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Sample records for sclerosis lesion detection

  1. Multiple Sclerosis Lesion Detection Using Constrained GMM and Curve Evolution

    PubMed Central

    Freifeld, Oren; Greenspan, Hayit; Goldberger, Jacob

    2009-01-01

    This paper focuses on the detection and segmentation of Multiple Sclerosis (MS) lesions in magnetic resonance (MRI) brain images. To capture the complex tissue spatial layout, a probabilistic model termed Constrained Gaussian Mixture Model (CGMM) is proposed based on a mixture of multiple spatially oriented Gaussians per tissue. The intensity of a tissue is considered a global parameter and is constrained, by a parameter-tying scheme, to be the same value for the entire set of Gaussians that are related to the same tissue. MS lesions are identified as outlier Gaussian components and are grouped to form a new class in addition to the healthy tissue classes. A probability-based curve evolution technique is used to refine the delineation of lesion boundaries. The proposed CGMM-CE algorithm is used to segment 3D MRI brain images with an arbitrary number of channels. The CGMM-CE algorithm is automated and does not require an atlas for initialization or parameter learning. Experimental results on both standard brain MRI simulation data and real data indicate that the proposed method outperforms previously suggested approaches, especially for highly noisy data. PMID:19756161

  2. Seven-Tesla Magnetization Transfer Imaging to Detect Multiple Sclerosis White Matter Lesions.

    PubMed

    Chou, I-Jun; Lim, Su-Yin; Tanasescu, Radu; Al-Radaideh, Ali; Mougin, Olivier E; Tench, Christopher R; Whitehouse, William P; Gowland, Penny A; Constantinescu, Cris S

    2017-09-25

    Fluid-attenuated inversion recovery (FLAIR) imaging at 3 Tesla (T) field strength is the most sensitive modality for detecting white matter lesions in multiple sclerosis. While 7T FLAIR is effective in detecting cortical lesions, it has not been fully optimized for visualization of white matter lesions and thus has not been used for delineating lesions in quantitative magnetic resonance imaging (MRI) studies of the normal appearing white matter in multiple sclerosis. Therefore, we aimed to evaluate the sensitivity of 7T magnetization-transfer-weighted (MTw ) images in the detection of white matter lesions compared with 3T-FLAIR. Fifteen patients with clinically isolated syndrome, 6 with multiple sclerosis, and 10 healthy participants were scanned with 7T 3-dimensional (D) MTw and 3T-2D-FLAIR sequences on the same day. White matter lesions visible on either sequence were delineated. Of 662 lesions identified on 3T-2D-FLAIR images, 652 were detected on 7T-3D-MTw images (sensitivity, 98%; 95% confidence interval, 97% to 99%). The Spearman correlation coefficient between lesion loads estimated by the two sequences was .910. The intrarater and interrater reliability for 7T-3D-MTw images was good with an intraclass correlation coefficient (ICC) of 98.4% and 81.8%, which is similar to that for 3T-2D-FLAIR images (ICC 96.1% and 96.7%). Seven-Tesla MTw sequences detected most of the white matter lesions identified by FLAIR at 3T. This suggests that 7T-MTw imaging is a robust alternative for detecting demyelinating lesions in addition to 3T-FLAIR. Future studies need to compare the roles of optimized 7T-FLAIR and of 7T-MTw imaging. © 2017 The Authors. Journal of Neuroimaging published by Wiley Periodicals, Inc. on behalf of American Society of Neuroimaging.

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

    PubMed

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

    2013-12-07

    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.

  4. 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.

  5. 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.

  6. T1w dark blood imaging improves detection of contrast enhancing lesions in multiple sclerosis.

    PubMed

    Thaler, Christian; Schneider, Tanja; Sedlacik, Jan; Kutzner, Daniel; Stellmann, Jan-Patrick; Heesen, Christoph; Fiehler, Jens; Siemonsen, Susanne

    2017-01-01

    In multiple sclerosis (MS) the sensitivity for detection of contrast enhancing lesions (CEL) in T1-weighted scans is essential for diagnostics and therapy decisions. The purpose of our study was to evaluate the sensitivity of T1w MPRAGE scans in comparison to T1w dark blood technique (T1-DB) for CEL in MS. 3T MR imaging was performed in 37 MS patients, including T2-weighted imaging, T1w MPRAGE before and after gadolinium injection (unenhanced-T1 and T1-CE) and T1-DB imaging. After gadolinium application, the T1-DB scan was performed prior to T1-CE. From unenhanced-T1 and T1-CE scans, subtraction images (T1-SUB) were calculated. The number of CEL was determined separately on T1-CE and T1-DB by two raters independently. Lesions only detected on T1-DB scans then were verified on T1-SUB. Only lesions detected by both raters were included in further analysis. In 16 patients, at least one CEL was detected by both rater, either on T1-CE or T1-DB. All lesions that were detected on T1-CE were also detected on T1-DB images. The total number of contrast enhancing lesions detected on T1-DB images (n = 54) by both raters was significantly higher than the corresponding number of lesions identified on T1-CE (n = 27) (p = 0.01); all of these lesions could be verified on SUB images. In 21 patients, no CEL was detected in any of the sequences. The application of T1-DB technique increases the sensitivity for CEL in MS, especially for those lesions that show only subtle increase in intensity after Gadolinium application but remain hypo- or iso-intense to surrounding tissue.

  7. 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.

  8. Magnetic resonance diffusion tensor imaging for occult lesion detection in multiple sclerosis

    PubMed Central

    Chen, Jiafeng; Zhou, Chunkui; Zhu, Lijun; Yan, Xiuli; Wang, Yonghong; Chen, Xin; Fang, Shaokuan

    2017-01-01

    It remains challenging to locate occult lesions in patients with multiple sclerosis (MS). Diffusion tensor imaging (DTI) has been demonstrated to have the potential to identify occult changes in MS lesions. The present study used 3.0T magnetic resonance DTI to investigate the characteristics of different stages of MS lesions. DTI parameters, fractional anisotropy (FA), mean diffusivity (MD), λ// and λ┴ values of lesions were compared at the different stages of 10 patients with MS with 10 normal controls. The results demonstrated that FA and λ// values of MS silent and subacute lesions are decreased and MD and λ┴ values are increased, as compared with those of normal appearing white matter (NAWM) and normal controls. NAWM FA values were lower, and MD, λ//, and λ┴ values were higher than those of normal controls. It was also indicated that MS lesions had reduced color signals compared with the controls, and the lesion area appeared larger using DTI as compared with diffusion-weighted imaging. Furthermore, fiber abnormalities were detected in MS lesions using DTT, with fewer fibers connected to the lesion side, as compared with the contralateral side. FA, MD, λ// and λ┴ values in the thalamus were increased, as compared with those of normal controls (P<0.05); whereas MD, λ// and λ┴ values were significantly increased and FA values significantly decreased in the caudate nucleus and deep brain gray matter (DBGM) of patients with MS, as compared with the controls (P<0.05). λ// and λ┴ values were also significantly increased in the DBGM of patients with MS as compared with normal controls (P<0.05). The present findings demonstrate that DTI may be useful in the characterization of MS lesions. PMID:28123474

  9. Magnetic resonance diffusion tensor imaging for occult lesion detection in multiple sclerosis.

    PubMed

    Chen, Jiafeng; Zhou, Chunkui; Zhu, Lijun; Yan, Xiuli; Wang, Yonghong; Chen, Xin; Fang, Shaokuan

    2017-01-01

    It remains challenging to locate occult lesions in patients with multiple sclerosis (MS). Diffusion tensor imaging (DTI) has been demonstrated to have the potential to identify occult changes in MS lesions. The present study used 3.0T magnetic resonance DTI to investigate the characteristics of different stages of MS lesions. DTI parameters, fractional anisotropy (FA), mean diffusivity (MD), λ// and λ┴ values of lesions were compared at the different stages of 10 patients with MS with 10 normal controls. The results demonstrated that FA and λ// values of MS silent and subacute lesions are decreased and MD and λ┴ values are increased, as compared with those of normal appearing white matter (NAWM) and normal controls. NAWM FA values were lower, and MD, λ//, and λ┴ values were higher than those of normal controls. It was also indicated that MS lesions had reduced color signals compared with the controls, and the lesion area appeared larger using DTI as compared with diffusion-weighted imaging. Furthermore, fiber abnormalities were detected in MS lesions using DTT, with fewer fibers connected to the lesion side, as compared with the contralateral side. FA, MD, λ// and λ┴ values in the thalamus were increased, as compared with those of normal controls (P<0.05); whereas MD, λ// and λ┴ values were significantly increased and FA values significantly decreased in the caudate nucleus and deep brain gray matter (DBGM) of patients with MS, as compared with the controls (P<0.05). λ// and λ┴ values were also significantly increased in the DBGM of patients with MS as compared with normal controls (P<0.05). The present findings demonstrate that DTI may be useful in the characterization of MS lesions.

  10. Mitochondrial defects in acute multiple sclerosis lesions

    PubMed Central

    Mahad, Don; Ziabreva, Iryna; Turnbull, Douglas

    2008-01-01

    Multiple sclerosis is a chronic inflammatory disease, which leads to focal plaques of demyelination and tissue injury in the CNS. The structural and immunopathological patterns of demyelination suggest that different immune mechanisms may be involved in tissue damage. In a subtype of lesions, which are mainly found in patients with acute fulminant multiple sclerosis with Balo's type concentric sclerosis and in a subset of early relapsing remitting multiple sclerosis, the initial myelin changes closely resemble those seen in white matter stroke (WMS), suggesting a hypoxia-like tissue injury. Since mitochondrial injury may be involved in the pathogenesis of such lesions, we analysed a number of mitochondrial respiratory chain proteins in active lesions from acute multiple sclerosis and from WMS using immunohistochemistry. Functionally important defects of mitochondrial respiratory chain complex IV [cytochrome c oxidase (COX)] including its catalytic component (COX-I) are present in Pattern III but not in Pattern II multiple sclerosis lesions. The lack of immunohistochemically detected COX-I is apparent in oligodendrocytes, hypertrophied astrocytes and axons, but not in microglia. The profile of immunohistochemically detected mitochondrial respiratory chain complex subunits differs between multiple sclerosis and WMS. The findings suggest that hypoxia-like tissue injury in Pattern III multiple sclerosis lesions may be due to mitochondrial impairment. PMID:18515320

  11. Objective detection and localization of multiple sclerosis lesions on magnetic resonance brainstem images: validation with auditory evoked potentials.

