels, as well as other tissue classes, using local and neighbourhood intensities and class priors. Contiguous voxels of a particular tissue type are grouped into regions. A higher, non-lattice MRF is then constructed, in which each node corresponds to a region, and edges are defined based on neighbourhood relationships between regions. The goal of this MRF is to evaluate the probability of candidate lesions, based on group intensity, texture and neighbouring regions. The inferred information is then propagated to the voxel-level MRF. This process of iterative inference between the two levels repeats as long as desired. The iterations suppress false positives and refine lesion boundaries. The framework is trained on 660 MRI volumes of MS patients enrolled in clinical trials from 174 different centres, and tested on a separate multi-centre clinical trial data set with 535 MRI volumes. All data consists of T1, T2, PD and FLAIR contrasts. In comparison to other MRF methods, such as, and a traditional MRF, IMaGe is much more sensitive (with slightly better PPV). It outperforms its nearest competitor by around 20% when detecting very small lesions (3-10 voxels). This is a significant result, as such lesions constitute around 40% of the total number of lesions. PMID:26221699

  8. Comparison of triple dose versus standard dose gadolinium-DTPA for detection of MRI enhancing lesions in patients with primary progressive multiple sclerosis.

    PubMed Central

    Filippi, M; Campi, A; Martinelli, V; Colombo, B; Yousry, T; Canal, N; Scotti, G; Comi, G

    1995-01-01

    This study was performed to evaluate whether a triple dose of gadolinium-DTPA (Gd-DTPA) increases the sensitivity of brain MRI for detecting enhancing lesions in patients with primary progressive multiple sclerosis (PPMS). T1 weighted brain MRI was obtained for 10 patients with PPMS in two sessions. In the first session, one scan was obtained five to seven minutes after the injection of 0.1 mmol/kg Gd-DTPA (standard dose). In the second session, six to 24 hours later, one scan before and two scans five to seven minutes and one hour after the injection of 0.3 mmol/kg Gd-DTPA (triple dose) were obtained. Four enhancing lesions were detected in two patients when the standard dose of Gd-DTPA was used. The numbers of enhancing lesions increased to 13 and the numbers of patients with such lesions to five when the triple dose of Gd-DTPA was used and to 14 and six in the one hour delayed scans. The mean contrast ratio for enhancing lesions detected with the triple dose of Gd-DTPA was higher than those for lesions present in both the standard dose (P < 0.0009) and the one hour delayed scans (P = 0.04). These data indicate that with a triple dose of Gd-DTPA many more enhancing lesions can be detected in patients with PPMS. This is important both for planning clinical trials and for detecting the presence of inflammation in vivo in the lesions of such patients. Images PMID:8530944

  9. Magnetic resonance sees lesions of multiple sclerosis

    SciTech Connect

    Ziporyn, T.

    1985-02-15

    The value of nuclear magnetic resonance imaging in the diagnosis and quantitation of the progression of multiple sclerosis is discussed. Magnetic resonance imaging generates images that reflect differential density and velocity of hydrogen nuclei between cerebral gray and white matter, as well as between white matter and pathological lesions of the disease.

  10. Improved spatial regression analysis of diffusion tensor imaging for lesion detection during longitudinal progression of multiple sclerosis in individual subjects

    NASA Astrophysics Data System (ADS)

    Liu, Bilan; Qiu, Xing; Zhu, Tong; Tian, Wei; Hu, Rui; Ekholm, Sven; Schifitto, Giovanni; Zhong, Jianhui

    2016-03-01

    Subject-specific longitudinal DTI study is vital for investigation of pathological changes of lesions and disease evolution. Spatial Regression Analysis of Diffusion tensor imaging (SPREAD) is a non-parametric permutation-based statistical framework that combines spatial regression and resampling techniques to achieve effective detection of localized longitudinal diffusion changes within the whole brain at individual level without a priori hypotheses. However, boundary blurring and dislocation limit its sensitivity, especially towards detecting lesions of irregular shapes. In the present study, we propose an improved SPREAD (dubbed improved SPREAD, or iSPREAD) method by incorporating a three-dimensional (3D) nonlinear anisotropic diffusion filtering method, which provides edge-preserving image smoothing through a nonlinear scale space approach. The statistical inference based on iSPREAD was evaluated and compared with the original SPREAD method using both simulated and in vivo human brain data. Results demonstrated that the sensitivity and accuracy of the SPREAD method has been improved substantially by adapting nonlinear anisotropic filtering. iSPREAD identifies subject-specific longitudinal changes in the brain with improved sensitivity, accuracy, and enhanced statistical power, especially when the spatial correlation is heterogeneous among neighboring image pixels in DTI.

  11. Improved spatial regression analysis of diffusion tensor imaging for lesion detection during longitudinal progression of multiple sclerosis in individual subjects.

    PubMed

    Liu, Bilan; Qiu, Xing; Zhu, Tong; Tian, Wei; Hu, Rui; Ekholm, Sven; Schifitto, Giovanni; Zhong, Jianhui

    2016-03-21

    Subject-specific longitudinal DTI study is vital for investigation of pathological changes of lesions and disease evolution. Spatial Regression Analysis of Diffusion tensor imaging (SPREAD) is a non-parametric permutation-based statistical framework that combines spatial regression and resampling techniques to achieve effective detection of localized longitudinal diffusion changes within the whole brain at individual level without a priori hypotheses. However, boundary blurring and dislocation limit its sensitivity, especially towards detecting lesions of irregular shapes. In the present study, we propose an improved SPREAD (dubbed improved SPREAD, or iSPREAD) method by incorporating a three-dimensional (3D) nonlinear anisotropic diffusion filtering method, which provides edge-preserving image smoothing through a nonlinear scale space approach. The statistical inference based on iSPREAD was evaluated and compared with the original SPREAD method using both simulated and in vivo human brain data. Results demonstrated that the sensitivity and accuracy of the SPREAD method has been improved substantially by adapting nonlinear anisotropic filtering. iSPREAD identifies subject-specific longitudinal changes in the brain with improved sensitivity, accuracy, and enhanced statistical power, especially when the spatial correlation is heterogeneous among neighboring image pixels in DTI. PMID:26948513

  12. Tumefactive Demyelinating Lesions in Multiple Sclerosis and Associated Disorders.

    PubMed

    Frederick, Meredith C; Cameron, Michelle H

    2016-03-01

    Tumefactive demyelinating lesions are rare consequences of central nervous system (CNS) idiopathic inflammatory demyelinating diseases. Tumefactive demyelinating lesions pose a diagnostic challenge because they can mimic tumors and abscesses and because they can be caused by a heterogeneous range of disorders. This article reviews the recent literature on the clinical presentation; radiographic features; prognosis; and management of tumefactive demyelinating lesions in multiple sclerosis, acute demyelinating encephalomyelitis, neuromyelitis optica, and the rare variants of multiple sclerosis including Schilder's disease, Marburg acute multiple sclerosis, and Balo's concentric sclerosis.

  13. A flexible mixed-effect negative binomial regression model for detecting unusual increases in MRI lesion counts in individual multiple sclerosis patients.

    PubMed

    Kondo, Yumi; Zhao, Yinshan; Petkau, John

    2015-06-15

    We develop a new modeling approach to enhance a recently proposed method to detect increases of contrast-enhancing lesions (CELs) on repeated magnetic resonance imaging, which have been used as an indicator for potential adverse events in multiple sclerosis clinical trials. The method signals patients with unusual increases in CEL activity by estimating the probability of observing CEL counts as large as those observed on a patient's recent scans conditional on the patient's CEL counts on previous scans. This conditional probability index (CPI), computed based on a mixed-effect negative binomial regression model, can vary substantially depending on the choice of distribution for the patient-specific random effects. Therefore, we relax this parametric assumption to model the random effects with an infinite mixture of beta distributions, using the Dirichlet process, which effectively allows any form of distribution. To our knowledge, no previous literature considers a mixed-effect regression for longitudinal count variables where the random effect is modeled with a Dirichlet process mixture. As our inference is in the Bayesian framework, we adopt a meta-analytic approach to develop an informative prior based on previous clinical trials. This is particularly helpful at the early stages of trials when less data are available. Our enhanced method is illustrated with CEL data from 10 previous multiple sclerosis clinical trials. Our simulation study shows that our procedure estimates the CPI more accurately than parametric alternatives when the patient-specific random effect distribution is misspecified and that an informative prior improves the accuracy of the CPI estimates. PMID:25784219

  14. An SPM12 extension for multiple sclerosis lesion segmentation

    NASA Astrophysics Data System (ADS)

    Roura, Eloy; Oliver, Arnau; Cabezas, Mariano; Valverde, Sergi; Pareto, Deborah; Vilanova, Joan C.; Ramió-Torrentà, Lluís.; Rovira, Àlex; Lladó, Xavier

    2016-03-01

    Purpose: Magnetic resonance imaging is nowadays the hallmark to diagnose multiple sclerosis (MS), characterized by white matter lesions. Several approaches have been recently presented to tackle the lesion segmentation problem, but none of them have been accepted as a standard tool in the daily clinical practice. In this work we present yet another tool able to automatically segment white matter lesions outperforming the current-state-of-the-art approaches. Methods: This work is an extension of Roura et al. [1], where external and platform dependent pre-processing libraries (brain extraction, noise reduction and intensity normalization) were required to achieve an optimal performance. Here we have updated and included all these required pre-processing steps into a single framework (SPM software). Therefore, there is no need of external tools to achieve the desired segmentation results. Besides, we have changed the working space from T1w to FLAIR, reducing interpolation errors produced in the registration process from FLAIR to T1w space. Finally a post-processing constraint based on shape and location has been added to reduce false positive detections. Results: The evaluation of the tool has been done on 24 MS patients. Qualitative and quantitative results are shown with both approaches in terms of lesion detection and segmentation. Conclusion: We have simplified both installation and implementation of the approach, providing a multiplatform tool1 integrated into the SPM software, which relies only on using T1w and FLAIR images. We have reduced with this new version the computation time of the previous approach while maintaining the performance.

  15. Novel lesion detection aids.

    PubMed

    Neuhaus, K W; Longbottom, C; Ellwood, R; Lussi, A

    2009-01-01

    Several non-invasive and novel aids for the detection of (and in some cases monitoring of) caries lesions have been introduced in the field of 'caries diagnostics' over the last 15 years. This chapter focusses on those available to dentists at the time of writing; continuing research is bound to lead to further developments in the coming years. Laser fluorescence is based on measurements of back-scattered fluorescence of a 655-nm light source. It enhances occlusal and (potentially) approximal lesion detection and enables semi-quantitative caries monitoring. Systematic reviews have identified false-positive results as a limitation. Quantitative light-induced fluorescence is another sensitive method to quantitatively detect and measure mineral loss both in enamel and some dentine lesions; again, the trade-offs with lower specificity when compared with clinical visual detection must be considered. Subtraction radiography is based on the principle of digitally superimposing two radiographs with exactly the same projection geometry. This method is applicable for approximal surfaces and occlusal caries involving dentine but is not yet widely available. Electrical caries measurements gather either site-specific or surface-specific information of teeth and tooth structure. Fixed-frequency devices perform best for occlusal dentine caries but the method has also shown promise for lesions in enamel and other tooth surfaces with multi-frequency approaches. All methods require further research and further validation in well-designed clinical trials. In the future, they could have useful applications in clinical practice as part of a personalized, comprehensive caries management system. PMID:19494675

  16. Role of MRI in multiple sclerosis I: inflammation and lesions.

    PubMed

    Zivadinov, Robert; Bakshi, Rohit

    2004-01-01

    Conventional magnetic resonance imaging (MRI) can improve accuracy in the diagnosis of multiple sclerosis (MS). Metrics derived from conventional MRI are now routinely used to detect therapeutic effects and extend clinical observations. Hyperintense lesions on T2-weighted MRI scans are related primarily to increased water content and thus cannot distinguish between inflammation, edema, demyelination, Wallerian degeneration, and axonal loss. In addition, T2-weighted and post-contrast images are not sufficiently sensitive to detect occult disease affecting normal appearing gray and white matter. They do not show a reliable correlation with clinical measures of disability and do not provide a complete assessment of therapeutic outcomes. In the past few years a host of advanced MRI techniques and analysis methods have been introduced for the assessment of MS. These MRI techniques appear to have better reliability as surrogate markers for monitoring the pathologic processes that most likely are related to disease activity and clinical progression. They are able to reveal a range of tissue changes that include edema, inflammation, demyelination, axonal loss, and neurodegeneration. Therefore, in a disease with a high degree of longitudinal variability of clinical signs and symptoms within and between patients, and with no current adequate biological markers of disease progression, non-conventional MRI techniques provide a powerful tool to non-invasively study pathological substrates of overt lesions and normal appearing brain tissue. In particular, the use of these techniques is promising in elucidating mechanisms underlying the accumulation of tissue damage, repair and functional reorganization of neural pathways in patients with MS.

  17. Segmentation of multiple sclerosis lesions in MRI: an image analysis approach

    NASA Astrophysics Data System (ADS)

    Krishnan, Kalpagam; Atkins, M. Stella

    1998-06-01

    This paper describes an intensity-based method for the segmentation of multiple sclerosis lesions in dual-echo PD and T2-weighted magnetic resonance brain images. The method consists of two stages: feature extraction and image analysis. For feature extraction, we use a ratio filter transformation on the proton density (PD) and spin-spin (T2) data sequences to extract the white matter, cerebrospinal fluid and the lesion features. The one and two dimensional histograms of the features are then analyzed to obtain different parameters, which provide the basis for subsequent image analysis operations to detect the multiple sclerosis lesions. In the image analysis stage, the PD images of the volume are first pre-processed to enhance the lesion tissue areas. White matter and cerebrospinal fluid masks are then generated and applied on the enhanced volume to remove non- lesion areas. Segmentation of lesions is performed in two steps: conspicuous lesions are extracted in the first step, followed by the extraction of the subtle lesions.

  18. A Model of Population and Subject (MOPS) Intensities with Application to Multiple Sclerosis Lesion Segmentation

    PubMed Central

    Tomas-Fernandez, Xavier; Warfield, Simon K.

    2015-01-01

    White matter (WM) lesions are thought to play an important role in multiple sclerosis (MS) disease burden. Recent work in the automated segmentation of white matter lesions from MRI has utilized a model in which lesions are outliers in the distribution of tissue signal intensities across the entire brain of each patient. However, the sensitivity and specificity of lesion detection and segmentation with these approaches have been inadequate. In our analysis, we determined this is due to the substantial overlap between the whole brain signal intensity distribution of lesions and normal tissue. Inspired by the ability of experts to detect lesions based on their local signal intensity characteristics, we propose a new algorithm that achieves lesion and brain tissue segmentation through simultaneous estimation of a spatially global within-the-subject intensity distribution and a spatially local intensity distribution derived from a healthy reference population. We demonstrate that MS lesions can be segmented as outliers from this intensity model of population and subject (MOPS). We carried out extensive experiments with both synthetic and clinical data, and compared the performance of our new algorithm to those of state-of-the art techniques. We found this new approach leads to a substantial improvement in the sensitivity and specificity of lesion detection and segmentation. PMID:25616008

  19. Classification of multiple sclerosis lesions using adaptive dictionary learning.

    PubMed

    Deshpande, Hrishikesh; Maurel, Pierre; Barillot, Christian

    2015-12-01

    This paper presents a sparse representation and an adaptive dictionary learning based method for automated classification of multiple sclerosis (MS) lesions in magnetic resonance (MR) images. Manual delineation of MS lesions is a time-consuming task, requiring neuroradiology experts to analyze huge volume of MR data. This, in addition to the high intra- and inter-observer variability necessitates the requirement of automated MS lesion classification methods. Among many image representation models and classification methods that can be used for such purpose, we investigate the use of sparse modeling. In the recent years, sparse representation has evolved as a tool in modeling data using a few basis elements of an over-complete dictionary and has found applications in many image processing tasks including classification. We propose a supervised classification approach by learning dictionaries specific to the lesions and individual healthy brain tissues, which include white matter (WM), gray matter (GM) and cerebrospinal fluid (CSF). The size of the dictionaries learned for each class plays a major role in data representation but it is an even more crucial element in the case of competitive classification. Our approach adapts the size of the dictionary for each class, depending on the complexity of the underlying data. The algorithm is validated using 52 multi-sequence MR images acquired from 13 MS patients. The results demonstrate the effectiveness of our approach in MS lesion classification.

  20. Classification of multiple sclerosis lesions using adaptive dictionary learning.

    PubMed

    Deshpande, Hrishikesh; Maurel, Pierre; Barillot, Christian

    2015-12-01

    This paper presents a sparse representation and an adaptive dictionary learning based method for automated classification of multiple sclerosis (MS) lesions in magnetic resonance (MR) images. Manual delineation of MS lesions is a time-consuming task, requiring neuroradiology experts to analyze huge volume of MR data. This, in addition to the high intra- and inter-observer variability necessitates the requirement of automated MS lesion classification methods. Among many image representation models and classification methods that can be used for such purpose, we investigate the use of sparse modeling. In the recent years, sparse representation has evolved as a tool in modeling data using a few basis elements of an over-complete dictionary and has found applications in many image processing tasks including classification. We propose a supervised classification approach by learning dictionaries specific to the lesions and individual healthy brain tissues, which include white matter (WM), gray matter (GM) and cerebrospinal fluid (CSF). The size of the dictionaries learned for each class plays a major role in data representation but it is an even more crucial element in the case of competitive classification. Our approach adapts the size of the dictionary for each class, depending on the complexity of the underlying data. The algorithm is validated using 52 multi-sequence MR images acquired from 13 MS patients. The results demonstrate the effectiveness of our approach in MS lesion classification. PMID:26055435

  1. Heterogeneity of Multiple Sclerosis Lesions in Multislice Myelin Water Imaging

    PubMed Central

    Faizy, Tobias Djamsched; Thaler, Christian; Kumar, Dushyant; Sedlacik, Jan; Broocks, Gabriel; Grosser, Malte; Stellmann, Jan-Patrick; Heesen, Christoph; Fiehler, Jens; Siemonsen, Susanne

    2016-01-01

    Purpose To assess neuroprotection and remyelination in Multiple Sclerosis (MS), we applied a more robust myelin water imaging (MWI) processing technique, including spatial priors into image reconstruction, which allows for lower SNR, less averages and shorter acquisition times. We sought to evaluate this technique in MS-patients and healthy controls (HC). Materials and Methods Seventeen MS-patients and 14 age-matched HCs received a 3T Magnetic Resonance Imaging (MRI) examination including MWI (8 slices, 12 minutes acquisition time), T2w and T1mprage pre and post gadolinium (GD) administration. Black holes (BH), contrast enhancing lesions (CEL) and T2 lesions were marked and registered to MWI. Additionally, regions of interest (ROI) were defined in the frontal, parietal and occipital normal appearing white matter (NAWM)/white matter (WM), the corticospinal tract (CST), the splenium (SCC) and genu (GCC) of the corpus callosum in patients and HCs. Mean values of myelin water fraction (MWF) were determined for each ROI. Results Significant differences (p≤0.05) of the MWF were found in all three different MS-lesion types (BH, CEL, T2 lesions), compared to the WM of HCs. The mean MWF values among the different lesion types were significantly differing from each other. Comparing MS-patients vs. HCs, we found a significant (p≤0.05) difference of the MWF in all measured ROIs except of GCC and SCC. The mean reduction of MWF in the NAWM of MS-patients compared to HCs was 37%. No age, sex, disability score and disease duration dependency was found for the NAWM MWF. Conclusion MWF measures were in line with previous studies and lesions were clearly visible in MWI. MWI allows for quantitative assessment of NAWM and lesions in MS, which could be used as an additional sensitive imaging endpoint for larger MS studies. Measurements of the MWF also differ between patients and healthy controls. PMID:26990645

  2. MRI phase changes in multiple sclerosis vs neuromyelitis optica lesions at 7T

    PubMed Central

    Sinnecker, Tim; Schumacher, Sophie; Mueller, Katharina; Pache, Florence; Dusek, Petr; Harms, Lutz; Ruprecht, Klemens; Nytrova, Petra; Chawla, Sanjeev; Niendorf, Thoralf; Kister, Ilya; Ge, Yulin; Wuerfel, Jens

    2016-01-01

    Objective: To characterize paramagnetic MRI phase signal abnormalities in neuromyelitis optica spectrum disorder (NMOSD) vs multiple sclerosis (MS) lesions in a cross-sectional study. Methods: Ten patients with NMOSD and 10 patients with relapsing-remitting MS underwent 7-tesla brain MRI including supratentorial T2*-weighted imaging and supratentorial susceptibility weighted imaging. Next, we analyzed intra- and perilesional paramagnetic phase changes on susceptibility weighted imaging filtered magnetic resonance phase images. Results: We frequently observed paramagnetic rim-like (75 of 232 lesions, 32%) or nodular (32 of 232 lesions, 14%) phase changes in MS lesions, but only rarely in NMOSD lesions (rim-like phase changes: 2 of 112 lesions, 2%, p < 0.001; nodular phase changes: 2 of 112 lesions, 2%, p < 0.001). Conclusions: Rim-like or nodular paramagnetic MRI phase changes are characteristic for MS lesions and not frequently detectable in NMOSD. Future prospective studies should ask whether these imaging findings can be used as a biomarker to distinguish between NMOSD- and MS-related brain lesions. PMID:27489865

  3. The development of an MRI lesion quantifying system for multiple sclerosis patients undergoing treatment

    NASA Astrophysics Data System (ADS)

    Moin, Paymann; Ma, Kevin; Amezcua, Lilyana; Gertych, Arkadiusz; Liu, Brent

    2009-02-01

    Multiple sclerosis (MS) is a demyelinating disease of the central nervous system that affects approximately 2.5 million people worldwide. Magnetic resonance imaging (MRI) is an established tool for the assessment of disease activity, progression and response to treatment. The progression of the disease is variable and requires routine follow-up imaging studies. Currently, MRI quantification of multiple sclerosis requires a manual approach to lesion measurement and yields an estimate of lesion volume and interval change. In the setting of several prior studies and a long treatment history, trends related to treatment change quickly become difficult to extrapolate. Our efforts seek to develop an imaging informatics based MS lesion computer aided detection (CAD) package to quantify and track MS lesions including lesion load, volume, and location. Together, with select clinical parameters, this data will be incorporated into an MS specific e- Folder to provide decision support to evaluate and assess treatment options for MS in a manner tailored specifically to an individual based on trends in MS presentation and progression.

  4. Automatic segmentation and volumetry of multiple sclerosis brain lesions from MR images.

    PubMed

    Jain, Saurabh; Sima, Diana M; Ribbens, Annemie; Cambron, Melissa; Maertens, Anke; Van Hecke, Wim; De Mey, Johan; Barkhof, Frederik; Steenwijk, Martijn D; Daams, Marita; Maes, Frederik; Van Huffel, Sabine; Vrenken, Hugo; Smeets, Dirk

    2015-01-01

    The location and extent of white matter lesions on magnetic resonance imaging (MRI) are important criteria for diagnosis, follow-up and prognosis of multiple sclerosis (MS). Clinical trials have shown that quantitative values, such as lesion volumes, are meaningful in MS prognosis. Manual lesion delineation for the segmentation of lesions is, however, time-consuming and suffers from observer variability. In this paper, we propose MSmetrix, an accurate and reliable automatic method for lesion segmentation based on MRI, independent of scanner or acquisition protocol and without requiring any training data. In MSmetrix, 3D T1-weighted and FLAIR MR images are used in a probabilistic model to detect white matter (WM) lesions as an outlier to normal brain while segmenting the brain tissue into grey matter, WM and cerebrospinal fluid. The actual lesion segmentation is performed based on prior knowledge about the location (within WM) and the appearance (hyperintense on FLAIR) of lesions. The accuracy of MSmetrix is evaluated by comparing its output with expert reference segmentations of 20 MRI datasets of MS patients. Spatial overlap (Dice) between the MSmetrix and the expert lesion segmentation is 0.67 ± 0.11. The intraclass correlation coefficient (ICC) equals 0.8 indicating a good volumetric agreement between the MSmetrix and expert labelling. The reproducibility of MSmetrix' lesion volumes is evaluated based on 10 MS patients, scanned twice with a short interval on three different scanners. The agreement between the first and the second scan on each scanner is evaluated through the spatial overlap and absolute lesion volume difference between them. The spatial overlap was 0.69 ± 0.14 and absolute total lesion volume difference between the two scans was 0.54 ± 0.58 ml. Finally, the accuracy and reproducibility of MSmetrix compare favourably with other publicly available MS lesion segmentation algorithms, applied on the same data using default parameter

  5. Segmentation of multiple sclerosis lesions using support vector machines

    NASA Astrophysics Data System (ADS)

    Ferrari, Ricardo J.; Wei, Xingchang; Zhang, Yunyan; Scott, James N.; Mitchell, J. R.

    2003-05-01

    In this paper we present preliminary results to automatically segment multiple sclerosis (MS) lesions in multispectral magnetic resonance datasets using support vector machines (SVM). A total of eighteen studies (each composed of T1-, T2-weighted and FLAIR images) acquired from a 3T GE Signa scanner was analyzed. A neuroradiologist used a computer-assisted technique to identify all MS lesions in each study. These results were used later in the training and testing stages of the SVM classifier. A preprocessing stage including anisotropic diffusion filtering, non-uniformity intensity correction, and intensity tissue normalization was applied to the images. The SVM kernel used in this study was the radial basis function (RBF). The kernel parameter (γ) and the penalty value for the errors were determined by using a very loose stopping criterion for the SVM decomposition. Overall, a 5-fold cross-validation accuracy rate of 80% was achieved in the automatic classification of MS lesion voxels using the proposed SVM-RBF classifier.

  6. Pathological differences between white and grey matter multiple sclerosis lesions.

    PubMed

    Prins, Marloes; Schul, Emma; Geurts, Jeroen; van der Valk, Paul; Drukarch, Benjamin; van Dam, Anne-Marie

    2015-09-01

    Multiple sclerosis (MS) is a debilitating disease characterized by demyelination of the central nervous system (CNS), resulting in widespread formation of white matter lesions (WMLs) and grey matter lesions (GMLs). WMLs are pathologically characterized by the presence of immune cells that infiltrate the CNS, whereas these immune cells are barely present in GMLs. This striking pathological difference between WMLs and GMLs raises questions about the underlying mechanism. It is known that infiltrating leukocytes contribute to the generation of WMLs; however, since GMLs show a paucity of infiltrating immune cells, their importance in GML formation remains to be determined. Here, we review pathological characteristics of WMLs and GMLs, and suggest some possible explanations for the observed pathological differences. In our view, cellular and molecular characteristics of WM and GM, and local differences within WMLs and GMLs (in particular, in glial cell populations and the molecules they express), determine the pathway to demyelination. Further understanding of GML pathogenesis, considered to contribute to chronic MS, may have a direct impact on the development of novel therapeutic targets to counteract this progressive neurological disorder.

  7. DIR-visible grey matter lesions and atrophy in multiple sclerosis: partners in crime?

    PubMed Central

    van de Pavert, Steven H P; Muhlert, Nils; Sethi, Varun; Wheeler-Kingshott, Claudia A M; Geurts, Jeroen J G; Ron, Maria; Yousry, Tarek A; Thompson, Alan J; Miller, David H; Chard, Declan T; Ciccarelli, Olga

    2016-01-01

    Background The extent and clinical relevance of grey matter (GM) pathology in multiple sclerosis (MS) are increasingly recognised. GM pathology may present as focal lesions, which can be visualised using double inversion recovery (DIR) MRI, or as diffuse pathology, which can manifest as atrophy. It is, however, unclear whether the diffuse atrophy centres on focal lesions. This study aimed to determine if GM lesions and GM atrophy colocalise, and to assess their independent relationship with motor and cognitive deficits in MS. Methods Eighty people with MS and 30 healthy controls underwent brain volumetric T1-weighted and DIR MRI at 3 T, and had a comprehensive neurological and cognitive assessment. Probability mapping of GM lesions marked on the DIR scans and voxel- based morphometry (assessing GM atrophy) were carried out. The associations of GM lesion load and GM volume with clinical scores were tested. Results DIR-visible GM lesions were most commonly found in the right cerebellum and most apparent in patients with primary progressive MS. Deep GM structures appeared largely free from lesions, but showed considerable atrophy, particularly in the thalamus, caudate, pallidum and putamen, and this was most apparent in secondary progressive patients with MS. Very little co-localisation of GM atrophy and lesions was seen, and this was generally confined to the cerebellum and postcentral gyrus. In both regions, GM lesions and volume independently correlated with physical disability and cognitive performance. Conclusions DIR-detectable GM lesions and GM atrophy do not significantly overlap in the brain but, when they do, they independently contribute to clinical disability. PMID:25926483

  8. Knowledge guided information fusion for segmentation of multiple sclerosis lesions in MRI images

    NASA Astrophysics Data System (ADS)

    Zhu, Chaozhe; Jiang, Tianzi

    2003-05-01

    In this work, T1-, T2- and PD-weighted MR images of multiple sclerosis (MS) patients, providing information on the properties of tissues from different aspects, are treated as three independent information sources for the detection and segmentation of MS lesions. Based on information fusion theory, a knowledge guided information fusion framework is proposed to accomplish 3-D segmentation of MS lesions. This framework consists of three parts: (1) information extraction, (2) information fusion, and (3) decision. Information provided by different spectral images is extracted and modeled separately in each spectrum using fuzzy sets, aiming at managing the uncertainty and ambiguity in the images due to noise and partial volume effect. In the second part, the possible fuzzy map of MS lesions in each spectral image is constructed from the extracted information under the guidance of experts' knowledge, and then the final fuzzy map of MS lesions is constructed through the fusion of the fuzzy maps obtained from different spectrum. Finally, 3-D segmentation of MS lesions is derived from the final fuzzy map. Experimental results show that this method is fast and accurate.

  9. Small white matter lesion detection in cerebral small vessel disease

    NASA Astrophysics Data System (ADS)

    Ghafoorian, Mohsen; Karssemeijer, Nico; van Uden, Inge; de Leeuw, Frank E.; Heskes, Tom; Marchiori, Elena; Platel, Bram

    2015-03-01

    Cerebral small vessel disease (SVD) is a common finding on magnetic resonance images of elderly people. White matter lesions (WML) are important markers for not only the small vessel disease, but also neuro-degenerative diseases including multiple sclerosis, Alzheimer's disease and vascular dementia. Volumetric measurements such as the "total lesion load", have been studied and related to these diseases. With respect to SVD we conjecture that small lesions are important, as they have been observed to grow over time and they form the majority of lesions in number. To study these small lesions they need to be annotated, which is a complex and time-consuming task. Existing (semi) automatic methods have been aimed at volumetric measurements and large lesions, and are not suitable for the detection of small lesions. In this research we established a supervised voxel classification CAD system, optimized and trained to exclusively detect small WMLs. To achieve this, several preprocessing steps were taken, which included a robust standardization of subject intensities to reduce inter-subject intensity variability as much as possible. A number of features that were found to be well identifying small lesions were calculated including multimodal intensities, tissue probabilities, several features for accurate location description, a number of second order derivative features as well as multi-scale annular filter for blobness detection. Only small lesions were used to learn the target concept via Adaboost using random forests as its basic classifiers. Finally the results were evaluated using Free-response receiver operating characteristic.

  10. Model-based 3-D segmentation of multiple sclerosis lesions in dual-echo MRI data

    NASA Astrophysics Data System (ADS)

    Kamber, Micheline; Collins, D. Louis; Shinghal, Rajjan; Francis, G. S.; Evans, Alan C.

    1992-09-01

    This paper describes the development and use of a brain tissue probability model for the segmentation of multiple sclerosis lesions in magnetic resonance (MR) images of the human brain. Based on MR data obtained from a group of healthy volunteers, the model was constructed to provide prior probabilities of grey matter, white matter, ventricular cerebrospinal fluid (CSF), and external CSF distribution per unit voxel in a standardized 3- dimensional `brain space.' In comparison to purely data-driven segmentation, the use of the model to guide the segmentation of multiple sclerosis lesions reduced the volume of false positive lesions by 50%.

  11. Measuring the lesion load of multiple sclerosis patients within the corticospinal tract

    NASA Astrophysics Data System (ADS)

    Klein, Jan; Hanken, Katrin; Koceva, Jasna; Hildebrandt, Helmut; Hahn, Horst K.

    2015-03-01

    In this paper we present a framework for reliable determination of the lesion load within the corticospinal tract (CST) of multiple sclerosis patients. The basis constitutes a probabilistic fiber tracking approach which checks possible parameter intervals on the fly using an anatomical brain atlas. By exploiting the range of those intervals, the algorithm is able to resolve fiber crossings and to determine the CST in its full entity although it can use a simple diffusion tensor model. Another advantage is its short running time, tracking the CST takes less than a minute. For segmenting the lesions we developed a semi-automatic approach. First, a trained classifier is applied to multimodal MRI data (T1/FLAIR) where the spectrum of lesions has been determined in advance by a clustering algorithm. This leads to an automatic detection of the lesions which can be manually corrected afterwards using a threshold-based approach. For evaluation we scanned 46 MS patients and 16 healthy controls. Fiber tracking has been performed using our novel fiber tracking and a standard defection based algorithm. Regression analysis of the old and new version of the algorithm showed a highly significant superiority of the new algorithm for disease duration. Additionally, a low correlation between old and new approach supports the observation that standard DTI fiber tracking is not always able to track and quantify the CST reliably.

  12. Chemical analysis of multiple sclerosis lesions by FT-IR microspectroscopy

    NASA Astrophysics Data System (ADS)

    Levine, Steven M.; Wetzel, David L.

    1998-06-01

    Fourier transform infrared microspectroscopy can be used to collect infrared spectra from microscopic regions of tissue sections. If spectra are collected along a grid pattern, then maps of chemical functional groups can be produced and correlated to tissue histopathology. In the present study, white matter from multiple sclerosis and control brains were examined. Mapping experiments were designed such that 17 spectra were collected at 200 μm intervals along a line that was partially or wholly within a multiple sclerosis lesion site or within a representative white matter region of control tissue. Data analysis was based on earlier in vitro studies, which found that the carbonyl at 1740 cm-1 increases when lipids become oxidized, and the amide I peak at ~1660 cm-1 broadens when proteins become oxidized. The results indicated that the C=O to CH2 ratio (1740 cm-1:1468 cm-1) was elevated at several collection points in lesion sites from each of five multiple sclerosis brains examined compared to values from white matter of four control brains. Inspection of the amide I peak at 1657 cm-1 revealed that it was broadened towards 1652 cm-1 in multiple sclerosis tissues but not control tissues. These results suggest that lipids and proteins are oxidized at active multiple sclerosis lesion sites. The localization of these products to lesion sites supports a role for free radicals in the pathogenesis of multiple sclerosis.

  13. High field (9.4 Tesla) magnetic resonance imaging of cortical grey matter lesions in multiple sclerosis.

    PubMed

    Schmierer, Klaus; Parkes, Harold G; So, Po-Wah; An, Shu F; Brandner, Sebastian; Ordidge, Roger J; Yousry, Tarek A; Miller, David H

    2010-03-01

    Multiple sclerosis is an inflammatory, degenerative disease of the central nervous system. The most obvious pathological change in multiple sclerosis is multifocal demyelination of the white matter, but grey matter demyelination may be of equal or even greater importance for its clinical manifestations. In order to assess the pathogenetic role of lesions in the grey and white matter, and to explore the association between demyelinated and non-lesional brain tissue, tools are needed to depict each of these tissue components accurately in vivo. Due to its sensitivity in detecting white matter lesions, T(2)-weighted magnetic resonance imaging at 1.5 T is important in the diagnosis of multiple sclerosis. However, magnetic resonance imaging at 1.5 T largely fails to detect grey matter lesions. In this study, we used T(2)-weighted magnetic resonance imaging at 9.4 T to detect grey matter lesions in fixed post-mortem multiple sclerosis motor cortex. Furthermore, we produced T(1), T(2) and magnetization transfer ratio maps, and correlated these indices with quantitative histology [neuronal density, intensity of immunostaining for myelin basic protein (reflecting myelin content) and phosphorylated neurofilament (reflecting axonal area)] using t-tests and multivariate regression. In 21 tissue samples, 28 cortical grey matter lesions were visible on both T(2)-weighted magnetic resonance imaging and sections immunostained for myelin basic protein, 15/28 being mixed white and grey matter and 11/28 subpial cortical grey matter lesions; 2/28 cortical grey matter lesions involved all layers of the cortex. Compared with non-lesional cortex, cortical grey matter lesions showed reduction of neuronal density (98/mm(2), SD = 34/mm(2;) versus 129/mm(2), SD = 44; P < 0.01), phosphorylated neurofilament (1/transmittance = 1.16; SD = 0.09 versus 1.24; SD = 0.1; P < 0.01) and magnetization transfer ratio (31.1 pu; SD = 11.9 versus 37.5 pu; SD = 8.7; P = 0.01), and an increase of T(2) (25

  14. A genome-wide association study of brain lesion distribution in multiple sclerosis.

    PubMed

    Gourraud, Pierre-Antoine; Sdika, Michael; Khankhanian, Pouya; Henry, Roland G; Beheshtian, Azadeh; Matthews, Paul M; Hauser, Stephen L; Oksenberg, Jorge R; Pelletier, Daniel; Baranzini, Sergio E

    2013-04-01

    Brain magnetic resonance imaging is widely used as a diagnostic and monitoring tool in multiple sclerosis and provides a non-invasive, sensitive and reproducible way to track the disease. Topological characteristics relating to the distribution and shape of lesions are recognized as important neuroradiological markers in the diagnosis of multiple sclerosis, although these have been much less well characterized quantitatively than have traditional measures such as T2 hyperintense or T1 hypointense lesion volumes. Here, we used voxel-level 3 T magnetic resonance imaging T1-weighted scans to reconstruct the 3D topology of lesions in 284 subjects with multiple sclerosis and tested whether this is a heritable phenotype. To this end, we extracted the genotypes from a published genome-wide association study on these same individuals and searched for genetic associations with lesion load, shape and topological distribution. Lesion probability maps were created to identify frequently affected areas and to assess the overall distribution of T1 lesions in the subject population as a whole. We then developed an original algorithm to cluster adjacent lesional voxels (cluxels) in each subject and tested whether cluxel topology was significantly associated with any single-nucleotide polymorphism in our data set. To focus on patterns of lesion distribution, we computed the first 10 principal components. Although principal component 1 correlated with lesion load, none of the remaining orthogonal components correlated with any other known variable. We then conducted genome-wide association studies on each of these and found 31 significant associations (false discovery rate <0.01) with principal component 8, which represents a mode of variation of lesion topology in the population. The majority of the loci can be linked to genes related to immune cell function and to myelin and neural growth; some (SYK, MYT1L, TRAPPC9, SLITKR6 and RIC3) have been previously associated with the

  15. BG-12 reduces evolution of new enhancing lesions to T1-hypointense lesions in patients with multiple sclerosis.

    PubMed

    MacManus, D G; Miller, D H; Kappos, L; Gold, R; Havrdova, E; Limmroth, V; Polman, C H; Schmierer, K; Yousry, T A; Eraksoy, M; Meluzinova, E; Dufek, M; Yang, M; O'Neill, G N; Dawson, K

    2011-03-01

    BG-12, an immunomodulatory agent, reduces frequency of new gadolinium-enhancing (Gd+) lesions in relapsing multiple sclerosis (MS). This study reports the effect of 240 mg BG-12 orally three times daily (tid) for 24 weeks on the evolution of new Gd+ lesions to T1-hypointense lesions. Brain magnetic resonance imaging (MRI) scans from patients in placebo and 240 mg BG-12 tid arms of a phase 2b study were examined retrospectively. Included patients had at least one new Gd+ lesion from weeks 4 to 12. Week 24 scans were analyzed for number and proportion of new Gd+ lesions that evolved to T1-hypointense lesions. Eighteen patients receiving BG-12 and 38 patients receiving placebo were included in the analysis. The analysis tracked 147 new Gd+ lesions in patients from the BG-12 group and 221 Gd+ lesions in patients from the placebo group. The percentage of Gd+ lesions that evolved to T1-hypointense lesions was 34% lower with BG-12 treatment versus placebo (29%, BG-12; 44%, placebo; odds ratio 0.51; 95% confidence interval 0.43, 0.61; p < 0.0001). In addition to reducing frequency of new Gd+ lesions, BG-12 significantly reduced probability of their evolution to T1-hypointense lesions in patients with MS compared with placebo.

  16. Imaging inflammatory acne: lesion detection and tracking

    NASA Astrophysics Data System (ADS)

    Cula, Gabriela O.; Bargo, Paulo R.; Kollias, Nikiforos

    2010-02-01

    It is known that effectiveness of acne treatment increases when the lesions are detected earlier, before they could progress into mature wound-like lesions, which lead to scarring and discoloration. However, little is known about the evolution of acne from early signs until after the lesion heals. In this work we computationally characterize the evolution of inflammatory acne lesions, based on analyzing cross-polarized images that document acne-prone facial skin over time. Taking skin images over time, and being able to follow skin features in these images present serious challenges, due to change in the appearance of skin, difficulty in repositioning the subject, involuntary movement such as breathing. A computational technique for automatic detection of lesions by separating the background normal skin from the acne lesions, based on fitting Gaussian distributions to the intensity histograms, is presented. In order to track and quantify the evolution of lesions, in terms of the degree of progress or regress, we designed a study to capture facial skin images from an acne-prone young individual, followed over the course of 3 different time points. Based on the behavior of the lesions between two consecutive time points, the automatically detected lesions are classified in four categories: new lesions, resolved lesions (i.e. lesions that disappear completely), lesions that are progressing, and lesions that are regressing (i.e. lesions in the process of healing). The classification our methods achieve correlates well with visual inspection of a trained human grader.

  17. Occurrence and long-term outcome of tumefactive demyelinating lesions in multiple sclerosis.

    PubMed

    Totaro, Rocco; Di Carmine, C; Splendiani, A; Torlone, S; Patriarca, L; Carrocci, C; Sciamanna, S; Marini, C; Carolei, A

    2016-07-01

    Although tumefactive multiple sclerosis is a well recognized variant of multiple sclerosis, prognostic uncertainty still exists about long term prognosis. The aim of this study was to estimate the occurrence and long term outcome of tumefactive demyelinating lesions (TDLs) in a cohort of multiple sclerosis patients. We reviewed brain MRI of 443 patients referred to our MS clinic. All patients meeting the McDonald criteria for multiple sclerosis and showing at least one TDL were included. Kaplan-Meier estimates of disease-free survival in patient cohort were compared with control group without TDLs using a log-rank test. Seven cases with TDLs were identified (occurrence 1.58 %). Tumefactive demyelinating lesion recurrence was 16.6 %. Cumulative proportion of patients free from clinical relapse and from new T2 lesions was lower in the control group although not reaching statistical significance (30 vs 50 %; P = 0.666 and 21.7 vs 33.3 %; P = 0.761, respectively). Disability progression analysis showed a not significant trend towards lower probability of remaining progression free for TDL patients (50 vs 61 %; P = 0.295). Occurrence of tumefactive demyelinating lesions in our cohort was higher than those reported in other studies. Overall, TDLs were not predictive of poor outcome in terms of disability progression.

  18. Cause and prevention of demyelination in a model multiple sclerosis lesion

    PubMed Central

    Davies, Andrew L.; Tachrount, Mohamed; Kasti, Marianne; Laulund, Frida; Golay, Xavier; Smith, Kenneth J.

    2016-01-01

    Objective Demyelination is a cardinal feature of multiple sclerosis, but it remains unclear why new lesions form, and whether they can be prevented. Neuropathological evidence suggests that demyelination can occur in the relative absence of lymphocytes, and with distinctive characteristics suggestive of a tissue energy deficit. The objective was to examine an experimental model of the early multiple sclerosis lesion and identify pathogenic mechanisms and opportunities for therapy. Methods Demyelinating lesions were induced in the rat spinal dorsal column by microinjection of lipopolysaccharide, and examined immunohistochemically at different stages of development. The efficacy of treatment with inspired oxygen for 2 days following lesion induction was evaluated. Results Demyelinating lesions were not centered on the injection site, but rather formed 1 week later at the white–gray matter border, preferentially including the ventral dorsal column watershed. Lesion formation was preceded by a transient early period of hypoxia and increased production of superoxide and nitric oxide. Oligodendrocyte numbers decreased at the site shortly afterward, prior to demyelination. Lesions formed at a site of inherent susceptibility to hypoxia, as revealed by exposure of naive animals to a hypoxic environment. Notably, raising the inspired oxygen (80%, normobaric) during the hypoxic period significantly reduced or prevented the demyelination. Interpretation Demyelination characteristic of at least some early multiple sclerosis lesions can arise at a vascular watershed following activation of innate immune mechanisms that provoke hypoxia, and superoxide and nitric oxide formation, all of which can compromise cellular energy sufficiency. Demyelination can be reduced or eliminated by increasing inspired oxygen to alleviate the transient hypoxia. Ann Neurol 2016;79:591–604 PMID:26814844

  19. Detection and quantification of MS lesions using fuzzy topological principles

    NASA Astrophysics Data System (ADS)

    Udupa, Jayaram K.; Wei, Luogang; Samarasekera, Supun; Miki, Yukio; van Buchem, M. A.; Grossman, Robert I.

    1996-04-01

    Quantification of the severity of the multiple sclerosis (MS) disease through estimation of lesion volume via MR imaging is vital for understanding and monitoring the disease and its treatment. This paper presents a novel methodology and a system that can be routinely used for segmenting and estimating the volume of MS lesions via dual-echo spin-echo MR imagery. An operator indicates a few points in the images by pointing to the white matter, the gray matter, and the CSF. Each of these objects is then detected as a fuzzy connected set. The holes in the union of these objects correspond to potential lesion sites which are utilized to detect each potential lesion as a fuzzy connected object. These 3D objects are presented to the operator who indicates acceptance/rejection through the click of a mouse button. The volume of accepted lesions is then computed and output. Based on several evaluation studies and over 300 3D data sets that were processed, we conclude that the methodology is highly reliable and consistent, with a coefficient of variation (due to subjective operator actions) of less than 1.0% for volume.

  20. Morphogenesis of the demyelinating lesions in Baló's concentric sclerosis.

    PubMed

    Barz, Helmut; Barz, Ulrich; Schreiber, Almut

    2016-06-01

    lesions in Baló's concentric sclerosis and multiple sclerosis. PMID:27142145

  1. Activation status of human microglia is dependent on lesion formation stage and remyelination in multiple sclerosis.

    PubMed

    Peferoen, Laura A N; Vogel, Daphne Y S; Ummenthum, Kimberley; Breur, Marjolein; Heijnen, Priscilla D A M; Gerritsen, Wouter H; Peferoen-Baert, Regina M B; van der Valk, Paul; Dijkstra, Christine D; Amor, Sandra

    2015-01-01

    Similar to macrophages, microglia adopt diverse activation states and contribute to repair and tissue damage in multiple sclerosis. Using reverse transcription-quantitative polymerase chain reaction and immunohistochemistry, we show that in vitro M1-polarized (proinflammatory) human adult microglia express the distinctive markers CD74, CD40, CD86, and CCR7, whereas M2 (anti-inflammatory) microglia express mannose receptor and the anti-inflammatory cytokine CCL22. The expression of these markers was assessed in clusters of activated microglia in normal-appearing white matter (preactive lesions) and areas of remyelination, representing reparative multiple sclerosis lesions. We show that activated microglia in preactive and remyelinating lesions express CD74, CD40, CD86, and the M2 markers CCL22 and CD209, but not mannose receptor. To examine whether this intermediate microglia profile is static or dynamic and thus susceptible to changes in the microenvironment, we polarized microglia into M1 or M2 phenotype in vitro and then subsequently treated them with the opposing polarization regimen. These studies revealed that expression of CD40, CXCL10, and mannose receptor is dynamic and that microglia, like macrophages, can switch between M1 and M2 phenotypic profiles. Taken together, our data define the differential activation states of microglia during lesion development in multiple sclerosis-affected CNS tissues and underscore the plasticity of human adult microglia in vitro.

  2. Multi-output decision trees for lesion segmentation in multiple sclerosis

    NASA Astrophysics Data System (ADS)

    Jog, Amod; Carass, Aaron; Pham, Dzung L.; Prince, Jerry L.

    2015-03-01

    Multiple Sclerosis (MS) is a disease of the central nervous system in which the protective myelin sheath of the neurons is damaged. MS leads to the formation of lesions, predominantly in the white matter of the brain and the spinal cord. The number and volume of lesions visible in magnetic resonance (MR) imaging (MRI) are important criteria for diagnosing and tracking the progression of MS. Locating and delineating lesions manually requires the tedious and expensive efforts of highly trained raters. In this paper, we propose an automated algorithm to segment lesions in MR images using multi-output decision trees. We evaluated our algorithm on the publicly available MICCAI 2008 MS Lesion Segmentation Challenge training dataset of 20 subjects, and showed improved results in comparison to state-of-the-art methods. We also evaluated our algorithm on an in-house dataset of 49 subjects with a true positive rate of 0.41 and a positive predictive value 0.36.

  3. Multi-Output Decision Trees for Lesion Segmentation in Multiple Sclerosis

    PubMed Central

    Jog, Amod; Carass, Aaron; Pham, Dzung L.; Prince, Jerry L.

    2016-01-01

    Multiple Sclerosis (MS) is a disease of the central nervous system in which the protective myelin sheath of the neurons is damaged. MS leads to the formation of lesions, predominantly in the white matter of the brain and the spinal cord. The number and volume of lesions visible in magnetic resonance (MR) imaging (MRI) are important criteria for diagnosing and tracking the progression of MS. Locating and delineating lesions manually requires the tedious and expensive efforts of highly trained raters. In this paper, we propose an automated algorithm to segment lesions in MR images using multi-output decision trees. We evaluated our algorithm on the publicly available MICCAI 2008 MS Lesion Segmentation Challenge training dataset of 20 subjects, and showed improved results in comparison to state-of-the-art methods. We also evaluated our algorithm on an in-house dataset of 49 subjects with a true positive rate of 0.41 and a positive predictive value 0.36.

  4. Evaluation of an automatic multiple sclerosis lesion quantification tool in an informatics-based MS e-folder system

    NASA Astrophysics Data System (ADS)

    Ma, Kevin; Fernandez, James; Amezcua, Lilyana; Lerner, Alex; Liu, Brent

    2011-03-01

    Multiple sclerosis (MS) is a demyelinating disease of the central nervous system. The chronic nature of MS necessitates multiple MRI studies to track disease progression. We have presented an imaging informatics decision-support system, called MS eFolder, designed to integrate patient clinical data with MR images and a computer-aided detection (CAD) component for automatic white matter lesion quantification. The purpose of the MS eFolder is to comprehensively present MS patient data for clinicians and radiologists, while providing a lesion quantification tool that can be objective and consistent for MS tracking in longitudinal studies. The MS CAD algorithm is based on the K-nearest neighbor (KNN) principles and has been integrated within the eFolder system. Currently, the system has been completed and the CAD algorithm for quantifying MS lesions has undergone the expert evaluation in order to validate system performance and accuracy. The evaluation methodology has been developed and the data has been collected, including over 100 MS MRI cases with various age and ethnic backgrounds. The preliminary results of the evaluation are expected to include sensitivity and specificity of lesion and non-lesion voxels in the white matter, the effectiveness of different probability thresholds for each voxel, and comparison between CAD quantification results and radiologists' manual readings. The results aim to show the effectiveness of a MS lesion CAD system to be used in a clinical setting, as well as a step closer to full clinical implementation of the eFolder system.

  5. Performance evaluation for volumetric segmentation of multiple sclerosis lesions using MATLAB and computing engine in the graphical processing unit (GPU)

    NASA Astrophysics Data System (ADS)

    Le, Anh H.; Park, Young W.; Ma, Kevin; Jacobs, Colin; Liu, Brent J.

    2010-03-01

    Multiple Sclerosis (MS) is a progressive neurological disease affecting myelin pathways in the brain. Multiple lesions in the white matter can cause paralysis and severe motor disabilities of the affected patient. To solve the issue of inconsistency and user-dependency in manual lesion measurement of MRI, we have proposed a 3-D automated lesion quantification algorithm to enable objective and efficient lesion volume tracking. The computer-aided detection (CAD) of MS, written in MATLAB, utilizes K-Nearest Neighbors (KNN) method to compute the probability of lesions on a per-voxel basis. Despite the highly optimized algorithm of imaging processing that is used in CAD development, MS CAD integration and evaluation in clinical workflow is technically challenging due to the requirement of high computation rates and memory bandwidth in the recursive nature of the algorithm. In this paper, we present the development and evaluation of using a computing engine in the graphical processing unit (GPU) with MATLAB for segmentation of MS lesions. The paper investigates the utilization of a high-end GPU for parallel computing of KNN in the MATLAB environment to improve algorithm performance. The integration is accomplished using NVIDIA's CUDA developmental toolkit for MATLAB. The results of this study will validate the practicality and effectiveness of the prototype MS CAD in a clinical setting. The GPU method may allow MS CAD to rapidly integrate in an electronic patient record or any disease-centric health care system.

  6. Smoking is associated with increased lesion volumes and brain atrophy in multiple sclerosis

    PubMed Central

    Zivadinov, R; Weinstock-Guttman, B; Hashmi, K; Abdelrahman, N; Stosic, M; Dwyer, M; Hussein, S; Durfee, J; Ramanathan, M

    2009-01-01

    Background: Cigarette smoking has been linked to higher susceptibility and increased risk of progressive multiple sclerosis (MS). The effects of smoking on MRI characteristics of patients with MS have not been evaluated. Objectives: To compare the MRI characteristics in cigarette smoker and nonsmoker patients with MS. Methods: We studied 368 consecutive patients with MS (age 44.0 ±SD 10.2 years, disease duration 12.1 ± 9.1 years) comprising 240 never-smokers and 128 (34.8%) ever-smokers (currently active and former smokers). The average number of packs per day smoked (±SD) was 0.95 ± 0.65, and the mean duration of smoking was 18.0 ± 9.5 years. All patients obtained full clinical and quantitative MRI evaluation. MRI measures included T1, T2, and gadolinium contrast-enhancing (CE) lesion volumes (LVs) and measures of central, global, and tissue-specific brain atrophy. The associations between smoking status and MRI measurements were assessed in regression analysis. Results: Smoking was associated with increased Expanded Disability Status Scale (EDSS) scores (p = 0.004). The median EDSS scores (interquartile range) in the ever-smoker group and the active-smoker group were both 3.0 (2.0), compared with 2.5 (2.5) in never-smokers. There were adverse associations between smoking and the lesion measures including increased number of CE lesions (p < 0.001), T2 LV (p = 0.009), and T1 LV (p = 0.003). Smoking was associated with decreased brain parenchymal fraction (p = 0.047) and with increases in the lateral ventricle volume (p = 0.001) and third ventricle width (p = 0.023). Conclusions: Smoking is associated with increased blood–brain barrier disruption, higher lesion volumes, and greater atrophy in multiple sclerosis. GLOSSARY BPF = brain parenchymal fraction; CE = contrast-enhancing; CIS = clinically isolated syndromes; EDSS = Expanded Disability Status Scale; GMF = gray matter fraction; LV = lesion volume; LVV = lateral ventricle volume; MS = multiple sclerosis

  7. Detection of Fundus Lesions Using Classifier Selection

    NASA Astrophysics Data System (ADS)

    Nagayoshi, Hiroto; Hiramatsu, Yoshitaka; Sako, Hiroshi; Himaga, Mitsutoshi; Kato, Satoshi

    A system for detecting fundus lesions caused by diabetic retinopathy from fundus images is being developed. The system can screen the images in advance in order to reduce the inspection workload on doctors. One of the difficulties that must be addressed in completing this system is how to remove false positives (which tend to arise near blood vessels) without decreasing the detection rate of lesions in other areas. To overcome this difficulty, we developed classifier selection according to the position of a candidate lesion, and we introduced new features that can distinguish true lesions from false positives. A system incorporating classifier selection and these new features was tested in experiments using 55 fundus images with some lesions and 223 images without lesions. The results of the experiments confirm the effectiveness of the proposed system, namely, degrees of sensitivity and specificity of 98% and 81%, respectively.

  8. Lesion comparison of multiple sclerosis in hispanic and caucasian patients utilizing an imaging informatics-based eFolder system

    NASA Astrophysics Data System (ADS)

    Ma, Kevin; Fernandez, James; Amezcua, Lilyana; Lerner, Alex; Shiroishi, Mark; Liu, Brent

    2012-02-01

    Multiple sclerosis (MS) is a demyelinating disease in the central nervous system. Genetics have been considered as a leading factor in the prevalence and disease course of MS. We have presented an informatics-based eFolder system for integrating patients' clinical data with MR images and lesion quantification results. The completed eFolder system has been designed and developed in aiding to evaluate disease manifestation differences in Hispanic and Caucasian MS patients. MS lesion data, as shown in MRI, can be extracted by the 3-D automatic lesion detection tool in the eFolder, and data storing and mining tools in eFolder is able to extract and compare data from individual patients. The computer-aided detection (CAD) algorithm has been modified and enhanced to include spatial information as detection criteria. For this study, 36 Caucasian MS patients and 36 matched Hispanic patients have been selected. Most recent MR images of the patients are collected, and images are evaluated both by the CAD tool in the eFolder and radiologists. The results are compared between Caucasian and Hispanic patients and statistically evaluated to see if the two populations have significant difference in lesion presentations. The results can be used to evaluate differences in the two groups of patients and to evaluate the new CAD algorithm's performance with radiologists' contours. Significant findings can further evaluate effectiveness of MS eFolder in MS-related research.

  9. Atypical idiopathic inflammatory demyelinating lesions: prognostic implications and relation to multiple sclerosis.

    PubMed

    Wallner-Blazek, Mirja; Rovira, Alex; Fillipp, Massimo; Rocca, Mara A; Miller, David H; Schmierer, Klaus; Frederiksen, Jette; Gass, Achim; Gama, Hugo; Tilbery, Charles P; Rocha, Antonio J; Flores, José; Barkhof, Frederik; Seewann, Alexandra; Palace, Jacqueline; Yousry, Tarek; Montalban, Xavier; Enzinger, Christian; Fazekas, Franz

    2013-08-01

    Atypical lesions of a presumably idiopathic inflammatory demyelinating origin present quite variably and may pose diagnostic problems. The subsequent clinical course is also uncertain. We, therefore, wanted to clarify if atypical idiopathic inflammatory demyelinating lesions (AIIDLs) can be classified according to previously suggested radiologic characteristics and how this classification relates to prognosis. Searching the databases of eight tertiary referral centres we identified 90 adult patients (61 women, 29 men; mean age 34 years) with ≥ 1 AIIDL. We collected their demographic, clinical and magnetic resonance imaging data and obtained follow-up (FU) information on 77 of these patients over a mean duration of 4 years. The AIIDLs presented as a single lesion in 72 (80 %) patients and exhibited an infiltrative (n = 35), megacystic (n = 16), Baló (n = 10) or ring-like (n = 16) lesion appearance in 77 (86 %) patients. Additional multiple sclerosis (MS)-typical lesions existed in 48 (53 %) patients. During FU, a further clinical attack occurred rarely (23-35 % of patients) except for patients with ring-like AIIDLs (62 %). Further attacks were also significantly more often in patients with coexisting MS-typical lesions (41 vs. 10 %, p < 0.005). New AIIDLs developed in six (7 %), and new MS-typical lesions in 29 (42 %) patients. Our findings confirm the previously reported subtypes of AIIDLs. Most types confer a relatively low risk of further clinical attacks, except for ring-like lesions and the combination with MS-typical lesions.

  10. Quantifying brain tissue volume in multiple sclerosis with automated lesion segmentation and filling.

    PubMed

    Valverde, Sergi; Oliver, Arnau; Roura, Eloy; Pareto, Deborah; Vilanova, Joan C; Ramió-Torrentà, Lluís; Sastre-Garriga, Jaume; Montalban, Xavier; Rovira, Àlex; Lladó, Xavier

    2015-01-01

    Lesion filling has been successfully applied to reduce the effect of hypo-intense T1-w Multiple Sclerosis (MS) lesions on automatic brain tissue segmentation. However, a study of fully automated pipelines incorporating lesion segmentation and lesion filling on tissue volume analysis has not yet been performed. Here, we analyzed the % of error introduced by automating the lesion segmentation and filling processes in the tissue segmentation of 70 clinically isolated syndrome patient images. First of all, images were processed using the LST and SLS toolkits with different pipeline combinations that differed in either automated or manual lesion segmentation, and lesion filling or masking out lesions. Then, images processed following each of the pipelines were segmented into gray matter (GM) and white matter (WM) using SPM8, and compared with the same images where expert lesion annotations were filled before segmentation. Our results showed that fully automated lesion segmentation and filling pipelines reduced significantly the % of error in GM and WM volume on images of MS patients, and performed similarly to the images where expert lesion annotations were masked before segmentation. In all the pipelines, the amount of misclassified lesion voxels was the main cause in the observed error in GM and WM volume. However, the % of error was significantly lower when automatically estimated lesions were filled and not masked before segmentation. These results are relevant and suggest that LST and SLS toolboxes allow the performance of accurate brain tissue volume measurements without any kind of manual intervention, which can be convenient not only in terms of time and economic costs, but also to avoid the inherent intra/inter variability between manual annotations.

  11. Quantifying brain tissue volume in multiple sclerosis with automated lesion segmentation and filling

    PubMed Central

    Valverde, Sergi; Oliver, Arnau; Roura, Eloy; Pareto, Deborah; Vilanova, Joan C.; Ramió-Torrentà, Lluís; Sastre-Garriga, Jaume; Montalban, Xavier; Rovira, Àlex; Lladó, Xavier

    2015-01-01

    Lesion filling has been successfully applied to reduce the effect of hypo-intense T1-w Multiple Sclerosis (MS) lesions on automatic brain tissue segmentation. However, a study of fully automated pipelines incorporating lesion segmentation and lesion filling on tissue volume analysis has not yet been performed. Here, we analyzed the % of error introduced by automating the lesion segmentation and filling processes in the tissue segmentation of 70 clinically isolated syndrome patient images. First of all, images were processed using the LST and SLS toolkits with different pipeline combinations that differed in either automated or manual lesion segmentation, and lesion filling or masking out lesions. Then, images processed following each of the pipelines were segmented into gray matter (GM) and white matter (WM) using SPM8, and compared with the same images where expert lesion annotations were filled before segmentation. Our results showed that fully automated lesion segmentation and filling pipelines reduced significantly the % of error in GM and WM volume on images of MS patients, and performed similarly to the images where expert lesion annotations were masked before segmentation. In all the pipelines, the amount of misclassified lesion voxels was the main cause in the observed error in GM and WM volume. However, the % of error was significantly lower when automatically estimated lesions were filled and not masked before segmentation. These results are relevant and suggest that LST and SLS toolboxes allow the performance of accurate brain tissue volume measurements without any kind of manual intervention, which can be convenient not only in terms of time and economic costs, but also to avoid the inherent intra/inter variability between manual annotations. PMID:26740917

  12. a Computational Model for Lesion Dynamics in Multiple Sclerosis of the Brain

    NASA Astrophysics Data System (ADS)

    Mohan, T. R. Krishna; Sen, Surajit; Ramanathan, Murali

    Multiple sclerosis (MS) is a chronic disabling disease of the central nervous system (CNS) that is characterized by lesions with inflammatory cells, axons with the insulating myelin sheath damaged, and axonal loss. The causes of MS are not known and there is as yet no cure. The purpose of this research was to evaluate a physically motivated network model for lesion formation in the brain. The parsimonious network model contained two elements: (i) a spatially spreading pathological process causing cell damage and death leading to neuro-degeneration and, (ii) generation of alarm signals by the damaged cells that lead to activation of programmed death of cells surrounding the lesions in an attempt to contain the spatial spread of the pathologic process. Simulation results with a range of network geometries indicated that the model was capable of describing lesion progression and arrest. The modeling results also demonstrated dynamical complexity with sensitivity to initial conditions.

  13. Detection of white matter lesions in cerebral small vessel disease

    NASA Astrophysics Data System (ADS)

    Riad, Medhat M.; Platel, Bram; de Leeuw, Frank-Erik; Karssemeijer, Nico

    2013-02-01

    White matter lesions (WML) are diffuse white matter abnormalities commonly found in older subjects and are important indicators of stroke, multiple sclerosis, dementia and other disorders. We present an automated WML detection method and evaluate it on a dataset of small vessel disease (SVD) patients. In early SVD, small WMLs are expected to be of importance for the prediction of disease progression. Commonly used WML segmentation methods tend to ignore small WMLs and are mostly validated on the basis of total lesion load or a Dice coefficient for all detected WMLs. Therefore, in this paper, we present a method that is designed to detect individual lesions, large or small, and we validate the detection performance of our system with FROC (free-response ROC) analysis. For the automated detection, we use supervised classification making use of multimodal voxel based features from different magnetic resonance imaging (MRI) sequences, including intensities, tissue probabilities, voxel locations and distances, neighborhood textures and others. After preprocessing, including co-registration, brain extraction, bias correction, intensity normalization, and nonlinear registration, ventricle segmentation is performed and features are calculated for each brain voxel. A gentle-boost classifier is trained using these features from 50 manually annotated subjects to give each voxel a probability of being a lesion voxel. We perform ROC analysis to illustrate the benefits of using additional features to the commonly used voxel intensities; significantly increasing the area under the curve (Az) from 0.81 to 0.96 (p<0.05). We perform the FROC analysis by testing our classifier on 50 previously unseen subjects and compare the results with manual annotations performed by two experts. Using the first annotator results as our reference, the second annotator performs at a sensitivity of 0.90 with an average of 41 false positives per subject while our automated method reached the same

  14. Non-locally regularized segmentation of multiple sclerosis lesion from multi-channel MRI data.

    PubMed

    Gao, Jingjing; Li, Chunming; Feng, Chaolu; Xie, Mei; Yin, Yilong; Davatzikos, Christos

    2014-10-01

    Segmentation of multiple sclerosis (MS) lesion is important for many neuroimaging studies. In this paper, we propose a novel algorithm for automatic segmentation of MS lesions from multi-channel MR images (T1W, T2W and FLAIR images). The proposed method is an extension of Li et al.'s algorithm in [1], which only segments the normal tissues from T1W images. The proposed method is aimed to segment MS lesions, while normal tissues are also segmented and bias field is estimated to handle intensity inhomogeneities in the images. Another contribution of this paper is the introduction of a nonlocal means technique to achieve spatially regularized segmentation, which overcomes the influence of noise. Experimental results have demonstrated the effectiveness and advantages of the proposed algorithm.

  15. Multispectral analysis and visualization of multiple sclerosis lesions in MR volumes of the brain

    NASA Astrophysics Data System (ADS)

    Mitchell, Ross; Karlik, Stephen J.; Lee, Donald H.; Fenster, Aaron

    1993-09-01

    MRI is a valuable tool in the diagnosis of multiple sclerosis (MS). Standard MR protocols for imaging MS produce proton density (PD) and T2 weighted images of the same slice in the brain. While these image pairs provide valuable information about MS lesions, they are two dimensional (2-D) while lesions are three dimensional (3-D). Furthermore, the vast amount of data produced in an MR exam for MS makes routine analysis and comparison of the image pairs difficult. Therefore, we have developed a computerized system which employs multi- spectral analysis techniques to allow interactive 3-D analysis of MR data by radiologists and neurologists. We have used our system to classify and analyze four MR exams of a chronic- progressive MS patient taken over an 18 month period. Comparison of volume renderings of classified white matter, grey matter and MS lesions at each exam date provide information about the changes in individual lesions, and total lesion burden. Analysis of the intensity distributions of large MS lesions reveals that they have a wide range of PD/T2 weighted intensities, and some contain a higher PD/longer T2 'core' perhaps corresponding to edema.

  16. Analysis of geometrical relations between multiple sclerosis lesions and brain vasculature

    NASA Astrophysics Data System (ADS)

    Kozinska, Dorota E.; Holland, Christopher; Krissian, Karl; Westin, Carl-Fredrik; Guttmann, Charles R. G.

    2004-04-01

    Due to histological evidence of the fundamental role of the cerebral vessels in white matter abnormalities, recently there has been an increased interest in analyzing the relationship between brain white matter lesions in multiple sclerosis (MS) and brain vasculature. We developed a method for visualization and measurement of geometrical relationships between MS lesions and the brain vessels imaged with magnetic resonance (MR) imaging techniques. Using MR images we create surface models of lesions and vessels that constitute a base for quantitative analysis. In this work we analyze correlation between basic lesion geometrical characteristics and two features: 1) distances to vessels, and 2) vessel caliber. For the former, we compute a distance map from the vessel structure, such that each voxel stores its distance vector to the closest vessel. This allows the measurements of Euclidean distances to the closest vessels. For the latter, we compute a radius map in which each voxel stores the radius of its closest vessel. It is used to measure distribution of lesions with respect to the vessel caliber. We compute and analyze relations between the basic geometrical characteristics of lesions and the closest vessels locations and calibers. To demonstrate the feasibility of the developed technique we present results from the study of 3 MS cases.

  17. Multiple sclerosis lesion quantification in MR images by using vectorial scale-based relative fuzzy connectedness

    NASA Astrophysics Data System (ADS)

    Zhuge, Ying; Udupa, Jayaram K.; Nyul, Laszlo G.

    2004-05-01

    This paper presents a methodology for segmenting PD- and T2-weighted brain magnetic resonance (MR) images of multiple sclerosis (MS) patients into white matter (WM), gray matter (GM), cerebrospinal fluid (CSF), and MS lesions. For a given vectorial image (with PD- and T2-weighted components) to be segmented, we perform first intensity inhomogeneity correction and standardization prior to segmentation. Absolute fuzzy connectedness and certain morphological operations are utilized to generate the brain intracranial mask. The optimum thresholding method is applied to the product image (the image in which voxel values represent T2 value x PD value) to automatically recognize potential MS lesion sites. Then, the recently developed technique -- vectorial scale-based relative fuzzy connectedness -- is utilized to segment all voxels within the brain intracranial mask into WM, GM, CSF, and MS lesion regions. The number of segmented lesions and the volume of each lesion are finally output as well as the volume of other tissue regions. The method has been tested on 10 clinical brain MRI data sets of MS patients. An accuracy of better than 96% has been achieved. The preliminary results indicate that its performance is better than that of the k-nearest neighbors (kNN) method.

  18. Classification and analysis of multiple sclerosis lesions in spin-echo MR exams

    NASA Astrophysics Data System (ADS)

    Mitchell, Ross; Karlik, Stephen J.; Lee, Donald H.; Fenster, Aaron

    1994-09-01

    The high resolution and excellent soft tissue contrast of Magnetic Resonance Imaging (MRI) have enabled direct, non- invasive visualization of Multiple Sclerosis (MS) lesions in vivo. This has allowed quantification of changes in the appearance of lesions in MR exams to be used as a measure of disease state. Nevertheless, accurate quantification techniques are subject to inter- and intra-operator variability, which may hinder monitoring of disease progression. We have developed a computer program to aid an experienced operator in the quantification of MS lesions in spin-echo MR exams. Assisted and manual quantification were used to study inter-operator and intra-operator variability under known conditions in exams of a test phantom, and under clinical conditions in 1.5T and 0.5T exams of an MS patient. Results of the phantom study show that accuracy was improved by assisted quantification. The patient exam results indicate that assisted quantification reduced both inter-operator and intra-operator variability, while quantification in 0.5T exams reduced the variability of manual quantification, but had no significant effect upon assisted quantification. Application of assisted quantification to the analysis and visualization of two large periventricular lesions reveals subtle changes over time in the internal composition of these apparently static lesions.

  19. Assessment of Multiple Sclerosis Lesions with Spherical Harmonics: Comparison of MR Imaging and Pathologic Findings1

    PubMed Central

    Goldberg-Zimring, Daniel; Shalmon, Bruria; Zou, Kelly H.; Azhari, Haim; Nass, Dvora; Achiron, Anat

    2005-01-01

    Spherical harmonics (SH) were used to approximate the volume and three-dimensional geometry of multiple sclerosis (MS) lesions in deceased patients. The institutional ethical committee does not require its approval for studies involving pathologic specimens. Pathologic findings were used as the reference standard. In addition, lesion volume was measured with cylindrical approximation (CA). Volumetric comparisons of biases were based on summary statistics, Spearman correlation, Wilcoxon test, and two-way analysis of variance. Shape comparison metrics included mean distance and Dice similarity coefficient (DSC). Eight of 11 lesions had smaller biases with SH method (P < .001). Median biases with SH and CA did not differ significantly, as compared with pathologic findings (r = 1.00 vs 0.99, respectively). Variances of the biases were significantly smaller for SH (P =.04). Ranges of normalized distance and DSC were 0.1%–2.5% and 75%–96%, respectively. Mean DSC was significantly higher than 70% (P < .001). SH method provided unbiased lesion volume and added geometric information that may enable a better understanding of the pathogenesis and lesion evolution over time. PMID:15833980

  20. Characteristics of multiple sclerosis patient stance control disorders, measured by means of posturography and related to brainstem lesions

    PubMed Central

    Alpini, Dario; Berardino, Federica Di; Mattei, Valentina; Caputo, Domenico; Schalek, Peter; Cesarani, Antonio

    2012-01-01

    Balance disorders are commonly observed during the course of multiple sclerosis (MS). The aim of this study is to report characteristics of MS patient stance control disorders, measured by means of posturography and related to the brainstem lesions. Thirty-eight patients affected by MS, mildly to moderately disable according to Kurtzke's Expanded Disability Status Scale, underwent a complete clinical neurological and vestibular evaluation and brain MRI scanning. All patients were then tested on a static posturography platform (Tetrax, Israel) in four conditions: eyes open and eyes closed standing on a firm surface and on a foam pad. Clinical and/or magnetic resonance imaging evidence of brainstem involvement was observed in 55.3% of patients. When brainstem lesion was detected, Fourier analysis showed a typical pattern characterized by inversion of the 0–0.1 Hz and 0.1–0.25 Hz frequency bands. In conclusion, MS leads to pervasive postural disturbances in the majority of subjects, including the visuo-vestibular loops and proprioception involving vestibulo-spinal pathways in at least 55.3% of patients. Our results may also suggest the presence of Fourier inversion in patients with brainstem lesions. PMID:26557338

  1. Motor neuron degeneration in spastic paraplegia 11 mimics amyotrophic lateral sclerosis lesions.

    PubMed

    Denora, Paola S; Smets, Katrien; Zolfanelli, Federica; Ceuterick-de Groote, Chantal; Casali, Carlo; Deconinck, Tine; Sieben, Anne; Gonzales, Michael; Zuchner, Stephan; Darios, Frédéric; Peeters, Dirk; Brice, Alexis; Malandrini, Alessandro; De Jonghe, Peter; Santorelli, Filippo M; Stevanin, Giovanni; Martin, Jean-Jacques; El Hachimi, Khalid H

    2016-06-01

    The most common form of autosomal recessive hereditary spastic paraplegia is caused by mutations in the SPG11/KIAA1840 gene on chromosome 15q. The nature of the vast majority of SPG11 mutations found to date suggests a loss-of-function mechanism of the encoded protein, spatacsin. The SPG11 phenotype is, in most cases, characterized by a progressive spasticity with neuropathy, cognitive impairment and a thin corpus callosum on brain MRI. Full neuropathological characterization has not been reported to date despite the description of >100 SPG11 mutations. We describe here the clinical and pathological features observed in two unrelated females, members of genetically ascertained SPG11 families originating from Belgium and Italy, respectively. We confirm the presence of lesions of motor tracts in medulla oblongata and spinal cord associated with other lesions of the central nervous system. Interestingly, we report for the first time pathological hallmarks of SPG11 in neurons that include intracytoplasmic granular lysosome-like structures mainly in supratentorial areas, and others in subtentorial areas that are partially reminiscent of those observed in amyotrophic lateral sclerosis, such as ubiquitin and p62 aggregates, except that they are never labelled with anti-TDP-43 or anti-cystatin C. The neuropathological overlap with amyotrophic lateral sclerosis, associated with some shared clinical manifestations, opens up new fields of investigation in the physiopathological continuum of motor neuron degeneration. PMID:27016404

  2. Site and size of multiple sclerosis lesions predict enhanced or decreased female orgasmic function.

    PubMed

    Winder, Klemens; Seifert, Frank; Koehn, Julia; Deutsch, Martina; Engelhorn, Tobias; Dörfler, Arnd; Lee, De-Hyung; Linker, Ralf A; Hilz, Max J

    2015-12-01

    Neuroimaging identified brain areas involved in female orgasm. In women with multiple sclerosis (MS), associations between orgasmic function and the site and size of MS-related magnetic resonance imaging (MRI) changes are undetermined. This study intended to correlate MS-associated cerebral lesion load and location with clinical scores of female orgasmic function. In 50 women with MS (mean age 37.0 ± 9.9 years), we assessed Female Sexual Function Index (FSFI) scores for orgasmic frequency, difficulty and satisfaction. We determined disease duration, Expanded Disability Status Scale (EDSS) scores, and cerebral MS-lesion load and location using T2-weighed 1.5 T MRIs. We correlated FSFI scores for orgasm with patient age, disease duration, EDSS scores, and cerebral MS-lesion load (Spearman rank correlation; significance: p < 0.05). FSFI scores for orgasm correlated inversely with MS-lesion load in the left temporal periventricular white matter and right middle-inferior occipital area, but directly with MS-lesion load in the right frontal primary motor cortex, left prefrontal/inferior frontal cortex, right amygdala, left temporal middle-inferior and fusiform areas, and midbrain. FSFI scores for orgasm did not correlate with patient age, disease duration and EDSS scores (p > 0.05). In conclusion, our results indicate that MS-lesions in left temporal periventricular and right visual association areas deteriorate orgasmic function. In contrast, direct correlations between frontotemporal or midbrain lesions and higher FSFI scores, indicating enhanced or disinhibited orgasmic function, suggest that these brain regions normally buffer orgasmic responses. Moreover, our results indicate that orgasmic dysfunction in women with MS evolves independently of disease duration and physical disability. PMID:26459094

  3. Computer detection of stellate lesions in mammograms

    NASA Astrophysics Data System (ADS)

    Kegelmeyer, W. Philip, Jr.

    1992-06-01

    The three primary signs for which radiologists search when screening mammograms for breast cancer are stellate lesions, microcalcifications, and circumscribed lesions. Stellate lesions are of particular importance, as they are almost always associated with a malignancy. Further, they are often indicated only by subtle architectural distortions and so are in general easier to miss than the other signs. We have developed a method for the automatic detection of stellate lesions in digitized mammograms, and have tested them on image data where the presence or absence of malignancies is known. We extract image features from the known images, use them to grow binary decision trees, and use those trees to label each pixel of new mammograms with its probability of being located on an abnormality. The primary feature for the detection of stellate lesions is ALOE, analysis of local oriented edges, which is derived from an analysis of the histogram of edge orientations in local windows. Other features, based on the Laws texture energy measures, have been developed to respond to normal tissue, and so improve the false alarm performance of the entire system.