    PubMed

    Stufflebeam, S M; Levine, R A; Gardner, J C; Fullerton, B C; Furst, M; Rosen, B R

    2000-01-01

    To develop an objective method for detecting multiple sclerosis (MS) brainstem lesions, magnetic resonance (MR) images (multiple planar, spin-echo, acquired in three planes of section) of sixteen MS patients and fourteen normal subjects were analyzed with an algorithm that detected regions with a relatively increased intensity on both a spin-echo image and a T2 image. To be considered a lesion, such regions had to overlap in at least two orthogonal planes. Using a digitized atlas of the human brainstem, the lesion locations were mapped with respect to the brainstem anatomy. This method was evaluated by comparing the location of MS lesions with the brainstem auditory evoked potentials obtained from these subjects. Brainstem lesions were detected in five MS patients; four had lesions impinging upon the auditory system and one did not. All four had abnormal evoked potentials. The fourteen normal subjects, the one MS patient with brainstem lesions outside the auditory pathway, and the eleven other MS patients with no brainstem lesions all had normal evoked potentials. The requirement that lesions be detected in at least two planes of section greatly improved the specificity of the algorithm. The consistency between the MR and brainstem auditory evoked potentials results supports the validity of this imaging analysis algorithm for objectively localizing brainstem lesions.

  12. Pediatric multiple sclerosis: detection of clinically silent lesions by multimodal evoked potentials.

    PubMed

    Pohl, Daniela; Rostasy, Kevin; Treiber-Held, Stephanie; Brockmann, Knut; Gärtner, Jutta; Hanefeld, Folker

    2006-07-01

    Pediatric patients with multiple sclerosis (MS) frequently do not meet MRI criteria for diagnosis because of lack of evidence of dissemination in space. We assessed the diagnostic utility of multimodal evoked potentials (EP). In 46% of 85 childhood patients with MS, spatial dissemination was detected by EP before the second clinical attack. EP may constitute an important tool for earlier diagnosis of pediatric MS.

  13. Focal cortical lesion detection in multiple sclerosis: 3 Tesla DIR versus 7 Tesla FLASH-T2.

    PubMed

    Nielsen, A Scott; Kinkel, R Philip; Tinelli, Emanuele; Benner, Thomas; Cohen-Adad, Julien; Mainero, Caterina

    2012-03-01

    To evaluate the inter-rater agreement of cortical lesion detection using 7 Tesla (T) FLASH-T2 and 3T DIR sequences. Twenty-six patients with multiple sclerosis were scanned on a human 7T (Siemens) and 3T MRI (TIM Trio, Siemens) to acquire 3T DIR/MEMPR and 7T FLASH-T2 sequences. Four independent reviewers scored and categorized cortical lesions in the bilateral precentral gyri (motor strips) as leukocortical, intracortical, or subpial. Inter-rater agreement was assessed according to lesion category using the kappa statistic. The sensitivity of recent MAGNIMS consensus guidelines for cortical lesion detection using 3T DIR was assessed with 7T FLASH-T2 as the reference gold standard. Inter-rater agreement at 7T was excellent compared with 3T (k = 0.97 versus 0.12). FLASH-T2 at 7T detected subpial lesions while 3T DIR did not. The predicted sensitivity of 3T DIR sequence for cortical lesions in vivo is modest (range of 13.6 to 18.3%). The 7T FLASH-T2 detects more cortical-particularly subpial-lesions compared with 3T DIR. In the absence of DIR/postmortem data, 7T FLASH-T2 is a suitable gold-standard instrument and should be incorporated into future consensus guidelines. Copyright © 2011 Wiley-Liss, Inc.

  14. Improved Automatic Detection of New T2 Lesions in Multiple Sclerosis Using Deformation Fields.

    PubMed

    Cabezas, M; Corral, J F; Oliver, A; Díez, Y; Tintoré, M; Auger, C; Montalban, X; Lladó, M; Pareto, D; Rovira, À

    2016-06-09

    Detection of disease activity, defined as new/enlarging T2 lesions on brain MR imaging, has been proposed as a biomarker in MS. However, detection of new/enlarging T2 lesions can be hindered by several factors that can be overcome with image subtraction. The purpose of this study was to improve automated detection of new T2 lesions and reduce user interaction to eliminate inter- and intraobserver variability. Multiparametric brain MR imaging was performed at 2 time points in 36 patients with new T2 lesions. Images were registered by using an affine transformation and the Demons algorithm to obtain a deformation field. After affine registration, images were subtracted and a threshold was applied to obtain a lesion mask, which was then refined by using the deformation field, intensity, and local information. This pipeline was compared with only applying a threshold, and with a state-of-the-art approach relying only on image intensities. To assess improvements, we compared the results of the different pipelines with the expert visual detection. The multichannel pipeline based on the deformation field obtained a detection Dice similarity coefficient close to 0.70, with a false-positive detection of 17.8% and a true-positive detection of 70.9%. A statistically significant correlation (r = 0.81, P value = 2.2688e-09) was found between visual detection and automated detection by using our approach. The deformation field-based approach proposed in this study for detecting new/enlarging T2 lesions resulted in significantly fewer false-positives while maintaining most true-positives and showed a good correlation with visual detection annotations. This approach could reduce user interaction and inter- and intraobserver variability. © 2016 American Society of Neuroradiology.

  15. Heterogeneity of Multiple Sclerosis White Matter Lesions Detected With T2*-Weighted Imaging at 7.0 Tesla.

    PubMed

    Yao, Bing; Ikonomidou, Vasiliki N; Cantor, Fredric K; Ohayon, Joan M; Duyn, Jeff; Bagnato, Francesca

    2015-01-01

    Postmortem studies in multiple sclerosis (MS) indicate that in some white matter lesions (WM-Ls), iron is detectable with T2*-weighted (T2*-w), and its reciprocal R2* relaxation rate, magnetic resonance imaging (MRI) at 7.0 Tesla (7T). This iron appears as a hyperintense rim in R2* images surrounding a hypointense core. We describe how this observation relates to clinical/radiological characteristics of patients, in vivo. We imaged 16 MS patients using 3T and 7T scanners. WM-Ls were identified on T1-w / T2-w 3T-MRIs. Thereafter, WM-Ls with a rim of elevated R2* at 7T were counted and compared to their appearance on conventional MRIs. We counted 36 WM-Ls presenting a rim of elevated R2* in 10 patients. Twenty-three (64%) lesions coincided with focal WM-Ls on T2-w MRIs; 13 (36%) coincided with only portions of larger lesions on T2-w images; and 20 (56%) corresponded to a hypointense chronic black hole. WM-Ls presenting a rim of elevated R2* were seen in both relapsing-remitting patients with low disability and in those with long-standing secondary progressive MS. WM-Ls with a contour of high R2* are present at different MS stages, potentially representing differences in the contribution of iron in MS disease evolution. Copyright © 2015 by the American Society of Neuroimaging.

  16. Fibronectin in multiple sclerosis lesions.

    PubMed Central

    Sobel, R. A.; Mitchell, M. E.

    1989-01-01

    Cryostat sections of central nervous system (CNS) tissues of patients with multiple sclerosis (MS) and other CNS diseases were stained with antibodies to fibronectin, a macrophage fibronectin receptor component, fibrin/fibrinogen, and albumin using immunoperoxidase. In active, but not inactive, MS plaques vessel fibronectin was increased (to approximately 57% of Factor VIII+ vessels) over uninvolved MS and normal control white matter (P less than 0.001 for both). Fibronectin was primarily localized to vessel walls and amount of staining correlated with degree of inflammation. Active plaques and necrotic lesions also had extracellular fibronectin and fibrin/ogen. These molecules and the fibronectin receptor were found on macrophages. Albumin was more widely and diffusely distributed in lesions than fibronectin. Thus, in addition to extravasation from damaged vessels, fibronectin may be deposited on or synthesized by endothelial cells and macrophages in the CNS. Fibronectin could facilitate monocyte adhesion to endothelial cell luminal surfaces, promote migration of mononuclear cells, and enhance myelin phagocytosis in MS lesions. Images Figure 1 Figure 2 PMID:2528301

  17. Longitudinal multiple sclerosis lesion segmentation data resource.

    PubMed

    Carass, Aaron; Roy, Snehashis; Jog, Amod; Cuzzocreo, Jennifer L; Magrath, Elizabeth; Gherman, Adrian; Button, Julia; Nguyen, James; Bazin, Pierre-Louis; Calabresi, Peter A; Crainiceanu, Ciprian M; Ellingsen, Lotta M; Reich, Daniel S; Prince, Jerry L; Pham, Dzung L

    2017-06-01

    The data presented in this article is related to the research article entitled "Longitudinal multiple sclerosis lesion segmentation: Resource and challenge" (Carass et al., 2017) [1]. In conjunction with the 2015 International Symposium on Biomedical Imaging, we organized a longitudinal multiple sclerosis (MS) lesion segmentation challenge providing training and test data to registered participants. The training data consists of five subjects with a mean of 4.4 (±0.55) time-points, and test data of fourteen subjects with a mean of 4.4 (±0.67) time-points. All 82 data sets had the white matter lesions associated with multiple sclerosis delineated by two human expert raters. The training data including multi-modal scans and manually delineated lesion masks is available for download. In addition, the testing data is also being made available in conjunction with a website for evaluating the automated analysis of the testing data.

  18. Increasing the sensitivity of MRI for the detection of multiple sclerosis lesions by long axial coverage of the spinal cord: a prospective study in 119 patients.

    PubMed

    Breckwoldt, Michael O; Gradl, Johann; Hähnel, Stefan; Hielscher, Thomas; Wildemann, Brigitte; Diem, Ricarda; Platten, Michael; Wick, Wolfgang; Heiland, Sabine; Bendszus, Martin

    2017-02-01

    Diagnostic imaging criteria of multiple sclerosis (MS) include the spatial and temporal dissemination of cerebral and/or spinal cord lesions. Magnetic resonance imaging (MRI) is the method of choice for initial diagnosis and follow-up disease monitoring. Current guidelines for spinal MRI recommend sagittal imaging of the spinal cord and lesion confirmation on axial planes if lesions are detected. Sagittal imaging is, however, hampered by technical (e.g. partial volume effects, motion artifacts) and anatomical (e.g. scoliosis) limitations. We hypothesized that long coverage of the spinal cord by axial image acquisition has superior diagnostic performance compared to sagittal imaging and can identify otherwise undetected lesions. Our prospective clinical study included 119 MS patients. Axial MRI revealed ~2.5-fold more lesions than the sagittal angulation (axial lesion load: 4.0 ± 2.4 vs. 1.6 ± 1.2 lesions on sagittal planes, p < 0.001). Importantly, 20 patients (17%) with normal sagittal MRI scans had unequivocal lesions only visible on axial planes (mean lesion number on axial planes in these patients: 2.0 ± 1.3). Moreover, 45 patients (38%) showed a discrepancy of ≥3 lesions that were found additionally on axial scans (mean difference 4.4 ± 1.7). Additionally identified lesions were on average smaller in size and located more laterally within the spinal cord. No lesion on sagittal images was missed on the axial angulation. Our study demonstrates that imaging of small axial segments for lesion confirmation is insufficient in spinal imaging. We recommend implementing a long coverage axial MRI sequence for spinal imaging of MS patients.