  4. αβ T-cell receptors from multiple sclerosis brain lesions show MAIT cell–related features

    PubMed Central

    Held, Kathrin; Bhonsle-Deeng, Latika; Siewert, Katherina; Sato, Wakiro; Beltrán, Eduardo; Schmidt, Stephan; Rühl, Geraldine; Ng, Judy K.M.; Engerer, Peter; Moser, Markus; Klinkert, Wolfgang E.F.; Babbe, Holger; Misgeld, Thomas; Wekerle, Hartmut; Laplaud, David-Axel; Hohlfeld, Reinhard

    2015-01-01

    Objectives: To characterize phenotypes of T cells that accumulated in multiple sclerosis (MS) lesions, to compare the lesional T-cell receptor (TCR) repertoire of T-cell subsets to peripheral blood, and to identify paired α and β chains from single CD8+ T cells from an index patient who we followed for 18 years. Methods: We combined immunohistochemistry, laser microdissection, and single-cell multiplex PCR to characterize T-cell subtypes and identify paired TCRα and TCRβ chains from individual brain-infiltrating T cells in frozen brain sections. The lesional and peripheral TCR repertoires were analyzed by pyrosequencing. Results: We found that a TCR Vβ1+ T-cell population that was strikingly expanded in active brain lesions at clinical onset comprises several subclones expressing distinct yet closely related Vα7.2+ α chains, including a canonical Vα7.2-Jα33 chain of mucosal-associated invariant T (MAIT) cells. Three other α chains bear striking similarities in their antigen-recognizing, hypervariable complementarity determining region 3. Longitudinal repertoire studies revealed that the TCR chains that were massively expanded in brain at onset persisted for several years in blood or CSF but subsequently disappeared except for the canonical Vα7.2+ MAIT cell and a few other TCR sequences that were still detectable in blood after 18 years. Conclusions: Our observation that a massively expanded TCR Vβ1-Jβ2.3 chain paired with distinct yet closely related canonical or atypical MAIT cell–related α chains strongly points to an antigen-driven process in early active MS brain lesions. PMID:25977934

  5. Sodium MRI in Multiple Sclerosis is Compatible with Intracellular Sodium Accumulation and Inflammation-Induced Hyper-Cellularity of Acute Brain Lesions

    PubMed Central

    Biller, Armin; Pflugmann, Isabella; Badde, Stephanie; Diem, Ricarda; Wildemann, Brigitte; Nagel, Armin M.; Jordan, J.; Benkhedah, Nadia; Kleesiek, Jens

    2016-01-01

    The cascade of inflammatory pathogenetic mechanisms in multiple sclerosis (MS) has no specific conventional MRI correlates. Clinicians therefore stipulate improved imaging specificity to define the pathological substrates of MS in vivo including mapping of intracellular sodium accumulation. Based upon preclinical findings and results of previous sodium MRI studies in MS patients we hypothesized that the fluid-attenuated sodium signal differs between acute and chronic lesions. We acquired brain sodium and proton MRI data of N = 29 MS patients; lesion type was defined by the presence or absence of contrast enhancement. N = 302 MS brain lesions were detected, and generalized linear mixed models were applied to predict lesion type based on sodium signals; thereby controlling for varying numbers of lesions among patients and confounding variables such as age and medication. Hierarchical model comparisons revealed that both sodium signals average tissue (χ2(1) = 27.89, p < 0.001) and fluid-attenuated (χ2(1) = 5.76, p = 0.016) improved lesion type classification. Sodium MRI signals were significantly elevated in acute compared to chronic lesions compatible with intracellular sodium accumulation in acute MS lesions. If confirmed in further studies, sodium MRI could serve as biomarker for diagnostic assessment of MS, and as readout parameter in clinical trials promoting attenuation of chronic inflammation. PMID:27507776

  6. Sodium MRI in Multiple Sclerosis is Compatible with Intracellular Sodium Accumulation and Inflammation-Induced Hyper-Cellularity of Acute Brain Lesions.

    PubMed

    Biller, Armin; Pflugmann, Isabella; Badde, Stephanie; Diem, Ricarda; Wildemann, Brigitte; Nagel, Armin M; Jordan, J; Benkhedah, Nadia; Kleesiek, Jens

    2016-01-01

    The cascade of inflammatory pathogenetic mechanisms in multiple sclerosis (MS) has no specific conventional MRI correlates. Clinicians therefore stipulate improved imaging specificity to define the pathological substrates of MS in vivo including mapping of intracellular sodium accumulation. Based upon preclinical findings and results of previous sodium MRI studies in MS patients we hypothesized that the fluid-attenuated sodium signal differs between acute and chronic lesions. We acquired brain sodium and proton MRI data of N = 29 MS patients; lesion type was defined by the presence or absence of contrast enhancement. N = 302 MS brain lesions were detected, and generalized linear mixed models were applied to predict lesion type based on sodium signals; thereby controlling for varying numbers of lesions among patients and confounding variables such as age and medication. Hierarchical model comparisons revealed that both sodium signals average tissue (χ(2)(1) = 27.89, p < 0.001) and fluid-attenuated (χ(2)(1) = 5.76, p = 0.016) improved lesion type classification. Sodium MRI signals were significantly elevated in acute compared to chronic lesions compatible with intracellular sodium accumulation in acute MS lesions. If confirmed in further studies, sodium MRI could serve as biomarker for diagnostic assessment of MS, and as readout parameter in clinical trials promoting attenuation of chronic inflammation. PMID:27507776

  7. Natalizumab plus interferon beta-1a reduces lesion formation in relapsing multiple sclerosis.

    PubMed

    Radue, Ernst-Wilhelm; Stuart, William H; Calabresi, Peter A; Confavreux, Christian; Galetta, Steven L; Rudick, Richard A; Lublin, Fred D; Weinstock-Guttman, Bianca; Wynn, Daniel R; Fisher, Elizabeth; Papadopoulou, Athina; Lynn, Frances; Panzara, Michael A; Sandrock, Alfred W

    2010-05-15

    The SENTINEL study showed that the addition of natalizumab improved outcomes for patients with relapsing multiple sclerosis (MS) who had experienced disease activity while receiving interferon beta-1a (IFNbeta-1a) alone. Previously unreported secondary and tertiary magnetic resonance imaging (MRI) measures are presented here. Patients received natalizumab 300 mg (n=589) or placebo (n=582) intravenously every 4 weeks plus IFNbeta-1a 30 microg intramuscularly once weekly. Annual MRI scans allowed comparison of a range of MRI end points versus baseline. Over 2 years, 67% of patients receiving natalizumab plus IFNbeta-1a remained free of new or enlarging T2-lesions compared with 30% of patients receiving IFNbeta-1a alone. The mean change from baseline in T2 lesion volume over 2 years decreased in patients receiving natalizumab plus IFNbeta-1a and increased in those receiving IFNbeta-1a alone (-277.5mm(3) versus 525.6mm(3); p<0.001). Compared with IFNbeta-1a alone, add-on natalizumab therapy resulted in a smaller increase in mean T1-hypointense lesion volume after 2 years (1821.3mm(3) versus 2210.5mm(3); p<0.001), a smaller mean number of new T1-hypointense lesions over 2 years (2.3 versus 4.1; p<0.001), and a slower rate of brain atrophy during the second year of therapy (-0.31% versus -0.40%; p=0.020). Natalizumab add-on therapy reduced gadolinium-enhancing, T1-hypointense, and T2 MRI lesion activity and slowed brain atrophy progression in patients with relapsing MS who experienced disease activity despite treatment with IFNbeta-1a alone. PMID:20236661

  8. Quantitative assessment of multiple sclerosis lesion load using CAD and expert input

    NASA Astrophysics Data System (ADS)

    Gertych, Arkadiusz; Wong, Alexis; Sangnil, Alan; Liu, Brent J.

    2008-03-01

    Multiple sclerosis (MS) is a frequently encountered neurological disease with a progressive but variable course affecting the central nervous system. Outline-based lesion quantification in the assessment of lesion load (LL) performed on magnetic resonance (MR) images is clinically useful and provides information about the development and change reflecting overall disease burden. Methods of LL assessment that rely on human input are tedious, have higher intra- and inter-observer variability and are more time-consuming than computerized automatic (CAD) techniques. At present it seems that methods based on human lesion identification preceded by non-interactive outlining by CAD are the best LL quantification strategies. We have developed a CAD that automatically quantifies MS lesions, displays 3-D lesion map and appends radiological findings to original images according to current DICOM standard. CAD is also capable to display and track changes and make comparison between patient's separate MRI studies to determine disease progression. The findings are exported to a separate imaging tool for review and final approval by expert. Capturing and standardized archiving of manual contours is also implemented. Similarity coefficients calculated from quantities of LL in collected exams show a good correlation of CAD-derived results vs. those incorporated as expert's reading. Combining the CAD approach with an expert interaction may impact to the diagnostic work-up of MS patients because of improved reproducibility in LL assessment and reduced time for single MR or comparative exams reading. Inclusion of CAD-generated outlines as DICOM-compliant overlays into the image data can serve as a better reference in MS progression tracking.

  9. A longitudinal model for magnetic resonance imaging lesion count data in multiple sclerosis patients.

    PubMed

    MacKay Altman, Rachel; Petkau, A John; Vrecko, Dean; Smith, Alex

    2012-02-28

    Magnetic resonance imaging (MRI) data are routinely collected at multiple time points during phase 2 clinical trials in multiple sclerosis. However, these data are typically summarized into a single response for each patient before analysis. Models based on these summary statistics do not allow the exploration of the trade-off between numbers of patients and numbers of scans per patient or the development of optimal schedules for MRI scanning. To address these limitations, in this paper, we develop a longitudinal model to describe one MRI outcome: the number of lesions observed on an individual MRI scan. We motivate our choice of a mixed hidden Markov model based both on novel graphical diagnostic methods applied to five real data sets and on conceptual considerations. Using this model, we compare the performance of a number of different tests of treatment effect. These include standard parametric and nonparametric tests, as well as tests based on the new model. We conduct an extensive simulation study using data generated from the longitudinal model to investigate the parameters that affect test performance and to assess size and power. We determine that the parameters of the hidden Markov chain do not substantially affect the performance of the tests. Furthermore, we describe conditions under which likelihood ratio tests based on the longitudinal model appreciably outperform the standard tests based on summary statistics. These results establish that the new model is a valuable practical tool for designing and analyzing multiple sclerosis clinical trials. PMID:21964585

  10. A probabilistic framework for the spatio-temporal segmentation of multiple sclerosis lesions in MR images of the brain

    NASA Astrophysics Data System (ADS)

    Greenspan, Hayit; Mayer, Arnaldo; Shahar, Allon

    2003-05-01

    In this paper we describe the application of a novel statistical image-sequence (video) modeling scheme to sequences of multiple sclerosis (MS) images taken over time. A unique key feature of the proposed framework is the analysis of the image-sequence input as a single entity as opposed to a sequence of separate frames. The extracted space-time regions allow for the detection and identification of disease events and processes, such as the appearance and progression of lesions. According to the proposed methodology, coherent space-time regions in the feature space, and corresponding coherent segments in the video content are extracted by unsupervised clustering via Gaussian mixture modeling (GMM). The parameters of the GMM are determined via the maximum likelihood principle and the Expectation-Maximization (EM) algorithm. The clustering of the image sequence yields a collection of regions (blobs) in a four-dimensional feature space (including intensity, position (x,y), and time). Regions corresponding to MS lesions are automatically identified based on criteria regarding the mean intensity and the size variability over time. The proposed methodology was applied to a registered sequence of 24 T2-weighted MR images acquired from an MS patient over a period of approximately a year. Examples of preliminary qualitative results are shown.

  11. Detectability of pathological lesions in lumbar spine radiography

    NASA Astrophysics Data System (ADS)

    Tingberg, Anders; Bath, Magnus; Ruschin, Mark; Grahn, Anna; Besjakov, Jack; Borjesson, Sara; Hakansson, Markus; Mattsson, Soren; Mansson, Lars Gunnar

    2005-04-01

    Thirty images with added simulated pathological lesions at two different dose levels (100% and 10% dose) were evaluated with the free-response forced error experiment by nine experienced radiologists. The simulated pathological lesions present in the images were classified according to four different parameters: the position within the lumbar spine, possibility to perform a symmetrical (left-right) comparison, the lesion contrast, and the complexity of the surrounding background where the lesion was situated. The detectability of each lesion was calculated as the fraction of radiologists who successfully detected the lesion before a false positive error was made. The influence of each of the four parameters on lesion detectability was investigated. The results of the study show that the influence of lesion contrast is the most important factor for detectability. Since the dose level had a limited effect on detectability, large dose savings can be made without reducing the detectability of pathological lesions in lumbar spine radiography.

  12. Variant of multiple sclerosis with dementia and tumefactive demyelinating brain lesions

    PubMed Central

    Hamed, Sherifa A

    2015-01-01

    We describe an unusual clinical and diagnostic feature of a patient with multiple sclerosis (MS). A 25-year-old woman was admitted to the Neurology department (December 2009) with one month history of rapid cognitive deterioration. She had poor cognition, dysphasia, reduction in visual acuity and temporal pallor of the optic discs. She had prolonged latencies of P100 component of visual evoked potentials (VEPs). Magnetic resonance imaging (MRI)-brain showed multifocal large (≥ 3 cm) white-matter hypointense lesions in T1W and hyperintense in T2W and fluid-attenuated inversion recovery images and patchy enhancement. A diagnosis of tumefactive MS was given. She received two consecutive 5-d courses of 1 g daily intravenous methylprednisolone for 2 mo and oral prednisolone in dose of 80 mg twice/daily in between. At the 3rd month, Mini Mental State Examination and VEPs returned to normal but not the MRI. Patient continued oral steroids after hospital discharge (March 2010) for 9 mo with significant MRI improvement after which tapering of steroids started for a year. The patient refused immunomodulation therapy due to her low socioeconomic status. Neither clinical relapse nor new MRI lesions were observed throughout the next 4 years. In spite of the aggressive course of tumefactive MS variant, good prognosis may be seen in some patients. PMID:26090374

  13. Detecting circumscribed lesions with the Hough transform

    SciTech Connect

    Groshong, B.R; Kegelmeyer, W.P., Jr

    1996-01-11

    We have designed and implemented a circumscribed lesion detection algorithm, based on the Hough Transform, which will detect zero or more approximately circular structures in a mammogram over a range of radii from a few pixels to nearly the size of the breast. We address the geometrical behavior of peaks in Hough parameter space (x,y,r) for both the true radius of a circular structure in the image (r = r{sub o}), and for the parameter r as it passes through this radius. In addition, we evaluate peaks in Hough parameter space by re-analyzing the underlying mammogram in the vicinity of the circular disk indicated by the peak. Discs suggested by the resulting peaks are accumulated in a feature image, scaled by a measure of their quality. These results are then rectified with respect to image contrast extremes and average value. The result is a feature with a continuously scaled pixel level output which suggests the likelihood that a pixel is located inside a circular structure, irrespective of the radius of the structure and overall mammogram contrast. These features are evaluated fast qualitative and quantitative performance metrics which permit circumscribed lesion detection features to be initially evaluated without a full end-to-end classification experiment.

  14. Automatic iterative segmentation of multiple sclerosis lesions using Student's t mixture models and probabilistic anatomical atlases in FLAIR images.

    PubMed

    Freire, Paulo G L; Ferrari, Ricardo J

    2016-06-01

    Multiple sclerosis (MS) is a demyelinating autoimmune disease that attacks the central nervous system (CNS) and affects more than 2 million people worldwide. The segmentation of MS lesions in magnetic resonance imaging (MRI) is a very important task to assess how a patient is responding to treatment and how the disease is progressing. Computational approaches have been proposed over the years to segment MS lesions and reduce the amount of time spent on manual delineation and inter- and intra-rater variability and bias. However, fully-automatic segmentation of MS lesions still remains an open problem. In this work, we propose an iterative approach using Student's t mixture models and probabilistic anatomical atlases to automatically segment MS lesions in Fluid Attenuated Inversion Recovery (FLAIR) images. Our technique resembles a refinement approach by iteratively segmenting brain tissues into smaller classes until MS lesions are grouped as the most hyperintense one. To validate our technique we used 21 clinical images from the 2015 Longitudinal Multiple Sclerosis Lesion Segmentation Challenge dataset. Evaluation using Dice Similarity Coefficient (DSC), True Positive Ratio (TPR), False Positive Ratio (FPR), Volume Difference (VD) and Pearson's r coefficient shows that our technique has a good spatial and volumetric agreement with raters' manual delineations. Also, a comparison between our proposal and the state-of-the-art shows that our technique is comparable and, in some cases, better than some approaches, thus being a viable alternative for automatic MS lesion segmentation in MRI. PMID:27058437

  15. Automatic iterative segmentation of multiple sclerosis lesions using Student's t mixture models and probabilistic anatomical atlases in FLAIR images.

    PubMed

    Freire, Paulo G L; Ferrari, Ricardo J

    2016-06-01

    Multiple sclerosis (MS) is a demyelinating autoimmune disease that attacks the central nervous system (CNS) and affects more than 2 million people worldwide. The segmentation of MS lesions in magnetic resonance imaging (MRI) is a very important task to assess how a patient is responding to treatment and how the disease is progressing. Computational approaches have been proposed over the years to segment MS lesions and reduce the amount of time spent on manual delineation and inter- and intra-rater variability and bias. However, fully-automatic segmentation of MS lesions still remains an open problem. In this work, we propose an iterative approach using Student's t mixture models and probabilistic anatomical atlases to automatically segment MS lesions in Fluid Attenuated Inversion Recovery (FLAIR) images. Our technique resembles a refinement approach by iteratively segmenting brain tissues into smaller classes until MS lesions are grouped as the most hyperintense one. To validate our technique we used 21 clinical images from the 2015 Longitudinal Multiple Sclerosis Lesion Segmentation Challenge dataset. Evaluation using Dice Similarity Coefficient (DSC), True Positive Ratio (TPR), False Positive Ratio (FPR), Volume Difference (VD) and Pearson's r coefficient shows that our technique has a good spatial and volumetric agreement with raters' manual delineations. Also, a comparison between our proposal and the state-of-the-art shows that our technique is comparable and, in some cases, better than some approaches, thus being a viable alternative for automatic MS lesion segmentation in MRI.

  16. Lesion registration for longitudinal disease tracking in an imaging informatics-based multiple sclerosis eFolder

    NASA Astrophysics Data System (ADS)

    Ma, Kevin; Liu, Joseph; Zhang, Xuejun; Lerner, Alex; Shiroishi, Mark; Amezcua, Lilyana; Liu, Brent

    2016-03-01

    We have designed and developed a multiple sclerosis eFolder system for patient data storage, image viewing, and automatic lesion quantification results stored in DICOM-SR format. The web-based system aims to be integrated in DICOM-compliant clinical and research environments to aid clinicians in patient treatments and data analysis. The system needs to quantify lesion volumes, identify and register lesion locations to track shifts in volume and quantity of lesions in a longitudinal study. In order to perform lesion registration, we have developed a brain warping and normalizing methodology using Statistical Parametric Mapping (SPM) MATLAB toolkit for brain MRI. Patients' brain MR images are processed via SPM's normalization processes, and the brain images are analyzed and warped according to the tissue probability map. Lesion identification and contouring are completed by neuroradiologists, and lesion volume quantification is completed by the eFolder's CAD program. Lesion comparison results in longitudinal studies show key growth and active regions. The results display successful lesion registration and tracking over a longitudinal study. Lesion change results are graphically represented in the web-based user interface, and users are able to correlate patient progress and changes in the MRI images. The completed lesion and disease tracking tool would enable the eFolder to provide complete patient profiles, improve the efficiency of patient care, and perform comprehensive data analysis through an integrated imaging informatics system.

  17. Relating multi-sequence longitudinal intensity profiles and clinical covariates in incident multiple sclerosis lesions.

    PubMed

    Sweeney, Elizabeth M; Shinohara, Russell T; Dewey, Blake E; Schindler, Matthew K; Muschelli, John; Reich, Daniel S; Crainiceanu, Ciprian M; Eloyan, Ani

    2016-01-01

    The formation of multiple sclerosis (MS) lesions is a complex process involving inflammation, tissue damage, and tissue repair - all of which are visible on structural magnetic resonance imaging (MRI) and potentially modifiable by pharmacological therapy. In this paper, we introduce two statistical models for relating voxel-level, longitudinal, multi-sequence structural MRI intensities within MS lesions to clinical information and therapeutic interventions: (1) a principal component analysis (PCA) and regression model and (2) function-on-scalar regression models. To do so, we first characterize the post-lesion incidence repair process on longitudinal, multi-sequence structural MRI from 34 MS patients as voxel-level intensity profiles. For the PCA regression model, we perform PCA on the intensity profiles to develop a voxel-level biomarker for identifying slow and persistent, long-term intensity changes within lesion tissue voxels. The proposed biomarker's ability to identify such effects is validated by two experienced clinicians (a neuroradiologist and a neurologist). On a scale of 1 to 4, with 4 being the highest quality, the neuroradiologist gave the score on the first PC a median quality rating of 4 (95% CI: [4,4]), and the neurologist gave the score a median rating of 3 (95% CI: [3,3]). We then relate the biomarker to the clinical information in a mixed model framework. Treatment with disease-modifying therapies (p < 0.01), steroids (p < 0.01), and being closer to the boundary of abnormal signal intensity (p < 0.01) are all associated with return of a voxel to an intensity value closer to that of normal-appearing tissue. The function-on-scalar regression model allows for assessment of the post-incidence time points at which the covariates are associated with the profiles. In the function-on-scalar regression, both age and distance to the boundary were found to have a statistically significant association with the lesion intensities at some time point

  18. Relating multi-sequence longitudinal intensity profiles and clinical covariates in incident multiple sclerosis lesions

    PubMed Central

    Sweeney, Elizabeth M.; Shinohara, Russell T.; Dewey, Blake E.; Schindler, Matthew K.; Muschelli, John; Reich, Daniel S.; Crainiceanu, Ciprian M.; Eloyan, Ani

    2015-01-01

    The formation of multiple sclerosis (MS) lesions is a complex process involving inflammation, tissue damage, and tissue repair — all of which are visible on structural magnetic resonance imaging (MRI) and potentially modifiable by pharmacological therapy. In this paper, we introduce two statistical models for relating voxel-level, longitudinal, multi-sequence structural MRI intensities within MS lesions to clinical information and therapeutic interventions: (1) a principal component analysis (PCA) and regression model and (2) function-on-scalar regression models. To do so, we first characterize the post-lesion incidence repair process on longitudinal, multi-sequence structural MRI from 34 MS patients as voxel-level intensity profiles. For the PCA regression model, we perform PCA on the intensity profiles to develop a voxel-level biomarker for identifying slow and persistent, long-term intensity changes within lesion tissue voxels. The proposed biomarker's ability to identify such effects is validated by two experienced clinicians (a neuroradiologist and a neurologist). On a scale of 1 to 4, with 4 being the highest quality, the neuroradiologist gave the score on the first PC a median quality rating of 4 (95% CI: [4,4]), and the neurologist gave the score a median rating of 3 (95% CI: [3,3]). We then relate the biomarker to the clinical information in a mixed model framework. Treatment with disease-modifying therapies (p < 0.01), steroids (p < 0.01), and being closer to the boundary of abnormal signal intensity (p < 0.01) are all associated with return of a voxel to an intensity value closer to that of normal-appearing tissue. The function-on-scalar regression model allows for assessment of the post-incidence time points at which the covariates are associated with the profiles. In the function-on-scalar regression, both age and distance to the boundary were found to have a statistically significant association with the lesion intensities at some time point

  19. A new CSF1R mutation presenting with an extensive white matter lesion mimicking primary progressive multiple sclerosis.

    PubMed

    Inui, Toshio; Kawarai, Toshitaka; Fujita, Koji; Kawamura, Kazuyuki; Mitsui, Takao; Orlacchio, Antonio; Kamada, Masaki; Abe, Takashi; Izumi, Yuishin; Kaji, Ryuji

    2013-11-15

    HDLS (Hereditary Diffuse Leukodystrophy with Spheroids) is a hereditary leukodystrophy whose main clinical manifestations include parkinsonism, spasticity, and ataxia. Genetic defects in the colony-stimulating factor 1 receptor (CSF1R) gene have been reported in many HDLS cases. The present report describes a new missense mutation Arg777Gln involving exon 18 of the CSF1R gene in a sporadic patient presenting with tumor-like lesions mimicking primary progressive multiple sclerosis. The patient was initially diagnosed with a progressive variant of multiple sclerosis and received inadequate treatments. Although most HDLS cases have a positive family history, this disease should also be suspected in sporadic patients showing unusual white matter lesions at MRI.

  20. Penalized maximum-likelihood image reconstruction for lesion detection

    NASA Astrophysics Data System (ADS)

    Qi, Jinyi; Huesman, Ronald H.

    2006-08-01

    Detecting cancerous lesions is one major application in emission tomography. In this paper, we study penalized maximum-likelihood image reconstruction for this important clinical task. Compared to analytical reconstruction methods, statistical approaches can improve the image quality by accurately modelling the photon detection process and measurement noise in imaging systems. To explore the full potential of penalized maximum-likelihood image reconstruction for lesion detection, we derived simplified theoretical expressions that allow fast evaluation of the detectability of a random lesion. The theoretical results are used to design the regularization parameters to improve lesion detectability. We conducted computer-based Monte Carlo simulations to compare the proposed penalty function, conventional penalty function, and a penalty function for isotropic point spread function. The lesion detectability is measured by a channelized Hotelling observer. The results show that the proposed penalty function outperforms the other penalty functions for lesion detection. The relative improvement is dependent on the size of the lesion. However, we found that the penalty function optimized for a 5 mm lesion still outperforms the other two penalty functions for detecting a 14 mm lesion. Therefore, it is feasible to use the penalty function designed for small lesions in image reconstruction, because detection of large lesions is relatively easy.

  1. Locally adaptive MR intensity models and MRF-based segmentation of multiple sclerosis lesions

    NASA Astrophysics Data System (ADS)

    Galimzianova, Alfiia; Lesjak, Žiga; Likar, Boštjan; Pernuš, Franjo; Špiclin, Žiga

    2015-03-01

    Neuroimaging biomarkers are an important paraclinical tool used to characterize a number of neurological diseases, however, their extraction requires accurate and reliable segmentation of normal and pathological brain structures. For MR images of healthy brains the intensity models of normal-appearing brain tissue (NABT) in combination with Markov random field (MRF) models are known to give reliable and smooth NABT segmentation. However, the presence of pathology, MR intensity bias and natural tissue-dependent intensity variability altogether represent difficult challenges for a reliable estimation of NABT intensity model based on MR images. In this paper, we propose a novel method for segmentation of normal and pathological structures in brain MR images of multiple sclerosis (MS) patients that is based on locally-adaptive NABT model, a robust method for the estimation of model parameters and a MRF-based segmentation framework. Experiments on multi-sequence brain MR images of 27 MS patients show that, compared to whole-brain model and compared to the widely used Expectation-Maximization Segmentation (EMS) method, the locally-adaptive NABT model increases the accuracy of MS lesion segmentation.

  2. Development of a web-based DICOM-SR viewer for CAD data of multiple sclerosis lesions in an imaging informatics-based efolder

    NASA Astrophysics Data System (ADS)

    Ma, Kevin; Wong, Jonathan; Zhong, Mark; Zhang, Jeff; Liu, Brent

    2014-03-01

    In the past, we have presented an imaging-informatics based eFolder system for managing and analyzing imaging and lesion data of multiple sclerosis (MS) patients, which allows for data storage, data analysis, and data mining in clinical and research settings. The system integrates the patient's clinical data with imaging studies and a computer-aided detection (CAD) algorithm for quantifying MS lesion volume, lesion contour, locations, and sizes in brain MRI studies. For compliance with IHE integration protocols, long-term storage in PACS, and data query and display in a DICOM compliant clinical setting, CAD results need to be converted into DICOM-Structured Report (SR) format. Open-source dcmtk and customized XML templates are used to convert quantitative MS CAD results from MATLAB to DICOM-SR format. A web-based GUI based on our existing web-accessible DICOM object (WADO) image viewer has been designed to display the CAD results from generated SR files. The GUI is able to parse DICOM-SR files and extract SR document data, then display lesion volume, location, and brain matter volume along with the referenced DICOM imaging study. In addition, the GUI supports lesion contour overlay, which matches a detected MS lesion with its corresponding DICOM-SR data when a user selects either the lesion or the data. The methodology of converting CAD data in native MATLAB format to DICOM-SR and displaying the tabulated DICOM-SR along with the patient's clinical information, and relevant study images in the GUI will be demonstrated. The developed SR conversion model and GUI support aim to further demonstrate how to incorporate CAD post-processing components in a PACS and imaging informatics-based environment.

  3. Optimized lesion detection in digital breast tomosynthesis

    NASA Astrophysics Data System (ADS)

    Chawla, Amarpreet S.; Samei, Ehsan; Lo, Joseph Y.

    2009-02-01

    While diagnostic improvement via breast tomosynthesis has been notable, the full potential of tomosynthesis has not yet been realized. This is because of the complex task of optimizing multiple parameters that constitute image acquisition and thus affect tomosynthesis performance. Those parameters include dose, number of angular projections, and the total angular span of those projections. In this study, we investigated the effects of acquisition parameters, independent of each other, on the overall diagnostic image quality of tomosynthesis. Five mastectomy specimens were imaged using a prototype tomosynthesis system. 25 angular projections of each specimen were acquired at 6.2 times typical single-view mammographic dose level. Images at lower dose levels were then simulated using a noise modification routine. Each projection image was supplemented with 84 simulated 3 mm 3D lesions embedded at the center of 84 non-overlapping ROIs. The projection images were then reconstructed using a filtered-back projection (FBP) algorithm at 224 different combinations of acquisition parameters to investigate which one of the many possible combinations maximized performance. Performance was evaluated in terms of a Laguerre-Gauss channelized Hotelling observer model-based measure of lesion detectability. Results showed that performance improved with an increase in the total acquisition dose level and the angular span. At a constant dose level and angular span, the performance rolled-off beyond a certain number of projections, indicating that simply increasing the number of projections in tomosynthesis may not necessarily improve its performance. The best performance was obtained with 15-17 projections spanning an angular arc of ~45° - the maximum tested in our study, and for an acquisition dose equal to single-view mammography. The optimization framework developed in this framework is applicable to other reconstruction techniques and other multi-projection systems.

  4. Phase-Sensitive Inversion-Recovery MRI Improves Longitudinal Cortical Lesion Detection in Progressive MS

    PubMed Central

    Farrell, Colleen; Fabian, Michelle; Howard, Jonathan; Riley, Claire; Miller, Aaron; Lublin, Fred; Inglese, Matilde

    2016-01-01

    Previous studies comparing phase sensitive inversion recovery (PSIR) to double inversion recovery (DIR) have demonstrated that use of PSIR improves cross-sectional in vivo detection of cortical lesions (CL) in multiple sclerosis. We studied the utility of PSIR in detection/characterization of accrual of CL over time in a 1-year longitudinal study in primary progressive multiple sclerosis (PPMS) compared to DIR. PSIR and DIR images were acquired with 3T magnetic resonance imaging (MRI) in 25 patients with PPMS and 19 healthy controls at baseline, and after 1 year in 20 patients with PPMS. CL were classified as intracortical, leucocortical or juxtacortical. Lesion counts and volumes were calculated for both time points from both sequences and compared. Correlations with measures of physical and cognitive disability were determined as well as new CL counts and volumes. Compared to DIR, PSIR led to detection of a higher number of CL involving a larger proportion of patients with PPMS both cross-sectionally (p = 0.006, 88%) and longitudinally (p = 0.007, 95%), and led to the reclassification of a third of CL seen on DIR at each time point. Interestingly, PSIR was more sensitive to new CL accumulation over time compared to DIR. PSIR is a promising technique to monitor cortical damage and disease progression in patients with PPMS over a short-term follow-up. PMID:27002529

  5. Phase-Sensitive Inversion-Recovery MRI Improves Longitudinal Cortical Lesion Detection in Progressive MS.

    PubMed

    Harel, Asaff; Ceccarelli, Antonia; Farrell, Colleen; Fabian, Michelle; Howard, Jonathan; Riley, Claire; Miller, Aaron; Lublin, Fred; Inglese, Matilde

    2016-01-01

    Previous studies comparing phase sensitive inversion recovery (PSIR) to double inversion recovery (DIR) have demonstrated that use of PSIR improves cross-sectional in vivo detection of cortical lesions (CL) in multiple sclerosis. We studied the utility of PSIR in detection/characterization of accrual of CL over time in a 1-year longitudinal study in primary progressive multiple sclerosis (PPMS) compared to DIR. PSIR and DIR images were acquired with 3T magnetic resonance imaging (MRI) in 25 patients with PPMS and 19 healthy controls at baseline, and after 1 year in 20 patients with PPMS. CL were classified as intracortical, leucocortical or juxtacortical. Lesion counts and volumes were calculated for both time points from both sequences and compared. Correlations with measures of physical and cognitive disability were determined as well as new CL counts and volumes. Compared to DIR, PSIR led to detection of a higher number of CL involving a larger proportion of patients with PPMS both cross-sectionally (p = 0.006, 88%) and longitudinally (p = 0.007, 95%), and led to the reclassification of a third of CL seen on DIR at each time point. Interestingly, PSIR was more sensitive to new CL accumulation over time compared to DIR. PSIR is a promising technique to monitor cortical damage and disease progression in patients with PPMS over a short-term follow-up.

  6. Detection of endometrial lesions by degree of linear polarization maps

    NASA Astrophysics Data System (ADS)

    Kim, Jihoon; Fazleabas, Asgerally; Walsh, Joseph T.

    2010-02-01

    Endometriosis is one of the most common causes of chronic pelvic pain and infertility and is characterized by the presence of endometrial glands and stroma outside of the uterine cavity. A novel laparoscopic polarization imaging system was designed to detect endometriosis by imaging endometrial lesions. Linearly polarized light with varying incident polarization angles illuminated endometrial lesions. Degree of linear polarization image maps of endometrial lesions were constructed by using remitted polarized light. The image maps were compared with regular laparoscopy image. The degree of linear polarization map contributed to the detection of endometriosis by revealing structures inside the lesion. The utilization of rotating incident polarization angle (IPA) for the linearly polarized light provides extended understanding of endometrial lesions. The developed polarization system with varying IPA and the collected image maps could provide improved characterization of endometrial lesions via higher visibility of the structure of the lesions and thereby improve diagnosis of endometriosis.

  7. Computer aided detection of oral lesions on CT images

    NASA Astrophysics Data System (ADS)

    Galib, S.; Islam, F.; Abir, M.; Lee, H. K.

    2015-12-01

    Oral lesions are important findings on computed tomography (CT) images. In this study, a fully automatic method to detect oral lesions in mandibular region from dental CT images is proposed. Two methods were developed to recognize two types of lesions namely (1) Close border (CB) lesions and (2) Open border (OB) lesions, which cover most of the lesion types that can be found on CT images. For the detection of CB lesions, fifteen features were extracted from each initial lesion candidates and multi layer perceptron (MLP) neural network was used to classify suspicious regions. Moreover, OB lesions were detected using a rule based image processing method, where no feature extraction or classification algorithm were used. The results were validated using a CT dataset of 52 patients, where 22 patients had abnormalities and 30 patients were normal. Using non-training dataset, CB detection algorithm yielded 71% sensitivity with 0.31 false positives per patient. Furthermore, OB detection algorithm achieved 100% sensitivity with 0.13 false positives per patient. Results suggest that, the proposed framework, which consists of two methods, has the potential to be used in clinical context, and assist radiologists for better diagnosis.

  8. Detecting Optic Atrophy in Multiple Sclerosis Patients Using New Colorimetric Analysis Software: From Idea to Application.

    PubMed

    Bambo, Maria Pilar; Garcia-Martin, Elena; Perez-Olivan, Susana; Larrosa-Povés, José Manuel; Polo-Llorens, Vicente; Gonzalez-De la Rosa, Manuel

    2016-01-01

    Neuro-ophthalmologists typically observe a temporal pallor of the optic disc in patients with multiple sclerosis. Here, we describe the emergence of an idea to quantify these optic disc color changes in multiple sclerosis patients. We recruited 12 multiple sclerosis patients with previous optic neuritis attack and obtained photographs of their optic discs. The Laguna ONhE, a new colorimetric software using hemoglobin as the reference pigment in the papilla, was used for the analysis. The papilla of these multiple sclerosis patients showed greater pallor, especially in the temporal sector. The software detected the pallor and assigned hemoglobin percentages below normal reference values. Measurements of optic disc hemoglobin levels obtained with the Laguna ONhE software program had good ability to detect optic atrophy and, consequently, axonal loss in multiple sclerosis patients. This new technology is easy to implement in routine clinical practice.

  9. Phantom experiments to improve parathyroid lesion detection

    SciTech Connect

    Nichols, Kenneth J.; Tronco, Gene G.; Tomas, Maria B.; Kunjummen, Biju D.; Siripun, Lisa; Rini, Josephine N.; Palestro, Christopher J.

    2007-12-15

    This investigation tested the hypothesis that visual analysis of iteratively reconstructed tomograms by ordered subset expectation maximization (OSEM) provides the highest accuracy for localizing parathyroid lesions using {sup 99m}Tc-sestamibi SPECT data. From an Institutional Review Board approved retrospective review of 531 patients evaluated for parathyroid localization, image characteristics were determined for 85 {sup 99m}Tc-sestamibi SPECT studies originally read as equivocal (EQ). Seventy-two plexiglas phantoms using cylindrical simulated lesions were acquired for a clinically realistic range of counts (mean simulated lesion counts of 75{+-}50 counts/pixel) and target-to-background (T:B) ratios (range=2.0 to 8.0) to determine an optimal filter for OSEM. Two experienced nuclear physicians graded simulated lesions, blinded to whether chambers contained radioactivity or plain water, and two observers used the same scale to read all phantom and clinical SPECT studies, blinded to pathology findings and clinical information. For phantom data and all clinical data, T:B analyses were not statistically different for OSEM versus FB, but visual readings were significantly more accurate than T:B (88{+-}6% versus 68{+-}6%, p=0.001) for OSEM processing, and OSEM was significantly more accurate than FB for visual readings (88{+-}6% versus 58{+-}6%, p<0.0001). These data suggest that visual analysis of iteratively reconstructed MIBI tomograms should be incorporated into imaging protocols performed to localize parathyroid lesions.

  10. Functional aspects of early brain development are preserved in tuberous sclerosis complex (TSC) epileptogenic lesions.

    PubMed

    Ruffolo, Gabriele; Iyer, Anand; Cifelli, Pierangelo; Roseti, Cristina; Mühlebner, Angelika; van Scheppingen, Jackelien; Scholl, Theresa; Hainfellner, Johannes A; Feucht, Martha; Krsek, Pavel; Zamecnik, Josef; Jansen, Floor E; Spliet, Wim G M; Limatola, Cristina; Aronica, Eleonora; Palma, Eleonora

    2016-11-01

    Tuberous sclerosis complex (TSC) is a rare multi-system genetic disease characterized by several neurological disorders, the most common of which is the refractory epilepsy caused by highly epileptogenic cortical lesions. Previous studies suggest an alteration of GABAergic and glutamatergic transmission in TSC brain indicating an unbalance of excitation/inhibition that can explain, at least in part, the high incidence of epilepsy in these patients. Here we investigate whether TSC cortical tissues could retain GABAA and AMPA receptors at early stages of human brain development thus contributing to the generation and recurrence of seizures. Given the limited availability of pediatric human brain specimens, we used the microtransplantation method of injecting Xenopus oocytes with membranes from TSC cortical tubers and control brain tissues. Moreover, qPCR was performed to investigate the expression of GABAA and AMPA receptor subunits (GABAA α1-5, β3, γ2, δ; GluA1, GluA2) and cation chloride co-transporters NKCC1 and KCC2. The evaluation of nine human cortical brain samples, from 15 gestation weeks to 15years old, showed a progressive shift towards more hyperpolarized GABAA reversal potential (EGABA). This shift was associated with a differential expression of the chloride cotransporters NKCC1 and KCC2. Furthermore, the GluA1/GluA2 mRNA ratio of expression paralleled the development process. On the contrary, in oocytes micro-transplanted with epileptic TSC tuber tissue from seven patients, neither the GABAA reversal potential nor the GluA1/GluA2 expression showed similar developmental changes. Our data indicate for the first time, that in the same cohort of TSC patients, the pattern of both GABAAR and GluA1/GluA2 functions retains features that are typical of an immature brain. These observations support the potential contribution of altered receptor function to the epileptic disorder of TSC and may suggest novel therapeutic approaches. Furthermore, our findings

  11. Functional aspects of early brain development are preserved in tuberous sclerosis complex (TSC) epileptogenic lesions.

    PubMed

    Ruffolo, Gabriele; Iyer, Anand; Cifelli, Pierangelo; Roseti, Cristina; Mühlebner, Angelika; van Scheppingen, Jackelien; Scholl, Theresa; Hainfellner, Johannes A; Feucht, Martha; Krsek, Pavel; Zamecnik, Josef; Jansen, Floor E; Spliet, Wim G M; Limatola, Cristina; Aronica, Eleonora; Palma, Eleonora

    2016-11-01

    Tuberous sclerosis complex (TSC) is a rare multi-system genetic disease characterized by several neurological disorders, the most common of which is the refractory epilepsy caused by highly epileptogenic cortical lesions. Previous studies suggest an alteration of GABAergic and glutamatergic transmission in TSC brain indicating an unbalance of excitation/inhibition that can explain, at least in part, the high incidence of epilepsy in these patients. Here we investigate whether TSC cortical tissues could retain GABAA and AMPA receptors at early stages of human brain development thus contributing to the generation and recurrence of seizures. Given the limited availability of pediatric human brain specimens, we used the microtransplantation method of injecting Xenopus oocytes with membranes from TSC cortical tubers and control brain tissues. Moreover, qPCR was performed to investigate the expression of GABAA and AMPA receptor subunits (GABAA α1-5, β3, γ2, δ; GluA1, GluA2) and cation chloride co-transporters NKCC1 and KCC2. The evaluation of nine human cortical brain samples, from 15 gestation weeks to 15years old, showed a progressive shift towards more hyperpolarized GABAA reversal potential (EGABA). This shift was associated with a differential expression of the chloride cotransporters NKCC1 and KCC2. Furthermore, the GluA1/GluA2 mRNA ratio of expression paralleled the development process. On the contrary, in oocytes micro-transplanted with epileptic TSC tuber tissue from seven patients, neither the GABAA reversal potential nor the GluA1/GluA2 expression showed similar developmental changes. Our data indicate for the first time, that in the same cohort of TSC patients, the pattern of both GABAAR and GluA1/GluA2 functions retains features that are typical of an immature brain. These observations support the potential contribution of altered receptor function to the epileptic disorder of TSC and may suggest novel therapeutic approaches. Furthermore, our findings

  12. Lesion Load May Predict Long-Term Cognitive Dysfunction in Multiple Sclerosis Patients

    PubMed Central

    Lavorgna, Luigi; Messina, Silvia; Chisari, Clara Grazia; Ippolito, Domenico; Lanzillo, Roberta; Vacchiano, Veria; Realmuto, Sabrina; Valentino, Paola; Coniglio, Gabriella; Buccafusca, Maria; Paolicelli, Damiano; D’Ambrosio, Alessandro; Montella, Patrizia; Brescia Morra, Vincenzo; Savettieri, Giovanni; Alfano, Bruno; Gallo, Antonio; Simone, Isabella; Viterbo, Rosa; Zappia, Mario; Bonavita, Simona; Tedeschi, Gioacchino

    2015-01-01

    Background Magnetic Resonance Imaging (MRI) techniques provided evidences into the understanding of cognitive impairment (CIm) in Multiple Sclerosis (MS). Objectives To investigate the role of white matter (WM) and gray matter (GM) in predicting long-term CIm in a cohort of MS patients. Methods 303 out of 597 patients participating in a previous multicenter clinical-MRI study were enrolled (49.4% were lost at follow-up). The following MRI parameters, expressed as fraction (f) of intracranial volume, were evaluated: cerebrospinal fluid (CSF-f), WM-f, GM-f and abnormal WM (AWM-f), a measure of lesion load. Nine years later, cognitive status was assessed in 241 patients using the Symbol Digit Modalities Test (SDMT), the Semantically Related Word List Test (SRWL), the Modified Card Sorting Test (MCST), and the Paced Auditory Serial Addition Test (PASAT). In particular, being SRWL a memory test, both immediate recall and delayed recall were evaluated. MCST scoring was calculated based on the number of categories, number of perseverative and non-perseverative errors. Results AWM-f was predictive of an impaired performance 9 years ahead in SDMT (OR 1.49, CI 1.12–1.97 p = 0.006), PASAT (OR 1.43, CI 1.14–1.80 p = 0.002), SRWL-immediate recall (OR 1.72 CI 1.35–2.20 p<0.001), SRWL-delayed recall (OR 1.61 CI 1.28–2.03 p<0.001), MCST-category (OR 1.52, CI 1.2–1.9 p<0.001), MCST-perseverative error(OR 1.51 CI 1.2–1.9 p = 0.001), MCST-non perseverative error (OR 1.26 CI 1.02–1.55 p = 0.032). Conclusion In our large MS cohort, focal WM damage appeared to be the most relevant predictor of the long-term cognitive outcome. PMID:25816303

  13. The Effect of Fingolimod on Conversion of Acute Gadolinium‐Enhancing Lesions to Chronic T1 Hypointensities in Multiple Sclerosis

    PubMed Central

    Oommen, Vinit V.; Tauhid, Shahamat; Healy, Brian C.; Chua, Alicia S.; Malik, Muhammad T.; Diaz‐Cruz, Camilo; Dupuy, Sheena L.; Weiner, Howard L.; Chitnis, Tanuja

    2015-01-01

    ABSTRACT BACKGROUND Brain lesions converting to chronic T1 hypointensities (“chronic black holes” [CBH]), indicate severe tissue destruction (axonal loss and irreversible demyelination) in multiple sclerosis (MS). Two mechanisms by which fingolimod could limit MS lesion evolution include sequestration of lymphocytes in the periphery or direct neuroprotective effects. We investigated the effect of fingolimod on the evolution of acute gadolinium‐enhancing (Gd+) brain lesions to CBH in patients with MS. METHODS This was a retrospective nonrandomized comparison of patients with Gd+ brain lesions at the time of starting oral fingolimod [.5 mg/day, n = 26, age (mean ± SD) 39.2 ± 10.6 years, Expanded Disability Status Scale (EDSS) score ‐ median (range): 1.75 (0, 6.5)] to those on no therapy [n = 30, age 41.7 ± 9.3 years; EDSS 1.0 (0, 6)]. Each lesion was classified by whether it converted to a CBH in the year following treatment. RESULTS In the fingolimod group, 99 Gd+ baseline lesions (mean ± SD, range: 3.8 ± 5.1; 1, 21 per patient) were identified of which 25 (25%) evolved to CBH (1.0 ± 2.0; 0, 10 per patient). The untreated group had 62 baseline Gd+ lesions (2.1 ± 2.3; 1, 13), 26 (42%) of which evolved to CBH (.9 ± 1.4; 0, 7) (P = .063). Thirteen patients (50%) receiving fingolimod and 17 untreated patients (57%) developed CBH (P = .79). CONCLUSION This pilot study shows a trend of fingolimod on reducing the conversion rate from acute to chronic destructive MS lesions. Such an effect awaits verification in larger randomized prospective studies. PMID:26445919

  14. [Diagnosis of pediatric multiple sclerosis initially presenting with tumefactive demyelinating lesion using ¹H-magnetic resonance spectroscopy].

    PubMed

    Kageyama, Takashi; Gotoh, Yoko; Sano, Fumie; Katoh, Takeo; Nambu, Mituhiko; Okada, Tsutomu; Suenaga, Toshihiko

    2011-09-01

    We report a case of tumefactive demyelinating lesion (TDL) diagnosed using (1)H-magnetic resonance spectroscopy (¹H-MRS) and conventional magnetic resonance imaging (MRI). A 7-year-old girl was admitted to our hospital with complaints of sleepiness and clumsiness of the right limbs. Neurological examination showed somnolence, right-sided apraxia, and hemiparesis with enhanced tendon reflexes and Babinski sign. Conventional brain MRI revealed extensive hyperintensity in the subcortical white matter of the left frontal lobe in both T₂ weighted and fluid attenuated inversion recovery images. Gadolinium-enhanced T₁ weighted images showed a tumor-like lesion in this area with interrupted rim enhancement, termed open ring sign, and a periventricular lesion along the inferior horn of the right lateral ventricle and a juxtacortical lesion under the right motor cortex. In ¹H-MRS, both single voxel spectroscopy (SVS) and chemical shift imaging showed elevation of choline and reduction of N-acetylaspartate in the left frontal lobe lesion. Furthermore, SVS with a short echo time revealed elevated peaks for glutamate/glutamine complex in this lesion. These results suggested the demyelinating nature of this tumor-like lesion, in accordance with the concept of TDL. Based on this diagnosis, we treated the patient with three sets of methylprednisolone pulse therapy, which resulted in the reduction of TDL and neurological improvement. A follow-up study using MRI also demonstrated two more lesions in the corona radiata and internal capsule of the left hemisphere, supporting a diagnosis of multiple sclerosis based on the revised McDonald's criteria (2010). We concluded that ¹H-MRS may be beneficial in the differential diagnosis of TDL. PMID:21946426

  15. Optimization of PET system design for lesion detection

    SciTech Connect

    Qi, Jinyi

    2000-10-13

    Traditionally, the figures of merit used in designing a PET scanner are spatial resolution, noise equivalent count rate, noise equivalent sensitivity, etc. These measures, however, do not directly reflect the lesion detectability using the PET scanner. Here we propose to optimize PET scanner design directly for lesion detection. The signal-to-noise ratio (SNR) of lesion detection can be easily computed using the theoretical expressions that we have previously derived. Because no time consuming Monte Carlo simulation is needed, the theoretical expressions allow evaluation of a large range of parameters. The PET system parameters can then be chosen to achieve the maximum SNR for lesion detection. The simulation study shown in this paper was focused a single ring PET scanner without depth of interaction measurement. Randoms and scatters were also ignored.

  16. Skin lesion image segmentation using Delaunay Triangulation for melanoma detection.

    PubMed

    Pennisi, Andrea; Bloisi, Domenico D; Nardi, Daniele; Giampetruzzi, Anna Rita; Mondino, Chiara; Facchiano, Antonio

    2016-09-01

    Developing automatic diagnostic tools for the early detection of skin cancer lesions in dermoscopic images can help to reduce melanoma-induced mortality. Image segmentation is a key step in the automated skin lesion diagnosis pipeline. In this paper, a fast and fully-automatic algorithm for skin lesion segmentation in dermoscopic images is presented. Delaunay Triangulation is used to extract a binary mask of the lesion region, without the need of any training stage. A quantitative experimental evaluation has been conducted on a publicly available database, by taking into account six well-known state-of-the-art segmentation methods for comparison. The results of the experimental analysis demonstrate that the proposed approach is highly accurate when dealing with benign lesions, while the segmentation accuracy significantly decreases when melanoma images are processed. This behavior led us to consider geometrical and color features extracted from the binary masks generated by our algorithm for classification, achieving promising results for melanoma detection.

  17. Detection activity assessment and diagnosis of dental caries lesions.

    PubMed

    Braga, Mariana M; Mendes, Fausto M; Ekstrand, Kim R

    2010-07-01

    This article reviews the current methods for detection and assessment of caries lesions focusing on applicability for daily clinical practice. The end point is to arrive at a diagnosis for each caries lesion. Visual inspection aided by a ball-ended probe is essential for caries lesions assessment and the method must be used for all patients. Use of indices, for example, the International Caries Detection and Assessment System (ICDAS), can improve the performance of this method. Using visual inspection, the clinician must decide about the presence, severity and activity of lesions. After this process, additional methods could aid the dentist in reaching a more appropriate treatment decision in some cases. The ICDAS, including the activity assessment system or the Nyvad system, seems to be the best option to reach final diagnoses for managing lesions. The radiographic method is the most recommended additional method available for daily clinical practice.

  18. Skin lesion image segmentation using Delaunay Triangulation for melanoma detection.

    PubMed

    Pennisi, Andrea; Bloisi, Domenico D; Nardi, Daniele; Giampetruzzi, Anna Rita; Mondino, Chiara; Facchiano, Antonio

    2016-09-01

    Developing automatic diagnostic tools for the early detection of skin cancer lesions in dermoscopic images can help to reduce melanoma-induced mortality. Image segmentation is a key step in the automated skin lesion diagnosis pipeline. In this paper, a fast and fully-automatic algorithm for skin lesion segmentation in dermoscopic images is presented. Delaunay Triangulation is used to extract a binary mask of the lesion region, without the need of any training stage. A quantitative experimental evaluation has been conducted on a publicly available database, by taking into account six well-known state-of-the-art segmentation methods for comparison. The results of the experimental analysis demonstrate that the proposed approach is highly accurate when dealing with benign lesions, while the segmentation accuracy significantly decreases when melanoma images are processed. This behavior led us to consider geometrical and color features extracted from the binary masks generated by our algorithm for classification, achieving promising results for melanoma detection. PMID:27215953

  19. Association of Cortical Lesion Burden on 7-T Magnetic Resonance Imaging With Cognition and Disability in Multiple Sclerosis

    PubMed Central

    Harrison, Daniel M.; Roy, Snehashis; Oh, Jiwon; Izbudak, Izlem; Pham, Dzung; Courtney, Susan; Caffo, Brian; Jones, Craig K.; van Zijl, Peter; Calabresi, Peter A.

    2015-01-01

    IMPORTANCE Cortical lesions (CLs) contribute to physical and cognitive disability in multiple sclerosis (MS). Accurate methods for visualization of CLs are necessary for future clinical studies and therapeutic trials in MS. OBJECTIVE To evaluate the clinical relevance of measures of CL burden derived from high-field magnetic resonance imaging (MRI) in MS. DESIGN, SETTING, AND PARTICIPANTS An observational clinical imaging study was conducted at an academic MS center. Participants included 36 individuals with MS (30 relapsing-remitting, 6 secondary or primary progressive) and 15 healthy individuals serving as controls. The study was conducted from March 10, 2010, to November 23, 2012, and analysis was performed from June 1, 2011, to September 30, 2014. Seven-Tesla MRI of the brain was performed with 0.5-mm isotropic resolution magnetization-prepared rapid acquisition gradient echo (MPRAGE) and whole-brain, 3-dimensional, 1.0-mm isotropic resolution magnetization–prepared, fluid-attenuated inversion recovery (MPFLAIR). Cortical lesions, seen as hypointensities on MPRAGE, were manually segmented. Lesions were classified as leukocortical, intracortical, or subpial. Images were segmented using the Lesion-TOADS (Topology-Preserving Anatomical Segmentation) algorithm, and brain structure volumes and white matter (WM) lesion volume were reported. Volumes were normalized to intracranial volume. MAIN OUTCOMES AND MEASURES Physical disability was measured by the Expanded Disability Status Scale (EDSS). Cognitive disability was measured with the Minimal Assessment of Cognitive Function in MS battery. RESULTS Cortical lesions were noted in 35 of 36 participants (97%), with a median of 16 lesions per participant (range, 0-99). Leukocortical lesion volume correlated with WM lesion volume (ρ = 0.50; P = .003) but not with cortical volume; subpial lesion volume inversely correlated with cortical volume (ρ = −0.36; P = .04) but not with WM lesion volume. Total CL count and

  20. Brain tissue volume changes in relapsing-remitting multiple sclerosis: correlation with lesion load.

    PubMed

    Quarantelli, Mario; Ciarmiello, Andrea; Morra, Vincenzo Brescia; Orefice, Giuseppe; Larobina, Michele; Lanzillo, Roberta; Schiavone, Vittorio; Salvatore, Elena; Alfano, Bruno; Brunetti, Arturo

    2003-02-01

    The aim of this study was to simultaneously measure in vivo volumes of gray matter (GM), normal white matter (WM), abnormal white matter (aWM), and cerebro-spinal fluid (CSF), and to assess their relationship in 50 patients with relapsing-remitting multiple sclerosis (RR-MS) (age range, 21-59; mean EDSS, 2.5; mean disease duration, 9.9 years), using an unsupervised multiparametric segmentation procedure applied to brain MR studies. Tissue volumes were normalized to total intracranial volume providing corresponding fractional volumes (fGM, faWM, fWM, and fCSF), subsequently corrected for aWM-related segmentation inaccuracies and adjusted to mean patients' age according to age-related changes measured in 54 normal volunteers (NV) (age range 16-70). In MS patients aWM was 23.8 +/- 29.8 ml (range 0.4-138.8). A significant decrease in fGM was present in MS patients as compared to NV (49.5 +/- 3.2% vs 53.3 +/- 2.1%; P < 0.0001), with a corresponding increase in fCSF (13.0 +/- 3.8% vs 9.1 +/- 2.4%; P < 0.0001). No difference could be detected between the two groups for fWM (37.5 +/- 2.6% vs 37.6 +/- 2.2%). faWM correlated inversely with fGM (R = -0.434, P < 0.001 at regression analysis), and directly with fCSF (R = 0.473, P < 0.001), but not with fWM. There was a significant correlation between disease duration and EDSS, while no relationship was found between EDSS or disease duration and fractional volumes. Brain atrophy in RR-MS is mainly related to GM loss, which correlates with faWM. Both measures do not appear to significantly affect EDSS, which correlates to disease duration. PMID:12595189

  1. Automated Detection of Lupus White Matter Lesions in MRI.

    PubMed

    Roura, Eloy; Sarbu, Nicolae; Oliver, Arnau; Valverde, Sergi; González-Villà, Sandra; Cervera, Ricard; Bargalló, Núria; Lladó, Xavier

    2016-01-01

    Brain magnetic resonance imaging provides detailed information which can be used to detect and segment white matter lesions (WML). In this work we propose an approach to automatically segment WML in Lupus patients by using T1w and fluid-attenuated inversion recovery (FLAIR) images. Lupus WML appear as small focal abnormal tissue observed as hyperintensities in the FLAIR images. The quantification of these WML is a key factor for the stratification of lupus patients and therefore both lesion detection and segmentation play an important role. In our approach, the T1w image is first used to classify the three main tissues of the brain, white matter (WM), gray matter (GM), and cerebrospinal fluid (CSF), while the FLAIR image is then used to detect focal WML as outliers of its GM intensity distribution. A set of post-processing steps based on lesion size, tissue neighborhood, and location are used to refine the lesion candidates. The proposal is evaluated on 20 patients, presenting qualitative, and quantitative results in terms of precision and sensitivity of lesion detection [True Positive Rate (62%) and Positive Prediction Value (80%), respectively] as well as segmentation accuracy [Dice Similarity Coefficient (72%)]. Obtained results illustrate the validity of the approach to automatically detect and segment lupus lesions. Besides, our approach is publicly available as a SPM8/12 toolbox extension with a simple parameter configuration. PMID:27570507

  2. Automated Detection of Lupus White Matter Lesions in MRI

    PubMed Central

    Roura, Eloy; Sarbu, Nicolae; Oliver, Arnau; Valverde, Sergi; González-Villà, Sandra; Cervera, Ricard; Bargalló, Núria; Lladó, Xavier

    2016-01-01

    Brain magnetic resonance imaging provides detailed information which can be used to detect and segment white matter lesions (WML). In this work we propose an approach to automatically segment WML in Lupus patients by using T1w and fluid-attenuated inversion recovery (FLAIR) images. Lupus WML appear as small focal abnormal tissue observed as hyperintensities in the FLAIR images. The quantification of these WML is a key factor for the stratification of lupus patients and therefore both lesion detection and segmentation play an important role. In our approach, the T1w image is first used to classify the three main tissues of the brain, white matter (WM), gray matter (GM), and cerebrospinal fluid (CSF), while the FLAIR image is then used to detect focal WML as outliers of its GM intensity distribution. A set of post-processing steps based on lesion size, tissue neighborhood, and location are used to refine the lesion candidates. The proposal is evaluated on 20 patients, presenting qualitative, and quantitative results in terms of precision and sensitivity of lesion detection [True Positive Rate (62%) and Positive Prediction Value (80%), respectively] as well as segmentation accuracy [Dice Similarity Coefficient (72%)]. Obtained results illustrate the validity of the approach to automatically detect and segment lupus lesions. Besides, our approach is publicly available as a SPM8/12 toolbox extension with a simple parameter configuration. PMID:27570507

  3. Multiple sclerosis. Oligodendrocyte survival and proliferation in an active established lesion.

    PubMed

    Raine, C S; Scheinberg, L; Waltz, J M

    1981-12-01

    Oligodendrocytes have been studied ultrastructurally in relationship to areas of active demyelination in multiple sclerosis. The tissue came from a central nervous system plaque sampled at biopsy during a neurosurgical procedure to correct severe intention tremor in a case of chronic progressive multiple sclerosis. Cells interpreted as oligodendrocytes were abundant within the demyelinated zone, were easily identifiable, and sometimes occurred as nests of cells suggestive of proliferation. Oligodendrocytes were also common within areas of active demyelination where numerous macrophages displayed active phagocytosis of myelin. These oligodendrocytes were paler and perhaps represented residual, surviving cells. In the relatively normal white matter adjacent to the plaque, increased numbers of oligodendrocytes occurred in association with remyelination. In the demyelinated zone, the astrocyte:macrophage:oligodendrocyte ratio was 1:2.25:4.5; within the region of ongoing demyelination, 1:4:4; and in the adjacent white matter, 1:0.1:2.1. On the basis of an apparent proliferation and survival of oligodendrocytes, the findings support the notions that there is no selective depletion of oligodendrocytes either during or shortly following central nervous system demyelination in multiple sclerosis, and that the myelin sheath is the primary target. PMID:7321526

  4. Alpha-B-crystallin induces an immune-regulatory and antiviral microglial response in preactive multiple sclerosis lesions.

    PubMed

    Bsibsi, Malika; Holtman, Inge R; Gerritsen, Wouter H; Eggen, Bart J L; Boddeke, Erik; van der Valk, Paul; van Noort, Johannes M; Amor, Sandra

    2013-10-01

    Microglial nodules are frequently observed in the normal-appearing white matter of multiple sclerosis (MS) patients. Previously, we have shown that these clusters, which we call "preactive MS lesions," are closely associated with stressed oligodendrocytes and myelin sheaths that contain markedly elevated levels of the small stress protein alpha-B-crystallin (HspB5). Here, we show that microglia in these lesions express the recently identified receptors for HspB5, that is, CD14, Toll-like receptor family 1 and 2 (TLR1 and TLR2), and several molecular markers of the microglial response to HspB5. These markers were identified by genome-wide transcript profiling of 12 primary human microglial cultures at 2 time points after exposure to HspB5. These data indicate that HspB5 activates production by microglia of an array of chemokines, immune-regulatory mediators, and a striking number of antiviral genes that are generally inducible by type I interferons. Together, our data suggest that preactive MS lesions are at least in part driven by HspB5 derived from stressed oligodendrocytes and may reflect a local attempt to restore tissue homeostasis.

  5. Automatic colonic lesion detection and tracking in endoscopic videos

    NASA Astrophysics Data System (ADS)

    Li, Wenjing; Gustafsson, Ulf; A-Rahim, Yoursif

    2011-03-01

    The biology of colorectal cancer offers an opportunity for both early detection and prevention. Compared with other imaging modalities, optical colonoscopy is the procedure of choice for simultaneous detection and removal of colonic polyps. Computer assisted screening makes it possible to assist physicians and potentially improve the accuracy of the diagnostic decision during the exam. This paper presents an unsupervised method to detect and track colonic lesions in endoscopic videos. The aim of the lesion screening and tracking is to facilitate detection of polyps and abnormal mucosa in real time as the physician is performing the procedure. For colonic lesion detection, the conventional marker controlled watershed based segmentation is used to segment the colonic lesions, followed by an adaptive ellipse fitting strategy to further validate the shape. For colonic lesion tracking, a mean shift tracker with background modeling is used to track the target region from the detection phase. The approach has been tested on colonoscopy videos acquired during regular colonoscopic procedures and demonstrated promising results.

  6. Reduced cortisol levels in cerebrospinal fluid and differential distribution of 11beta-hydroxysteroid dehydrogenases in multiple sclerosis: implications for lesion pathogenesis.

    PubMed

    Heidbrink, Claudia; Häusler, Sebastian F M; Buttmann, Mathias; Ossadnik, Monika; Strik, Herwig M; Keller, Andreas; Buck, Dorothea; Verbraak, Evert; van Meurs, Marjan; Krockenberger, Mathias; Mehling, Matthias; Mittelbronn, Michel; Laman, Jon D; Wiendl, Heinz; Wischhusen, Jörg

    2010-08-01

    Relapses during multiple sclerosis (MS) are treated by administration of exogenous corticosteroids. However, little is known about the bioavailability of endogenous steroids in the central nervous system (CNS) of MS patients. We thus determined cortisol and dehydroepiandrosterone (DHEA) levels in serum and cerebrospinal fluid (CSF) samples from 34 MS patients, 28 patients with non-inflammatory neurological diseases (NIND) and 16 patients with other inflammatory neurological diseases (OIND). This revealed that MS patients - in sharp contrast to patients with OIND - show normal cortisol concentrations in serum and lowered cortisol levels in the CSF during acute relapses. This local cortisol deficit may relate to poor local activation of cortisone via 11beta-hydroxysteroid dehydrogenase type 1 (11bHSD1) or to inactivation via 11bHSD2. Accordingly, 11bHSD2 was found to be expressed within active plaques, whereas 11bHSD1 was predominantly detected in surrounding "foamy" macrophages. Our study thus provides new insights into the impaired endogenous CNS cortisol regulation in MS patients and its possible relation to MS lesion pathogenesis. Moreover, an observed upregulation of 11bHSD1 in myelin-loaded macrophages in vitro suggests an intriguing hypothesis for the self-limiting nature of MS lesion development. Finally, our findings provide an attractive explanation for the effectivity of high- vs. low-dose exogenous corticosteroids in the therapy of acute relapses.

  7. Detection of dermal systemic sclerosis using noncontact optical coherence elastography

    NASA Astrophysics Data System (ADS)

    Liu, Chih-Hao; Du, Yong; Singh, Manmohan; Li, Jiasong; Wu, Chen; Han, Zhaolong; Raghunathan, Raksha; Hsu, Thomas; Noorani, Shezaan; Hicks, M. John; Mohan, Chandra; Larin, Kirill V.

    2016-03-01

    Systemic sclerosis (SSc) is a connective tissue disease that results in excessive accumulation of collagen in the skin and internal organs. Overall, SSc is a rare disorder, but has a high mortality, particularly in last decade of life. To improve the survival rate, an accurate and early diagnosis is crucial. Currently, the modified Rodnan skin score (mRSS) is the gold standard for evaluating SSc progression based on clinical palpation at 17 sites on the body. However, this procedure can be time consuming, and the assessed score may be biased by the experience of the clinician, causing inter- and intraobserver variabilities. Moreover, the instrinsic elasticity of skin may further bias the mRSS assessment in the early stages of SSc, such as oedematous. To overcome these limitations, there is a need for a rapid, accurate, and objective assessment technique. Optical coherence elastography (OCE) is a novel, rapidly emerging technique, which can assess mechanical contrast in tissues with micrometer spatial resolution. In this work, we demonstrate the first use of OCE to assess the mechanical properties of control and SSc-like diseased skin non-invasively. A focused air-pulse induced an elastic wave in the skin, which was detected by a home-built OCE system. The elastic wave propagated significantly faster in SSc skin compared to healthy skin. The Young's modulus of the SSc skin was significantly higher than that of normal skin (P<0.05). Thus, OCE was able to objectively differentiate healthy and fibrotic skin completely noninvasively and is a promising and potentially useful new technology for quantifying skin involvement in SSc.

  8. Detection of small human cerebral cortical lesions with MRI under different levels of Gaussian smoothing: applications in epilepsy

    NASA Astrophysics Data System (ADS)

    Cantor-Rivera, Diego; Goubran, Maged; Kraguljac, Alan; Bartha, Robert; Peters, Terry

    2010-03-01

    The main objective of this study was to assess the effect of smoothing filter selection in Voxel-Based Morphometry studies on structural T1-weighted magnetic resonance images. Gaussian filters of 4 mm, 8 mm or 10 mm Full Width at High Maximum are commonly used, based on the assumption that the filter size should be at least twice the voxel size to obtain robust statistical results. The hypothesis of the presented work was that the selection of the smoothing filter influenced the detectability of small lesions in the brain. Mesial Temporal Sclerosis associated to Epilepsy was used as the case to demonstrate this effect. Twenty T1-weighted MRIs from the BrainWeb database were selected. A small phantom lesion was placed in the amygdala, hippocampus, or parahippocampal gyrus of ten of the images. Subsequently the images were registered to the ICBM/MNI space. After grey matter segmentation, a T-test was carried out to compare each image containing a phantom lesion with the rest of the images in the set. For each lesion the T-test was repeated with different Gaussian filter sizes. Voxel-Based Morphometry detected some of the phantom lesions. Of the three parameters considered: location,size, and intensity; it was shown that location is the dominant factor for the detection of the lesions.

  9. Infrared spectroscopic characterization of human white matter, grey matter, and multiple sclerosis lesions

    NASA Astrophysics Data System (ADS)

    Choo, Lin-P'ing; Jackson, Michael; Halliday, William C.; Mantsch, Henry H.

    1994-01-01

    FT-IR spectroscopy has been used to characterize white matter, grey matter, and multiple sclerosis (MS) plaques from human central nervous system (CNS) tissue. Discrimination among these three tissue types is possible due to variations in composition. Spectra of white matter exhibit strong lipid absorptions. In contrast, spectra of grey matter reveal a reduced lipid contribution and a significant absorption from water. MS plaques exhibit spectra indicative of lipid loss and, depending upon whether the plaques are chronic or acute, changes in the protein and/or water content.

  10. Detecting Proximal Secondary Caries Lesions: A Cost-effectiveness Analysis.

    PubMed

    Schwendicke, F; Brouwer, F; Paris, S; Stolpe, M

    2016-02-01

    When choosing detection methods for secondary caries lesions, dentists need to weigh sensitivity, allowing early initiation of retreatments to avoid lesion progression, against specificity, aiming to reduce risks of false-positive diagnoses and invasive overtreatments. We assessed the cost-effectiveness of different detection methods for proximal secondary lesions using Monte Carlo microsimulations. A vital permanent molar with an occlusal-proximal restoration was simulated over the lifetime of an initially 20-y-old. Three methods were compared: biannual tactile detection, radiographic detection every 2 y, and biannual laser fluorescence detection. Methods were employed either on their own or in pairwise combinations at sensitive and specific thresholds estimated with systematically collected data. A mixed public-private payer perspective in the context of German health care was applied. Effectiveness was calculated as years of tooth retention. Net-benefit analyses were used to evaluate cost-effectiveness acceptability at different willingness-to-pay thresholds. Radiographic detection verified by tactile assessment (both at specific thresholds) was least costly (mean, 1,060 euros) but had limited effectiveness (mean retention time, 50 y). The most effective but also more costly combination was laser fluorescence detection verified by radiography, again at specific thresholds (1157 euros, 53 y, acceptable if willingness to pay >32 euro/y). In the majority of simulations, not combining detection methods or applying them at sensitive thresholds was less effective and more costly. Net benefits were not greatly altered by applying different discounting rates or using different baseline prevalence of secondary lesions. Current detection methods for secondary lesions should best be used in combination, not on their own, at specific thresholds to avoid false-positive diagnoses leading to costly and invasive overtreatment. The relevant characteristics, such as predictive

  11. Red lesion detection using background estimation and lesions characteristics in diabetic retinal image

    NASA Astrophysics Data System (ADS)

    Zhang, Dongbo; Peng, Yinghui; Yi, Yao; Shang, Xingyu

    2013-10-01

    Detection of red lesions [hemorrhages (HRs) and microaneurysms (MAs)] is crucial for the diagnosis of early diabetic retinopathy. A method based on background estimation and adapted to specific characteristics of HRs and MAs is proposed. Candidate red lesions are located by background estimation and Mahalanobis distance measure and then some adaptive postprocessing techniques, which include vessel detection, nonvessel exclusion based on shape analysis, and noise points exclusion by double-ring filter (only used for MAs detection), are conducted to remove nonlesion pixels. The method is evaluated on our collected image dataset, and experimental results show that it is better than or approximate to other previous approaches. It is effective to reduce the false-positive and false-negative results that arise from incomplete and inaccurate vessel structure.

  12. More Severe Extratemporal Damages in Mesial Temporal Lobe Epilepsy With Hippocampal Sclerosis Than That With Other Lesions

    PubMed Central

    Wei, Wei; Zhang, Zhiqiang; Xu, Qiang; Yang, Fang; Sun, Kangjian; Lu, Guangming

    2016-01-01

    Abstract Mesial temporal lobe epilepsy with hippocampal sclerosis (mTLE-HS) presents different clinical presentations from that with other lesions (OL). It is significant to investigate the neural mechanism underlying the different clinical presentations using neuroimaging study. Thirty mTLE patients with mTLE-HS, 30 mTLE patients with other lesions (mTLE-OL), and 30 age- and sex-matched healthy controls were involved. Amplitude of low-frequency fluctuation (ALFF) analysis-based resting-state functional magnetic resonance imaging (fMRI) and voxel-based morphometry (VBM) based morphometric MRI were employed to describing functional and structural imaging alterations in mTLE. Imaging parameters of ALFF and gray matter volume (GMV) were compared among groups and correlated with clinical variables and cognitive scores. For parameter of ALFF, both patient groups of mTLE-HS and mTLE-OL showed decrease in the frontal cortices relative to the healthy controls; mTLE-HS showed more decrease in the prefrontal and brain default regions relative to mTLE-OL. For GMV, both patient groups showed decrease in the frontal cortex, thalamus, and cerebellum; mTLE-HS showed more GMV decrease relative to the mTLE-OL, also mainly in the prefrontal and brain default regions. In both patient groups, the prefrontal regions showed negative correlation between GMV and epilepsy duration. This work revealed distinct alteration patterns of functional and structural brain organizations in mTLEs with different forms. MTLE-HS, despite with smaller lesion size of the pathological focus, presented more severe functional and structural damages in the extratemporal regions than mTLE-OL. The findings provided imaging evidence to support the proposal that mTLE-HS is a special epilepsy syndrome. PMID:26962820

  13. The impact of mammographic density and lesion location on detection

    NASA Astrophysics Data System (ADS)

    Al Mousa, Dana; Ryan, Elaine; Lee, Warwick; Nickson, Carolyn; Pietrzyk, Mariusz; Reed, Warren; Poulos, Ann; Li, Yanpeng; Brennan, Patrick

    2013-03-01

    The aim of this study is to examine the impact of breast density and lesion location on detection. A set of 55 mammographic images (23 abnormal images with 26 lesions and 32 normal images) were examined by 22 expert radiologists. The images were classified by an expert radiologist according to the Synoptic Breast Imaging Report of the National Breast Cancer Centre (NBCC) as having low mammographic density (D1<25% glandular and D2> 25-50% glandular) or high density (D3 51-75% glandular and D4> 75-glandular). The observers freely examined the images and located any malignancy using a 5-point confidence. Performance was defined using the following metrics: sensitivity, location sensitivity, specificity, receiver operating characteristic (ROC Az) curves and jackknife free-response receiver operator characteristics (JAFROC) figures of merit. Significant increases in sensitivity (p= 0.0174) and ROC (p=0.0001) values were noted for the higher density compared with lower density images according to NBCC classification. No differences were seen in radiologists' performance between lesions within or outside the fibroglandular region. In conclusion, analysis of our data suggests that radiologists scored higher using traditional metrics in higher mammographic density images without any improvement in lesion localisation. Lesion location whether within or outside the fibroglandular region appeared to have no impact on detection abilities suggesting that if a masking effect is present the impact is minimal. Eye-tracking analyses are ongoing.

  14. Lung lesions: correlation between viewing time and detection.

    PubMed

    Oestmann, J W; Greene, R; Kushner, D C; Bourgouin, P M; Linetsky, L; Llewellyn, H J

    1988-02-01

    The influence of viewing time on the detectability of subtle and obvious lung cancers was studied. Frontal chest radiographs of 40 patients with subtle cancers, 40 patients with obvious cancers, and 40 healthy control subjects were shown to four observers for four different viewing times (0.25 second, 1 second, 4 seconds, and unlimited time). Receiver operating characteristic analysis was used to compare the detectability of lesions. Performance was degraded as viewing time decreased. The true-positive fractions for subtle and obvious cancers were 30% and 70% at 0.25 second and 74% and 98% at unlimited viewing time, respectively, for a given false-positive fraction of 20%. Thus, even with unlimited viewing time, the false-negative fraction for subtle cancers was 26%. The difference in detectability between subtle and obvious lung cancers was exaggerated at 1.0 second compared with 4 seconds and unlimited viewing time. The following conclusions were reached: (a) a substantial proportion of subtle lung lesions are missed, even with unlimited viewing time; (b) a large proportion of obvious lung cancers are detected with flash viewing; (c) the detectability of lesions decreases considerably as viewing time becomes less than 4 seconds; and (d) differences in detectability are exaggerated by short viewing times. PMID:3336720

  15. Large focal tumor-like demyelinating lesions of the brain: intermediate entity between multiple sclerosis and acute disseminated encephalomyelitis? A study of 31 patients.

    PubMed

    Kepes, J J

    1993-01-01

    Thirty-one patients with large, focal cerebral demyelinating lesions are reported. Twenty-four patients had solitary lesions and 7 had multiple foci, the latter apparently of identical age. The lesions presented clinically and radiologically as brain tumors (gliomas or metastases) or as multiple cysts. Six patients were older than 57 years (2 in their 70s) at the onset of their symptoms. The demyelinating nature of the lesions was established through biopsy in each patient and all improved significantly after corticosteroid therapy. Three patients developed additional lesions during the follow-up periods ranging from 9 months to 12 years consistent with the course of multiple sclerosis. Twenty-eight patients did not develop additional lesions. These included 6 patients with multiple lesions at the onset. In 1 of the patients, the first symptoms developed 10 days after receiving vaccination against influenza. Two patients had concomitant malignancy (chronic monomyelogenous leukemia and retroperitoneal seminoma respectively) and 1 patient developed immunoblastic sarcoma in the opposite hemisphere after biopsy diagnosis and steroid treatment of her demyelinating lesion. Tumor-like masses of demyelination may occupy an intermediate position between multiple sclerosis and postinfectious/postvaccination encephalitis. The clinical course (history of vaccination in one instance, acute onset, good response to corticosteroids, no clinical or radiological evidence of new lesions in the great majority of patients) favored postinfectious/postvaccination encephalitis. Lesion size however greatly exceeded that of the small foci of perivenous demyelination seen in typical postinfectious/postvaccination encephalitis and tended to present as space-occupying masses.

  16. Multiparametric MRI for Localized Prostate Cancer: Lesion Detection and Staging

    PubMed Central

    Margolis, Daniel J. A.

    2014-01-01

    Multiparametric MRI of the prostate combines high-resolution anatomic imaging with functional imaging of alterations in normal tissue caused by neoplastic transformation for the identification and characterization of in situ prostate cancer. Lesion detection relies on a systematic approach to the analysis of both anatomic and functional imaging using established criteria for the delineation of suspicious areas. Staging includes visual and functional analysis of the prostate “capsule” to determine if in situ disease is, in fact, organ-confined, as well as the evaluation of pelvic structures including lymph nodes and bones for the detection of metastasis. Although intertwined, the protocol can be optimized depending on whether lesion detection or staging is of the highest priority. PMID:25525600

  17. ADvanced IMage Algebra (ADIMA): a novel method for depicting multiple sclerosis lesion heterogeneity, as demonstrated by quantitative MRI

    PubMed Central

    Tozer, Daniel J; Schmierer, Klaus; Chard, Declan T; Anderson, Valerie M; Altmann, Daniel R; Miller, David H; Wheeler-Kingshott, Claudia AM

    2013-01-01

    Background: There are modest correlations between multiple sclerosis (MS) disability and white matter lesion (WML) volumes, as measured by T2-weighted (T2w) magnetic resonance imaging (MRI) scans (T2-WML). This may partly reflect pathological heterogeneity in WMLs, which is not apparent on T2w scans. Objective: To determine if ADvanced IMage Algebra (ADIMA), a novel MRI post-processing method, can reveal WML heterogeneity from proton-density weighted (PDw) and T2w images. Methods: We obtained conventional PDw and T2w images from 10 patients with relapsing–remitting MS (RRMS) and ADIMA images were calculated from these. We classified all WML into bright (ADIMA-b) and dark (ADIMA-d) sub-regions, which were segmented. We obtained conventional T2-WML and T1-WML volumes for comparison, as well as the following quantitative magnetic resonance parameters: magnetisation transfer ratio (MTR), T1 and T2. Also, we assessed the reproducibility of the segmentation for ADIMA-b, ADIMA-d and T2-WML. Results: Our study’s ADIMA-derived volumes correlated with conventional lesion volumes (p < 0.05). ADIMA-b exhibited higher T1 and T2, and lower MTR than the T2-WML (p < 0.001). Despite the similarity in T1 values between ADIMA-b and T1-WML, these regions were only partly overlapping with each other. ADIMA-d exhibited quantitative characteristics similar to T2-WML; however, they were only partly overlapping. Mean intra- and inter-observer coefficients of variation for ADIMA-b, ADIMA-d and T2-WML volumes were all < 6 % and < 10 %, respectively. Conclusion: ADIMA enabled the simple classification of WML into two groups having different quantitative magnetic resonance properties, which can be reproducibly distinguished. PMID:23037551

  18. Knowledge-based 3D segmentation of the brain in MR images for quantitative multiple sclerosis lesion tracking

    NASA Astrophysics Data System (ADS)

    Fisher, Elizabeth; Cothren, Robert M., Jr.; Tkach, Jean A.; Masaryk, Thomas J.; Cornhill, J. Fredrick

    1997-04-01

    Brain segmentation in magnetic resonance (MR) images is an important step in quantitative analysis applications, including the characterization of multiple sclerosis (MS) lesions over time. Our approach is based on a priori knowledge of the intensity and three-dimensional (3D) spatial relationships of structures in MR images of the head. Optimal thresholding and connected-components analysis are used to generate a starting point for segmentation. A 3D radial search is then performed to locate probable locations of the intra-cranial cavity (ICC). Missing portions of the ICC surface are interpolated in order to exclude connected structures. Partial volume effects and inter-slice intensity variations in the image are accounted for automatically. Several studies were conducted to validate the segmentation. Accuracy was tested by calculating the segmented volume and comparing to known volumes of a standard MR phantom. Reliability was tested by comparing calculated volumes of individual segmentation results from multiple images of the same subject. The segmentation results were also compared to manual tracings. The average error in volume measurements for the phantom was 1.5% and the average coefficient of variation of brain volume measurements of the same subject was 1.2%. Since the new algorithm requires minimal user interaction, variability introduced by manual tracing and interactive threshold or region selection was eliminated. Overall, the new algorithm was shown to produce a more accurate and reliable brain segmentation than existing manual and semi-automated techniques.

  19. Automatic detection of ureter lesions in CT urography

    NASA Astrophysics Data System (ADS)

    Exell, Trevor; Hadjiiski, Lubomir; Chan, Heang-Ping; Cha, Kenny H.; Caoili, Elaine M.; Cohan, Richard H.; Wei, Jun; Zhou, Chuan

    2016-03-01

    We are developing a CAD system for automated detection of ureter abnormalities in multi-detector row CT urography (CTU). Our CAD system consists of two stages. The first stage automatically tracks the ureter via the previously proposed COmbined Model-guided Path-finding Analysis and Segmentation System (COMPASS). The second stage consists of lesion enhancement filtering, adaptive thresholding, edge extraction, and noise removal. With IRB approval, 36 cases were collected from patient files, including 15 cases (17 ureters with 32 lesions) for training, and 10 abnormal cases (11 ureters with 17 lesions) and 11 normal cases (22 ureters) for testing. All lesions were identified by experienced radiologists on the CTU images and COMPASS was able to track the ureters in 100% of the cases. The average lesion size was 5.1 mm (range: 2.1 mm - 21.9 mm) for the training set and 6.1 mm (range: 2.0 mm - 18.9 mm) for the test set. The average conspicuity was 4.1 (range: 2 to 5) and 3.9 (range: 1 to 5) on a scale of 1 to 5 (5 very subtle), for the training and test sets, respectively. The system achieved 90.6% sensitivity at 2.41 (41/17) FPs/ureter for the training set and 70.6% sensitivity at 2 (44/22) FPs/normal ureter for the test set. These initial results demonstrate the feasibility of the CAD system to track the ureter and detect ureter cancer of medium conspicuity and relatively small sizes.

  20. System for the comprehensive analysis of multiple sclerosis lesion load based on MR imagery

    NASA Astrophysics Data System (ADS)

    Udupa, Jayaram K.; Wei, Luogang; Miki, Yukio; Grossman, Robert I.

    1997-05-01

    The system is based on the premise that, in the two related tasks required for object definition, namely object recognition and delineation, human operators usually outperform computer algorithms in recognition and it is vice versa for delineation. In our system, some global recognition help is therefore taken from operators, while delineation is done automatically using fuzzy topological algorithms. The lesion quantification methods for the various protocols differ somewhat but follow this general framework. All objects are extracted as 3D fuzzy connected objects. For combining inter- and intra-protocol longitudinal information, fuzzy object registration algorithms are developed and incorporated into the system. A variety of validation studies have been conducted for all protocols to test inter- and intra-operator variations, repeat scan variations, and accuracy in terms of false positive and false negative volume fractions. They all indicate a value of less than 1.5 percent for these factors. THe operator time taken per 3D study varies between 1-20 minutes.

  1. Improved Detection of Microsatellite Instability in Early Colorectal Lesions

    PubMed Central

    Albrecht, Dawn M.; Grimes, Ian C.; Weiss, Jennifer M.; Matkowskyj, Kristina A.; Agni, Rashmi M.; Vyazunova, Irina; Clipson, Linda; Storts, Douglas R.; Thliveris, Andrew T.; Halberg, Richard B.

    2015-01-01

    Microsatellite instability (MSI) occurs in over 90% of Lynch syndrome cancers and is considered a hallmark of the disease. MSI is an early event in colon tumor development, but screening polyps for MSI remains controversial because of reduced sensitivity compared to more advanced neoplasms. To increase sensitivity, we investigated the use of a novel type of marker consisting of long mononucleotide repeat (LMR) tracts. Adenomas from 160 patients, ranging in age from 29–55 years old, were screened for MSI using the new markers and compared with current marker panels and immunohistochemistry standards. Overall, 15 tumors were scored as MSI-High using the LMRs compared to 9 for the NCI panel and 8 for the MSI Analysis System (Promega). This difference represents at least a 1.7-fold increase in detection of MSI-High lesions over currently available markers. Moreover, the number of MSI-positive markers per sample and the size of allelic changes were significantly greater with the LMRs (p = 0.001), which increased confidence in MSI classification. The overall sensitivity and specificity of the LMR panel for detection of mismatch repair deficient lesions were 100% and 96%, respectively. In comparison, the sensitivity and specificity of the MSI Analysis System were 67% and 100%; and for the NCI panel, 75% and 97%. The difference in sensitivity between the LMR panel and the other panels was statistically significant (p<0.001). The increased sensitivity for detection of MSI-High phenotype in early colorectal lesions with the new LMR markers indicates that MSI screening for the early detection of Lynch syndrome might be feasible. PMID:26252492

  2. Human Brain Atlas-based Multimodal MRI Analysis of Volumetry, Diffusimetry, Relaxometry and Lesion Distribution in Multiple Sclerosis Patients and Healthy Adult Controls: Implications for understanding the Pathogenesis of Multiple Sclerosis and Consolidation of Quantitative MRI Results in MS

    PubMed Central

    Hasan, Khader M.; Walimuni, Indika S.; Abid, Humaira; Datta, Sushmita; Wolinsky, Jerry S.; Narayana, Ponnada A.

    2011-01-01

    Multiple sclerosis (MS) is the most common immune-mediated disabling neurological disease of the central nervous system. The pathogenesis of MS is not fully understood. Histopathology implicates both demyelination and axonal degeneration as the major contributors to the accumulation of disability. The application of several in vivo quantitative magnetic resonance imaging (MRI) methods to both lesioned and normal-appearing brain tissue has not yet provided a solid conclusive support of the hypothesis that MS might be a diffuse disease. In this work, we adopted FreeSurfer to provide standardized macrostructure or volumetry of lesion free normal-appearing brain tissue in combination with multiple quantitative MRI metrics (T2 relaxation time, diffusion tensor anisotropy and diffusivities) that characterize tissue microstructural integrity. By incorporating a large number of healthy controls, we have attempted to separate the natural age-related change from the disease-induced effects. Our work shows elevation in diffusivity and relaxation times and reduction in volume in a number of normal-appearing white matter and gray matter structures in relapsing-remitting multiple sclerosis patients. These changes were related in part with the spatial distribution of lesions. The whole brain lesion load and age-adjusted expanded disability status score showed strongest correlations in regions such as corpus callosum with qMRI metrics that are believed to be specific markers of axonal dysfunction, consistent with histologic data of others indicating axonal loss that is independent of focal lesions. Our results support that MS at least in part has a neurodegenerative component. PMID:21978603

  3. Detection of Lesions Underlying Intractable Epilepsy on T1-Weighted MRI as an Outlier Detection Problem

    PubMed Central

    El Azami, Meriem; Hammers, Alexander; Jung, Julien; Costes, Nicolas; Bouet, Romain; Lartizien, Carole

    2016-01-01

    Pattern recognition methods, such as computer aided diagnosis (CAD) systems, can help clinicians in their diagnosis by marking abnormal regions in an image. We propose a machine learning system based on a one-class support vector machine (OC-SVM) classifier for the detection of abnormalities in magnetic resonance images (MRI) applied to patients with intractable epilepsy. The system learns the features associated with healthy control subjects, allowing a voxelwise assessment of the deviation of a test subject pattern from the learned patterns. While any number of various features can be chosen and learned, here we focus on two texture parameters capturing image patterns associated with epileptogenic lesions on T1-weighted brain MRI e.g. heterotopia and blurred junction between the grey and white matter. The CAD output consists of patient specific 3D maps locating clusters of suspicious voxels ranked by size and degree of deviation from control patterns. System performance was evaluated using realistic simulations of challenging detection tasks as well as clinical data of 77 healthy control subjects and of eleven patients (13 lesions). It was compared to that of a mass univariate statistical parametric mapping (SPM) single subject analysis based on the same set of features. For all simulations, OC-SVM yielded significantly higher values of the area under the ROC curve (AUC) and higher sensitivity at low false positive rate. For the clinical data, both OC-SVM and SPM successfully detected 100% of the lesions in the MRI positive cases (3/13). For the MRI negative cases (10/13), OC-SVM detected 7/10 lesions and SPM analysis detected 5/10 lesions. In all experiments, OC-SVM produced fewer false positive detections than SPM. OC-SVM may be a versatile system for unbiased lesion detection. PMID:27603778

  4. Detection of Lesions Underlying Intractable Epilepsy on T1-Weighted MRI as an Outlier Detection Problem.

    PubMed

    El Azami, Meriem; Hammers, Alexander; Jung, Julien; Costes, Nicolas; Bouet, Romain; Lartizien, Carole

    2016-01-01

    Pattern recognition methods, such as computer aided diagnosis (CAD) systems, can help clinicians in their diagnosis by marking abnormal regions in an image. We propose a machine learning system based on a one-class support vector machine (OC-SVM) classifier for the detection of abnormalities in magnetic resonance images (MRI) applied to patients with intractable epilepsy. The system learns the features associated with healthy control subjects, allowing a voxelwise assessment of the deviation of a test subject pattern from the learned patterns. While any number of various features can be chosen and learned, here we focus on two texture parameters capturing image patterns associated with epileptogenic lesions on T1-weighted brain MRI e.g. heterotopia and blurred junction between the grey and white matter. The CAD output consists of patient specific 3D maps locating clusters of suspicious voxels ranked by size and degree of deviation from control patterns. System performance was evaluated using realistic simulations of challenging detection tasks as well as clinical data of 77 healthy control subjects and of eleven patients (13 lesions). It was compared to that of a mass univariate statistical parametric mapping (SPM) single subject analysis based on the same set of features. For all simulations, OC-SVM yielded significantly higher values of the area under the ROC curve (AUC) and higher sensitivity at low false positive rate. For the clinical data, both OC-SVM and SPM successfully detected 100% of the lesions in the MRI positive cases (3/13). For the MRI negative cases (10/13), OC-SVM detected 7/10 lesions and SPM analysis detected 5/10 lesions. In all experiments, OC-SVM produced fewer false positive detections than SPM. OC-SVM may be a versatile system for unbiased lesion detection. PMID:27603778

  5. Accuracy for detection of simulated lesions: comparison of fluid-attenuated inversion-recovery, proton density--weighted, and T2-weighted synthetic brain MR imaging

    NASA Technical Reports Server (NTRS)

    Herskovits, E. H.; Itoh, R.; Melhem, E. R.

    2001-01-01

    OBJECTIVE: The objective of our study was to determine the effects of MR sequence (fluid-attenuated inversion-recovery [FLAIR], proton density--weighted, and T2-weighted) and of lesion location on sensitivity and specificity of lesion detection. MATERIALS AND METHODS: We generated FLAIR, proton density-weighted, and T2-weighted brain images with 3-mm lesions using published parameters for acute multiple sclerosis plaques. Each image contained from zero to five lesions that were distributed among cortical-subcortical, periventricular, and deep white matter regions; on either side; and anterior or posterior in position. We presented images of 540 lesions, distributed among 2592 image regions, to six neuroradiologists. We constructed a contingency table for image regions with lesions and another for image regions without lesions (normal). Each table included the following: the reviewer's number (1--6); the MR sequence; the side, position, and region of the lesion; and the reviewer's response (lesion present or absent [normal]). We performed chi-square and log-linear analyses. RESULTS: The FLAIR sequence yielded the highest true-positive rates (p < 0.001) and the highest true-negative rates (p < 0.001). Regions also differed in reviewers' true-positive rates (p < 0.001) and true-negative rates (p = 0.002). The true-positive rate model generated by log-linear analysis contained an additional sequence-location interaction. The true-negative rate model generated by log-linear analysis confirmed these associations, but no higher order interactions were added. CONCLUSION: We developed software with which we can generate brain images of a wide range of pulse sequences and that allows us to specify the location, size, shape, and intrinsic characteristics of simulated lesions. We found that the use of FLAIR sequences increases detection accuracy for cortical-subcortical and periventricular lesions over that associated with proton density- and T2-weighted sequences.

  6. Example based lesion segmentation

    NASA Astrophysics Data System (ADS)

    Roy, Snehashis; He, Qing; Carass, Aaron; Jog, Amod; Cuzzocreo, Jennifer L.; Reich, Daniel S.; Prince, Jerry; Pham, Dzung

    2014-03-01

    Automatic and accurate detection of white matter lesions is a significant step toward understanding the progression of many diseases, like Alzheimer's disease or multiple sclerosis. Multi-modal MR images are often used to segment T2 white matter lesions that can represent regions of demyelination or ischemia. Some automated lesion segmentation methods describe the lesion intensities using generative models, and then classify the lesions with some combination of heuristics and cost minimization. In contrast, we propose a patch-based method, in which lesions are found using examples from an atlas containing multi-modal MR images and corresponding manual delineations of lesions. Patches from subject MR images are matched to patches from the atlas and lesion memberships are found based on patch similarity weights. We experiment on 43 subjects with MS, whose scans show various levels of lesion-load. We demonstrate significant improvement in Dice coefficient and total lesion volume compared to a state of the art model-based lesion segmentation method, indicating more accurate delineation of lesions.

  7. Example Based Lesion Segmentation

    PubMed Central

    Roy, Snehashis; He, Qing; Carass, Aaron; Jog, Amod; Cuzzocreo, Jennifer L.; Reich, Daniel S.; Prince, Jerry; Pham, Dzung

    2016-01-01

    Automatic and accurate detection of white matter lesions is a significant step toward understanding the progression of many diseases, like Alzheimer’s disease or multiple sclerosis. Multi-modal MR images are often used to segment T2 white matter lesions that can represent regions of demyelination or ischemia. Some automated lesion segmentation methods describe the lesion intensities using generative models, and then classify the lesions with some combination of heuristics and cost minimization. In contrast, we propose a patch-based method, in which lesions are found using examples from an atlas containing multi-modal MR images and corresponding manual delineations of lesions. Patches from subject MR images are matched to patches from the atlas and lesion memberships are found based on patch similarity weights. We experiment on 43 subjects with MS, whose scans show various levels of lesion-load. We demonstrate significant improvement in Dice coefficient and total lesion volume compared to a state of the art model-based lesion segmentation method, indicating more accurate delineation of lesions.

  8. Regularization design in penalized maximum-likelihood image reconstruction for lesion detection in 3D PET

    NASA Astrophysics Data System (ADS)

    Yang, Li; Zhou, Jian; Ferrero, Andrea; Badawi, Ramsey D.; Qi, Jinyi

    2014-01-01

    Detecting cancerous lesions is a major clinical application in emission tomography. In previous work, we have studied penalized maximum-likelihood (PML) image reconstruction for the detection task and proposed a method to design a shift-invariant quadratic penalty function to maximize detectability of a lesion at a known location in a two dimensional image. Here we extend the regularization design to maximize detectability of lesions at unknown locations in fully 3D PET. We used a multiview channelized Hotelling observer (mvCHO) to assess the lesion detectability in 3D images to mimic the condition where a human observer examines three orthogonal views of a 3D image for lesion detection. We derived simplified theoretical expressions that allow fast prediction of the detectability of a 3D lesion. The theoretical results were used to design the regularization in PML reconstruction to improve lesion detectability. We conducted computer-based Monte Carlo simulations to compare the optimized penalty with the conventional penalty for detecting lesions of various sizes. Only true coincidence events were simulated. Lesion detectability was also assessed by two human observers, whose performances agree well with that of the mvCHO. Both the numerical observer and human observer results showed a statistically significant improvement in lesion detection by using the proposed penalty function compared to using the conventional penalty function.

  9. Fusing Markov random fields with anatomical knowledge and shape-based analysis to segment multiple sclerosis white matter lesions in magnetic resonance images of the brain

    NASA Astrophysics Data System (ADS)

    AlZubi, Stephan; Toennies, Klaus D.; Bodammer, N.; Hinrichs, Herman

    2002-05-01

    This paper proposes an image analysis system to segment multiple sclerosis lesions of magnetic resonance (MR) brain volumes consisting of 3 mm thick slices using three channels (images showing T1-, T2- and PD -weighted contrast). The method uses the statistical model of Markov Random Fields (MRF) both at low and high levels. The neighborhood system used in this MRF is defined in three types: (1) Voxel to voxel: a low-level heterogeneous neighborhood system is used to restore noisy images. (2) Voxel to segment: a fuzzy atlas, which indicates the probability distribution of each tissue type in the brain, is registered elastically with the MRF. It is used by the MRF as a-priori knowledge to correct miss-classified voxels. (3) Segment to segment: Remaining lesion candidates are processed by a feature based classifier that looks at unary and neighborhood information to eliminate more false positives. An expert's manual segmentation was compared with the algorithm.

  10. Label-free method for anti-glucopeptide antibody detection in Multiple Sclerosis

    PubMed Central

    Real-Fernández, Feliciana; Rossi, Giada; Lolli, Francesco; Papini, Anna Maria; Rovero, Paolo

    2015-01-01

    Surface plasmon resonance technique is particularly interesting in immunology because it has the potential to visualize label-free antigen-antibody interactions in real-time, thus enabling antibody detection and monitoring. Herein we release the guidelines for the correct use of a method to detect specific antibodies directly in Multiple Sclerosis patients’ sera using a glucopeptide-based label-free biosensor. The protocol describes the strategy employed for the immobilization of glucopeptide antigen onto a gold sensor chip and the evaluation of the specific binding of serum antibodies to the immobilized antigen. • Label-free method for the real time screening of disease-specific antibodies within a few minutes; • The described protocol employs small quantities of glucopeptide antigen and blood serum samples saving method-cost; • Stability of the immobilized glucopeptide antigen guarantees the regeneration of the surface allowing re-use the immunosensor with high automated throughput. The antibodies detected using the described methodology can be evaluated as biomarkers of Multiple Sclerosis. The SPR detection system is able to characterize antibodies significantly different from those evaluated in the classical enzyme-linked immunosorbent assays (ELISA). PMID:26150982

  11. Label-free method for anti-glucopeptide antibody detection in Multiple Sclerosis.

    PubMed

    Real-Fernández, Feliciana; Rossi, Giada; Lolli, Francesco; Papini, Anna Maria; Rovero, Paolo

    2015-01-01

    Surface plasmon resonance technique is particularly interesting in immunology because it has the potential to visualize label-free antigen-antibody interactions in real-time, thus enabling antibody detection and monitoring. Herein we release the guidelines for the correct use of a method to detect specific antibodies directly in Multiple Sclerosis patients' sera using a glucopeptide-based label-free biosensor. The protocol describes the strategy employed for the immobilization of glucopeptide antigen onto a gold sensor chip and the evaluation of the specific binding of serum antibodies to the immobilized antigen. •Label-free method for the real time screening of disease-specific antibodies within a few minutes;•The described protocol employs small quantities of glucopeptide antigen and blood serum samples saving method-cost;•Stability of the immobilized glucopeptide antigen guarantees the regeneration of the surface allowing re-use the immunosensor with high automated throughput. The antibodies detected using the described methodology can be evaluated as biomarkers of Multiple Sclerosis. The SPR detection system is able to characterize antibodies significantly different from those evaluated in the classical enzyme-linked immunosorbent assays (ELISA). PMID:26150982

  12. Polarized hyperspectral imaging system for in vivo detection of vulvar lichen sclerosis

    NASA Astrophysics Data System (ADS)

    Qu, Yingjie; Ren, Wenqi; Liu, Songde; Liu, Peng; Xie, Lan; Zhang, Xiaoyuan; Zhang, Shiwu; Chang, Shufang; Xu, Ronald

    2016-03-01

    Vulvar lichen sclerosis (VLS) is a chronic, inflammatory and mucocutaneous disease of extragenital skin, which often goes undetected for years. The underlying causes are associated with the decrease of VEGF that reduces the blood oxygenation of vulva and the structural changes in the collagen fibrils, which can lead to scarring of the affected area. However, few methods are available for quantitative detection of VLS. Clinician's examinations are subjective and may lead to misdiagnosis. Spectroscopy is a potentially effective method for noninvasive detection of VLS. In this paper, we developed a polarized, hyperspectral imaging system for quantitative assessment. The system utilized a hyperspectral camera to collect the reflectance images of the entire vulva under Xenon lamp illumination with and without a polarizer in front of the fiber. One image (Ipar) acquired with the AOTF parallel to the polarization of illumination and the other image (Iper) acquired with the AOTF perpendicular to the illumination. This paper compares polarized images of VLS in a pilot clinical study. The collected reflectance data under Xenon lamp illumination without a polarizer are calibrated and the hyperspectral signals are extracted. An IRB approved clinical trial was carried out to evaluate the clinical utility for VLS detection. Our pilot study has demonstrated the technical potential of using this polarized hyperspectral imaging system for in vivo detection of vulvar lichen sclerosis.

  13. Detection of ectopic B-cell follicles with germinal centers in the meninges of patients with secondary progressive multiple sclerosis.

    PubMed

    Serafini, Barbara; Rosicarelli, Barbara; Magliozzi, Roberta; Stigliano, Egidio; Aloisi, Francesca

    2004-04-01

    Multiple sclerosis (MS) is characterized by synthesis of oligoclonal immunoglobulins and the presence of B-cell clonal expansions in the central nervous system (CNS). Because ectopic lymphoid tissue generated at sites of chronic inflammation is thought to be important in sustaining immunopathological processes, we have investigated whether structures resembling lymphoid follicles could be identified in the CNS of MS patients. Sections from post-mortem MS brains and spinal cords were screened using immunohistochemistry for the presence of CD20+ B-cells, CD3+ T-cells, CD138+ plasma cells and CD21+, CD35+ follicular dendritic cells, and for the expression of lymphoid chemokines (CXCL 13, CCL21) and peripheral node addressin (PNAd). Lymphoid follicle-like structures containing B-cells, T-cells and plasma cells, and a network of follicular dendritic cells producing CXCL13 were observed in the cerebral meninges of 2 out of 3 patients with secondary progressive MS, but not in relapsing remitting and primary progressive MS. We also show that proliferating B-cells are present in intrameningeal follicles, a finding which is suggestive of germinal center formation. No follicle-like structures were detected in parenchymal lesions. The formation of ectopic lymphoid follicies in the meninges of patients with MS could represent a critical step in maintaining humoral autoimmunity and in disease exacerbation.

  14. The Effect of Three Times a Week Glatiramer Acetate on Cerebral T1 Hypointense Lesions in Relapsing‐Remitting Multiple Sclerosis

    PubMed Central

    Dwyer, Michael G.; Ramasamy, Deepa P.; Davis, Mat D.; Steinerman, Joshua R.; Khan, Omar

    2015-01-01

    ABSTRACT BACKGROUND AND PURPOSE Two definitions of T1 hypointense (T1H) lesions can be derived from pre‐contrast images: those that may or may not have a corresponding gadolinium‐enhancing correlate on post‐contrast images (T1H total), and those that are simultaneously non‐gadolinium‐enhancing on post‐contrast scans (T1H non‐enhancing). To determine the differences in lesion evolution between these two T1H definitions, we examined the effect of glatiramer acetate 40 mg/mL three times weekly subcutaneous injection (GA40) on the number of new or enlarging T1H total and T1H non‐enhancing lesions in patients with relapsing‐remitting multiple sclerosis (RRMS). METHODS The Phase III GALA study randomized 1404 RRMS subjects 2:1 to receive GA40 or placebo for 12 months. MRI scans were obtained at baseline and at months 6 and 12. Cumulative numbers of T1H total and of T1H non‐enhancing lesions were analyzed using an adjusted negative binomial regression model. A total of 1,357 patients had MRI data collected at either the month 6 or month 12 visit. RESULTS Among the 1,357 patients with MRI scans performed at either the month 6 or month 12 visit, 883 treated with GA40 developed an adjusted cumulative mean of 1.72 T1H total lesions versus 2.62 in 440 placebo controls (risk ratio, .66; 95% CI, .54‐.80; P < .0001). On T1H non‐enhanced scans, GA40‐treated patients developed an adjusted cumulative mean of 1.35 T1H non‐enhancing lesions versus 1.91 in placebo controls (risk ratio, .71; CI, .58‐.87; P = .0009). CONCLUSIONS GA40 significantly reduced the number of new or enlarging T1H total lesions and T1H non‐enhancing lesions compared with placebo. Although the treatment effect magnitude was comparable with both definitions, the use of T1H non‐enhancing lesions may be more relevant for more uniform standardization in future clinical trials. PMID:26394270

  15. Glycopeptide-Based Antibody Detection in Multiple Sclerosis by Surface Plasmon Resonance

    PubMed Central

    Real-Fernández, Feliciana; Passalacqua, Irene; Peroni, Elisa; Chelli, Mario; Lolli, Francesco; Papini, Anna Maria; Rovero, Paolo

    2012-01-01

    In multiple sclerosis (MS) the gold standard for the diagnosis and prognosis is, up to now, the use of magnetic resonance imaging markers. No alternative simpler assays proven of use, except for cerebrospinal fluid analysis, have been provided in MS diagnosis. Therefore, there is a need to develop non-invasive, sensitive, simple new techniques for the clinical routine. Herein we present the evaluation of the feasibility of a glycopeptide-based biosensor to detect MS specific antibodies in sera using the surface plasmon resonance technology. The previously described glycopeptide antigen CSF114(Glc) has been immobilized on a gold sensor chip and the method has been optimized for real-time specific autoantibody detection directly in sera. A population of 60 healthy blood donors and 61 multiple sclerosis patients has been screened. The receiver operating characteristic (ROC)-based analysis has established the optimal diagnostic cut-off value for the method obtaining a sensitivity of 36% and a specificity of 95%. Sample sera have been also screened with a previously validated ELISA. PMID:22778603

  16. Targeting Experimental Autoimmune Encephalomyelitis Lesions to a Predetermined Axonal Tract System Allows for Refined Behavioral Testing in an Animal Model of Multiple Sclerosis

    PubMed Central

    Kerschensteiner, Martin; Stadelmann, Christine; Buddeberg, Bigna S.; Merkler, Doron; Bareyre, Florence M.; Anthony, Daniel C.; Linington, Christopher; Brück, Wolfgang; Schwab, Martin E.

    2004-01-01

    In multiple sclerosis (MS) the structural damage to axons determines the persistent clinical deficit patients acquire during the course of the disease. It is therefore important to test therapeutic strategies that can prevent or reverse this structural damage. The conventional animal model of MS, experimental autoimmune encephalomyelitis (EAE), typically shows disseminated inflammation in the central nervous system, which leads to a clinical deficit that cannot be directly attributed to a defined tract system. For this reason we have developed a localized EAE model, in which large inflammatory lesions are targeted to the dorsal columns of the spinal cord, an area including the corticospinal tract. These lesions show the pathological hallmarks of MS plaques and lead to reproducible and pronounced deficits in hindlimb locomotion. Because of the anatomical specificity of this technique we can now use highly sensitive behavioral tests that assess the functional integrity of specific axonal tracts. We show that these tests are predictive of the site and extent of a given lesion and are more sensitive for assessing the clinical course than the scales commonly used for disseminated EAE models. We believe that this targeted EAE model will become a helpful new tool for the evaluation of therapeutic approaches for MS that attempt to protect axons or support their repair. PMID:15039233

  17. Tuberous sclerosis complex presenting as bilateral large renal angiomyolipomas.

    PubMed

    Redkar, Neelam; Patil, Meenakshi Amit; Dhakate, Tushar; Kolhe, Prasad

    2012-01-01

    Tuberous sclerosis is an inherited disorder that can present with seizures, mental retardation, cutaneous lesions and visceral hamartomas, but can be entirely asymptomatic. The disease occurs in 1:100 000 persons in all races with nearly equal distribution between the sexes. Tuberous sclerosis is often associated with renal angiomyolipomas (AMLs), which occur in up to 80% of these patients. Here we report a case of a patient who presented with bilateral large renal AMLs and was detected to have tuberous sclerosis complex. PMID:22878994

  18. Time resolved optical detection for white matter lesion detection: preclinical tests on macaque brains and MRI co-registration

    NASA Astrophysics Data System (ADS)

    Planat-Chrétien, A.; Berger, M.; Hervé, L.; Watroba, L.; Demilly, J.; Flament, J.; Stimmer, L.; Aubourg, P.; Dinten, J.-M.

    2015-07-01

    We conducted a preclinical assessment on young macaques aimed at detecting white matter lesions. We present the protocol we implemented to achieve the lesions detection using a bedside non-invasive optical-based Time-Resolved instrumentation we have optimized for this purpose. We validated the reconstructed 3D absorption map with co-registration of MRI data.

  19. Neuroimaging in multiple sclerosis.

    PubMed

    Zivadinov, Robert; Cox, Jennifer L

    2007-01-01

    Conventional magnetic resonance imaging (MRI) has routinely been used to improve the accuracy of multiple sclerosis (MS) diagnosis and prognosis. Metrics derived from conventional MRI are now routinely used to detect therapeutic effects and extend clinical observations. However, conventional MRI measures, such as the use of lesion volume and count of gadolinium-enhancing and T2 lesions, have insufficient sensitivity and specificity to reveal the true degree of pathological changes occurring in MS. They cannot distinguish between inflammation, edema, demyelination, Wallerian degeneration, and axonal loss. In addition, they do not show a reliable correlation with clinical measures of disability and do not provide a complete assessment of therapeutic outcomes. Recent neuropathologic studies of typical chronic MS brains reveal macroscopic demyelination in cortical and deep gray matter (GM) that cannot be detected by currently available MRI techniques. Therefore, there is a pressing need for the development of newer MRI techniques to detect these lesions. Newer metrics of MRI analysis, including T1-weighted hypointense lesions, central nervous system atrophy measures, magnetization transfer imaging, magnetic resonance spectroscopy, and diffusion tensor imaging, are able to capture a more global picture of the range of tissue alterations caused by inflammation and neurodegeneration. At this time, they provide the only proof--albeit indirect--that important occult pathology is occurring in the GM. However, evidence is increasing that these nonconventional MRI measures correlate better with both existing and developing neurological impairment and disability when compared to conventional metrics. PMID:17531854

  20. Detection of sequences homologous to human retroviral DNA in multiple sclerosis by gene amplification

    SciTech Connect

    Greenberg, S.J.; Ehrlich, G.D.; Abbott, M.A.; Hurwitz, B.J.; Waldmann, T.A.; Poiesz, B.J. )

    1989-04-01

    Twenty-one patients with multiple sclerosis, chronic progressive type, were examined for DNA sequences homologous to a human retrovirus. Genomic DNA from peripheral blood mononuclear cells was analyzed for the presence of homologous sequences to the human T-cell leukemia/lymphoma virus type I (HTLV-I) long terminal repeat, 3{prime} gag, pol, and env domains by the enzymatic in vitro gene amplification technique, polymerase chain reaction. Positive identification of homologous pol sequences was made in the amplified DNA from six of these patients (29%). Three of these six patients (14%) also tested positive for the env region, but not for the other regions tested. In contrast, none of the samples from 35 normal individuals studied was positive when amplified and tested with the same primers and probes. Comparison of patterns obtained from controls and from patients with adult T-cell leukemia or tropical spastic paraparesis suggests that the DNA sequences identified are exogenous to the human genome and may correspond to a human retroviral species. The data support the detection of a human retroviral agent in some patients with multiple sclerosis.

  1. Effect of Treatment with Interferon Beta-1a on Changes in Voxel-Wise Magnetization Transfer Ratio in Normal Appearing Brain Tissue and Lesions of Patients with Relapsing–Remitting Multiple Sclerosis: A 24-Week, Controlled Pilot Study

    PubMed Central

    Zivadinov, Robert; Dwyer, Michael G.; Markovic-Plese, Silva; Kennedy, Cheryl; Bergsland, Niels; Ramasamy, Deepa P.; Durfee, Jacqueline; Hojnacki, David; Hayward, Brooke; Dangond, Fernando; Weinstock-Guttman, Bianca

    2014-01-01

    Background This pilot study investigated changes in remyelinating and demyelinating activity in normal appearing brain tissue (NABT) and lesions, by using voxel-wise magnetization transfer ratio (VW-MTR), in patients with relapsing–remitting multiple sclerosis (RRMS) receiving interferon beta-1a 44 mcg subcutaneously (IFN β-1a SC) three times weekly versus healthy controls (HCs) (NCT01085318). Methods Increasing (suggestive of remyelination) and decreasing (suggestive of demyelination) VW-MTR changes in NABT and in T2, T1 and gadolinium (Gd)-enhancing lesion volume were measured over 24 weeks in 23 patients treated with IFN β-1a SC and in 15 HCs (where applicable). VW-MTR changes were tested using the Wilcoxon signed–rank or Wilcoxon rank–sum test. Results A trend for greater volume of NABT with increasing VW-MTR at 24 weeks was observed for patients versus HCs (median [range] 1206 [0–15278]; 342 [0–951] mm3; p = 0.061). NABT volume with increasing VW-MTR at 12 weeks was significantly greater in patients than in HCs (852 [6–11577]; 360 [0–1755] mm3; p = 0.028). Similar findings were detected for lesion volumes. Two patients with notably high numbers of Gd-enhancing lesions at baseline had a markedly greater volume of tissue with increasing VW-MTR compared with other patients. Volume of NABT tissue with decreasing VW-MTR was significantly greater in patients versus HCs at 24 weeks (942 [0–6141]; 297 [0–852] mm3; p<0.001). Conclusions The significant change in NABT volume with increasing VW-MTR at 12 weeks suggests that active remyelination in patients with RRMS may occur during treatment with IFN β-1a SC. Findings from two patients with the highest number of Gd-enhancing lesions at baseline suggest that extensive remyelination in NABT may occur in patients with high disease activity. Tissue volume with decreasing VW-MTR was greater in patients than in HCs, despite treatment, validating the sensitivity of this technique for detecting MS

  2. Acrolein detection: potential theranostic utility in multiple sclerosis and spinal cord injury

    PubMed Central

    Tully, Melissa; Zheng, Lingxing; Shi, Riyi

    2015-01-01

    Oxidative stress has been implicated as a major pathological process underlying CNS disease and trauma. More specifically, acrolein, an unsaturated aldehyde, produced by way of lipid peroxidation, has been shown to play a crucial role in initiating and perpetuating detrimental effects associated with multiple sclerosis and spinal cord injury. In light of these findings, quantification of acrolein levels both systemically and locally could allow for the use of acrolein as a biomarker to aid in diagnosis and guide treatment regimens. The three main approaches currently available are acrolein derivatization followed byLC/GC–MS, application of an acrolein antibody and subsequent immunoblotting, and the 3-hydroxypropylmercapturic acid-based method. Of these three strategies, the 3-hydroxypropylmercapturic acid-based method is the least invasive allowing for rapid translation of acrolein detection into a clinical setting. PMID:24831349

  3. Acrolein detection: potential theranostic utility in multiple sclerosis and spinal cord injury.

    PubMed

    Tully, Melissa; Zheng, Lingxing; Shi, Riyi

    2014-06-01

    Oxidative stress has been implicated as a major pathological process underlying CNS disease and trauma. More specifically, acrolein, an unsaturated aldehyde, produced by way of lipid peroxidation, has been shown to play a crucial role in initiating and perpetuating detrimental effects associated with multiple sclerosis and spinal cord injury. In light of these findings, quantification of acrolein levels both systemically and locally could allow for the use of acrolein as a biomarker to aid in diagnosis and guide treatment regimens. The three main approaches currently available are acrolein derivatization followed by LC/GC-MS, application of an acrolein antibody and subsequent immunoblotting, and the 3-hydroxypropylmercapturic acid-based method. Of these three strategies, the 3-hydroxypropylmercapturic acid-based method is the least invasive allowing for rapid translation of acrolein detection into a clinical setting.

  4. The Diagnostic Value of Superb Microvascular Imaging (SMI) in Detecting Blood Flow Signals of Breast Lesions

    PubMed Central

    Ma, Yan; Li, Gang; Li, Jing; Ren, Wei-dong

    2015-01-01

    Abstract The correlation between color Doppler flow imaging (CDFI) and Superb Microvascular Imaging (SMI) for detecting blood flow in breast lesions was investigated, as was the diagnostic value of SMI in differentiating benign from malignant breast lesions. These lesions were evaluated using both CDFI and SMI according to Adler's method. Pathologic examination showed 57 malignant lesions and 66 benign lesions. The number of blood vessels in a single mass was detected by 2 techniques (SMI and CDFI), and the difference between the 2 values (SMI-CDFI) was calculated. The optimal threshold for the diagnosis of malignant neoplasms and the diagnostic performances of SMI, CDFI, and SMI-CDFI were calculated. For the total lesions and malignant lesions alone, the difference between SMI and CDFI for detecting blood flow was significant (P < 0.01), but the difference was not significant for benign lesions (P = 0.15). The area under the receiver operating characteristic curve was 0.73 (95% confidence interval [CI]: 0.64–0.82) for CDFI; 0.81 (95% CI: 0.74–0.89) for SMI; and 0.89 (95% CI: 0.82–0.95) for SMI-CDFI. Furthermore, the modality of “SMI-CDFI” showed the best diagnostic performance. SMI provides further microvessel information in breast lesions. The diagnostic modality of “SMI-CDFI” can improve the diagnostic performance of ultrasound in the differentiation between benign and malignant masses. PMID:26356718

  5. Interleukin-17- and interleukin-22-secreting myelin-specific CD4(+) T cells resistant to corticoids are related with active brain lesions in multiple sclerosis patients.

    PubMed

    Wing, Ana Cristina; Hygino, Joana; Ferreira, Thais B; Kasahara, Taissa M; Barros, Priscila O; Sacramento, Priscila M; Andrade, Regis M; Camargo, Solange; Rueda, Fernanda; Alves-Leon, Soniza V; Vasconcelos, Claudia Cristina; Alvarenga, Regina; Bento, Cleonice A M

    2016-02-01

    Multiple sclerosis (MS) is thought to be an autoimmune disorder. It is believed that immunological events in the early stages have great impact on the disease course. Therefore, we aimed to evaluate the cytokine profile of myelin basic protein (MBP)-specific T cells from MS patients in the early phase of the disease and correlate it to clinical parameters, as well as to the effect of in vitro corticoid treatment. Peripheral T cells from MS patients were stimulated with MBP with our without hydrocortisone for 5 days. The cytokines level were determined by ELISA. The number of active brain lesions was determined by MRI scans, and the neurological disabilities were assessed by Expanded Disability Status Scale scores. Our results demonstrated that MS-derived T cells responded to MBP by producing high levels of T helper type 1 (Th1) and Th17 cytokines. Although the production of interleukin-6 (IL-6), granulocyte-macrophage colony-stimulating factor, IL-17 and IL-22 was less sensitive to hydrocortisone inhibition, only IL-17 and IL-22 levels correlated with active brain lesions. The ability of hydrocortisone to inhibit IL-17 and IL-22 production by MBP-specific CD4(+) T cells was inversely related to the number of active brain lesions. Finally, the production of both cytokines was significantly higher in cell cultures from Afrodescendant patients and it was less sensitive to hydrocortisone inhibition. In summary, our data suggest that IL-17- and IL-22-secreting CD4(+) T cells resistant to corticoids are associated with radiological activity of the MS in early stages of the disease, mainly among Afrodescendant patients who, normally, have worse prognosis.

  6. Comprehensive analysis of human endogenous retrovirus group HERV-W locus transcription in multiple sclerosis brain lesions by high-throughput amplicon sequencing.

    PubMed

    Schmitt, Katja; Richter, Christin; Backes, Christina; Meese, Eckart; Ruprecht, Klemens; Mayer, Jens

    2013-12-01

    Human endogenous retroviruses (HERVs) of the HERV-W group comprise hundreds of loci in the human genome. Deregulated HERV-W expression and HERV-W locus ERVWE1-encoded Syncytin-1 protein have been implicated in the pathogenesis of multiple sclerosis (MS). However, the actual transcription of HERV-W loci in the MS context has not been comprehensively analyzed. We investigated transcription of HERV-W in MS brain lesions and white matter brain tissue from healthy controls by employing next-generation amplicon sequencing of HERV-W env-specific reverse transcriptase (RT) PCR products, thus revealing transcribed HERV-W loci and the relative transcript levels of those loci. We identified more than 100 HERV-W loci that were transcribed in the human brain, with a limited number of loci being predominantly transcribed. Importantly, relative transcript levels of HERV-W loci were very similar between MS and healthy brain tissue samples, refuting deregulated transcription of HERV-W env in MS brain lesions, including the high-level-transcribed ERVWE1 locus encoding Syncytin-1. Quantitative RT-PCR likewise did not reveal differences in MS regarding HERV-W env general transcript or ERVWE1- and ERVWE2-specific transcript levels. However, we obtained evidence for interindividual differences in HERV-W transcript levels. Reporter gene assays indicated promoter activity of many HERV-W long terminal repeats (LTRs), including structurally incomplete LTRs. Our comprehensive analysis of HERV-W transcription in the human brain thus provides important information on the biology of HERV-W in MS lesions and normal human brain, implications for study design, and mechanisms by which HERV-W may (or may not) be involved in MS.

  7. Computer-Aided Detection of Exophytic Renal Lesions on Non-Contrast CT Images

    PubMed Central

    Liu, Jianfei; Wang, Shijun; Linguraru, Marius George; Yao, Jianhua; Summers, Ronald M.

    2014-01-01

    Renal lesions are important extracolonic findings on computed tomographic colonography (CTC). They are difficult to detect on non-contrast CTC images due to low image contrast with surrounding objects. In this paper, we developed a novel computer-aided diagnosis system to detect a subset of renal lesions, exophytic lesions, by 1) exploiting efficient belief propagation to segment kidneys, 2) establishing an intrinsic manifold diffusion on kidney surface, 3) searching for potential lesion-caused protrusions with local maximum diffusion response, and 4) exploring novel shape descriptors, including multi-scale diffusion response, with machine learning to classify exophytic renal lesions. Experimental results on the validation dataset with 167 patients revealed that manifold diffusion significantly outperformed conventional shape features (p < 1e − 3) and resulted in 95% sensitivity with 15 false positives per patient for detecting exophytic renal lesions. Five-fold cross-validation also demonstrated that our method could stably detect exophytic renal lesions. These encouraging results demonstrated that manifold diffusion is a key means to enable accurate computer-aided diagnosis of renal lesions. PMID:25189363

  8. Statistical approach for detecting cancer lesions from prostate ultrasound images

    NASA Astrophysics Data System (ADS)

    Houston, A. G.; Premkumar, Saganti B.; Babaian, Richard J.; Pitts, David E.

    1993-07-01

    Sequential digitized cross-sectional ultrasound image planes of several prostates have been studied at the pixel level during the past year. The statistical distribution of gray scale values in terms of simple statistics, sample means and sample standard deviations, have been considered for estimating the differences between cross-sectional image planes of the gland due to the presence of cancer lesions. Based on a variability measure, the results for identifying the presence of cancer lesions in the peripheral zone of the gland for 25 blind test cases were found to be 64% accurate. This accuracy is higher than that obtained by visual photo interpretation of the image data, though not as high as our earlier results were indicating. Axial-view ultrasound image planes of prostate glands were obtained from the apex to the base of the gland at 2 mm intervals. Results for the 25 different prostate glands, which include pathologically confirmed benign and cancer cases, are presented.

  9. Validation of White-Matter Lesion Change Detection Methods on a Novel Publicly Available MRI Image Database.

    PubMed

    Lesjak, Žiga; Pernuš, Franjo; Likar, Boštjan; Špiclin, Žiga

    2016-10-01

    Changes of white-matter lesions (WMLs) are good predictors of the progression of neurodegenerative diseases like multiple sclerosis (MS). Based on longitudinal magnetic resonance (MR) imaging the changes can be monitored, while the need for their accurate and reliable quantification led to the development of several automated MR image analysis methods. However, an objective comparison of the methods is difficult, because publicly unavailable validation datasets with ground truth and different sets of performance metrics were used. In this study, we acquired longitudinal MR datasets of 20 MS patients, in which brain regions were extracted, spatially aligned and intensity normalized. Two expert raters then delineated and jointly revised the WML changes on subtracted baseline and follow-up MR images to obtain ground truth WML segmentations. The main contribution of this paper is an objective, quantitative and systematic evaluation of two unsupervised and one supervised intensity based change detection method on the publicly available datasets with ground truth segmentations, using common pre- and post-processing steps and common evaluation metrics. Besides, different combinations of the two main steps of the studied change detection methods, i.e. dissimilarity map construction and its segmentation, were tested to identify the best performing combination.

  10. Validation of White-Matter Lesion Change Detection Methods on a Novel Publicly Available MRI Image Database.

    PubMed

    Lesjak, Žiga; Pernuš, Franjo; Likar, Boštjan; Špiclin, Žiga

    2016-10-01

    Changes of white-matter lesions (WMLs) are good predictors of the progression of neurodegenerative diseases like multiple sclerosis (MS). Based on longitudinal magnetic resonance (MR) imaging the changes can be monitored, while the need for their accurate and reliable quantification led to the development of several automated MR image analysis methods. However, an objective comparison of the methods is difficult, because publicly unavailable validation datasets with ground truth and different sets of performance metrics were used. In this study, we acquired longitudinal MR datasets of 20 MS patients, in which brain regions were extracted, spatially aligned and intensity normalized. Two expert raters then delineated and jointly revised the WML changes on subtracted baseline and follow-up MR images to obtain ground truth WML segmentations. The main contribution of this paper is an objective, quantitative and systematic evaluation of two unsupervised and one supervised intensity based change detection method on the publicly available datasets with ground truth segmentations, using common pre- and post-processing steps and common evaluation metrics. Besides, different combinations of the two main steps of the studied change detection methods, i.e. dissimilarity map construction and its segmentation, were tested to identify the best performing combination. PMID:27207310

  11. How do radiographic techniques affect mass lesion detection performance in digital mammography?

    NASA Astrophysics Data System (ADS)

    Huda, Walter; Ogden, Kent M.; Scalzetti, Ernest M.; Dudley, Eric F.; Dance, David R.

    2004-05-01

    We investigated how the x-ray tube kV and mAs affected the detection of simulated lesions with diameters between 0.24 and 12 mm. Digital mammograms were acquired with and without mass lesions, permitting a difference image to be generated corresponding to the lesion alone. Isolated digital lesions were added at a reduced intensity to non-lesion images, and used in Four-Alternate Forced Choice (4-AFC) experiments to determine the lesion intensity that corresponded to an accuracy of 92% (I92%). Values of I92% were determined at x-ray tube output values ranging from 40 to 120 mAs, and x-ray tube voltages ranging from 24 to 32 kV. For mass lesions larger than ~0.8 mm, there was no significant change in detection peformance with changing mAs. Doubling of the x-ray tube output from 60 to 120 mAs resulted in an average change in I92% of only +3.8%, whereas the Rose model of lesion detection predicts a reduction in the experimental value of I92% of -29%. For the 0.24 mm lesion, however, reducing the x-ray beam mAs from 100 to 40 mAs reduced the average detection performance by ~60%. Contrast-detail curves for lesions with diameter >= 0.8 mm had a slope of ~+0.23, whereas the Rose model predicts a slope of -0.5. For lesions smaller than ~0.8 mm, contrast-detail slopes were all negative with the average gradient increasing with decreasing mAs value. Increasing the x-ray tube voltage from 24 to 32 kV at a constant display contrast resulted in a modest improvement in low contrast lesion detection performance of ~10%. Increasing the display window width from 2000 to 2500 reduced the average observer performance by ~6%. Our principal finding is that radiographic technique factors have little effect on detection performance for lesions larger than ~0.8 mm, but that the visibility of smaller lesions is affected by quantum mottle in qualitative agreement with the predictions of the Rose model.

  12. Evaluation of radiography, ultrasonography and endoscopy for detection of shell lesions in live abalone Haliotis iris (Mollusca: Gastropoda).

    PubMed

    Nollens, Hendrik H; Schofield, John C; Keogh, Jonathan A; Probert, P Keith

    2002-07-01

    Radiography, ultrasonography and endoscopy were examined for their efficacy as non-destructive techniques for the detection of shell lesions in the marine gastropod Haliotis iris Gmelin. X-rays provided 69% correct diagnoses, with detection being restricted to those lesions which were mineralised. Ultrasound also showed potential to reliably detect lesions (83% correct diagnoses), but only where the lesions demonstrated a clear 3-dimensional relief. Lesion dimensions were underestimated using ultrasound. Endoscopy, applied to anaesthetised individuals, provided the most accurate method (92% correct diagnoses) for lesion detection and, although invasive, had no discernible effect on survival of the abalone 8 mo after screening.

  13. Structured learning algorithm for detection of nonobstructive and obstructive coronary plaque lesions from computed tomography angiography

    PubMed Central

    Kang, Dongwoo; Dey, Damini; Slomka, Piotr J.; Arsanjani, Reza; Nakazato, Ryo; Ko, Hyunsuk; Berman, Daniel S.; Li, Debiao; Kuo, C.-C. Jay

    2015-01-01

    Abstract. Visual identification of coronary arterial lesion from three-dimensional coronary computed tomography angiography (CTA) remains challenging. We aimed to develop a robust automated algorithm for computer detection of coronary artery lesions by machine learning techniques. A structured learning technique is proposed to detect all coronary arterial lesions with stenosis ≥25%. Our algorithm consists of two stages: (1) two independent base decisions indicating the existence of lesions in each arterial segment and (b) the final decision made by combining the base decisions. One of the base decisions is the support vector machine (SVM) based learning algorithm, which divides each artery into small volume patches and integrates several quantitative geometric and shape features for arterial lesions in each small volume patch by SVM algorithm. The other base decision is the formula-based analytic method. The final decision in the first stage applies SVM-based decision fusion to combine the two base decisions in the second stage. The proposed algorithm was applied to 42 CTA patient datasets, acquired with dual-source CT, where 21 datasets had 45 lesions with stenosis ≥25%. Visual identification of lesions with stenosis ≥25% by three expert readers, using consensus reading, was considered as a reference standard. Our method performed with high sensitivity (93%), specificity (95%), and accuracy (94%), with receiver operator characteristic area under the curve of 0.94. The proposed algorithm shows promising results in the automated detection of obstructive and nonobstructive lesions from CTA. PMID:26158081

  14. Induced sputum as a method for detection of systemic sclerosis-related interstitial lung disease.

    PubMed

    Yilmaz, Neslihan; Abul, Yasin; Bicakcigil, Muge; Golabi, Pejman; Celikel, Cigdem; Karakurt, Sait; Yavuz, Sule

    2012-07-01

    Inducted sputum (IS) is a non-invasive procedure that can be used for collection of airway secretions. The aim of our study is to evaluate the clinical usefulness of IS for detection of airway inflammation in systemic sclerosis (SSc). Bronchoalveolar lavage and IS were performed to 20 patients with SSc. Eighteen patients who were referred to pulmonary medicine for bronchoalveolar lavage due to other reasons were also recruited for cell counts comparisons. Spirometry, echocardiography and thorax CT (HRCT) imaging were also performed to all patients. Mean macrophage and lymphocyte counts were found to be increased in IS of SSc patients compared with that of control (58.4 ± 14.5% vs. 31.3 ± 16.3%, 30.2 ± 15.4% vs. 15.0 ± 11.5% P < 0.001), whereas mean neutrophil count was lower in the SSc patients (4.1 ± 4.5% vs. 17.2 ± 13.1%, P < 0.05). Significant correlations were noted between BAL and IS findings for macrophage (r = 0.55, P = 0.02) lymphocyte (r = 0.65, P < 0.01) and total cell counts (r = 0.45, P = 0.06). IS is an easy and reliable method for the detection of alveolitis and can be used for early detection of lung involvement in scleroderma.

  15. Breast Imaging Reporting and Data System Category 3 Lesions Detected on Whole-Breast Screening Ultrasound

    PubMed Central

    Nam, Sang Yu; Ko, Eun Young; Han, Boo-Kyung; Shin, Jung Hee; Hahn, Soo Yeon

    2016-01-01

    Purpose This study assessed the incidence and cancer rate of probably benign lesions detected on bilateral whole-breast screening ultrasound (US), which corresponded to US Breast Imaging Reporting and Data System (BI-RADS) category 3, and evaluated the proper management of those lesions. Methods This study was approved by the Institutional Review Board in our institution, which waived informed patient consent. We retrospectively reviewed US images of 1,666 patients who underwent bilateral whole-breast screening US as a supplemental screening test to negative screening mammography or screening US only. The incidence, clinical course, and cancer rate of screening US-detected probably benign lesions corresponding to US BI-RADS category 3 were investigated, and the size and multiplicity of screening US-detected category 3 lesions were evaluated. Results Probably benign lesions corresponding to US BI-RADS category 3 were detected in 689 of 1,666 patients (41.4%) who underwent screening US. Among them, 653 had follow-up US images for at least 24 months, and among these 653, 190 (29.1%) had multiple bilateral category 3 lesions. Moreover, 539 of 1,666 patients (32.4%) had lesions ≤1 cm in size and 114 of 1,666 (6.8%) had lesions >1 cm (median, 0.82 cm; range, 0.3–4.2 cm). Four of the 653 patients (0.6%) showed suspicious interval changes and were categorized into BI-RADS category 4. Biopsy analysis confirmed only one lesion as invasive ductal carcinoma at the 6-month follow-up; another lesion was an intraductal papilloma and the remaining two were fibroadenomas. Overall cancer rate of the screening US-detected BI-RADS category 3 lesions was 0.2%. Conclusion The incidence of category 3 lesions detected on screening US only was very high, but the cancer rate was very low. Therefore, in an average-risk population, routine screening US is preferable over short-term follow-up for BI-RADS category 3 lesions detected on whole-breast screening US. PMID:27721880

  16. Automated lesion detection in dynamic contrast enhanced magnetic resonance imaging of breast

    NASA Astrophysics Data System (ADS)

    Liang, Xi; Kotagiri, Romamohanarao; Frazer, Helen; Yang, Qing

    2015-03-01

    We propose an automated method in detecting lesions to assist radiologists in interpreting dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) of breast. The aim is to highlight the suspicious regions of interest to reduce the searching time of the lesions and the possibility of radiologists overlooking small regions. In our method, we locate the suspicious regions by applying a threshold on essential features. The features are normalized to reduce the variation between patients. Support vector machine classifier is then applied to exclude normal tissues from these regions, using both kinetic and morphological features extracted in the lesions. In the evaluation of the system on 21 patients with 50 lesions, all lesions were successfully detected with 5.02 false positive regions per breast.

  17. Image patch-based method for automated classification and detection of focal liver lesions on CT

    NASA Astrophysics Data System (ADS)

    Safdari, Mustafa; Pasari, Raghav; Rubin, Daniel; Greenspan, Hayit

    2013-03-01

    We developed a method for automated classification and detection of liver lesions in CT images based on image patch representation and bag-of-visual-words (BoVW). BoVW analysis has been extensively used in the computer vision domain to analyze scenery images. In the current work we discuss how it can be used for liver lesion classification and detection. The methodology includes building a dictionary for a training set using local descriptors and representing a region in the image using a visual word histogram. Two tasks are described: a classification task, for lesion characterization, and a detection task in which a scan window moves across the image and is determined to be normal liver tissue or a lesion. Data: In the classification task 73 CT images of liver lesions were used, 25 images having cysts, 24 having metastasis and 24 having hemangiomas. A radiologist circumscribed the lesions, creating a region of interest (ROI), in each of the images. He then provided the diagnosis, which was established either by biopsy or clinical follow-up. Thus our data set comprises 73 images and 73 ROIs. In the detection task, a radiologist drew ROIs around each liver lesion and two regions of normal liver, for a total of 159 liver lesion ROIs and 146 normal liver ROIs. The radiologist also demarcated the liver boundary. Results: Classification results of more than 95% were obtained. In the detection task, F1 results obtained is 0.76. Recall is 84%, with precision of 73%. Results show the ability to detect lesions, regardless of shape.

  18. Epstein–Barr virus infection is not a characteristic feature of multiple sclerosis brain

    PubMed Central

    Willis, Simon N.; Stadelmann, Christine; Rodig, Scott J.; Caron, Tyler; Gattenloehner, Stefan; Mallozzi, Scott S.; Roughan, Jill E.; Almendinger, Stefany E.; Blewett, Megan M.; Brück, Wolfgang; Hafler, David A.

    2009-01-01

    Multiple sclerosis is an inflammatory demyelinating disease of the central nervous system (CNS) that is thought to be caused by a combination of genetic and environmental factors. To date, considerable evidence has associated Epstein–Barr virus (EBV) infection with disease development. However, it remains controversial whether EBV infects multiple sclerosis brain and contributes directly to CNS immunopathology. To assess whether EBV infection is a characteristic feature of multiple sclerosis brain, a large cohort of multiple sclerosis specimens containing white matter lesions (nine adult and three paediatric cases) with a heterogeneous B cell infiltrate and a second cohort of multiple sclerosis specimens (12 cases) that included B cell infiltration within the meninges and parenchymal B cell aggregates, were examined for EBV infection using multiple methodologies including in situ hybridization, immunohistochemistry and two independent real-time polymerase chain reaction (PCR) methodologies that detect genomic EBV or the abundant EBV encoded RNA (EBER) 1, respectively. We report that EBV could not be detected in any of the multiple sclerosis specimens containing white matter lesions by any of the methods employed, yet EBV was readily detectable in multiple Epstein–Barr virus-positive control tissues including several CNS lymphomas. Furthermore, EBV was not detected in our second cohort of multiple sclerosis specimens by in situ hybridization. However, our real-time PCR methodologies, which were capable of detecting very few EBV infected cells, detected EBV at low levels in only 2 of the 12 multiple sclerosis meningeal specimens examined. Our finding that CNS EBV infection was rare in multiple sclerosis brain indicates that EBV infection is unlikely to contribute directly to multiple sclerosis brain pathology in the vast majority of cases. PMID:19638446

  19. Melanoma and other skin lesion detection using smart handheld devices.

    PubMed

    Zouridakis, George; Wadhawan, Tarun; Situ, Ning; Hu, Rui; Yuan, Xiaojing; Lancaster, Keith; Queen, Courtney M

    2015-01-01

    Smartphones of the latest generation featuring advanced multicore processors, dedicated microchips for graphics, high-resolution cameras, and innovative operating systems provide a portable platform for running sophisticated medical screening software and delivering point-of-care patient diagnostic services at a very low cost. In this chapter, we present a smartphone digital dermoscopy application that can analyze high-resolution images of skin lesions and provide the user with feedback about the likelihood of malignancy. The same basic procedure has been adapted to evaluate other skin lesions, such as the flesh-eating bacterial disease known as Buruli ulcer. When implemented on the iPhone, the accuracy and speed achieved by this application are comparable to that of a desktop computer, demonstrating that smartphone applications can combine portability and low cost with high performance. Thus, smartphone-based systems can be used as assistive devices by primary care physicians during routine office visits, and they can have a significant impact in underserved areas and in developing countries, where health-care infrastructure is limited.

  20. Melanoma and other skin lesion detection using smart handheld devices.

    PubMed

    Zouridakis, George; Wadhawan, Tarun; Situ, Ning; Hu, Rui; Yuan, Xiaojing; Lancaster, Keith; Queen, Courtney M

    2015-01-01

    Smartphones of the latest generation featuring advanced multicore processors, dedicated microchips for graphics, high-resolution cameras, and innovative operating systems provide a portable platform for running sophisticated medical screening software and delivering point-of-care patient diagnostic services at a very low cost. In this chapter, we present a smartphone digital dermoscopy application that can analyze high-resolution images of skin lesions and provide the user with feedback about the likelihood of malignancy. The same basic procedure has been adapted to evaluate other skin lesions, such as the flesh-eating bacterial disease known as Buruli ulcer. When implemented on the iPhone, the accuracy and speed achieved by this application are comparable to that of a desktop computer, demonstrating that smartphone applications can combine portability and low cost with high performance. Thus, smartphone-based systems can be used as assistive devices by primary care physicians during routine office visits, and they can have a significant impact in underserved areas and in developing countries, where health-care infrastructure is limited. PMID:25626557

  1. An N-glucosylated peptide detecting disease-specific autoantibodies, biomarkers of multiple sclerosis

    PubMed Central

    Lolli, Francesco; Mulinacci, Barbara; Carotenuto, Alfonso; Bonetti, Bruno; Sabatino, Giuseppina; Mazzanti, Benedetta; D'Ursi, Anna Maria; Novellino, Ettore; Pazzagli, Marta; Lovato, Laura; Alcaro, Maria C.; Peroni, Elisa; Pozo-Carrero, Maria C.; Nuti, Francesca; Battistini, Luca; Borsellino, Giovanna; Chelli, Mario; Rovero, Paolo; Papini, Anna Maria

    2005-01-01

    Multiple sclerosis (MS) is a complex disease that seems to depend on several pathophysiological processes. Because of its varied clinical presentation, natural history, and response to therapeutic interventions, MS can be considered to be a group of diseases that have not been yet characterized, thus resulting in difficult evaluation of prognosis. In the last few years, the role of autoAbs in MS has been reevaluated, and, therefore, their identification as specific biomarkers became a relevant target. In this paper, we demonstrate that an aberrant N-glucosylation is a fundamental determinant of autoAb recognition in MS. Thus, we developed CSF114(Glc), an antigenic probe accurately measuring IgM autoAbs in the sera of a patient population, as disease biomarker. The relevance of CSF114(Glc) is demonstrated by its clinical application and correlation with disease activity and prognosis. In fact, CSF114(Glc), a structure-based designed glycopeptide, is able to recognize, by ELISA, the presence of specific IgM autoAbs in the sera of a MS patient population but not in blood donors and other autoimmune conditions. AutoAbs specific for CSF114(Glc) isolated from MS patients recognized myelin and oligodendrocyte antigens by immunohistochemistry but not other nonrelevant tissues. We demonstrate that CSF114(Glc) is a reliable, specific probe in a longitudinal study of untreated MS patients. Development of IgG/IgM anti-CSF114(Glc) Abs paralleled clinical activity and brain lesions positive to MRI. Therefore, a CSF114(Glc)-based immunoassay on sera may have important prognostic value in monitoring MS disease progression guiding optimal therapeutic treatment. PMID:16014416

  2. Detection of JCPyV microRNA in blood and urine samples of multiple sclerosis patients under natalizumab therapy.

    PubMed

    Giovannelli, Irene; Martelli, Francesco; Repice, Anna; Massacesi, Luca; Azzi, Alberta; Giannecchini, Simone

    2015-12-01

    Polyomavirus JC (JCPyV) reactivation and development of progressive multifocal leukoencephalopathy is a health concern in multiple sclerosis patients under natalizumab therapy. Here, the JCPyV microRNA-J1-3p and microRNA-J1-5p expressions and genomic variability were investigated in blood and urine samples of multiple sclerosis patients before and under natalizumab therapy and in healthy controls. The two JCPyV microRNAs were detected in the JCPyV-DNA-positive peripheral blood mononuclear cell samples and in the exosomes derived from plasma and urine obtained from JCPyV-DNA-positive and JCPyV-DNA-negative patients. In particular, the increased JCPyV microRNA expression in samples of multiple sclerosis patients under natalizumab therapy was consistent with the high JCPyV-DNA positivity observed in these samples. Moreover, JCPyV microRNA genomic region showed few nucleotide differences in samples obtained from blood and urine of multiple sclerosis patients and healthy controls. Overall, these data suggest a potential role of the JCPyV microRNA expression in counteracting the viral reactivation to maintain JCPyV asymptomatic persistence in the host.

  3. Points of interest and visual dictionaries for automatic retinal lesion detection.

    PubMed

    Rocha, A; Carvalho, T; Jelinek, H F; Goldenstein, S; Wainer, J

    2012-08-01

    In this paper, we present an algorithm to detect the presence of diabetic retinopathy (DR)-related lesions from fundus images based on a common analytical approach that is capable of identifying both red and bright lesions without requiring specific pre- or postprocessing. Our solution constructs a visual word dictionary representing points of interest (PoIs) located within regions marked by specialists that contain lesions associated with DR and classifies the fundus images based on the presence or absence of these PoIs as normal or DR-related pathology. The novelty of our approach is in locating DR lesions in the optic fundus images using visual words that combines feature information contained within the images in a framework easily extendible to different types of retinal lesions or pathologies and builds a specific projection space for each class of interest (e.g., white lesions such as exudates or normal regions) instead of a common dictionary for all classes. The visual words dictionary was applied to classifying bright and red lesions with classical cross validation and cross dataset validation to indicate the robustness of this approach. We obtained an area under the curve (AUC) of 95.3% for white lesion detection and an AUC of 93.3% for red lesion detection using fivefold cross validation and our own data consisting of 687 images of normal retinae, 245 images with bright lesions, 191 with red lesions, and 109 with signs of both bright and red lesions. For cross dataset analysis, the visual dictionary also achieves compelling results using our images as the training set and the RetiDB and Messidor images as test sets. In this case, the image classification resulted in an AUC of 88.1% when classifying the RetiDB dataset and in an AUC of 89.3% when classifying the Messidor dataset, both cases for bright lesion detection. The results indicate the potential for training with different acquisition images under different setup conditions with a high accuracy of

  4. Relevance of Partitioning DLCO to Detect Pulmonary Hypertension in Systemic Sclerosis

    PubMed Central

    Wémeau-Stervinou, Lidwine; De Groote, Pascal; Remy-Jardin, Martine; Denis, Guillaume; Lambert, Marc; Lamblin, Nicolas; Morell-Dubois, Sandrine; Fertin, Marie; Lefevre, Guillaume; Sobanski, Vincent; Le Rouzic, Olivier; Hatron, Pierre-Yves; Wallaert, Benoit; Hachulla, Eric; Perez, Thierry

    2013-01-01

    We investigated whether partitioning DLCO into membrane conductance for CO (DmCO) and pulmonary capillary blood volume (Vcap) was helpful in suspecting precapillary pulmonary (arterial) hypertension (P(A)H) in systemic sclerosis (SSc) patients with or without interstitial lung disease (ILD). We included 63 SSc patients with isolated PAH (n=6), isolated ILD (n=19), association of both (n=12) or without PAH and ILD (n=26). Partitioning of DLCO was performed by the combined DLNO/DLCO method. DLCO, DmCO and Vcap were equally reduced in patients with isolated PAH and patients with isolated ILD but Vcap/alveolar volume (VA) ratio was significantly lower in the isolated PAH group. In patients without ILD, DLCO, DmCO, Vcap and Vcap/VA ratio were reduced in patients with isolated PAH when compared to patients without PAH and both Vcap/VA and DLCO had the highest AUC to detect PAH. In patients with ILD, Vcap had the highest AUC and performed better than DLCO to detect PH in this subgroup. In conclusion, Vcap/VA was lower in PAH than in ILD in SSC whereas DLCO was not different. Vcap/VA ratio and DLCO had similar high performance to detect PAH in patients without ILD. Vcap had better AUC than DLCO, DmCO and FVC/DLCO ratio to detect PH in SSC patients with ILD. These results suggest that partitioning of DLCO might be of interest to detect P(A)H in SSC patients with or without ILD. PMID:24205063

  5. Advances in Optical Adjunctive Aids for Visualisation and Detection of Oral Malignant and Potentially Malignant Lesions

    PubMed Central

    Bhatia, Nirav; Lalla, Yastira; Vu, An N.; Farah, Camile S.

    2013-01-01

    Traditional methods of screening for oral potentially malignant disorders and oral malignancies involve a conventional oral examination with digital palpation. Evidence indicates that conventional examination is a poor discriminator of oral mucosal lesions. A number of optical aids have been developed to assist the clinician to detect oral mucosal abnormalities and to differentiate benign lesions from sinister pathology. This paper discusses advances in optical technologies designed for the detection of oral mucosal abnormalities. The literature regarding such devices, VELscope and Identafi, is critically analysed, and the novel use of Narrow Band Imaging within the oral cavity is also discussed. Optical aids are effective in assisting with the detection of oral mucosal abnormalities; however, further research is required to evaluate the usefulness of these devices in differentiating benign lesions from potentially malignant and malignant lesions. PMID:24078812

  6. Spinal focal lesion detection in multiple myeloma using multimodal image features

    NASA Astrophysics Data System (ADS)

    Fränzle, Andrea; Hillengass, Jens; Bendl, Rolf

    2015-03-01

    Multiple myeloma is a tumor disease in the bone marrow that affects the skeleton systemically, i.e. multiple lesions can occur in different sites in the skeleton. To quantify overall tumor mass for determining degree of disease and for analysis of therapy response, volumetry of all lesions is needed. Since the large amount of lesions in one patient impedes manual segmentation of all lesions, quantification of overall tumor volume is not possible until now. Therefore development of automatic lesion detection and segmentation methods is necessary. Since focal tumors in multiple myeloma show different characteristics in different modalities (changes in bone structure in CT images, hypointensity in T1 weighted MR images and hyperintensity in T2 weighted MR images), multimodal image analysis is necessary for the detection of focal tumors. In this paper a pattern recognition approach is presented that identifies focal lesions in lumbar vertebrae based on features from T1 and T2 weighted MR images. Image voxels within bone are classified using random forests based on plain intensities and intensity value derived features (maximum, minimum, mean, median) in a 5 x 5 neighborhood around a voxel from both T1 and T2 weighted MR images. A test data sample of lesions in 8 lumbar vertebrae from 4 multiple myeloma patients can be classified at an accuracy of 95% (using a leave-one-patient-out test). The approach provides a reasonable delineation of the example lesions. This is an important step towards automatic tumor volume quantification in multiple myeloma.

  7. Uniform detection of immunoglobulin-gene rearrangement in benign lymphoepithelial lesions.

    PubMed

    Fishleder, A; Tubbs, R; Hesse, B; Levine, H

    1987-04-30

    The term "benign lymphoepithelial lesion" is used to describe the salivary-gland lymphocytic infiltration and epithelial changes typically found in association with Sjögren's syndrome. We used Southern blot hybridization techniques to examine the immunoglobulin genes in salivary-gland tissue derived from eight patients with benign lymphoepithelial lesions. Three of these patients had intrasalivary non-Hodgkin's lymphoma complicating the lesions, whereas the lesions in the remaining five were all histologically benign. Ten samples from the eight patients all revealed rearrangement of both the heavy-chain and light-chain immunoglobulin genes. In one of the patients in whom non-Hodgkin's lymphoma involved both the salivary-gland lesion and an ipsilateral lymph node, the rearrangements of the heavy-chain and light-chain immunoglobulin genes detected at the two sites were identical. One other patient had two distinct benign lymphoepithelial lesions removed two years apart. The rearrangements of the heavy-chain as well as the kappa light-chain genes detected in these two lesions were entirely different. These data suggest that B-cell clonal expansion has an integral role in the pathophysiology of the benign lymphoepithelial lesion and may explain the increased incidence of lymphoma noted in association with this disorder.

  8. Multi-stage osteolytic spinal bone lesion detection from CT data with internal sensitivity control

    NASA Astrophysics Data System (ADS)

    Wels, M.; Kelm, B. M.; Tsymbal, A.; Hammon, M.; Soza, G.; Sühling, M.; Cavallaro, A.; Comaniciu, D.

    2012-03-01

    Spinal bone lesion detection is a challenging and important task in cancer diagnosis and treatment monitoring. In this paper we present a method for fully-automatic osteolytic spinal bone lesion detection from 3D CT data. It is a multi-stage approach subsequently applying multiple discriminative models, i.e., multiple random forests, for lesion candidate detection and rejection to an input volume. For each detection stage an internal control mechanism ensures maintaining sensitivity on unseen true positive lesion candidates during training. This way a pre-defined target sensitivity score of the overall system can be taken into account at the time of model generation. For a lesion not only the center is detected but also, during post-processing, its spatial extension along the three spatial axes defined by the surrounding vertebral body's local coordinate system. Our method achieves a cross-validated sensitivity score of 75% and a mean false positive rate of 3.0 per volume on a data collection consisting of 34 patients with 105 osteolytic spinal bone lesions. The median sensitivity score is 86% at 2.0 false positives per volume.

  9. Higher Education Moderates the Effect of T2 Lesion Load and Third Ventricle Width on Cognition in Multiple Sclerosis

    PubMed Central

    Pinter, Daniela; Sumowski, James; DeLuca, John; Fazekas, Franz; Pichler, Alexander; Khalil, Michael; Langkammer, Christian; Fuchs, Siegrid; Enzinger, Christian

    2014-01-01

    Background Previous work suggested greater intellectual enrichment might moderate the negative impact of brain atrophy on cognition. This awaits confirmation in independent cohorts including investigation of the role of T2-lesion load (T2-LL), which is another important determinant of cognition in MS. We here thus aimed to test this cognitive reserve hypothesis by investigating whether educational attainment (EA) moderates the negative effects of both brain atrophy and T2-LL on cognitive function in a large sample of MS patients. Methods 137 patients participated in the study. Cognition was assessed by the “Brief Repeatable Battery of Neuropsychological Tests.” T2-LL, normalized brain volume (global volume loss) and third ventricle width (regional volume loss) served as MRI markers. Results Both T2-LL and atrophy predicted worse cognition, with a stronger effect of T2-LL. Higher EA (as assessed by years of education) also predicted better cognition. Interactions showed that the negative effects of T2-LL and regional brain atrophy were moderated by EA. Conclusions In a cohort with different stages of MS, higher EA attenuated the negative effects of white matter lesion burden and third ventricle width (suggestive of thalamic atrophy) on cognitive performance. Actively enhancing cognitive reserve might thus be a means to reduce or prevent cognitive problems in MS in parallel to disease modifying drugs. PMID:24475309

  10. Enhanced detection of dentinal lesions in OCT images using the RKT transformation

    NASA Astrophysics Data System (ADS)

    Kang, Hobin; Darling, Cynthia L.; Tom, Henry; Fried, Daniel

    2015-02-01

    Several studies have shown that optical coherence tomography (OCT) can be used to measure the remaining enamel thickness and detect the location of subsurface lesions hidden under the sound enamel. The purpose of this study was to develop algorithms to enhance the visibility of subsurface structures such as hidden occlusal lesions and the dentinal-enamel junction. Extracted teeth with natural occlusal lesions were imaged with OCT with and without added high index fluids. A Rotating Kernel Transformation (RKT) nonlinear image processing filter was applied to PS-OCT images to enhance the visibility of the subsurface lesions under the sound enamel. The filter significantly increased (P<0.05) the visibility of the subsurface lesions.