  19. Temporal Hierarchical Adaptive Texture CRF for Automatic Detection of Gadolinium-Enhancing Multiple Sclerosis Lesions in Brain MRI.

    PubMed

    Karimaghaloo, Zahra; Rivaz, Hassan; Arnold, Douglas L; Collins, D Louis; Arbel, Tal

    2015-06-01

    We propose a conditional random field (CRF) based classifier for segmentation of small enhanced pathologies. Specifically, we develop a temporal hierarchical adaptive texture CRF (THAT-CRF) and apply it to the challenging problem of gad enhancing lesion segmentation in brain MRI of patients with multiple sclerosis. In this context, the presence of many nonlesion enhancements (such as blood vessels) renders the problem more difficult. In addition to voxel-wise features, the framework exploits multiple higher order textures to discriminate the true lesional enhancements from the pool of other enhancements. Since lesional enhancements show more variation over time as compared to the nonlesional ones, we incorporate temporal texture analysis in order to study the textures of enhanced candidates over time. The parameters of the THAT-CRF model are learned based on 2380 scans from a multi-center clinical trial. The effect of different components of the model is extensively evaluated on 120 scans from a separate multi-center clinical trial. The incorporation of the temporal textures results in a general decrease of the false discovery rate. Specifically, THAT-CRF achieves overall sensitivity of 95% along with false discovery rate of 20% and average false positive count of 0.5 lesions per scan. The sensitivity of the temporal method to the trained time interval is further investigated on five different intervals of 69 patients. Moreover, superior performance is achieved by the reviewed labelings of our model compared to the fully manual labeling when applied to the context of separating different treatment arms in a real clinical trial.

  20. 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.

  1. Oxidative damage in multiple sclerosis lesions.

    PubMed

    Haider, Lukas; Fischer, Marie T; Frischer, Josa M; Bauer, Jan; Höftberger, Romana; Botond, Gergö; Esterbauer, Harald; Binder, Christoph J; Witztum, Joseph L; Lassmann, Hans

    2011-07-01

    Multiple sclerosis is a chronic inflammatory disease of the central nervous system, associated with demyelination and neurodegeneration. The mechanisms of tissue injury are currently poorly understood, but recent data suggest that mitochondrial injury may play an important role in this process. Since mitochondrial injury can be triggered by reactive oxygen and nitric oxide species, we analysed by immunocytochemistry the presence and cellular location of oxidized lipids and oxidized DNA in lesions and in normal-appearing white matter of 30 patients with multiple sclerosis and 24 control patients without neurological disease or brain lesions. As reported before in biochemical studies, oxidized lipids and DNA were highly enriched in active multiple sclerosis plaques, predominantly in areas that are defined as initial or 'prephagocytic' lesions. Oxidized DNA was mainly seen in oligodendrocyte nuclei, which in part showed signs of apoptosis. In addition, a small number of reactive astrocytes revealed nuclear expression of 8-hydroxy-d-guanosine. Similarly, lipid peroxidation-derived structures (malondialdehyde and oxidized phospholipid epitopes) were seen in the cytoplasm of oligodendrocytes and some astrocytes. In addition, oxidized phospholipids were massively accumulated in a fraction of axonal spheroids with disturbed fast axonal transport as well as in neurons within grey matter lesions. Neurons stained for oxidized phospholipids frequently revealed signs of degeneration with fragmentation of their dendritic processes. The extent of lipid and DNA oxidation correlated significantly with inflammation, determined by the number of CD3 positive T cells and human leucocyte antigen-D expressing macrophages and microglia in the lesions. Our data suggest profound oxidative injury of oligodendrocytes and neurons to be associated with active demyelination and axonal or neuronal injury in multiple sclerosis.

  2. Multiple sclerosis lesions of the auditory pons are not silent.

    PubMed

    Levine, R A; Gardner, J C; Fullerton, B C; Stufflebeam, S M; Furst, M; Rosen, B R

    1994-10-01

    To understand the relationship between brainstem lesions and auditory neurology in patients with multiple sclerosis, we compared behavioural, electrophysiological and imaging data in 38 patients with probable or definite multiple sclerosis and normal or near normal hearing. Behavioural measures included (i) general hearing tests (audiogram, speech discrimination) and (ii) hearing tests likely to be critically dependent upon brainstem processing (masking level difference, interaural time and level discrimination). Brainstem auditory evoked potentials provided the electrophysiological data. Multiplanar high-resolution MRI of the brainstem provided the anatomical data. Interaural time discrimination for high-frequency sounds was by far the most sensitive of all tests with abnormalities in 71% of all subjects. Whenever any other test was abnormal this test was always abnormal. Interaural time discrimination for low-frequency sounds and evoked potentials were closely related and next most sensitive with abnormalities in approximately 40% of all subjects. Interaural level discrimination and masking level difference were least sensitive with abnormalities in < 10% of subjects. Speech discrimination scores correlated significantly with the masking level differences, as well as with interaural time discrimination for high-frequency sounds. Pontine lesions were found in five of the 16 patients, in whom an objective method for detecting magnetic resonance lesions could be applied. All four with lesions involving the pontine auditory pathway had marked abnormalities in interaural time discrimination and evoked potentials. None of the other 12 had evoked potentials abnormalities. We conclude that neurological tests requiring precise neural timing can reveal behavioural deficits for multiple sclerosis lesions of the auditory pons that are otherwise 'silent'. Of all neurological systems the auditory system at the level of the pons is probably the most sensitive to multiple

  3. 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.

  4. 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.

  5. Reliability of cortical lesion detection on double inversion recovery MRI applying the MAGNIMS-Criteria in multiple sclerosis patients within a 16-months period

    PubMed Central

    Thaler, Christian; Ceyrowski, Tim; Broocks, Gabriel; Treffler, Natascha; Sedlacik, Jan; Stürner, Klarissa; Stellmann, Jan-Patrick; Heesen, Christoph; Fiehler, Jens; Siemonsen, Susanne

    2017-01-01

    Purpose In patients with multiple sclerosis (MS), Double Inversion Recovery (DIR) magnetic resonance imaging (MRI) can be used to identify cortical lesions (CL). We sought to evaluate the reliability of CL detection on DIR longitudinally at multiple subsequent time-points applying the MAGNIMs scoring criteria for CLs. Methods 26 MS patients received a 3T-MRI (Siemens, Skyra) with DIR at 12 time-points (TP) within a 16 months period. Scans were assessed in random order by two different raters. Both raters separately marked all CLs on each scan and total lesion numbers were obtained for each scan-TP and patient. After a retrospective re-evaluation, the number of consensus CLs (conL) was defined as the total number of CLs, which both raters finally agreed on. CLs volumes, relative signal intensities and CLs localizations were determined. Both ratings (conL vs. non-consensus scoring) were compared for further analysis. Results A total number of n = 334 CLs were identified by both raters in 26 MS patients with a first agreement of both raters on 160 out of 334 of the CLs found (κ = 0.48). After the retrospective re-evaluation, consensus agreement increased to 233 out of 334 CL (κ = 0.69). 93.8% of conL were visible in at least 2 consecutive TP. 74.7% of the conL were visible in all 12 consecutive TP. ConL had greater mean lesion volumes and higher mean signal intensities compared to lesions that were only detected by one of the raters (p<0.05). A higher number of CLs in the frontal, parietal, temporal and occipital lobe were identified by both raters than the number of those only identified by one of the raters (p<0.05). Conclusions After a first assessment, slightly less than a half of the CL were considered as reliably detectable on longitudinal DIR images. A retrospective re-evaluation notably increased the consensus agreement. However, this finding is narrowed, considering the fact that retrospective evaluation steps might not be practicable in clinical routine

  6. Reliability of cortical lesion detection on double inversion recovery MRI applying the MAGNIMS-Criteria in multiple sclerosis patients within a 16-months period.

    PubMed

    Faizy, Tobias Djamsched; Thaler, Christian; Ceyrowski, Tim; Broocks, Gabriel; Treffler, Natascha; Sedlacik, Jan; Stürner, Klarissa; Stellmann, Jan-Patrick; Heesen, Christoph; Fiehler, Jens; Siemonsen, Susanne

    2017-01-01

    In patients with multiple sclerosis (MS), Double Inversion Recovery (DIR) magnetic resonance imaging (MRI) can be used to identify cortical lesions (CL). We sought to evaluate the reliability of CL detection on DIR longitudinally at multiple subsequent time-points applying the MAGNIMs scoring criteria for CLs. 26 MS patients received a 3T-MRI (Siemens, Skyra) with DIR at 12 time-points (TP) within a 16 months period. Scans were assessed in random order by two different raters. Both raters separately marked all CLs on each scan and total lesion numbers were obtained for each scan-TP and patient. After a retrospective re-evaluation, the number of consensus CLs (conL) was defined as the total number of CLs, which both raters finally agreed on. CLs volumes, relative signal intensities and CLs localizations were determined. Both ratings (conL vs. non-consensus scoring) were compared for further analysis. A total number of n = 334 CLs were identified by both raters in 26 MS patients with a first agreement of both raters on 160 out of 334 of the CLs found (κ = 0.48). After the retrospective re-evaluation, consensus agreement increased to 233 out of 334 CL (κ = 0.69). 93.8% of conL were visible in at least 2 consecutive TP. 74.7% of the conL were visible in all 12 consecutive TP. ConL had greater mean lesion volumes and higher mean signal intensities compared to lesions that were only detected by one of the raters (p<0.05). A higher number of CLs in the frontal, parietal, temporal and occipital lobe were identified by both raters than the number of those only identified by one of the raters (p<0.05). After a first assessment, slightly less than a half of the CL were considered as reliably detectable on longitudinal DIR images. A retrospective re-evaluation notably increased the consensus agreement. However, this finding is narrowed, considering the fact that retrospective evaluation steps might not be practicable in clinical routine. Lesions that were not reliably

  7. 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.

  8. 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.