  11. Detection of blunt, sharp force and gunshot lesions on burnt remains: a cautionary note.

    PubMed

    Poppa, Pasquale; Porta, Davide; Gibelli, Daniele; Mazzucchi, Alessandra; Brandone, Alberto; Grandi, Marco; Cattaneo, Cristina

    2011-09-01

    The study of skin and bone lesions may give information concerning type and manner of production, but in burnt material modification of tissues by the high temperatures may considerably change the morphological characteristics of the lesions. This study aims at pointing out the effects of burning head of pigs with several types of lesions (blunt trauma, sharp force, and gunshot lesions) on soft tissues and bones, both from a morphological and chemical point of view. Results show that the charring process does not completely destroy signs of lesions on bones, which can often be recovered by cleaning bone surface from charred soft-tissue residues. Furthermore, neutron activation analysis test proved that antimony may be detectable also on gunshot entry wounds at the final stages of charring process.

  12. The prevalence, distribution and severity of detectable pathological lesions in badgers naturally infected with Mycobacterium bovis.

    PubMed

    Jenkins, H E; Morrison, W I; Cox, D R; Donnelly, C A; Johnston, W T; Bourne, F J; Clifton-Hadley, R S; Gettinby, G; McInerney, J P; Watkins, G H; Woodroffe, R

    2008-10-01

    The Randomized Badger Culling Trial (RBCT) began in 1998 to determine the impact of badger culling in controlling bovine tuberculosis in cattle. A total of 1166 badgers (14% of total) proactively culled during the RBCT were found to be tuberculous, offering a unique opportunity to study the pathology caused by Mycobacterium bovis in a large sample of badgers. Of these, 39% of adults (approximately 6% of all adults culled) had visible lesions (detectable at necropsy) of bovine tuberculosis; cubs had a lower prevalence of infection (9%) but a higher percentage of tuberculous cubs (55.5%) had visible lesions. Only approximately 1% of adult badgers had extensive, severe pathology. Tuberculous badgers with recorded bite wounds (approximately 5%) had a higher prevalence of visible lesions and a different distribution of lesions, suggesting transmission via bite wounds. However, the predominance of lesions in the respiratory tract indicates that most transmission occurs by the respiratory route.

  13. Detecting Secondary Caries Lesions: A Systematic Review and Meta-analysis.

    PubMed

    Brouwer, F; Askar, H; Paris, S; Schwendicke, F

    2016-02-01

    Secondary caries lesions are the main late complication of dental restorations, limiting their life span and generating costs by repeated reinterventions. Accurate detection of secondary lesions is crucial for estimating the true burden of the disease and allocating appropriate treatments. We aimed to assess the accuracy of detection methods for secondary caries lesions. Clinical or in vitro studies were included that investigated the accuracy of 5 detection methods--visual, tactile, radiography, laser fluorescence, quantitative light-induced fluorescence--of natural or artificially induced secondary lesions, as verified against an established reference test. Sensitivity, specificity, positive and negative likelihood ratios, as well as diagnostic odds ratios were calculated and publication bias assessed. From 1,179 screened studies, 23 were included. Most studies were performed in vitro, on permanent posterior teeth, and had high risk of bias or applicability concerns. Lesions were on proximal (14 studies) or other surfaces and adjacent to amalgam (16 studies) or tooth-colored materials. Visual (n = 11), radiographic (n = 13), and laser fluorescence detection (n = 8) had similar sensitivities (0.50 to 0.59) and specificities (0.78 to 0.83), with visual and laser fluorescence assessment being more accurate on nonproximal surfaces and adjacent to composites, respectively. Tactile assessment (n = 7) had low accuracy. Light-induced fluorescence (n = 3) was sensitive on nonproximal surfaces but had low specificities. Most analyses seemed to suffer from publication bias. Despite being a significant clinical and dental public health problem, detection of secondary caries lesions has been assessed by only a few studies with limited validity and applicability. Visual, radiographic and laser-fluorescence detection might be useful to detect secondary lesions. The validity of tactile assessment and quantitative light-induced fluorescence remains unclear at present. PMID

  14. Initial assessment of image quality for low-dose PET: evaluation of lesion detectability

    NASA Astrophysics Data System (ADS)

    Schaefferkoetter, Joshua D.; Yan, Jianhua; Townsend, David W.; Conti, Maurizio

    2015-07-01

    In the context of investigating the potential of low-dose PET imaging for screening applications, we developed methods to assess small lesion detectability as a function of the number of counts in the scan. We present here our methods and preliminary validation using tuberculosis cases. FDG-PET data from seventeen patients presenting diffuse hyper-metabolic lung lesions were selected for the study, to include a wide range of lesion sizes and contrasts. Reduced doses were simulated by randomly discarding events in the PET list mode, and ten realizations at each simulated dose were generated and reconstructed. The data were grouped into 9 categories determined by the number of included true events, from  >40 M to  <250 k counts. The images reconstructed from the original full statistical set were used to identify lung lesions, and each was, at every simulated dose, quantified by 6 parameters: lesion metabolic volume, lesion-to-background contrast, mean lesion tracer uptake, standard deviation of activity measurements (across realizations), lesion signal-to-noise ratio (SNR), and Hotelling observer SNR. Additionally, a lesion-detection task including 550 images was presented to several experienced image readers for qualitative assessment. Human observer performances were ranked using receiver operating characteristic analysis. The observer results were correlated with the lesion image measurements and used to train mathematical observer models. Absolute sensitivities and specificities of the human observers, as well as the area under the ROC curve, showed clustering and performance similarities among images produced from 5 million or greater counts. The results presented here are from a clinically realistic but highly constrained experiment, and more work is needed to validate these findings with a larger patient population.

  15. Detection of canine oral papillomavirus DNA in conjunctival epithelial hyperplastic lesions of three dogs.

    PubMed

    Brandes, K; Fritsche, J; Mueller, N; Koerschgen, B; Dierig, B; Strebelow, G; Teifke, J P

    2009-01-01

    Papillomavirus infections are responsible for plaques and papillomas in various locations on the skin and in mucous membranes. The aim of this report was to describe morphologic features of a viral pigmented conjunctival plaque and 2 conjunctival squamous papillomas in 3 dogs, and to investigate these lesions for the presence of papillomavirus DNA by polymerase chain reaction (PCR), DNA sequence analysis, and in situ hydridization (ISH). Histopathology revealed in all neoplasms various degrees of epithelial hyperplasia, acanthosis, and hyperkeratosis with koilocytosis. In all lesions E6, E7, and L1 gene fragments of canine oral papillomavirus (COPV) DNA were detected by PCR and sequencing analysis. ISH revealed COPV DNA in a highly specific pattern within nuclei of the hyperplastic epithelium. The presence of canine papillomavirus in ocular conjunctival plaques and papillomas suggests these benign lesions may have the potential for malignant transformation. This is the first time that the lambdapapillomavirus COPV has been detected in ocular epithelial hyperplastic lesions. PMID:19112112

  16. Immunohistochemical detection of papillomavirus structural antigens in animal hyperplastic and neoplastic epithelial lesions.

    PubMed

    Sironi, G; Caniatti, M; Scanziani, E

    1990-12-01

    One hundred and seventy-two hyperplastic and neoplastic epithelial lesions from 8 different mammalian and 1 avian species have been tested with an immunohistochemical technique to detect papillomavirus structural antigens. Selected lesions were diagnosed histologically as papilloma, fibropapilloma, equine sarcoid, squamous cell carcinoma, basalioma, epulis, keratoacanthoma, trichoepithelioma, pilomatrixoma, epidermal inclusion cyst, and hyperkeratotic or acanthotic epidermal lesions. Positive nuclear staining was detected in 14 out of 23 papillomas, 8 out of 32 fibropapillomas and in 1 out of 3 hyperplastic epidermal lesions. Positive samples were found in 5 of 8 mammalian species. Selected samples were also examined by transmission electron microscopy. In 4 samples papillomavirus was seen. In two other samples, negative with immunoperoxidase technique, papovavirus-like particles were observed.

  17. Optical configuration of pigmented lesion detection by frequency analysis of skin speckle patterns

    PubMed Central

    Bishitz, Yael; Ozana, Nisan; Schwarz, Ariel; Beiderman, Yevgeny; Garcia, Javier; Zalevsky, Zeev

    2016-01-01

    In this paper we present a novel approach of realizing a safe, simple, and inexpensive sensor applicable to pigmented lesions detection. The approach is based on temporal tracking of back-reflected secondary speckle patterns generated while illuminating the affected area with a laser and applying periodic pressure to the surface via a controlled vibration source. When applied to pigmented lesions, the technique is superior to visual examination in avoiding many false positives and resultant unnecessary biopsies. Applying a series of different vibration frequencies at the examined tissue and analyzing the 2-D time varying speckle patterns in response to the applied periodic pressure creates a unique signature for each and different pigmented lesion. Analyzing these signatures is the first step toward detection of malignant melanoma. In this paper we present preliminary experiments that show the validity of the developed sensor for the classification of pigmented lesions. PMID:27231603

  18. Display conditions and lesion detectability: effect of background light

    NASA Astrophysics Data System (ADS)

    Razavi, Mahmood; Hall, Theodore R.; Aberle, Denise R.; Hayrapetian, Alek S.; Loloyan, Mansur; Eldredge, Sandra L.

    1990-08-01

    We assessed the effect of high background light on observer performance for the detection of a variety of chest radiographic abnormalities. Five observers reviewed 66 digital hard copy chest images formatted to 1 1 x 14 inch size under two display conditions: 1) on a specially prepared 1 1 x 14 inch illuminated panel with no peripheral light and 2) on a standard viewing panel designed for 14 x 17 inch radiographs. The images contained one - or more of the following conditions: pneumothorax, interstitial disease, nodules, alveolar process, or no abnormality. The results of receiver operator characteristic analysis show that extraneous light does reduce observer performance and the detectability of nodules, interstitial disease.

  19. Superficial esophageal lesions detected by endoscopic ultrasound enhanced with submucosal edema

    PubMed Central

    Li, Jian-Jun; He, Long-Jun; Shan, Hong-Bo; Wang, Thomas D; Xiong, Huan; Chen, Li-Ming; Xu, Guo-Liang; Li, Xiao-Hai; Huang, Xin-Xin; Luo, Guang-Yu; Li, Yin; Zhang, Rong

    2013-01-01

    AIM: To determine if there is consistency between endoscopic ultrasound (EUS) findings and pathological results for detecting lesions of different depth in the esophageal mucosa. METHODS: A canine (Beagle) model was established in which lesions of different depths were created in the esophageal mucosa by thermal burning. Seventy-two hours later, these lesions and adjacent tissue in the esophagus were examined by EUS. EUS findings including infiltrating depth, strength of echogenicity and homogeneity were recorded. Dogs were sacrificed and tissue specimens were obtained. We then compared the EUS findings with the pathology reports. RESULTS: Thermal burns created at different power settings caused lesions of different depth in the esophageal mucosa. When the echo strength was shifted from high, medium, to low echogenicity, an increase in the infiltrating depth of the lesion was noted, which coincided with results of the pathology examination. Obvious submucosal edema visualized by EUS was also detected by pathology. Furthermore, because of the enhancement caused by the submucosal edema, the lesions invading into the submucosa were easily visualized by EUS. CONCLUSION: There is consistency between EUS findings and pathological results of esophageal lesions with different depths. Submucosal edema can serve as an ultrasonic contrast agent. PMID:24379628

  20. Combining CRF and multi-hypothesis detection for accurate lesion segmentation in breast sonograms.

    PubMed

    Hao, Zhihui; Wang, Qiang; Seong, Yeong Kyeong; Lee, Jong-Ha; Ren, Haibing; Kim, Ji-yeun

    2012-01-01

    The implementation of lesion segmentation for breast ultrasound image relies on several diagnostic rules on intensity, texture, etc. In this paper, we propose a novel algorithm to achieve a comprehensive decision upon these rules by incorporating image over-segmentation and lesion detection in a pairwise CRF model, rather than a term-by-term translation. Multiple detection hypotheses are used to propagate object-level cues to segments and a unified classifier is trained based on the concatenated features. The experimental results show that our algorithm can avoid the drawbacks of separate detection or bottom-up segmentation, and can deal with very complicated cases. PMID:23285589

  1. B-Spline Filtering for Automatic Detection of Calcification Lesions in Mammograms

    SciTech Connect

    Bueno, G.; Ruiz, M.; Sanchez, S

    2006-10-04

    Breast cancer continues to be an important health problem between women population. Early detection is the only way to improve breast cancer prognosis and significantly reduce women mortality. It is by using CAD systems that radiologist can improve their ability to detect, and classify lesions in mammograms. In this study the usefulness of using B-spline based on a gradient scheme and compared to wavelet and adaptative filtering has been investigated for calcification lesion detection and as part of CAD systems. The technique has been applied to different density tissues. A qualitative validation shows the success of the method.

  2. B-Spline Filtering for Automatic Detection of Calcification Lesions in Mammograms

    NASA Astrophysics Data System (ADS)

    Bueno, G.; Sánchez, S.; Ruiz, M.

    2006-10-01

    Breast cancer continues to be an important health problem between women population. Early detection is the only way to improve breast cancer prognosis and significantly reduce women mortality. It is by using CAD systems that radiologist can improve their ability to detect, and classify lesions in mammograms. In this study the usefulness of using B-spline based on a gradient scheme and compared to wavelet and adaptative filtering has been investigated for calcification lesion detection and as part of CAD systems. The technique has been applied to different density tissues. A qualitative validation shows the success of the method.

  3. Exploring sarcasm detection in amyotrophic lateral sclerosis using ecologically valid measures

    PubMed Central

    Staios, Mathew; Fisher, Fiona; Lindell, Annukka K.; Ong, Ben; Howe, Jim; Reardon, Katrina

    2013-01-01

    Amyotrophic lateral sclerosis (ALS) is a rapidly progressive condition involving degeneration of both upper and lower motor neurons. Recent research suggests that a proportion of persons with ALS show a profile similar to that of frontotemporal dementia (FTD), with this group of ALS patients exhibiting social cognitive deficits. Although social cognitive deficits have been partially explored in ALS, research has yet to investigate such changes using ecologically valid measures. Therefore, this study aimed to further characterize the scope of social cognitive and emotion recognition deficits in non-demented ALS patients using an ecologically valid measure of social cognition. A sample of 35 ALS patients and 30 age-and-education matched controls were assessed using the Addenbrooke's Cognitive Examination, the Brixton Spatial Anticipation Test, and The Awareness of Social Inference Test, where participants were required to discriminate between various emotions and decipher socially challenging scenarios enacted in video vignettes. Participants with ALS showed significant difficulties in recognizing both sarcastic and paradoxical sarcastic statements, but not sincere statements, when compared to controls. After controlling for executive difficulties, ALS patients still displayed significant difficulties on tasks that assessed their comprehension of both sarcastic and paradoxical sarcastic statements. The inability to read social cues and make social inferences has the potential to place significant strain on familial/interpersonal relationships in ALS. The findings of this study highlight the importance of employing a broader range of neuropsychological assessment tools to aid in early detection of frontal lobe impairment in non-demented ALS patients. PMID:23734113

  4. Developing Pulmonary Vasculopathy in Systemic Sclerosis, Detected with Non-Invasive Cardiopulmonary Exercise Testing

    PubMed Central

    Dumitrescu, Daniel; Oudiz, Ronald J.; Karpouzas, George; Hovanesyan, Arsen; Jayasinghe, Amali; Hansen, James E.; Rosenkranz, Stephan; Wasserman, Karlman

    2010-01-01

    Background Patients with systemic sclerosis (SSc) may develop exercise intolerance due to musculoskeletal involvement, restrictive lung disease, left ventricular dysfunction, or pulmonary vasculopathy (PV). The latter is particularly important since it may lead to lethal pulmonary arterial hypertension (PAH). We hypothesized that abnormalities during cardiopulmonary exercise testing (CPET) in patients with SSc can identify PV leading to overt PAH. Methods Thirty SSc patients from the Harbor-UCLA Rheumatology clinic, not clinically suspected of having significant pulmonary vascular disease, were referred for this prospective study. Resting pulmonary function and exercise gas exchange were assessed, including peakVO2, anaerobic threshold (AT), heart rate- VO2 relationship (O2-pulse), exercise breathing reserve and parameters of ventilation-perfusion mismatching, as evidenced by elevated ventilatory equivalent for CO2 (VE/VCO2) and reduced end-tidal pCO2 (PETCO2) at the AT. Results Gas exchange patterns were abnormal in 16 pts with specific cardiopulmonary disease physiology: Eleven patients had findings consistent with PV, while five had findings consistent with left-ventricular dysfunction (LVD). Although both groups had low peak VO2 and AT, a higher VE/VCO2 at AT and decreasing PETCO2 during early exercise distinguished PV from LVD. Conclusions Previously undiagnosed exercise impairments due to LVD or PV were common in our SSc patients. Cardiopulmonary exercise testing may help to differentiate and detect these disorders early in patients with SSc. PMID:21179195

  5. 4D numerical observer for lesion detection in respiratory-gated PET

    PubMed Central

    Lorsakul, Auranuch; Li, Quanzheng; Trott, Cathryn M.; Hoog, Christopher; Petibon, Yoann; Ouyang, Jinsong; Laine, Andrew F.; El Fakhri, Georges

    2014-01-01

    Purpose: Respiratory-gated positron emission tomography (PET)/computed tomography protocols reduce lesion smearing and improve lesion detection through a synchronized acquisition of emission data. However, an objective assessment of image quality of the improvement gained from respiratory-gated PET is mainly limited to a three-dimensional (3D) approach. This work proposes a 4D numerical observer that incorporates both spatial and temporal informations for detection tasks in pulmonary oncology. Methods: The authors propose a 4D numerical observer constructed with a 3D channelized Hotelling observer for the spatial domain followed by a Hotelling observer for the temporal domain. Realistic 18F-fluorodeoxyglucose activity distributions were simulated using a 4D extended cardiac torso anthropomorphic phantom including 12 spherical lesions at different anatomical locations (lower, upper, anterior, and posterior) within the lungs. Simulated data based on Monte Carlo simulation were obtained using geant4 application for tomographic emission (GATE). Fifty noise realizations of six respiratory-gated PET frames were simulated by GATE using a model of the Siemens Biograph mMR scanner geometry. PET sinograms of the thorax background and pulmonary lesions that were simulated separately were merged to generate different conditions of the lesions to the background (e.g., lesion contrast and motion). A conventional ordered subset expectation maximization (OSEM) reconstruction (5 iterations and 6 subsets) was used to obtain: (1) gated, (2) nongated, and (3) motion-corrected image volumes (a total of 3200 subimage volumes: 2400 gated, 400 nongated, and 400 motion-corrected). Lesion-detection signal-to-noise ratios (SNRs) were measured in different lesion-to-background contrast levels (3.5, 8.0, 9.0, and 20.0), lesion diameters (10.0, 13.0, and 16.0 mm), and respiratory motion displacements (17.6–31.3 mm). The proposed 4D numerical observer applied on multiple-gated images was

  6. 4D numerical observer for lesion detection in respiratory-gated PET

    SciTech Connect

    Lorsakul, Auranuch; Li, Quanzheng; Ouyang, Jinsong; El Fakhri, Georges; Trott, Cathryn M.; Hoog, Christopher; Petibon, Yoann; Laine, Andrew F.

    2014-10-15

    Purpose: Respiratory-gated positron emission tomography (PET)/computed tomography protocols reduce lesion smearing and improve lesion detection through a synchronized acquisition of emission data. However, an objective assessment of image quality of the improvement gained from respiratory-gated PET is mainly limited to a three-dimensional (3D) approach. This work proposes a 4D numerical observer that incorporates both spatial and temporal informations for detection tasks in pulmonary oncology. Methods: The authors propose a 4D numerical observer constructed with a 3D channelized Hotelling observer for the spatial domain followed by a Hotelling observer for the temporal domain. Realistic {sup 18}F-fluorodeoxyglucose activity distributions were simulated using a 4D extended cardiac torso anthropomorphic phantom including 12 spherical lesions at different anatomical locations (lower, upper, anterior, and posterior) within the lungs. Simulated data based on Monte Carlo simulation were obtained using GEANT4 application for tomographic emission (GATE). Fifty noise realizations of six respiratory-gated PET frames were simulated by GATE using a model of the Siemens Biograph mMR scanner geometry. PET sinograms of the thorax background and pulmonary lesions that were simulated separately were merged to generate different conditions of the lesions to the background (e.g., lesion contrast and motion). A conventional ordered subset expectation maximization (OSEM) reconstruction (5 iterations and 6 subsets) was used to obtain: (1) gated, (2) nongated, and (3) motion-corrected image volumes (a total of 3200 subimage volumes: 2400 gated, 400 nongated, and 400 motion-corrected). Lesion-detection signal-to-noise ratios (SNRs) were measured in different lesion-to-background contrast levels (3.5, 8.0, 9.0, and 20.0), lesion diameters (10.0, 13.0, and 16.0 mm), and respiratory motion displacements (17.6–31.3 mm). The proposed 4D numerical observer applied on multiple-gated images was

  7. Bright Retinal Lesions Detection using Colour Fundus Images Containing Reflective Features

    SciTech Connect

    Giancardo, Luca; Karnowski, Thomas Paul; Chaum, Edward; Meriaudeau, Fabrice; Tobin Jr, Kenneth William; Li, Yaquin

    2009-01-01

    In the last years the research community has developed many techniques to detect and diagnose diabetic retinopathy with retinal fundus images. This is a necessary step for the implementation of a large scale screening effort in rural areas where ophthalmologists are not available. In the United States of America, the incidence of diabetes is worryingly increasing among the young population. Retina fundus images of patients younger than 20 years old present a high amount of reflection due to the Nerve Fibre Layer (NFL), the younger the patient the more these reflections are visible. To our knowledge we are not aware of algorithms able to explicitly deal with this type of reflection artefact. This paper presents a technique to detect bright lesions also in patients with a high degree of reflective NFL. First, the candidate bright lesions are detected using image equalization and relatively simple histogram analysis. Then, a classifier is trained using texture descriptor (Multi-scale Local Binary Patterns) and other features in order to remove the false positives in the lesion detection. Finally, the area of the lesions is used to diagnose diabetic retinopathy. Our database consists of 33 images from a telemedicine network currently developed. When determining moderate to high diabetic retinopathy using the bright lesions detected the algorithm achieves a sensitivity of 100% at a specificity of 100% using hold-one-out testing.

  8. Temporal Characteristics of Radiologists' and Novices' Lesion Detection in Viewing Medical Images Presented Rapidly and Sequentially

    PubMed Central

    Nakashima, Ryoichi; Komori, Yuya; Maeda, Eriko; Yoshikawa, Takeharu; Yokosawa, Kazuhiko

    2016-01-01

    Although viewing multiple stacks of medical images presented on a display is a relatively new but useful medical task, little is known about this task. Particularly, it is unclear how radiologists search for lesions in this type of image reading. When viewing cluttered and dynamic displays, continuous motion itself does not capture attention. Thus, it is effective for the target detection that observers' attention is captured by the onset signal of a suddenly appearing target among the continuously moving distractors (i.e., a passive viewing strategy). This can be applied to stack viewing tasks, because lesions often show up as transient signals in medical images which are sequentially presented simulating a dynamic and smoothly transforming image progression of organs. However, it is unclear whether observers can detect a target when the target appears at the beginning of a sequential presentation where the global apparent motion onset signal (i.e., signal of the initiation of the apparent motion by sequential presentation) occurs. We investigated the ability of radiologists to detect lesions during such tasks by comparing the performances of radiologists and novices. Results show that overall performance of radiologists is better than novices. Furthermore, the temporal locations of lesions in CT image sequences, i.e., when a lesion appears in an image sequence, does not affect the performance of radiologists, whereas it does affect the performance of novices. Results indicate that novices have greater difficulty in detecting a lesion appearing early than late in the image sequence. We suggest that radiologists have other mechanisms to detect lesions in medical images with little attention which novices do not have. This ability is critically important when viewing rapid sequential presentations of multiple CT images, such as stack viewing tasks. PMID:27774080

  9. Automatic segmentation of lesions for the computer-assisted detection in fluorescence urology

    NASA Astrophysics Data System (ADS)

    Kage, Andreas; Legal, Wolfgang; Kelm, Peter; Simon, Jörg; Bergen, Tobias; Münzenmayer, Christian; Benz, Michaela

    2012-03-01

    Bladder cancer is one of the most common cancers in the western world. The diagnosis in Germany is based on the visual inspection of the bladder. This inspection performed with a cystoscope is a challenging task as some kinds of abnormal tissues do not differ much in their appearance from their surrounding healthy tissue. Fluorescence Cystoscopy has the potential to increase the detection rate. A liquid marker introduced into the bladder in advance of the inspection is concentrated in areas with high metabolism. Thus these areas appear as bright "glowing". Unfortunately, the fluorescence image contains besides the glowing of the suspicious lesions no more further visual information like for example the appearance of the blood vessels. A visual judgment of the lesion as well as a precise treatment has to be done using white light illumination. Thereby, the spatial information of the lesion provided by the fluorescence image has to be guessed by the clinical expert. This leads to a time consuming procedure due to many switches between the modalities and increases the risk of mistreatment. We introduce an automatic approach, which detects and segments any suspicious lesion in the fluorescence image automatically once the image was classified as a fluorescence image. The area of the contour of the detected lesion is transferred to the corresponding white light image and provide the clinical expert the spatial information of the lesion. The advantage of this approach is, that the clinical expert gets the spatial and the visual information of the lesion together in one image. This can save time and decrease the risk of an incomplete removal of a malign lesion.

  10. Detection and characterisation of papillomavirus in skin lesions of giraffe and sable antelope in South Africa.

    PubMed

    van Dyk, E; Bosman, A M; van Wilpe, E; Williams, J H; Bengis, R G; van Heerden, J; Venter, E H

    2011-06-01

    Papillomavirus was detected electron microscopically in cutaneous fibropapillomas of a giraffe (Giraffa camelopardalis) and a sable antelope (Hippotragus niger). The virus particles measured 45 nm in diameter. Histopathologically, the lesions showed histopathological features similar to those of equine sarcoid as well as positive immunoperoxidase-staining of tissue sections for papillomavirus antigen. Polymerase chain reaction (PCR) detected bovine papillomavirus (BPV) DNA. Bovine papillomavirus-1 was characterised by real-time PCR in the sable and giraffe, and cloning and sequencing of the PCR product revealed a similarity to BPV-1. As in the 1st giraffe, the lesions from a 2nd giraffe revealed locally malignant pleomorphism, possibly indicating the lesional end-point of papilloma infection. Neither virus particles nor positively staining papillomavirus antigen could be demonstrated in the 2nd giraffe but papillomavirus DNA was detected by real-time PCR which corresponded with BPV-1 and BPV-2. PMID:22135920

  11. Hierarchical detection of red lesions in retinal images by multiscale correlation filtering

    NASA Astrophysics Data System (ADS)

    Zhang, Bob; Wu, Xiangqian; You, Jane; Li, Qin; Karray, Fakhri

    2009-02-01

    This paper presents an approach to the computer aided diagnosis (CAD) of diabetic retinopathy (DR) -- a common and severe complication of long-term diabetes which damages the retina and cause blindness. Since red lesions are regarded as the first signs of DR, there has been extensive research on effective detection and localization of these abnormalities in retinal images. In contrast to existing algorithms, a new approach based on Multiscale Correlation Filtering (MSCF) and dynamic thresholding is developed. This consists of two levels, Red Lesion Candidate Detection (coarse level) and True Red Lesion Detection (fine level). The approach was evaluated using data from Retinopathy On-line Challenge (ROC) competition website and we conclude our method to be effective and efficient.

  12. Theoretical evaluation of the detectability of random lesions in bayesian emission reconstruction

    SciTech Connect

    Qi, Jinyi

    2003-05-01

    Detecting cancerous lesion is an important task in positron emission tomography (PET). Bayesian methods based on the maximum a posteriori principle (also called penalized maximum likelihood methods) have been developed to deal with the low signal to noise ratio in the emission data. Similar to the filter cut-off frequency in the filtered backprojection method, the prior parameters in Bayesian reconstruction control the resolution and noise trade-off and hence affect detectability of lesions in reconstructed images. Bayesian reconstructions are difficult to analyze because the resolution and noise properties are nonlinear and object-dependent. Most research has been based on Monte Carlo simulations, which are very time consuming. Building on the recent progress on the theoretical analysis of image properties of statistical reconstructions and the development of numerical observers, here we develop a theoretical approach for fast computation of lesion detectability in Bayesian reconstruction. The results can be used to choose the optimum hyperparameter for the maximum lesion detectability. New in this work is the use of theoretical expressions that explicitly model the statistical variation of the lesion and background without assuming that the object variation is (locally) stationary. The theoretical results are validated using Monte Carlo simulations. The comparisons show good agreement between the theoretical predications and the Monte Carlo results.

  13. Enhancing the detection of hidden occlusal caries lesions with OCT using high index liquids

    NASA Astrophysics Data System (ADS)

    Kang, Hobin; Darling, Cynthia L.; Fried, Daniel

    2014-02-01

    In a previous study, we investigated the influence of several high refractive index fluids on the performance of polarization sensitive optical coherence tomography (PS-OCT). That study showed that these liquids can increase the effective imaging depth and lesion contrast. Other in vitro and in vivo studies have shown that OCT can be used to show whether occlusal lesions have penetrated to the dentinal-enamel junction (DEJ) and spread laterally under the enamel. The purpose of this study was to determine if high index fluids can enhance the ability of OCT to detect hidden occlusal lesions and show if these lesions have penetrated through the enamel into the underlying dentin. Ten extracted teeth with occlusal lesions were imaged using OCT after the application of water, glycerol, BABB (33% Benzyl Alcohol + 67% Benzyl Benzoate) and a Cargille Liquid (Cedar Grove, NJ) (hydrogenated terphenyl 1- bromo-naphthalene) with a refractive index of 1.61. The intensity of the reflectance from the underlying lesion area for each sample was compared with the reflectance of the sound tooth surface for each fluid. The use of high index fluids significantly (P< 0.0001) increased the reflectivity of subsurface occlusal lesions under the surrounding sound enamel.

  14. Automated detection of remineralization in simulated enamel lesions with PS-OCT

    PubMed Central

    Lee, Robert C.; Darling, Cynthia L.; Fried, Daniel

    2014-01-01

    Previous in vitro and in vivo studies have demonstrated that polarization-sensitive optical coherence tomography (PS-OCT) can be used to nondestructively image the subsurface structure and measure the thickness of the highly mineralized transparent surface zone of caries lesions. There are structural differences between active lesions and arrested lesions, and the surface layer thickness may correlate with activity of the lesion. The purpose of this study was to develop a method that can be used to automatically detect and measure the thickness of the transparent surface layer in PS-OCT images. Automated methods of analysis were used to measure the thickness of the transparent layer and the depth of the bovine enamel lesions produced using simulated caries models that emulate demineralization in the mouth. The transparent layer thickness measured with PS-OCT correlated well with polarization light microscopy (PLM) measurements of all regions (r2=0.9213). This study demonstrates that PS-OCT can automatically detect and measure thickness of the transparent layer formed due to remineralization in simulated caries lesions. PMID:25075267

  15. Automated detection of remineralization in simulated enamel lesions with PS-OCT

    NASA Astrophysics Data System (ADS)

    Lee, Robert C.; Darling, Cynthia L.; Fried, Daniel

    2014-02-01

    Previous in vitro and in vivo studies have demonstrated that polarization-sensitive optical coherence tomography (PS-OCT) can be used to nondestructively image the subsurface structure and measure the thickness of the highly mineralized transparent surface zone of caries lesions. There are structural differences between active lesions and arrested lesions, and the surface layer thickness may correlate with activity of the lesion. The purpose of this study was to develop a method that can be used to automatically detect and measure the thickness of the transparent surface layer in PS-OCT images. Automated methods of analysis were used to measure the thickness of the transparent layer and the depth of the bovine enamel lesions produced using simulated caries models that emulate demineralization in the mouth. The transparent layer thickness measured with PS-OCT correlated well with polarization light microscopy (PLM) measurements of all regions (r2=0.9213). This study demonstrates that PS-OCT can automatically detect and measure thickness of the transparent layer formed due to remineralization in simulated caries lesions.

  16. CT of multiple sclerosis: reassessment of delayed scanning with high doses of contrast material

    SciTech Connect

    Spiegel, S.M.; Vinuela, F.; Fox, A.J.; Pelz, D.M.

    1985-09-01

    A prospective study involving 87 patients was carried out to evaluate the necessity for a high dose of contrast material in addition to delayed computed tomographic (CT) scanning for optimal detection of the lesions of multiple sclerosis in the brain. In patients with either clinically definite multiple sclerosis or laboratory-supported definite multiple sclerosis, CT scans were obtained with a uniform protocol. Lesions consistent with multiple sclerosis were demonstrated on the second scan in 54 patients. In 36 of these 54 patients, the high-dose delayed scan added information. These results are quite similar to those of a previous study from this institution using different patients, in whom the second scan was obtained immediately after the bolus injection of contrast material containing 40 g of organically bound iodine. The lack of real difference in the results of the two studies indicate that the increased dose, not just the delay in scanning, is necessary for a proper study.

  17. Impact of breast structure on lesion detection in breast tomosynthesis, a simulation study.

    PubMed

    Kiarashi, Nooshin; Nolte, Loren W; Lo, Joseph Y; Segars, W Paul; Ghate, Sujata V; Solomon, Justin B; Samei, Ehsan

    2016-07-01

    This study aims to characterize the effect of background tissue density and heterogeneity on the detection of irregular masses in breast tomosynthesis, while demonstrating the capability of the sophisticated tools that can be used in the design, implementation, and performance analysis of virtual clinical trials (VCTs). Twenty breast phantoms from the extended cardiac-torso (XCAT) family, generated based on dedicated breast computed tomography of human subjects, were used to extract a total of 2173 volumes of interest (VOIs) from simulated tomosynthesis images. Five different lesions, modeled after human subject tomosynthesis images, were embedded in the breasts and combined with the lesion absent condition yielded a total of [Formula: see text] VOIs. Effects of background tissue density and heterogeneity on the detection of the lesions were studied by implementing a composite hypothesis signal detection paradigm with location known exactly, lesion known exactly or statistically, and background known statistically. Using the area under the receiver operating characteristic curve, detection performance deteriorated as density was increased, yielding findings consistent with clinical studies. A human observer study was performed on a subset of the simulated tomosynthesis images, confirming the detection performance trends with respect to density and serving as a validation of the implemented detector. Performance of the implemented detector varied substantially across the 20 breasts. Furthermore, background tissue density and heterogeneity affected the log-likelihood ratio test statistic differently under lesion absent and lesion present conditions. Therefore, considering background tissue variability in tissue models can change the outcomes of a VCT and is hence of crucial importance. The XCAT breast phantoms have the potential to address this concern by offering realistic modeling of background tissue variability based on a wide range of human subjects, comprising

  18. Guidelines on the clinical use for the detection of neutralizing antibodies (NAbs) to IFN beta in multiple sclerosis therapy: report from the Italian Multiple Sclerosis Study group.

    PubMed

    Bertolotto, Antonio; Capobianco, Marco; Amato, Maria Pia; Capello, Elisabetta; Capra, Ruggero; Centonze, Diego; Di Ioia, Maria; Gallo, Antonio; Grimaldi, Luigi; Imberti, Luisa; Lugaresi, Alessandra; Mancinelli, Chiara; Marrosu, Maria Giovanna; Moiola, Lucia; Montanari, Enrico; Romano, Silvia; Musu, Luigina; Paolicelli, Damiano; Patti, Francesco; Pozzilli, Carlo; Rossi, Silvia; Salvetti, Marco; Tedeschi, Gioachino; Tola, Maria Rosaria; Trojano, Maria; Troiano, Maria; Zaffaroni, Mauro; Malucchi, Simona

    2014-02-01

    Interferon beta (IFNβ) was the first specific disease-modifying treatment licensed for relapsing-remitting multiple sclerosis, and is still one of the most commonly prescribed treatments. A strong body of evidence supports the effectiveness of IFNβ preparations in reducing the annual relapse rate, magnetic resonance (MRI) disease activity and disease progression. However, the development of binding/neutralizing antibodies (BAbs/NAbs) during treatment negatively affects clinical and MRI outcomes. Therefore, guidelines for the clinical use for the detection of NAbs in MS may result in better treatment of these patients. In October 2012, a panel of Italian neurologists from 17 MS clinics convened in Milan to review and discuss data on NAbs and their clinical relevance in the treatment of MS. In this paper, we report the panel's recommendations for the use of IFNβ Nabs detection in the early identification of IFNβ non-responsiveness and the management of patients on IFNβ treatment in Italy, according to a model of therapeutically appropriate care.

  19. Density-based parallel skin lesion border detection with webCL

    PubMed Central

    2015-01-01

    Background Dermoscopy is a highly effective and noninvasive imaging technique used in diagnosis of melanoma and other pigmented skin lesions. Many aspects of the lesion under consideration are defined in relation to the lesion border. This makes border detection one of the most important steps in dermoscopic image analysis. In current practice, dermatologists often delineate borders through a hand drawn representation based upon visual inspection. Due to the subjective nature of this technique, intra- and inter-observer variations are common. Because of this, the automated assessment of lesion borders in dermoscopic images has become an important area of study. Methods Fast density based skin lesion border detection method has been implemented in parallel with a new parallel technology called WebCL. WebCL utilizes client side computing capabilities to use available hardware resources such as multi cores and GPUs. Developed WebCL-parallel density based skin lesion border detection method runs efficiently from internet browsers. Results Previous research indicates that one of the highest accuracy rates can be achieved using density based clustering techniques for skin lesion border detection. While these algorithms do have unfavorable time complexities, this effect could be mitigated when implemented in parallel. In this study, density based clustering technique for skin lesion border detection is parallelized and redesigned to run very efficiently on the heterogeneous platforms (e.g. tablets, SmartPhones, multi-core CPUs, GPUs, and fully-integrated Accelerated Processing Units) by transforming the technique into a series of independent concurrent operations. Heterogeneous computing is adopted to support accessibility, portability and multi-device use in the clinical settings. For this, we used WebCL, an emerging technology that enables a HTML5 Web browser to execute code in parallel for heterogeneous platforms. We depicted WebCL and our parallel algorithm design. In

  20. Brain MRI segmentation and lesion detection using generalized Gaussian and Rician modeling

    NASA Astrophysics Data System (ADS)

    Wu, Xuqiang; Bricq, Stéphanie; Collet, Christophe

    2011-03-01

    In this paper we propose a mixed noise modeling so as to segment the brain and to detect lesion. Indeed, accurate segmentation of multimodal (T1, T2 and Flair) brain MR images is of great interest for many brain disorders but requires to efficiently manage multivariate correlated noise between available modalities. We addressed this problem in1 by proposing an entirely unsupervised segmentation scheme, taking into account multivariate Gaussian noise, imaging artifacts,intrinsic tissue variation and partial volume effects in a Bayesian framework. Nevertheless, tissue classification remains a challenging task especially when one addresses the lesion detection during segmentation process2 as we did. In order to improve brain segmentation into White and Gray Matter (resp. WM and GM) and cerebro-spinal fluid (CSF), we propose to fit a Rician (RC) density distribution for CSF whereas Generalized Gaussian (GG) models are used to fit the likelihood between model and data corresponding to WM and GM. In this way, we present in this paper promising results showing that in a multimodal segmentation-detection scheme, this model fits better with the data and increases lesion detection rate. One of the main challenges consists in being able to take into account various pdf (Gaussian and non- Gaussian) for correlated noise between modalities and to show that lesion-detection is then clearly improved, probably because non-Gaussian noise better fits to the physic of MRI image acquisition.

  1. Detection of early carious lesions using contrast enhancement with coherent light scattering (speckle imaging)

    NASA Astrophysics Data System (ADS)

    Deana, A. M.; Jesus, S. H. C.; Koshoji, N. H.; Bussadori, S. K.; Oliveira, M. T.

    2013-07-01

    Currently, dental caries still represent one of the chronic diseases with the highest prevalence and present in most countries. The interaction between light and teeth (absorption, scattering and fluorescence) is intrinsically connected to the constitution of the dental tissue. Decay induced mineral loss introduces a shift in the optical properties of the affected tissue; therefore, study of these properties may produce novel techniques aimed at the early diagnosis of carious lesions. Based on the optical properties of the enamel, we demonstrate the application of first-order spatial statistics in laser speckle imaging, allowing the detection of carious lesions in their early stages. A highlight of this noninvasive, non-destructive, real time and cost effective approach is that it allows a dentist to detect a lesion even in the absence of biofilm or moisture.

  2. Exercise stress echocardiography for detection of pulmonary arterial hypertension in a patient with systemic sclerosis.

    PubMed

    Cotrim, Carlos; Cordeiro, Ana; Loureiro, Maria José; Santos, Maria José; Simões, Otília; Cordeiro, Pedro; da Silva, J Canas; Carrageta, Manuel

    2006-02-01

    The authors report the case of a 57-year-old patient, diagnosed with systemic sclerosis 16 years ago. She had been followed in the rheumatology outpatient clinic since 2003 and complained of marked fatigue and dyspnea on exertion. In addition to full medical evaluation, she also underwent standard Doppler echocardiography at rest, which was unremarkable, and exercise stress echocardiography. In the latter examination, she was diagnosed with pulmonary arterial hypertension, later confirmed during right heart catheterization. The authors discuss the potential value of this methodology for the study of patients with systemic sclerosis.

  3. Importance of Defect Detectability in Positron Emission Tomography Imaging of Abdominal Lesions

    PubMed Central

    Yamashita, Shozo; Yokoyama, Kunihiko; Onoguchi, Masahisa; Yamamoto, Haruki; Nakaichi, Tetsu; Tsuji, Shiro; Nakajima, Kenichi

    2015-01-01

    Objective(s): This study was designed to assess defect detectability in positron emission tomography (PET) imaging of abdominal lesions. Methods: A National Electrical Manufactures Association International Electrotechnical Commission phantom was used. The simulated abdominal lesion was scanned for 10 min using dynamic list-mode acquisition method. Images, acquired with scan duration of 1-10 min, were reconstructed using VUE point HD and a 4.7 mm full-width at half-maximum (FWHM) Gaussian filter. Iteration-subset combinations of 2-16 and 2-32 were used. Visual and physical analyses were performed using the acquired images. To sequentially evaluate defect detectability in clinical settings, we examined two middle-aged male subjects. One had a liver cyst (approximately 10 mm in diameter) and the other suffered from pancreatic cancer with an inner defect region (approximately 9 mm in diameter). Results: In the phantom study, at least 6 and 3 min acquisition durations were required to visualize 10 and 13 mm defect spheres, respectively. On the other hand, spheres with diameters ≥17 mm could be detected even if the acquisition duration was only 1 min. The visual scores were significantly correlated with background (BG) variability. In clinical settings, the liver cyst could be slightly visualized with an acquisition duration of 6 min, although image quality was suboptimal. For pancreatic cancer, the acquisition duration of 3 min was insufficient to clearly describe the defect region. Conclusion: The improvement of BG variability is the most important factor for enhancing lesion detection. Our clinical scan duration (3 min/bed) may not be suitable for the detection of small lesions or accurate tumor delineation since an acquisition duration of at least 6 min is required to visualize 10 mm lesions, regardless of reconstruction parameters. Improvements in defect detectability are important for radiation treatment planning and accurate PET-based diagnosis. PMID:27408887

  4. Lesion detection in magnetic resonance brain images by hyperspectral imaging algorithms

    NASA Astrophysics Data System (ADS)

    Xue, Bai; Wang, Lin; Li, Hsiao-Chi; Chen, Hsian Min; Chang, Chein-I.

    2016-05-01

    Magnetic Resonance (MR) images can be considered as multispectral images so that MR imaging can be processed by multispectral imaging techniques such as maximum likelihood classification. Unfortunately, most multispectral imaging techniques are not particularly designed for target detection. On the other hand, hyperspectral imaging is primarily developed to address subpixel detection, mixed pixel classification for which multispectral imaging is generally not effective. This paper takes advantages of hyperspectral imaging techniques to develop target detection algorithms to find lesions in MR brain images. Since MR images are collected by only three image sequences, T1, T2 and PD, if a hyperspectral imaging technique is used to process MR images it suffers from the issue of insufficient dimensionality. To address this issue, two approaches to nonlinear dimensionality expansion are proposed, nonlinear correlation expansion and nonlinear band ratio expansion. Once dimensionality is expanded hyperspectral imaging algorithms are readily applied. The hyperspectral detection algorithm to be investigated for lesion detection in MR brain is the well-known subpixel target detection algorithm, called Constrained Energy Minimization (CEM). In order to demonstrate the effectiveness of proposed CEM in lesion detection, synthetic images provided by BrainWeb are used for experiments.

  5. Remote optical configuration of pigmented lesion detection and diagnosis of bone fractures

    NASA Astrophysics Data System (ADS)

    Ozana, Nisan; Bishitz, Yael; Beiderman, Yevgeny; Garcia, Javier; Zalevsky, Zeev; Schwarz, Ariel

    2016-02-01

    In this paper we present a novel approach of realizing a safe, simple, and inexpensive sensor applicable to bone fractures and pigmented lesions detection. The approach is based on temporal tracking of back-reflected secondary speckle pattern generated while illuminating the affected area with a laser and applying periodic pressure to the surface via a controlled vibration. The use of such a concept was already demonstrated for non-contact monitoring of various bio-medical parameters such as heart rate, blood pulse pressure, concentration of alcohol and glucose in the blood stream and intraocular pressure. The presented technique is a safe and effective method of detecting bone fractures in populations at risk. When applied to pigmented lesions, the technique is superior to visual examination in avoiding many false positives and resultant unnecessary biopsies. Applying a series of different vibration frequencies at the examined tissue and analyzing the 2-D speckle pattern trajectory in response to the applied periodic pressure creates a unique signature for each and different pigmented lesion. Analyzing these signatures is the first step toward detection of malignant melanoma. In this paper we present preliminary experiments that show the validity of the developed sensor for both applications: the detection of damaged bones as well as the classification of pigmented lesions.

  6. Improving lesion detectability in PET imaging with a penalized likelihood reconstruction algorithm

    NASA Astrophysics Data System (ADS)

    Wangerin, Kristen A.; Ahn, Sangtae; Ross, Steven G.; Kinahan, Paul E.; Manjeshwar, Ravindra M.

    2015-03-01

    Ordered Subset Expectation Maximization (OSEM) is currently the most widely used image reconstruction algorithm for clinical PET. However, OSEM does not necessarily provide optimal image quality, and a number of alternative algorithms have been explored. We have recently shown that a penalized likelihood image reconstruction algorithm using the relative difference penalty, block sequential regularized expectation maximization (BSREM), achieves more accurate lesion quantitation than OSEM, and importantly, maintains acceptable visual image quality in clinical wholebody PET. The goal of this work was to evaluate lesion detectability with BSREM versus OSEM. We performed a twoalternative forced choice study using 81 patient datasets with lesions of varying contrast inserted into the liver and lung. At matched imaging noise, BSREM and OSEM showed equivalent detectability in the lungs, and BSREM outperformed OSEM in the liver. These results suggest that BSREM provides not only improved quantitation and clinically acceptable visual image quality as previously shown but also improved lesion detectability compared to OSEM. We then modeled this detectability study, applying both nonprewhitening (NPW) and channelized Hotelling (CHO) model observers to the reconstructed images. The CHO model observer showed good agreement with the human observers, suggesting that we can apply this model to future studies with varying simulation and reconstruction parameters.

  7. Automatic ultrasonic breast lesions detection using support vector machine based algorithm

    NASA Astrophysics Data System (ADS)

    Yeh, Chih-Kuang; Miao, Shan-Jung; Fan, Wei-Che; Chen, Yung-Sheng

    2007-03-01

    It is difficult to automatically detect tumors and extract lesion boundaries in ultrasound images due to the variance in shape, the interference from speckle noise, and the low contrast between objects and background. The enhancement of ultrasonic image becomes a significant task before performing lesion classification, which was usually done with manual delineation of the tumor boundaries in the previous works. In this study, a linear support vector machine (SVM) based algorithm is proposed for ultrasound breast image training and classification. Then a disk expansion algorithm is applied for automatically detecting lesions boundary. A set of sub-images including smooth and irregular boundaries in tumor objects and those in speckle-noised background are trained by the SVM algorithm to produce an optimal classification function. Based on this classification model, each pixel within an ultrasound image is classified into either object or background oriented pixel. This enhanced binary image can highlight the object and suppress the speckle noise; and it can be regarded as degraded paint character (DPC) image containing closure noise, which is well known in perceptual organization of psychology. An effective scheme of removing closure noise using iterative disk expansion method has been successfully demonstrated in our previous works. The boundary detection of ultrasonic breast lesions can be further equivalent to the removal of speckle noise. By applying the disk expansion method to the binary image, we can obtain a significant radius-based image where the radius for each pixel represents the corresponding disk covering the specific object information. Finally, a signal transmission process is used for searching the complete breast lesion region and thus the desired lesion boundary can be effectively and automatically determined. Our algorithm can be performed iteratively until all desired objects are detected. Simulations and clinical images were introduced to

  8. Potential of hybrid adaptive filtering in inflammatory lesion detection from capsule endoscopy images

    PubMed Central

    Charisis, Vasileios S; Hadjileontiadis, Leontios J

    2016-01-01

    A new feature extraction technique for the detection of lesions created from mucosal inflammations in Crohn’s disease, based on wireless capsule endoscopy (WCE) images processing is presented here. More specifically, a novel filtering process, namely Hybrid Adaptive Filtering (HAF), was developed for efficient extraction of lesion-related structural/textural characteristics from WCE images, by employing Genetic Algorithms to the Curvelet-based representation of images. Additionally, Differential Lacunarity (DLac) analysis was applied for feature extraction from the HAF-filtered images. The resulted scheme, namely HAF-DLac, incorporates support vector machines for robust lesion recognition performance. For the training and testing of HAF-DLac, an 800-image database was used, acquired from 13 patients who undertook WCE examinations, where the abnormal cases were grouped into mild and severe, according to the severity of the depicted lesion, for a more extensive evaluation of the performance. Experimental results, along with comparison with other related efforts, have shown that the HAF-DLac approach evidently outperforms them in the field of WCE image analysis for automated lesion detection, providing higher classification results, up to 93.8% (accuracy), 95.2% (sensitivity), 92.4% (specificity) and 92.6% (precision). The promising performance of HAF-DLac paves the way for a complete computer-aided diagnosis system that could support physicians’ clinical practice.

  9. Effect of glatiramer acetate three-times weekly on the evolution of new, active multiple sclerosis lesions into T1-hypointense "black holes": a post hoc magnetic resonance imaging analysis.

    PubMed

    Zivadinov, Robert; Dwyer, Michael; Barkay, Hadas; Steinerman, Joshua R; Knappertz, Volker; Khan, Omar

    2015-03-01

    Conversion of active lesions to black holes has been associated with disability progression in subjects with relapsing-remitting multiple sclerosis (RRMS) and represents a complementary approach to evaluating clinical efficacy. The objective of this study was to assess the conversion of new active magnetic resonance imaging (MRI) lesions, identified 6 months after initiating treatment with glatiramer acetate 40 mg/mL three-times weekly (GA40) or placebo, to T1-hypointense black holes in subjects with RRMS. Subjects received GA40 (n = 943) or placebo (n = 461) for 12 months. MRI was obtained at baseline and Months 6 and 12. New lesions were defined as either gadolinium-enhancing T1 or new T2 lesions at Month 6 that were not present at baseline. The adjusted mean numbers of new active lesions at Month 6 converting to black holes at Month 12 were analyzed using a negative binomial model; adjusted proportions of new active lesions at Month 6 converting to black holes at Month 12 were analyzed using a logistic regression model. Of 1,292 subjects with complete MRI data, 433 (50.3 %) GA-treated and 247 (57.2 %) placebo-treated subjects developed new lesions at Month 6. Compared with placebo, GA40 significantly reduced the mean number (0.31 versus 0.45; P = .0258) and proportion (15.8 versus 19.6 %; P = .006) of new lesions converting to black holes. GA significantly reduced conversion of new active lesions to black holes, highlighting the ability of GA40 to prevent tissue damage in RRMS. PMID:25542295

  10. Effect of glatiramer acetate three-times weekly on the evolution of new, active multiple sclerosis lesions into T1-hypointense "black holes": a post hoc magnetic resonance imaging analysis.

    PubMed

    Zivadinov, Robert; Dwyer, Michael; Barkay, Hadas; Steinerman, Joshua R; Knappertz, Volker; Khan, Omar

    2015-03-01

    Conversion of active lesions to black holes has been associated with disability progression in subjects with relapsing-remitting multiple sclerosis (RRMS) and represents a complementary approach to evaluating clinical efficacy. The objective of this study was to assess the conversion of new active magnetic resonance imaging (MRI) lesions, identified 6 months after initiating treatment with glatiramer acetate 40 mg/mL three-times weekly (GA40) or placebo, to T1-hypointense black holes in subjects with RRMS. Subjects received GA40 (n = 943) or placebo (n = 461) for 12 months. MRI was obtained at baseline and Months 6 and 12. New lesions were defined as either gadolinium-enhancing T1 or new T2 lesions at Month 6 that were not present at baseline. The adjusted mean numbers of new active lesions at Month 6 converting to black holes at Month 12 were analyzed using a negative binomial model; adjusted proportions of new active lesions at Month 6 converting to black holes at Month 12 were analyzed using a logistic regression model. Of 1,292 subjects with complete MRI data, 433 (50.3 %) GA-treated and 247 (57.2 %) placebo-treated subjects developed new lesions at Month 6. Compared with placebo, GA40 significantly reduced the mean number (0.31 versus 0.45; P = .0258) and proportion (15.8 versus 19.6 %; P = .006) of new lesions converting to black holes. GA significantly reduced conversion of new active lesions to black holes, highlighting the ability of GA40 to prevent tissue damage in RRMS.

  11. A clinically applicable approach for detecting spontaneous action potential spikes in amyotrophic lateral sclerosis with a linear electrode array.

    PubMed

    Jahanmiri-Nezhad, Faezeh; Li, Xiaoyan; Barkhaus, Paul E; Rymer, William Z; Zhou, Ping

    2014-02-01

    Examination of spontaneous muscle activity is an important part of the routine electromyogram (EMG) in assessing neuromuscular diseases. The EMG is specifically valuable as a diagnostic test in supporting the diagnosis of amyotrophic lateral sclerosis. High-density surface EMG is a relatively new technique that has until now been used in research but has the potential for clinical application. This study presents a simple high-density surface EMG method for automatic detection of spontaneous action potentials from surface electrode array recordings of patients with amyotrophic lateral sclerosis. To reduce computational complexity while maintaining useful information from the electrode array recording, the multichannel high-density surface EMG was transferred to single-dimensional data by calculating the maximum difference across all channels of the electrode array. A spike detection threshold was then set in the single-dimensional domain to identify the firing times of each spontaneous action potential spike, whereas a spike extraction threshold was used to define the onset and offset of the spontaneous spikes. These data were used to extract the spontaneous spike waveforms from the electrode array EMG. A database of detected spontaneous spikes was thus obtained, including their waveforms, on all channels along with their corresponding firing times. This newly developed method makes use of the information from different channels of the electrode array EMG recording. It also has the primary feature of being simple and fast in implementation, with convenient parameter adjustment and user-computer interaction. Hence, it has good possibilities for clinical application.

  12. Role of saccadic analysis in the diagnosis of multiple sclerosis in the era of magnetic resonance imaging.

    PubMed Central

    Tedeschi, G; Allocca, S; Di Costanzo, A; Diano, A; Bonavita, V

    1989-01-01

    Magnetic resonance imaging (MRI) has recently been recognised as the most sensitive method with which to detect clinically silent lesions in patients affected by multiple sclerosis. Visually guided horizontal saccadic eye movements (SEM) were studied, together with MRI, in 57 multiple sclerosis patients. A very similar sensitivity was found for both MRI (78.2%) and SEM analysis (76.3%). Significant associations between peak saccadic velocity and brain stem signs and between saccadic latency and visual signs were observed. PMID:2795066

  13. A gradient in cortical pathology in multiple sclerosis by in vivo quantitative 7 T imaging.

    PubMed

    Mainero, Caterina; Louapre, Céline; Govindarajan, Sindhuja T; Giannì, Costanza; Nielsen, A Scott; Cohen-Adad, Julien; Sloane, Jacob; Kinkel, Revere P

    2015-04-01

    We used a surface-based analysis of T2* relaxation rates at 7 T magnetic resonance imaging, which allows sampling quantitative T2* throughout the cortical width, to map in vivo the spatial distribution of intracortical pathology in multiple sclerosis. Ultra-high resolution quantitative T2* maps were obtained in 10 subjects with clinically isolated syndrome/early multiple sclerosis (≤ 3 years disease duration), 18 subjects with relapsing-remitting multiple sclerosis (≥ 4 years disease duration), 13 subjects with secondary progressive multiple sclerosis, and in 17 age-matched healthy controls. Quantitative T2* maps were registered to anatomical cortical surfaces for sampling T2* at 25%, 50% and 75% depth from the pial surface. Differences in laminar quantitative T2* between each patient group and controls were assessed using general linear model (P < 0.05 corrected for multiple comparisons). In all 41 multiple sclerosis cases, we tested for associations between laminar quantitative T2*, neurological disability, Multiple Sclerosis Severity Score, cortical thickness, and white matter lesions. In patients, we measured, T2* in intracortical lesions and in the intracortical portion of leukocortical lesions visually detected on 7 T scans. Cortical lesional T2* was compared with patients' normal-appearing cortical grey matter T2* (paired t-test) and with mean cortical T2* in controls (linear regression using age as nuisance factor). Subjects with multiple sclerosis exhibited relative to controls, independent from cortical thickness, significantly increased T2*, consistent with cortical myelin and iron loss. In early disease, T2* changes were focal and mainly confined at 25% depth, and in cortical sulci. In later disease stages T2* changes involved deeper cortical laminae, multiple cortical areas and gyri. In patients, T2* in intracortical and leukocortical lesions was increased compared with normal-appearing cortical grey matter (P < 10(-10) and P < 10(-7)), and mean

  14. A new total body scanning system for automatic change detection in multiple pigmented skin lesions.

    PubMed

    Korotkov, Konstantin; Quintana, Josep; Puig, Susana; Malvehy, Josep; Garcia, Rafael

    2015-01-01

    The detection of newly appearing and changing pigmented skin lesions (PSLs) is essential for timely diagnosis of cutaneous melanoma. Total body skin examination (TBSE) procedures, currently practiced for this purpose, can be extremely time-consuming for patients with numerous lesions. In addition, these procedures are prone to subjectivity when selecting PSLs for baseline image comparison, increasing the risk of missing a developing cancer. To address this issue, we propose a new photogrammetry-based total body scanning system allowing for skin surface image acquisition using cross-polarized light. Equipped with 21 high-resolution cameras and a turntable, this scanner automatically acquires a set of overlapping images, covering 85%-90% of the patient's skin surface. These images are used for the automated mapping of PSLs and their change estimation between explorations. The maps produced relate images of individual lesions with their locations on the patient's body, solving the body-to-image and image-to-image correspondence problem in TBSEs. Currently, the scanner is limited to patients with sparse body hair and, for a complete skin examination, the scalp, palms, soles and inner arms should be photographed manually. The initial tests of the scanner showed that it can be successfully applied for automated mapping and temporal monitoring of multiple lesions: PSLs relevant for follow-up were repeatedly mapped in several explorations. Moreover, during the baseline image comparison, all lesions with artificially induced changes were correctly identified as "evolved." PMID:25222947

  15. Immunohistochemical myofiber typing and high-resolution myofibrillar lesion detection in LR white embedded muscle

    NASA Technical Reports Server (NTRS)

    Thompson, J. L.; Vijayan, K.; Riley, D. A.

    2000-01-01

    We have developed a method of fixing, embedding, sectioning, and staining that allows high-resolution detection of myofibrillar structure and myosin immunocytochemical muscle fiber typing in serial semithin sections of LR White plastic embedded muscle at the light microscopic level. Traditional approaches, such as cryostat sections, permit fiber typing, but small myofibrillar lesions (1-3 sarcomeres) are difficult to detect because of section thickness. Semithin sections of hydrophobic resins do not stain well either histochemically or immunocytochemically. Electron microscopy can resolve lesions and discriminate fiber types based on morphology, but the sampling area is small. Our goal was to develop a rapid method for defining both fiber type and high-resolution primary myofibrillar lesion damage. Mild fixation (1-4% paraformaldehyde, 0. 05-0.1% glutaraldehyde) and embedment in a hydrophilic resin (LR White) were used. Myofibrillar structure was extremely well preserved at the light microscopic (LM) level, and lesions could be readily resolved in Toluidine blue stained 500-nm sections. Fiber type was defined by LM immunomyosin staining of serial plastic semithin sections, which demonstrated reciprocal staining patterns for "fast (Sigma M4276) and "total" (skeletal muscle) myosins (Sigma M7523). Copyright 2000 Wiley-Liss, Inc.

  16. Nakagami imaging for detecting thermal lesions induced by high-intensity focused ultrasound in tissue.

    PubMed

    Rangraz, Parisa; Behnam, Hamid; Tavakkoli, Jahan

    2014-01-01

    High-intensity focused ultrasound induces focalized tissue coagulation by increasing the tissue temperature in a tight focal region. Several methods have been proposed to monitor high-intensity focused ultrasound-induced thermal lesions. Currently, ultrasound imaging techniques that are clinically used for monitoring high-intensity focused ultrasound treatment are standard pulse-echo B-mode ultrasound imaging, ultrasound temperature estimation, and elastography-based methods. On the contrary, the efficacy of two-dimensional Nakagami parametric imaging based on the distribution of the ultrasound backscattered signals to quantify properties of soft tissue has recently been evaluated. In this study, ultrasound radio frequency echo signals from ex vivo tissue samples were acquired before and after high-intensity focused ultrasound exposures and then their Nakagami parameter and scaling parameter of Nakagami distribution were estimated. These parameters were used to detect high-intensity focused ultrasound-induced thermal lesions. Also, the effects of changing the acoustic power of the high-intensity focused ultrasound transducer on the Nakagami parameters were studied. The results obtained suggest that the Nakagami distribution's scaling and Nakagami parameters can effectively be used to detect high-intensity focused ultrasound-induced thermal lesions in tissue ex vivo. These parameters can also be used to understand the degree of change in tissue caused by high-intensity focused ultrasound exposures, which could be interpreted as a measure of degree of variability in scatterer concentration in various parts of the high-intensity focused ultrasound lesion. PMID:24264647

  17. Spinal cord MRI in multiple sclerosis with multicoil arrays: a comparison between fast spin echo and fast FLAIR.

    PubMed Central

    Filippi, M; Yousry, T A; Alkadhi, H; Stehling, M; Horsfield, M A; Voltz, R

    1996-01-01

    OBJECTIVES: To compare the sensitivity of fast spin echo (FSE) and of fast fluid attenuated inversion recovery (fast FLAIR) in detecting spinal cord lesions in multiple sclerosis. METHODS: With a 1.5 Tesla machine and a multicoil receiver array, FSE images (with two different pixel sizes) and fast FLAIR images of the spinal cord were obtained from 13 patients with multiple sclerosis. RESULTS: Twenty three lesions (10 cervical, 12 thoracic, and one lumbar) were found in seven patients (54%) using FSE with the larger pixel size. Seventeen lesions (seven cervical and 10 thoracic) were detected in the same seven patients using FSE with smaller pixel size. Nine lesions (five cervical and four thoracic) were found using fast FLAIR in six patients (46%). All the lesions found using fast FLAIR were detected using the other two techniques and all the lesions detected by FSE with smaller pixel size were detected using FSE and greater pixel size. CONCLUSION: Fast FLAIR sequences detect substantially fewer cord lesions in patients with multiple sclerosis. Images PMID:8971115

  18. What proportions of focal liver lesions detected by unenhanced ultrasound are inconclusive?

    PubMed Central

    Willits, Iain; Burn, Julie; Cole, Helen; Hoare, Tim

    2014-01-01

    In August 2012, the National Institute for Health and Care Excellence produced positive diagnostics guidance on the ultrasound contrast agent SonoVue®, but recommended further research involving an estimation of the proportion of unenhanced ultrasound scans reporting, but not characterising, focal liver lesions, particularly in cirrhotic livers. Patient records from the Radiology Information System of an acute hospital trust were progressively filtered based on categorical fields and keywords in the free text reports, to obtain ultrasound records including the liver that were appropriate for manual analysis. In total, 21,731 records referred from general practice or out-patient clinics were analysed. Patients described as having cirrhosis were analysed as a subgroup. After automatic exclusion of records considered likely to be negative, 5812 records were manually read and categorised as focal liver lesion inconclusive, benign or malignant. In the general practice cohort of 9175 records, 746 reported the presence of one or more focal liver lesions, with 18.4% (95% CI 15.7% to 21.3%) of these records mentioning an inconclusive focal liver lesion. In the out-patient cohort of 12,556 records, 1437 reported one or more focal liver lesions, and 29.4% (95% CI 26.9% to 32.0%) of these were inconclusive. Cirrhosis was reported in 10.8% of the out-patient scans that also reported a focal liver lesion, and 47.4% (95% CI 39.3% to 55.6%) of these scans had an inconclusive focal liver lesion, compared with 27.3% (95% CI 24.9% to 29.8%) that were inconclusive in non-cirrhotic livers (odds ratio 2.4; 95% CI 1.7 to 3.4). This retrospective study indicates that unenhanced ultrasound scans, in which a focal liver lesion is detected, are frequently inconclusive, with the probability of an inconclusive scan being greater in out-patient than general practice referrals. Inconclusive focal liver lesions were also reported in greater proportions of cirrhotic than non-cirrhotic livers. The

  19. Oral precancerous lesions: Problems of early detection and oral cancer prevention

    NASA Astrophysics Data System (ADS)

    Gileva, Olga S.; Libik, Tatiana V.; Danilov, Konstantin V.

    2016-08-01

    The study presents the results of the research in the structure, local and systemic risk factors, peculiarities of the clinical manifestation, and quality of primary diagnosis of precancerous oral mucosa lesions (OMLs). In the study a wide range of OMLs and high (25.4%) proportion of oral precancerous lesions (OPLs) in their structure was indicated. The high percentage of different diagnostic errors and the lack of oncological awareness of dental practitioners, as well as the sharp necessity of inclusion of precancer/cancer early detection techniques into their daily practice were noted. The effectiveness of chemilumenescence system of early OPLs and oral cancer detection was demonstrated, the prospects of infrared thermography as a diagnostic tool were also discussed.

  20. Coordinating Center: Molecular and Cellular Findings of Screen-Detected Lesions | Division of Cancer Prevention

    Cancer.gov

    DESCRIPTION (provided by applicant): The Molecular and Cellular Characterization of Screen‐Detected Lesions ‐ Coordinating Center and Data Management Group will provide support for the participating studies responding to RFA CA14‐10. The coordinating center supports three main domains: network coordination, statistical support and computational analysis and protocol development and database support. Support for communication is provided through an interactive web portal, management of conference calls, and meeting support. |

  1. Noninvasive Real-Time Automated Skin Lesion Analysis System for Melanoma Early Detection and Prevention

    PubMed Central

    Abuzaghleh, Omar; Barkana, Buket D.

    2015-01-01

    Melanoma spreads through metastasis, and therefore, it has been proved to be very fatal. Statistical evidence has revealed that the majority of deaths resulting from skin cancer are as a result of melanoma. Further investigations have shown that the survival rates in patients depend on the stage of the cancer; early detection and intervention of melanoma implicate higher chances of cure. Clinical diagnosis and prognosis of melanoma are challenging, since the processes are prone to misdiagnosis and inaccuracies due to doctors’ subjectivity. Malignant melanomas are asymmetrical, have irregular borders, notched edges, and color variations, so analyzing the shape, color, and texture of the skin lesion is important for the early detection and prevention of melanoma. This paper proposes the two major components of a noninvasive real-time automated skin lesion analysis system for the early detection and prevention of melanoma. The first component is a real-time alert to help users prevent skinburn caused by sunlight; a novel equation to compute the time for skin to burn is thereby introduced. The second component is an automated image analysis module, which contains image acquisition, hair detection and exclusion, lesion segmentation, feature extraction, and classification. The proposed system uses PH2 Dermoscopy image database from Pedro Hispano Hospital for the development and testing purposes. The image database contains a total of 200 dermoscopy images of lesions, including benign, atypical, and melanoma cases. The experimental results show that the proposed system is efficient, achieving classification of the benign, atypical, and melanoma images with accuracy of 96.3%, 95.7%, and 97.5%, respectively. PMID:27170906

  2. Early-Stage White Matter Lesions Detected by Multispectral MRI Segmentation Predict Progressive Cognitive Decline

    PubMed Central

    Jokinen, Hanna; Gonçalves, Nicolau; Vigário, Ricardo; Lipsanen, Jari; Fazekas, Franz; Schmidt, Reinhold; Barkhof, Frederik; Madureira, Sofia; Verdelho, Ana; Inzitari, Domenico; Pantoni, Leonardo; Erkinjuntti, Timo

    2015-01-01

    White matter lesions (WML) are the main brain imaging surrogate of cerebral small-vessel disease. A new MRI tissue segmentation method, based on a discriminative clustering approach without explicit model-based added prior, detects partial WML volumes, likely representing very early-stage changes in normal-appearing brain tissue. This study investigated how the different stages of WML, from a “pre-visible” stage to fully developed lesions, predict future cognitive decline. MRI scans of 78 subjects, aged 65–84 years, from the Leukoaraiosis and Disability (LADIS) study were analyzed using a self-supervised multispectral segmentation algorithm to identify tissue types and partial WML volumes. Each lesion voxel was classified as having a small (33%), intermediate (66%), or high (100%) proportion of lesion tissue. The subjects were evaluated with detailed clinical and neuropsychological assessments at baseline and at three annual follow-up visits. We found that voxels with small partial WML predicted lower executive function compound scores at baseline, and steeper decline of executive scores in follow-up, independently of the demographics and the conventionally estimated hyperintensity volume on fluid-attenuated inversion recovery images. The intermediate and fully developed lesions were related to impairments in multiple cognitive domains including executive functions, processing speed, memory, and global cognitive function. In conclusion, early-stage partial WML, still too faint to be clearly detectable on conventional MRI, already predict executive dysfunction and progressive cognitive decline regardless of the conventionally evaluated WML load. These findings advance early recognition of small vessel disease and incipient vascular cognitive impairment. PMID:26696814

  3. Early-Stage White Matter Lesions Detected by Multispectral MRI Segmentation Predict Progressive Cognitive Decline.

    PubMed

    Jokinen, Hanna; Gonçalves, Nicolau; Vigário, Ricardo; Lipsanen, Jari; Fazekas, Franz; Schmidt, Reinhold; Barkhof, Frederik; Madureira, Sofia; Verdelho, Ana; Inzitari, Domenico; Pantoni, Leonardo; Erkinjuntti, Timo

    2015-01-01

    White matter lesions (WML) are the main brain imaging surrogate of cerebral small-vessel disease. A new MRI tissue segmentation method, based on a discriminative clustering approach without explicit model-based added prior, detects partial WML volumes, likely representing very early-stage changes in normal-appearing brain tissue. This study investigated how the different stages of WML, from a "pre-visible" stage to fully developed lesions, predict future cognitive decline. MRI scans of 78 subjects, aged 65-84 years, from the Leukoaraiosis and Disability (LADIS) study were analyzed using a self-supervised multispectral segmentation algorithm to identify tissue types and partial WML volumes. Each lesion voxel was classified as having a small (33%), intermediate (66%), or high (100%) proportion of lesion tissue. The subjects were evaluated with detailed clinical and neuropsychological assessments at baseline and at three annual follow-up visits. We found that voxels with small partial WML predicted lower executive function compound scores at baseline, and steeper decline of executive scores in follow-up, independently of the demographics and the conventionally estimated hyperintensity volume on fluid-attenuated inversion recovery images. The intermediate and fully developed lesions were related to impairments in multiple cognitive domains including executive functions, processing speed, memory, and global cognitive function. In conclusion, early-stage partial WML, still too faint to be clearly detectable on conventional MRI, already predict executive dysfunction and progressive cognitive decline regardless of the conventionally evaluated WML load. These findings advance early recognition of small vessel disease and incipient vascular cognitive impairment. PMID:26696814

  4. Detection of questionable occlusal carious lesions using an electrical bioimpedance method with fractional electrical model.

    PubMed

    Morais, A P; Pino, A V; Souza, M N

    2016-08-01

    This in vitro study evaluated the diagnostic performance of an alternative electric bioimpedance spectroscopy technique (BIS-STEP) detect questionable occlusal carious lesions. Six specialists carried out the visual (V), radiography (R), and combined (VR) exams of 57 sound or non-cavitated occlusal carious lesion teeth classifying the occlusal surfaces in sound surface (H), enamel caries (EC), and dentinal caries (DC). Measurements were based on the current response to a step voltage excitation (BIS-STEP). A fractional electrical model was used to predict the current response in the time domain and to estimate the model parameters: Rs and Rp (resistive parameters), and C and α (fractional parameters). Histological analysis showed caries prevalence of 33.3% being 15.8% hidden caries. Combined examination obtained the best traditional diagnostic results with specificity = 59.0%, sensitivity = 70.9%, and accuracy = 60.8%. There were statistically significant differences in bioimpedance parameters between the H and EC groups (p = 0.016) and between the H and DC groups (Rs, p = 0.006; Rp, p = 0.022, and α, p = 0.041). Using a suitable threshold for the Rs, we obtained specificity = 60.7%, sensitivity = 77.9%, accuracy = 73.2%, and 100% of detection for deep lesions. It can be concluded that BIS-STEP method could be an important tool to improve the detection and management of occlusal non-cavitated primary caries and pigmented sites. PMID:27587136

  5. Detection of questionable occlusal carious lesions using an electrical bioimpedance method with fractional electrical model

    NASA Astrophysics Data System (ADS)

    Morais, A. P.; Pino, A. V.; Souza, M. N.

    2016-08-01

    This in vitro study evaluated the diagnostic performance of an alternative electric bioimpedance spectroscopy technique (BIS-STEP) detect questionable occlusal carious lesions. Six specialists carried out the visual (V), radiography (R), and combined (VR) exams of 57 sound or non-cavitated occlusal carious lesion teeth classifying the occlusal surfaces in sound surface (H), enamel caries (EC), and dentinal caries (DC). Measurements were based on the current response to a step voltage excitation (BIS-STEP). A fractional electrical model was used to predict the current response in the time domain and to estimate the model parameters: Rs and Rp (resistive parameters), and C and α (fractional parameters). Histological analysis showed caries prevalence of 33.3% being 15.8% hidden caries. Combined examination obtained the best traditional diagnostic results with specificity = 59.0%, sensitivity = 70.9%, and accuracy = 60.8%. There were statistically significant differences in bioimpedance parameters between the H and EC groups (p = 0.016) and between the H and DC groups (Rs, p = 0.006; Rp, p = 0.022, and α, p = 0.041). Using a suitable threshold for the Rs, we obtained specificity = 60.7%, sensitivity = 77.9%, accuracy = 73.2%, and 100% of detection for deep lesions. It can be concluded that BIS-STEP method could be an important tool to improve the detection and management of occlusal non-cavitated primary caries and pigmented sites.

  6. Evaluation of lesion detectability and crosstalk correction methods in dual radionuclide imaging

    SciTech Connect

    Ivanovic, M.; Esser, P.D.; Weber, D.A.

    1994-05-01

    Crosstalk components (XC) present in one or both energy windows (EWs) in dual radionuclide images can influence the detectability of cold defects and overestimate areas of hyperperfusion. Changes in lesion contrast due to the presence of crosstalk photons and correction methods were evaluated for combinations of radionuclides. Monte Carlo simulations of SPECT and planar imaging of a brain phantom containing 10 lesions ranging in size from 1 to 12 cm{sup 2} were run for Tc-99m, Xe-133, Tl-201 and I-123. Simulations of the gray and white matter compartments and lesions were run individually to allow greater flexibility in evaluating different radionuclide uptake distributions. Simulations of image acquisition at 15 EWs, corresponding to the baseline settings and EWs commonly used for imaging all four radionuclides, were recorded for each radionuclide. The system energy resolution (ER) was set at 1% intervals between 6 and 14%. XCs were calculated for: (1) Tc and I with 4:1 activity ratio (AR) of Tc/I; (2) Tc and Tl with a 5:1 AR and (3) Tc and Xe with a 2:1 and 4:1 AR. Cold defects of 10 to 60% with Xe, Tl and I were seen as 3 to 45% defects due to XC from Tc when similar distribution and defect size were assumed for both radionuclides. Large changes in lesion contrast were observed when multiple lesions with increased (hyperperfused regions) and decreased activity were used in the same study especially if cold lesions on Xe, Tl and I images, appear as regions with increased activity uptake on the Tc study. Image contrast improved when images recorded in the 100-110 keV EW were used to estimate and correct for Tc XC in the Xe- and Tl-studies; 10-60% defects were seen as defect of 6-55%. The study shows that large changes in lesion contrast and detectability due to XC can be corrected using a third EW in dual radionuclide imaging of Tc-Xe and Tc-Tl.

  7. The development of a disease oriented eFolder for multiple sclerosis decision support

    NASA Astrophysics Data System (ADS)

    Ma, Kevin; Jacobs, Colin; Fernandez, James; Amezcua, Lilyana; Liu, Brent

    2010-03-01

    Multiple sclerosis (MS) is a demyelinating disease of the central nervous system. The chronic nature of MS necessitates multiple MRI studies to track disease progression. Currently, MRI assessment of multiple sclerosis requires manual lesion measurement and yields an estimate of lesion volume and change that is highly variable and user-dependent. In the setting of a longitudinal study, disease trends and changes become difficult to extrapolate from the lesions. In addition, it is difficult to establish a correlation between these imaged lesions and clinical factors such as treatment course. To address these clinical needs, an MS specific e-Folder for decision support in the evaluation and assessment of MS has been developed. An e-Folder is a disease-centric electronic medical record in contrast to a patient-centric electronic health record. Along with an MS lesion computer aided detection (CAD) package for lesion load, location, and volume, clinical parameters such as patient demographics, disease history, clinical course, and treatment history are incorporated to make the e-Folder comprehensive. With the integration of MRI studies together with related clinical data and informatics tools designed for monitoring multiple sclerosis, it provides a platform to improve the detection of treatment response in patients with MS. The design and deployment of MS e-Folder aims to standardize MS lesion data and disease progression to aid in decision making and MS-related research.

  8. Multiple Sclerosis

    MedlinePlus

    Multiple sclerosis (MS) is a nervous system disease that affects your brain and spinal cord. It damages the ... attacks healthy cells in your body by mistake. Multiple sclerosis affects women more than men. It often begins ...

  9. Genetic imbalances in precursor lesions of endometrial cancer detected by comparative genomic hybridization.

    PubMed

    Kiechle, M; Hinrichs, M; Jacobsen, A; Lüttges, J; Pfisterer, J; Kommoss, F; Arnold, N

    2000-06-01

    Endometrial hyperplasia is regarded as a precursor lesion of endometrioid adenocarcinomas of the endometrium. The genetic events involved in the multistep process from normal endometrial glandular tissue to invasive endometrial carcinomas are primarily unknown. We chose endometrial hyperplasia as a model for identifying chromosomal aberrations occurring during carcinogenesis. Comparative genomic hybridization (CGH) was performed on 47 formalin-fixed, paraffin-embedded specimens of endometrial hyperplasia using the microdissection technique to increase the number of tumor cells in the samples and reduce contamination from normal cells. CGH analysis revealed that 24 out of 47 (51%) samples had detectable chromosomal imbalances, whereas 23 (49%) were in a genetically balanced state. The incidence of aberrant CGH profiles tended to parallel dysplasia grade, ranging from 22% aberrant profiles in simple hyperplasia to 67% in complex hyperplasia with atypia. The most frequent imbalances were 1p, 16p, and 20q underrepresentations and 4q overrepresentations. Copy number changes in 1p were more frequent in atypical complex hyperplasia than in complex lesions without atypical cells or simple lesions (42% versus 20% and 0%). Our results show that endometrial hyperplasia reveals recurrent chromosomal imbalances which tend to increase with the presence of atypical cells. The most frequent aberrations in endometrial cancer, 1q and 8q overrepresentations, are not present or are rare in its precursor lesions. This analysis provides evidence that tumorigenesis proceeds through the accumulation of a series of genetic alterations and suggests a stepwise mode of tumorigenesis. PMID:10854205

  10. [Use of magnetic resonance imaging in the diagnosis and prognosis of multiple sclerosis].

    PubMed

    Zivadinov, Robert; Sepcić, Juraj

    2006-01-01

    Multiple sclerosis is an autoimmune disease characterized by demyelination and axonal loss. Conventional magnetic resonance imaging allows the demonstration of spatial and temporal dissemination of multiple sclerosis lesions earlier than is possible from clinical assessments. A variety of conventional magnetic resonance imaging protocols, in conjunction with clinical assessment, are now routinely used to increase the accuracy of diagnosis and long-term prognosis of multiple sclerosis. T2-weighted hyperintense lesions are related primarily to increased water content and thus cannot distinguish between inflammation, edema, demyelination, Wallerian degeneration, and axonal loss, whereas the contrast gadolinium-enhanced lesions on T1-weighted images reflect increased blood-brain barrier permeability associated with active inflammatory activity. Conventional magnetic resonance imaging metrics are not sufficiently sensitive to detect invisible brain damage in the normal appearing brain tissue, and they do not show a reliable correlation with clinical measures of disability. However, numerous studies showed that they can improve accuracy in the diagnosis and prognosis of multiple sclerosis. Recently, non-conventional magnetic resonance imaging techniques have been introduced to increase the accuracy of diagnosis and prognosis of multiple sclerosis. Several studies have used brain atrophy, T1-hypointense lesion volume, magnetization transfer imaging, diffusion-weighted imaging and magnetic resonance spectroscopy to test whether the extent and severity of tissue loss in lesions and in normal appearing gray and white matter at the time of clinically isolated syndrome may have diagnostic and prognostic value. These magnetic resonance imaging techniques represent a powerful tool to non-invasively study different pathological substrates of lesions and microscopic tissue changes. Additional short- and long-term prospective studies are requested to establish their value in the

  11. Cronobacter sakazakii DNA Detection in Cerebrospinal Fluid of a Patient with Amyotrophic Lateral Sclerosis Mimic Syndrome.

    PubMed

    Piombo, Marianna; Chiarello, Daniela; Corbetto, Marzia; Di Pino, Giovanni; Dicuonzo, Giordano; Angeletti, Silvia; Riva, Elisabetta; De Florio, Lucia; Capone, Fioravante; Di Lazzaro, Vincenzo

    2015-01-01

    A 45-year-old male noticed progressive weakness of the right lower limb with gait disturbance. Over the following months, motor deficits worsened, spreading to the right upper limb. Electromyography showed active denervation in the upper and lower limb muscles. A diagnosis of amyotrophic lateral sclerosis (ALS) was made. About 2 years after symptom onset, gradual improvement occurred. Cerebrospinal fluid analysis performed about 3 years after the beginning of symptoms identified Cronobacter sakazakii. Since no other possible causes were identified, we suggest that an almost completely reversible ALS-like syndrome had been triggered by Cronobacter infection in our immunocompetent patient. PMID:26955334

  12. Multiple Sclerosis

    MedlinePlus

    ... Awards Enhancing Diversity Find People About NINDS NINDS Multiple Sclerosis Information Page Condensed from Multiple Sclerosis: Hope Through ... en Español Additional resources from MedlinePlus What is Multiple Sclerosis? An unpredictable disease of the central nervous system, ...

  13. Frequent Detection of Pancreatic Lesions in Asymptomatic High-Risk Individuals

    PubMed Central

    Canto, Marcia Irene; Hruban, Ralph H.; Fishman, Elliot K.; Kamel, Ihab R.; Schulick, Richard; Zhang, Zhe; Topazian, Mark; Takahashi, Naoki; Fletcher, Joel; Petersen, Gloria; Klein, Alison P.; Axilbund, Jennifer; Griffin, Constance; Syngal, Sapna; Saltzman, John R.; Mortele, Koenraad J.; Lee, Jeffrey; Tamm, Eric; Vikram, Raghunandan; Bhosale, Priya; Margolis, Daniel; Farrell, James; Goggins, Michael

    2012-01-01

    BACKGROUND & AIMS The risk of pancreatic cancer is increased in patients with a strong family history of pancreatic cancer or a predisposing germline mutation. Screening can detect curable, non-invasive pancreatic neoplasms, but the optimal imaging approach is not known. We determined the baseline prevalence and characteristics of pancreatic abnormalities using 3 imaging tests to screen asymptomatic, high-risk individuals (HRI). METHODS We screened 225 asymptomatic adult HRI at 5 academic US medical centers once, using computed tomography (CT), magnetic resonance imaging (MRI), and endoscopic ultrasonography (EUS). We compared results in a blinded, independent fashion. RESULTS Ninety-two of 216 HRI (42%) were found to have at least 1 pancreatic mass (84 cystic, 3 solid) or a dilated pancreatic duct (n=5) by any of the imaging modalities. Fifty-one of the 84 HRI with a cyst (60.7%) had multiple lesions, typically small (mean 0.55 cm, range 2–39 mm), in multiple locations. The prevalence of pancreatic lesions increased with age; they were detected in 14% of subjects <50 years old, 34% of subjects 50–59 years old, and 53% of subjects 60–69 years old (P<.0001). CT, MRI, and EUS detected a pancreatic abnormality in 11%, 33.3%, and 42.6% of the HRI, respectively. Among these abnormalities, proven or suspected neoplasms were identified in 85 HRI (82 intraductal papillary mucinous neoplasms [IPMN] and 3 pancreatic endocrine tumors). Three of 5 HRI who underwent pancreatic resection had high-grade dysplasia in <3 cm IPMNs and in multiple intraepithelial neoplasias. CONCLUSIONS Screening of asymptomatic HRI frequently detects small pancreatic cysts, including curable, non-invasive high-grade neoplasms. EUS and MRI detect pancreatic lesions better than CT. PMID:22245846

  14. Detection of intrathecal immunoglobulin G synthesis by capillary isoelectric focusing immunoassay in oligoclonal band negative multiple sclerosis.

    PubMed

    Halbgebauer, Steffen; Huss, André; Buttmann, Mathias; Steinacker, Petra; Oeckl, Patrick; Brecht, Isabel; Weishaupt, Andreas; Tumani, Hayrettin; Otto, Markus

    2016-05-01

    Oligoclonal immunoglobulin G bands (OCBs) restricted to the cerebrospinal fluid indicate intrathecal inflammation. Using isoelectric focusing and immunoblotting, they are detected in about 95 % of patients with clinically definite multiple sclerosis (MS). To elucidate whether in the remaining 5 % OCBs are truly absent or alternatively missed due to insufficient sensitivity of the routine measurement, we employed a new, highly sensitive nanoscale method for OCB detection. Capillary isoelectric focusing followed by immunological detection served to analyze OCBs in 33 well-characterized OCB-negative and 10 OCB-positive MS patients as well as in 100 OCB-negative control patients with non-inflammatory neurological diseases and 30 OCB-positive control patients with inflammatory neurological diseases. We detected intrathecal immunoglobulin G production in 10 out of 33 MS patients (30 %), initially diagnosed as being OCB-negative, and in all 10 OCB-positive MS patients, but in only 3 out of 100 non-inflammatory neurological controls (3 %) and in 29 of 30 inflammatory neurological controls (97 %). At least about one-third of MS patients without intrathecal immunoglobulin G synthesis according to standard methods are OCB-positive. Advanced methods for OCB detection may increase the analytical sensitivity for detecting OCB in patients with MS who are OCB-negative according to current routine methods.

  15. Fast approach to evaluate map reconstruction for lesion detection and localization

    SciTech Connect

    Qi, Jinyi; Huesman, Ronald H.

    2004-02-01

    Lesion detection is an important task in emission tomography. Localization ROC (LROC) studies are often used to analyze the lesion detection and localization performance. Most researchers rely on Monte Carlo reconstruction samples to obtain LROC curves, which can be very time-consuming for iterative algorithms. In this paper we develop a fast approach to obtain LROC curves that does not require Monte Carlo reconstructions. We use a channelized Hotelling observer model to search for lesions, and the results can be easily extended to other numerical observers. We theoretically analyzed the mean and covariance of the observer output. Assuming the observer outputs are multivariate Gaussian random variables, an LROC curve can be directly generated by integrating the conditional probability density functions. The high-dimensional integrals are calculated using a Monte Carlo method. The proposed approach is very fast because no iterative reconstruction is involved. Computer simulations show that the results of the proposed method match well with those obtained using the tradition LROC analysis.

  16. In vivo light scattering for the detection of cancerous and precancerous lesions of the cervix

    SciTech Connect

    Mourant, Judith R

    2008-01-01

    A noninvasive optical diagnostic system for detection of cancerous and precancerous lesions of the cervix was evaluated in vivo. The optical system included a fiber-optic probe designed to measure polarized and unpolarized light transport properties of a small volume of tissue. An algorithm for diagnosing tissue based on the optical measurements was developed that used four optical properties, three of which were related to light scattering properties and the fourth of which was related to hemoglobin concentration. A sensitivity of {approx}77% and specificities in the mid 60% range were obtained for separating high grade squamous intraepithelial lesions and cancer from other pathologies and normal tissue. The use of different cross-validation methods in algorithm development is analyzed, and the relative difficulties of diagnosing certain pathologies are assessed. Furthermore, the robustness of the optical system for use by different doctors and to changes in fiber-optic probe are also assessed, and potential improvements in the optical system are discussed.

  17. Electroconvulsive Therapy in Multiple Sclerosis.

    PubMed

    Steen, Katie; Narang, Puneet; Lippmann, Steven

    2015-01-01

    We performed a literature search regarding the safety and efficacy of electroconvulsive therapy in patients with multiple sclerosis and comorbid psychiatric symptoms. Literature review was conducted via PubMed databases. Of the cases we reviewed, most subjects with multiple sclerosis reported significant psychiatric symptom relief, with only a handful reporting neurologic deterioration. There was some evidence that active white matter lesions may be predictive of neurologic deterioration when electroconvulsive therapy is used in patients with multiple sclerosis. A brief description of the pathophysiology and effects of depression in patients with multiple sclerosis is also provided. Although no clinical recommendations or meaningful conclusions can be drawn without further investigation, the literature suggests that electroconvulsive therapy for treatment of psychiatric illnesses in patients with multiple sclerosis is safe and efficacious.

  18. Time-resolved optical mammography between 637 and 985 nm: clinical study on the detection and identification of breast lesions

    NASA Astrophysics Data System (ADS)

    Taroni, Paola; Torricelli, Alessandro; Spinelli, Lorenzo; Pifferi, Antonio; Arpaia, Francesco; Danesini, Gianmaria; Cubeddu, Rinaldo

    2005-06-01

    The first time-resolved optical mammograph operating beyond 900 nm was tested in a retrospective clinical study involving 194 patients with malignant and benign lesions, to investigate the diagnostic potential for the detection and characterization of breast lesions. For the first part of the study (101 patients with 114 lesions), the system was operated at 683, 785, 913 and 975 nm. Subsequently, to improve the spectral content of optical images, the number of wavelengths was increased (up to 7) and the spectral range was extended (637-985 nm). Late gated intensity and scattering images provide sensitivity to tissue composition (oxy- and deoxyhaemoglobin, water and lipids) and physiology (total haemoglobin content and oxygen saturation), as well as to structural changes. Tumours are typically identified because of the strong blood absorption at short wavelengths (637-685 nm), while cysts are characterized by low scattering, leading to a detection rate of approximately 80% for both lesion types, when detection is required in both cranio-caudal and oblique views. The detection rate for other benign lesions, such as fibroadenomas, is presently much lower (<40%). The effectiveness of the technique in localizing and identifying different lesion types was analysed as a function of various parameters (lesion size, compressed breast thickness, age, body mass index, breast parenchymal pattern). The possibility that physiologic changes due to the development of a malignant lesion could affect the entire breast was investigated. The capacity to assess the density of breast based on the average scattering properties was also tested.

  19. Diagnostic tests for the detection of human papillomavirus-associated cervical lesions.

    PubMed

    Reuschenbach, Miriam; von Knebel Doeberitz, Magnus

    2013-01-01

    Current diagnostic approaches for primary cervical cancer screening, work-up of equivocal or positive screening results or follow- up after treatment of precancerous lesions primarily rely on the morphologic interpretation of squamous epithelial cells (Pap cytology), in some setting accompanied by the detection of human papillomavirus DNA and have largely contributed to remarkable reduction of disease incidence in countries with implemented screening programs. However, these approaches are limited by a poor sensitivity and reproducibility of Pap cytology and low specificity for high grade cervical intraepithelial neoplasia of HPV DNA detection assays. Early detection might be improved by complementing or even replacing these tests by markers which are more directly related to molecular events triggering HPV-induced carcinogenesis and thereby might deliver more accurate diagnostic performance. The delineation of molecular changes which occur during different stages of HPV infections and the identification of changes which induce neoplastic alterations allow for the detection of markers that specifically highlight the transforming stage of the infection where viral oncogenes are overexpressed and therefore allow for a more specific diagnosis of lesions that require treatment. The evaluation of such markers in clinical studies revealed that some indeed show an improved diagnostic performance compared to Pap cytology or HPV DNA tests only.

  20. Relative efficacy of radiographic and radionuclide bone surveys in the detection of the skeletal lesions of histiocytosis X

    SciTech Connect

    Parker, B.R.; Pinckney, L.; Etcubanas, E.

    1980-02-01

    Radionuclide studies have been considered a more sensitive indicator of the presence of the bony lesions of histiocytosis X in children that have radiographic bone surveys. Our results suggest that the opposite is true. Although positive correlation between bone scans and radiographs was found in eight of nine patients, only 35% of the individual lesions visible on radiographs were seen on radionuclide studies. Results of radionuclide studies did not correlate with age or sex of the patient, presence or duration of symptoms, radiographic appearance, or anatomic location of lesions. Our results suggest that the radiographic skeletal survey is more sensitive than radionuclide studies in detecting the skeletal lesions of histiocytosis X.

  1. Autonomic dysfunction in multiple sclerosis.

    PubMed

    Racosta, Juan Manuel; Kimpinski, Kurt; Morrow, Sarah Anne; Kremenchutzky, Marcelo

    2015-12-01

    Autonomic dysfunction is a prevalent and significant cause of disability among patients with multiple sclerosis. Autonomic dysfunction in multiple sclerosis is usually explained by lesions within central nervous system regions responsible for autonomic regulation, but novel evidence suggests that other factors may be involved as well. Additionally, the interactions between the autonomic nervous system and the immune system have generated increased interest about the role of autonomic dysfunction in the pathogenesis of multiple sclerosis. In this paper we analyze systematically the most relevant signs and symptoms of autonomic dysfunction in MS, considering separately their potential causes and implications.

  2. Detection of circulating pancreas epithelial cells in patients with pancreatic cystic lesions.

    PubMed

    Rhim, Andrew D; Thege, Fredrik I; Santana, Steven M; Lannin, Timothy B; Saha, Trisha N; Tsai, Shannon; Maggs, Lara R; Kochman, Michael L; Ginsberg, Gregory G; Lieb, John G; Chandrasekhara, Vinay; Drebin, Jeffrey A; Ahmad, Nuzhat; Yang, Yu-Xiao; Kirby, Brian J; Stanger, Ben Z

    2014-03-01

    Hematogenous dissemination is thought to be a late event in cancer progression. We recently showed in a genetic model of pancreatic ductal adenocarcinoma that pancreas cells can be detected in the bloodstream before tumor formation. To confirm these findings in humans, we used microfluidic geometrically enhanced differential immunocapture to detect circulating pancreas epithelial cells in patient blood samples. We captured more than 3 circulating pancreas epithelial cells/mL in 7 of 21 (33%) patients with cystic lesions and no clinical diagnosis of cancer (Sendai criteria negative), 8 of 11 (73%) with pancreatic ductal adenocarcinoma, and in 0 of 19 patients without cysts or cancer (controls). These findings indicate that cancer cells are present in the circulation of patients before tumors are detected, which might be used in risk assessment. PMID:24333829

  3. Detection of circulating pancreas epithelial cells in patients with pancreatic cystic lesions.

    PubMed

    Rhim, Andrew D; Thege, Fredrik I; Santana, Steven M; Lannin, Timothy B; Saha, Trisha N; Tsai, Shannon; Maggs, Lara R; Kochman, Michael L; Ginsberg, Gregory G; Lieb, John G; Chandrasekhara, Vinay; Drebin, Jeffrey A; Ahmad, Nuzhat; Yang, Yu-Xiao; Kirby, Brian J; Stanger, Ben Z

    2014-03-01

    Hematogenous dissemination is thought to be a late event in cancer progression. We recently showed in a genetic model of pancreatic ductal adenocarcinoma that pancreas cells can be detected in the bloodstream before tumor formation. To confirm these findings in humans, we used microfluidic geometrically enhanced differential immunocapture to detect circulating pancreas epithelial cells in patient blood samples. We captured more than 3 circulating pancreas epithelial cells/mL in 7 of 21 (33%) patients with cystic lesions and no clinical diagnosis of cancer (Sendai criteria negative), 8 of 11 (73%) with pancreatic ductal adenocarcinoma, and in 0 of 19 patients without cysts or cancer (controls). These findings indicate that cancer cells are present in the circulation of patients before tumors are detected, which might be used in risk assessment.

  4. Functionalization of gadolinium metallofullerenes for detecting atherosclerotic plaque lesions by cardiovascular magnetic resonance

    PubMed Central

    2013-01-01

    Background The hallmark of atherosclerosis is the accumulation of plaque in vessel walls. This process is initiated when monocytic cells differentiate into macrophage foam cells under conditions with high levels of atherogenic lipoproteins. Vulnerable plaque can dislodge, enter the blood stream, and result in acute myocardial infarction and stroke. Imaging techniques such as cardiovascular magnetic resonance (CMR) provides one strategy to identify patients with plaque accumulation. Methods We synthesized an atherosclerotic-targeting contrast agent (ATCA) in which gadolinium (Gd)-containing endohedrals were functionalized and formulated into liposomes with CD36 ligands intercalated into the lipid bilayer. In vitro assays were used to assess the specificity of the ATCA for foam cells. The ability of ATCA to detect atherosclerotic plaque lesions in vivo was assessed using CMR. Results The ATCA was able to detect scavenger receptor (CD36)-expressing foam cells in vitro and were specifically internalized via the CD36 receptor as determined by focused ion beam/scanning electron microscopy (FIB-SEM) and Western blotting analysis of CD36 receptor-specific signaling pathways. The ATCA exhibited time-dependent accumulation in atherosclerotic plaque lesions of ApoE −/− mice as determined using CMR. No ATCA accumulation was observed in vessels of wild type (C57/b6) controls. Non-targeted control compounds, without the plaque-targeting moieties, were not taken up by foam cells in vitro and did not bind plaque in vivo. Importantly, the ATCA injection was well tolerated, did not demonstrate toxicity in vitro or in vivo, and no accumulation was observed in the major organs. Conclusions The ATCA is specifically internalized by CD36 receptors on atherosclerotic plaque providing enhanced visualization of lesions under physiological conditions. These ATCA may provide new tools for physicians to non-invasively detect atherosclerotic disease. PMID:23324435

  5. Computer-assisted lesion detection system for stomach screening using stomach shape and appearance models

    NASA Astrophysics Data System (ADS)

    Midoh, Y.; Nakamura, M.; Takashima, M.; Nakamae, K.; Fujioka, H.

    2007-03-01

    In Japan, stomach cancer is one of the three most common causes of death from cancer. Since periodic health checks of stomach X-rays have become more widely carried out, the physicians' burdens have been increasing in the mass screening to detect initial symptoms of a disease. For the purpose of automatic diagnosis, we try to develop a computer-assisted lesion detection system for stomach screening. The proposed system has two databases. One is the stomach shape database that consists of the computer graphics stomach 3D models based on biomechanics simulation and their projected 2D images. The other is the normal appearance database that is constructed by learning patterns in a normal patient training set. The stomach contour is extracted from an X-ray image including a barium filled region by the following steps. Firstly, the approximated stomach region is obtained by nonrigid registration based on mutual information. We define nonrigid transformation as one that includes translations, rotations, scaling, air-barium interface and weights of eigenvectors determined by principal components analysis in the stomach shape database. Secondly, the accurate stomach contour is extracted from the gradient of an image by using the Dynamic Programming. After then, stomach lesions are detected by inspecting whether the Mahalanobis distance from the mean in the normal appearance database is longer than a suitable value on the extracted stomach contour. We applied our system to 75 X-ray images of barium-filled stomach to show its validity.

  6. Radiographic detection of thoracic lesions in adult cows: A retrospective study of 42 cases (1995–2002)

    PubMed Central

    Masseau, Isabelle; Fecteau, Gilles; Breton, Luc; Hélie, Pierre; Beauregard, Guy; Blond, Laurent

    2008-01-01

    Medical records of 42 cows that underwent both thoracic radiographic and postmortem examinations within a period of 7 days were reviewed to develop an evaluation grid to interpret bovine thoracic radiographs and to determine the sensitivity and the specificity of thoracic radiographs for detection of thoracic lesions, based on postmortem examination. Most cows (64%) had clinical signs of respiratory disease, whereas 19% showed signs of cardiac problems. The sensitivity and specificity of radiographs for identifying cows with thoracic lesions were 94% and 50%, respectively. In this study, with a prevalence of thoracic lesions of 86%, the positive- and negative-predictive values were 92% and 57%, respectively. This study provides an evaluation grid that allows standardization of the reading of bovine thoracic radiographs and the identification of most thoracic lesions. Bovine thoracic radiographs are useful in detecting thoracic lesions in cows. PMID:18390098

  7. High throughput image cytometry for detection of suspicious lesions in the oral cavity

    NASA Astrophysics Data System (ADS)

    MacAulay, Calum; Poh, Catherine F.; Guillaud, Martial; Michele Williams, Pamela; Laronde, Denise M.; Zhang, Lewei; Rosin, Miriam P.

    2012-08-01

    The successful management of oral cancer depends upon early detection, which relies heavily on the clinician's ability to discriminate sometimes subtle alterations of the infrequent premalignant lesions from the more common reactive and inflammatory conditions in the oral mucosa. Even among experienced oral specialists this can be challenging, particularly when using new wide field-of-view direct fluorescence visualization devices clinically introduced for the recognition of at-risk tissue. The objective of this study is to examine if quantitative cytometric analysis of oral brushing samples could facilitate the assessment of the risk of visually ambiguous lesions. About 369 cytological samples were collected and analyzed: (1) 148 samples from pathology-proven sites of SCC, carcinoma in situ or severe dysplasia; (2) 77 samples from sites with inflammation, infection, or trauma, and (3) 144 samples from normal sites. These were randomly separated into training and test sets. The best algorithm correctly recognized 92.5% of the normal samples, 89.4% of the abnormal samples, 86.2% of the confounders in the training set as well as 100% of the normal samples, and 94.4% of the abnormal samples in the test set. These data suggest that quantitative cytology could reduce by more than 85% the number of visually suspect lesions requiring further assessment by biopsy.

  8. Light diffuse reflectance for detection and differentiation of teeth caries lesions

    NASA Astrophysics Data System (ADS)

    Borisova, E.; Uzunov, Tz.; Valkanov, S.; Avramov, L.

    2007-05-01

    One of the goals of the contemporary dentistry is differentiation between carious stages that must be fast, non-invasive procedure, which will allow to the dentists to make reliable judgments. One suitable candidate for such method is reflectance spectroscopy. The objectives of current study are to determine the feasibility of applying the light reflectance spectroscopy technique for detection of different carious stages; therefore reflectance spectra of teeth illuminated at 450- 900 nm light were recorded. There are obtained reflectance signals from the healthy enamel, dentine and different lesion stages of the investigated teeth. These spectra are compared to that, obtained by non-carious tooth lesions - fluorosa and odontolithiasis, resembling on initial carious stages. There is observed a significant decrease of the intensity of the reflected light in blue region in the case of caries. Reflectance signals, obtained from non-carious lesions also have significantly different character and could be used for differentiation between them and initial carious stages. An algorithm for differentiation between carious stages is proposed with diagnostic accuracy achieved up to 86,1% between precarious stage and sound tooth and 100% for determination of deep cavitation. Some comments about role of teeth enamel structure and anisotropy factor of dental layers on the results obtained are also made.

  9. Method to improve cancerous lesion detection sensitivity in a dedicated dual-head scintimammography system

    DOEpatents

    Kieper, Douglas Arthur; Majewski, Stanislaw; Welch, Benjamin L.

    2012-07-03

    An improved method for enhancing the contrast between background and lesion areas of a breast undergoing dual-head scintimammographic examination comprising: 1) acquiring a pair of digital images from a pair of small FOV or mini gamma cameras compressing the breast under examination from opposing sides; 2) inverting one of the pair of images to align or co-register with the other of the images to obtain co-registered pixel values; 3) normalizing the pair of images pixel-by-pixel by dividing pixel values from each of the two acquired images and the co-registered image by the average count per pixel in the entire breast area of the corresponding detector; and 4) multiplying the number of counts in each pixel by the value obtained in step 3 to produce a normalization enhanced two dimensional contrast map. This enhanced (increased contrast) contrast map enhances the visibility of minor local increases (uptakes) of activity over the background and therefore improves lesion detection sensitivity, especially of small lesions.

  10. Method to improve cancerous lesion detection sensitivity in a dedicated dual-head scintimammography system

    DOEpatents

    Kieper, Douglas Arthur; Majewski, Stanislaw; Welch, Benjamin L.

    2008-10-28

    An improved method for enhancing the contrast between background and lesion areas of a breast undergoing dual-head scintimammographic examination comprising: 1) acquiring a pair of digital images from a pair of small FOV or mini gamma cameras compressing the breast under examination from opposing sides; 2) inverting one of the pair of images to align or co-register with the other of the images to obtain co-registered pixel values; 3) normalizing the pair of images pixel-by-pixel by dividing pixel values from each of the two acquired images and the co-registered image by the average count per pixel in the entire breast area of the corresponding detector; and 4) multiplying the number of counts in each pixel by the value obtained in step 3 to produce a normalization enhanced two dimensional contrast map. This enhanced (increased contrast) contrast map enhances the visibility of minor local increases (uptakes) of activity over the background and therefore improves lesion detection sensitivity, especially of small lesions.

  11. Retinal image analysis to detect and quantify lesions associated with diabetic retinopathy.

    PubMed

    Sánchez, C I; Hornero, R; López, M I; Poza, J

    2004-01-01

    An automatic method to detect hard exudates, a lesion associated with diabetic retinopathy, is proposed. The algorithm found on their color, using a statistical classification, and their sharp edges, applying an edge detector, to localize them. A sensitivity of 79.62% with a mean number of 3 false positives per image is obtained in a database of 20 retinal image with variable color, brightness and quality. In that way, we evaluate the robustness of the method in order to make adequate to a clinical environment. Further efforts will be done to improve its performance.

  12. Retinal image analysis to detect and quantify lesions associated with diabetic retinopathy.

    PubMed

    Sánchez, C I; Hornero, R; López, M I; Poza, J

    2004-01-01

    An automatic method to detect hard exudates, a lesion associated with diabetic retinopathy, is proposed. The algorithm found on their color, using a statistical classification, and their sharp edges, applying an edge detector, to localize them. A sensitivity of 79.62% with a mean number of 3 false positives per image is obtained in a database of 20 retinal image with variable color, brightness and quality. In that way, we evaluate the robustness of the method in order to make adequate to a clinical environment. Further efforts will be done to improve its performance. PMID:17272012

  13. Automatic detection and segmentation of liver metastatic lesions on serial CT examinations

    NASA Astrophysics Data System (ADS)

    Ben Cohen, Avi; Diamant, Idit; Klang, Eyal; Amitai, Michal; Greenspan, Hayit

    2014-03-01

    In this paper we present a fully automated method for detection and segmentation of liver metastases on serial CT examinations (portal phase) given a 2D baseline segmentation mask. Our database contains 27 CT scans, baselines and follow-ups, of 12 patients and includes 22 test cases. Our method is based on the information given in the baseline CT scan which contains the lesion's segmentation mask marked manually by a radiologist. We use the 2D baseline segmentation mask to identify the lesion location in the follow-up CT scan using non-rigid image registration. The baseline CT scan is also used to locate regions of tissues surrounding the lesion and to map them onto the follow-up CT scan, in order to reduce the search area on the follow-up CT scan. Adaptive region-growing and mean-shift segmentation are used to obtain the final lesion segmentation. The segmentation results are compared to those obtained by a human radiologist. Compared to the reference standard our method made a correct RECIST 1.1 assessment for 21 out of 22 test cases. The average Dice index was 0.83 +/- 0.07, average Hausdorff distance was 7.85+/- 4.84 mm, average sensitivity was 0.87 +/- 0.11 and positive predictive value was 0.81 +/- 0.10. The segmentation performance and the RECIST assessment results look promising. We are pursuing the methodology further with expansion to 3D segmentation while increasing the dataset we are collecting from the CT abdomen unit at Sheba medical center.

  14. Multiple sclerosis.

    PubMed

    Filippi, Massimo; Preziosa, Paolo; Rocca, Maria A

    2016-01-01

    Due to its sensitivity to the different multiple sclerosis (MS)-related abnormalities, magnetic resonance imaging (MRI) has become an established tool to diagnose MS and to monitor its evolution. MRI has been included in the diagnostic workup of patients with clinically isolated syndromes suggestive of MS, and ad hoc criteria have been proposed and are regularly updated. In patients with definite MS, the ability of conventional MRI techniques to explain patients' clinical status and progression of disability is still suboptimal. Several advanced MRI-based technologies have been applied to estimate overall MS burden in the different phases of the disease. Their use has allowed the heterogeneity of MS pathology in focal lesions, normal-appearing white matter and gray matter to be graded in vivo. Recently, additional features of MS pathology, including macrophage infiltration and abnormal iron deposition, have become quantifiable. All of this, combined with functional imaging techniques, is improving our understanding of the mechanisms associated with MS evolution. In the near future, the use of ultrahigh-field systems is likely to provide additional insight into disease pathophysiology. However, the utility of advanced MRI techniques in clinical trial monitoring and in assessing individual patients' response to treatment still needs to be assessed. PMID:27432676

  15. Positron emission mammography (PEM): Effect of activity concentration, object size, and object contrast on phantom lesion detection

    SciTech Connect

    MacDonald, Lawrence R.; Wang, Carolyn L.; Eissa, Marna; Haseley, David; Kelly, Mary M.; Liu, Franklin; Parikh, Jay R.; Beatty, J. David; Rogers, James V.

    2012-10-15

    Purpose: To characterize the relationship between lesion detection sensitivity and injected activity as a function of lesion size and contrast on the PEM (positron emission mammography) Flex Solo II scanner using phantom experiments. Methods: Phantom lesions (spheres 4, 8, 12, 16, and 20 mm diameter) were randomly located in uniform background. Sphere activity concentrations were 3 to 21 times the background activity concentration (BGc). BGc was a surrogate for injected activity; BGc ranged from 0.44-4.1 kBq/mL, corresponding to 46-400 MBq injections. Seven radiologists read 108 images containing zero, one, or two spheres. Readers used a 5-point confidence scale to score the presence of spheres. Results: Sensitivity was 100% for lesions {>=}12 mm under all conditions except for one 12 mm sphere with the lowest contrast and lowest BGc (60% sensitivity). Sensitivity was 100% for 8 mm spheres when either contrast or BGc was high, and 100% for 4 mm spheres only when both contrast and BGc were highest. Sphere contrast recovery coefficients (CRC) were 49%, 34%, 26%, 14%, and 2.8% for the largest to smallest spheres. Cumulative specificity was 98%. Conclusions: Phantom lesion detection sensitivity depends more on sphere size and contrast than on BGc. Detection sensitivity remained {>=}90% for injected activities as low as 100 MBq, for lesions {>=}8 mm. Low CRC in 4 mm objects results in moderate detection sensitivity even for 400 MBq injected activity, making it impractical to optimize injected activity for such lesions. Low CRC indicates that when lesions <8 mm are observed on PEM images they are highly tracer avid with greater potential of clinical significance. High specificity (98%) suggests that image statistical noise does not lead to false positive findings. These results apply to the 85 mm thick object used to obtain them; lesion detectability should be better (worse) for thinner (thicker) objects based on the reduced (increased) influence of photon attenuation.

  16. The mystery of the origin of multiple sclerosis.

    PubMed Central

    McDonald, W I

    1986-01-01

    Our present understanding of the aetiology and pathogenesis of multiple sclerosis is discussed in relation to the views of Sir William Gowers. He perceived that both environmental and genetic factors might be implicated in the aetiology of the disease. Evidence for the former was first reported in 1903, but has become convincing only in the past 20 years; the nature of the environmental factor remains obscure. Evidence for a genetic influence on susceptibility has accumulated since the 1930s, the most compelling coming from the recent Canadian twin study. The number and mode of operation of the genetic factors is still uncertain, but there is evidence for the implication of genetically controlled cellular immune mechanisms in the pathogenesis of the disease. The precise relationship between transient changes in immunological status and the development of new lesions has yet to be defined; magnetic resonance imaging (MRI) promises to play a significant role in this analysis because of its sensitivity in detecting abnormalities in multiple sclerosis. MRI is not in itself specific; it is probable that the similar appearances in multiple sclerosis and cerebral vascular disease both derive at least in part from the influence of astrocytic gliosis on proton content and distribution. The significance of the gliosis is uncertain. Gowers believed that the primary defect in multiple sclerosis lay in the astrocyte. Recent observations on the immunological functions of this cell in vitro suggest that it could be involved early in the pathogenesis of the lesion. Images PMID:2936869

  17. Pancreatic necrosis in progressive systemic sclerosis.

    PubMed Central

    Abraham, A A; Joos, A

    1980-01-01

    Fatal pancreatic necrosis, secondary to extensive acute arteritic changes, is reported in a case of progressive systemic sclerosis. The patient presented first with hypertension and renal involvement, with active vascular lesions demonstrated by biopsy. The renal lesion at necropsy was inactive, showing the characteristic concentric fibrosis only, while the pancreatic vascular lesions were both chronic proliferative and acute in type. Images PMID:7436566

  18. Detection of retinal blood vessel changes in multiple sclerosis with optical coherence tomography.

    PubMed

    Bhaduri, Basanta; Nolan, Ryan M; Shelton, Ryan L; Pilutti, Lara A; Motl, Robert W; Moss, Heather E; Pula, John H; Boppart, Stephen A

    2016-06-01

    Although retinal vasculitis is common in multiple sclerosis (MS), it is not known if MS is associated with quantitative abnormalities in retinal blood vessels (BVs). Optical coherence tomography (OCT) is suitable for examining the integrity of the anterior visual pathways in MS. In this paper we have compared the size and number of retinal blood vessels in patients with MS, with and without a history of optic neuritis (ON), and control subjects from the cross-sectional retinal images from OCT. Blood vessel diameter (BVD), blood vessel number (BVN), and retinal nerve fiber layer thickness (RNFLT) were extracted from OCT images collected from around the optic nerves of 129 eyes (24 control, 24 MS + ON, 81 MS-ON) of 71 subjects. Associations between blood vessel metrics, MS diagnosis, MS disability, ON, and RNFLT were evaluated using generalized estimating equation (GEE) models. MS eyes had a lower total BVD and BVN than control eyes. The effect was more pronounced with increased MS disability, and persisted in multivariate models adjusting for RNFLT and ON history. Twenty-nine percent (29%) of MS subjects had fewer retinal blood vessels than all control subjects. MS diagnosis, disability, and ON history were not associated with average blood vessel size. The relationship between MS and lower total BVD/BVN is not accounted for by RNFLT or ON. Further study is needed to determine the relationship between OCT blood vessel metrics and qualitative retinal blood vessel abnormalities in MS. PMID:27375947

  19. Detection of retinal blood vessel changes in multiple sclerosis with optical coherence tomography.

    PubMed

    Bhaduri, Basanta; Nolan, Ryan M; Shelton, Ryan L; Pilutti, Lara A; Motl, Robert W; Moss, Heather E; Pula, John H; Boppart, Stephen A

    2016-06-01

    Although retinal vasculitis is common in multiple sclerosis (MS), it is not known if MS is associated with quantitative abnormalities in retinal blood vessels (BVs). Optical coherence tomography (OCT) is suitable for examining the integrity of the anterior visual pathways in MS. In this paper we have compared the size and number of retinal blood vessels in patients with MS, with and without a history of optic neuritis (ON), and control subjects from the cross-sectional retinal images from OCT. Blood vessel diameter (BVD), blood vessel number (BVN), and retinal nerve fiber layer thickness (RNFLT) were extracted from OCT images collected from around the optic nerves of 129 eyes (24 control, 24 MS + ON, 81 MS-ON) of 71 subjects. Associations between blood vessel metrics, MS diagnosis, MS disability, ON, and RNFLT were evaluated using generalized estimating equation (GEE) models. MS eyes had a lower total BVD and BVN than control eyes. The effect was more pronounced with increased MS disability, and persisted in multivariate models adjusting for RNFLT and ON history. Twenty-nine percent (29%) of MS subjects had fewer retinal blood vessels than all control subjects. MS diagnosis, disability, and ON history were not associated with average blood vessel size. The relationship between MS and lower total BVD/BVN is not accounted for by RNFLT or ON. Further study is needed to determine the relationship between OCT blood vessel metrics and qualitative retinal blood vessel abnormalities in MS.

  20. Detection of retinal blood vessel changes in multiple sclerosis with optical coherence tomography

    PubMed Central

    Bhaduri, Basanta; Nolan, Ryan M.; Shelton, Ryan L.; Pilutti, Lara A.; Motl, Robert W.; Moss, Heather E.; Pula, John H.; Boppart, Stephen A.

    2016-01-01

    Although retinal vasculitis is common in multiple sclerosis (MS), it is not known if MS is associated with quantitative abnormalities in retinal blood vessels (BVs). Optical coherence tomography (OCT) is suitable for examining the integrity of the anterior visual pathways in MS. In this paper we have compared the size and number of retinal blood vessels in patients with MS, with and without a history of optic neuritis (ON), and control subjects from the cross-sectional retinal images from OCT. Blood vessel diameter (BVD), blood vessel number (BVN), and retinal nerve fiber layer thickness (RNFLT) were extracted from OCT images collected from around the optic nerves of 129 eyes (24 control, 24 MS + ON, 81 MS-ON) of 71 subjects. Associations between blood vessel metrics, MS diagnosis, MS disability, ON, and RNFLT were evaluated using generalized estimating equation (GEE) models. MS eyes had a lower total BVD and BVN than control eyes. The effect was more pronounced with increased MS disability, and persisted in multivariate models adjusting for RNFLT and ON history. Twenty-nine percent (29%) of MS subjects had fewer retinal blood vessels than all control subjects. MS diagnosis, disability, and ON history were not associated with average blood vessel size. The relationship between MS and lower total BVD/BVN is not accounted for by RNFLT or ON. Further study is needed to determine the relationship between OCT blood vessel metrics and qualitative retinal blood vessel abnormalities in MS. PMID:27375947

  1. Diffusion tensor imaging based network analysis detects alterations of neuroconnectivity in patients with clinically early relapsing-remitting multiple sclerosis.

    PubMed

    Li, Yang; Jewells, Valerie; Kim, Minjeong; Chen, Yasheng; Moon, Andrew; Armao, Diane; Troiani, Luigi; Markovic-Plese, Silva; Lin, Weili; Shen, Dinggang

    2013-12-01

    Although it is inarguable that conventional MRI (cMRI) has greatly contributed to the diagnosis and assessment of multiple sclerosis (MS), cMRI does not show close correlation with clinical findings or pathologic features, and is unable to predict prognosis or stratify disease severity. To this end, diffusion tensor imaging (DTI) with tractography and neuroconnectivity analysis may assist disease assessment in MS. We, therefore, attempted this pilot study for initial assessment of early relapsing-remitting MS (RRMS). Neuroconnectivity analysis was used for evaluation of 24 early RRMS patients within 2 years of presentation, and compared to the network measures of a group of 30 age-and-gender-matched normal control subjects. To account for the situation that the connections between two adjacent regions may be disrupted by an MS lesion, a new metric, network communicability, was adopted to measure both direct and indirect connections. For each anatomical area, the brain network communicability and average path length were computed and compared to characterize the network changes in efficiencies. Statistically significant (P < 0.05) loss of communicability was revealed in our RRMS cohort, particularly in the frontal and hippocampal/parahippocampal regions as well as the motor strip and occipital lobes. Correlation with the 25-foot Walk test with communicability measures in the left superior frontal (r = -0.71) as well as the left superior temporal gyrus (r = -0.43) and left postcentral gyrus (r = -0.41) were identified. Additionally identified were increased communicability between the deep gray matter structures (left thalamus and putamen) with the major interhemispheric and intrahemispheric white matter tracts, the corpus callosum, and cingulum, respectively. These foci of increased communicability are thought to represent compensatory changes. The proposed DTI-based neuroconnectivity analysis demonstrated quantifiable, structurally relevant alterations of fiber

  2. Diffusion tensor imaging based network analysis detects alterations of neuroconnectivity in patients with clinically early relapsing-remitting multiple sclerosis.

    PubMed

    Li, Yang; Jewells, Valerie; Kim, Minjeong; Chen, Yasheng; Moon, Andrew; Armao, Diane; Troiani, Luigi; Markovic-Plese, Silva; Lin, Weili; Shen, Dinggang

    2013-12-01

    Although it is inarguable that conventional MRI (cMRI) has greatly contributed to the diagnosis and assessment of multiple sclerosis (MS), cMRI does not show close correlation with clinical findings or pathologic features, and is unable to predict prognosis or stratify disease severity. To this end, diffusion tensor imaging (DTI) with tractography and neuroconnectivity analysis may assist disease assessment in MS. We, therefore, attempted this pilot study for initial assessment of early relapsing-remitting MS (RRMS). Neuroconnectivity analysis was used for evaluation of 24 early RRMS patients within 2 years of presentation, and compared to the network measures of a group of 30 age-and-gender-matched normal control subjects. To account for the situation that the connections between two adjacent regions may be disrupted by an MS lesion, a new metric, network communicability, was adopted to measure both direct and indirect connections. For each anatomical area, the brain network communicability and average path length were computed and compared to characterize the network changes in efficiencies. Statistically significant (P < 0.05) loss of communicability was revealed in our RRMS cohort, particularly in the frontal and hippocampal/parahippocampal regions as well as the motor strip and occipital lobes. Correlation with the 25-foot Walk test with communicability measures in the left superior frontal (r = -0.71) as well as the left superior temporal gyrus (r = -0.43) and left postcentral gyrus (r = -0.41) were identified. Additionally identified were increased communicability between the deep gray matter structures (left thalamus and putamen) with the major interhemispheric and intrahemispheric white matter tracts, the corpus callosum, and cingulum, respectively. These foci of increased communicability are thought to represent compensatory changes. The proposed DTI-based neuroconnectivity analysis demonstrated quantifiable, structurally relevant alterations of fiber

  3. Theoretical Analysis of Penalized Maximum-Likelihood Patlak Parametric Image Reconstruction in Dynamic PET for Lesion Detection.

    PubMed

    Yang, Li; Wang, Guobao; Qi, Jinyi

    2016-04-01

    Detecting cancerous lesions is a major clinical application of emission tomography. In a previous work, we studied penalized maximum-likelihood (PML) image reconstruction for lesion detection in static PET. Here we extend our theoretical analysis of static PET reconstruction to dynamic PET. We study both the conventional indirect reconstruction and direct reconstruction for Patlak parametric image estimation. In indirect reconstruction, Patlak parametric images are generated by first reconstructing a sequence of dynamic PET images, and then performing Patlak analysis on the time activity curves (TACs) pixel-by-pixel. In direct reconstruction, Patlak parametric images are estimated directly from raw sinogram data by incorporating the Patlak model into the image reconstruction procedure. PML reconstruction is used in both the indirect and direct reconstruction methods. We use a channelized Hotelling observer (CHO) to assess lesion detectability in Patlak parametric images. Simplified expressions for evaluating the lesion detectability have been derived and applied to the selection of the regularization parameter value to maximize detection performance. The proposed method is validated using computer-based Monte Carlo simulations. Good agreements between the theoretical predictions and the Monte Carlo results are observed. Both theoretical predictions and Monte Carlo simulation results show the benefit of the indirect and direct methods under optimized regularization parameters in dynamic PET reconstruction for lesion detection, when compared with the conventional static PET reconstruction.

  4. Cardiac motion compensation and resolution modeling in simultaneous PET-MR: a cardiac lesion detection study.

    PubMed

    Petibon, Y; Ouyang, J; Zhu, X; Huang, C; Reese, T G; Chun, S Y; Li, Q; El Fakhri, G

    2013-04-01

    Cardiac motion and partial volume effects (PVE) are two of the main causes of image degradation in cardiac PET. Motion generates artifacts and blurring while PVE lead to erroneous myocardial activity measurements. Newly available simultaneous PET-MR scanners offer new possibilities in cardiac imaging as MRI can assess wall contractility while collecting PET perfusion data. In this perspective, we develop a list-mode iterative reconstruction framework incorporating both tagged-MR derived non-rigid myocardial wall motion and position dependent detector point spread function (PSF) directly into the PET system matrix. In this manner, our algorithm performs both motion 'deblurring' and PSF deconvolution while reconstructing images with all available PET counts. The proposed methods are evaluated in a beating non-rigid cardiac phantom whose hot myocardial compartment contains small transmural and non-transmural cold defects. In order to accelerate imaging time, we investigate collecting full and half k-space tagged MR data to obtain tagged volumes that are registered using non-rigid B-spline registration to yield wall motion information. Our experimental results show that tagged-MR based motion correction yielded an improvement in defect/myocardium contrast recovery of 34-206% as compared to motion uncorrected studies. Likewise, lesion detectability improved by respectively 115-136% and 62-235% with MR-based motion compensation as compared to gating and no motion correction and made it possible to distinguish non-transmural from transmural defects, which has clinical significance given the inherent limitations of current single modality imaging in identifying the amount of residual ischemia. The incorporation of PSF modeling within the framework of MR-based motion compensation significantly improved defect/myocardium contrast recovery (5.1-8.5%, p < 0.01) and defect detectability (39-56%, p < 0.01). No statistical difference was found in PET contrast and lesion

  5. Cardiac motion compensation and resolution modeling in simultaneous PET-MR: a cardiac lesion detection study

    NASA Astrophysics Data System (ADS)

    Petibon, Y.; Ouyang, J.; Zhu, X.; Huang, C.; Reese, T. G.; Chun, S. Y.; Li, Q.; El Fakhri, G.

    2013-04-01

    Cardiac motion and partial volume effects (PVE) are two of the main causes of image degradation in cardiac PET. Motion generates artifacts and blurring while PVE lead to erroneous myocardial activity measurements. Newly available simultaneous PET-MR scanners offer new possibilities in cardiac imaging as MRI can assess wall contractility while collecting PET perfusion data. In this perspective, we develop a list-mode iterative reconstruction framework incorporating both tagged-MR derived non-rigid myocardial wall motion and position dependent detector point spread function (PSF) directly into the PET system matrix. In this manner, our algorithm performs both motion ‘deblurring’ and PSF deconvolution while reconstructing images with all available PET counts. The proposed methods are evaluated in a beating non-rigid cardiac phantom whose hot myocardial compartment contains small transmural and non-transmural cold defects. In order to accelerate imaging time, we investigate collecting full and half k-space tagged MR data to obtain tagged volumes that are registered using non-rigid B-spline registration to yield wall motion information. Our experimental results show that tagged-MR based motion correction yielded an improvement in defect/myocardium contrast recovery of 34-206% as compared to motion uncorrected studies. Likewise, lesion detectability improved by respectively 115-136% and 62-235% with MR-based motion compensation as compared to gating and no motion correction and made it possible to distinguish non-transmural from transmural defects, which has clinical significance given the inherent limitations of current single modality imaging in identifying the amount of residual ischemia. The incorporation of PSF modeling within the framework of MR-based motion compensation significantly improved defect/myocardium contrast recovery (5.1-8.5%, p < 0.01) and defect detectability (39-56%, p < 0.01). No statistical difference was found in PET contrast and lesion

  6. Diagnostic power of diffuse reflectance spectroscopy for targeted detection of breast lesions with microcalcifications

    PubMed Central

    Soares, Jaqueline S.; Barman, Ishan; Dingari, Narahara Chari; Volynskaya, Zoya; Liu, Wendy; Klein, Nina; Plecha, Donna; Dasari, Ramachandra R.; Fitzmaurice, Maryann

    2013-01-01

    Microcalcifications geographically target the location of abnormalities within the breast and are of critical importance in breast cancer diagnosis. However, despite stereotactic guidance, core needle biopsy fails to retrieve microcalcifications in up to 15% of patients. Here, we introduce an approach based on diffuse reflectance spectroscopy for detection of microcalcifications that focuses on variations in optical absorption stemming from the calcified clusters and the associated cross-linking molecules. In this study, diffuse reflectance spectra are acquired ex vivo from 203 sites in fresh biopsy tissue cores from 23 patients undergoing stereotactic breast needle biopsies. By correlating the spectra with the corresponding radiographic and histologic assessment, we have developed a support vector machine-derived decision algorithm, which shows high diagnostic power (positive predictive value and negative predictive value of 97% and 88%, respectively) for diagnosis of lesions with microcalcifications. We further show that these results are robust and not due to any spurious correlations. We attribute our findings to the presence of proteins (such as elastin), and desmosine and isodesmosine cross-linkers in the microcalcifications. It is important to note that the performance of the diffuse reflectance decision algorithm is comparable to one derived from the corresponding Raman spectra, and the considerably higher intensity of the reflectance signal enables the detection of the targeted lesions in a fraction of the spectral acquisition time. Our findings create a unique landscape for spectroscopic validation of breast core needle biopsy for detection of microcalcifications that can substantially improve the likelihood of an adequate, diagnostic biopsy in the first attempt. PMID:23267090

  7. Computed Tomography-Derived Fractional Flow Reserve in the Detection of Lesion-Specific Ischemia

    PubMed Central

    Xu, Rende; Li, Chenguang; Qian, Juying; Ge, Junbo

    2015-01-01

    Abstract Invasive fractional flow reserve (FFR) is the gold standard for the determination of physiologic stenosis severity and the need for revascularization. FFR computed from standard acquired coronary computed tomographic angiography datasets (FFRCT) is an emerging technology which allows calculation of FFR using resting image data from coronary computed tomographic angiography (CCTA). However, the diagnostic accuracy of FFRCT in the evaluation of lesion-specific myocardial ischemia remains to be confirmed, especially in patients with intermediate coronary stenosis. We performed an integrated analysis of data from 3 prospective, international, and multicenter trials, which assessed the diagnostic performance of FFRCT using invasive FFR as a reference standard. Three studies evaluating 609 patients and 1050 vessels were included. The total calculated sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of FFRCT were 82.8%, 77.7%, 60.8%, 91.6%, and 79.2%, respectively, for the per-vessel analysis, and 89.4%, 70.5%, 69.7%, 89.7%, and 78.7%, respectively, for the per-patient analysis. Compared with CCTA alone, FFRCT demonstrated significantly improved accuracy (P < 0.001) in detecting lesion-specific ischemia. In patients with intermediate coronary stenosis, FFRCT remained both highly sensitive and specific with respect to the diagnosis of ischemia. In conclusion, FFRCT appears to be a reliable noninvasive alternative to invasive FFR, as it demonstrates high accuracy in the determination of anatomy and lesion-specific ischemia, which justifies the performance of additional randomized controlled trials to evaluate both the clinical benefits and the cost-effectiveness of FFRCT-guided coronary revascularization. PMID:26579804

  8. Comparison of 64-Detector CT Colonography and Conventional Colonoscopy in the Detection of Colorectal Lesions

    PubMed Central

    Devir, Cigdem; Kebapci, Mahmut; Temel, Tuncer; Ozakyol, Aysegul

    2016-01-01

    Background: Colon cancer is a leading cause of morbidity and mortality in developed countries. The early detection of colorectal cancer using screening programs is important for managing early-stage colorectal cancers and polyps. Modalities that allow examination of the entire colon are conventional colonoscopy, double contrast barium enema examination and multi-detector computed tomography (MDCT) colonography. Objectives: To compare CT colonography and conventional colonoscopy results and to evaluate the accuracy of CT colonography for detecting colorectal lesions. Patients and Methods: In a prospective study performed at Gastroenterology and Radiology Departments of Medical Faculty of Eskisehir Osmangazi University, CT colonography and colonoscopy results of 31 patients with family history of colorectal carcinoma, personal or family history of colorectal polyps, lower gastrointestinal tract bleeding, change in bowel habits, iron deficiency anemia and abdominal pain were compared. Regardless of the size, CT colonography and conventional colonoscopy findings for all the lesions were cross - tabulated and the sensitivity, specificity, and positive and negative predictive values were calculated. To assess the agreement between CT colonography and conventional colonoscopy examinations, the Kappa coefficient of agreementt was used. Statistical analysis was performed by SPSS ver 15.0. Results: Regardless of the size, MDCT colonography showed 83% sensitivity and 95% specificity, with a positive predictive value of 95% and a negative predictive value of 83% for the detection of colorectal polyps and masses. MDCT colonography displayed 92% sensitivity and 95% specificity, with a positive predictive value of 92% and a negative predictive value of 95% for polyps ≥ 10 mm. For polyps between 6mm and 9 mm, MDCT colonography displayed 75% sensitivity and 100% specificity, with a positive predictive value of 100% and a negative predictive value of 90%. For polyps ≤ 5 mm MDCT

  9. Diffusion-Weighted Imaging with Two Different b-Values in Detection of Solid Focal Liver Lesions

    PubMed Central

    Yang, Da-wei; Wang, Ke-yang; Yao, Xun; Ye, Hui-yi; Jiang, Tao; Liu, Yuan; Gao, Jia-yin; Chen, Min; Zhou, Cheng; Yang, Zheng-han

    2016-01-01

    One hundred and eighty-two consecutive patients with suspected liver disease were recruited to receive diffusion-weighted imaging (DWI) with two different b-values, in comparison with T2-weighted imaging (T2WI). The detection rate of three MR sequences in solid focal liver lesions (FLLs) and subgroup analyses were performed. Our prospective study found that DWI600 was equivalent to DWI100 and T2WI for the detection of solid FLLs overall but was significantly more accurate in the detection of malignant solid FLLs and lesions larger than 10 mm. PMID:27019851

  10. Molecular assays for detecting Aphanomyces invadans in ulcerative mycotic fish lesions.

    PubMed

    Vandersea, Mark W; Litaker, R Wayne; Yonnish, Bryan; Sosa, Emilio; Landsberg, Jan H; Pullinger, Chris; Moon-Butzin, Paula; Green, Jason; Morris, James A; Kator, Howard; Noga, Edward J; Tester, Patricia A

    2006-02-01

    The pathogenic oomycete Aphanomyces invadans is the primary etiological agent in ulcerative mycosis, an ulcerative skin disease caused by a fungus-like agent of wild and cultured fish. We developed sensitive PCR and fluorescent peptide nucleic acid in situ hybridization (FISH) assays to detect A. invadans. Laboratory-challenged killifish (Fundulus heteroclitus) were first tested to optimize and validate the assays. Skin ulcers of Atlantic menhaden (Brevoortia tyrannus) from populations found in the Pamlico and Neuse River estuaries in North Carolina were then surveyed. Results from both assays indicated that all of the lesioned menhaden (n = 50) collected in September 2004 were positive for A. invadans. Neither the FISH assay nor the PCR assay cross-reacted with other closely related oomycetes. These results provided strong evidence that A. invadans is the primary oomycete pathogen in ulcerative mycosis and demonstrated the utility of the assays. The FISH assay is the first molecular assay to provide unambiguous visual confirmation that hyphae in the ulcerated lesions were exclusively A. invadans. PMID:16461710

  11. Statistical image segmentation for the detection of skin lesion borders in UV fluorescence excitation

    NASA Astrophysics Data System (ADS)

    Ortega-Martinez, Antonio; Padilla-Martinez, Juan Pablo; Franco, Walfre

    2016-04-01

    The skin contains several fluorescent molecules or fluorophores that serve as markers of structure, function and composition. UV fluorescence excitation photography is a simple and effective way to image specific intrinsic fluorophores, such as the one ascribed to tryptophan which emits at a wavelength of 345 nm upon excitation at 295 nm, and is a marker of cellular proliferation. Earlier, we built a clinical UV photography system to image cellular proliferation. In some samples, the naturally low intensity of the fluorescence can make it difficult to separate the fluorescence of cells in higher proliferation states from background fluorescence and other imaging artifacts -- like electronic noise. In this work, we describe a statistical image segmentation method to separate the fluorescence of interest. Statistical image segmentation is based on image averaging, background subtraction and pixel statistics. This method allows to better quantify the intensity and surface distributions of fluorescence, which in turn simplify the detection of borders. Using this method we delineated the borders of highly-proliferative skin conditions and diseases, in particular, allergic contact dermatitis, psoriatic lesions and basal cell carcinoma. Segmented images clearly define lesion borders. UV fluorescence excitation photography along with statistical image segmentation may serve as a quick and simple diagnostic tool for clinicians.

  12. Molecular Assays for Detecting Aphanomyces invadans in Ulcerative Mycotic Fish Lesions

    PubMed Central

    Vandersea, Mark W.; Litaker, R. Wayne; Yonnish, Bryan; Sosa, Emilio; Landsberg, Jan H.; Pullinger, Chris; Moon-Butzin, Paula; Green, Jason; Morris, James A.; Kator, Howard; Noga, Edward J.; Tester, Patricia A.

    2006-01-01

    The pathogenic oomycete Aphanomyces invadans is the primary etiological agent in ulcerative mycosis, an ulcerative skin disease caused by a fungus-like agent of wild and cultured fish. We developed sensitive PCR and fluorescent peptide nucleic acid in situ hybridization (FISH) assays to detect A. invadans. Laboratory-challenged killifish (Fundulus heteroclitus) were first tested to optimize and validate the assays. Skin ulcers of Atlantic menhaden (Brevoortia tyrannus) from populations found in the Pamlico and Neuse River estuaries in North Carolina were then surveyed. Results from both assays indicated that all of the lesioned menhaden (n = 50) collected in September 2004 were positive for A. invadans. Neither the FISH assay nor the PCR assay cross-reacted with other closely related oomycetes. These results provided strong evidence that A. invadans is the primary oomycete pathogen in ulcerative mycosis and demonstrated the utility of the assays. The FISH assay is the first molecular assay to provide unambiguous visual confirmation that hyphae in the ulcerated lesions were exclusively A. invadans. PMID:16461710

  13. CXCR-4 Targeted, Short Wave Infrared (SWIR) Emitting Nanoprobes for Enhanced Deep Tissue Imaging and Micrometastatic Lesion Detection

    PubMed Central

    Zevon, Margot; Ganapathy, Vidya; Kantamneni, Harini; Mingozzi, Marco; Kim, Paul; Adler, Derek; Sheng, Yang; Tan, Mei Chee; Pierce, Mark; Riman, Richard E.; Roth, Charles M.; Moghe, Prabhas V.

    2016-01-01

    Realizing the promise of precision medicine in cancer therapy depends on identifying and tracking of cancerous growths in order to maximize treatment options and improve patient outcomes. However, this goal of early detection remains unfulfilled by current clinical imaging techniques that fail to detect diseased lesions, due to their small size and sub-organ localization. With proper probes, optical imaging techniques can overcome this limitation by identifying the molecular phenotype of tumors at both macroscopic and microscopic scales. In this study, we propose the first use of nanophotonic short wave infrared technology to molecularly phenotype small sub-surface lesions for more sensitive detection and improved patient outcomes. To this end, we designed human serum albumin encapsulated rare-earth (RE) nanoparticles (ReANCs)[1, 2] with ligands for targeted lesion imaging. AMD3100, an antagonist to CXCR4 (a chemokine receptor involved in cell motility and a classic marker of cancer metastasis) was adsorbed onto ReANCs to form functionalized ReANCs (fReANCs). Functionalized nanoparticles were able to discriminate and preferentially accumulate in receptor positive lesions when injected intraperitoneally in a subcutaneous tumor model. Additionally, fReANCs, administered intravenously, were able to target sub-tissue tumor micro-lesions, at a maximum depth of 10.5 mm, in a lung metastatic model of breast cancer. Internal lesions identified with fReANCs were 2.25 times smaller than those detected with unfunctionalized ReANCs (p < .01) with the smallest tumor being 18.9 mm3. Thus, we present an integrated nanoprobe detection platform that allows target-specific identification of sub-tissue cancerous lesions. PMID:26514367

  14. Pigment pattern and depth-of-invasion analysis of skin lesions for malignant melanoma detection

    NASA Astrophysics Data System (ADS)

    Dhawan, Atam P.; Kini, Prashanth

    1990-07-01

    A clinical instrument called a "Nevoscope" is used to image skin-lesions. The lesion is transilluminated by a fiber-optic annular ring light source that directs light into the skin area surrounding the lesion and thus forming a virtual source just beneath the lesion. Mirrors uniformly spaced around the lesion and tilted at various angles, provide orthographic projections of the skin lesion. Additional views are obtained by rotating the mirror assembly. These multiple views are used in a direct 3-D reconstruction of the lesion to estimate its depth of penetration. A pigment pattern analysis is performed on the direct view. This includes both color and texture segmentation. In this paper, we present preliminary results of our 3-D reconstruction and pigment pattern analyses of some lesions.

  15. Comparison of Lesion Detection and Quantification in MAP Reconstruction with Gaussian and Non-Gaussian Priors

    PubMed Central

    2006-01-01

    Statistical image reconstruction methods based on maximum a posteriori (MAP) principle have been developed for emission tomography. The prior distribution of the unknown image plays an important role in MAP reconstruction. The most commonly used prior are Gaussian priors, whose logarithm has a quadratic form. Gaussian priors are relatively easy to analyze. It has been shown that the effect of a Gaussian prior can be approximated by linear filtering a maximum likelihood (ML) reconstruction. As a result, sharp edges in reconstructed images are not preserved. To preserve sharp transitions, non-Gaussian priors have been proposed. However, their effect on clinical tasks is less obvious. In this paper, we compare MAP reconstruction with Gaussian and non-Gaussian priors for lesion detection and region of interest quantification using computer simulation. We evaluate three representative priors: Gaussian prior, Huber prior, and Geman-McClure prior. We simulate imaging a prostate tumor using positron emission tomography (PET). The detectability of a known tumor in either a fixed background or a random background is measured using a channelized Hotelling observer. The bias-variance tradeoff curves are calculated for quantification of the total tumor activity. The results show that for the detection and quantification tasks, the Gaussian prior is as effective as non-Gaussian priors. PMID:23165056

  16. Female sex steroids and glia cells: Impact on multiple sclerosis lesion formation and fine tuning of the local neurodegenerative cellular network.

    PubMed

    Kipp, Markus; Hochstrasser, Tanja; Schmitz, Christoph; Beyer, Cordian

    2016-08-01

    Multiple sclerosis (MS) is a chronic inflammatory and demyelinating disease that shows a female-to-male gender prevalence and alleviation of disease activity during late stage pregnancy. In MS-related animal models, sex steroids ameliorate symptoms and protect from demyelination and neuronal damage. Underlying mechanisms of these protective avenues are continuously discovered, in part by using novel transgenic animal models. In this review article, we highlight the regulation of glia cell function by female sex steroids. We specifically focus on the relevance of glia cells for immune cell recruitment into the central nervous system and show how estrogen and progesterone can modulate these cell-cell communication pathways. Since MS is considered to have a strong neurodegenerative component, principal neuroprotective mechanisms, exerted by sex-steroids will be discussed as well. Activation of steroid receptors might not just act as immunosuppressant but at the same time harmonize brain-intrinsic networks to dampen neurodegeneration and, thus, disease progression in MS.

  17. Imaging of oxidation-specific epitopes with targeted nanoparticles to detect high-risk atherosclerotic lesions: progress and future directions.

    PubMed

    Briley-Saebo, Karen; Yeang, Calvin; Witztum, Joseph L; Tsimikas, Sotirios

    2014-11-01

    Oxidation-specific epitopes (OSE) within developing atherosclerotic lesions are key antigens that drive innate and adaptive immune responses in atherosclerosis, leading to chronic inflammation. Oxidized phospholipids and malondialdehyde-lysine epitopes are well-characterized OSE present in human atherosclerotic lesions, particularly in pathologically defined vulnerable plaques. Using murine and human OSE-specific antibodies as targeting agents, we have developed radionuclide and magnetic resonance based nanoparticles, containing gadolinium, manganese or lipid-coated ultrasmall superparamagnetic iron oxide, to non-invasively image OSE within experimental atherosclerotic lesions. These methods quantitate plaque burden, allow detection of lesion progression and regression, plaque stabilization, and accumulation of OSE within macrophage-rich areas of the artery wall, suggesting they detect the most active lesions. Future studies will focus on using "natural" antibodies, lipopeptides, and mimotopes for imaging applications. These approaches should enhance the clinical translation of this technique to image, monitor, evaluate efficacy of novel therapeutic agents, and guide optimal therapy of high-risk atherosclerotic lesions. PMID:25297940

  18. Differentiation and quantification of inflammation, demyelination and axon injury or loss in multiple sclerosis.

    PubMed

    Wang, Yong; Sun, Peng; Wang, Qing; Trinkaus, Kathryn; Schmidt, Robert E; Naismith, Robert T; Cross, Anne H; Song, Sheng-Kwei

    2015-05-01

    Axon injury/loss, demyelination and inflammation are the primary pathologies in multiple sclerosis lesions. Despite the prevailing notion that axon/neuron loss is the substrate of clinical progression of multiple sclerosis, the roles that these individual pathological processes play in multiple sclerosis progression remain to be defined. An imaging modality capable to effectively detect, differentiate and individually quantify axon injury/loss, demyelination and inflammation, would not only facilitate the understanding of the pathophysiology underlying multiple sclerosis progression, but also the assessment of treatments at the clinical trial and individual patient levels. In this report, the newly developed diffusion basis spectrum imaging was used to discriminate and quantify the underlying pathological components in multiple sclerosis white matter. Through the multiple-tensor modelling of diffusion weighted magnetic resonance imaging signals, diffusion basis spectrum imaging resolves inflammation-associated cellularity and vasogenic oedema in addition to accounting for partial volume effects resulting from cerebrospinal fluid contamination, and crossing fibres. Quantitative histological analysis of autopsied multiple sclerosis spinal cord specimens supported that diffusion basis spectrum imaging-determined cellularity, axon and myelin injury metrics closely correlated with those pathologies identified and quantified by conventional histological staining. We demonstrated in healthy control subjects that diffusion basis spectrum imaging rectified inaccurate assessments of diffusion properties of white matter tracts by diffusion tensor imaging in the presence of cerebrospinal fluid contamination and/or crossing fibres. In multiple sclerosis patients, we report that diffusion basis spectrum imaging quantitatively characterized the distinct pathologies underlying gadolinium-enhanced lesions, persistent black holes, non-enhanced lesions and non-black hole lesions, a

  19. Differentiation and quantification of inflammation, demyelination and axon injury or loss in multiple sclerosis

    PubMed Central

    Wang, Yong; Sun, Peng; Wang, Qing; Trinkaus, Kathryn; Schmidt, Robert E.; Naismith, Robert T.; Song, Sheng-Kwei

    2015-01-01

    Axon injury/loss, demyelination and inflammation are the primary pathologies in multiple sclerosis lesions. Despite the prevailing notion that axon/neuron loss is the substrate of clinical progression of multiple sclerosis, the roles that these individual pathological processes play in multiple sclerosis progression remain to be defined. An imaging modality capable to effectively detect, differentiate and individually quantify axon injury/loss, demyelination and inflammation, would not only facilitate the understanding of the pathophysiology underlying multiple sclerosis progression, but also the assessment of treatments at the clinical trial and individual patient levels. In this report, the newly developed diffusion basis spectrum imaging was used to discriminate and quantify the underlying pathological components in multiple sclerosis white matter. Through the multiple-tensor modelling of diffusion weighted magnetic resonance imaging signals, diffusion basis spectrum imaging resolves inflammation-associated cellularity and vasogenic oedema in addition to accounting for partial volume effects resulting from cerebrospinal fluid contamination, and crossing fibres. Quantitative histological analysis of autopsied multiple sclerosis spinal cord specimens supported that diffusion basis spectrum imaging-determined cellularity, axon and myelin injury metrics closely correlated with those pathologies identified and quantified by conventional histological staining. We demonstrated in healthy control subjects that diffusion basis spectrum imaging rectified inaccurate assessments of diffusion properties of white matter tracts by diffusion tensor imaging in the presence of cerebrospinal fluid contamination and/or crossing fibres. In multiple sclerosis patients, we report that diffusion basis spectrum imaging quantitatively characterized the distinct pathologies underlying gadolinium-enhanced lesions, persistent black holes, non-enhanced lesions and non-black hole lesions, a

  20. [Tuberous sclerosis].

    PubMed

    Metsähonkala, Liisa; Valanne, Leena; Anttonen, Anna-Kaisa

    2013-01-01

    Tuberous sclerosis is a polymorphic, dominantly inherited syndrome caused by an inactivating mutation in a tumor suppressor gene. The disease involves benign tumors in several distinct organs such as the skin, kidneys, heart and central nervous system. The tumors interfere with organ function, but only some exhibit a significant tendency to grow. The clinical picture of tuberous sclerosis varies from nearly symptomless to a severe disease. Treatment of growing tumors associated with tuberous sclerosis is changing significantly, since their growth can be suppressed with rapamycin and its derivatives. PMID:24159711

  1. Virtopsy -- noninvasive detection of occult bone lesions in postmortem MRI: additional information for traffic accident reconstruction.

    PubMed

    Buck, Ursula; Christe, Andreas; Naether, Silvio; Ross, Steffen; Thali, Michael J

    2009-05-01

    In traffic accidents with pedestrians, cyclists or motorcyclists, patterned impact injuries as well as marks on clothes can be matched to the injury-causing vehicle structure in order to reconstruct the accident and identify the vehicle which has hit the person. Therefore, the differentiation of the primary impact injuries from other injuries is of great importance. Impact injuries can be identified on the external injuries of the skin, the injured subcutaneous and fat tissue, as well as the fractured bones. Another sign of impact is a bone bruise. The bone bruise, or occult bone lesion, means a bleeding in the subcortical bone marrow, which is presumed to be the result of micro-fractures of the medullar trabeculae. The aim of this study was to prove that bleeding in the subcortical bone marrow of the deceased can be detected using the postmortem noninvasive magnetic resonance imaging. This is demonstrated in five accident cases, four involving pedestrians and one a cyclist, where bone bruises were detected in different bones as a sign of impact occurring in the same location as the external and soft tissue impact injuries. PMID:19034476

  2. Contrast-agent-enhanced magnetic resonance imaging: early detection of neoplastic lesions of the CNS

    NASA Astrophysics Data System (ADS)

    Carvlin, Mark J.; Rosa, Louis; Rajan, Sunder S.; Francisco, John

    1991-06-01

    Even though the intrinsic soft tissue contrast sensitivity of magnetic resonance imaging (MRI) affords excellent visualization of anatomic detail, certain pathologic processes may be diagnosed earlier with the administration of a contrast-enhancing agent. At present there is one agent, gadopentetate dimeglumine, GdDTPA, that has received FDA approval for use in the MR scanning of the brain and spine in human patients. This paramagnetic chelate distributes throughout the extracellular fluid space as dictated by capillary permeability so that abnormal vascularity and sites of blood-CNS barrier breakdown are highlighted. Primary neoplastic disease, metastases, meningeal extension, residual and recurrent tumor have been found to be better distinguished in MR images acquired after administration of GdDTPA. Routine administration of GdDTPA for cranial imaging has resulted in the discovery of otherwise occult lesions in approximately 3 of patients. Although the clinical utility and high therapeutic safety index of the first approved magnetic resonance contrast agent, GdDTPA, have been well established, other contrast agents, having different physical, chemical and biological properties, may offer improved sensitivity and bio-specificity. Agents currently being evaluated in vivo include: low osmolal paramagnetic chelates, superparamagnetic particles, metalloporphyrins, liposome encapsulated agents, perfluorocarbons, intravascular macromolecular chelate complexes and labeled monoclonal antibodies. Concurrent with advances in the development of new compounds, innovations in scanning hardware, pulse sequence design and image post-processing are helping to extend the efficacy of contrast media. Additional clinical experience will indicate which contrast agents and which MR techniques can best facilitate the early detection of specific neoplastic lesions.

  3. Multiple sclerosis - resources

    MedlinePlus

    Resources - multiple sclerosis ... The following organizations provide information on multiple sclerosis : Multiple Sclerosis Foundation -- www.msfocus.org National Institute of Neurological Disorders and Stroke -- www.ninds.nih.gov/disorders/multiple_sclerosis National ...

  4. Fully automatic segmentation of multiple sclerosis lesions in brain MR FLAIR images using adaptive mixtures method and Markov random field model.

    PubMed

    Khayati, Rasoul; Vafadust, Mansur; Towhidkhah, Farzad; Nabavi, Massood

    2008-03-01

    In this paper, an approach is proposed for fully automatic segmentation of MS lesions in fluid attenuated inversion recovery (FLAIR) Magnetic Resonance (MR) images. The proposed approach, based on a Bayesian classifier, utilizes the adaptive mixtures method (AMM) and Markov random field (MRF) model to obtain and upgrade the class conditional probability density function (CCPDF) and the a priori probability of each class. To compare the performance of the proposed approach with those of previous approaches including manual segmentation, the similarity criteria of different slices related to 20 MS patients were calculated. Also, volumetric comparison of lesions volume between the fully automated segmentation and the gold standard was performed using correlation coefficient (CC). The results showed a better performance for the proposed approach, compared to those of previous works.

  5. Multimodal coherent anti-Stokes Raman scattering microscopy reveals microglia-associated myelin and axonal dysfunction in multiple sclerosis-like lesions in mice

    NASA Astrophysics Data System (ADS)

    Imitola, Jaime; Côté, Daniel; Rasmussen, Stine; Xie, X. Sunney; Liu, Yingru; Chitnis, Tanuja; Sidman, Richard L.; Lin, Charles. P.; Khoury, Samia J.

    2011-02-01

    Myelin loss and axonal degeneration predominate in many neurological disorders; however, methods to visualize them simultaneously in live tissue are unavailable. We describe a new imaging strategy combining video rate reflectance and fluorescence confocal imaging with coherent anti-Stokes Raman scattering (CARS) microscopy tuned to CH2 vibration of myelin lipids, applied in live tissue of animals with chronic experimental autoimmune encephalomyelitis (EAE). Our method allows monitoring over time of demyelination and neurodegeneration in brain slices with high spatial resolution and signal-to-noise ratio. Local areas of severe loss of lipid signal indicative of demyelination and loss of the reflectance signal from axons were seen in the corpus callosum and spinal cord of EAE animals. Even in myelinated areas of EAE mice, the intensity of myelin lipid signals is significantly reduced. Using heterozygous knock-in mice in which green fluorescent protein replaces the CX3CR1 coding sequence that labels central nervous system microglia, we find areas of activated microglia colocalized with areas of altered reflectance and CARS signals reflecting axonal injury and demyelination. Our data demonstrate the use of multimodal CARS microscopy for characterization of demyelinating and neurodegenerative pathology in a mouse model of multiple sclerosis, and further confirm the critical role of microglia in chronic inflammatory neurodegeneration.

  6. Glycoprotein nonmetastatic melanoma protein B ameliorates skeletal muscle lesions in a SOD1G93A mouse model of amyotrophic lateral sclerosis.

    PubMed

    Nagahara, Yuki; Shimazawa, Masamitsu; Tanaka, Hirotaka; Ono, Yoko; Noda, Yasuhiro; Ohuchi, Kazuki; Tsuruma, Kazuhiro; Katsuno, Masahisa; Sobue, Gen; Hara, Hideaki

    2015-10-01

    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive loss of motor neurons and subsequent muscular atrophy. The quality of life of patients with ALS is significantly improved by ameliorating muscular symptoms. We previously reported that glycoprotein nonmetastatic melanoma protein B (GPNMB; osteoactivin) might serve as a target for ALS therapy. In the present study, superoxide dismutase 1/glycine residue 93 changed to alanine (SOD1(G93A) ) transgenic mice were used as a model of ALS. Expression of the C-terminal fragment of GPNMB was increased in the skeletal muscles of SOD1(G93A) mice and patients with sporadic ALS. SOD1(G93A) /GPNMB transgenic mice were generated to determine whether GPNMB expression ameliorates muscular symptoms. The weight and cross-sectional area of the gastrocnemius muscle, number and cross-sectional area of myofibers, and denervation of neuromuscular junctions were ameliorated in SOD1(G93A) /GPNMB vs. SOD1(G93A) mice. Furthermore, direct injection of a GPNMB expression plasmid into the gastrocnemius muscle of SOD1(G93A) mice increased the numbers of myofibers and prevented myofiber atrophy. These findings suggest that GPNMB directly affects skeletal muscle and prevents muscular pathology in SOD1(G93A) mice and may therefore serve as a target for therapy of ALS.