  9. An updated histological classification system for multiple sclerosis lesions.

    PubMed

    Kuhlmann, Tanja; Ludwin, Samuel; Prat, Alexandre; Antel, Jack; Brück, Wolfgang; Lassmann, Hans

    2017-01-01

    Multiple sclerosis is a complex and heterogeneous, most likely autoimmune, demyelinating disease of the central nervous system (CNS). Although a number of histological classification systems for CNS lesions have been used by different groups in recent years, no uniform classification exists. In this paper, we propose a simple and unifying classification of MS lesions incorporating many elements of earlier histological systems that aims to provide guidelines for neuropathologists and researchers studying MS lesions to allow for better comparison of different studies performed with MS tissue, and to aid in understanding the pathogenesis of the disease. Based on the presence/absence and distribution of macrophages/microglia (inflammatory activity) and the presence/absence of ongoing demyelination (demyelinating activity), we suggest differentiating between active, mixed active/inactive, and inactive lesions with or without ongoing demyelination. Active lesions are characterized by macrophages/microglia throughout the lesion area, whereas mixed active/inactive lesions have a hypocellular lesion center with macrophages/microglia limited to the lesion border. Inactive lesions are almost completely lacking macrophages/microglia. Active and mixed active/inactive lesions can be further subdivided into lesions with ongoing myelin destruction (demyelinating lesions) and lesions in which the destruction of myelin has ceased, but macrophages are still present (post-demyelinating lesions). This distinction is based on the presence or absence of myelin degradation products within the cytoplasm of macrophages/microglia. For this classification of MS lesions, identification of myelin with histological stains [such as luxol fast blue-PAS] or by immunohistochemistry using antibodies against myelin basic-protein (MBP) or proteolipid-protein (PLP), as well as, detection of macrophages/microglia by, e.g., anti-CD68 is sufficient. Active and demyelinating lesions may be further

  10. Sclerotic bone lesions at abdominal magnetic resonance imaging in children with tuberous sclerosis complex.

    PubMed

    Boronat, Susana; Barber, Ignasi; Pargaonkar, Vivek; Chang, Joshua; Thiele, Elizabeth A

    2016-05-01

    Sclerotic bone lesions are often seen on chest CT in adults with tuberous sclerosis complex. To characterize bone lesions at abdominal MRI in children with tuberous sclerosis complex. This retrospective review included 70 children with tuberous sclerosis complex who had undergone abdominal MRI for renal imaging. An additional longitudinal study was performed in 50 children who had had two or more MRI scans. Abdominal CT (eight children) and radiographs (three children) were reviewed and compared with MRI. A total of 173 sclerotic bone lesions were detected in 51/70 children (73%; 95% confidence interval: 0.61-0.82) chiefly affecting vertebral pedicles. New lesions appeared in 20 children and growth of previous sclerotic bone lesions was documented in 14 children. Sclerotic bone lesions were more frequent in girls and in children with more extensive renal involvement. Sclerotic bone lesions are commonly detected by abdominal MRI in children with tuberous sclerosis complex. They usually affect posterior vertebral elements and their number and size increase with age. As current recommendations for tuberous sclerosis complex surveillance include renal MR performed in childhood, recognition of these lesions is useful.

  11. Putaminal alteration in multiple sclerosis patients with spinal cord lesions.

    PubMed

    Zimmermann, Hilga; Rolfsnes, Hans O; Montag, Swantje; Wilting, Janine; Droby, Amgad; Reuter, Eva; Gawehn, Joachim; Zipp, Frauke; Gröger, Adriane

    2015-10-01

    Typical multiple sclerosis (MS) lesions occur in the brain as well as in the spinal cord. However, two extreme magnetic resonance imaging phenotypes appear occasionally: those with predominantly spinal cord lesions (MS + SL) and those with cerebral lesions and no detectable spinal lesions (MS + CL). We assessed whether morphological differences can be found between these two extreme phenotypes. We examined 19 patients with MS + SL, 18 with MS + CL and 20 controls. All subjects were examined using magnetic resonance imaging, including anatomical and diffusion tensor imaging sequences. Voxel-based morphologic and regions of interest-based analyses and tract-based spatial statistics were performed. Patients also underwent neuropsychological testing. Demographic, clinical and neuropsychological characteristics did not differ between MS + SL and MS + CL patients. Patients with MS + SL showed significantly larger putamen volumes than those with MS + CL which correlated negatively with disability. Compared to controls, only MS + CL revealed clear cortical and deep gray matter atrophy, which correlated with cerebral lesion volume. Additionally, extensive white matter microstructural damage was found only in MS + CL compared to MS + SL and controls in the tract-based spatial statistics. Higher putamen volumes in MS + SL could suggest compensatory mechanisms in this area responsible for motor control. Widely reduced fractional anisotropy values in MS + CL were caused by higher cerebral lesion volume and thus presumably stronger demyelination, which subsequently leads to higher global gray matter atrophy.

  12. Traditional lesion detection aids.

    PubMed

    Neuhaus, K W; Ellwood, R; Lussi, A; Pitts, N B

    2009-01-01

    Lesion detection aids ideally aim at increasing the sensitivity of visual caries detection without trading off too much in terms of specificity. The use of a dental probe (explorer), bitewing radiography and fibre-optic transillumination (FOTI) have long been recommended for this purpose. Today, probing of suspected lesions in the sense of checking the 'stickiness' is regarded as obsolete, since it achieves no gain of sensitivity and might cause irreversible tooth damage. Bitewing radiography helps to detect lesions that are otherwise hidden from visual examination, and it should therefore be applied to a new patient. The diagnostic performance of radiography at approximal and occlusal sites is different, as this relates to the 3-dimensional anatomy of the tooth at these sites. However, treatment decisions have to take more into account than just lesion extension. Bitewing radiography provides additional information for the decision-making process that mainly relies on the visual and clinical findings. FOTI is a quick and inexpensive method which can enhance visual examination of all tooth surfaces. Both radiography and FOTI can improve the sensitivity of caries detection, but require sufficient training and experience to interpret information correctly. Radiography also carries the burden of the risks and legislation associated with using ionizing radiation in a health setting and should be repeated at intervals guided by the individual patient's caries risk. Lesion detection aids can assist in the longitudinal monitoring of the behaviour of initial lesions. Copyright 2009 S. Karger AG, Basel

  13. 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.

  14. Multiple sclerosis lesion segmentation using dictionary learning and sparse coding.

    PubMed

    Weiss, Nick; Rueckert, Daniel; Rao, Anil

    2013-01-01

    The segmentation of lesions in the brain during the development of Multiple Sclerosis is part of the diagnostic assessment for this disease and gives information on its current severity. This laborious process is still carried out in a manual or semiautomatic fashion by clinicians because published automatic approaches have not been universal enough to be widely employed in clinical practice. Thus Multiple Sclerosis lesion segmentation remains an open problem. In this paper we present a new unsupervised approach addressing this problem with dictionary learning and sparse coding methods. We show its general applicability to the problem of lesion segmentation by evaluating our approach on synthetic and clinical image data and comparing it to state-of-the-art methods. Furthermore the potential of using dictionary learning and sparse coding for such segmentation tasks is investigated and various possibilities for further experiments are discussed.

  15. Diffuse systemic sclerosis with bullous lesions without systemic manifestations*

    PubMed Central

    Macedo, Paula Renaux Wanderley Caratta; Mota, Amanda Nascimento Cavalleiro de Macedo; Gripp, Alexandre Carlos; Alves, Maria de Fatima Guimarães Scotelaro; Klumb, Evandro Mendes

    2013-01-01

    Here, we describe an atypical case of systemic sclerosis in its diffuse cutaneous form with acute and rapid progression of the cutaneous condition, without any systemic manifestations and the infrequent formation of bullae, showing the importance of diagnosis and early treatment in such cases. This case also shows that special measures should be taken for bullous cutaneous lesions and ulcerations resulting from serious sclerosis, which are entry points and increase morbidity and risk of death. Other prognostic factors include age, ESR and renal and pulmonary involvement. Capillaroscopies can be useful predictors of greater severity of systemic scleroderma, revealing a greater link with systemic, rather than cutaneous, involvement. PMID:24346886

  16. Spinal cord lesions and disability in Hispanics with multiple sclerosis

    PubMed Central

    Amezcua, L.; Lerner, A.; Ledezma, K.; Conti, D.; Law, M.; Weiner, L.; Langer-Gould, A.

    2013-01-01

    Background Longitudinally extensive spinal cord lesions (LESCLs) are believed to occur predominantly with opticospinal multiple sclerosis (OSMS) and are associated with disability. Objective To describe the prevalence and patterns of spinal cord lesions in Hispanics with multiple sclerosis (MS) and OSMS and their association with disability. Methods Cross-sectional study of 164 patients with complete MRIs. Spinal cord was classified: LESCLs, scattered spinal cord lesions (sSCLs) or no spinal cord lesions (noSCLs). Clinical course was defined as classical MS or OSMS. Risk of disability (Expanded Disability Status Scale ≥4.0) was adjusted for age, disease duration and sex using logistic regression. Results 125/164(73%) MS patients had spinal cord lesions (sSCLs, 57%; LESCLs, 19%) but only 11(7%) had OSMS. LESCLs were associated with disability (p<0.0001), longer disease duration (p<0.0001) and MS (n=21 vs. n=10 OSMS; p<0.0001). LESCLs was associated with the greatest risk to disability (OR 7.3, 95% CIs1.9-26.5; p=0.003; sSCLs OR 2.5, 95% CIs0.9-7.1; p=0.09) compared with noSCLs. Conclusion LESCLs are more common than OSMS and are associated with worse disability even in patients with MS. These results suggest that LESCLs are a more important marker of disability in MS than OSMS and may be an early indicator of more aggressive disease in this population. PMID:23912723

  17. Acute demyelinating lesions with restricted diffusion in multiple sclerosis

    PubMed Central

    Balashov, Konstantin E; Lindzen, Eric

    2013-01-01

    Background and objectives It is widely accepted that typical acute demyelinating lesions in relapsing–remitting multiple sclerosis (RRMS) exhibit vasogenic edema with increased diffusion, as demonstrated by an increased apparent diffusion coefficient on MRI. In contrast, acute ischemic lesions demonstrate cytotoxic edema with restricted diffusion. Recent reports have documented selected cases of acute demyelinating lesions exhibiting restricted diffusion (ADLRD) in MS. We aimed to assess the morphologies, distributions, signal characteristics and changes over time of nine ADLRD. An additional goal was to obtain clinical correlations and relate our findings to all previously published case reports describing ADLRD. Methods A retrospective case series study was performed at two academic centers. MRI characteristics of nine ADLRD found in six RRMS patients were compared with typical active symptomatic contrast-enhancing lesions with increased or normal diffusion in control RRMS patients. Results The average size of ADLRD was not significantly different from typical lesions. A periventricular location and faint signal on T2-weighted images were significantly more common for ADLRD compared with typical lesions. Two patients with ADLRD on initial MRI exhibited new ADLRD on their follow up scans. Conclusion Our results and review of prior published cases suggest that ADLRD represent a new variant of MS lesion. The restricted diffusion that is a characteristic of ADLRD on MRI is a new challenge in the differential diagnosis of stroke in young adults. The pathogenesis of ADLRD remains to be understood. PMID:22523157

  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. Nonrigid registration of multiple sclerosis brain images using lesion inpainting for morphometry or lesion mapping.