  7. On the relationship of minimum detectable contrast to dose and lesion size in abdominal CT

    NASA Astrophysics Data System (ADS)

    Zhou, Yifang; Scott, Alexander, II; Allahverdian, Janet; Lee, Christina; Kightlinger, Blake; Azizyan, Avetis; Miller, Joseph

    2015-10-01

    CT dose optimization is typically guided by pixel noise or contrast-to-noise ratio that does not delineate low contrast details adequately. We utilized the statistically defined low contrast detectability to study its relationship to dose and lesion size in abdominal CT. A realistically shaped medium sized abdomen phantom was customized to contain a cylindrical void of 4 cm diameter. The void was filled with a low contrast (1% and 2%) insert containing six groups of cylindrical targets ranging from 1.2 mm to 7 mm in size. Helical CT scans were performed using a Siemens 64-slice mCT and a GE Discovery 750 HD at various doses. After the subtractions between adjacent slices, the uniform sections of the filtered backprojection reconstructed images were partitioned to matrices of square elements matching the sizes of the targets. It was verified that the mean values from all the elements in each matrix follow a Gaussian distribution. The minimum detectable contrast (MDC), quantified by the mean signal to background difference equal to the distribution’s standard deviation multiplied by 3.29, corresponding to 95% confidence level, was found to be related to the phantom specific dose and the element size by a power law (R^2  >  0.990). Independent readings on the 5 mm and 7 mm targets were compared to the measured contrast to the MDC ratios. The results showed that 93% of the cases were detectable when the measured contrast exceeds the MDC. The correlation of the MDC to the pixel noise and target size was also identified and the relationship was found to be the same for the scanners in the study. To quantify the impact of iterative reconstructions to the low contrast detectability, the noise structure was studied in a similar manner at different doses and with different ASIR blending fractions. The relationship of the dose to the blending fraction and low contrast detectability is presented.

  8. Stretchable Electrochemical Impedance Sensors for Intravascular Detection of Lipid-Rich Lesions in New Zealand White Rabbits

    PubMed Central

    Cao, Hung; Yu, Fei; Zhao, Yu; Scianmarello, Nick; Lee, Juhyun; Dai, Wangde; Jen, Nelson; Beebe, Tyler; Li, Rongsong; Ebrahimi, Ramin; Chang, Donald S.; Mody, Freny V.; Pacella, John; Tai, Yu-Chong; Hsiai, Tzung

    2014-01-01

    Flexible electronics have enabled catheter-based intravascular sensing. However, real-time interrogation of unstable plaque remains an unmet clinical challenge. Here, we demonstrate the feasibility of stretchable electrochemical impedance spectroscopy (EIS) sensors for endoluminal investigations in New Zealand White (NZW) rabbits on diet-induced hyperlipidemia. A parylene C (PAC)-based EIS sensor mounted on the surface of an inflatable silicone balloon affixed to the tip of an interrogating catheter was deployed 1) on the explants of NZW rabbit aorta for detection of lipid-rich atherosclerotic lesions, and 2) on live animals for demonstration of balloon inflation and EIS measurements. An input peak-to-peak AC voltage of 10 mV and sweeping-frequency from 300 kHz to 100 Hz were delivered to the endoluminal sites. Balloon inflation allowed EIS sensors to be in contact with endoluminal surface. In the oxidized low-density-lipoprotein (oxLDL)-rich lesions from explants of fat-fed rabbits, impedance magnitude increased significantly by 1.5-fold across the entire frequency band, and phase shifted ~5 degrees at frequencies below 10 kHz. In the lesion-free sites of the normal diet-fed rabbits, impedance magnitude increased by 1.2-fold and phase shifted ~5 degrees at frequencies above 30 kHz. Thus, we demonstrate the feasibility of stretchable intravascular EIS sensors for identification of lipid rich lesions, with a translational implication for detecting unstable lesions. PMID:24333932

  9. Detection of benign proliferative lesions on vocal cords with voice handicap index.

    PubMed

    Huang, Xuekun; Zhang, Gehua; Liu, Xiujin; Wang, Tao; Zhu, Ling

    2012-10-01

    The aim of this study was to investigate the significance and practical applicability of the voice handicap index (VHI) in the diagnosis of benign proliferative lesions of the vocal cords (BLVCs). The detection of VHI included the calculation of functional (F), physical (P) and emotional (E) domains, and the score of each domain and total score (TVH). The VHI was scored in patients with BLVCs and healthy controls. Eighty-four patients with BLVCs and 27 healthy controls were enrolled in the present study. The F, P, E and TVH scores were 10.40±7.84, 19.88±8.81, 9.39±8.49 and 39.37±21.83, respectively, in the BLVC group and 0.78±0.97, 0.85±1.06, 0.26±0.72 and 1.89±2.31, respectively, in the control group. A significant difference was found between the two groups (P<0. 01). The daily duration of speech and course of BLVCs did not correlate with the VHI score in BLVC patients (P>0.05). There was no marked difference in the VHI score between voice-consuming and non-voice consuming occupations (P>0.05) or between males and females (P>0.05). In BLVC patients, VHI may subjectively express the voice handicap, while daily duration of speech, course of BLVC, occupation and gender have no impact on VHI.

  10. Consortium for Molecular Characterization of Screen-Detected Lesions Created: Eight Grants Awarded | Division of Cancer Prevention

    Cancer.gov

    The NCI has awarded eight grants to create the Consortium for Molecular Characterization of Screen-Detected Lesions. The consortium has seven molecular characterization laboratories (MCLs) and a coordinating center, and is supported by the Division of Cancer Prevention and the Division of Cancer Biology. | 7 laboratories and a coordinating center focused on identifying screening-detected pre-cancers and early cancers, including within the tumor microenvironment.

  11. Detection of atherosclerotic lesions and intimal macrophages using CD36-targeted nanovesicles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current approaches to the diagnosis and therapy of atherosclerosis cannot target to lesion-determinant cells in the artery wall. Intimal macrophage infiltration promotes atherosclerotic lesion development by facilitating the accumulation of oxidized low-density lipoproteins (oxLDL) and increasing in...

  12. Tissue resonance interaction accurately detects colon lesions: A double-blind pilot study

    PubMed Central

    Dore, Maria P; Tufano, Marcello O; Pes, Giovanni M; Cuccu, Marianna; Farina, Valentina; Manca, Alessandra; Graham, David Y

    2015-01-01

    AIM: To investigated the performance of the tissue resonance interaction method (TRIM) for the non-invasive detection of colon lesions. METHODS: We performed a prospective single-center blinded pilot study of consecutive adults undergoing colonoscopy at the University Hospital in Sassari, Italy. Before patients underwent colonoscopy, they were examined by the TRIMprobe which detects differences in electromagnetic properties between pathological and normal tissues. All patients had completed the polyethylene glycol-containing bowel prep for the colonoscopy procedure before being screened. During the procedure the subjects remained fully dressed. A hand-held probe was moved over the abdomen and variations in electromagnetic signals were recorded for 3 spectral lines (462-465 MHz, 930 MHz, and 1395 MHz). A single investigator, blind to any clinical information, performed the test using the TRIMprob system. Abnormal signals were identified and recorded as malignant or benign (adenoma or hyperplastic polyps). Findings were compared with those from colonoscopy with histologic confirmation. Statistical analysis was performed by χ2 test. RESULTS: A total of 305 consecutive patients fulfilling the inclusion criteria were enrolled over a period of 12 months. The most frequent indication for colonoscopy was abdominal pain (33%). The TRIMprob was well accepted by all patients; none spontaneously complained about the procedure, and no adverse effects were observed. TRIM proved inaccurate for polyp detection in patients with inflammatory bowel disease (IBD) and they were excluded leaving 281 subjects (mean age 59 ± 13 years; 107 males). The TRIM detected and accurately characterized all 12 adenocarcinomas and 135/137 polyps (98.5%) including 64 adenomatous (100%) found. The method identified cancers and polyps with 98.7% sensitivity, 96.2% specificity, and 97.5% diagnostic accuracy, compared to colonoscopy and histology analyses. The positive predictive value was 96.7% and the

  13. Analysis of Lymphocytic DNA Damage in Early Multiple Sclerosis by Automated Gamma-H2AX and 53BP1 Foci Detection: A Case Control Study

    PubMed Central

    Rasche, Ludwig; Heiserich, Lisa; Behrens, Janina Ruth; Lenz, Klaus; Pfuhl, Catherina; Wakonig, Katharina; Gieß, René Markus; Freitag, Erik; Eberle, Caroline; Wuerfel, Jens; Dörr, Jan; Bauer, Peter; Bellmann-Strobl, Judith; Paul, Friedemann; Roggenbuck, Dirk; Ruprecht, Klemens

    2016-01-01

    Background In response to DNA double-strand breaks, the histone protein H2AX becomes phosphorylated at its C-terminal serine 139 residue, referred to as γ-H2AX. Formation of γ-H2AX foci is associated with recruitment of p53-binding protein 1 (53BP1), a regulator of the cellular response to DNA double-strand breaks. γ-H2AX expression in peripheral blood mononuclear cells (PBMCs) was recently proposed as a diagnostic and disease activity marker for multiple sclerosis (MS). Objective To evaluate the significance of γ-H2AX and 53BP1 foci in PBMCs as diagnostic and disease activity markers in patients with clinically isolated syndrome (CIS) and early relapsing-remitting MS (RRMS) using automated γ-H2AX and 53BP1 foci detection. Methods Immunocytochemistry was performed on freshly isolated PBMCs of patients with CIS/early RRMS (n = 25) and healthy controls (n = 27) with γ-H2AX and 53BP1 specific antibodies. Nuclear γ-H2AX and 53BP1 foci were determined using a fully automated reading system, assessing the numbers of γ-H2AX and 53BP1 foci per total number of cells and the percentage of cells with foci. Patients underwent contrast enhanced 3 Tesla magnetic resonance imaging (MRI) and clinical examination including expanded disability status scale (EDSS) score. γ-H2AX and 53BP1 were also compared in previously frozen PBMCs of each 10 CIS/early RRMS patients with and without contrast enhancing lesions (CEL) and 10 healthy controls. Results The median (range) number of γ-H2AX (0.04 [0–0.5]) and 53BP1 (0.005 [0–0.2]) foci per cell in freshly isolated PBMCs across all study participants was low and similar to previously reported values of healthy individuals. For both, γ-H2AX and 53BP1, the cellular focus number as well as the percentage of positive cells did not differ between patients with CIS/RRMS and healthy controls. γ-H2AX and 53BP1 levels neither correlated with number nor volume of T2-weighted lesions on MRI, nor with the EDSS. Although γ-H2AX, but not

  14. A computer simulation study comparing lesion detection accuracy with digital mammography, breast tomosynthesis, and cone-beam CT breast imaging

    SciTech Connect

    Gong Xing; Glick, Stephen J.; Liu, Bob; Vedula, Aruna A.; Thacker, Samta

    2006-04-15

    Although conventional mammography is currently the best modality to detect early breast cancer, it is limited in that the recorded image represents the superposition of a three-dimensional (3D) object onto a 2D plane. Recently, two promising approaches for 3D volumetric breast imaging have been proposed, breast tomosynthesis (BT) and CT breast imaging (CTBI). To investigate possible improvements in lesion detection accuracy with either breast tomosynthesis or CT breast imaging as compared to digital mammography (DM), a computer simulation study was conducted using simulated lesions embedded into a structured 3D breast model. The computer simulation realistically modeled x-ray transport through a breast model, as well as the signal and noise propagation through a CsI based flat-panel imager. Polyenergetic x-ray spectra of Mo/Mo 28 kVp for digital mammography, Mo/Rh 28 kVp for BT, and W/Ce 50 kVp for CTBI were modeled. For the CTBI simulation, the intensity of the x-ray spectra for each projection view was determined so as to provide a total average glandular dose of 4 mGy, which is approximately equivalent to that given in conventional two-view screening mammography. The same total dose was modeled for both the DM and BT simulations. Irregular lesions were simulated by using a stochastic growth algorithm providing lesions with an effective diameter of 5 mm. Breast tissue was simulated by generating an ensemble of backgrounds with a power law spectrum, with the composition of 50% fibroglandular and 50% adipose tissue. To evaluate lesion detection accuracy, a receiver operating characteristic (ROC) study was performed with five observers reading an ensemble of images for each case. The average area under the ROC curves (A{sub z}) was 0.76 for DM, 0.93 for BT, and 0.94 for CTBI. Results indicated that for the same dose, a 5 mm lesion embedded in a structured breast phantom was detected by the two volumetric breast imaging systems, BT and CTBI, with statistically

  15. A simulator for evaluating methods for the detection of lesion-deficit associations

    NASA Technical Reports Server (NTRS)

    Megalooikonomou, V.; Davatzikos, C.; Herskovits, E. H.

    2000-01-01

    Although much has been learned about the functional organization of the human brain through lesion-deficit analysis, the variety of statistical and image-processing methods developed for this purpose precludes a closed-form analysis of the statistical power of these systems. Therefore, we developed a lesion-deficit simulator (LDS), which generates artificial subjects, each of which consists of a set of functional deficits, and a brain image with lesions; the deficits and lesions conform to predefined distributions. We used probability distributions to model the number, sizes, and spatial distribution of lesions, to model the structure-function associations, and to model registration error. We used the LDS to evaluate, as examples, the effects of the complexities and strengths of lesion-deficit associations, and of registration error, on the power of lesion-deficit analysis. We measured the numbers of recovered associations from these simulated data, as a function of the number of subjects analyzed, the strengths and number of associations in the statistical model, the number of structures associated with a particular function, and the prior probabilities of structures being abnormal. The number of subjects required to recover the simulated lesion-deficit associations was found to have an inverse relationship to the strength of associations, and to the smallest probability in the structure-function model. The number of structures associated with a particular function (i.e., the complexity of associations) had a much greater effect on the performance of the analysis method than did the total number of associations. We also found that registration error of 5 mm or less reduces the number of associations discovered by approximately 13% compared to perfect registration. The LDS provides a flexible framework for evaluating many aspects of lesion-deficit analysis.

  16. Skin lesion-associated pathogens from Octopus vulgaris: first detection of Photobacterium swingsii, Lactococcus garvieae and betanodavirus.

    PubMed

    Fichi, G; Cardeti, G; Perrucci, S; Vanni, A; Cersini, A; Lenzi, C; De Wolf, T; Fronte, B; Guarducci, M; Susini, F

    2015-07-23

    The common octopus Octopus vulgaris Cuvier, 1798 is extremely important in fisheries and is a useful protein source in most Mediterranean countries. Here we investigated pathogens associated with skin lesions in 9 naturally deceased specimens that included both cultured and wild common octopus. Within 30 min after death, each octopus was stored at 4°C and microbiologically examined within 24 h. Bacterial colonies, cultured from swabs taken from the lesions, were examined using taxonomical and biochemical analyses. Vibrio alginolyticus and V. parahaemolyticus were only isolated from cultured animals. A conventional PCR targeting the 16S ribosomal RNA (rRNA) gene and sequencing were performed on 2 bacterial isolates that remained unidentified after taxonomical and biochemical analysis. The sequence results indicated that the bacteria had a 99% identity with Lactococcus garvieae and Photobacterium swingsii. L. garvieae was confirmed using a specific PCR based on the 16S-23S rRNA internal transcribed spacer region, while P. swingsii was confirmed by phylogenetic analyses. Although all animals examined were found to be infected by the protozoan species Aggregata octopiana localised in the intestines, it was also present in skin lesions of 2 of the animals. Betanodavirus was detected in both cultured and wild individuals by cell culture, PCR and electron microscopy. These findings are the first report of L. garvieae and betanodavirus from skin lesions of common octopus and the first identification of P. swingsii both in octopus skin lesions and in marine invertebrates in Italy. PMID:26203886

  17. Skin lesion-associated pathogens from Octopus vulgaris: first detection of Photobacterium swingsii, Lactococcus garvieae and betanodavirus.

    PubMed

    Fichi, G; Cardeti, G; Perrucci, S; Vanni, A; Cersini, A; Lenzi, C; De Wolf, T; Fronte, B; Guarducci, M; Susini, F

    2015-07-23

    The common octopus Octopus vulgaris Cuvier, 1798 is extremely important in fisheries and is a useful protein source in most Mediterranean countries. Here we investigated pathogens associated with skin lesions in 9 naturally deceased specimens that included both cultured and wild common octopus. Within 30 min after death, each octopus was stored at 4°C and microbiologically examined within 24 h. Bacterial colonies, cultured from swabs taken from the lesions, were examined using taxonomical and biochemical analyses. Vibrio alginolyticus and V. parahaemolyticus were only isolated from cultured animals. A conventional PCR targeting the 16S ribosomal RNA (rRNA) gene and sequencing were performed on 2 bacterial isolates that remained unidentified after taxonomical and biochemical analysis. The sequence results indicated that the bacteria had a 99% identity with Lactococcus garvieae and Photobacterium swingsii. L. garvieae was confirmed using a specific PCR based on the 16S-23S rRNA internal transcribed spacer region, while P. swingsii was confirmed by phylogenetic analyses. Although all animals examined were found to be infected by the protozoan species Aggregata octopiana localised in the intestines, it was also present in skin lesions of 2 of the animals. Betanodavirus was detected in both cultured and wild individuals by cell culture, PCR and electron microscopy. These findings are the first report of L. garvieae and betanodavirus from skin lesions of common octopus and the first identification of P. swingsii both in octopus skin lesions and in marine invertebrates in Italy.

  18. Fusion of classifiers for REIS-based detection of suspicious breast lesions

    NASA Astrophysics Data System (ADS)

    Lederman, Dror; Wang, Xingwei; Zheng, Bin; Sumkin, Jules H.; Tublin, Mitchell; Gur, David

    2011-03-01

    After developing a multi-probe resonance-frequency electrical impedance spectroscopy (REIS) system aimed at detecting women with breast abnormalities that may indicate a developing breast cancer, we have been conducting a prospective clinical study to explore the feasibility of applying this REIS system to classify younger women (< 50 years old) into two groups of "higher-than-average risk" and "average risk" of having or developing breast cancer. The system comprises one central probe placed in contact with the nipple, and six additional probes uniformly distributed along an outside circle to be placed in contact with six points on the outer breast skin surface. In this preliminary study, we selected an initial set of 174 examinations on participants that have completed REIS examinations and have clinical status verification. Among these, 66 examinations were recommended for biopsy due to findings of a highly suspicious breast lesion ("positives"), and 108 were determined as negative during imaging based procedures ("negatives"). A set of REIS-based features, extracted using a mirror-matched approach, was computed and fed into five machine learning classifiers. A genetic algorithm was used to select an optimal subset of features for each of the five classifiers. Three fusion rules, namely sum rule, weighted sum rule and weighted median rule, were used to combine the results of the classifiers. Performance evaluation was performed using a leave-one-case-out cross-validation method. The results indicated that REIS may provide a new technology to identify younger women with higher than average risk of having or developing breast cancer. Furthermore, it was shown that fusion rule, such as a weighted median fusion rule and a weighted sum fusion rule may improve performance as compared with the highest performing single classifier.

  19. Computer aided automatic detection of malignant lesions in diffuse optical mammography

    PubMed Central

    Busch, David R.; Guo, Wensheng; Choe, Regine; Durduran, Turgut; Feldman, Michael D.; Mies, Carolyn; Rosen, Mark A.; Schnall, Mitchell D.; Czerniecki, Brian J.; Tchou, Julia; DeMichele, Angela; Putt, Mary E.; Yodh, Arjun G.

    2010-01-01

    Purpose: Computer aided detection (CAD) data analysis procedures are introduced and applied to derive composite diffuse optical tomography (DOT) signatures of malignancy in human breast tissue. In contrast to previous optical mammography analysis schemes, the new statistical approach utilizes optical property distributions across multiple subjects and across the many voxels of each subject. The methodology is tested in a population of 35 biopsy-confirmed malignant lesions. Methods: DOT CAD employs multiparameter, multivoxel, multisubject measurements to derive a simple function that transforms DOT images of tissue chromophores and scattering into a probability of malignancy tomogram. The formalism incorporates both intrasubject spatial heterogeneity and intersubject distributions of physiological properties derived from a population of cancer-containing breasts (the training set). A weighted combination of physiological parameters from the training set define a malignancy parameter (M), with the weighting factors optimized by logistic regression to separate training-set cancer voxels from training-set healthy voxels. The utility of M is examined, employing 3D DOT images from an additional subjects (the test set). Results: Initial results confirm that the automated technique can produce tomograms that distinguish healthy from malignant tissue. When compared to a gold standard tissue segmentation, this protocol produced an average true positive rate (sensitivity) of 89% and a true negative rate (specificity) of 94% using an empirically chosen probability threshold. Conclusions: This study suggests that the automated multisubject, multivoxel, multiparameter statistical analysis of diffuse optical data is potentially quite useful, producing tomograms that distinguish healthy from malignant tissue. This type of data analysis may also prove useful for suppression of image artifacts. PMID:20443506

  20. Upgrade of high-risk breast lesions detected on mammography in the Breast Cancer Surveillance Consortium

    PubMed Central

    Menes, Tehillah S.; Rosenberg, Robert; Balch, Steven; Jaffer, Shabnam; Kerlikowske, Karla; Miglioretti, Diana L.

    2013-01-01

    Background Upgrade rates of high-risk breast lesions after screening mammography were examined. Study design The Breast Cancer Surveillance Consortium registry was used to identify all BI-RADS 4 assessments followed by needle biopsies with high-risk lesions. Follow-up was performed for all women. Results High-risk lesions were found in 957 needle biopsies, with excision documented in 53%. Most (N=685) were atypical ductal hyperplasia (ADH), 173 were lobular neoplasia, and 99 were papillary lesions. Upgrade to cancer varied with type of lesion (18% in ADH, 10% in lobular neoplasia and 2% in papillary). In premenopausal women with ADH, upgrade was associated with family history. Cancers associated with ADH were mostly (82%) ductal carcinoma in situ, those associated with lobular neoplasia were mostly (56%) invasive. During further 2 years of follow-up, cancer was documented in 1% of women with follow-up surgery and in 3% with no surgery. Conclusion Despite low rates of surgery, low rates of cancer were documented during follow-up. Benign papillary lesions diagnosed on BI-RADS 4 mammograms among asymptomatic women do not justify surgical excision. PMID:24112677

  1. In vitro evaluation of the efficacy of laser fluorescence (DIAGNOdent) to detect demineralization and remineralization of smooth enamel lesions

    PubMed Central

    Bahrololoomi, Zahra; Musavi, Seyed Ahmad; Kabudan, Mona

    2013-01-01

    Objective: Early detection of smooth surface lesions is important for appropriate management and monitoring of dental caries. The purpose of this in vitro study was to evaluate the efficacy of laser fluorescence to detect demineralization and remineralization of smooth enamel surfaces. Materials and Methods: In this in vitro study, 132 enamel blocks of semi-impacted human third molars were obtained; artificial caries lesions were induced and they were submitted to the pH-cycling process to create remineralization. Superficial microhardness (SMH) and laser fluorescence (LF) analysis were performed at baseline, after demineralization, and remineralization processes. The data were analyzed by Statistical Package for Social Sciences (SPSS)-16 using analysis of variance (ANOVA), Paired samples t-test, and Pearson's correlation test. Results: There was a significant difference between SMH values at baseline, after demineralization and after remineralization. Also, a statistically significant difference was observed between LF values in these three stages. The LF values increased after demineralization and then decreased after remineralization, and the SMH values decreased after demineralization and increased after remineralization. There was an inverse relationship between SMH and LF only at baseline and after demineralization, but not after remineralization. Conclusion: The results showed that LF is an appropriate method for detection of demineralization in an in vitro condition in smooth enamel lesions, but it was not so efficient in the detection of remineralization. PMID:23956542

  2. Immunology of Multiple Sclerosis.

    PubMed

    Sospedra, Mireia; Martin, Roland

    2016-04-01

    Multiple sclerosis (MS) is considered a prototypic autoimmune disease of the central nervous system (CNS). A complex genetic background with the HLA-DR15 haplotype as the main genetic risk factor and over 100 mostly immune-related minor risk alleles as well as several environmental factors contribute to the etiology of MS. With respect to pathomechanisms, autoimmune inflammation in early MS is primarily mediated by adaptive immune responses and involves autoreactive T cells, B cells, and antibodies, while the later, chronic stages of MS are characterized by a compartmentalized immune response in the CNS with activated microglia and macrophages. A host of immune cells and mediators can contribute to the autoimmune process, but CNS-related factors such as localization of lesions, vulnerability of oligodendrocytes, neurons/axons, and secondary metabolic changes all play a role in the heterogeneous expression of the disease, including different pathologic lesion patterns, neuroimaging findings, disease courses, and severity and response to treatment. PMID:27116718

  3. Clinical impact of time-of-flight and point response modeling in PET reconstructions: a lesion detection study

    NASA Astrophysics Data System (ADS)

    Schaefferkoetter, Joshua; Casey, Michael; Townsend, David; El Fakhri, Georges

    2013-03-01

    Time-of-flight (TOF) and point spread function (PSF) modeling have been shown to improve PET reconstructions, but the impact on physicians in the clinical setting has not been thoroughly investigated. A lesion detection and localization study was performed using simulated lesions in real patient images. Four reconstruction schemes were considered: ordinary Poisson OSEM (OP) alone and combined with TOF, PSF, and TOF + PSF. The images were presented to physicians experienced in reading PET images, and the performance of each was quantified using localization receiver operating characteristic. Numerical observers (non-prewhitening and Hotelling) were used to identify optimal reconstruction parameters, and observer SNR was compared to the performance of the physicians. The numerical models showed good agreement with human performance, and best performance was achieved by both when using TOF + PSF. These findings suggest a large potential benefit of TOF + PSF for oncology PET studies, especially in the detection of small, low-intensity, focal disease in larger patients.

  4. Photodynamic detection in visualisation of cutaneous and oral mucosa premalignant and malignant lesions: two clinical cases

    NASA Astrophysics Data System (ADS)

    Jurczyszyn, Kamil; Ziólkowski, Piotr; Osiecka, Beata; Gerber, Hanna; Dziedzic, Magdalena

    2008-11-01

    Photodynamic diagnosis (PDD) is promising method of visualisation of premalignant and malignant lesions. PDD is consisted of two main agents: special chemical compound which is called photosensitizer and light. Photosensitizer has affinity to fast proliferating cells such as pre- or malignant. During light irradiation (with proper wavelength - corresponding to absorption peak of photosensitizer) photosensitizer gains energy and passes into excited singlet state S1. Returning to basic singlet state Sn, leads to fluorescence. Due to difference between concentration of photosensitizer in lesion and normal tissue it is possible to obtain high contrast image of lesion. Case #1: 53 years old woman with basal cell carcinoma (BCC) in nasal region; 20% delta-aminolevulinic acid as a precursor of photosensitizer on eucerin base was used. Case #2: 57 years old woman with multifocal oral leukoplakia on cheek mucosa and tongue; 2% chlorophyll gel as photosesitizer was used. All photographs were taken in white light without any filter and in blue and UV light with orange filter: in both cases the total area of the lesions appeared to be larger than it has been clinically observed. Thus, the PDD might be helpful in evaluation of margins of surgical excision of such lesions.

  5. Multiple Sclerosis.

    ERIC Educational Resources Information Center

    Plummer, Nancy; Michael, Nancy, Ed.

    This module on multiple sclerosis is intended for use in inservice or continuing education programs for persons who administer medications in long-term care facilities. Instructor information, including teaching suggestions, and a listing of recommended audiovisual materials and their sources appear first. The module goal and objectives are then…

  6. A comparison of lesion detection accuracy using digital mammography and flat-panel CT breast imaging (Honorable Mention Poster Award)

    NASA Astrophysics Data System (ADS)

    Gong, Xing; Vedula, Aruna A.; Thacker, Samta; Glick, Stephen J.

    2005-04-01

    Although conventional mammography is currently the best modality to detect early breast cancer, it is limited in that the recorded image represents the superposition of a 3D object onto a 2D plane. As an alternative, cone-beam CT breast imaging with a CsI based flat-panel imager (CTBI) has been proposed with the ability to provide 3D visualization of breast tissue. To investigate possible improvements in lesion detection accuracy using CTBI over digital mammography (DM), a computer simulation study was conducted using simulated lesions embedded into a structured 3D breast model. The computer simulation realistically modeled x-ray transport through a breast model, as well as the signal and noise propagation through the flat-panel imager. Polyenergetic x-ray spectra of W/Al 50 kVp for CTBI and Mo/Mo 28 kVp for DM were modeled. For the CTBI simulation, the intensity of the x-ray spectra for each projection view was determined so as to provide a total mean glandular dose (MGD) of 4 mGy, which is approximately equivalent to that given in a conventional two-view screening mammography study. Since only one DM view was investigated here, the intensity of the DM x-ray spectra was defined to give 2 mGy MGD. Irregular lesions were simulated by using a stochastic growth algorithm providing lesions with an effective diameter of 5 mm. Breast tissue was simulated by generating an ensemble of backgrounds with a power law spectrum. To evaluate lesion detection accuracy, a receiver operating characteristic (ROC) study was performed with 4 observers reading an ensemble of images for each case. The average area under the ROC curves (Az) was 0.94 for CTBI, and 0.81 for DM. Results indicate that a 5 mm lesion embedded in a structured breast phantom can be detected by CT breast imaging with statistically significant higher confidence than with digital mammography.

  7. Influence of moisture and plaque on the performance of a laser fluorescence device in detecting caries lesions in primary teeth.

    PubMed

    Bittar, Daniela G; Gimenez, Thaís; Morais, Caroline C; De Benedetto, Monique S; Braga, Mariana M; Mendes, Fausto Medeiros

    2012-11-01

    The aim of this study was to evaluate the influence of dental plaque and moisture on performance of a laser fluorescence device in detecting occlusal and proximal caries lesions in primary teeth. Fifty-five occlusal and 58 proximal sites on primary molars were evaluated using a DIAGNOdent pen (LFpen) device. For the drying time study, the evaluations were performed in: (I) moist teeth; (II) teeth dried for 3 s, or (III) dried for 15 s. For the plaque study, the evaluations were done in sites: (I) without plaque; (II) with plaque, and (III) after cleaning. Evaluation of the teeth sections in stereomicroscope was the reference standard method. LF pen values, sensitivity, specificity, and accuracy were compared. The values obtained after 15 s of drying were higher than those obtained with moist teeth or dried for 3 s at both occlusal and proximal surfaces. However, there was no change in the performance in detecting caries lesions. With regard to the presence of plaque, there was no significant change in the readings of the device, but specificity was decreased in occlusal surfaces with plaque. At proximal surfaces, however, no significant differences were observed. In conclusion, the moisture conditions do not influence significantly the performance of the LFpen, but the presence of plaque can affect its performance in detecting occlusal caries lesions in primary teeth.

  8. Clinical relevance of studies on the accuracy of visual inspection for detecting caries lesions: a systematic review.

    PubMed

    Gimenez, Thais; Piovesan, Chaiana; Braga, Mariana M; Raggio, Daniela P; Deery, Chris; Ricketts, David N; Ekstrand, Kim R; Mendes, Fausto Medeiros

    2015-01-01

    Although visual inspection is the most commonly used method for caries detection, and consequently the most investigated, studies have not been concerned about the clinical relevance of this procedure. Therefore, we conducted a systematic review in order to perform a critical evaluation considering the clinical relevance and methodological quality of studies on the accuracy of visual inspection for assessing caries lesions. Two independent reviewers searched several databases through July 2013 to identify papers/articles published in English. Other sources were checked to identify unpublished literature. The eligible studies were those which (1) assessed the accuracy of the visual method for detecting caries lesions on occlusal, approximal or smooth surfaces, in primary or permanent teeth, (2) used a reference standard, and (3) reported data about sample size and accuracy of the methods. Aspects related to clinical relevance and the methodological quality of the studies were evaluated. 96 of the 5,578 articles initially identified met the inclusion criteria. In general, most studies failed in considering some clinically relevant aspects: only 1 included study validated activity status of lesions, no study considered its prognosis, 79 studies did not consider a clinically relevant outcome, and only 1 evaluated a patient-centred outcome. Concerning methodological quality, the majority of the studies presented a high risk of bias in sample selection. In conclusion, studies on the accuracy of the visual method for caries detection should consider clinically relevant outcomes besides accuracy; moreover, they should be conducted with higher methodological quality, mainly regarding sample selection.

  9. Hippocampal Sclerosis: Causes and Prevention.

    PubMed

    Walker, Matthew Charles

    2015-06-01

    Hippocampal sclerosis is the commonest cause of drug-resistant epilepsy in adults, and is associated with alterations to structures and networks beyond the hippocampus.In addition to being a cause of epilepsy, the hippocampus is vulnerable to damage from seizure activity. In particular, prolonged seizures (status epilepticus) can result in hippocampal sclerosis. The hippocampus is also vulnerable to other insults including traumatic brain injury, and inflammation. Hippocampal sclerosis can occur in association with other brain lesions; the prevailing view is that it is probably a secondary consequence. In such instances, successful surgical treatment usually involves the resection of both the lesion and the involved hippocampus. Experimental data have pointed to numerous neuroprotective strategies to prevent hippocampal sclerosis. Initial neuroprotective strategies aimed at glutamate receptors may be effective, but later, metabolic pathways, apoptosis, reactive oxygen species, and inflammation are involved, perhaps necessitating the use of interventions aimed at multiple targets. Some of the therapies that we use to treat status epilepticus may neuroprotect. However, prevention of neuronal death does not necessarily prevent the later development of epilepsy or cognitive deficits. Perhaps, the most important intervention is the early, aggressive treatment of seizure activity, and the prevention of prolonged seizures. PMID:26060898

  10. Detection of retinal lesions in diabetic retinopathy: comparative evaluation of 7-field digital color photography versus red-free photography.

    PubMed

    Venkatesh, Pradeep; Sharma, Reetika; Vashist, Nagender; Vohra, Rajpal; Garg, Satpal

    2015-10-01

    Red-free light allows better detection of vascular lesions as this wavelength is absorbed by hemoglobin; however, the current gold standard for the detection and grading of diabetic retinopathy remains 7-field color fundus photography. The goal of this study was to compare the ability of 7-field fundus photography using red-free light to detect retinopathy lesions with corresponding images captured using standard 7-field color photography. Non-stereoscopic standard 7-field 30° digital color fundus photography and 7-field 30° digital red-free fundus photography were performed in 200 eyes of 103 patients with various grades of diabetic retinopathy ranging from mild to moderate non-proliferative diabetic retinopathy to proliferative diabetic retinopathy. The color images (n = 1,400) were studied with corresponding red-free images (n = 1,400) by one retina consultant (PV) and two senior residents training in retina. The various retinal lesions [microaneurysms, hemorrhages, hard exudates, soft exudates, intra-retinal microvascular anomalies (IRMA), neovascularization of the retina elsewhere (NVE), and neovascularization of the disc (NVD)] detected by all three observers in each of the photographs were noted followed by determination of agreement scores using κ values (range 0-1). Kappa coefficient was categorized as poor (≤0), slight (0.01-0.20), fair (0.2 -0.40), moderate (0.41-0.60), substantial (0.61-0.80), and almost perfect (0.81-1). The number of lesions detected by red-free images alone was higher for all observers and all abnormalities except hard exudates. Detection of IRMA was especially higher for all observers with red-free images. Between image pairs, there was substantial agreement for detection of hard exudates (average κ = 0.62, range 0.60-0.65) and moderate agreement for detection of hemorrhages (average κ = 0.52, range 0.45-0.58), soft exudates (average κ = 0.51, range 0.42-0.61), NVE (average κ = 0.47, range 0.39-0.53), and NVD

  11. Use of electrical impedance spectroscopy to detect malignant and potentially malignant oral lesions

    PubMed Central

    Murdoch, Craig; Brown, Brian H; Hearnden, Vanessa; Speight, Paul M; D’Apice, Katy; Hegarty, Anne M; Tidy, John A; Healey, T Jamie; Highfield, Peter E; Thornhill, Martin H

    2014-01-01

    The electrical properties of tissues depend on their architecture and cellular composition. We have previously shown that changes in electrical impedance can be used to differentiate between different degrees of cervical dysplasia and cancer of the cervix. In this proof-of-concept study, we aimed to determine whether electrical impedance spectroscopy (EIS) could distinguish between normal oral mucosa; benign, potentially malignant lesions (PML); and oral cancer. EIS data were collected from oral cancer (n=10), PML (n=27), and benign (n=10) lesions. EIS from lesions was compared with the EIS reading from the normal mucosa on the contralateral side of the mouth or with reference spectra from mucosal sites of control subjects (n=51). Healthy controls displayed significant differences in the EIS obtained from different oral sites. In addition, there were significant differences in the EIS of cancer and high-risk PML versus low-risk PML and controls. There was no significant difference between benign lesions and normal controls. Study subjects also deemed the EIS procedure considerably less painful and more convenient than the scalpel biopsy procedure. EIS shows promise at distinguishing among malignant, PML, and normal oral mucosa and has the potential to be developed into a clinical diagnostic tool. PMID:25285005

  12. Impact of lesion segmentation metrics on computer-aided diagnosis/detection in breast computed tomography

    PubMed Central

    Kuo, Hsien-Chi; Giger, Maryellen L.; Reiser, Ingrid; Drukker, Karen; Boone, John M.; Lindfors, Karen K.; Yang, Kai; Edwards, Alexandra

    2014-01-01

    Abstract. Evaluation of segmentation algorithms usually involves comparisons of segmentations to gold-standard delineations without regard to the ultimate medical decision-making task. We compare two segmentation evaluations methods—a Dice similarity coefficient (DSC) evaluation and a diagnostic classification task–based evaluation method using lesions from breast computed tomography. In our investigation, we use results from two previously developed lesion-segmentation algorithms [a global active contour model (GAC) and a global with local aspects active contour model]. Although similar DSC values were obtained (0.80 versus 0.77), we show that the global + local active contour (GLAC) model, as compared with the GAC model, is able to yield significantly improved classification performance in terms of area under the receivers operating characteristic (ROC) curve in the task of distinguishing malignant from benign lesions. [Area under the ROC curve (AUC)=0.78 compared to 0.63, p≪0.001]. This is mainly because the GLAC model yields better detailed information required in the calculation of morphological features. Based on our findings, we conclude that the DSC metric alone is not sufficient for evaluating segmentation lesions in computer-aided diagnosis tasks. PMID:26158052

  13. Fluorescence detection of tumors: studies on the early diagnosis of microscopic lesions in preclinical and clinical studies

    NASA Astrophysics Data System (ADS)

    Mang, Thomas S.; McGinnis, Carolyn; Crean, David H.; Khan, S.; Liebow, Charles

    1991-06-01

    The growth of microscopic tumor lesions at or beyond treatment field lesions poses major problems in the diagnosis and curative treatment of numerous cancers. Early detection techniques which clearly define the extent of condemned or field spread of disease may improve the primary treatment of the disease. In vivo fluorescence photometry is a non-imaging technique which digitally displays relative fluorescence values in volts. The sensitivity of the instrument has allowed the detection of micrometastases in both pre-clinical and clinical studies using drug doses that are 80-90 lower than those used therapeutically. This technique is now being applied in preliminary experiments to the hamster cheek pouch models to (1) discern varying grades of dysplasia; (2) levels of uptake of the drug in normal growing and quiescent tumors. Results will be shown in two models in which this technique has shown to be efficacious preclinically in the Pollard rat adenocarcinoma model in which micrometastases in the lymph node have been detected, and preliminary studies involving the hamster cheek pouch model in which the pouch is painted with 9, 10 dimethyl-1, 2-benzanthracene (DMBA) for initiation and promotion of tumors. Clinically results will be shown in which fluorescence detection, confirmed by biopsy and histopathological examination, was capable of detecting the existence of micrometastatic involvement of less than 100 cells.

  14. Detecting arsenic-related skin lesions: experiences from a large community-based survey in Bangladesh.

    PubMed

    Hore, Samar Kumar; Rahman, Mahfuzar; Yunus, Mohammad; Das, Chandra Shakhar; Yeasmin, Sultana; Ahmad, S K Akhtar; Sayed, M H Salim Ullah; Islam, Azm Maidul; Vahter, Marie; Persson, Lars Ake

    2007-04-01

    A cross-sectional survey was conducted in Matlab, Bangladesh, to determine the prevalence of skin lesions (a three-step procedure) associated with arsenic exposure and discuss validity and feasibility in relation to recommended screening algorithms. Cases with skin lesions were identified by screening above 4 years of age (n = 166,934). Trained field teams conducted a careful house-to-house screening and identified 1682 individuals with skin lesions, who were referred to physicians for confirmation. Physicians diagnosed 579 cases as probable and documented all these with digital photographs. Two experts inspected all photographs for consensus agreement that was reached for 504 cases. Using the experts' opinions as reference, the positive predictive value of the physicians' diagnosis was 87% (male = 82% vs. female = 94%; p < 0.01). The physicians had difficulties in separating arsenic-induced keratosis from differential diagnoses, while probability for correct diagnosis was high for arsenic-related pigmentation changes. Including information on current arsenic concentration in drinking water (which was masked at time of skin examination) or urine in the diagnostic algorithm should have increased the number of false negative cases. In the present transition of drinking water sources these markers of current exposure levels provide no information on past exposure. A 2-3 step procedure with house-to-house screening and clinic-based confirmation of arsenic-induced skin lesions is a feasible approach. Information on arsenic concentration in current water sources or in urine should not have improved the precision in the diagnosis. These results may have policy implications for community screening of arsenic-related skin lesions in Bangladesh and elsewhere.

  15. PET/CT detectability and classification of simulated pulmonary lesions using an SUV correction scheme

    NASA Astrophysics Data System (ADS)

    Morrow, Andrew N.; Matthews, Kenneth L., II; Bujenovic, Steven

    2008-03-01

    Positron emission tomography (PET) and computed tomography (CT) together are a powerful diagnostic tool, but imperfect image quality allows false positive and false negative diagnoses to be made by any observer despite experience and training. This work investigates PET acquisition mode, reconstruction method and a standard uptake value (SUV) correction scheme on the classification of lesions as benign or malignant in PET/CT images, in an anthropomorphic phantom. The scheme accounts for partial volume effect (PVE) and PET resolution. The observer draws a region of interest (ROI) around the lesion using the CT dataset. A simulated homogenous PET lesion of the same shape as the drawn ROI is blurred with the point spread function (PSF) of the PET scanner to estimate the PVE, providing a scaling factor to produce a corrected SUV. Computer simulations showed that the accuracy of the corrected PET values depends on variations in the CT-drawn boundary and the position of the lesion with respect to the PET image matrix, especially for smaller lesions. Correction accuracy was affected slightly by mismatch of the simulation PSF and the actual scanner PSF. The receiver operating characteristic (ROC) study resulted in several observations. Using observer drawn ROIs, scaled tumor-background ratios (TBRs) more accurately represented actual TBRs than unscaled TBRs. For the PET images, 3D OSEM outperformed 2D OSEM, 3D OSEM outperformed 3D FBP, and 2D OSEM outperformed 2D FBP. The correction scheme significantly increased sensitivity and slightly increased accuracy for all acquisition and reconstruction modes at the cost of a small decrease in specificity.

  16. Association between power law coefficients of the anatomical noise power spectrum and lesion detectability in breast imaging modalities

    NASA Astrophysics Data System (ADS)

    Chen, Lin; Abbey, Craig K.; Boone, John M.

    2013-03-01

    Previous research has demonstrated that a parameter extracted from a power function fit to the anatomical noise power spectrum, β, may be predictive of breast mass lesion detectability in x-ray based medical images of the breast. In this investigation, the value of β was compared with a number of other more widely used parameters, in order to determine the relationship between β and these other parameters. This study made use of breast CT data sets, acquired on two breast CT systems developed in our laboratory. A total of 185 breast data sets in 183 women were used, and only the unaffected breast was used (where no lesion was suspected). The anatomical noise power spectrum computed from two-dimensional region of interests (ROIs), was fit to a power function (NPS(f) = α f-β), and the exponent parameter (β) was determined using log/log linear regression. Breast density for each of the volume data sets was characterized in previous work. The breast CT data sets analyzed in this study were part of a previous study which evaluated the receiver operating characteristic (ROC) curve performance using simulated spherical lesions and a pre-whitened matched filter computer observer. This ROC information was used to compute the detectability index as well as the sensitivity at 95% specificity. The fractal dimension was computed from the same ROIs which were used for the assessment of β. The value of β was compared to breast density, detectability index, sensitivity, and fractal dimension, and the slope of these relationships was investigated to assess statistical significance from zero slope. A statistically significant non-zero slope was considered to be a positive association in this investigation. All comparisons between β and breast density, detectability index, sensitivity at 95% specificity, and fractal dimension demonstrated statistically significant association with p < 0.001 in all cases. The value of β was also found to be associated with patient age and

  17. Cardiovascular dysfunction in multiple sclerosis.

    PubMed

    Acevedo, A R; Nava, C; Arriada, N; Violante, A; Corona, T

    2000-02-01

    Cardiovascular dysfunction (CD) in multiple sclerosis (MS) is related to involvement of reflex pathways in the brainstem. The battery of CD tests was applied to a group of 40 healthy subjects and 40 patients with MS, divided in 2 subgroups according to the expanded disability status scale (EDSS). The tests included: 1) postural blood pressure changes, 2) postural heart rate changes, 3) heart rate changes on inspiration/forced expiration and 4) ECG R-R interval measurement on the Valsalva maneuver. Both groups were subjected to the functional independence scale (FIM). Imaging studies were reviewed and autonomic dysfunction at other levels was explored. The results showed a statistically significant difference (P < 0.05) in all tests when comparing patients to controls. Tests 1 and 4 had the highest significance, with findings of more severe involvement in patients with a higher EDSS and lower FIM. A correlation was also found between CD and brainstem lesions on MRI (P < 0.01). A significant number of MS patients had evidence of CD. Test 1 may be considered a simple marker, in daily clinical practice, to detect subclinical CD. Subclinical CD is a cause of disability in this group of patients.

  18. The Diagnostic Value of Superb Microvascular Imaging (SMI) in Detecting Blood Flow Signals of Breast Lesions: A Preliminary Study Comparing SMI to Color Doppler Flow Imaging.

    PubMed

    Ma, Yan; Li, Gang; Li, Jing; Ren, Wei-dong

    2015-09-01

    The correlation between color Doppler flow imaging (CDFI) and Superb Microvascular Imaging (SMI) for detecting blood flow in breast lesions was investigated, as was the diagnostic value of SMI in differentiating benign from malignant breast lesions.These lesions were evaluated using both CDFI and SMI according to Adler's method. Pathologic examination showed 57 malignant lesions and 66 benign lesions. The number of blood vessels in a single mass was detected by 2 techniques (SMI and CDFI), and the difference between the 2 values (SMI-CDFI) was calculated. The optimal threshold for the diagnosis of malignant neoplasms and the diagnostic performances of SMI, CDFI, and SMI-CDFI were calculated.For the total lesions and malignant lesions alone, the difference between SMI and CDFI for detecting blood flow was significant (P < 0.01), but the difference was not significant for benign lesions (P = 0.15). The area under the receiver operating characteristic curve was 0.73 (95% confidence interval [CI]: 0.64-0.82) for CDFI; 0.81 (95% CI: 0.74-0.89) for SMI; and 0.89 (95% CI: 0.82-0.95) for SMI-CDFI. Furthermore, the modality of "SMI-CDFI" showed the best diagnostic performance.SMI provides further microvessel information in breast lesions. The diagnostic modality of "SMI-CDFI" can improve the diagnostic performance of ultrasound in the differentiation between benign and malignant masses.

  19. Vaginal micropapillary lesions are not related to human papillomavirus infection: in situ hybridization and polymerase chain reaction detection techniques.

    PubMed

    Garzetti, G G; Ciavattini, A; Goteri, G; Menzo, S; De Nictolis, M; Clementi, M; Brugia, M; Romanini, C

    1994-01-01

    The objective of this study was to assess the human papillomavirus DNA presence in vaginal papillary lesions, with particular regard to micropapillomatosis to better define their clinical significance. Prospective study: the study population was composed of 62 women who were recruited consecutively from the Colposcopy Centre of the Ancona University, Department of Obstetrics and Gynecology, on the grounds of vaginal papillomatosis or/and typical acuminata warts. Biopsies for routine histology, and for human papillomavirus (HPV) DNA detection by means of in situ hybridization and polymerase chain reaction (PCR) were taken from the papillary lesions and from 24 healthy women, who were selected as controls. Macroscopically, vaginal micropapillomatosis was ascertained in 51 cases (82.3%), while in 11 cases (17.7%) the colposcopic diagnosis was condyloma acuminatum. During in situ hybridization, HPV DNA positivity was observed in 8 (9.4%) out of 85 samples of squamous papillae and in 11 (64.7%) out of 17 samples of condylomata; in control specimens, HPV DNA was detected in 2 (8.3%) out of 24 bioptic samples. The correspondence between in situ hybridization and PCR was 96.1%, with 17.4% more diagnosis obtained by PCR. Vaginal micropapillomatosis may be regarded as a variation in the normal anatomy of the lower genital tract without any significant relationship with HPV infection, and as a lesion easily distinguishable from condylomata acuminata by clinical examination alone. PMID:7959342

  20. [Systemic sclerosis].

    PubMed

    Schinke, Susanne; Riemekasten, Gabriela

    2016-04-01

    Systemic sclerosis is a challenging and heterogeneous disease due to the involvement of multiple organs and the high impact on morbidity and quality of life. Lung fibrosis, pulmonary arterial hypertension, and cardiac manifestations are main causes of systemic sclerosis-related deaths. In addition, patients suffer from a various range of co-morbidities such as malnutrition, depression, osteoporosis, malignancies, which are increased in these patients and have to be identified and treated. Early assessment of organ damage is a key to therapeutic success. The discovery of pathogenic autoantibodies combined with increased evidence of effective immunosuppressive and vasoactive treatment strategies are major developments in the therapy of the disease. At present, several clinical studies are ongoing and some of the biological therapies are promising.

  1. GPCALMA: implementation in Italian hospitals of a computer aided detection system for breast lesions by mammography examination.

    PubMed

    Lauria, Adele

    2009-06-01

    We describe the implementation in several Italian hospitals of a computer aided detection (CAD) system, named GPCALMA (grid platform for a computer aided library in mammography), for the automatic search of lesions in X-ray mammographies. GPCALMA has been under development since 1999 by a community of physicists of the Italian National Institute for Nuclear Physics (INFN) in collaboration with radiologists. This CAD system was tested as a support to radiologists in reading mammographies. The main system components are: (i) the algorithms implemented for the analysis of digitized mammograms to recognize suspicious lesions, (ii) the database of digitized mammographic images, and (iii) the PC-based digitization and analysis workstation and its user interface. The distributed nature of data and resources and the prevalence of geographically remote users suggested the development of the system as a grid application: the design of this networked version is also reported. The paper describes the system architecture, the database of digitized mammographies, the clinical workstation and the medical applications carried out to characterize the system. A commercial CAD was evaluated in a comparison with GPCALMA by analysing the medical reports obtained with and without the two different CADs on the same dataset of images: with both CAD a statistically significant increase in sensitivity was obtained. The sensitivity in the detection of lesions obtained for microcalcification and masses was 96% and 80%, respectively. An analysis in terms of receiver operating characteristic (ROC) curve was performed for massive lesion searches, achieving an area under the ROC curve of A(z)=0.783+/-0.008. Results show that the GPCALMA CAD is ready to be used in the radiological practice, both for screening mammography and clinical studies. GPCALMA is a starting point for the development of other medical imaging applications such as the CAD for the search of pulmonary nodules, currently under

  2. The radial diffusivity and magnetization transfer pool size ratio are sensitive markers for demyelination in a rat model of type III multiple sclerosis (MS) lesions

    PubMed Central

    Janve, Vaibhav A.; Zu, Zhongliang; Yao, Song-Yi; Li, Ke; Zhang, Fang Lin; Wilson, Kevin; Ou, Xiawei; Does, Mark D.; Subramaniam, Sriram; Gochberg, Daniel F.

    2013-01-01

    Determining biophysical sensitivity and specificity of quantitative magnetic resonance imaging is essential to develop effective imaging metrics of neurodegeneration. Among these metrics apparent pool size ratio (PSR) from quantitative magnetization transfer (qMT) imaging and radial diffusivity (RD) from diffusion tensor imaging (DTI) are both known to relate to histological measure of myelin density and integrity. However their relative sensitivities towards quantitative myelin detection are unknown. In this study, we correlated high-resolution quantitative magnetic resonance imaging measures of subvoxel tissue structures with corresponding quantitative myelin histology in a lipopolysacharide (LPS) mediated animal model of MS. Specifically, we acquired quantitative magnetization transfer (qMT) and diffusion tensor imaging (DTI) metrics (on the same tissue sample) in an animal model system of type III oligodendrogliopathy which lacked prominent lymphocytic infiltration, a system that had not been previously examined with quantitative MRI. We find that the qMT measured apparent pool size ratio (PSR) showed the strongest correlation with a histological measure of myelin content. DTI measured RD showed the next strongest correlation, and other DTI and relaxation parameters (such as the longitudinal relaxation rate (R1f) or fractional anisotropy (FA)) showed considerably weaker correlations with myelin content. PMID:23481461

  3. Automated metastatic brain lesion detection: a computer aided diagnostic and clinical research tool

    NASA Astrophysics Data System (ADS)

    Devine, Jeremy; Sahgal, Arjun; Karam, Irene; Martel, Anne L.

    2016-03-01

    The accurate localization of brain metastases in magnetic resonance (MR) images is crucial for patients undergoing stereotactic radiosurgery (SRS) to ensure that all neoplastic foci are targeted. Computer automated tumor localization and analysis can improve both of these tasks by eliminating inter and intra-observer variations during the MR image reading process. Lesion localization is accomplished using adaptive thresholding to extract enhancing objects. Each enhancing object is represented as a vector of features which includes information on object size, symmetry, position, shape, and context. These vectors are then used to train a random forest classifier. We trained and tested the image analysis pipeline on 3D axial contrast-enhanced MR images with the intention of localizing the brain metastases. In our cross validation study and at the most effective algorithm operating point, we were able to identify 90% of the lesions at a precision rate of 60%.

  4. Glomus Tumors: A Review of Preoperative Magnetic Resonance Imaging to Detect Satellite Lesions.

    PubMed

    Giugale, Juan M; Fowler, John R

    2015-10-01

    Glomus tumors are malformations of the neuromyoarterial system that commonly develop in the digits and cause exquisite tenderness, especially with cold temperatures. Treatment typically involves surgical excision, although there is a tendency to avoid aggressive resections, which may lead to aesthetically displeasing nail plate deformities. In a minority of patients, symptoms may persist and the tumor may recur. The etiology of the persistent of symptoms is debatable. One theory for the persistence of symptoms is an incomplete initial excision of the glomus tumor. Another theory suggests that clinically unapparent satellite lesions exist at the time of diagnosis that are not excised, and they later mature into symptomatic recurrent tumors. Although not clinically visible, if present, these satellite lesions should be seen on preoperative magnetic resonance imaging. The authors reviewed all cases of pathology-confirmed glomus tumors in the past 7 years at a single institution in which preoperative magnetic resonance imaging using a high-powered 3.0 Tesla (General Electric, Buckinghamshire, United Kingdom) magnet was performed. Six cases met inclusion criteria and only 1 case developed a recurrent glomus tumor. None of the cases were found to have satellite lesions associated with the primary glomus tumor on magnetic resonance imaging. Preventing recurrence seems to be dependent on the completeness of the initial excision. Preoperative magnetic resonance imaging is a valuable tool used to delineate the extent of the tumor for surgical planning. PMID:26488783

  5. Gray matter damage in multiple sclerosis: Impact on clinical symptoms.

    PubMed

    van Munster, Caspar E P; Jonkman, Laura E; Weinstein, Henry C; Uitdehaag, Bernard M J; Geurts, Jeroen J G

    2015-09-10

    Traditionally, multiple sclerosis (MS) is considered to be a disease primarily affecting the white matter (WM). However, the development of some clinical symptoms such as cognitive impairment cannot be fully explained by the severity of WM pathology alone. During the past decades it became clear that gray matter (GM) damage of the brain is also of major importance in patients with MS. Thanks to improved magnetic resonance imaging techniques, the in vivo detection of GM pathology became possible, enabling a better understanding of the manifestation of various clinical symptoms, such as cognitive impairment. Using higher field strengths and specific sequences, detection of cortical lesions was increased. However, despite these improvements, visualization of cortical MS lesions remains difficult (only about 30-50% of histopathologically confirmed lesions can be detected at 7 Tesla magnetic resonance imaging (MRI)). Furthermore, more research is needed to understand the exact interplay of cortical lesions, GM atrophy and WM pathology in the development of clinical symptoms. In this review, we summarize the historical background that preceded current research and provide an overview of the current knowledge on clinical consequences of GM pathology in MS in terms of disability, cognitive impairment and other clinically important signs such as epileptic seizures. PMID:26164500

  6. Comparison of Color Fundus Photography, Infrared Fundus Photography, and Optical Coherence Tomography in Detecting Retinal Hamartoma in Patients with Tuberous Sclerosis Complex

    PubMed Central

    Bai, Da-Yong; Wang, Xu; Zhao, Jun-Yang; Li, Li; Gao, Jun; Wang, Ning-Li

    2016-01-01

    Background: A sensitive method is required to detect retinal hamartomas in patients with tuberous sclerosis complex (TSC). The aim of the present study was to compare the color fundus photography, infrared imaging (IFG), and optical coherence tomography (OCT) in the detection rate of retinal hamartoma in patients with TSC. Methods: This study included 11 patients (22 eyes) with TSC, who underwent color fundus photography, IFG, and spectral-domain OCT to detect retinal hamartomas. TSC1 and TSC2 mutations were tested in eight patients. Results: The mean age of the 11 patients was 8.0 ± 2.1 years. The mean spherical equivalent was −0.55 ± 1.42 D by autorefraction with cycloplegia. In 11 patients (22 eyes), OCT, infrared fundus photography, and color fundus photography revealed 26, 18, and 9 hamartomas, respectively. The predominant hamartoma was type I (55.6%). All the hamartomas that detected by color fundus photography or IFG can be detected by OCT. Conclusion: Among the methods of color fundus photography, IFG, and OCT, the OCT has higher detection rate for retinal hamartoma in TSC patients; therefore, OCT might be promising for the clinical diagnosis of TSC. PMID:27174333

  7. New Lesions Detected by Single Nucleotide Polymorphism Array–Based Chromosomal Analysis Have Important Clinical Impact in Acute Myeloid Leukemia

    PubMed Central

    Tiu, Ramon V.; Gondek, Lukasz P.; O'Keefe, Christine L.; Huh, Jungwon; Sekeres, Mikkael A.; Elson, Paul; McDevitt, Michael A.; Wang, Xiao Fei; Levis, Mark J.; Karp, Judith E.; Advani, Anjali S.; Maciejewski, Jaroslaw P.

    2009-01-01

    Purpose Cytogenetics is the primary outcome predictor in acute myeloid leukemia (AML). Metaphase cytogenetics (MC) detects an abnormal karyotype in only half of patients with AML, however. Single nucleotide polymorphism arrays (SNP-A) can detect acquired somatic uniparental disomy (UPD) and other cryptic defects, even in samples deemed normal by MC. We hypothesized that SNP-A will improve detection of chromosomal defects in AML and that this would enhance the prognostic value of MC. Patients and Methods We performed 250K and 6.0 SNP-A analyses on 140 patients with primary (p) and secondary (s) AML and correlated the results with clinical outcomes and Flt-3/nucleophosmin (NPM-1) status. Results SNP-A is more sensitive than MC in detecting unbalanced lesions (pAML, 65% v 39%, P = .002; and sAML, 78% v 51%, P = .003). Acquired somatic UPD, not detectable by MC, was common in our AML cohort (29% in pAML and 35% in sAML). Patients with SNP-A lesions including acquired somatic UPD exhibited worse overall survival (OS) and event-free survival (EFS) in pAML with normal MC and in pAML/sAML with abnormal MC. SNP-A improved the predictive value of Flt-3 internal tandem duplication/NPM-1 status, with inferior survival seen in patients with additional SNP-A defects. Multivariate analyses confirmed the independent predictive value of SNP-A defects for OS (hazard ratio [HR] = 2.52; 95% CI, 1.29 to 5.22; P = .006) and EFS (HR = 1.72; 95% CI, 1.12 to 3.48; P = .04). Conclusion SNP-A analysis allows enhanced detection of chromosomal abnormalities and provides important prognostic impact in AML. PMID:19770377

  8. Nodal, paranodal and juxtaparanodal axonal proteins during demyelination and remyelination in multiple sclerosis.

    PubMed

    Coman, I; Aigrot, M S; Seilhean, D; Reynolds, R; Girault, J A; Zalc, B; Lubetzki, C

    2006-12-01

    Saltatory conduction in myelinated fibres depends on the specific molecular organization of highly specialized axonal domains at the node of Ranvier, the paranodal and the juxtaparanodal regions. Voltage-gated sodium channels (Na(v)) have been shown to be deployed along the naked demyelinated axon in experimental models of CNS demyelination and in multiple sclerosis lesions. Little is known about aggregation of nodal, paranodal and juxtaparanodal constituents during the repair process. We analysed by immunohistochemistry on free-floating sections from multiple sclerosis brains the expression and distribution of nodal (Na(v) channels), paranodal (paranodin/Caspr) and juxtaparanodal (K(v) channels and Caspr2) molecules in demyelinated and remyelinated lesions. Whereas in demyelinated lesions, paranodal and juxtaparanodal proteins are diffusely distributed on denuded axons, the distribution of Na(v) channels is heterogeneous, with a diffuse immunoreactivity but also few broad Na(v) channel aggregates in all demyelinated lesions. In contrast to the demyelinated plaques, all remyelinated lesions are characterized by the detection of aggregates of Na(v) channels, paranodin/Caspr, K(v) channels and Caspr2. Our data suggest that these aggregates precede remyelination, and that Na(v) channel aggregation is the initial event, followed by aggregation of paranodal and then juxtaparanodal axonal proteins. Remyelination takes place in multiple sclerosis tissue but myelin repair is often incomplete, and the reasons for this remyelination deficit are many. We suggest that a defect of Na(v) channel aggregation might be involved in the remyelination failure in demyelinated lesions with spared axons and oligodendroglial cells. PMID:16766541

  9. Detection of high-risk atherosclerotic lesions by time-resolved fluorescence spectroscopy based on the Laguerre deconvolution technique

    NASA Astrophysics Data System (ADS)

    Jo, J. A.; Fang, Q.; Papaioannou, T.; Qiao, J. H.; Fishbein, M. C.; Beseth, B.; Dorafshar, A. H.; Reil, T.; Baker, D.; Freischlag, J.; Marcu, L.

    2006-02-01

    This study introduces new methods of time-resolved laser-induced fluorescence spectroscopy (TR-LIFS) data analysis for tissue characterization. These analytical methods were applied for the detection of atherosclerotic vulnerable plaques. Upon pulsed nitrogen laser (337 nm, 1 ns) excitation, TR-LIFS measurements were obtained from carotid atherosclerotic plaque specimens (57 endarteroctomy patients) at 492 distinct areas. The emission was both spectrally- (360-600 nm range at 5 nm interval) and temporally- (0.3 ns resolution) resolved using a prototype clinically compatible fiber-optic catheter TR-LIFS apparatus. The TR-LIFS measurements were subsequently analyzed using a standard multiexponential deconvolution and a recently introduced Laguerre deconvolution technique. Based on their histopathology, the lesions were classified as early (thin intima), fibrotic (collagen-rich intima), and high-risk (thin cap over necrotic core and/or inflamed intima). Stepwise linear discriminant analysis (SLDA) was applied for lesion classification. Normalized spectral intensity values and Laguerre expansion coefficients (LEC) at discrete emission wavelengths (390, 450, 500 and 550 nm) were used as features for classification. The Laguerre based SLDA classifier provided discrimination of high-risk lesions with high sensitivity (SE>81%) and specificity (SP>95%). Based on these findings, we believe that TR-LIFS information derived from the Laguerre expansion coefficients can provide a valuable additional dimension for the diagnosis of high-risk vulnerable atherosclerotic plaques.

  10. Reversible hippocampal lesions detected on magnetic resonance imaging in two cases of transient selective amnesia for simple machine operation.

    PubMed

    Yamaoka, Yumiko; Bandoh, Mitsuaki; Kawai, Kensuke

    2016-08-01

    We report two extremely rare cases involving the development of transient selective retrograde amnesia for simple machine operation lasting for several hours. A 61-year-old male taxi driver suddenly became unable to operate a taximeter, and a 66-year-old female janitor suddenly became unable to use a fax machine. They could precisely recount their episodes to others both during and after the attacks, and their memories during their attacks corresponded to the memory of the witness and the medical records of the doctor, respectively. Therefore, it appears that these individuals remained alert and did not develop anterograde amnesia during their attacks. On day 4, they underwent high-resolution magnetic resonance imaging (MRI), and diffusion-weighted MRI with 2-mm section thickness revealed small high-intensity signal lesions in the left hippocampal cornu ammonis area 1 (CA1) region. However, these lesions disappeared during the chronic phase. This is the first report describing lesions detected by MRI in patients with transient selective amnesia without anterograde amnesia. Reversible damage to the hippocampal CA1 region may cause transient selective amnesia by impairing the retrieval of relevant memories. PMID:27367337

  11. Reversible hippocampal lesions detected on magnetic resonance imaging in two cases of transient selective amnesia for simple machine operation.

    PubMed

    Yamaoka, Yumiko; Bandoh, Mitsuaki; Kawai, Kensuke

    2016-08-01

    We report two extremely rare cases involving the development of transient selective retrograde amnesia for simple machine operation lasting for several hours. A 61-year-old male taxi driver suddenly became unable to operate a taximeter, and a 66-year-old female janitor suddenly became unable to use a fax machine. They could precisely recount their episodes to others both during and after the attacks, and their memories during their attacks corresponded to the memory of the witness and the medical records of the doctor, respectively. Therefore, it appears that these individuals remained alert and did not develop anterograde amnesia during their attacks. On day 4, they underwent high-resolution magnetic resonance imaging (MRI), and diffusion-weighted MRI with 2-mm section thickness revealed small high-intensity signal lesions in the left hippocampal cornu ammonis area 1 (CA1) region. However, these lesions disappeared during the chronic phase. This is the first report describing lesions detected by MRI in patients with transient selective amnesia without anterograde amnesia. Reversible damage to the hippocampal CA1 region may cause transient selective amnesia by impairing the retrieval of relevant memories.

  12. Identification of error making patterns in lesion detection on digital breast tomosynthesis using computer-extracted image features

    NASA Astrophysics Data System (ADS)

    Wang, Mengyu; Zhang, Jing; Grimm, Lars J.; Ghate, Sujata V.; Walsh, Ruth; Johnson, Karen S.; Lo, Joseph Y.; Mazurowski, Maciej A.

    2016-03-01

    Digital breast tomosynthesis (DBT) can improve lesion visibility by eliminating the issue of overlapping breast tissue present in mammography. However, this new modality likely requires new approaches to training. The issue of training in DBT is not well explored. We propose a computer-aided educational approach for DBT training. Our hypothesis is that the trainees' educational outcomes will improve if they are presented with cases individually selected to address their weaknesses. In this study, we focus on the question of how to select such cases. Specifically, we propose an algorithm that based on previously acquired reading data predicts which lesions will be missed by the trainee for future cases (i.e., we focus on false negative error). A logistic regression classifier was used to predict the likelihood of trainee error and computer-extracted features were used as the predictors. Reader data from 3 expert breast imagers was used to establish the ground truth and reader data from 5 radiology trainees was used to evaluate the algorithm performance with repeated holdout cross validation. Receiver operating characteristic (ROC) analysis was applied to measure the performance of the proposed individual trainee models. The preliminary experimental results for 5 trainees showed the individual trainee models were able to distinguish the lesions that would be detected from those that would be missed with the average area under the ROC curve of 0.639 (95% CI, 0.580-0.698). The proposed algorithm can be used to identify difficult cases for individual trainees.

  13. Use of functional mass in renal scintigraphy to detect segmental arterial lesions

    SciTech Connect

    Stibolt, T.B. Jr.; Bacher, J.D.; Dunnick, N.R.; Lock, A.; Jones, A.E.; Bailey, J.J.

    1982-04-01

    Renography using a gamma camera, a minicomputer, (/sup 123/I)orthoiodohippurate ((/sup 123/I)OIH), and a canine model was employed to evaluate computer-generated maps of regional renal function. Renograms were obtained before and after ligations of the right renal arterial branch in four dogs, with subsequent angiographic and histologic confirmation of the lesions. Postoperative time-activity curves were normal. Washout and persistence index in three of four right kidneys showed regional abnormality. Functional renal mapping may provide a clinical technique for evaluating human renal vascular hypertension.

  14. [Non-small bowel lesions detected with capsule endoscopy in patients with obscure gastrointestinal bleeding].

    PubMed

    Juanmartiñena Fernández, J F; Fernández-Urién, I; Saldaña Dueñas, C; Elosua González, A; Borda Martín, A; Vila Costas, J J

    Obscure gastrointestinal bleeding accounts for approximately 5-10% of patients presenting with gastrointestinal haemorrhage. The majority of lesions responsible were found to be located in the small bowel. Currently, capsule en-doscopy is the first-line tool to investigate the small bowel as it is a non-invasive, feasible and simple procedure. Howe-ver, capsule endoscopy sometimes identifies the source of bleeding outside the small bowel and within the reach of conventional endoscopy. We present the case of a 46 year-old man with few prior negative endoscopic procedures and iron-deficiency anaemia due to gastric GIST. PMID:27599960

  15. Short-term MRI measurements as predictors of EDSS progression in relapsing-remitting multiple sclerosis: grey matter atrophy but not lesions are predictive in a real-life setting

    PubMed Central

    Young, Kim; Schippling, Sven; Martin, Roland; Heesen, Christoph; Siemonsen, Susanne

    2016-01-01

    Background Magnetic resonance imaging (MRI) is the best biomarker of inflammatory disease activity in relapsing remitting Multiple Sclerosis (RRMS) so far but the association with disability is weak. Appearance of new MRI-lesions is used to evaluate response to immunotherapies in individual patients as well as being the most common primary outcome in phase-2 trials. Measurements of brain atrophy show promising outcomes in natural cohort studies and some phase-2 trials. From a theoretical perspective they might represent irreversible neurodegeneration and be more closely associated with disability. However, these atrophy measurements are not yet established as prognostic factors in real-life clinical routine. High field MRI has improved image quality and resolution and new methods to measure atrophy dynamics have become available. Objective To investigate the predictive value of MRI classification criteria in to high/low atrophy and inflammation groups, and to explore predictive capacity of two consecutive routine MRI scans for disability progression in RRMS in a real-life prospective cohort. Methods 82 RRMS-patients (40 untreated, 42 treated with immunotherapies, mean age 40 years, median Expanded Disability Status Scale (EDSS) of 2, underwent two clinically indicated MRI scans (3 Tesla) within 5–14 months, and EDSS assessment after a mean of 3.0 (1.5–4.2) years. We investigated the predictive value of predefined classifications in low/high inflammatory and atrophy groups for EDSS progression (≥1.5 if baseline EDSS = 0, ≥1.0 if baseline EDSS <5, ≥0.5 for other) by chi-square tests and by analysis of variance (ANOVA). The classifications were based on current scientific or clinical recommendation (e.g., treatment response criteria). Brain atrophy was assessed with three different methods (SIENA, SIENAX, and FreeSurfer). Post-hoc analyses aimed to explore clinical data and dynamics of MRI outcomes as predictors in multivariate linear and logit models

  16. Short-term MRI measurements as predictors of EDSS progression in relapsing-remitting multiple sclerosis: grey matter atrophy but not lesions are predictive in a real-life setting

    PubMed Central

    Young, Kim; Schippling, Sven; Martin, Roland; Heesen, Christoph; Siemonsen, Susanne

    2016-01-01

    Background Magnetic resonance imaging (MRI) is the best biomarker of inflammatory disease activity in relapsing remitting Multiple Sclerosis (RRMS) so far but the association with disability is weak. Appearance of new MRI-lesions is used to evaluate response to immunotherapies in individual patients as well as being the most common primary outcome in phase-2 trials. Measurements of brain atrophy show promising outcomes in natural cohort studies and some phase-2 trials. From a theoretical perspective they might represent irreversible neurodegeneration and be more closely associated with disability. However, these atrophy measurements are not yet established as prognostic factors in real-life clinical routine. High field MRI has improved image quality and resolution and new methods to measure atrophy dynamics have become available. Objective To investigate the predictive value of MRI classification criteria in to high/low atrophy and inflammation groups, and to explore predictive capacity of two consecutive routine MRI scans for disability progression in RRMS in a real-life prospective cohort. Methods 82 RRMS-patients (40 untreated, 42 treated with immunotherapies, mean age 40 years, median Expanded Disability Status Scale (EDSS) of 2, underwent two clinically indicated MRI scans (3 Tesla) within 5–14 months, and EDSS assessment after a mean of 3.0 (1.5–4.2) years. We investigated the predictive value of predefined classifications in low/high inflammatory and atrophy groups for EDSS progression (≥1.5 if baseline EDSS = 0, ≥1.0 if baseline EDSS <5, ≥0.5 for other) by chi-square tests and by analysis of variance (ANOVA). The classifications were based on current scientific or clinical recommendation (e.g., treatment response criteria). Brain atrophy was assessed with three different methods (SIENA, SIENAX, and FreeSurfer). Post-hoc analyses aimed to explore clinical data and dynamics of MRI outcomes as predictors in multivariate linear and logit models

  17. Detection of Carious Lesions and Restorations Using Particle Swarm Optimization Algorithm

    PubMed Central

    Naebi, Mohammad; Saberi, Eshaghali; Risbaf Fakour, Sirous; Naebi, Ahmad; Hosseini Tabatabaei, Somayeh; Ansari Moghadam, Somayeh; Bozorgmehr, Elham; Davtalab Behnam, Nasim; Azimi, Hamidreza

    2016-01-01

    Background/Purpose. In terms of the detection of tooth diagnosis, no intelligent detection has been done up till now. Dentists just look at images and then they can detect the diagnosis position in tooth based on their experiences. Using new technologies, scientists will implement detection and repair of tooth diagnosis intelligently. In this paper, we have introduced one intelligent method for detection using particle swarm optimization (PSO) and our mathematical formulation. This method was applied to 2D special images. Using developing of our method, we can detect tooth diagnosis for all of 2D and 3D images. Materials and Methods. In recent years, it is possible to implement intelligent processing of images by high efficiency optimization algorithms in many applications especially for detection of dental caries and restoration without human intervention. In the present work, we explain PSO algorithm with our detection formula for detection of dental caries and restoration. Also image processing helped us to implement our method. And to do so, pictures taken by digital radiography systems of tooth are used. Results and Conclusion. We implement some mathematics formula for fitness of PSO. Our results show that this method can detect dental caries and restoration in digital radiography pictures with the good convergence. In fact, the error rate of this method was 8%, so that it can be implemented for detection of dental caries and restoration. Using some parameters, it is possible that the error rate can be even reduced below 0.5%. PMID:27212947

  18. Detection of Carious Lesions and Restorations Using Particle Swarm Optimization Algorithm.

    PubMed

    Naebi, Mohammad; Saberi, Eshaghali; Risbaf Fakour, Sirous; Naebi, Ahmad; Hosseini Tabatabaei, Somayeh; Ansari Moghadam, Somayeh; Bozorgmehr, Elham; Davtalab Behnam, Nasim; Azimi, Hamidreza

    2016-01-01

    Background/Purpose. In terms of the detection of tooth diagnosis, no intelligent detection has been done up till now. Dentists just look at images and then they can detect the diagnosis position in tooth based on their experiences. Using new technologies, scientists will implement detection and repair of tooth diagnosis intelligently. In this paper, we have introduced one intelligent method for detection using particle swarm optimization (PSO) and our mathematical formulation. This method was applied to 2D special images. Using developing of our method, we can detect tooth diagnosis for all of 2D and 3D images. Materials and Methods. In recent years, it is possible to implement intelligent processing of images by high efficiency optimization algorithms in many applications especially for detection of dental caries and restoration without human intervention. In the present work, we explain PSO algorithm with our detection formula for detection of dental caries and restoration. Also image processing helped us to implement our method. And to do so, pictures taken by digital radiography systems of tooth are used. Results and Conclusion. We implement some mathematics formula for fitness of PSO. Our results show that this method can detect dental caries and restoration in digital radiography pictures with the good convergence. In fact, the error rate of this method was 8%, so that it can be implemented for detection of dental caries and restoration. Using some parameters, it is possible that the error rate can be even reduced below 0.5%. PMID:27212947

  19. Multiple Sclerosis

    PubMed Central

    2013-01-01

    Multiple sclerosis (MS) is a chronic progressive demyelinating disease of the central nervous system. Common manifestations include paresthesias, diplopia, loss of vision, numbness or weakness of the limbs, bowel or bladder dysfunction, spasticity, ataxia, fatigue, and mental changes. Four main patterns of MS are recognized: relapsing remitting, primary progressive, secondary progressive, and progressive relapsing. The cause of MS is unknown, although it appears to be an autoimmune disease. Much of what is known about MS has been learned from an animal model of the disease, experimental allergic encephalomyelitis. PMID:24381825

  20. Multiple Sclerosis.

    PubMed

    Schiess, Nicoline; Calabresi, Peter A

    2016-08-01

    It is estimated that there are 300,000 people with multiple sclerosis (MS) in the United States and 2.3 million worldwide. Each MS attack can affect function in cognitive, emotional, motoric, sensory, or visual domains. Patients are often struck in the prime of their lives as they attempt to move forward with career, and family. Since the previous 2010 Seminars in Neurology Pearls and Pitfalls issue, the world of MS has drastically changed and advanced. Here the authors address the ever-changing MS world in both treatment options and diagnostics, covering easily missed differential diagnoses, newly available immunomodulatory therapy, and the challenges of safely treating patients. PMID:27643903

  1. Fast Whole-Brain Three-dimensional Macromolecular Proton Fraction Mapping in Multiple Sclerosis

    PubMed Central

    Bowen, James D.; Samsonov, Alexey; Repovic, Pavle; Mayadev, Angeli; Qian, Peiqing; Gangadharan, Beena; Keogh, Bart P.; Maravilla, Kenneth R.; Jung Henson, Lily K.

    2015-01-01

    (r = −0.74 and 0.81; P < .001) followed by WMwhite matter (r = −0.57 and 0.72; P < .01) and lesions (r = −0.42 and 0.50; P < .05). R1 and MTmagnetization transfer ratio in all tissues were significantly less correlated with clinical scores than GMgray matter MPFmacromolecular proton fraction (P < .05). Conclusion MPFmacromolecular proton fraction mapping enables quantitative assessment of demyelination in normal-appearing brain tissues and shows primary clinical relevance of GMgray matter damage in MSmultiple sclerosis. MPFmacromolecular proton fraction outperforms MTmagnetization transfer ratio and R1 in detection of MSmultiple sclerosis-related tissue changes. © RSNA, 2014 PMID:25208343

  2. A Study of the Potential to Detect Caries Lesions at the White-Spot Stage Using V(Z) Technique

    NASA Astrophysics Data System (ADS)

    Bakulin, E. Y.; Denisova, L. A.; Maev, R. Gr.