    PubMed

    Sdika, Michaël; Pelletier, Daniel

    2009-04-01

    Morphometric studies of medical images often include a nonrigid registration step from a subject to a common reference. The presence of white matter multiple sclerosis lesions will distort and bias the output of the registration. In this article, we present a method to remove this bias by filling such lesions to make the brain look like a healthy brain before the registration. We finally propose a dedicated method to fill the lesions and present numerical results showing that our method outperforms current state of the art method. 2008 Wiley-Liss, Inc.

  20. MALDI imaging mass spectrometry analysis-A new approach for protein mapping in multiple sclerosis brain lesions.

    PubMed

    Maccarrone, Giuseppina; Nischwitz, Sandra; Deininger, Sören-Oliver; Hornung, Joachim; König, Fatima Barbara; Stadelmann, Christine; Turck, Christoph W; Weber, Frank

    2017-03-15

    Multiple sclerosis is a disease of the central nervous system characterized by recurrent inflammatory demyelinating lesions in the early disease stage. Lesion formation and mechanisms leading to lesion remyelination are not fully understood. Matrix Assisted Laser Desorption Ionisation Mass Spectrometry imaging (MALDI-IMS) is a technology which analyses proteins and peptides in tissue, preserves their spatial localization, and generates molecular maps within the tissue section. In a pilot study we employed MALDI imaging mass spectrometry to profile and identify peptides and proteins expressed in normal-appearing white matter, grey matter and multiple sclerosis brain lesions with different extents of remyelination. The unsupervised clustering analysis of the mass spectra generated images which reflected the tissue section morphology in luxol fast blue stain and in myelin basic protein immunohistochemistry. Lesions with low remyelination extent were defined by compounds with molecular weight smaller than 5300Da, while more completely remyelinated lesions showed compounds with molecular weights greater than 15,200Da. An in-depth analysis of the mass spectra enabled the detection of cortical lesions which were not seen by routine luxol fast blue histology. An ion mass, mainly distributed at the rim of multiple sclerosis lesions, was identified by liquid chromatography and tandem mass spectrometry as thymosin beta-4, a protein known to be involved in cell migration and in restorative processes. The ion mass of thymosin beta-4 was profiled by MALDI imaging mass spectrometry in brain slides of 12 multiple sclerosis patients and validated by immunohistochemical analysis. In summary, our results demonstrate the ability of the MALDI-IMS technology to map proteins within the brain parenchyma and multiple sclerosis lesions and to identify potential markers involved in multiple sclerosis pathogenesis and/or remyelination. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Extensive Acute Axonal Damage in Pediatric Multiple Sclerosis Lesions

    PubMed Central

    Pfeifenbring, Sabine; Bunyan, Reem F.; Metz, Imke; Röver, Christian; Huppke, Peter; Gärtner, Jutta; Lucchinetti, Claudia F.; Brück, Wolfgang

    2015-01-01

    Objective Axonal damage occurs early in multiple sclerosis (MS) and contributes to the degree of clinical disability. Children with MS more often show disabling and polyfocal neurological symptoms at disease onset than adults with MS. Thus, axonal damage may differ between pediatric and adult MS patients. Methods We analyzed axonal pathology in archival brain biopsy and autopsy samples from 19 children with early MS. Lesions were classified according to demyelinating activity and presence of remyelination. Axonal density and extent of acute axonal damage were assessed using Bielschowsky silver impregnation and immunohistochemistry for amyloid precursor protein (APP), respectively. Axonal injury was correlated with the inflammatory infiltrate as well as clinical characteristics. Results were compared with data from adult MS patients. Results Acute axonal damage was most extensive in early active demyelinating (EA) lesions of pediatric patients and correlated positively with the Expanded Disability Status Scale at attack leading to biopsy/autopsy. Comparison with 12 adult patients showed a 50% increase in the extent of acute axonal damage in EA lesions from children compared to adults, with the highest number of APP-positive spheroids found prior to puberty. The extent of acute axonal damage correlated positively with the number of lesional macrophages. Axonal density was reduced in pediatric lesions irrespective of the demyelinating activity or the presence of remyelination. Axonal reduction was similar between children and adults. Interpretation Our results provide evidence for more pronounced acute axonal damage in inflammatory demyelinating lesions from children compared to adults. PMID:25612167

  2. Spinal cord lesions and disability in Hispanics with multiple sclerosis.

    PubMed

    Amezcua, L; Lerner, A; Ledezma, K; Conti, D; Law, M; Weiner, L; Langer-Gould, A

    2013-11-01

    Longitudinally extensive spinal cord lesions (LESCLs) are believed to occur predominantly with opticospinal multiple sclerosis (OSMS) and are associated with disability. The purpose of this study is to describe the prevalence and patterns of spinal cord lesions in Hispanics with multiple sclerosis (MS) and OSMS and their association with disability. A cross-sectional study of 164 patients with complete MRIs was used. In each case the spinal cord was classified: LESCLs, scattered spinal cord lesions (sSCLs) or no spinal cord lesions (noSCLs). Clinical course was defined as classical MS or OSMS. Risk of disability (Expanded Disability Status Scale ≥4.0) was adjusted for age, disease duration and sex using logistic regression. A total of 125/164 (73 %) MS patients had spinal cord lesions (sSCLs, 57 %; LESCLs, 19 %), but only 11 (7 %) had OSMS. LESCLs were associated with disability (p < 0.0001), longer disease duration (p < 0.0001) and MS (n = 21 vs. n = 10 OSMS; p < 0.0001). LESCLs were also associated with the greatest risk to disability (OR 7.3, 95 % CIs 1.9-26.5; p = 0.003; sSCLs OR 2.5, 95 % CIs 0.9-7.1; p = 0.09) compared with noSCLs. LESCLs are more common than OSMS and are associated with worse disability even in patients with MS. These results suggest that LESCLs are a more important marker of disability in MS than OSMS and may be an early indicator of more aggressive disease in this population.

  3. 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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Pathologic Heterogeneity Persists in Early Active Multiple Sclerosis Lesions

    PubMed Central

    Metz, Imke; Weigand, Stephen D; Popescu, Bogdan F G; Frischer, Josa M; Parisi, Joseph E; Guo, Yong; Lassmann, Hans; Brück, Wolfgang; Lucchinetti, Claudia F.

    2014-01-01

    Objective Multiple sclerosis (MS) lesions demonstrate immunopathological heterogeneity in patterns of demyelination. Previous cross-sectional studies reported immunopatterns of demyelination were identical among multiple active demyelinating lesions from the same individual, but differed between individuals, leading to the hypothesis of intraindividual pathological homogeneity and interindividual heterogeneity. Other groups suggested a time-dependent heterogeneity of lesions. The objective of our present study was to analyze tissue samples collected longitudinally to determine whether patterns of demyelination persist over time within a given patient. Methods Archival tissue samples derived from patients with pathologically confirmed CNS inflammatory demyelinating disease who had undergone either diagnostic serial biopsy or biopsy followed by autopsy, were analyzed immunohistochemically. Inclusion criteria was the presence of early active demyelinating lesions - required for immunopattern classification - obtained from the same patient at two or more time points. Results Among 1321 surgical biopsies consistent with MS, 22 cases met study inclusion criteria. Twenty-one patients (95%) showed a persistence of immunopathological patterns in tissue sampled from different time points. This persistence was demonstrated for all major patterns of demyelination. A single patient showed features suggestive of both pattern II and pattern III on biopsy, but only pattern II among all active lesions examined at autopsy. Interpretation These findings continue to support the concept of patient-dependent immunopathological heterogeneity in early MS and suggest that the mechanisms and targets of tissue injury may differ among patient subgroups. These observations have potentially significant implications for individualized therapeutic approaches. PMID:24771535

  5. Characteristics of lesional and extra-lesional cortical grey matter in relapsing-remitting and secondary progressive multiple sclerosis: A magnetisation transfer and diffusion tensor imaging study.

    PubMed

    Yaldizli, Özgür; Pardini, Matteo; Sethi, Varun; Muhlert, Nils; Liu, Zheng; Tozer, Daniel J; Samson, Rebecca S; Wheeler-Kingshott, Claudia Am; Yousry, Tarek A; Miller, David H; Chard, Declan T

    2016-02-01

    In multiple sclerosis (MS), diffusion tensor and magnetisation transfer imaging are both abnormal in lesional and extra-lesional cortical grey matter, but differences between clinical subtypes and associations with clinical outcomes have only been partly assessed. To compare mean diffusivity, fractional anisotropy and magnetisation transfer ratio (MTR) in cortical grey matter lesions (detected using phase-sensitive inversion recovery (PSIR) imaging) and extra-lesional cortical grey matter, and assess associations with disability in relapse-onset MS. Seventy-two people with MS (46 relapsing-remitting (RR), 26 secondary progressive (SP)) and 36 healthy controls were included in this study. MTR, mean diffusivity and fractional anisotropy were measured in lesional and extra-lesional cortical grey matter. Mean fractional anisotropy was higher and MTR lower in lesional compared with extra-lesional cortical grey matter. In extra-lesional cortical grey matter mean fractional anisotropy and MTR were lower, and mean diffusivity was higher in the MS group compared with controls. Mean MTR was lower and mean diffusivity was higher in lesional and extra-lesional cortical grey matter in SPMS when compared with RRMS. These differences were independent of disease duration. In multivariate analyses, MTR in extra-lesional more so than lesional cortical grey matter was associated with disability. Magnetic resonance abnormalities in lesional and extra-lesional cortical grey matter are greater in SPMS than RRMS. Changes in extra-lesional compared with lesional cortical grey matter are more consistently associated with disability. © The Author(s), 2015.

  6. 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

  7. 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.

  8. Magnetic resonance monitoring of lesion evolution in multiple sclerosis

    PubMed Central

    Auger, Cristina; Alonso, Juli

    2013-01-01

    Disease activity in multiple sclerosis (MS) is strongly linked to the formation of new lesions, which involves a complex sequence of inflammatory, degenerative, and reparative processes. Conventional magnetic resonance imaging (MRI) techniques, such as T2-weighted and gadolinium-enhanced T1-weighted sequences, are highly sensitive in demonstrating the spatial and temporal dissemination of demyelinating plaques in the brain and spinal cord. Hence, these techniques can provide quantitative assessment of disease activity in patients with MS, and they are commonly used in monitoring treatment efficacy in clinical trials and in individual cases. However, the correlation between conventional MRI measures of disease activity and the clinical manifestations of the disease, particularly irreversible disability, is weak. This has been explained by a process of exhaustion of both structural and functional redundancies that increasingly prevents repair and recovery, and by the fact that these imaging techniques do not suffice to explain the entire spectrum of the disease process and lesion development. Nonconventional MRI techniques, such as magnetization transfer imaging, diffusion-weighted imaging, and proton magnetic resonance spectroscopy, which can selectively measure the more destructive aspects of MS pathology and monitor the reparative mechanisms of this disease, are increasingly being used for serial analysis of new lesion formation and provide a better approximation of the pathological substrate of MS plaques. These nonconventional MRI-based measures better assess the serial changes in newly forming lesions and improve our understanding of the relationship between the damaging and reparative mechanisms that occur in MS. PMID:23997815

  9. Longitudinal multiple sclerosis lesion segmentation: Resource and challenge.

    PubMed

    Carass, Aaron; Roy, Snehashis; Jog, Amod; Cuzzocreo, Jennifer L; Magrath, Elizabeth; Gherman, Adrian; Button, Julia; Nguyen, James; Prados, Ferran; Sudre, Carole H; Jorge Cardoso, Manuel; Cawley, Niamh; Ciccarelli, Olga; Wheeler-Kingshott, Claudia A M; Ourselin, Sébastien; Catanese, Laurence; Deshpande, Hrishikesh; Maurel, Pierre; Commowick, Olivier; Barillot, Christian; Tomas-Fernandez, Xavier; Warfield, Simon K; Vaidya, Suthirth; Chunduru, Abhijith; Muthuganapathy, Ramanathan; Krishnamurthi, Ganapathy; Jesson, Andrew; Arbel, Tal; Maier, Oskar; Handels, Heinz; Iheme, Leonardo O; Unay, Devrim; Jain, Saurabh; Sima, Diana M; Smeets, Dirk; Ghafoorian, Mohsen; Platel, Bram; Birenbaum, Ariel; Greenspan, Hayit; Bazin, Pierre-Louis; Calabresi, Peter A; Crainiceanu, Ciprian M; Ellingsen, Lotta M; Reich, Daniel S; Prince, Jerry L; Pham, Dzung L

    2017-03-01

    In conjunction with the ISBI 2015 conference, we organized a longitudinal lesion segmentation challenge providing training and test data to registered participants. The training data consisted of five subjects with a mean of 4.4 time-points, and test data of fourteen subjects with a mean of 4.4 time-points. All 82 data sets had the white matter lesions associated with multiple sclerosis delineated by two human expert raters. Eleven teams submitted results using state-of-the-art lesion segmentation algorithms to the challenge, with ten teams presenting their results at the conference. We present a quantitative evaluation comparing the consistency of the two raters as well as exploring the performance of the eleven submitted results in addition to three other lesion segmentation algorithms. The challenge presented three unique opportunities: (1) the sharing of a rich data set; (2) collaboration and comparison of the various avenues of research being pursued in the community; and (3) a review and refinement of the evaluation metrics currently in use. We report on the performance of the challenge participants, as well as the construction and evaluation of a consensus delineation. The image data and manual delineations will continue to be available for download, through an evaluation website(2) as a resource for future researchers in the area. This data resource provides a platform to compare existing methods in a fair and consistent manner to each other and multiple manual raters. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Lesion detectability in digital radiography

    NASA Astrophysics Data System (ADS)

    Gagne, Robert M.; Boswell, Jonathan S.; Myers, Kyle J.; Peter, Guillaume

    2001-06-01

    The usefulness of Fourier-based measures of imaging performance has come into question for the evaluation of digital imaging systems. Figures of merit such as detective quantum efficiency are relevant for linear, shift-invariant systems with stationary noise. However, no digital imaging system is shift invariant, and realistic images do not satisfy the stationarity condition. Our methods for task- based evaluation of imaging systems, based on lesion detectability, do not require such assumptions. We have computed the performance of Hotelling and nonprewhitening matched-filter observers for the task of lesion detection in digital radiography.

  11. Lesion heterogeneity on high-field susceptibility MRI is associated with multiple sclerosis severity

    PubMed Central

    Harrison, Daniel M.; Li, Xu; Liu, Hongjun; Jones, Craig K.; Caffo, Brian; Calabresi, Peter A.; van Zijl, Peter

    2016-01-01

    Background and Purpose Susceptibility MRI contrast variations reflect alterations in brain iron and myelin content- making this imaging tool relevant to studies of multiple sclerosis lesion heterogeneity. In this study we aimed to characterize the relationship of high-field, susceptibility contrasts in multiple sclerosis lesions to clinical outcomes. Materials and Methods Twenty-four subjects with multiple sclerosis underwent 7-tesla MRI of the brain, disability exams, and a fatigue inventory. R2*, frequency, and relative susceptibility (from quantitative susceptibility mapping) were analyzed in 306 white matter lesions. Results Most lesions were hypointense on R2* (88% without a rim, 5% with). Lesions that were hyperintense on quantitative susceptibility mapping were more frequent in relapsing-remitting than progressive multiple sclerosis (54% vs. 35%, p = 0.018). Hyperintense lesion rims on quantitative susceptibility maps were more common in progressive multiple sclerosis and higher levels of disability and fatigue. Mean lesion R2* was inversely related to disability and fatigue and significantly reduced in progressive multiple sclerosis. Relative susceptibility was lower lesions in progressive multiple sclerosis (median -0.018 ppm, range -0.070 – 0.022) than relapsing-remitting (median -0.010 ppm, range -0.062 – 0.052, p = 0.003). Conclusion A progressive clinical phenotype, greater disability, and fatigue were associated with lower R2* and relative susceptibility values (suggestive of low iron due to oligodendrocyte loss) and rimmed lesions (suggestive of chronic inflammation) in this multiple sclerosis cohort. Lesion heterogeneity on susceptibility MRI may help explain disability in multiple sclerosis and provide a window into the processes of demyelination, oligodendrocyte loss, and chronic lesion inflammation. PMID:26939635

  12. OASIS is Automated Statistical Inference for Segmentation, with applications to multiple sclerosis lesion segmentation in MRI.

    PubMed

    Sweeney, Elizabeth M; Shinohara, Russell T; Shiee, Navid; Mateen, Farrah J; Chudgar, Avni A; Cuzzocreo, Jennifer L; Calabresi, Peter A; Pham, Dzung L; Reich, Daniel S; Crainiceanu, Ciprian M

    2013-01-01

    Magnetic resonance imaging (MRI) can be used to detect lesions in the brains of multiple sclerosis (MS) patients and is essential for diagnosing the disease and monitoring its progression. In practice, lesion load is often quantified by either manual or semi-automated segmentation of MRI, which is time-consuming, costly, and associated with large inter- and intra-observer variability. We propose OASIS is Automated Statistical Inference for Segmentation (OASIS), an automated statistical method for segmenting MS lesions in MRI studies. We use logistic regression models incorporating multiple MRI modalities to estimate voxel-level probabilities of lesion presence. Intensity-normalized T1-weighted, T2-weighted, fluid-attenuated inversion recovery and proton density volumes from 131 MRI studies (98 MS subjects, 33 healthy subjects) with manual lesion segmentations were used to train and validate our model. Within this set, OASIS detected lesions with a partial area under the receiver operating characteristic curve for clinically relevant false positive rates of 1% and below of 0.59% (95% CI; [0.50%, 0.67%]) at the voxel level. An experienced MS neuroradiologist compared these segmentations to those produced by LesionTOADS, an image segmentation software that provides segmentation of both lesions and normal brain structures. For lesions, OASIS out-performed LesionTOADS in 74% (95% CI: [65%, 82%]) of cases for the 98 MS subjects. To further validate the method, we applied OASIS to 169 MRI studies acquired at a separate center. The neuroradiologist again compared the OASIS segmentations to those from LesionTOADS. For lesions, OASIS ranked higher than LesionTOADS in 77% (95% CI: [71%, 83%]) of cases. For a randomly selected subset of 50 of these studies, one additional radiologist and one neurologist also scored the images. Within this set, the neuroradiologist ranked OASIS higher than LesionTOADS in 76% (95% CI: [64%, 88%]) of cases, the neurologist 66% (95% CI: [52%, 78

  13. Iron Is a Sensitive Biomarker for Inflammation in Multiple Sclerosis Lesions

    PubMed Central

    Mehta, Veela; Pei, Wei; Yang, Grant; Li, Suyang; Swamy, Eashwar; Boster, Aaron; Schmalbrock, Petra; Pitt, David

    2013-01-01

    MRI phase imaging in multiple sclerosis (MS) patients and in autopsy tissue have demonstrated the presence of iron depositions in white matter lesions. The accumulation of iron in some but not all lesions suggests a specific, potentially disease-relevant process, however; its pathophysiological significance remains unknown. Here, we explore the role of lesional iron in multiple sclerosis using multiple approaches: immunohistochemical examination of autoptic MS tissue, an in vitro model of iron-uptake in human cultured macrophages and ultra-highfield phase imaging of highly active and of secondary progressive MS patients. Using Perls' stain and immunohistochemistry, iron was detected in MS tissue sections predominantly in non-phagocytosing macrophages/microglia at the edge of established, demyelinated lesions. Moreover, iron-containing macrophages but not myelin-laden macrophages expressed markers of proinflammatory (M1) polarization. Similarly, in human macrophage cultures, iron was preferentially taken up by non-phagocytosing, M1-polarized macrophages and induced M1 (super) polarization. Iron uptake was minimal in myelin-laden macrophages and active myelin phagocytosis led to depletion of intracellular iron. Finally, we demonstrated in MS patients using GRE phase imaging with ultra-highfield MRI that phase hypointense lesions were significantly more prevalent in patients with active relapsing than with secondary progressive MS. Taken together, our data provide a basis to interpret iron-sensitive GRE phase imaging in MS patients: iron is present in non-phagocytosing, M1-polarized microglia/macrophages at the rim of chronic active white matter demyelinating lesions. Phase imaging may therefore visualize specific, chronic proinflammatory activity in established MS lesions and thus provide important clinical information on disease status and treatment efficacy in MS patients. PMID:23516409

  14. Diffusivity in multiple sclerosis lesions: At the cutting edge?

    PubMed

    Klistorner, Alexander; Wang, Chenyu; Fofanova, Vera; Barnett, Michael H; Yiannikas, Con; Parratt, John; You, Yuyi; Graham, Stuart L

    2016-01-01

    Radial Diffusivity (RD) has been suggested as a promising biomarker associated with the level of myelination in MS lesions. However, the level of RD within the lesion is affected not only by loss of myelin sheaths, but also by the degree of tissue destruction. This may lead to exaggeration of diffusivity measures, potentially masking the effect of remyelination. To test the hypothesis that the T2 hyperintense lesion edge that extends beyond the T1 hypointense lesion core is less affected by tissue loss, and therefore a more appropriate target for imaging biomarker development targeting de- and re-myelination. Pre- and post-gadolinium (Gd) enhanced T1, T2 and DTI images were acquired from 75 consecutive RRMS patients. The optic radiation (OR) was identified in individual patients using a template-based method. T2 lesions were segmented into T1-hypointense and T1-isointense areas and lesion masks intersected with the OR. Average Radial, Axial and Mean diffusivity (RD, AD and MD) and fractional anisotropy (FA) were calculated for lesions of the entire brain and the OR. In addition, Gd enhancing lesions were excluded from the analysis. 86% of chronic T2 lesions demonstrated hypointense areas on T1-weighted images, which typically occupied the central part of each T2 lesion, taking about 40% of lesional volume. The T1-isointense component of the T2 lesion was most commonly seen as a peripheral ring of relatively constant thickness ("T2-rim"). While changes of diffusivity between adjacent normal appearing white matter and the "T2-rim" demonstrated a disproportionally high elevation of RD compare to AD, the increase of water diffusion was largely isointense between the "T2-rim" and T1-hypointense parts of the lesion. Distinct patterns of diffusivity within the central and peripheral components of MS lesions suggest that axonal loss dominates in the T1 hypointense core. The effects of de/remyelination may be more readily detected in the "T2-rim", where there is relative

  15. 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.