    Current wide-spread methods of non-destructive methods of caries diagnostics, such as X-ray techniques, do not provide the possibility to efficiently detect enamel caries lesions at the beginning ("white-spot") stage, when the tooth tissue is only slightly altered and no loss of the tissue occurs. Therefore, it is of paramount importance to develop new, more sensitive methods of caries diagnostics. In this paper, certain aspects of the ultrasonic approach to the problem are discussed - in particular, detection of the enamel's surface caries at the white-spot stage with a focused ultrasonic sensor positioned in front of the caries lesion (without cross-sectioning the tooth). Theoretical model using V(z) approach for layered media was applied to perform computer simulations resulting in V(z) curves for the different parameters of carious tissue and the degree of degradation. The curves were analyzed and it was shown that, comparing to a short-pulse/echo technique, V(z) approach provides much better distinction between sound and carious enamel and even makes possible to evaluate the degree of demineralization.

  3. Detection of Intranasally Delivered Bone Marrow-Derived Mesenchymal Stromal Cells in the Lesioned Mouse Brain: A Cautionary Report

    PubMed Central

    Chartoff, Elena H.; Damez-Werno, Diane; Sonntag, Kai C.; Hassinger, Linda; Kaufmann, Daniel E.; Peterson, Jesse; McPhie, Donna; Cataldo, Anne M.; Cohen, Bruce M.

    2011-01-01

    Bone marrow-derived mesenchymal stromal cells (MSCs) hold promise for autologous treatment of neuropathologies. Intranasal delivery is relatively noninvasive and has recently been reported to result in transport of MSCs to the brain. However, the ability of MSCs to migrate from nasal passages to sites of neuropathology and ultimately survive has not been fully examined. In this paper, we harvested MSCs from transgenic mice expressing enhanced green fluorescent protein (cells hereafter referred to as MSC-EGFP) and delivered them intranasally to wild-type mice sustaining mechanical lesions in the striatum. Using fluorescent, colorimetric, and ultrastructural detection methods, GFP-expressing cells were undetectable in the brain from 3 hours to 2 months after MSC delivery. However, bright autofluorescence that strongly resembled emission from GFP was observed in the olfactory bulb and striatum of lesioned control and MSC-EGFP-treated mice. In a control experiment, we directly implanted MSC-EGFPs into the mouse striatum and detected robust GFP expression 1 and 7 days after implantation. These findings suggest that—under our conditions—intranasally delivered MSC-EGFPs do not survive or migrate in the brain. Furthermore, our observations highlight the necessity of including appropriate controls when working with GFP as a cellular marker. PMID:22190964

  4. Clinical and molecular insights into tuberous sclerosis complex renal disease.

    PubMed

    Siroky, Brian J; Yin, Hong; Bissler, John J

    2011-06-01

    Patients with tuberous sclerosis complex are at great risk of developing renal lesions as part of their disease. These lesions include renal cysts and tumors. Significant advances in understanding the cell biology of these renal lesions has already led to clinical trials demonstrating that pharmacological interventions are likely possible. This review focuses on the pathology of these renal lesions, their underlying cell biology, and the possible therapeutic strategies that may prove to significantly improve care for these patients.

  5. Biomonitoring of primary aluminium industry workers: detection of micronuclei and repairable DNA lesions by alkaline SCGE.

    PubMed

    Crebelli, Riccardo; Carta, Plinio; Andreoli, Cristina; Aru, Gabriella; Dobrowolny, Gabriella; Rossi, Sabrina; Zijno, Andrea

    2002-04-26

    The genetic effects of occupational exposure to low polycyclic aromatic hydrocarbon (PAH) concentrations were investigated in primary aluminium industry workers. The study subjects were employed in a plant that uses pre-baked anode cells, and has relatively low PAH contamination. Forty-two male workers belonging to different job categories (anode fabrication, baking, rodding, electrolysis, maintenance), together with 16 male local residents with no occupational exposure to PAHs were selected for the analysis of micronuclei and DNA lesions in peripheral lymphocytes. The incidence of micronuclei determined in 1000 cytokinesis-blocked cells in each subject was not significantly different between workers and controls (8.5+/-5.4 per thousand versus 9.7+/-4.9 per thousand, respectively), nor between smokers and non-smokers (8.3+/-5.8 per thousand versus 9.2+/-5.1 per thousand), but was significantly (P<0.05) related to the subjects' age. Also the analysis of DNA damage in unstimulated and mitogen-stimulated lymphocytes by single cell gel electrophoresis (SCGE) did not show significant differences between the studied groups (average tail moment values were 0.53+/-0.53 and 0.49+/-0.45 microm in exposed subjects and controls, respectively). However, when lymphocytes were cultured in the presence of cytosine arabinoside (Ara-C, 1 microg/ml for 16h) the SCGE analysis revealed a significant (P=0.018) difference in tail moment values between aluminium workers and controls (1.73+/-1.05 microm versus 0.93+/-0.88 microm, respectively). This difference may highlight an excess of relatively stable DNA lesions, that do not affect strand integrity, and are expressed as intermediates of excision repair in stimulated cells, when gap refilling is inhibited by cytosine arabinoside (Ara-C).

  6. Computerized detection of breast lesions in multi-centre and multi-instrument DCE-MR data using 3D principal component maps and template matching

    NASA Astrophysics Data System (ADS)

    Ertas, Gokhan; Doran, Simon; Leach, Martin O.

    2011-12-01

    In this study, we introduce a novel, robust and accurate computerized algorithm based on volumetric principal component maps and template matching that facilitates lesion detection on dynamic contrast-enhanced MR. The study dataset comprises 24 204 contrast-enhanced breast MR images corresponding to 4034 axial slices from 47 women in the UK multi-centre study of MRI screening for breast cancer and categorized as high risk. The scans analysed here were performed on six different models of scanner from three commercial vendors, sited in 13 clinics around the UK. 1952 slices from this dataset, containing 15 benign and 13 malignant lesions, were used for training. The remaining 2082 slices, with 14 benign and 12 malignant lesions, were used for test purposes. To prevent false positives being detected from other tissues and regions of the body, breast volumes are segmented from pre-contrast images using a fast semi-automated algorithm. Principal component analysis is applied to the centred intensity vectors formed from the dynamic contrast-enhanced T1-weighted images of the segmented breasts, followed by automatic thresholding to eliminate fatty tissues and slowly enhancing normal parenchyma and a convolution and filtering process to minimize artefacts from moderately enhanced normal parenchyma and blood vessels. Finally, suspicious lesions are identified through a volumetric sixfold neighbourhood connectivity search and calculation of two morphological features: volume and volumetric eccentricity, to exclude highly enhanced blood vessels, nipples and normal parenchyma and to localize lesions. This provides satisfactory lesion localization. For a detection sensitivity of 100%, the overall false-positive detection rate of the system is 1.02/lesion, 1.17/case and 0.08/slice, comparing favourably with previous studies. This approach may facilitate detection of lesions in multi-centre and multi-instrument dynamic contrast-enhanced breast MR data.

  7. Imaging of Multiple Sclerosis: Role in Neurotherapeutics

    PubMed Central

    Bakshi, Rohit; Minagar, Alireza; Jaisani, Zeenat; Wolinsky, Jerry S.

    2005-01-01

    Summary: Magnetic resonance imaging (MRI) plays an ever-expanding role in the evaluation of multiple sclerosis (MS). This includes its sensitivity for the diagnosis of the disease and its role in identifying patients at high risk for conversion to MS after a first presentation with selected clinically isolated syndromes. In addition, MRI is a key tool in providing primary therapeutic outcome measures for phase I/II trials and secondary outcome measures in phase III trials. The utility of MRI stems from its sensitivity to longitudinal changes including those in overt lesions and, with advanced MRI techniques, in areas affected by diffuse occult disease (the so-called normal-appearing brain tissue). However, all current MRI methodology suffers from limited specificity for the underlying histopathology. Conventional MRI techniques, including lesion detection and measurement of atrophy from T1- or T2-weighted images, have been the mainstay for monitoring disease activity in clinical trials, in which the use of gadolinium with T1-weighted images adds additional sensitivity and specificity for areas of acute inflammation. Advanced imaging methods including magnetization transfer, fluid attenuated inversion recovery, diffusion, magnetic resonance spectroscopy, functional MRI, and nuclear imaging techniques have added to our understanding of the pathogenesis of MS and may provide methods to monitor therapies more sensitively in the future. However, these advanced methods are limited by their cost, availability, complexity, and lack of validation. In this article, we review the role of conventional and advanced imaging techniques with an emphasis on neurotherapeutics. PMID:15897951

  8. Optineurin and amyotrophic lateral sclerosis.

    PubMed

    Maruyama, Hirofumi; Kawakami, Hideshi

    2013-07-01

    Amyotrophic lateral sclerosis is a devastating disease, and thus it is important to identify the causative gene and resolve the mechanism of the disease. We identified optineurin as a causative gene for amyotrophic lateral sclerosis. We found three types of mutations: a homozygous deletion of exon 5, a homozygous Q398X nonsense mutation and a heterozygous E478G missense mutation within its ubiquitin-binding domain. Optineurin negatively regulates the tumor necrosis factor-α-induced activation of nuclear factor kappa B. Nonsense and missense mutations abolished this function. Mutations related to amyotrophic lateral sclerosis also negated the inhibition of interferon regulatory factor-3. The missense mutation showed a cyotoplasmic distribution different from that of the wild type. There are no specific clinical symptoms related to optineurin. However, severe brain atrophy was detected in patients with homozygous deletion. Neuropathologically, an E478G patient showed transactive response DNA-binding protein of 43 kDa-positive neuronal intracytoplasmic inclusions in the spinal and medullary motor neurons. Furthermore, Golgi fragmentation was identified in 73% of this patient's anterior horn cells. In addition, optineurin is colocalized with fused in sarcoma in the basophilic inclusions of amyotrophic lateral sclerosis with fused in sarcoma mutations, and in basophilic inclusion body disease. These findings strongly suggest that optineurin is involved in the pathogenesis of amyotrophic lateral sclerosis.

  9. Hemidystonia secondary to cervical demyelinating lesions.

    PubMed

    Yücesan, C; Tuncel, D; Akbostanci, M C; Yücemen, N; Mutluer, N

    2000-09-01

    Hemidystonia is usually associated with a structural lesion in the contralateral basal ganglia. We report a patient with definite multiple sclerosis, according to Poser's criteria, presenting with an acute-onset sustained left hemidystonia. Cranial T2-weighted magnetic resonance imaging (MRI) showed several hyperintense lesions in the centri semiovali and in the periventricular area without basal ganglia involvement. Moreover cervical spinal cord T2-weighted MRI showed two hyperintense lesions in the left posterolateral spine at C2 and C3, and one lesion in the right posterolateral spine at C4 levels. The hemidystonia improved completely after daily treatment with 1000 mg of methylprednisolone, and cervical MRI was performed after the improvement which showed that the lesions had become smaller and less intense. Finally we consider that the hemidystonia may be caused by the cervical spinal cord lesions of multiple sclerosis. PMID:11054144

  10. Nerve lesioning with direct current

    NASA Astrophysics Data System (ADS)

    Ravid, E. Natalie; Shi Gan, Liu; Todd, Kathryn; Prochazka, Arthur

    2011-02-01

    Spastic hypertonus (muscle over-activity due to exaggerated stretch reflexes) often develops in people with stroke, cerebral palsy, multiple sclerosis and spinal cord injury. Lesioning of nerves, e.g. with phenol or botulinum toxin is widely performed to reduce spastic hypertonus. We have explored the use of direct electrical current (DC) to lesion peripheral nerves. In a series of animal experiments, DC reduced muscle force by controlled amounts and the reduction could last several months. We conclude that in some cases controlled DC lesioning may provide an effective alternative to the less controllable molecular treatments available today.

  11. Evaluation of epiduroscopy for detection of vertebral canal and spinal cord lesions in dogs.

    PubMed

    Garcia-Pereira, Fernando L; Prange, Timo; Seller, Aaron; Obert, Victoria

    2016-07-01

    OBJECTIVE To evaluate the potential usefulness of epiduroscopy for clinical diagnosis and treatment of vertebral canal and spinal cord lesions in dogs. SAMPLE Cadavers of 6 mixed-breed dogs. PROCEDURES Dogs were positioned in sternal recumbency, and an endoscope was introduced into the lumbosacral epidural space. A fiberscope (diameter, 0.9 mm; length, 30 cm) was used for 3 dogs, and a videoscope (diameter, 2.8 mm; length, 70 cm) was used for the other 3 dogs. Visibility and identities of anatomic structures were recorded, and maneuverability of the endoscopes was assessed. Extent of macroscopic tissue damage was evaluated by manual dissection of the vertebral canal at the end of the procedure. RESULTS Intermittent saline (0.9% NaCl) solution infusion, CO2 insufflation, and endoscope navigation improved visualization by separating the epidural fat from the anatomic structures of interest. Images obtained with the fiberscope were small and of poor quality, making identification of specific structures difficult. Maneuverability of the fiberscope was difficult, and target structures could not be reliably reached or identified. Maneuverability and image quality of the videoscope were superior, and spinal nerve roots, spinal dura mater, epidural fat, and blood vessels could be identified. Subsequent manual dissection of the vertebral canal revealed no gross damage in the spinal cord, nerve roots, or blood vessels. CONCLUSIONS AND CLINICAL RELEVANCE A 2.8-mm videoscope was successfully used to perform epiduroscopy through the lumbosacral space in canine cadavers. Additional refinement and evaluation of the technique in live dogs is necessary before its use can be recommended for clinical situations. PMID:27347831

  12. Detection of reduced interhemispheric cortical communication during task execution in multiple sclerosis patients using functional near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Jimenez, Jon J.; Yang, Runze; Nathoo, Nabeela; Varshney, Vishal P.; Golestani, Ali-Mohammad; Goodyear, Bradley G.; Metz, Luanne M.; Dunn, Jeff F.

    2014-07-01

    Multiple sclerosis (MS) impairs brain activity through demyelination and loss of axons. Increased brain activity is accompanied by increases in microvascular hemoglobin oxygen saturation (oxygenation) and total hemoglobin, which can be measured using functional near-infrared spectroscopy (fNIRS). Due to the potentially reduced size and integrity of the white matter tracts within the corpus callosum, it may be expected that MS patients have reduced functional communication between the left and right sides of the brain; this could potentially be an indicator of disease progression. To assess interhemispheric communication in MS, we used fNIRS during a unilateral motor task and the resting state. The magnitude of the change in hemoglobin parameters in the motor cortex was significantly reduced in MS patients during the motor task relative to healthy control subjects. There was also a significant decrease in interhemispheric communication between the motor cortices (expressed as coherence) in MS patients compared to controls during the motor task, but not during the resting state. fNIRS assessment of interhemispheric coherence during task execution may be a useful marker in disorders with white matter damage or axonal loss, including MS.

  13. Molecular detection of Leishmania spp. isolated from cutaneous lesions of patients referred to Herat regional hospital, Afghanistan.

    PubMed

    Mosawi, S H; Dalimi, A

    2016-03-15

    Cutaneous leishmaniasis is one of the main public health problems in Afghanistan, particularly in Herat. To identify Leishmania spp., molecular techniques were applied to samples from 64 cutaneous leishmaniasis patients referred to Herat regional hospital during 2013. Polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis of the ribosomal RNA gene internal transcribed spacer-1 (ITS1) was used. Most of the patients demonstrated dry type single lesions on the head. The results of direct microscopy detection using Giemsastained skin scrapings were compared with that of ITS PCR-RFLP for the diagnosis of cutaneous leishmaniasis. Light microscopy examination showed 37/64 positive cases (58%). PCR revealed 50 positive cases (78%), from which ITS PCR-RFLP identified 48 cases (96%) as L. tropica and 2 cases (4%) as L. major. Cutaneous leishmaniasis in Herat appears to be endemic and of the clinically dry type, caused mainly by L. tropica and occasionally by L. major.

  14. Detection of Cyanotoxins, β-N-methylamino-l-alanine and Microcystins, from a Lake Surrounded by Cases of Amyotrophic Lateral Sclerosis

    PubMed Central

    Banack, Sandra Anne; Caller, Tracie; Henegan, Patricia; Haney, James; Murby, Amanda; Metcalf, James S.; Powell, James; Cox, Paul Alan; Stommel, Elijah

    2015-01-01

    A cluster of amyotrophic lateral sclerosis (ALS) has been previously described to border Lake Mascoma in Enfield, NH, with an incidence of ALS approximating 25 times expected. We hypothesize a possible association with cyanobacterial blooms that can produce β-N-methylamino-l-alanine (BMAA), a neurotoxic amino acid implicated as a possible cause of ALS/PDC in Guam. Muscle, liver, and brain tissue samples from a Lake Mascoma carp, as well as filtered aerosol samples, were analyzed for microcystins (MC), free and protein-bound BMAA, and the BMAA isomers 2,4-diaminobutyric acid (DAB) and N-(2-aminoethyl)glycine (AEG). In carp brain, BMAA and DAB concentrations were 0.043 μg/g ± 0.02 SD and 0.01 μg/g ± 0.002 SD respectively. In carp liver and muscle, the BMAA concentrations were 1.28 μg/g and 1.27 μg/g respectively, and DAB was not detected. BMAA was detected in the air filters, as were the isomers DAB and AEG. These results demonstrate that a putative cause for ALS, BMAA, exists in an environment that has a documented cluster of ALS. Although cause and effect have not been demonstrated, our observations and measurements strengthen the association. PMID:25643180

  15. Detection of trace metallic elements in oral lichenoid contact lesions using SR-XRF, PIXE, and XAFS

    PubMed Central

    Sugiyama, Tomoko; Uo, Motohiro; Wada, Takahiro; Omagari, Daisuke; Komiyama, Kazuo; Miyazaki, Serika; Numako, Chiya; Noguchi, Tadahide; Jinbu, Yoshinori; Kusama, Mikio; Mori, Yoshiyuki

    2015-01-01

    Oral lichen planus (OLP) and oral lichenoid contact lesions (OLCL) are chronic inflammatory mucocutaneous reactions with a risk of malignant transformation that alter the epithelium. OLP and OLCL have similar clinical and histopathological features and it is difficult to distinguish one from the other. Metallic restorations are suspected to generate OLCLs. Trace metal analysis of OLCL specimens may facilitate the discrimination of symptoms and identification of causative metallic restorations. The purpose of this study was to assess OLCL tissue samples for the prevalence of metallic elements derived from dental restorations, and to discriminate OLCL from OLP by using synchrotron radiation-excited X-ray fluorescence analysis (SR-XRF), particle-induced X-ray emission (PIXE), and X-ray absorption fine structure (XAFS). Typical elements of dental materials were detected in the OLCL, whereas no obvious element accumulation was detected in OLP and negative control specimens. The origin of the detected metallic elements was presumed to be dental alloys through erosion. Therefore, our findings support the feasibility of providing supporting information to distinguish OLCL from OLP by using elemental analysis. PMID:26085368

  16. Detection of trace metallic elements in oral lichenoid contact lesions using SR-XRF, PIXE, and XAFS.

    PubMed

    Sugiyama, Tomoko; Uo, Motohiro; Wada, Takahiro; Omagari, Daisuke; Komiyama, Kazuo; Miyazaki, Serika; Numako, Chiya; Noguchi, Tadahide; Jinbu, Yoshinori; Kusama, Mikio; Mori, Yoshiyuki

    2015-06-18

    Oral lichen planus (OLP) and oral lichenoid contact lesions (OLCL) are chronic inflammatory mucocutaneous reactions with a risk of malignant transformation that alter the epithelium. OLP and OLCL have similar clinical and histopathological features and it is difficult to distinguish one from the other. Metallic restorations are suspected to generate OLCLs. Trace metal analysis of OLCL specimens may facilitate the discrimination of symptoms and identification of causative metallic restorations. The purpose of this study was to assess OLCL tissue samples for the prevalence of metallic elements derived from dental restorations, and to discriminate OLCL from OLP by using synchrotron radiation-excited X-ray fluorescence analysis (SR-XRF), particle-induced X-ray emission (PIXE), and X-ray absorption fine structure (XAFS). Typical elements of dental materials were detected in the OLCL, whereas no obvious element accumulation was detected in OLP and negative control specimens. The origin of the detected metallic elements was presumed to be dental alloys through erosion. Therefore, our findings support the feasibility of providing supporting information to distinguish OLCL from OLP by using elemental analysis.

  17. Black holes in multiple sclerosis: definition, evolution, and clinical correlations.

    PubMed

    Sahraian, M A; Radue, E-W; Haller, S; Kappos, L

    2010-07-01

    Magnetic resonance imaging (MRI) is a sensitive paraclinical test for diagnosis and assessment of disease progression in multiple sclerosis (MS) and is often used to evaluate therapeutic efficacy. The formation of new T2-hyperintense MRI lesions is commonly used to measure disease activity, but lacks specificity because edema, inflammation, gliosis, and axonal loss all contribute to T2 lesion formation. As the role of neurodegeneration in the pathophysiology of MS has become more prominent, the formation and evolution of chronic or persistent Tl-hypointense lesions (black holes) have been used as markers of axonal loss and neuronal destruction to measure disease activity. Despite the use of various detection methods, including advanced imaging techniques such as magnetization transfer imaging and magnetic resonance spectroscopy, correlation of persistent black holes with clinical outcomes in patients with MS remains uncertain. Furthermore, although axonal loss and neuronal tissue destruction are known to contribute to irreversible disability in patients with MS, there are limited data on the effect of therapy on longitudinal change in Tl-hypointense lesion volume. Measurement of black holes in clinical studies may elucidate the underlying pathophysiology of MS and may be an additional method of evaluating therapeutic efficacy.

  18. Fatigue and Multiple Sclerosis

    MedlinePlus

    Fatigue - National Multiple Sclerosis Society Skip to navigation Skip to content Menu Navigation National Multiple Sclerosis Society Sign In In Your Area ... help* daily life for: positive-mom* The National MS Society is Here to Help Need More Information? ...

  19. National Multiple Sclerosis Society

    MedlinePlus

    ... Join the Community Stay Informed Corporate Support National Multiple Sclerosis Society Our Mission: People affected by MS can ... 10.5 Million in New Research to Stop Multiple Sclerosis, Restore Function and End MS Forever October 11, ...

  20. Studies on experimental pulmonary granulomas. I. Detection of lymphokines in granulomatous lesions.

    PubMed Central

    Masih, N.; Majeska, J.; Yoshida, T.

    1979-01-01

    Granulomatous reactions were immunologically induced in guinea pigs by several procedures, including intravenous injections of Bacille Calmette Gúerin (BCG) into animals immunized with complete Freund's Adjuvant and an intravenous injection of agarose beads linked to a specific antigen (dinitrophenylated bovine serum albumin) into immune animals. The tissue extracts obtained from lungs at various stages of granuloma formation were examined for macrophage migration inhibition (MIF) activity. The activity was found in a high incidence during the early stages of the granulomatous response. In contrast, MIF activity could be detected only rarely in granulomatous spleens and not in granulomatous livers. Chemotactic factor activity and mitogenic factor activity were only sporadically detectable. The MIF activity was associated with fractions showing chemical heterogeneity. One fraction was physicochemically indistinguishable from conventional lymphocyte-derived MIF; the other was a substance of large molecular weight. These results demonstrate the presence of biologically active mediators in immune granulomas, which may be related to early events involved in the induction or enhancement of such reactions. Images Figure 2 Figure 3 Figure 1 Figure 4 PMID:377991

  1. Effects of dose reduction on the detectability of standardized radiolucent lesions in digital panoramic radiography.

    PubMed

    Dula, K; Sanderink, G; van der Stelt, P F; Mini, R; Buser, D

    1998-08-01

    Dose reduction in digital panoramic radiography was studied. Intentional underexposure was performed with the Orthophos DS while six different human mandibles were radiographed. Exposure settings were 69 kV/15 mA (standard), 64 kV/16 mA, and 60 kV/16 mA. Standardized spherical defects, each either 1 or 1.25 mm in diameter, were simulated in 288 of 432 images, and seven observers decided whether defects were present or not. Areas under the receiver operating characteristics curves were calculated. They showed no significant differences in the detectability of the 1-mm defect at 69, 64, or 60 kV. For the 1.25-mm defect, no difference was found between the 69 and 60 kV images, but a statistically significant different detectability was found for 64 kV images in comparison with both 69 and 60 kV images. A dose reduction of up to 43% was ascertained with a Pedo-RT-Humanoid phantom when panoramic radiography was performed at 60 kV/16 mA. The conclusion is that with the Orthophos DS, it seems possible to reduce the dose rate of x-rays without loss of diagnostic quality in the case of radiolucent changes. PMID:9720100

  2. Effects of dose reduction on the detectability of standardized radiolucent lesions in digital panoramic radiography.

    PubMed

    Dula, K; Sanderink, G; van der Stelt, P F; Mini, R; Buser, D

    1998-08-01

    Dose reduction in digital panoramic radiography was studied. Intentional underexposure was performed with the Orthophos DS while six different human mandibles were radiographed. Exposure settings were 69 kV/15 mA (standard), 64 kV/16 mA, and 60 kV/16 mA. Standardized spherical defects, each either 1 or 1.25 mm in diameter, were simulated in 288 of 432 images, and seven observers decided whether defects were present or not. Areas under the receiver operating characteristics curves were calculated. They showed no significant differences in the detectability of the 1-mm defect at 69, 64, or 60 kV. For the 1.25-mm defect, no difference was found between the 69 and 60 kV images, but a statistically significant different detectability was found for 64 kV images in comparison with both 69 and 60 kV images. A dose reduction of up to 43% was ascertained with a Pedo-RT-Humanoid phantom when panoramic radiography was performed at 60 kV/16 mA. The conclusion is that with the Orthophos DS, it seems possible to reduce the dose rate of x-rays without loss of diagnostic quality in the case of radiolucent changes.

  3. Reassessment of motor-behavioural test analyses enables the detection of early disease-onset in a transgenic mouse model of amyotrophic lateral sclerosis.

    PubMed

    Schäfer, Sabrina; Hermans, Emmanuel

    2011-11-20

    As a model for amyotrophic lateral sclerosis (ALS), transgenic hSOD1(G93A) mice constitute the standard tool for evaluating future therapeutic strategies. Due to axonal retraction from neuromuscular junctions, the animals suffer from muscle wasting leading to weakness and paralysis of the extremities, which in early stages can be detected by measuring weight loss. Suspecting that underlying mechanisms might yield subtle neuromuscular abnormalities ahead of weight loss onset, we wanted to determine a behavioural test to detect disease onset time earlier. We compared the monitoring of weight with the "forced" examination of grip strength and the investigation of freely behaving animals within an open field. Additionally, we compared two different data analysis methods: (1) two-way ANOVA with Bonferroni correction (2) break point analysis calculating symptom onset time points for each animal. Break point analysis revealed onset times that significantly preceded those obtained by standard two-way ANOVA. Open field analysis of freely moving animals could not give an advantage over weight loss measurements. Grip strength assessment of hindlimbs detected disease onset 36 days before the first evidence of weight loss, providing a maximal treatment window of 84 days on average before the death of male animals. We conclude that grip strength analysis of hindlimbs is a very sensitive and reproducible motor behavioural test, which can even be applied to small cohorts of animals. Combined with break point analysis, it represents the method of choice to detect early disease onset in hSOD1(G93A) mice. PMID:21723884

  4. Performance comparisons of planar and volumetric observers for lesion detection in PET scanning

    NASA Astrophysics Data System (ADS)

    Kim, Jae-Seung; Kinahan, Paul E.; Lartizien, Carole; Comtat, Claude; Lewellen, Tom K.

    2003-05-01

    This work presents initial results of comparisons between planar and volumetric observer detection task performances for both human and model observers. Positron Emission Tomography (PET) imaging acquires and reconstructs tomographic images as contiguous volumetric (3D) images. Consequently physicians typically interpret these images by searching the image volume using linked orthogonal planar images in the three standard orientations (transverse, sagittal, and coronal). Most of observer studies, however, have typically used planar images for evaluation. For human observer ROC studies, an observer scoring tool, similar to the display tool being used in clinical PET oncology imaging, has been developed. For model observer studies the non-prewhitening matched filter (NPWMF) and the channelized Hotelling observer (CHO) were used to compute detectabilities as figures-of-merit for class separations. For the volumetric (3D)model observers, the entire image volume is used with appropriate 3D templates. For the planar (2D) model observers the transaxial plane centered on the target sphere is extracted and analyzed using 2D templates. Multiple realizations were generated using a non-Monte Carlo analytic simulator for feasible amount of simulation time and statistically accurate noise properties. For comparisons, the correlations between each model observer and human observer performance are computed. The result showed that 3D model observers have a higher correlation with human observers than 2D observers do when axial smoothing is not applied. With axial smoothing, however, the correlation of 2D model observers in general increased to the level of 3D model observer correlations with the human observer.

  5. Non-Local Means Inpainting of MS Lesions in Longitudinal Image Processing.

    PubMed

    Guizard, Nicolas; Nakamura, Kunio; Coupé, Pierrick; Fonov, Vladimir S; Arnold, Douglas L; Collins, D Louis

    2015-01-01

    In medical imaging, multiple sclerosis (MS) lesions can lead to confounding effects in automatic morphometric processing tools such as registration, segmentation and cortical extraction, and subsequently alter individual longitudinal measurements. Multiple magnetic resonance imaging (MRI) inpainting techniques have been proposed to decrease the impact of MS lesions in medical image processing, however, most of these methods make the assumption that lesions only affect white matter. Here, we propose a method to fill lesion regions using the patch-based non-local mean (NLM) strategy. The method consists of a hierarchical concentric filling strategy after identification of the lesion region. The lesion is filled iteratively, based on the surrounding tissue intensity, using an onion peel strategy. This concentric technique presents the advantage of preserving the local information and therefore the continuity of the anatomy and does not require identification of any a priori normal brain tissues. The method is first evaluated on 20 healthy subjects with simulated artificial MS lesions where we assessed our technique by measuring the peak signal-to-noise ratio (PSNR) of the images with inpainted lesion and the original healthy images. Second, in order to assess the impact of lesion filling on longitudinal image analyses, we performed a power analysis with sample size estimation to evaluate brain atrophy and ventricular growth in patients with MS. The method was compared to two different publicly available methods (FSL lesion fill and Lesion LEAP) and a more classic method, which fills the region with intensities similar to that of the surrounding healthy white matter tissue or mask the lesions. The proposed method was shown to exceed the other methods in reproducing the fidelity of healthy subject images where the lesions were inpainted. The method also improved the power to detect brain atrophy or ventricular growth by decreasing the sample size by 25% in the presence

  6. Non-Local Means Inpainting of MS Lesions in Longitudinal Image Processing

    PubMed Central

    Guizard, Nicolas; Nakamura, Kunio; Coupé, Pierrick; Fonov, Vladimir S.; Arnold, Douglas L.; Collins, D. Louis

    2015-01-01

    In medical imaging, multiple sclerosis (MS) lesions can lead to confounding effects in automatic morphometric processing tools such as registration, segmentation and cortical extraction, and subsequently alter individual longitudinal measurements. Multiple magnetic resonance imaging (MRI) inpainting techniques have been proposed to decrease the impact of MS lesions in medical image processing, however, most of these methods make the assumption that lesions only affect white matter. Here, we propose a method to fill lesion regions using the patch-based non-local mean (NLM) strategy. The method consists of a hierarchical concentric filling strategy after identification of the lesion region. The lesion is filled iteratively, based on the surrounding tissue intensity, using an onion peel strategy. This concentric technique presents the advantage of preserving the local information and therefore the continuity of the anatomy and does not require identification of any a priori normal brain tissues. The method is first evaluated on 20 healthy subjects with simulated artificial MS lesions where we assessed our technique by measuring the peak signal-to-noise ratio (PSNR) of the images with inpainted lesion and the original healthy images. Second, in order to assess the impact of lesion filling on longitudinal image analyses, we performed a power analysis with sample size estimation to evaluate brain atrophy and ventricular growth in patients with MS. The method was compared to two different publicly available methods (FSL lesion fill and Lesion LEAP) and a more classic method, which fills the region with intensities similar to that of the surrounding healthy white matter tissue or mask the lesions. The proposed method was shown to exceed the other methods in reproducing the fidelity of healthy subject images where the lesions were inpainted. The method also improved the power to detect brain atrophy or ventricular growth by decreasing the sample size by 25% in the presence

  7. Clinical significance of hTERC gene amplification detection by FISH in the screening of cervical lesions.

    PubMed

    Zhang, Yuan; Wang, Xiaobei; Ma, Ling; Wang, Zehua; Hu, Lihua

    2009-06-01

    This study evaluated the clinical significance of hTERC gene amplification detection by fluorescence in situ hybridization (FISH) in the screening of cervical lesions. Cervical specimens of 50 high risk patients were detected by thin liquid-based cytology. The patients whose cytological results were classified as ASCUS or above were subjected to the subsequent colposcopic biopsies. Slides prepared from these 50 cervical specimens were analyzed for hTERC gene amplification using interphase FISH with the two-color hTERC probe. The results of the cytological analysis and those of subsequent biopsies, when available, were compared with the FISH-detected hTERC abnormalities. It was found that the positive rates of hTERC gene amplification in NILM, ASCUS, LSIL, HSIL, and SCC groups were 0.00, 28.57%, 57.14%, 100%, and 100%, respectively. The positive rates of hTERC gene amplification in HSIL and SCC groups were significantly higher than those in NILM, ASCUS and LSIL groups (all P<0.05). The mean percentages of cells with hTERC gene amplification in NILM, ASCUS, LSIL, HSIL, and SCC groups were 0.00, 10.50%, 36.00%, 79.00%, and 96.50%, respectively. Patients with HSIL or SCC cytological diagnoses had significantly higher mean percentages of cells with hTERC gene amplification than did patients with NILM, ASCUS or LSIL cytological diagnoses (all P<0.05). It was concluded that two-color interphase FISH could detect hTERC gene amplification to accurately distinguish HSIL and ISIL of cervical cells. It may be an adjunct to cytology screening, especially high-risk patients.

  8. Multiple sclerosis

    PubMed Central

    Boster, Aaron L.; Racke, Michael K.

    2013-01-01

    Summary Preliminary studies have suggested that a high salt diet may play a role in the development of autoimmune disease and possibly multiple sclerosis (MS). Promising clinical trial results for 2 new therapies for MS have been reported. Dimethyl fumarate, also known by its investigational name BG-12, became the third oral disease-modifying therapy for MS to be Food and Drug Administration (FDA)–approved in March 2013. Interestingly, dimethyl fumarate served as the active compound used for the treatment of psoriasis for decades. Alemtuzumab remains under investigation and is not currently FDA-approved for treatment of MS. Other drugs currently approved for alternative indications are being investigated for use in MS. Additionally, an investigation of alternative dosing strategies for glatiramer acetate suggests that patients may benefit from a higher dose formulation and less frequent medication administration. Advances in basic science research have identified another potential autoantigenic target in MS, KIR4.1, which may provide further insight into MS pathophysiology. PMID:24175156

  9. Photoacoustic detection and optical spectroscopy of high-intensity focused ultrasound-induced thermal lesions in biologic tissue

    SciTech Connect

    Alhamami, Mosa; Kolios, Michael C.; Tavakkoli, Jahan

    2014-05-15

    Purpose: The aims of this study are: (a) to investigate the capability of photoacoustic (PA) method in detecting high-intensity focused ultrasound (HIFU) treatments in muscle tissuesin vitro; and (b) to determine the optical properties of HIFU-treated and native tissues in order to assist in the interpretation of the observed contrast in PA detection of HIFU treatments. Methods: A single-element, spherically concaved HIFU transducer with a centre frequency of 1 MHz was utilized to create thermal lesions in chicken breast tissuesin vitro. To investigate the detectability of HIFU treatments photoacoustically, PA detection was performed at 720 and 845 nm on seven HIFU-treated tissue samples. Within each tissue sample, PA signals were acquired from 22 locations equally divided between two regions of interest within two volumes in tissue – a HIFU-treated volume and an untreated volume. Optical spectroscopy was then carried out on 10 HIFU-treated chicken breast specimens in the wavelength range of 500–900 nm, in 1-nm increments, using a spectrophotometer with an integrating sphere attachment. The authors’ optical spectroscopy raw data (total transmittance and diffuse reflectance) were used to obtain the optical absorption and reduced scattering coefficients of HIFU-induced thermal lesions and native tissues by employing the inverse adding-doubling method. The aforementioned interaction coefficients were subsequently used to calculate the effective attenuation coefficient and light penetration depth of HIFU-treated and native tissues in the wavelength range of 500–900 nm. Results: HIFU-treated tissues produced greater PA signals than native tissues at 720 and 845 nm. At 720 nm, the averaged ratio of the peak-to-peak PA signal amplitude of HIFU-treated tissue to that of native tissue was 3.68 ± 0.25 (mean ± standard error of the mean). At 845 nm, the averaged ratio of the peak-to-peak PA signal amplitude of HIFU-treated tissue to that of native tissue was 3.75

  10. Detection and characterization of human tissue lesions with near-infrared Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Feld, Michael S.; Manoharan, Ramasamy; Salenius, Juha; Orenstein-Carndona, Jacobo; Roemer, Tjeerd J.; Brennan, James F., III; Dasari, Ramachandra R.; Wang, Yang

    1995-05-01

    Near infrared (NIR) Raman spectroscopy provides a powerful method for quantitative histochemistry of human tissue and disease diagnosis. The feasibility and potential of this technique for in situ histochemical analysis of human coronary artery has been demonstrated and presented in other reports from our laboratory. In this work, we review recent results obtained with the NIR Raman spectroscopy on a variety of tissue types studied at the MIT Laser Biomedical Research Center. We have collected NIR Raman spectra from colon, bladder, breast, and carotid artery. For colon, bladder and breast, consistent differences between carcinoma and normal tissue spectra were observed. For colon and bladder, the spectral differences appear to be due to an increased content of nucleic acid in carcinomas, while the spectral changes in malignant breast tissue are associated with an increase of protein content. Spectra from carotid artery have similar features as those from aorta and coronary arteries. We also show some preliminary results obtained with a NIR Raman microspectroscopy setup with 20 micron lateral resolution. The biochemical distributions for normal and diseased regions on the same tissue samples are observed. The potential of using this NIR Raman spectroscopy for detection and characterization of carcinoma and atherosclerosis, is discussed.

  11. Comparison of the channelized Hotelling and human observers for lesion detection in hepatic SPECT imaging

    NASA Astrophysics Data System (ADS)

    King, Michael A.; de Vries, Daniel J.; Soares, Edward J.

    1997-04-01

    The relative rankings of the channelized Hotelling model observer were compared to those of the human observers for the task of detecting 'hot' tumors in simulated hepatic SPECT slices. The signal-to-noise ratios (SNRs) were determined using eighty images for each of three slice locations. The acquisition and processing strategies investigated were: (1) imaging solely primary photons, (2) imaging primary plus scatter within a 20% symmetric energy window for Tc-99m, (3) imaging with primary plus an elevated amount of scatter, (4) energy-spectrum-based scatter compensation of the primary plus scatter acquisitions, and (5) energy-spectrum-based scatter compensation of the acquisitions with an elevated amount of scatter. Both square non-overlapping channels (SQR), and overlapping difference- of-Gaussian channels (DOG) were incorporated into the Hotelling model observer. When the scatter compensation results were excluded, both channelized Hotelling model observers exhibited a strong correlation with the rankings of the human-observers. With the inclusion of the scatter compensation results, only with the DOG model observer was the null-hypothesis of no correlation rejected at the p equals 0.05 level. It is concluded that further investigation of the channel model used with the Hotelling observer is indicated to determine if better correlation can be obtained.

  12. Optimization of primer design for the detection of variable genomic lesions in cancer.

    PubMed

    Bashir, Ali; Liu, Yu-Tsueng; Raphael, Benjamin J; Carson, Dennis; Bafna, Vineet

    2007-11-01

    Primer approximation multiplex PCR (PAMP) is a new experimental protocol for efficiently assaying structural variation in genomes. PAMP is particularly suited to cancer genomes where the precise breakpoints of alterations such as deletions or translocations vary between patients. The design of PCR primer sets for PAMP is challenging because a large number of primer pairs are required to detect alterations in the hundreds of kilobases range that can occur in cancer. These sets of primers must achieve high coverage of the region of interest, while avoiding primer dimers and satisfying the physico-chemical constraints of good PCR primers. We describe a natural formulation of these constraints as a combinatorial optimization problem. We show that the PAMP primer design problem is NP-hard, and design algorithms based on simulated annealing and integer programming, that provide good solutions to this problem in practice. The algorithms are applied to a test region around the known CDKN2A deletion, which show excellent results even in a 1:49 mixture of mutated:wild-type cells. We use these test results to help set design parameters for larger problems. We can achieve near-optimal designs for regions close to 1 Mb. PMID:17766270

  13. Detection of human cytomegalovirus and Epstein-Barr Virus in symptomatic and asymptomatic apical periodontitis lesions by real-time PCR

    PubMed Central

    Ozbek, Selcuk M.; Yavuz, Muhammed S.

    2013-01-01

    Objectives: Recent studies have investigated the occurrence of human cytomegalovirus and Epstein-Barr Virus in samples from apical periodontitis lesions and a role in the pathogenesis of this disease has been suggested. Because genotype distribution and seroprevalence of EBV and HCMV differ among populations, it is important to determine the presence of these viruses in endodontic periapical lesions of different populations. The aims of this study were to determine the presence of HCMV and EBV DNAs in samples from Turkish patients with symptomatic and asymptomatic apical periodontitis lesions using real-time polymerase chain reaction method and to evaluate their presence in both symptomatic and asymptomatic apical periodontitis lesions. Study Design: Periapical samples were collected from 12 asymptomatic and 16 symptomatic periapical lesions in conjunction with apicectomy. HCMV and EBV DNAs were identified in the samples by real-time PCR. The chi-squared test with Yates’s correction or the Fisher’s exact test was used to analyse the significance of differences. Results: HCMV DNA was detected in 10 of the 16 (62.5%) symptomatic and in five of the 12 (41.7 %) asymptomatic periapical study lesions. The EBV DNA was identified in seven of the 16 (43.7 %) symptomatic and three of the 12 (25 %) asymptomatic periapical lesions. The difference in occurrence of HCMV and EBV DNA between symptomatic and asymptomatic periapical lesions was not statistically significant. (All comparisons have p > 0.05). Conclusions: Our findings suggest that HCMV and EBV is a frequent inhabitant of both symptomatic and asymptomatic apical periodontitis lesions of endodontic origin in Turkish population. Key words:Human cytomegalovirus, Epstein-Barr Virus, apical periodontitis, Polymerase chain reaction method. PMID:23722135

  14. Detection of Primary Malignancy and Metastases with FDG PET/CT in Patients with Cholangiocarcinomas: Lesion-based Comparison with Contrast Enhanced CT

    PubMed Central

    Elias, Youssef; Mariano, Aladin T.; Lu, Yang

    2016-01-01

    The current National Comprehensive Cancer Network (NCCN) Guidelines consider the role of 2-deoxy-2-18F-fluoro-d-glucose positron emission tomography/computer tomography (FDG PET/CT) in the evaluation of cholangiocarcinoma (CCA) as "uncertain," and have recommended contrast enhanced computed tomography (CECT) but not FDG PET/CT as a routine imaging test for CCA workup. We set out to compare the diagnostic performance of FDG PET/CT and CECT in patients with CCA. The retrospective study included patients with CCA who underwent FDG PET/CT and CECT within 2-month interval between 2011 and 2013 in our hospital. Lesion-based comparison was conducted. Final diagnoses were made based on the composite clinical and imaging data with minimal 6-month follow-up. A total of 18 patients with 28-paired tests were included. There is a total of 142 true malignant lesions as revealed by the 6-paired pre-treatment and 22-paired post-treatment tests. On a lesion-based analysis, the sensitivities, specificities, positive predictive values (PPVs), negative predictive values (NPVs), and accuracies of PET/CT and CECT for detection of CCA were 96.5%, 55.5%, 97.2%, 50.0%, 94.1% and 62.2%, 66.7%, 96.7%, 10.0%, 62.5%, respectively. FDG PET/CT detected more intrahepatic malignant and extrahepatic metastases; and had significant higher sensitivity, NPV, and accuracy than CECT, while similar in specificity and PPV. No true positive lesion detected on CECT that was missed on PET/CT, and none of the false negative lesions on PET/CT were detected on CECT. Six patients had paired pretreatment tests, and FDG PET/CT results changed planned management in three patients. Our data suggest that FDG PET/CT detect more primary and metastatic lesions and lead to considerable changes in treatment plan in comparison with CECT. PMID:27651736

  15. Detection of Primary Malignancy and Metastases with FDG PET/CT in Patients with Cholangiocarcinomas: Lesion-based Comparison with Contrast Enhanced CT

    PubMed Central

    Elias, Youssef; Mariano, Aladin T.; Lu, Yang

    2016-01-01

    The current National Comprehensive Cancer Network (NCCN) Guidelines consider the role of 2-deoxy-2-18F-fluoro-d-glucose positron emission tomography/computer tomography (FDG PET/CT) in the evaluation of cholangiocarcinoma (CCA) as "uncertain," and have recommended contrast enhanced computed tomography (CECT) but not FDG PET/CT as a routine imaging test for CCA workup. We set out to compare the diagnostic performance of FDG PET/CT and CECT in patients with CCA. The retrospective study included patients with CCA who underwent FDG PET/CT and CECT within 2-month interval between 2011 and 2013 in our hospital. Lesion-based comparison was conducted. Final diagnoses were made based on the composite clinical and imaging data with minimal 6-month follow-up. A total of 18 patients with 28-paired tests were included. There is a total of 142 true malignant lesions as revealed by the 6-paired pre-treatment and 22-paired post-treatment tests. On a lesion-based analysis, the sensitivities, specificities, positive predictive values (PPVs), negative predictive values (NPVs), and accuracies of PET/CT and CECT for detection of CCA were 96.5%, 55.5%, 97.2%, 50.0%, 94.1% and 62.2%, 66.7%, 96.7%, 10.0%, 62.5%, respectively. FDG PET/CT detected more intrahepatic malignant and extrahepatic metastases; and had significant higher sensitivity, NPV, and accuracy than CECT, while similar in specificity and PPV. No true positive lesion detected on CECT that was missed on PET/CT, and none of the false negative lesions on PET/CT were detected on CECT. Six patients had paired pretreatment tests, and FDG PET/CT results changed planned management in three patients. Our data suggest that FDG PET/CT detect more primary and metastatic lesions and lead to considerable changes in treatment plan in comparison with CECT.

  16. Detection of Primary Malignancy and Metastases with FDG PET/CT in Patients with Cholangiocarcinomas: Lesion-based Comparison with Contrast Enhanced CT.

    PubMed

    Elias, Youssef; Mariano, Aladin T; Lu, Yang

    2016-09-01

    The current National Comprehensive Cancer Network (NCCN) Guidelines consider the role of 2-deoxy-2-(18)F-fluoro-d-glucose positron emission tomography/computer tomography (FDG PET/CT) in the evaluation of cholangiocarcinoma (CCA) as "uncertain," and have recommended contrast enhanced computed tomography (CECT) but not FDG PET/CT as a routine imaging test for CCA workup. We set out to compare the diagnostic performance of FDG PET/CT and CECT in patients with CCA. The retrospective study included patients with CCA who underwent FDG PET/CT and CECT within 2-month interval between 2011 and 2013 in our hospital. Lesion-based comparison was conducted. Final diagnoses were made based on the composite clinical and imaging data with minimal 6-month follow-up. A total of 18 patients with 28-paired tests were included. There is a total of 142 true malignant lesions as revealed by the 6-paired pre-treatment and 22-paired post-treatment tests. On a lesion-based analysis, the sensitivities, specificities, positive predictive values (PPVs), negative predictive values (NPVs), and accuracies of PET/CT and CECT for detection of CCA were 96.5%, 55.5%, 97.2%, 50.0%, 94.1% and 62.2%, 66.7%, 96.7%, 10.0%, 62.5%, respectively. FDG PET/CT detected more intrahepatic malignant and extrahepatic metastases; and had significant higher sensitivity, NPV, and accuracy than CECT, while similar in specificity and PPV. No true positive lesion detected on CECT that was missed on PET/CT, and none of the false negative lesions on PET/CT were detected on CECT. Six patients had paired pretreatment tests, and FDG PET/CT results changed planned management in three patients. Our data suggest that FDG PET/CT detect more primary and metastatic lesions and lead to considerable changes in treatment plan in comparison with CECT. PMID:27651736

  17. Amyotrophic lateral sclerosis: early contributions of Jean-Martin Charcot.

    PubMed

    Goetz, C G

    2000-03-01

    Amyotrophic lateral sclerosis is historically an important entity because its manifestations involve distinct signs that can be correlated with gray and white matter lesions at specific sites within the central nervous system. Working at the end of the nineteenth century, the celebrated neurologist, Jean-Martin Charcot, used this disorder as a prototypic example of the power of his research method, termed "méthode anatomoclinique." Using clinical cases and autopsy material, he showed how anatomical lesions in the nervous system could be accurately determined by the presence of carefully analyzed clinical signs. Charcot's work on amyotrophic lateral sclerosis brought together neurological entities formerly considered as disparate disorders, primary amyotrophy and primary lateral sclerosis. In addition, these studies contributed to the understanding of spinal cord and brain stem anatomy and the organization of the normal nervous system. Because of Charcot's fundamental contributions, the eponym "Charcot's disease" has been used internationally in association with amyotrophic lateral sclerosis.

  18. In vivo detection of free radicals using molecular MRI and immuno-spin trapping in a mouse model for amyotrophic lateral sclerosis.

    PubMed

    Towner, Rheal A; Smith, Nataliya; Saunders, Debra; Lupu, Florea; Silasi-Mansat, Robert; West, Melinda; Ramirez, Dario C; Gomez-Mejiba, Sandra E; Bonini, Marcelo G; Mason, Ronald P; Ehrenshaft, Marilyn; Hensley, Kenneth

    2013-10-01

    Free radicals associated with oxidative stress play a major role in amyotrophic lateral sclerosis (ALS). By combining immuno-spin trapping and molecular magnetic resonance imaging, in vivo trapped radical adducts were detected in the spinal cords of SOD1(G93A)-transgenic (Tg) mice, a model for ALS. For this study, the nitrone spin trap DMPO (5,5-dimethyl-1-pyrroline N-oxide) was administered (ip) over 5 days before administration (iv) of an anti-DMPO probe (anti-DMPO antibody covalently bound to an albumin-gadolinium-diethylenetriamine pentaacetic acid-biotin MRI contrast agent) to trap free radicals. MRI was used to detect the presence of the anti-DMPO radical adducts by a significant sustained increase in MR signal intensities (p < 0.05) or anti-DMPO probe concentrations measured from T₁ relaxations (p < 0.01). The biotin moiety of the anti-DMPO probe was targeted with fluorescence-labeled streptavidin to locate the probe in excised tissues. Negative controls included either Tg ALS mice initially administered saline rather than DMPO followed by the anti-DMPO probe or non-Tg mice initially administered DMPO and then the anti-DMPO probe. The anti-DMPO probe was found to bind to neurons via colocalization fluorescence microscopy. DMPO adducts were also confirmed in diseased/nondiseased tissues from animals administered DMPO. Apparent diffusion coefficients from diffusion-weighted images of spinal cords from Tg mice were significantly elevated (p < 0.001) compared to wild-type controls. This is the first report regarding the detection of in vivo trapped radical adducts in an ALS model. This novel, noninvasive, in vivo diagnostic method can be applied to investigate the involvement of free radical mechanisms in ALS rodent models.

  19. Polymerase chain reaction (PCR) and sequence specific oligonucleotide probes (SSOP) genotyping assay for detection of genes associated with rheumatoid arthritis and multiple sclerosis.

    PubMed

    Nikolaou, Konstantina; Kalatzis, Fanis G; Giannakeas, Nikolaos; Markoula, Sofia; Chatzikyriakidou, Anthi; Georgiou, Ioannis; Fotiadis, Dimitrios I

    2010-01-01

    In this paper an assay for the detection of genes associated with rheumatoid arthritis (RA) and multiple sclerosis, using polymerase chain reaction (PCR) and sequence specific oligonucleotide probes (SSOP) is presented, in order to be further applied in a portable Lab-On-Chip (LOC) device. A substantial part of these reagents were based on the literature (11th International Histocompatibility Workshop, IHW), bearing the advantage of proven successful implementation in genotyping, while others were designed for this study. More precisely, our methodology discriminates HLA-DRB1 as DRB1*01, *04 and *10, which include shared epitope (SE) alleles associated with RA and additionally DRB1*15 allele, including DRB1*1501 associated with MS (broad genotyping method). To further present the basic elements of the assay for high resolution genotyping of SE DRB1 alleles, we provide as an example the case of HLA-DRB1*10 alleles (HLADRB1* 100101, *100102, *100103, *1002 and *1003). Regarding the methodology for developing a detection assay, for SNPs associated with RA or MS the basic steps are presented. DNA sequence data are obtained from IMGT/HLA and SNP database. Online software tools are used to define hybridization specificity of primers and probes towards human DNA, leading to hybridization patterns that uniquely designate a target allele and evaluate parameters influencing PCR efficiency. Respecting current technological limitations of autonomous molecular-based LOC systems the approach of broad genotyping of HLA-DRB1*01/*04/*10/*15 genes, is intended to be initially used, leaving, high resolution genotyping of SE alleles for future implementations. This method is easy to be updated and extended to detect additional associated loci with RA or MS.

  20. Interaction Study of Phospholipid Membranes with an N-Glucosylated β-Turn Peptide Structure Detecting Autoantibodies Biomarkers of Multiple Sclerosis.

    PubMed

    Becucci, Lucia; Benci, Stefano; Nuti, Francesca; Real-Fernandez, Feliciana; Vaezi, Zahra; Stella, Lorenzo; Venanzi, Mariano; Rovero, Paolo; Papini, Anna Maria

    2015-01-01

    The interaction of lipid environments with the type I' β-turn peptide structure called CSF114 and its N-glucosylated form CSF114(Glc), previously developed as a synthetic antigenic probe recognizing specific autoantibodies in a subpopulation of multiple sclerosis patients' serum, was investigated by fluorescence spectroscopy and electrochemical experiments using large unilamellar vesicles, mercury supported lipid self-assembled monolayers (SAMs) and tethered bilayer lipid membranes (tBLMs). The synthetic antigenic probe N-glucosylated peptide CSF114(Glc) and its unglucosylated form interact with the polar heads of lipid SAMs of dioleoylphosphatidylcholine at nonzero transmembrane potentials, probably establishing a dual electrostatic interaction of the trimethylammonium  and phosphate groups of the phosphatidylcholine polar head with the Glu⁵ and His⁸ residues on the opposite ends of the CSF114(Glc) β-turn encompassing residues 6-9. His⁸ protonation at pH 7 eliminates this dual interaction. CSF114(Glc) is adsorbed on top of SAMs of mixtures of dioleoylphosphatidylcholine with sphingomyelin, an important component of myelin, whose proteins are hypothesized to undergo an aberrant N-glucosylation triggering the autoimmune response. Incorporation of the type I' β-turn peptide structure CSF114 into lipid SAMs by potential scans of electrochemical impedance spectroscopy induces defects causing a slight permeabilization toward cadmium ions. The N-glucopeptide CSF114(Glc) does not affect  tBLMs to a detectable extent. PMID:26437433

  1. Interaction Study of Phospholipid Membranes with an N-Glucosylated β-Turn Peptide Structure Detecting Autoantibodies Biomarkers of Multiple Sclerosis

    PubMed Central

    Becucci, Lucia; Benci, Stefano; Nuti, Francesca; Real-Fernandez, Feliciana; Vaezi, Zahra; Stella, Lorenzo; Venanzi, Mariano; Rovero, Paolo; Papini, Anna Maria

    2015-01-01

    The interaction of lipid environments with the type I’ β-turn peptide structure called CSF114 and its N-glucosylated form CSF114(Glc), previously developed as a synthetic antigenic probe recognizing specific autoantibodies in a subpopulation of multiple sclerosis patients’ serum, was investigated by fluorescence spectroscopy and electrochemical experiments using large unilamellar vesicles, mercury supported lipid self-assembled monolayers (SAMs) and tethered bilayer lipid membranes (tBLMs). The synthetic antigenic probe N-glucosylated peptide CSF114(Glc) and its unglucosylated form interact with the polar heads of lipid SAMs of dioleoylphosphatidylcholine at nonzero transmembrane potentials, probably establishing a dual electrostatic interaction of the trimethylammonium  and phosphate groups of the phosphatidylcholine polar head with the Glu5 and His9 residues on the opposite ends of the CSF114(Glc) β-turn encompassing residues 6-9. His9 protonation at pH 7 eliminates this dual interaction. CSF114(Glc) is adsorbed on top of SAMs of mixtures of dioleoylphosphatidylcholine with sphingomyelin, an important component of myelin, whose proteins are hypothesized to undergo an aberrant N-glucosylation triggering the autoimmune response. Incorporation of the type I’ β-turn peptide structure CSF114 into lipid SAMs by potential scans of electrochemical impedance spectroscopy induces defects causing a slight permeabilization toward cadmium ions. The N-glucopeptide CSF114(Glc) does not affect  tBLMs to a detectable extent. PMID:26437433

  2. Interaction Study of Phospholipid Membranes with an N-Glucosylated β-Turn Peptide Structure Detecting Autoantibodies Biomarkers of Multiple Sclerosis.

    PubMed

    Becucci, Lucia; Benci, Stefano; Nuti, Francesca; Real-Fernandez, Feliciana; Vaezi, Zahra; Stella, Lorenzo; Venanzi, Mariano; Rovero, Paolo; Papini, Anna Maria

    2015-09-30

    The interaction of lipid environments with the type I' β-turn peptide structure called CSF114 and its N-glucosylated form CSF114(Glc), previously developed as a synthetic antigenic probe recognizing specific autoantibodies in a subpopulation of multiple sclerosis patients' serum, was investigated by fluorescence spectroscopy and electrochemical experiments using large unilamellar vesicles, mercury supported lipid self-assembled monolayers (SAMs) and tethered bilayer lipid membranes (tBLMs). The synthetic antigenic probe N-glucosylated peptide CSF114(Glc) and its unglucosylated form interact with the polar heads of lipid SAMs of dioleoylphosphatidylcholine at nonzero transmembrane potentials, probably establishing a dual electrostatic interaction of the trimethylammonium  and phosphate groups of the phosphatidylcholine polar head with the Glu⁵ and His⁸ residues on the opposite ends of the CSF114(Glc) β-turn encompassing residues 6-9. His⁸ protonation at pH 7 eliminates this dual interaction. CSF114(Glc) is adsorbed on top of SAMs of mixtures of dioleoylphosphatidylcholine with sphingomyelin, an important component of myelin, whose proteins are hypothesized to undergo an aberrant N-glucosylation triggering the autoimmune response. Incorporation of the type I' β-turn peptide structure CSF114 into lipid SAMs by potential scans of electrochemical impedance spectroscopy induces defects causing a slight permeabilization toward cadmium ions. The N-glucopeptide CSF114(Glc) does not affect  tBLMs to a detectable extent.

  3. Early detection of motor dysfunction in the SOD1G93A mouse model of Amyotrophic Lateral Sclerosis (ALS) using home cage running wheels.

    PubMed

    Bennett, Ellen J; Mead, Richard J; Azzouz, Mimoun; Shaw, Pamela J; Grierson, Andrew J

    2014-01-01

    The SOD1G93A mouse has been used since 1994 for preclinical testing in amyotrophic lateral sclerosis (ALS). Despite recent genetic advances in our understanding of ALS, transgenic mice expressing mutant SOD1 remain the best available, and most widely used, vertebrate model of the disease. We previously described an optimised and rapid approach for preclinical studies in the SOD1G93A mouse. Here we describe improvements to this approach using home cage running wheels to obtain daily measurements of motor function, with minimal intervention. We show that home cage running wheels detect reductions in motor function at a similar time to the rotarod test, and that the data obtained are less variable allowing the use of smaller groups of animals to obtain satisfactory results. This approach refines use of the SOD1G93A model, and reduces the number of animals undergoing procedures of substantial severity, two central principles of the 3Rs (replacement, reduction and refinement of animal use in research). The small group sizes and rapid timescales enable affordable large-scale therapeutic pre-screening in the SOD1G93A mouse, as well as rapid validation of published positive effects in a second laboratory, one of the major stumbling blocks in ALS preclinical therapy development.

  4. Fetal and maternal manifestations of tuberous sclerosis complex: Value of fetal MRI.

    PubMed

    Goel, Reema; Aggarwal, Nishant; Lemmon, Monica E; Bosemani, Thangamadhan

    2016-02-01

    Tuberous sclerosis complex (TSC) is a genetic disorder characterized by benign hamartomas in various organ systems of the body. Prenatal screening of fetuses of mothers affected with TSC using ultrasonography (US) may detect cardiac lesions. Fetal US is not sensitive for evaluation of the brain. We describe brain MRI findings in a fetus with cardiac rhabdomyomas identified on prenatal screening US. Postnatal brain MRI at 5 days of age demonstrated fetal MRI findings without significant added information. Fetal MRI is the imaging modality of choice for evaluation of cerebral manifestations of TSC. Maternal manifestations of TSC in the abdomen or pelvis may also be demonstrated on fetal MRI. PMID:26838171

  5. Individual Assessment of Brain Tissue Changes in MS and the Effect of Focal Lesions on Short-Term Focal Atrophy Development in MS: A Voxel-Guided Morphometry Study

    PubMed Central

    Fox, Jan; Kraemer, Matthias; Schormann, Thorsten; Dabringhaus, Andreas; Hirsch, Jochen; Eisele, Philipp; Szabo, Kristina; Weiss, Christel; Amann, Michael; Weier, Katrin; Naegelin, Yvonne; Kappos, Ludwig; Gass, Achim

    2016-01-01

    We performed voxel-guided morphometry (VGM) investigating the mechanisms of brain atrophy in multiple sclerosis (MS) related to focal lesions. VGM maps detect regional brain changes when comparing 2 time points on high resolution T1-weighted (T1w) magnetic resonace imaging (MRI). Two T1w MR datasets from 92 relapsing-remitting MS patients obtained 12 months apart were analysed with VGM. New lesions and volume changes of focal MS lesions as well as in the surrounding tissue were identified by visual inspection on colour coded VGM maps. Lesions were dichotomized in active and inactive lesions. Active lesions, defined by either new lesions (NL) (volume increase > 5% in VGM), chronic enlarging lesions (CEL) (pre-existent T1w lesions with volume increase > 5%), or chronic shrinking lesions (CSL) (pre-existent T1w lesions with volume reduction > 5%) in VGM, were accompanied by tissue shrinkage in surrounding and/or functionally related regions. Volume loss within the corpus callosum was highly correlated with the number of lesions in its close proximity. Volume loss in the lateral geniculate nucleus was correlated with lesions along the optic radiation. VGM analysis provides strong evidence that all active lesion types (NL, CEL, and CSL) contribute to brain volume reduction in the vicinity of lesions and/or in anatomically and functionally related areas of the brain. PMID:27043553

  6. Pursuing shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) for concomitant detection of breast lesions and microcalcifications

    NASA Astrophysics Data System (ADS)

    Zheng, Chao; Shao, Wanting; Paidi, Santosh Kumar; Han, Bing; Fu, Tong; Wu, Di; Bi, Lirong; Xu, Weiqing; Fan, Zhimin; Barman, Ishan

    2015-10-01

    Although tissue staining followed by morphologic identification remains the gold standard for diagnosis of most cancers, such determinations relying solely on morphology are often hampered by inter- and intra-observer variability. Vibrational spectroscopic techniques, in contrast, offer objective markers for diagnoses and can afford disease detection prior to alterations in cellular and extracellular architecture by furnishing a rapid ``omics''-like view of the biochemical status of the probed specimen. Here, we report a classification approach to concomitantly detect microcalcification status and local pathological state in breast tissue, featuring a combination of vibrational spectroscopy that focuses on the tumor and its microenvironment, and multivariate data analysis of spectral markers reflecting molecular expression. We employ the unprecedented sensitivity and exquisite molecular specificity offered by Au@SiO2 shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) to probe the presence of calcified deposits and distinguish between normal breast tissues, fibroadenoma, atypical ductal hyperplasia, ductal carcinoma in situ (DCIS), and invasive ductal carcinoma (IDC). By correlating the spectra with the corresponding histologic assessment, we developed partial least squares-discriminant analysis derived decision algorithm that provides excellent diagnostic power in the fresh frozen sections (overall accuracy of 99.4% and 93.6% using SHINs for breast lesions with and without microcalcifications, respectively). The performance of this decision algorithm is competitive with or supersedes that of analogous algorithms employing spontaneous Raman spectroscopy while enabling facile detection due to the considerably higher intensity of SHINERS. Our results pave the way for rapid tissue spectral pathology measurements using SHINERS that can offer a novel stain-free route to accurate and economical diagnoses without human interpretation.Although tissue staining

  7. Pursuing shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) for concomitant detection of breast lesions and microcalcifications.

    PubMed

    Zheng, Chao; Shao, Wanting; Paidi, Santosh Kumar; Han, Bing; Fu, Tong; Wu, Di; Bi, Lirong; Xu, Weiqing; Fan, Zhimin; Barman, Ishan

    2015-10-28

    Although tissue staining followed by morphologic identification remains the gold standard for diagnosis of most cancers, such determinations relying solely on morphology are often hampered by inter- and intra-observer variability. Vibrational spectroscopic techniques, in contrast, offer objective markers for diagnoses and can afford disease detection prior to alterations in cellular and extracellular architecture by furnishing a rapid "omics"-like view of the biochemical status of the probed specimen. Here, we report a classification approach to concomitantly detect microcalcification status and local pathological state in breast tissue, featuring a combination of vibrational spectroscopy that focuses on the tumor and its microenvironment, and multivariate data analysis of spectral markers reflecting molecular expression. We employ the unprecedented sensitivity and exquisite molecular specificity offered by Au@SiO2 shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) to probe the presence of calcified deposits and distinguish between normal breast tissues, fibroadenoma, atypical ductal hyperplasia, ductal carcinoma in situ (DCIS), and invasive ductal carcinoma (IDC). By correlating the spectra with the corresponding histologic assessment, we developed partial least squares-discriminant analysis derived decision algorithm that provides excellent diagnostic power in the fresh frozen sections (overall accuracy of 99.4% and 93.6% using SHINs for breast lesions with and without microcalcifications, respectively). The performance of this decision algorithm is competitive with or supersedes that of analogous algorithms employing spontaneous Raman spectroscopy while enabling facile detection due to the considerably higher intensity of SHINERS. Our results pave the way for rapid tissue spectral pathology measurements using SHINERS that can offer a novel stain-free route to accurate and economical diagnoses without human interpretation. PMID:26415633

  8. Vision Disturbances in Multiple Sclerosis.

    PubMed

    Costello, Fiona

    2016-04-01

    Visual disturbances are frequently encountered in multiple sclerosis (MS), and include problems with how affected individuals see the world (afferent visual pathway symptoms) and how their eyes move together (efferent visual pathway disorders). Optic neuritis is the most common afferent visual pathway manifestation of MS, from which visual recovery is often incomplete. Visual field defects caused by lesions in the retrochiasmal or retrogeniculate regions of the afferent visual pathway also occur, albeit less frequently. Efferent visual pathway lesions causing ocular misalignment and nystagmus may lead to diplopia and oscillopsia, respectively. Vision loss has a major impact on perceptions regarding quality of life in MS. Therefore, it is important for clinicians to be able to identify and localize the underlying basis of visual disturbances to provide the best care possible for their patients. PMID:27116725

  9. Detection of DNA alkylphosphotriesters by 32P postlabeling: evidence for the nonrandom manifestation of phosphotriester lesions in vivo.

    PubMed

    Guichard, Y; Jones, G D; Farmer, P B

    2000-03-01

    Many genotoxic carcinogens react with the sugar-phosphate backbone in DNA to form phosphotriester (PTE) adducts. These lesions are relatively abundant and persistent for some alkylating carcinogens and may therefore serve as useful biomarkers with which to assess genotoxic exposure and potential mutagenic risk. In the present study, we have developed a 32p postlabeling method that permits analysis of total methyl and/or ethyl PTE in DNA at the femtomole level. The technique is based on the inability of all known nucleolytic enzymes to cleave the internucleotide PTE bond. Consequently, complete digestion of alkylated DNA with these nucleases in the presence of an alkaline phosphatase yields PTE-dinucleoside phosphates. These species are then converted to the corresponding dinucleoside phosphates (dNpdNs) by treatment with alkali to permit subsequent 32p labeling. The resulting labeled dinucleotides (32pd-NpdN) are then analyzed by PAGE. Validation of this method has been carried out using a polydeoxythymidylic acid oligonucleotide containing a site-specific methyl PTE. The method has been applied to the in vitro analysis of calf thymus (CT) DNA treated with dimethylsulfate (DMS) or diethylsulfate (DES) and to the analysis of liver DNA from mice treated in vivo with nitrosodiethylamine. In each case, autoradiograms of the polyacrylamide gels showed the anticipated five bands representing the sixteen labeled dinucleotides, with proportional increases observed as the concentrations of DMS or DES used in the in vitro treatment of CT DNA were increased. The identity and frequency of the nucleosides located 5' to the PTE lesions were obtained by nuclease P1 digestion of the gel-isolated 32pdNpdN species and by analysis of the released labeled mononucleotides, 32pdN, by high-performance liquid chromatography with radioactivity detection. Results obtained from CT DNA treated with DMS or DES showed that the frequency of the four detected nucleotides reflected the normal

  10. Antibody mass escalation study in patients with castration resistant prostate cancer using 111I-J591: Lesion detectability and dosimetric projections for 90Y radioimmunotherapy

    PubMed Central

    Pandit-Taskar, Neeta; O’Donoghue, Joseph A.; Morris, Michael J; Wills, Eze A.; Schwartz, Lawrence H.; Gonen, Mithat; Scher, Howard I.; Larson, Steven M.; Divgi, Chaitanya R.

    2009-01-01

    Background J591, a monoclonal antibody that targets the external domain of the prostate specific membrane antigen (PSMA), has potential as an agent for radioimmunotherapy. A pilot trial was carried out in patients with prostate cancer using repetitive administrations of escalating masses of J591. An analysis was carried out to assess (1) lesion detectability by 111InJ591 gamma camera imaging compared to standard imaging methods and (2) the effect of increasing antibody mass on lesion detectability, biodistribution and dosimetry. Methods Fourteen patients with metastatic prostate cancer received escalating amounts (10, 25, 50 and 100 mg) of J591 in a series of administrations each separated by 3 weeks. All antibody administrations included a fixed amount of radiolabeled antibody 111In-DOTA-J591 (2mg of J591 labeled with 185MBq (5 mCi) of 111In via the chelating agent DOTA). Three whole body gamma camera scans with at least one SPECT scan together with multiple whole body count-rate measurements and serum activity concentration measurements were obtained in all patients. Images were analyzed for distribution and lesion targeting. Estimates of clearance rates and liver and lesion uptake were made for each treatment cycle. These estimates were used to generate dosimetric projections for radioimmunotherapy with 90Y-labeled J591. Results A total of 80 lesions in 14 patients were detected. Both skeletal and soft tissue disease was targeted by the antibody as seen on 111In-J591 scans. Antibody localized to 93.7% of skeletal lesions detected by conventional imaging. Clearance of radioactivity from whole body, serum and liver was dependent on antibody mass. Normalized average values of the ratio of residence times between lesion and liver for 10, 25, 50 and 100mg of antibody were 1.0, 1.9, 3.2 and 4.0 respectively. Dosimetric projections for radioimmunotherapy with 90Y-labeled J591 suggested similar absorbed doses to lesions, for treatment at the maximally tolerated activity

  11. Detection of Left Ventricular Regional Dysfunction and Myocardial Abnormalities Using Complementary Cardiac Magnetic Resonance Imaging in Patients with Systemic Sclerosis without Cardiac Symptoms: A Pilot Study.

    PubMed

    Kobayashi, Yasuyuki; Kobayashi, Hitomi; T Giles, Jon; Yokoe, Isamu; Hirano, Masaharu; Nakajima, Yasuo; Takei, Masami

    2016-01-01

    Objective We sought to detect the presence of left ventricular regional dysfunction and myocardial abnormalities in systemic sclerosis (SSc) patients without cardiac symptoms using a complementary cardiac magnetic resonance (CMR) imaging approach. Methods Consecutive patients with SSc without cardiac symptoms and healthy controls underwent CMR on a 1.5 T scanner. The peak systolic regional function in the circumferential and radial strain (Ecc, % and Err, %) were calculated using a feature tracking analysis on the mid-left ventricular slices obtained with cine MRI. In addition, we investigated the myocardial characteristics by contrast MRI. Pharmacological stress and rest perfusion scans were performed to assess perfusion defect (PD) due to micro- or macrovascular impairment, and late gadolinium enhancement (LGE) images were obtained for the assessment of myocarditis and/or fibrosis. Results We compared 15 SSc patients with 10 healthy controls. No statistically significant differences were observed in the baseline characteristics between the patients and healthy controls. The mean peak Err and Ecc of all segments was significantly lower in the patients than the controls (p=0.011 and p=0.003, respectively). Four patients with LGE (28.6%) and seven patients with PD (50.0%) were observed. PD was significantly associated with digital ulcers (p=0.005). Utilizing a linear regression model, the presence of myocardial LGE was significantly associated with the peak Ecc (p=0.024). After adjusting for age, the association between myocardial LGE and the peak Ecc was strengthened. Conclusion A subclinical myocardial involvement, as detected by CMR, was prevalent in the SSc patients without cardiac symptoms. Regional dysfunction might predict the myocardial abnormalities observed in SSc patients without cardiac symptoms.

  12. Cognitive impairment in multiple sclerosis.

    PubMed

    Jongen, P J; Ter Horst, A T; Brands, A M

    2012-04-01

    Cognitive impairment occurs in 40-65% of multiple sclerosis (MS) patients, typically involving complex attention, information processing speed, (episodic) memory and executive functions. It is seen in the subclinical radiologically isolated syndrome, clinically isolated syndrome, and all phases of clinical MS. In pediatric-onset MS cognition is frequently impaired and worsens relatively rapidly. Cognitive impairment often affects personal life and vocational status. Depression, anxiety and fatigue aggravate symptoms, whereas cognitive reserve partially protects. Cognitive dysfunction correlates to brain magnetic resonance imaging (MRI) lesion volumes and (regional) atrophy, and degree of and increase in MRI abnormalities predict further worsening. Experimental MRI indicates a crucial role for (focal) cortical lesions and atrophy, abnormal cortical integrity, and early changes in normal appearing brain tissue. Functional MRI suggests compensatory reorganization and adaptation changes in neural activities. Screening tools are the Brief Repeatable Neuropsychological Battery, Symbol Digit Modalities Test and Audio Recorded Cognitive Screen. The Minimal Assessment of Cognitive Function in Multiple Sclerosis (MS) is used for formal neuropsychological evaluation. What constitutes a clinically relevant change and how to optimally monitor cognition are issues to be settled. In relapsing-remitting MS timely and adequate disease modifying drug treatment may stabilize or possibly improve cognition. There is no evidence-based symptomatic drug treatment, nor are there optimal non-pharmacological approaches. Leisure activities enhance cognitive reserve. Cognitive rehabilitation in MS patients is still in its infancy. Cognitive behavioral therapy, exercise, and education programs are promising psychosocial interventions to improve coping and lessen cognitive symptoms.

  13. Trimodal color-fluorescence-polarization endoscopy aided by a tumor selective molecular probe accurately detects flat lesions in colitis-associated cancer

    PubMed Central

    Charanya, Tauseef; York, Timothy; Bloch, Sharon; Sudlow, Gail; Liang, Kexian; Garcia, Missael; Akers, Walter J.; Rubin, Deborah; Gruev, Viktor; Achilefu, Samuel

    2014-01-01

    Abstract. Colitis-associated cancer (CAC) arises from premalignant flat lesions of the colon, which are difficult to detect with current endoscopic screening approaches. We have developed a complementary fluorescence and polarization reporting strategy that combines the unique biochemical and physical properties of dysplasia and cancer for real-time detection of these lesions. Using azoxymethane-dextran sodium sulfate (AOM-DSS) treated mice, which recapitulates human CAC and dysplasia, we show that an octapeptide labeled with a near-infrared (NIR) fluorescent dye selectively identified all precancerous and cancerous lesions. A new thermoresponsive sol-gel formulation allowed topical application of the molecular probe during endoscopy. This method yielded high contrast-to-noise ratios (CNR) between adenomatous tumors (20.6±1.65) and flat lesions (12.1±1.03) and surrounding uninvolved colon tissue versus CNR of inflamed tissues (1.62±0.41). Incorporation of nanowire-filtered polarization imaging into NIR fluorescence endoscopy shows a high depolarization contrast in both adenomatous tumors and flat lesions in CAC, reflecting compromised structural integrity of these tissues. Together, the real-time polarization imaging provides real-time validation of suspicious colon tissue highlighted by molecular fluorescence endoscopy. PMID:25473883

  14. Trimodal color-fluorescence-polarization endoscopy aided by a tumor selective molecular probe accurately detects flat lesions in colitis-associated cancer

    NASA Astrophysics Data System (ADS)

    Charanya, Tauseef; York, Timothy; Bloch, Sharon; Sudlow, Gail; Liang, Kexian; Garcia, Missael; Akers, Walter J.; Rubin, Deborah; Gruev, Viktor; Achilefu, Samuel

    2014-12-01

    Colitis-associated cancer (CAC) arises from premalignant flat lesions of the colon, which are difficult to detect with current endoscopic screening approaches. We have developed a complementary fluorescence and polarization reporting strategy that combines the unique biochemical and physical properties of dysplasia and cancer for real-time detection of these lesions. Using azoxymethane-dextran sodium sulfate (AOM-DSS) treated mice, which recapitulates human CAC and dysplasia, we show that an octapeptide labeled with a near-infrared (NIR) fluorescent dye selectively identified all precancerous and cancerous lesions. A new thermoresponsive sol-gel formulation allowed topical application of the molecular probe during endoscopy. This method yielded high contrast-to-noise ratios (CNR) between adenomatous tumors (20.6±1.65) and flat lesions (12.1±1.03) and surrounding uninvolved colon tissue versus CNR of inflamed tissues (1.62±0.41). Incorporation of nanowire-filtered polarization imaging into NIR fluorescence endoscopy shows a high depolarization contrast in both adenomatous tumors and flat lesions in CAC, reflecting compromised structural integrity of these tissues. Together, the real-time polarization imaging provides real-time validation of suspicious colon tissue highlighted by molecular fluorescence endoscopy.