  16. Effects of multiple sclerosis brainstem lesions on sound lateralization and brainstem auditory evoked potentials.

    PubMed

    Levine, R A; Gardner, J C; Fullerton, B C; Stufflebeam, S M; Carlisle, E W; Furst, M; Rosen, B R; Kiang, N Y

    1993-06-01

    Magnetic resonance (MR) imaging, brainstem auditory evoked potentials (BAEPs), and tests of interaural time and level discrimination were performed on sixteen subjects with multiple sclerosis (MS). Objective criteria were used to define MR lesions. Of the eleven subjects in whom no pontine lesions were detected and the one subject who had pontine lesions that did not encroach upon the auditory pathways, all had normal BAEPs and interaural level discrimination, although a few had abnormal interaural time discrimination. Of four subjects with lesions involving the pontine auditory pathway, all had both abnormal BAEPs and abnormal interaural time discrimination; one also had abnormal interaural level discrimination. Analysis of the data suggest the following: waves I and II are generated peripheral to the middle of the ventral acoustic stria (VAS); wave III is generated ipsilaterally in the region of the rostral VAS, caudal superior olivary complex (SOC) and trapezoid body (TB); and waves V and L are generated contralaterally, rostral to the SOC-TB. The region of the ipsilateral rostral SOC-TB is implicated as part of the pathway involved in the generation of waves V and L. Interaural time discrimination of both high and low frequency stimuli were affected by all brainstem lesions that encroached on auditory pathways. A unilateral lesion in the region of the LL affected interaural time discrimination for low-frequency stimuli less severely than bilateral lesions of the LL or a unilateral lesion of the VAS. The only interaural level discrimination abnormality occurred for a subject with a unilateral lesion involving the entire rostral VAS. It appears that detailed analysis of lesion locations coupled with electrophysiological and psychophysical data holds promise for testing hypotheses concerning the function of various human auditory brainstem structures.

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

    PubMed

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

    2016-05-01

    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. 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. 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. DIR-detectable GM lesions and GM atrophy do not significantly overlap in the brain but, when they do, they independently contribute to clinical disability. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  18. 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.

  19. Astrocytes within multiple sclerosis lesions upregulate sodium channel Nav1.5.

    PubMed

    Black, Joel A; Newcombe, Jia; Waxman, Stephen G

    2010-03-01

    Astrocytes are prominent participants in the response of the central nervous system to injury, including neuroinflammatory insults. Rodent astrocytes in vitro have been shown to express voltage-gated sodium channels in a dynamic manner, with a switch in expression of tetrodotoxin-sensitive to tetrodotoxin-resistant channels in reactive astrocytes. However, the expression of sodium channels in human astrocytes has not been studied, and it is not known whether there are changes in the expression of sodium channels in reactive astrocytes of the human central nervous system. Here, we demonstrate a focal and robust upregulation of sodium channel Nav1.5 in reactive astrocytes at the borders of, and within, active and chronic multiple sclerosis lesions. Nav1.5 was only detectable at very low levels in astrocytes within multiple sclerosis macroscopically normal-appearing white matter or in normal control brain. Nav1.1, Nav1.2, Nav1.3 and Nav1.6 showed little or no expression in astrocytes within normal control tissue and limited upregulation in active multiple sclerosis lesions. Nav1.5 was also expressed at high levels in astrocytes in tissue surrounding new and old cerebrovascular accidents and brain tumours. These results demonstrate the expression of Nav1.5 in human astrocytes and show that Nav1.5 expression is dynamic in these cells. Our observations suggest that the upregulated expression of Nav1.5 in astrocytes may provide a compensatory mechanism, which supports sodium/potassium pump-dependent ionic homoeostasis in areas of central nervous system injury.

  20. 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.

  1. 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.

  2. Brain microbiota disruption within inflammatory demyelinating lesions in multiple sclerosis

    PubMed Central

    Branton, W. G.; Lu, J. Q.; Surette, M. G.; Holt, R. A.; Lind, J.; Laman, J. D.; Power, C.

    2016-01-01

    Microbial communities reside in healthy tissues but are often disrupted during disease. Bacterial genomes and proteins are detected in brains from humans, nonhuman primates, rodents and other species in the absence of neurological disease. We investigated the composition and abundance of microbiota in frozen and fixed autopsied brain samples from patients with multiple sclerosis (MS) and age- and sex-matched nonMS patients as controls, using neuropathological, molecular and bioinformatics tools. 16s rRNA sequencing revealed Proteobacteria to be the dominant phylum with restricted diversity in cerebral white matter (WM) from MS compared to nonMS patients. Both clinical groups displayed 1,200–1,400 bacterial genomes/cm3 and low bacterial rRNA:rDNA ratios in WM. RNAseq analyses showed a predominance of Proteobacteria in progressive MS patients’ WM, associated with increased inflammatory gene expression, relative to a broader range of bacterial phyla in relapsing-remitting MS patients’ WM. Although bacterial peptidoglycan (PGN) and RNA polymerase beta subunit immunoreactivities were observed in all patients, PGN immunodetection was correlated with demyelination and neuroinflammation in MS brains. Principal component analysis revealed that demyelination, PGN and inflammatory gene expression accounted for 86% of the observed variance. Thus, inflammatory demyelination is linked to an organ-specific dysbiosis in MS that could contribute to underlying disease mechanisms. PMID:27892518

  3. Axonal loss of retinal neurons in multiple sclerosis associated with optic radiation lesions.

    PubMed

    Klistorner, Alexander; Sriram, Prima; Vootakuru, Nikitha; Wang, Chenyu; Barnett, Michael H; Garrick, Raymond; Parratt, John; Levin, Netta; Raz, Noa; Van der Walt, Anneke; Masters, Lynette; Graham, Stuart L; Yiannikas, Con

    2014-06-17

    To investigate the potential links between thinning of retinal ganglion cell axons in eyes of patients with multiple sclerosis (MS) without past optic neuritis (ON) and MS-related inflammatory damage of the posterior visual pathway. Temporal retinal nerve fiber layer (tRNFL) thickness was analyzed in eyes with no history of ON (NON) from 53 patients with relapsing-remitting MS. Fifty normal age- and sex-matched controls were examined with optical coherence tomography. Low-contrast visual acuity charts were used for functional assessment of vision. The optic tract (OT) and optic radiation (OR) were identified using probabilistic tractography, and volume of T2 fluid-attenuated inversion recovery lesions and diffusion tensor imaging (DTI) indices were measured within both structures. Cross-sectional diameter of the OT was also calculated. tRNFL thickness was significantly reduced in NON eyes and was associated with reduced low-contrast visual acuity. Lesions within the OR were detected in the majority of patients. There was a significant correlation between thinning of the tRNFL and OR lesion volume (adjusted for non-OR lesion volume, age, sex, and disease duration). tRNFL thickness also correlated with OR DTI indices. No OT lesions were identified in any of the patients and no relationship between retinal nerve fiber layer loss and potential markers of OT lesions was found. The results demonstrate a strong tract-specific association between loss of tRNFL fibers and MS-related inflammation within OR. © 2014 American Academy of Neurology.

  4. Axonal loss of retinal neurons in multiple sclerosis associated with optic radiation lesions

    PubMed Central

    Sriram, Prima; Vootakuru, Nikitha; Wang, Chenyu; Barnett, Michael H.; Garrick, Raymond; Parratt, John; Levin, Netta; Raz, Noa; Van der Walt, Anneke; Masters, Lynette; Graham, Stuart L.; Yiannikas, Con

    2014-01-01

    Objective: To investigate the potential links between thinning of retinal ganglion cell axons in eyes of patients with multiple sclerosis (MS) without past optic neuritis (ON) and MS-related inflammatory damage of the posterior visual pathway. Methods: Temporal retinal nerve fiber layer (tRNFL) thickness was analyzed in eyes with no history of ON (NON) from 53 patients with relapsing-remitting MS. Fifty normal age- and sex-matched controls were examined with optical coherence tomography. Low-contrast visual acuity charts were used for functional assessment of vision. The optic tract (OT) and optic radiation (OR) were identified using probabilistic tractography, and volume of T2 fluid-attenuated inversion recovery lesions and diffusion tensor imaging (DTI) indices were measured within both structures. Cross-sectional diameter of the OT was also calculated. Results: tRNFL thickness was significantly reduced in NON eyes and was associated with reduced low-contrast visual acuity. Lesions within the OR were detected in the majority of patients. There was a significant correlation between thinning of the tRNFL and OR lesion volume (adjusted for non-OR lesion volume, age, sex, and disease duration). tRNFL thickness also correlated with OR DTI indices. No OT lesions were identified in any of the patients and no relationship between retinal nerve fiber layer loss and potential markers of OT lesions was found. Conclusion: The results demonstrate a strong tract-specific association between loss of tRNFL fibers and MS-related inflammation within OR. PMID:24838786

  5. 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

  6. 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.