  15. A cross sectional study of renal involvement in tuberous sclerosis.

    PubMed Central

    Cook, J A; Oliver, K; Mueller, R F; Sampson, J

    1996-01-01

    Renal disease is a frequent manifestation of tuberous sclerosis (TSC) and yet little is known about its true prevalence or natural history. We reviewed the notes of 139 people with TSC, who had presented without renal symptoms, but who had been investigated by renal ultrasound. Information on the frequency, type, and symptomatology of renal involvement was retrieved. The prevalence of renal involvement was 61%. Angiomyolipomas were detected in 49%, renal cysts in 32%, and renal carcinoma in 2.2%. The prevalence of angiomyolipoma was positively correlated with age, compatible with a two hit aetiology. Renal cysts were the commoner lesion in young children, and their prevalence did not appear to be age related. Renal investigation in people with TSC had been inconsistent and limited. We suggest guidelines for renal investigation in those with TSC. Images PMID:8782048

  16. Genetics Home Reference: multiple sclerosis

    MedlinePlus

    ... Me Understand Genetics Home Health Conditions multiple sclerosis multiple sclerosis Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Multiple sclerosis is a condition characterized by areas of damage ( ...

  17. Pathogenesis of multiple sclerosis: insights from molecular and metabolic imaging.

    PubMed

    Ciccarelli, Olga; Barkhof, Frederik; Bodini, Benedetta; De Stefano, Nicola; Golay, Xavier; Nicolay, Klaas; Pelletier, Daniel; Pouwels, Petra J W; Smith, Seth A; Wheeler-Kingshott, Claudia A M; Stankoff, Bruno; Yousry, Tarek; Miller, David H

    2014-08-01

    The mechanisms underlying the pathogenesis of multiple sclerosis induce the changes that underpin relapse-associated and progressive disability. Disease mechanisms can be investigated in preclinical models and patients with multiple sclerosis by molecular and metabolic imaging techniques. Many insights have been gained from such imaging studies: persisting inflammation in the absence of a damaged blood-brain barrier, activated microglia within and beyond lesions, increased mitochondrial activity after acute lesions, raised sodium concentrations in the brain, increased glutamate in acute lesions and normal-appearing white matter, different degrees of demyelination in different patients and lesions, early neuronal damage in grey matter, and early astrocytic proliferation and activation in lesions and white matter. Clinical translation of molecular and metabolic imaging and extension of these techniques will enable the assessment of novel drugs targeted at these disease mechanisms, and have the potential to improve health outcomes through the stratification of patients for treatments.

  18. Eosinophilic Fasciitis: A Rare Skin Sclerosis

    PubMed Central

    Servy, Amandine; Clérici, Thierry; Malines, Caroline; Le Parc, Jean-Marie; Côté, Jean-François

    2011-01-01

    Eosinophilic fasciitis (Schulman's syndrome) is a rare disease with specific clinical symptoms such as the groove sign which facilitate diagnosis. We report a typical case of eosinophilic fasciitis in an otherwise healthy 49-year-old man who presented with “prayer and groove signs”. Histological analysis showed sclerosis and eosinophilic infiltration of the fascia. The patient was successfully treated with systemic corticotherapy and Cyclosporine. A short review of the clinicopathological features of the lesions is presented. PMID:21151540

  19. Ocular contrapulsion in multiple sclerosis: clinical features and pathophysiological mechanisms

    PubMed Central

    Frohman, E; Frohman, T; Fleckenstein, J; Racke, M; Hawker, K; Kramer, P

    2001-01-01

    The objective was to describe in multiple sclerosis, a cerebellar eye movement syndrome that resulted from an acute episode of inflammatory demyelination. Contrapulsion is an ocular motor disturbance characterised by a triad of (1) hypermetric saccadic eye movements in a direction opposite from a precisely localised lesion within a specific white matter pathway, the uncinate fasciculus, at the level of the superior cerebellar peduncle (SCP); (2) hypometric saccades towards the side of the lesion; (3) oblique saccades directed away from the side of the lesion on attempted vertical saccades.
 Infrared oculography was used to demonstrate the characteristic features of contrapulsion in two patients with multiple sclerosis.
 Brain MRI showed lesions within the region of the uncinate fasciculus and superior cerebellar peduncle in both patients. Eye movement recordings showed saccadic hypermetria away from the side of the lesion and saccadic hypometria towards the side of the lesion. The hypometria decomposed into a series of stepwise movements as the eye approached the target. Oblique saccades directed away from the side of the lesion were seen on attempted vertical saccades.
In conclusion, ocular contrapulsion can be seen in patients with multiple sclerosis and results from a lesion in the region of the SCP, involving the uncinate fasciculus.

 PMID:11309470

  20. Analysis of Non-Small Bowel Lesions Detected by Capsule Endoscopy in Patients with Potential Small Bowel Bleeding

    PubMed Central

    Akin, Fatma Ebru; Yurekli, Oyku Tayfur; Demirezer Bolat, Aylin; Tahtacı, Mustafa; Koseoglu, Huseyin; Selvi, Eyup; Buyukasik, Naciye Semnur; Ersoy, Osman

    2016-01-01

    Gastrointestinal (GI) bleeding cases in whom source cannot be identified after conventional upper and lower GI endoscopy are defined as potential small bowel bleeding. We aimed to search for lesions in the reach of conventional endoscopy in patients to whom video capsule endoscopy (VCE) had been applied for potential small bowel bleeding. 114 patients who had VCE evaluation for potential small bowel bleeding between January 2009 and August 2015 were retrospectively evaluated. Mean age of the patients was 55 ± 17 years. Female/male ratio is 39/75. In 58 patients (50.9%) bleeding lesion could be determined. Among these 58 patients 8 patients' lesions were in the reach of conventional endoscopes. Overall these 8 patients comprised 7% of patients in whom VCE was performed for potential small bowel bleeding. Among these 8 patients 5 had colonic lesions (4 angiodysplasia, 1 ulcerated polypoid cecal lesion), 2 had gastric lesions (1 GAVE, 1 anastomotic bleeding), and 1 patient had a bleeding lesion in the duodenal bulbus. Although capsule endoscopy is usually performed for potential small bowel bleeding gastroenterologists should always keep in mind that these patients may be suffering from bleeding from non-small bowel segments and should carefully review images captured from non-small bowel areas. PMID:27092029

  1. Differentiation of Malignant and Benign Incidental Breast Lesions Detected by Chest Multidetector-Row Computed Tomography: Added Value of Quantitative Enhancement Analysis

    PubMed Central

    Lin, Yu-Pang; Hsu, Hsian-He; Ko, Kai-Hsiung; Chu, Chi-Ming; Chou, Yu-Ching; Chang, Wei-Chou; Chang, Tsun-Hou

    2016-01-01

    To retrospectively determine the association between breast lesion morphology and malignancy and to determine the optimal value of lesion enhancement (HU, Hounsfield units) to improve the diagnostic accuracy of breast cancer in patients with incidental breast lesions (IBLs). A total of 97 patients with 102 IBLs detected from July 2009 to December 2012 were enrolled in this study. Two radiologists analyzed CT images for the presence of malignancy based on the morphology of the lesions alone and in combination with an enhancement value (HU) analysis. There were 36 malignant and 66 benign IBLs. When the morphology and enhancement values were combined, the sensitivity, specificity, and accuracy were 92%, 97%, and 95%, respectively, for reader 1 and 89%, 94%, and 92%, respectively, for reader 2. The addition of HU values led to correct changes in the diagnosis; specifically, the accuracy of the diagnosis of reader 1 and reader 2 improved by 6.9% and 11.8%, respectively. The addition of the enhancement value (HU) to the CT morphology improved the diagnostic accuracy in the differentiation of malignant from benign IBLs by using the region of interest (ROI) to measure the HU within the most suspicious part of the lesion. PMID:27128524

  2. Papanicolau smear chances to be diagnostic for cervical squamous intraepithelial lesions (SIL) with or without detectable HPV DNA at in situ hybridization analysis.

    PubMed

    Sopracordevole, F; Cadorin, L; Muffato, G; De Benetti, L; Parin, A

    1993-01-01

    The Authors have correlated 39 cervical diagnostic biopsies for squamous intraepithelial lesions (SILs) with correspective Papanicolau smears (PS), with relation to the presence or the absence of HPV of oncogenic type (HPV-one) detected by in situ hybridization (ISH). Agreement between cytological and histological diagnosis was present in 14 of 16 cases with detectable HPV-one and only in 12 of 23 cases without detectable HPV-one at ISH. The importance of the HPV type in the SILs with relation to the diagnostic accuracy of Papanicolaou smears has been discussed.

  3. Characteristics, detection methods, and treatment of questionable occlusal carious lesions: findings from The National Dental Practice-Based Research Network

    PubMed Central

    Makhija, Sonia K; Gilbert, Gregg H.; Funkhouser, Ellen; Bader, James D; Gordan, Valeria V.; Rindal, D. Brad; Pihlstrom, Daniel J.; Qvist, Vibeke

    2014-01-01

    Questionable occlusal carious lesions (QOC) can be defined as an occlusal tooth surface with no cavitation and no radiographic radiolucencies, but caries is suspected due to roughness, surface opacities, or staining. An earlier analysis of data from this study indicates ⅓ of patients have a QOC. The objective of this report is to quantify the characteristics of these common lesions, diagnostic aids used, and treatment of QOC. A total of 82 dentist and hygienist practitioner-investigators from the United States and Denmark in The National Dental Practice-Based Research Network participated. When consented patients presented with a QOC, information was recorded about the patient, tooth, lesion, and treatments. 2,603 QOC from 1,732 patients were analyzed. Lesions were usually associated with a fissure, on molars, and varied from yellow to black in color. Half presented with a chalky luster and had a rough surface when examined with an explorer. There was an association between color and luster, 10% were chalky-light, 47% were shiny-dark, and 42% were mixtures. A higher proportion of chalky than shiny lesions were light (22% vs. 9%; p < 0.001). Lesions light in color were less common in adults than pediatric patients (9% vs. 32%; p < 0.001). Lesions that were chalky and light were more common among pediatric than adult patients (22% vs. 6%, p < 0.001). This is the first study to investigate characteristics of QOC in routine clinical practice. Clinicians commonly face this diagnostic uncertainty. Determining the characteristics of these lesions are relevant when making diagnostic and treatment decisions. PMID:24480989

  4. Characteristics, detection methods and treatment of questionable occlusal carious lesions: findings from the national dental practice-based research network.

    PubMed

    Makhija, S K; Gilbert, G H; Funkhouser, E; Bader, J D; Gordan, V V; Rindal, D B; Pihlstrom, D J; Qvist, V

    2014-01-01

    Questionable occlusal carious lesions (QOC) can be defined as an occlusal tooth surface with no cavitation and no radiographic radiolucencies, but caries is suspected due to roughness, surface opacities or staining. An earlier analysis of data from this study indicates 1/3 of patients have a QOC. The objective of this report has been to quantify the characteristics of these common lesions, the diagnostic aids used and the treatment of QOC. A total of 82 dentist and hygienist practitioner-investigators from the USA and Denmark in the National Dental Practice-Based Research Network participated. When consenting patients presented with a QOC, information was recorded about the patient, tooth, lesion and treatments. A total of 2,603 QOC from 1,732 patients were analyzed. The lesions were usually associated with a fissure, on molars, and varied from yellow to black in color. Half presented with a chalky luster and had a rough surface when examined with an explorer. There was an association between color and luster: 10% were chalky-light, 47% were shiny-dark and 42% were mixtures. A higher proportion of chalky than of shiny lesions were light (22 vs. 9%; p < 0.001). Lesions light in color were less common in adults than in pediatric patients (9 vs. 32%; p < 0.001). Lesions that were chalky and light were more common among pediatric than among adult patients (22 vs. 6%; p < 0.001). This is the first study to investigate characteristics of QOC in routine clinical practice. Clinicians commonly face this diagnostic uncertainty. Determining the characteristics of these lesions is relevant when making diagnostic and treatment decisions. PMID:24480989

  5. MS lesion segmentation using a multi-channel patch-based approach with spatial consistency

    NASA Astrophysics Data System (ADS)

    Mechrez, Roey; Goldberger, Jacob; Greenspan, Hayit

    2015-03-01

    This paper presents an automatic method for segmentation of Multiple Sclerosis (MS) in Magnetic Resonance Images (MRI) of the brain. The approach is based on similarities between multi-channel patches (T1, T2 and FLAIR). An MS lesion patch database is built using training images for which the label maps are known. For each patch in the testing image, k similar patches are retrieved from the database. The matching labels for these k patches are then combined to produce an initial segmentation map for the test case. Finally a novel iterative patch-based label refinement process based on the initial segmentation map is performed to ensure spatial consistency of the detected lesions. A leave-one-out evaluation is done for each testing image in the MS lesion segmentation challenge of MICCAI 2008. Results are shown to compete with the state-of-the-art methods on the MICCAI 2008 challenge.

  6. Renal manifestations of tuberous sclerosis complex.

    PubMed

    O'Hagan, A R; Ellsworth, R; Secic, M; Rothner, A D; Brouhard, B H

    1996-10-01

    Patients with tuberous sclerosis complex (TSC) are at increased risk of renal disease, predominantly angiomyolipomas and renal cysts. We retrospectively reviewed clinical data of 71 patients diagnosed with TSC. Progression of renal lesions was noted. TSC patients with renal lesions were compared with TSC patients without renal disease. Fifteen of 38 patients had renal abnormalities by imaging at presentation. Six of 9 with initially normal kidneys subsequently developed new lesions. Although not of statistical significance, there was a trend toward increased retinal hamartomas, cardiac rhabdomyomas, and skin lesions in those patients who also had renal abnormalities. Renal disease should be considered and sought in all patients with TSC, both at initial presentation and subsequently, since renal disease is a very significant cause of morbidity and mortality.

  7. Computer-Aided Decision Support for Melanoma Detection Applied on Melanocytic and Nonmelanocytic Skin Lesions: A Comparison of Two Systems Based on Automatic Analysis of Dermoscopic Images

    PubMed Central

    Møllersen, Kajsa; Kirchesch, Herbert; Zortea, Maciel; Schopf, Thomas R.; Hindberg, Kristian; Godtliebsen, Fred

    2015-01-01

    Commercially available clinical decision support systems (CDSSs) for skin cancer have been designed for the detection of melanoma only. Correct use of the systems requires expert knowledge, hampering their utility for nonexperts. Furthermore, there are no systems to detect other common skin cancer types, that is, nonmelanoma skin cancer (NMSC). As early diagnosis of skin cancer is essential, there is a need for a CDSS that is applicable to all types of skin lesions and is suitable for nonexperts. Nevus Doctor (ND) is a CDSS being developed by the authors. We here investigate ND's ability to detect both melanoma and NMSC and the opportunities for improvement. An independent test set of dermoscopic images of 870 skin lesions, including 44 melanomas and 101 NMSCs, were analysed by ND. Its sensitivity to melanoma and NMSC was compared to that of Mole Expert (ME), a commercially available CDSS, using the same set of lesions. ND and ME had similar sensitivity to melanoma. For ND at 95% melanoma sensitivity, the NMSC sensitivity was 100%, and the specificity was 12%. The melanomas misclassified by ND at 95% sensitivity were correctly classified by ME, and vice versa. ND is able to detect NMSC without sacrificing melanoma sensitivity. PMID:26693486

  8. Improving the performance of lesion-based computer-aided detection schemes of breast masses using a case-based adaptive cueing method

    NASA Astrophysics Data System (ADS)

    Tan, Maxine; Aghaei, Faranak; Wang, Yunzhi; Qian, Wei; Zheng, Bin

    2016-03-01

    Current commercialized CAD schemes have high false-positive (FP) detection rates and also have high correlations in positive lesion detection with radiologists. Thus, we recently investigated a new approach to improve the efficacy of applying CAD to assist radiologists in reading and interpreting screening mammograms. Namely, we developed a new global feature based CAD approach/scheme that can cue the warning sign on the cases with high risk of being positive. In this study, we investigate the possibility of fusing global feature or case-based scores with the local or lesion-based CAD scores using an adaptive cueing method. We hypothesize that the information from the global feature extraction (features extracted from the whole breast regions) are different from and can provide supplementary information to the locally-extracted features (computed from the segmented lesion regions only). On a large and diverse full-field digital mammography (FFDM) testing dataset with 785 cases (347 negative and 438 cancer cases with masses only), we ran our lesion-based and case-based CAD schemes "as is" on the whole dataset. To assess the supplementary information provided by the global features, we used an adaptive cueing method to adaptively adjust the original CAD-generated detection scores (Sorg) of a detected suspicious mass region based on the computed case-based score (Scase) of the case associated with this detected region. Using the adaptive cueing method, better sensitivity results were obtained at lower FP rates (<= 1 FP per image). Namely, increases of sensitivities (in the FROC curves) of up to 6.7% and 8.2% were obtained for the ROI and Case-based results, respectively.

  9. Computer-aided tracking of MS lesions

    NASA Astrophysics Data System (ADS)

    Sturm, Deborah; Gurwitz Kletenik, Devorah; Koshy, Philip

    2011-03-01

    Multiple Sclerosis (MS) lesions are known to change over time. The location, size and shape characteristics of lesions are often used to diagnose and to track disease progression. We have improved our lesion-browsing tool that allows users to automatically locate successive significant lesions in a MRI stack. In addition, an automatic alignment feature was implemented to facilitate comparisons across stacks. A lesion stack is formed that can be browsed independently or in tandem with the image windows. Lesions of interest can then be measured, rendered and rotated. Multiple windows allow the viewer to compare the size and shape of lesions from the MRI images of the same patient taken at different time intervals.

  10. Limited heterogeneity of rearranged T-cell receptor Vα transcripts in brains of multiple sclerosis patients

    NASA Astrophysics Data System (ADS)

    Oksenberg, Jorge R.; Stuart, Simon; Begovich, Ann B.; Bell, Robert B.; Erlich, Henry A.; Steinman, Lawrence; Bernard, Claude C. A.

    1990-05-01

    THE identification of activated ? cells in the brain of individuals with multiple sclerosis (MS) indicates that these cells are critical in the pathogenesis of this disease. In an attempt to elucidate the nature of the lymphocytic infiltration, we used the polymerase chain reaction to amplify T-cell antigen receptor (TCR) Vα sequences from transcripts derived from MS brain lesions. In each of three MS brains, only two to four rearranged TCR Vα transcripts were detected. No Vα transcripts could be found in control brains. Sequence analysis of transcripts encoded by the Vα 12.1 region showed rearrangements to a limited number of Jα region segments. These results imply that TCR Vα gene expression in MS brain lesions is restricted.

  11. Multiple sclerosis: the disease and its manifestations.

    PubMed Central

    McDonald, W I; Ron, M A

    1999-01-01

    Multiple sclerosis is an immune-mediated inflammatory demyelinating disease of the central nervous system clinically characterized by relapses and remissions of neurological disturbance. A typical relapse, exemplified by optic neuritis, increases in severity over a week or two and after approximately one month begins to remit. Resolution takes place over the course of two to three months. In the early stages, clinical recovery is virtually complete, though persistent abnormalities of conduction can usually be detected by evoked potential techniques and persistent structural abnormalities can be detected by magnetic resonance imaging (MRI). These techniques, together with cerebrospinal fluid examination for oligoclonal IgG, provide supporting evidence for the diagnosis which, in the absence of a specific test, nevertheless remains primarily clinical. The course of the disease is very variable, but after a number of years neurological deficit begins to accumulate after each relapse. In most patients, the relapsing and remitting phase of the disease is followed by a phase of continuous progression of disability. Cognitive disturbances can be detected in many patients even quite early in the course of the illness. Deficits in attention, memory and executive skills may be prominent and tend to become increasingly prominent as neurological deficit increases, although this is not always the case. There is some correlation between the extent of MRI abnormalities in the cerebral white matter and the severity of cognitive deficit. Depression and anxiety are commonly experienced but are poorly correlated to the lesion load seen on MRI. In contrast, the much rarer psychotic symptoms, euphoria and emotional lability are closely linked to the severity of white matter disease. PMID:10603614

  12. Perirhinal cortex lesions uncover subsidiary systems in the rat for the detection of novel and familiar objects

    PubMed Central

    Albasser, Mathieu M; Amin, Eman; Iordanova, Mihaela D; Brown, Malcolm W; Pearce, John M; Aggleton, John P

    2011-01-01

    The present study compared the impact of perirhinal cortex lesions on tests of object recognition. Object recognition was tested directly by looking at the preferential exploration of novel objects over simultaneously presented familiar objects. Object recognition was also tested indirectly by presenting just novel objects or just familiar objects, and recording exploration levels. Rats with perirhinal cortex lesions were severely impaired at discriminating a novel object from a simultaneously presented familiar object (direct test), yet displayed normal levels of exploration to novel objects presented on their own and showed normal declines in exploration times for familiar objects that were repeatedly presented (indirect tests). This effective reduction in the exploration of familiar objects after perirhinal cortex lesions points to the sparing of some recognition mechanisms. This possibility led us to determine whether rats with perirhinal cortex lesions can overcome their preferential exploration deficits when given multiple object familiarisation trials prior to that same (familiar) object being paired with a novel object. It was found that after multiple familiarisation trials, objects could now successfully be recognised as familiar by rats with perirhinal cortex lesions, both following a 90-min delay (the longest delay tested) and when object recognition was tested in the dark after familiarisation trials in the light. These latter findings reveal: (i) the presumed recruitment of other regions to solve recognition memory problems in the absence of perirhinal cortex tissue; and (ii) that these additional recognition mechanisms require more familiarisation trials than perirhinal-based recognition mechanisms. PMID:21707792

  13. Early detection of lesions of dorsal artery of foot in patients with type 2 diabetes mellitus by high-frequency ultrasonography.

    PubMed

    Zhang, Yanrong; Li, Wenjing; Yan, Tianwei; Lu, Chengfa; Zhou, Xiang; Huang, Yan

    2009-06-01

    This study evaluated the value of high-frequency ultrasonograpy for early detection of dorsal artery of foot in patients with type 2 diabetes mellitus (MD). Eighty subjects including 40 patients with type 2 MD (T2DM group) and 40 healthy volunteers (NC group) were recruited. The intima-media thickness (IMT), the inner diameter and the perfusion of dorsal artery of foot were measured by using high-frequency ultrasonograpy. Meanwhile, the parameters of vascular elasticity, including stiffness parameter (beta), pressure-strain elastic modulus (Erho), arterial compliance (AC), augment index (AI), and pulse wave conducting velocity (PWVbeta) were detected by means of echo-tracking technique. The results showed that no significant difference was found in the IMT, systolic diameter (Ds), diastolic diameter (Dd) and peak systolic velocity (PSV) between T2DM and NC groups. Erho and PWVbeta were increased, and AC was decreased in T2DM group as compared with those in NC group with the differences being significant (P<0.05 for all). There was no significant difference in beta and AI between T2DM and NC groups. It was concluded that high-frequency ultrasonography in combination with echo-tracking technique is sensitive and non-invasive, and can be used for early detection of sclerosis of the lower extremity artery in patients with type 2 MD.

  14. Taste dysfunction in multiple sclerosis.

    PubMed

    Doty, Richard L; Tourbier, Isabelle A; Pham, Dzung L; Cuzzocreo, Jennifer L; Udupa, Jayaram K; Karacali, Bilge; Beals, Evan; Fabius, Laura; Leon-Sarmiento, Fidias E; Moonis, Gul; Kim, Taehoon; Mihama, Toru; Geckle, Rena J; Yousem, David M

    2016-04-01

    Empirical studies of taste function in multiple sclerosis (MS) are rare. Moreover, a detailed assessment of whether quantitative measures of taste function correlate with the punctate and patchy myelin-related lesions found throughout the CNS of MS patients has not been made. We administered a 96-trial test of sweet (sucrose), sour (citric acid), bitter (caffeine) and salty (NaCl) taste perception to the left and right anterior (CN VII) and posterior (CN IX) tongue regions of 73 MS patients and 73 matched controls. The number and volume of lesions were assessed using quantitative MRI in 52 brain regions of 63 of the MS patients. Taste identification scores were significantly lower in the MS patients for sucrose (p = 0.0002), citric acid (p = 0.0001), caffeine (p = 0.0372) and NaCl (p = 0.0004) and were present in both anterior and posterior tongue regions. The percent of MS patients with identification scores falling below the 5th percentile of controls was 15.07 % for caffeine, 21.9 % for citric acid, 24.66 % for sucrose, and 31.50 % for NaCl. Such scores were inversely correlated with lesion volumes in the temporal, medial frontal, and superior frontal lobes, and with the number of lesions in the left and right superior frontal lobes, right anterior cingulate gyrus, and left parietal operculum. Regardless of the subject group, women outperformed men on the taste measures. These findings indicate that a sizable number of MS patients exhibit taste deficits that are associated with MS-related lesions throughout the brain. PMID:26810729

  15. Optical detection of cancer and precancerous lesions of the upper aerodigestive tract: methods for assessment of vertical extensions

    NASA Astrophysics Data System (ADS)

    Kraft, Marcel; Arens, Christoph

    2013-06-01

    Introduction: Endoscopic imaging can be used in the assessment of cancer and precancerous lesions of the upper aerodigestive tract. The objective of this presentation is to describe vertical imaging methods. Methods: The working principle and technique of optical coherence tomography (OCT) as well as endosonography (EUS) are briefly illustrated. Results: The main indications, normal and pathologic findings of each method, frequent pitfalls, and clinical results up to now are presented in detail. Conclusions: Endosonography helps in determining the exact extension of advanced carcinomas beyond 3 mm, while OCT, due to its better resolution, is superior in the assessment of precancerous and early cancerous lesions up to 2 mm thickness.

  16. Can imaging techniques measure neuroprotection and remyelination in multiple sclerosis?

    PubMed

    Zivadinov, Robert

    2007-05-29

    MRI is the most important paraclinical measure for assessing and monitoring the pathologic changes implicated in the onset and progression of multiple sclerosis (MS). Conventional MRI sequences, such as T1-weighted gadolinium-enhanced and spin-echo T2-weighted imaging, are unable to provide full details about the degree of inflammation and underlying neurodegenerative changes. Newer nonconventional MRI techniques have the potential to detect clinical impairment, disease progression, accumulation of disability, and the neuroprotective effects of treatment. Unenhanced T1-weighted imaging can reveal hypointense black holes, a measure of chronic neurodegeneration. Two- and three-dimensional fluid-attenuated inversion recovery sequences allow better identification of cortical lesions. Ultrahigh-field strength MRI has the potential to detect subpial cortical and deep gray matter lesions. Magnetization transfer imaging is increasingly used to characterize the evolution of MS lesions and normal-appearing brain tissue. Evidence suggests that the dynamics of magnetization transfer changes correlate with the extent of demyelination and remyelination. Magnetic resonance spectroscopy, which provides details on tissue biochemistry, metabolism, and function, also has the capacity to reveal neuroprotective mechanisms. By measuring the motion of water, diffusion imaging can provide information about the orientation, size, and geometry of tissue damage in white and gray matter. Functional MRI may help clarify the brain's plasticity-dependent compensatory mechanisms in patients with MS. High-resolution microautoradiography and new contrast agents are proving to be sensitive means for characterizing molecular markers of disease activity, such as activated microglia and macrophages. Optical coherence tomography, a new research technique, makes it possible to investigate relevant physiologic systems that provide accurate measures of tissue changes secondary to the MS disease process

  17. Peripheral-type benzodiazepine receptor binding 4{prime}-IODO-PK11195: A new radioiodinated ligand for detecting lesioned brain areas

    SciTech Connect

    Saji, H.; Iida, Y.; Nakatsuka, I.

    1995-05-01

    An increase in the peripheral-type benzodiazepine binding sites (PBBS) has recently been reported in excitotoxic and ischaemic lesions in the brain. Thus, PBBS visualization has been of greater interest due to the possibility of imaging the lesioned area as positive image. In this study, our interest is focussed in the development of a radioiodinated compound for the SPECT study of PBBS function. Taking account of the environment of binding sites and the stability in vivo, we selected the 4{prime}position of C-1 phenyl moiety of the isoqunoline derivative PK11195 as the best exploitable site for the iodination. The no-carrier-added I-125 labeled 4{prime}-iodo-PK11195 (IPK) was synthesized by the bromine-iodine exchange reaction in 60% radiochemical yield and > 98% radiochemical purity. In vitro competitive binding studies with H-3-PI11195 using rat kidney membranes shows that IPK has high affinity for PBBS as much as PK11195. The in vivo biodistribution in mice showed high uptake of I-125-IPK in the kidney, lung, heart and adrenal, organs reported as containing high PBBS, which were reduced by the treatment with cold PK11195. Furthermore, autoradiographic studies in transient middle cerebral arteries occlusion in rats showed high accumulation of I-125-IPK in lesioned sites, in contrast to the decease of radioactivity of Tc-99m-HM-PAO. Gathered data indicated that the newly designed IPK holds to great potential for detecting the lesioned brain areas as positive image.

  18. Brain-stem involvement in multiple sclerosis: a comparison between brain-stem auditory evoked potentials and the acoustic stapedius reflex.

    PubMed

    Kofler, B; Oberascher, G; Pommer, B

    1984-01-01

    Brain-stem auditory evoked potentials (BAEPs) and the acoustic stapedius reflex (ASR) were recorded in 68 patients with definite, probable and possible multiple sclerosis (using the definitions of McAlpine). The high incidence of abnormal results, 68% and 60%, respectively, pointed to the diagnostic value of these two measures in detecting brain-stem dysfunction. Combination of the methods increased the diagnostic yield to 85%. Since in part the same brain-stem generator sites underlie BAEPs and the ASR, it was considered that a study of their correlation might serve to increase the reliability and validity of these techniques. There was 71% agreement overall between results from the two measures. Furthermore, 72% of the joint BAEP and ASR abnormalities corresponded in detection of the brain-stem lesion site. It was concluded that the combined approach may supply powerful, complementary information on brain-stem dysfunction, which may aid in establishing the diagnosis of multiple sclerosis.

  19. Audiovestibular involvement in systemic sclerosis.

    PubMed

    Berrettini, S; Ferri, C; Pitaro, N; Bruschini, P; Latorraca, A; Sellari-Franceschini, S; Segnini, G

    1994-01-01

    In order to evaluate the nature and association of audiovestibular disturbances and systemic sclerosis (SSC), 37 unselected SSC patients were studied with a detailed audiological and vestibular examination since November, 1987. Pure-tone audiometry, speech audiometry, impedance audiometry, brainstem response audiometry and vestibular function using electronystagmographic recording were performed. We found a rather frequent audiovestibular involvement (41%). A hearing loss was found in 14 SSC patients; hearing loss was sensorineural in 10 cases and mixed in 4 cases. The latter revealed a finding similar to tympanosclerosis. Four patients showed altered vestibular test values and only one of these had normal hearing. Sensorineural deafness was the more frequent pathological finding and in all cases the site of lesion was cochlear. SSC appears to be directly responsible for audiovestibular damage, since in 12 out of 15 patients with such involvement, no other apparent cause could be revealed. SSC may be included among the autoimmune diseases which may cause audiovestibular disturbances. PMID:8078672

  20. Hughes syndrome and multiple sclerosis.

    PubMed

    Uthman, I; Noureldine, M H A; Berjawi, A; Skaf, M; Haydar, A A; Merashli, M; Hughes, G R V

    2015-02-01

    Multiple sclerosis (MS) and antiphospholipid syndrome (APS) share common clinical, laboratory and radiological features. We reviewed all the English papers on MS and APS published in the literature from 1965 to 2014 using PubMed and Google Scholar. We found that APS can mimic antiphospholipid antibodies (aPL)-positive MS in many ways in its clinical presentation. Nevertheless, APS diagnosis, clinical manifestations and management differ from those of MS. aPL were found in MS patients with titers ranging from 2% to 88%. The distribution and volume of lesions on magnetic resonance imaging (MRI) may help to differentiate MS from primary APS. In addition, atypical MS presentation can guide physicians toward an alternative diagnosis, especially when features of thrombosis and/or history of connective tissue disease are present. In that case, an anticoagulation trial could be worthwhile. PMID:25326228

  1. Magnetic resonance imaging of liver lesions: exceptions and atypical lesions.

    PubMed

    van den Bos, Indra C; Hussain, Shahid M; de Man, Robert A; Zondervan, Pieter E; Ijzermans, Jan N M; Preda, A; Krestin, Gabriel P

    2008-01-01

    On state-of-the-art magnetic resonance imaging, most lesions can be detected and characterized with confidence according to well-known criteria. However, atypical characteristics in some common lesions and the incidental encounter with rare lesions may pose diagnostic difficulties. In this article, six challenging hepatic lesions will be discussed and evaluated on the most important magnetic resonance imaging sequences, with histological correlation when available. In addition, the background information concerning these lesions will be described based on the most recent available literature. By reading this article, the reader will be able to (1) categorize the lesion in solid and fluid-containing lesions, based on the T2 signal intensity; and (2) define the benign or malignant nature of the lesion, in relation to the signal intensity and dynamic enhancement pattern, despite the presence of atypical characteristics of some lesions. PMID:18436109

  2. Performance assessment of HIFU lesion detection by harmonic motion imaging for focused ultrasound (HMIFU): a 3-D finite-element-based framework with experimental validation.

    PubMed

    Hou, Gary Y; Luo, Jianwen; Marquet, Fabrice; Maleke, Caroline; Vappou, Jonathan; Konofagou, Elisa E

    2011-12-01

    Harmonic motion imaging for focused ultrasound (HMIFU) is a novel high-intensity focused ultrasound (HIFU) therapy monitoring method with feasibilities demonstrated in vitro, ex vivo and in vivo. Its principle is based on amplitude-modulated (AM) - harmonic motion imaging (HMI), an oscillatory radiation force used for imaging the tissue mechanical response during thermal ablation. In this study, a theoretical framework of HMIFU is presented, comprising a customized nonlinear wave propagation model, a finite-element (FE) analysis module and an image-formation model. The objective of this study is to develop such a framework to (1) assess the fundamental performance of HMIFU in detecting HIFU lesions based on the change in tissue apparent elasticity, i.e., the increasing Young's modulus, and the HIFU lesion size with respect to the HIFU exposure time and (2) validate the simulation findings ex vivo. The same HMI and HMIFU parameters as in the experimental studies were used, i.e., 4.5-MHz HIFU frequency and 25 Hz AM frequency. For a lesion-to-background Young's modulus ratio of 3, 6 and 9, the FE and estimated HMI displacement ratios were equal to 1.83, 3.69 and 5.39 and 1.65, 3.19 and 4.59, respectively. In experiments, the HMI displacement followed a similar increasing trend of 1.19, 1.28 and 1.78 at 10-s, 20-s and 30-s HIFU exposure, respectively. In addition, moderate agreement in lesion size growth was found in both simulations (16.2, 73.1 and 334.7 mm(2)) and experiments (26.2, 94.2 and 206.2 mm(2)). Therefore, the feasibility of HMIFU for HIFU lesion detection based on the underlying tissue elasticity changes was verified through the developed theoretical framework, i.e., validation of the fundamental performance of the HMIFU system for lesion detection, localization and quantification, was demonstrated both theoretically and ex vivo.

  3. (99m)Tc-DMSA (V) in Evaluation of Osteosarcoma: Comparative Studies with (18)F-FDG PET/CT in Detection of Primary and Malignant Lesions.

    PubMed

    Bandopadhyaya, G P; Gupta, Priyanka; Singh, Archana; Shukla, Jaya; Rastogi, S; Kumar, Rakesh; Malhotra, Arun

    2012-01-01

    To evaluate the role of (99m)Tc-DMSA (V) and [(18)F]FDG PET-CT in management of patients with osteosarcoma, 22 patients were included in our study. All patients underwent both (99m)Tc-DMSA (V) and whole-body [(18)F]FDG PET-CT scans within an interval of 1 week. 555-740 MBq of (99m)Tc-DMSA (V) was injected i.v. the whole-body planar, SPECT images of primary site and chest were performed after 3-4 hours. [(18)F]FDG PET-CT images were obtained 60 minutes after i.v. injection of 370 MBq of F-18 FDG. Both FDG PET-CT (mean SUV(max) = 7.1) and DMSA (V) scans showed abnormal uptake at primary site in all the 22 patients (100% sensitivity for both). Whole-body PET-CT detected metastasis in 11 pts (lung mets in 10 and lung + bone mets in 1 patient). Whole-body planar DMSA (V) and SPECT detected bone metastasis in one patient, lung mets in 7 patients and LN in 1 patient. HRCT of chest confirmed lung mets in 10 patients and inflammatory lesion in one patient. 7 patients positive for mets on DMSA (V) scan had higher uptake in lung lesions as compared to FDG uptake on PET-CT. Three patients who did not show any DMSA uptake had subcentimeter lung nodule. Resuts of both (99m)Tc-DMSA (V) (whole-body planar and SPECT imaging) and [(18)F]FDG PET-CT were comparable in evaluation of primary site lesions and metastatic lesions greater than 1 cm. Though (99m)Tc-DMSA (V) had higher uptake in the lesions as compared to [(18)F]FDG PET-CT, the only advantage [(18)F]FDG PET-CT had was that it could also detect subcentimeter lesions.

  4. [Managing focal incidental renal lesions].

    PubMed

    Nicolau, C; Paño, B; Sebastià, C

    2016-01-01

    Incidental renal lesions are relatively common in daily radiological practice. It is important to know the different diagnostic possibilities for incidentally detected lesions, depending on whether they are cystic or solid. The management of cystic lesions is guided by the Bosniak classification. In solid lesions, the goal is to differentiate between renal cancer and benign tumors such as fat-poor angiomyolipoma and oncocytoma. Radiologists need to know the recommendations for the management of these lesions and the usefulness of the different imaging techniques and interventional procedures in function of the characteristics of the incidental lesion and the patient's life expectancy.

  5. Role of human papillomavirus and its detection in potentially malignant and malignant head and neck lesions: updated review.

    PubMed

    Chaudhary, Ajay Kumar; Singh, Mamta; Sundaram, Shanthy; Mehrotra, Ravi

    2009-06-25

    Head and neck malignancies are characterized by a multiphasic and multifactorial etiopathogenesis. Tobacco and alcohol consumption are the most common risk factors for head and neck malignancy. Other factors, including DNA viruses, especially human papilloma virus (HPV), may also play a role in the initiation or development of these lesions. The pathways of HPV transmission in the head and neck mucosal lesions include oral-genital contact, more than one sexual partner and perinatal transmission of HPV to the neonatal child. The increase in prevalence of HPV infection in these lesions may be due to wider acceptance of oral sex among teenagers and adults as this is perceived to be a form of safe sex. The prevalence of HPV in benign lesions as well as malignancies has been assessed by many techniques. Among these, the polymerase chain reaction is the most sensitive method. Review of literature reveals that HPV may be a risk factor for malignancies, but not in all cases. For confirmation of the role of HPV in head and neck squamous cell carcinoma, large population studies are necessary in an assortment of clinical settings. Prophylactic vaccination against high-risk HPV types eventually may prevent a significant number of cervical carcinomas. Of the two vaccines currently available, Gardasil (Merck & Co., Inc.) protects against HPV types 6, 11, 16 and 18, while the other vaccine, Cervarix (GlaxoSmithKline, Rixensart, Belgium) protects against HPV types 16 and 18 only. However, the HPV vaccine has, to the best of our knowledge, not been tried in head and neck carcinoma. The role of HPV in etiopathogenesis, prevalence in benign and malignant lesions of this area and vaccination strategies are briefly reviewed here.

  6. Value of Magnifying Endoscopy With Narrow-Band Imaging and Confocal Laser Endomicroscopy in Detecting Gastric Cancerous Lesions

    PubMed Central

    Gong, Shuai; Xue, Han-Bing; Ge, Zhi-Zheng; Dai, Jun; Li, Xiao-Bo; Zhao, Yun-Jia; Zhang, Yao; Gao, Yun-Jie; Song, Yan

    2015-01-01

    Abstract Although the respective potentials of magnifying endoscopy with narrow-band imaging (ME-NBI) and confocal laser endomicroscopy (CLE) in predicting gastric cancer has been well documented, there is a lack of studies in comparing the value and diagnostic strategy of these 2 modalities. Our primary aim is to investigate whether CLE is superior to ME-NBI for differentiation between gastric cancerous and noncancerous lesions. A secondary aim is to propose an applicable clinical strategy. We conducted a diagnostic accuracy study involving patients with suspected gastric superficial cancerous lesions. White light endoscopy, ME-NBI, and CLE were performed diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value between ME-NBI and CLE were assessed, as well as agreements between ME-NBI/CLE and histopathology. This study involved 86 gastric lesions in 82 consecutive patients who underwent white light endoscopy, ME-NBI, and CLE before biopsy. The accuracy, sensitivity, and specificity for ME-NBI were 93.75%, 91.67%, and 95.45%, compared with 91.86%, 90%, and 93.48%, respectively, for CLE, for discrimination cancerous/noncancerous lesion (all P > 0.05). For undifferentiated/differentiated adenocarcinoma, CLE had a numerically but not statistically significantly higher accuracy than ME-NBI (81.25% vs 73.33%, P = 0.46). Agreements between ME-NBI/CLE and histopathology were near perfect (ME-NBI, κ = 0.87; CLE, κ = 0.84). CLE is not superior to ME-NBI for discriminating gastric cancerous from noncancerous lesions. Endoscopist could make an optimal choice according to the specific indication and advantages of ME-NBI and CLE in daily practices. PMID:26554797

  7. HPV Genotypes in High Grade Cervical Lesions and Invasive Cervical Carcinoma as Detected by Two Commercial DNA Assays, North Carolina, 2001–2006

    PubMed Central

    Hariri, Susan; Steinau, Martin; Rinas, Allen; Gargano, Julia W.; Ludema, Christina; Unger, Elizabeth R.; Carter, Alicia L.; Grant, Kathy L.; Bamberg, Melanie; McDermott, James E.; Markowitz, Lauri E.; Brewer, Noel T.; Smith, Jennifer S.

    2012-01-01

    Background HPV typing using formalin fixed paraffin embedded (FFPE) cervical tissue is used to evaluate HPV vaccine impact, but DNA yield and quality in FFPE specimens can negatively affect test results. This study aimed to evaluate 2 commercial assays for HPV detection and typing using FFPE cervical specimens. Methods Four large North Carolina pathology laboratories provided FFPE specimens from 299 women ages18 and older diagnosed with cervical disease from 2001 to 2006. For each woman, one diagnostic block was selected and unstained serial sections were prepared for DNA typing. Extracts from samples with residual lesion were used to detect and type HPV using parallel and serial testing algorithms with the Linear Array and LiPA HPV genotyping assays. Findings LA and LiPA concordance was 0.61 for detecting any high-risk (HR) and 0.20 for detecting any low-risk (LR) types, with significant differences in marginal proportions for HPV16, 51, 52, and any HR types. Discordant results were most often LiPA-positive, LA-negative. The parallel algorithm yielded the highest prevalence of any HPV type (95.7%). HR type prevalence was similar using parallel (93.1%) and serial (92.1%) approaches. HPV16, 33, and 52 prevalence was slightly lower using the serial algorithm, but the median number of HR types per woman (1) did not differ by algorithm. Using the serial algorithm, HPV DNA was detected in >85% of invasive and >95% of pre-invasive lesions. The most common type was HPV16, followed by 52, 18, 31, 33, and 35; HPV16/18 was detected in 56.5% of specimens. Multiple HPV types were more common in lower grade lesions. Conclusions We developed an efficient algorithm for testing and reporting results of two commercial assays for HPV detection and typing in FFPE specimens, and describe HPV type distribution in pre-invasive and invasive cervical lesions in a state-based sample prior to HPV vaccine introduction. PMID:22479516

  8. Polycystic kidney disease in tuberous sclerosis complex: case report.

    PubMed

    Kariuki, N; Karanja, M N; McLigeyo, S O

    1998-10-01

    Tuberous sclerosis complex (TSC) is an inherited neurocutaneous disorder characterised by seizures, mental retardation, cutaneous lesions and visceral harmatoma. We describe a 4 1/2-year old boy in whom in addition to the commonly described features of TSC, adult-type polycystic kidneys, a scantily reported occurrence, was an associated feature. PMID:10065200

  9. Multiple sclerosis

    PubMed Central

    Rühl, Geraldine; Niedl, Anna G.; Patronov, Atanas; Siewert, Katherina; Pinkert, Stefan; Kalemanov, Maria; Friese, Manuel A.; Attfield, Kathrine E.; Antes, Iris; Hohlfeld, Reinhard

    2016-01-01

    Objective: To identify target antigens presented by human leukocyte antigen (HLA)–A*02:01 to the myelin-reactive human T-cell receptor (TCR) 2D1, which was originally isolated from a CD8+ T-cell clone recognizing proteolipid protein (PLP) in the context of HLA-A*03:01, we employed a new antigen search technology. Methods: We used our recently developed antigen search technology that employs plasmid-encoded combinatorial peptide libraries and a highly sensitive single cell detection system to identify endogenous candidate peptides of mice and human origin. We validated candidate antigens by independent T-cell assays using synthetic peptides and refolded HLA:peptide complexes. A molecular model of HLA-A*02:01:peptide complexes was obtained by molecular dynamics simulations. Results: We identified one peptide from glycerolphosphatidylcholine phosphodiesterase 1, which is identical in mice and humans and originates from a protein that is expressed in many cell types. When bound to HLA-A*02:01, this peptide cross-stimulates the PLP-reactive HLA-A3-restricted TCR 2D1. Investigation of molecular details revealed that the peptide length plays a crucial role in its capacity to bind HLA-A*02:01 and to activate TCR 2D1. Molecular modeling illustrated the 3D structures of activating HLA:peptide complexes. Conclusions: Our results show that our antigen search technology allows us to identify new candidate antigens of a presumably pathogenic, autoreactive, human CD8+ T-cell-derived TCR. They further illustrate how this TCR, which recognizes a myelin peptide bound to HLA-A*03:01, may cross-react with an unrelated peptide presented by the protective HLA class I allele HLA-A*02:01. PMID:27231714

  10. Validity and reproducibility of a laser fluorescence system for detecting the activity of white-spot lesions on free smooth surfaces in vivo.

    PubMed

    Pinelli, Camila; Campos Serra, Mônica; de Castro Monteiro Loffredo, Leonor

    2002-01-01

    The aim of the study was to determine the reproducibility and validity of DIAGNOdent in detecting active and arrested caries lesions on free smooth surfaces. Volunteers were selected from state schools of Piracicaba, São Paulo, Brazil. Overall, 220 lesions were clinically examined. Two specially trained ('calibrated') examiners performed both clinical and laser evaluations independently, and after a 1-week interval, the examinations were repeated. The intra-examiner agreement for the laser evaluation was substantial (kappa(ex1) = 0.79, kappa(ex2) = 0.71). There was almost perfect agreement between the two examiners for the clinical examination (kappa(ex1) = 0.95, kappa(ex2) = 0.85). The inter-examiner agreement showed substantial reproducibility (kappa = 0.77) for the laser examination and almost perfect agreement (kappa = 0.85) for the clinical evaluation. The validation criterion was the clinical examination of white spots, recorded as active or arrested. The sensitivity was 0.72 and the specificity was 0.73, which indicates that the DIAGNOdent was a good auxiliary method for detecting incipient caries lesions on free smooth surfaces. The utilization of both methods can improve the efficacy of caries diagnosis.

  11. Detection of human papillomavirus DNA in genital lesions by enzymatic in situ hybridization with Fast Red and laser scanning confocal microscopy.

    PubMed

    Lizard, G; Chignol, M C; Roignot, P; Souchier, C; Chardonnet, Y; Schmitt, D

    1997-07-01

    Human papillomavirus (HPV) infection with potentially oncogenic types 16 or 18 is common in genital lesions especially in uterine carcinomas. In such lesions, in situ hybridization with non-radioactive probes is a powerful tool for the histopathologist to detect and type HPV DNA either on cell deposits or on tissue sections. The use of an immunohistochemical method involving alkaline phosphatase and Fast Red TR salt/naphthol AS-MX phosphate is proposed for use with conventional bright-field or fluorescence microscopy as well as by laser scanning confocal microscopy. The alkaline phosphatase-Fast Red reaction has the advantage of producing a red precipitate that permits the detection of in situ hybridization signals by bright-field microscopy, and of obtaining a strong red fluorescence characterized by a lack of bleaching when excited by a green light. Therefore, the alkaline phosphatase-Fast Red reaction is well adapted for observations by fluorescence and confocal microscopy, the latter method allowing the detection, in tissue sections of cervical intraepithelial lesions, of small punctate and large diffuse hybridization signals, considered as integrated and episomal states of HPV DNA respectively. The combination of in situ hybridization with the alkaline phosphatase-Fast Red reaction and confocal microscopy is particularly convincing when hybridization signals are of small size and/or of low fluorescence intensity, especially if they are present in various focal planes; in such conditions, infected cells are easily detected by three-dimensional reconstruction. Therefore, this combination is a suitable method for identifying and characterizing HPV DNA in cells and tissue sections.

  12. The formation of inflammatory demyelinated lesions in cerebral white matter

    PubMed Central

    Maggi, Pietro; Cummings Macri, Sheila M.; Gaitán, María I.; Leibovitch, Emily; Wholer, Jillian E; Knight, Heather L.; Ellis, Mary; Wu, Tianxia; Silva, Afonso C.; Massacesi, Luca; Jacobson, Steven; Westmoreland, Susan; Reich, Daniel S.

    2016-01-01

    Objective Vascular permeability and inflammatory demyelination are intimately linked in the brain, but what is their temporal relationship? We aimed to determine the radiological correlates of the earliest tissue changes accompanying demyelination in a primate model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE) in the common marmoset. Methods At 7 tesla MRI, T1 maps, proton density and T2-weighted images were acquired before and after EAE induction in 5 marmosets (every other week before lesions appeared, weekly thereafter). From scans before and after intravenous injection of contrast material, we measured the evolution of lesional blood-brain-barrier (BBB) permeability, comparing in vivo MRI to postmortem tissue examination. Results On average, BBB permeability increased 3.5 fold (p<0.0001) over the 4 weeks prior to lesion appearance. Permeability gradually decreased after lesion appearance, with attendant changes in the distribution of inflammatory cells (predominantly macrophages and microglia) and demyelination. On tissue analysis, we also identified small perivascular foci of microglia and T cells without blood-derived macrophages or demyelination. These foci had no visible MRI correlates, though permeability within the foci, but not outside, increased in the weeks before the animals died (p<0.0001). Interpretation This study provides compelling evidence that in marmoset EAE, which forms lesions strongly resembling those of MS, early changes in vascular permeability are associated with perivascular inflammatory cuffing and parenchymal microglial activation but precede the arrival of blood-derived monocytes that accompany demyelination. Prospective detection of transient permeability changes could afford an opportunity for early intervention to forestall tissue damage in newly forming lesions. PMID:25088017

  13. Mitochondrial DNA mutations in preneoplastic lesions of the gastrointestinal tract: A biomarker for the early detection of cancer

    PubMed Central

    Sui, Guoping; Zhou, Shaoyu; Wang, Jean; Canto, Marcia; Lee, Edward E; Eshleman, James R; Montgomery, Elizabeth A; Sidransky, David; Califano, Joseph A; Maitra, Anirban

    2006-01-01

    Background Somatic mutations of mitochondrial DNA (mtDNA) are common in many human cancers. We have described an oligonucleotide microarray ("MitoChip") for rapid sequencing of the entire mitochondrial genome (Zhou et al, J Mol Diagn 2006), facilitating the analysis of mtDNA mutations in preneoplastic lesions. We examined 14 precancerous lesions, including seven Barrett esophagus biopsies, with or without associated dysplasia; four colorectal adenomas; and three inflammatory colitis-associated dysplasia specimens. In all cases, matched normal tissues from the corresponding site were obtained as germline control. MitoChip analysis was performed on DNA obtained from cryostat-embedded specimens. Results A total of 513,639 bases of mtDNA were sequenced in the 14 samples, with 490,224 bases (95.4%) bases assigned by the automated genotyping software. All preneoplastic lesions examined demonstrated at least one somatic mtDNA sequence alteration. Of the 100 somatic mtDNA alterations observed in the 14 cases, 27 were non-synonymous coding region mutations (i.e., resulting in an amino acid change), 36 were synonymous, and 37 involved non-coding mtDNA. Overall, somatic alterations most commonly involved the COI, ND4 and ND5 genes. Notably, somatic mtDNA alterations were observed in preneoplastic lesions of the gastrointestinal tract even in the absence of histopathologic evidence of dysplasia, suggesting that the mitochondrial genome is susceptible at the earliest stages of multistep cancer progression. Conclusion Our findings further substantiate the rationale for exploring the mitochondrial genome as a biomarker for the early diagnosis of cancer, and confirm the utility of a high-throughput array-based platform for this purpose from a clinical applicability standpoint. PMID:17166268

  14. Detection of bovine papilloma viruses in wart-like lesions of upper gastrointestinal tract of cattle and buffaloes.

    PubMed

    Kumar, P; Nagarajan, N; Saikumar, G; Arya, R S; Somvanshi, R

    2015-06-01

    In present investigation, etiopathological characterization of upper gastrointestinal tract (GIT) tumours of cattle and buffaloes was undertaken. A total of 27 GIT wart-like lesions in rumen, reticulum, mouth and oesophagus of cattle and buffaloes revealed the presence of small nodular to larger spherical or slender growths with thin base present on mucosa and ruminal pillar. Histopathologically, these cases were diagnosed as fibropapilloma/papilloma. This is the first world record on ruminal papillomatosis in buffaloes. Ruminal warts of cattle and buffaloes revealed the presence of BPV-5, -1 & -2, which is the first report of presence of these BPVs in the ruminal warts from India. Quantitative real-time PCR revealed that DNA samples of different GIT wart-like lesions contained varying amount of BPV DNA copy numbers. Immunohistochemistry revealed that the PCNA and Ki67 immunopositivity was present in the basal and spinosum layer of the fibropapilloma/papilloma, indicating these as the cellular proliferation site. In conclusion, the present investigation revealed that BPV-5, -1 & -2 are associated with certain ruminal wart-like lesions/growths in cattle and buffaloes, and the basal and spinosum layer of the ruminal fibropapilloma/papilloma were cellular proliferation sites.

  15. Role of Chlamydia in Multiple Sclerosis.

    PubMed

    Ivanova, M V; Kolkova, N I; Morgunova, E Yu; Pashko, Yu P; Zigangirova, N A; Zakharova, M N

    2015-09-01

    Chlamydia and antibodies to them were detected by serological, molecular biological, and culture methods in the sera and cerebrospinal fluid of patients with multiple sclerosis and in the reference groups of subjects without neurological diseases. Correlations between the agent presence in the biological fluids of patients and clinical characteristics of the disease were analyzed. C. pneumoniae were more incident in the biological liquids of patients with multiple sclerosis than in healthy volunteers. On the other hand, the incidence of the agent in the patients was not high and its presence did not correlate with the clinical manifestations. C. trachomatis was equally rare in the patients and volunteers. The studies indicated the existence of a group of patients infected by C. pneumoniae in the cohort of patients with multiple sclerosis, but the impact of this agent for the disease course remains unclear.

  16. Widespread grey matter pathology dominates the longitudinal cerebral MRI and clinical landscape of amyotrophic lateral sclerosis.

    PubMed

    Menke, Ricarda A L; Körner, Sonja; Filippini, Nicola; Douaud, Gwenaëlle; Knight, Steven; Talbot, Kevin; Turner, Martin R

    2014-09-01

    Diagnosis, stratification and monitoring of disease progression in amyotrophic lateral sclerosis currently rely on clinical history and examination. The phenotypic heterogeneity of amyotrophic lateral sclerosis, including extramotor cognitive impairments is now well recognized. Candidate biomarkers have shown variable sensitivity and specificity, and studies have been mainly undertaken only cross-sectionally. Sixty patients with sporadic amyotrophic lateral sclerosis (without a family history of amyotrophic lateral sclerosis or dementia) underwent baseline multimodal magnetic resonance imaging at 3 T. Grey matter pathology was identified through analysis of T1-weighted images using voxel-based morphometry. White matter pathology was assessed using tract-based spatial statistics analysis of indices derived from diffusion tensor imaging. Cross-sectional analyses included group comparison with a group of healthy controls (n = 36) and correlations with clinical features, including regional disability, clinical upper motor neuron signs and cognitive impairment. Patients were offered 6-monthly follow-up MRI, and the last available scan was used for a separate longitudinal analysis (n = 27). In cross-sectional study, the core signature of white matter pathology was confirmed within the corticospinal tract and callosal body, and linked strongly to clinical upper motor neuron burden, but also to limb disability subscore and progression rate. Localized grey matter abnormalities were detected in a topographically appropriate region of the left motor cortex in relation to bulbar disability, and in Broca's area and its homologue in relation to verbal fluency. Longitudinal analysis revealed progressive and widespread changes in the grey matter, notably including the basal ganglia. In contrast there was limited white matter pathology progression, in keeping with a previously unrecognized limited change in individual clinical upper motor neuron scores, despite advancing disability

  17. Is virtual chromoendoscopy useful in the evaluation of subtle ulcerative small-bowel lesions detected by video capsule endoscopy?

    PubMed Central

    Rimbaş, Mihai; Negreanu, Lucian; Ciobanu, Lidia; Benguş, Andreea; Spada, Cristiano; Băicuş, Cristian Răsvan; Costamagna, Guido

    2015-01-01

    Background: The identification of subtle small-bowel mucosal lesions by video capsule endoscopy (VCE) can be challenging. Virtual chromoendoscopy techniques, based on narrowing the bandwidth of conventional white light endoscopic imaging (WLI), were developed to improve the analysis of mucosal patterns. However, data on the already-implemented Flexible spectral Imaging (or Fujinon Intelligent) Color Enhancement (FICE) software application in VCE are limited. Materials and methods: An evaluation of 250 difficult-to-interpret small-bowel ulcerative and 50 artifact lesions selected from 64 VCE recordings was conducted by four experienced VCE readers in two steps: initially as WLI, then with the addition of all available virtual chromoendoscopy pre-sets (FICE 1, 2, and 3 and Blue mode). The readers labeled them as real or false ulcerative lesions and rated the usefulness of each of the pre-sets. Results: Between the first (WLI-only) and second (virtual chromoendoscopy-aided) readings, in terms of accuracy there was a global 16.5 % (95 % confidence interval [95 %CI] 13.6 – 19.4 %) improvement (P < 0.001), derived from a 22 % [95 %CI 18.9 – 25.1 %] improvement in the evaluation of true ulcerative images (P < 0.001) and an 11 % (95 %CI 4.1 – 17.7 %) decrease in the evaluation of false ulcerative ones (P = 0.003). The FICE 1 and 2 pre-sets were rated as most useful. Conclusion: The application of virtual chromoendoscopy for VCE is useful to better categorize difficult-to-interpret small-bowel mucosal ulcerative lesions. However, care must be taken, and individual images should be evaluated only as part of a sequence in a recording because the technology can also mistakenly guide to the incorrect interpretation of artifacts as ulcerative lesions. PMID:26716122

  18. Viruses and Multiple Sclerosis

    PubMed Central

    Virtanen, Jussi Oskari; Jacobson, Steve

    2016-01-01

    Multiple sclerosis (MS) is a heterogeneous disease that develops as an interplay between the immune system and environmental stimuli in genetically susceptible individuals. There is increasing evidence that viruses may play a role in MS pathogenesis acting as these environmental triggers. However, it is not known if any single virus is causal, or rather several viruses can act as triggers in disease development. Here, we review the association of different viruses to MS with an emphasis on two herpesviruses, Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV-6). These two agents have generated the most impact during recent years as possible co-factors in MS disease development. The strongest argument for association of EBV with MS comes from the link between symptomatic infectious mononucleosis and MS and from seroepidemiological studies. In contrast to EBV, HHV-6 has been found significantly more often in MS plaques than in MS normal appearing white matter or non-MS brains and HHV-6 re-activation has been reported during MS clinical relapses. In this review we also suggest new strategies, including the development of new infectious animal models of MS and antiviral MS clinical trials, to elucidate roles of different viruses in the pathogenesis of this disease. Furthermore, we introduce the idea of using unbiased sequence-independent pathogen discovery methodologies, such as next generation sequencing, to study MS brain tissue or body fluids for detection of known viral sequences or potential novel viral agents. PMID:22583435

  19. [Psychoneuroimmunology and multiple sclerosis].

    PubMed

    Mel'nikov, M V; Pashchenkov, M V; Boĭko, A N

    2015-01-01

    In this review, the authors discuss interactions between mental, nervous and immune systems in multiple sclerosis, an impact of psycho-emotional stress on disease development and progression as well as possible mechanisms of these interactions.

  20. Amyotrophic Lateral Sclerosis

    MedlinePlus

    Amyotrophic lateral sclerosis (ALS) is a nervous system disease that attacks nerve cells called neurons in your ... people with ALS die from respiratory failure. The disease usually strikes between age 40 and 60. More ...

  1. Systemic sclerosis: Recent insights.

    PubMed

    Elhai, Muriel; Avouac, Jérôme; Kahan, André; Allanore, Yannick

    2015-05-01

    Systemic sclerosis is an orphan connective tissue disease characterized by alterations of the microvasculature, disturbances of the immune system and massive deposition of collagen and other matrix substances in the skin and internal organs. A major achievement of the recent years has been the validation of new classification criteria, allowing earlier diagnosis and earlier treatment of systemic sclerosis, before irreversible fibrosis and organ damage appeared ("window of opportunity"). Raynaud's phenomenon is usually the first sign of the disease and is considered as the main sentinel sign for the identification of very early systemic sclerosis. Systemic sclerosis is clinically heterogeneous and disease course remains unpredictable. Its prognosis depends on cardiopulmonary involvement and recent studies aim to identify serum or genetic biomarkers predictive of severe organ involvement. Moreover, the prospective follow-up of large cohorts has provided and will offer critical material to identify strong prognostic factors. Whereas the outcomes of vascular manifestations of the disease has been recently improved due to targeted therapy, recent data have highlighted that mortality has not changed over the past 40 years. This reflects the absence of efficacy of current available drugs to counteract the fibrotic process. Nevertheless, several targeted immunity therapies, commonly with proven efficacy in other immune diseases, are about to be investigated in systemic sclerosis. Indeed, promising results in small and open studies have been reported. This article deals with recent insights into classification criteria, pathogenesis, organ involvements, outcome and current and possible future therapeutic options in systemic sclerosis.

  2. Patch-Based Segmentation with Spatial Consistency: Application to MS Lesions in Brain MRI.

    PubMed

    Mechrez, Roey; Goldberger, Jacob; Greenspan, Hayit

    2016-01-01

    This paper presents an automatic lesion segmentation method based on similarities between multichannel patches. A patch database is built using training images for which the label maps are known. For each patch in the testing image, k similar patches are retrieved from the database. The matching labels for these k patches are then combined to produce an initial segmentation map for the test case. Finally an iterative patch-based label refinement process based on the initial segmentation map is performed to ensure the spatial consistency of the detected lesions. The method was evaluated in experiments on multiple sclerosis (MS) lesion segmentation in magnetic resonance images (MRI) of the brain. An evaluation was done for each image in the MICCAI 2008 MS lesion segmentation challenge. Results are shown to compete with the state of the art in the challenge. We conclude that the proposed algorithm for segmentation of lesions provides a promising new approach for local segmentation and global detection in medical images. PMID:26904103

  3. Using digital subtraction in computer simulated images as a tool to aid the visual detection of masked lesions in dense breasts

    NASA Astrophysics Data System (ADS)

    Schiabel, Homero; Guimarães, Luciana T.; Sousa, Maria A. Z.

    2015-03-01

    This work proposes a simulation model involving subtraction of digital mammography images obtained at different X-ray beam levels of energy to aid the detection of breast malignant lesions. Absorption coefficients behavior of 3 main structures of clinical interest - adipose tissue, fiber glandular tissue and the typical carcinoma - as a function of the beam energy from a Mo X-ray tube was the basis to develop a computer simulation of the possible acquired images. The simulation has considered a typical compressed breast with 4.5cm in thickness, and variations of the carcinoma and glandular tissues thicknesses - 0.4 up to 2.0cm and 4.1 to 2.5cm, respectively - were evaluated as a function of the photons mean energy - 14 up to 25 keV, in the typical mammography energy range. Results have shown that: (a) if the carcinoma thickness is over 0.4cm, its detection may be feasible even masked by fiber tissue with exposures in the range of 19 to 25 keV; (b) for masked carcinoma with thickness in the range of 0.4-2.0cm, the proposed procedure can enhance it in the image resulting from the digital subtraction between images obtained at 14 and at 22 keV. Therefore such results indicate that this simulation procedure can be a useful tool in aiding the identification of possible missed malignant lesions which could not be detected in the typical exam, mainly considering dense breasts.

  4. The timing of bowel preparation before colonoscopy determines the quality of cleansing, and is a significant factor contributing to the detection of flat lesions: A randomized study

    PubMed Central

    Parra-Blanco, Adolfo; Nicolás-Pérez, David; Gimeno-García, Antonio; Grosso, Begoña; Jiménez, Alejandro; Ortega, Juan; Quintero, Enrique

    2006-01-01

    AIM: To compare the cleansing quality of polyethylene glycol electrolyte solution and sodium phosphate with different schedules of administration, and to evaluate whether the timing of the administration of bowel preparation affects the detection of polyps. METHODS: One hundred and seventy-seven consecutive outpatients scheduled for colonoscopy were randomized in one of four groups to receive polyethylene glycol electrolyte solution or oral sodium phosphate with two different timing schedules. Quality of cleansing, polyp detection, and tolerance were evaluated. RESULTS: Patients receiving polyethylene glycol or sodium phosphate on the same day as the colonoscopy, obtained good to excellent global cleansing scores more frequently than patients who received polyethylene glycol or sodium phosphate on the day prior to the procedure (P < 0.001). Flat lesions, but not flat adenomas, were more frequent in patients prepared on the same day (P = 0.02). CONCLUSION: The quality of colonic cleansing and the detection of flat lesions are significantly improved when the preparation is taken on the day of the colonoscopy. PMID:17036388

  5. Multiple sclerosis in children: an update on clinical diagnosis, therapeutic strategies, and research.

    PubMed

    Waldman, Amy; Ghezzi, Angelo; Bar-Or, Amit; Mikaeloff, Yann; Tardieu, Marc; Banwell, Brenda

    2014-09-01

    The clinical features, diagnostic challenges, neuroimaging appearance, therapeutic options, and pathobiological research progress in childhood-and adolescent-onset multiple sclerosis have been informed by many new insights in the past 7 years. National programmes in several countries, collaborative research efforts, and an established international paediatric multiple sclerosis study group have contributed to revised clinical diagnostic definitions, identified clinical features of multiple sclerosis that differ by age of onset, and made recommendations regarding the treatment of paediatric multiple sclerosis. The relative risks conveyed by genetic and environmental factors to paediatric multiple sclerosis have been the subject of several large cohort studies. MRI features have been characterised in terms of qualitative descriptions of lesion distribution and applicability of MRI aspects to multiple sclerosis diagnostic criteria, and quantitative studies have assessed total lesion burden and the effect of the disease on global and regional brain volume. Humoral-based and cell-based assays have identified antibodies against myelin, potassium-channel proteins, and T-cell profiles that support an adult-like T-cell repertoire and cellular reactivity against myelin in paediatric patients with multiple sclerosis. Finally, the safety and efficacy of standard first-line therapies in paediatric multiple sclerosis populations are now appreciated in more detail, and consensus views on the future conduct and feasibility of phase 3 trials for new drugs have been proposed. PMID:25142460

  6. Primary Position Upbeat Nystagmus during an Acute Attack of Multiple Sclerosis

    PubMed Central

    Kim, Jee-Ae; Jeong, In-Hye; Lim, Young-Min

    2014-01-01

    Background and Purpose Ocular manifestation is one of the frequent signs of an acute attack in multiple sclerosis (MS), although primary position upbeat nystagmus (PPUN) is rare. The purpose of this study is to determine the incidence of PPUN in MS and to determine the lesions that are responsible for this sign. Methods The medical records of 120 MS patients with acute brain lesions were reviewed over a consecutive period of 9 years; of these, 6 patients were found to have PPUN. Other ocular motor abnormalities were analyzed in combination with upbeat nystagmus, video-oculographic findings, and lesions detected on brain MRI. Results Lesions in the pontine tegmentum involving the medial longitudinal fasciculus (MLF) and ventral tegmental tract (VTT) were the most common, being observed in three of the six patients with PPUN. One patient exhibited caudal medullary lesions bilaterally affecting the paramedian portion of the posterior tegmentum, and two patients exhibited multiple lesions involving the pons with the cerebral peduncle or medulla. In five patients, other ocular motor dysfunctions, such as gaze-evoked nystagmus (n=3) and internuclear ophthalmoplegia (n=1), were found in combination with upbeat nystagmus. Conclusions PPUN is an infrequent, ocular manifestation noted during an acute attack of MS, and was observed in 5% of the present cases. Brainstem lesions in these cases primarily involved the pontine tegmentum and the caudal medulla. These findings support the theory that upbeat nystagmus is attributable to damage to the upward vestibulo-ocular reflex pathway related to the vestibular nucleus, VTT, and interconnecting pathways. PMID:24465261

  7. [Cervix uteri lesions and human papiloma virus infection (HPV): detection and characterization of DNA/HPV using PCR (polymerase chain reaction].

    PubMed

    Serra, H; Pista, A; Figueiredo, P; Urbano, A; Avilez, F; De Oliveira, C F

    2000-01-01

    The prevalence of human papillomavirus (HPV) genotypes was estimated by the polymerase chain reaction (PCR), in archival paraffin was embedded tissues. The case group consisted of 84 women aged 21-67 years (mean, 40 years) who were referred to the Department of Gynaecology (Oncology Centre, Coimbra) with citopathologically abnormal smears. This group was selected from a population of women who had undergone a screening programme (1990/94) in Central Region of Portugal. All these patients (n = 84) had a colposcopic directed cervical biopsy. HPV detection and typing was performed by the PCR method in the Department of Virology (National Health Care Institute, Lisbon). The prevalence of DNA/HPV found, concerning all epithelial cervical lesions studied and classified as squamous intra-epithelial lesions (SIL) and cervical cancer was 97.8%. On the basis of the data presented in this study, it was estimated that there was a statistically significant prevalence of low risk HPV types (HPV 6/11) in low grade SIL, 83.3%, and a statistically significant prevalence of high risk HPV types (HPV 16,18,31,33,51) in high grade SIL, 58.4%, as well as cervical cancer lesions in 100%. We conclude that there was a statistically significant difference between women with low and high grade SIL for HPV infection, with low and high risk HPV types, respectively. The risk factors for cervical cancer investigated (age at first sexual intercourse, multiple sexual partners, parity, use of oral contraceptives) were not associated to statistically significant differences concerning low grade SIL and high grade SIL. The clinical and therapeutic procedures were evaluated for the same five years (1990/94). It may be concluded that there would be no significant difference in clinical procedure for high grade lesions and cervical cancer, in which the treatment had been frequently radical (cone biopsies, simple or radical hysterectomy) and in which the HPV infection persisted frequently and was

  8. Diffusion Weighted Callosal Integrity Reflects Interhemispheric Communication Efficiency in Multiple Sclerosis

    ERIC Educational Resources Information Center

    Warlop, Nele P.; Achten, Eric; Debruyne, Jan; Vingerhoets, Guy

    2008-01-01

    We aimed to investigate the relation between damage in the corpus callosum and the performance on an interhemispheric communication task in patients with multiple sclerosis (MS). Relative callosal lesion load defined as the ratio between callosal area and the total lesion load in the total corpus callosum, and the diffusion tensor imaging (DTI)…

  9. VivaScope® 1500 and 3000 systems for detecting and monitoring skin lesions: a systematic review and economic evaluation.

    PubMed Central

    Edwards, Steven J; Mavranezouli, Ifigeneia; Osei-Assibey, George; Marceniuk, Gemma; Wakefield, Victoria; Karner, Charlotta

    2016-01-01

    BACKGROUND Skin cancer is one of the most common cancers in the UK. The main risk factor is exposure to ultraviolet radiation from sunlight or the use of sunbeds. Patients with suspicious skin lesions are first examined with a dermoscope. After examination, those with non-cancerous lesions are discharged, but lesions that are still considered clinically suspicious are surgically removed. VivaScope(®) is a non-invasive technology designed to be used in conjunction with dermoscopy to provide a more accurate diagnosis, leading to fewer biopsies of benign lesions or to provide more accurate presurgical margins reducing the risk of cancer recurrence. OBJECTIVES To evaluate the clinical effectiveness and cost-effectiveness of VivaScope(®) 1500 (Caliber Imaging and Diagnostics, Rochester, NY, USA; Lucid Inc., Rochester, NY, USA; or Lucid Inc., MAVIG GmbH, Munich, Germany) and VivaScope(®) 3000 (Caliber Imaging and Diagnostics, Rochester, NY, USA) in the diagnosis of equivocal skin lesions, and VivaScope 3000 in lesion margin delineation prior to surgical excision of lesions. DATA SOURCES Databases (MEDLINE, EMBASE and The Cochrane Library) were searched on 14 October 2014, reference lists of included papers were assessed and clinical experts were contacted for additional information on published and unpublished studies. METHODS A systematic review was carried out to identify randomised controlled trials (RCTs) or observational studies evaluating dermoscopy plus VivaScope, or VivaScope alone, with histopathology as the reference test. A probabilistic de novo economic model was developed to synthesise the available data on costs and clinical outcomes from the UK NHS perspective. All costs were expressed as 2014 prices. RESULTS Sixteen studies were included in the review, but they were too heterogeneous to be combined in a meta-analysis. One of two diagnostic studies that were deemed most representative of UK clinical practice reported that dermoscopy plus VivaScope 1500

  10. VivaScope® 1500 and 3000 systems for detecting and monitoring skin lesions: a systematic review and economic evaluation.

    PubMed Central

    Edwards, Steven J; Mavranezouli, Ifigeneia; Osei-Assibey, George; Marceniuk, Gemma; Wakefield, Victoria; Karner, Charlotta

    2016-01-01

    BACKGROUND Skin cancer is one of the most common cancers in the UK. The main risk factor is exposure to ultraviolet radiation from sunlight or the use of sunbeds. Patients with suspicious skin lesions are first examined with a dermoscope. After examination, those with non-cancerous lesions are discharged, but lesions that are still considered clinically suspicious are surgically removed. VivaScope(®) is a non-invasive technology designed to be used in conjunction with dermoscopy to provide a more accurate diagnosis, leading to fewer biopsies of benign lesions or to provide more accurate presurgical margins reducing the risk of cancer recurrence. OBJECTIVES To evaluate the clinical effectiveness and cost-effectiveness of VivaScope(®) 1500 (Caliber Imaging and Diagnostics, Rochester, NY, USA; Lucid Inc., Rochester, NY, USA; or Lucid Inc., MAVIG GmbH, Munich, Germany) and VivaScope(®) 3000 (Caliber Imaging and Diagnostics, Rochester, NY, USA) in the diagnosis of equivocal skin lesions, and VivaScope 3000 in lesion margin delineation prior to surgical excision of lesions. DATA SOURCES Databases (MEDLINE, EMBASE and The Cochrane Library) were searched on 14 October 2014, reference lists of included papers were assessed and clinical experts were contacted for additional information on published and unpublished studies. METHODS A systematic review was carried out to identify randomised controlled trials (RCTs) or observational studies evaluating dermoscopy plus VivaScope, or VivaScope alone, with histopathology as the reference test. A probabilistic de novo economic model was developed to synthesise the available data on costs and clinical outcomes from the UK NHS perspective. All costs were expressed as 2014 prices. RESULTS Sixteen studies were included in the review, but they were too heterogeneous to be combined in a meta-analysis. One of two diagnostic studies that were deemed most representative of UK clinical practice reported that dermoscopy plus VivaScope 1500

  11. Multiple sclerosis, an unlikely cause of chronic cerebrospinal venous insufficiency: retrospective analysis of catheter venography

    PubMed Central

    Simka, Marian; Ludyga, Tomasz; Kazibudzki, Marek; Latacz, Paweł; Świerad, Marcin

    2012-01-01

    Objectives It is unknown if a relationship exists between multiple sclerosis and chronic cerebrospinal venous insufficiency and if this venous pathology is a causal factor for multiple sclerosis or is a product of a neurological disease. Even so, one should expect that if multiple sclerosis were the cause for venous lesions, then patients with an extended history of the disease would present with a more severe venous pathology. Design Retrospective analysis of catheter venography of the azygous and internal jugular veins, and duration of clinical history of the disease in multiple sclerosis patients. Setting Mono-profile specialist hospital. Participants 353 multiple sclerosis patients, with duration of the disease: 0.5-41 years (median: 10 years). Main outcome measures We performed statistical analysis of the correlations between the duration of multiple sclerosis and the degree and number of venous lesions revealed using catheter venography. Results We observed weak, statistically insignificant correlations between the severity of chronic cerebrospinal venous insufficiency and the duration of multiple sclerosis. For the cumulated scores of venous lesions, Spearman and Kendall's tau correlation coefficients were 0.03 and 0.02, respectively; for maximal scores of venous lesions, coefficients were 0.06 and 0.05, while for the number of diseased veins they were 0.007 and 0.006, respectively. Consequently, this analysis did not yield any data supporting the idea that MS is the cause of venous lesions. Conclusion The results of our survey indicated that venous malformations are most likely congenital, and multiple sclerosis had no significant impact on the development of venous pathology. PMID:23301144

  12. Pulmonary hyalinizing granuloma: an unusual association with multiple sclerosis.

    PubMed

    John, P G; Rahman, J; Payne, C B

    1995-10-01

    Pulmonary hyalinizing granuloma (PHG) is a rare entity included in the differential diagnosis of pulmonary nodules of unknown origin. The pathologic entity may represent a peculiar form of pulmonary immune reaction. We report the case of a 40-year-old white woman who had nodular lesions in both lung bases after a 10-year history of multiple sclerosis. An open lung biopsy was required to make the diagnosis. The association of pulmonary hyalinizing granuloma with multiple sclerosis could be coincidental, but since there is a possibility of immune reaction in the pathogenesis of both diseases, the association may be significant. PMID:7481968

  13. The simultaneous detection of mitochondrial DNA damage from sun-exposed skin of three whale species and its association with UV-induced microscopic lesions and apoptosis.

    PubMed

    Bowman, Amy; Martinez-Levasseur, Laura M; Acevedo-Whitehouse, Karina; Gendron, Diane; Birch-Machin, Mark A

    2013-07-01

    Due to life history and physiological constraints, cetaceans (whales) are unable to avoid prolonged exposure to external environmental insults, such as solar ultraviolet radiation (UV). The majority of studies on the effects of UV on skin are restricted to humans and laboratory animals, but it is impor