  7. 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

  8. Characterization of Microcirculation in Multiple Sclerosis Lesions by Dynamic Texture Parameter Analysis (DTPA)

    PubMed Central

    Heldner, Mirjam Rahel; Kellner-Weldon, Frauke; Kottke, Raimund; Ozdoba, Christoph; Weisstanner, Christian; Kamm, Christian Philipp; Wiest, Roland

    2013-01-01

    Objective Texture analysis is an alternative method to quantitatively assess MR-images. In this study, we introduce dynamic texture parameter analysis (DTPA), a novel technique to investigate the temporal evolution of texture parameters using dynamic susceptibility contrast enhanced (DSCE) imaging. Here, we aim to introduce the method and its application on enhancing lesions (EL), non-enhancing lesions (NEL) and normal appearing white matter (NAWM) in multiple sclerosis (MS). Methods We investigated 18 patients with MS and clinical isolated syndrome (CIS), according to the 2010 McDonald's criteria using DSCE imaging at different field strengths (1.5 and 3 Tesla). Tissues of interest (TOIs) were defined within 27 EL, 29 NEL and 37 NAWM areas after normalization and eight histogram-based texture parameter maps (TPMs) were computed. TPMs quantify the heterogeneity of the TOI. For every TOI, the average, variance, skewness, kurtosis and variance-of-the-variance statistical parameters were calculated. These TOI parameters were further analyzed using one-way ANOVA followed by multiple Wilcoxon sum rank testing corrected for multiple comparisons. Results Tissue- and time-dependent differences were observed in the dynamics of computed texture parameters. Sixteen parameters discriminated between EL, NEL and NAWM (pAVG = 0.0005). Significant differences in the DTPA texture maps were found during inflow (52 parameters), outflow (40 parameters) and reperfusion (62 parameters). The strongest discriminators among the TPMs were observed in the variance-related parameters, while skewness and kurtosis TPMs were in general less sensitive to detect differences between the tissues. Conclusion DTPA of DSCE image time series revealed characteristic time responses for ELs, NELs and NAWM. This may be further used for a refined quantitative grading of MS lesions during their evolution from acute to chronic state. DTPA discriminates lesions beyond features of enhancement or T2

  9. Characterization of microcirculation in multiple sclerosis lesions by dynamic texture parameter analysis (DTPA).

    PubMed

    Verma, Rajeev Kumar; Slotboom, Johannes; Heldner, Mirjam Rachel; Heldner, Mirjam Rahel; Kellner-Weldon, Frauke; Kottke, Raimund; Ozdoba, Christoph; Weisstanner, Christian; Kamm, Christian Philipp; Wiest, Roland

    2013-01-01

    Texture analysis is an alternative method to quantitatively assess MR-images. In this study, we introduce dynamic texture parameter analysis (DTPA), a novel technique to investigate the temporal evolution of texture parameters using dynamic susceptibility contrast enhanced (DSCE) imaging. Here, we aim to introduce the method and its application on enhancing lesions (EL), non-enhancing lesions (NEL) and normal appearing white matter (NAWM) in multiple sclerosis (MS). We investigated 18 patients with MS and clinical isolated syndrome (CIS), according to the 2010 McDonald's criteria using DSCE imaging at different field strengths (1.5 and 3 Tesla). Tissues of interest (TOIs) were defined within 27 EL, 29 NEL and 37 NAWM areas after normalization and eight histogram-based texture parameter maps (TPMs) were computed. TPMs quantify the heterogeneity of the TOI. For every TOI, the average, variance, skewness, kurtosis and variance-of-the-variance statistical parameters were calculated. These TOI parameters were further analyzed using one-way ANOVA followed by multiple Wilcoxon sum rank testing corrected for multiple comparisons. Tissue- and time-dependent differences were observed in the dynamics of computed texture parameters. Sixteen parameters discriminated between EL, NEL and NAWM (pAVG = 0.0005). Significant differences in the DTPA texture maps were found during inflow (52 parameters), outflow (40 parameters) and reperfusion (62 parameters). The strongest discriminators among the TPMs were observed in the variance-related parameters, while skewness and kurtosis TPMs were in general less sensitive to detect differences between the tissues. DTPA of DSCE image time series revealed characteristic time responses for ELs, NELs and NAWM. This may be further used for a refined quantitative grading of MS lesions during their evolution from acute to chronic state. DTPA discriminates lesions beyond features of enhancement or T2-hypersignal, on a numeric scale allowing for a

  10. Detailing intra-lesional venous lumen shrinking in multiple sclerosis investigated by sFLAIR MRI at 7-T.

    PubMed

    Müller, Katharina; Kuchling, Joseph; Dörr, Jan; Harms, Lutz; Ruprecht, Klemens; Niendorf, Thoralf; Wuerfel, Jens; Paul, Friedemann; Sinnecker, Tim

    2014-10-01

    Intra-lesional venous lumen shrinking detectable by MRI was suggested as an in vivo marker of inflammation in multiple sclerosis (MS). In our study mean diameters of pre-, post- and intra-lesional venous sections were determined in 49 patients with MS or clinically isolated syndrome (CIS) using a pixel-wise analysis on susceptibility-weighted fluid-attenuated inversion recovery (sFLAIR) images and T2*-weighted (T2*w) imaging at 7 Tesla (T). We observed post-to-intra-lesional venous lumen shrinking on T2*w images (p = 0.036) in an analysis of 338 venous sections. Pre-to-intra-lesional venous lumen reduction was only detectable in less than 50% of lesions and failed statistical significance when analysing T2*w (p = 0.325) and sFLAIR images (p = 0.258). In conclusion, thinning of intra-lesional veins in MS is--if detectable at all--probably less severe than previously reported, and affects only a minority of MS lesions.

  11. Thalamic lesions in multiple sclerosis by 7T MRI: clinical implications and relationship to cortical pathology

    PubMed Central

    Harrison, Daniel M.; Oh, Jiwon; Roy, Snehashis; Wood, Emily T.; Whetstone, Anna; Seigo, Michaela A.; Jones, Craig K.; Pham, Dzung; van Zijl, Peter; Reich, Daniel S.; Calabresi, Peter A.

    2014-01-01

    Objective Pathology in both cortex and deep gray matter contribute to disability in multiple sclerosis (MS). We used the increased signal-to-noise ratio of 7-tesla (7T) MRI to visualize small lesions within the thalamus and to relate this to clinical information and cortical lesions. Methods 7T MRI scans were obtained on 34 MS cases and 15 healthy volunteers. Thalamic lesion number and volume were related to demographic data, clinical disability measures, and lesions in cortical gray matter. Results Thalamic lesions were found in 24/34 of MS cases. Two lesion subtypes were noted: discrete, ovoid lesions, and more diffuse lesional areas lining the periventricular surface. The number of thalamic lesions was greater in progressive MS compared to relapsing remitting (mean ± SD, 10.7 ± 0.7 vs. 3.0 ± 0.7, respectively, p < 0.001). Thalamic lesion burden (count and volume) correlated with EDSS score and measures of cortical lesion burden, but not with white matter lesion burden or white matter volume. Conclusions 7T MRI allows identification of thalamic lesions in MS, which are associated with disability, progressive disease, and cortical lesions. Thalamic lesion analysis may be a simpler, more rapid estimate of overall gray matter lesion burden in MS. PMID:25583851

  12. Isolation of Astrocytes Displaying Myofibroblast Properties and Present in Multiple Sclerosis Lesions.

    PubMed

    Vedrenne, Nicolas; Sarrazy, Vincent; Richard, Laurence; Bordeau, Nelly; Battu, Serge; Billet, Fabrice; Desmoulière, Alexis

    2017-08-01

    A wide heterogeneity of lesions can affect the central nervous system (CNS). In all situations where neurons are damaged, including multiple sclerosis (MS), a common reactive astrocytosis is present. Sedimentation field-flow fractionation (SdFFF) was used to sort astrocyte subpopulations. After SdFFF elution, cells, prepared from rat newborn cortex, were cultured and analyzed by immunocytofluorescence for glial fibrillary acidic protein (GFAP) and α-smooth muscle (SM) actin (a specific marker for myofibroblasts) expression. Cell contractile capacity was studied. Samples from patients with MS were also analyzed. Three main fractions (F1, F2, and F3) were isolated and compared with the total eluted population (TP). TP, F1, F2, and F3, contained respectively 74, 96, 12, and 98% of GFAP expressing astrocytes. In F3, astrocytes only expressed GFAP while in F1, astrocytes expressed both GFAP and α-SM actin. In F2 and TP, α-SM actin expression was barely detected. F3-derived cells showed higher contractile capacities compared with F1-derived cells. In one specific case of MS known as Baló's concentric MS, astrocytes expressing both GFAP and α-SM actin were detected. Using SdFFF, a population of astrocytes presenting myofibroblast properties was isolated. This subpopulation of astrocytes was also observed in a MS sample suggesting that it could be involved in lesion formation and remodeling during CNS pathologies.

  13. The 150th anniversary of the first depiction of the lesions of multiple sclerosis.

    PubMed Central

    Compston, A

    1988-01-01

    The clinical and pathological features of multiple sclerosis were fully described, in France and subsequently in England, during the latter half of the XIXth century but clinical descriptions, personal accounts and depictions of the disease had appeared at various times over the previous 50 years. Jean Cruveilhier is usually credited with having first illustrated the lesions of multiple sclerosis in the second tome of his pathological atlas which bears the title date 1835. But the 40 livraisons which make up this work were published separately in parts and documentary evidence contained within the second volume indicates that the putative case of multiple sclerosis cannot have appeared earlier than 1841. Robert Carswell also may have published his pathological atlas in parts but the work was completed by 1838 and so his depiction of the lesions of multiple sclerosis, appearing on plate 4 fig 1, predates Cruveilhier's by at least three years. Curiously, Carswell and Cruveilhier each observed their pathological material in Paris but they cannot have depicted the same individual. 1988 is therefore the 150th anniversary of the depiction of the lesions of multiple sclerosis; the unnamed patient was French, the illustrator a Scotsman. PMID:3066846

  14. Quantitative susceptibility mapping (QSM) of white matter multiple sclerosis lesions: interpreting positive susceptibility and the presence of iron

    PubMed Central

    Wisnieff, Cynthia; Ramanan, Sriram; Olesik, John; Gauthier, Susan; Wang, Yi; Pitt, David

    2014-01-01

    Purpose Within multiple sclerosis (MS) lesions iron is present in chronically activated microglia. Thus, iron detection with MRI might provide a biomarker for chronic inflammation within lesions. Here, we examine contributions of iron and myelin to magnetic susceptibility of lesions on quantitative susceptibility mapping (QSM). Methods Fixed MS brain tissue was assessed with MRI including gradient echo data, which was processed to generate field (phase), R2* and QSM. Five lesions were sectioned and evaluated by immunohistochemistry for presence of myelin, iron and microglia/macrophages. Two of the lesions had an elemental analysis for iron concentration mapping, and their phospholipid content was estimated from the difference in the iron and QSM data. Results Three of the five lesions had substantial iron deposition that was associated with microglia and positive susceptibility values. For the two lesions with elemental analysis, the QSM derived phospholipid content maps were consistent with myelin labeled histology. Conclusion Positive susceptibility values with respect to water indicate the presence of iron in MS lesions, though both demyelination and iron deposition contribute to QSM. PMID:25137340

  15. Imaging the tip of the iceberg: visualization of cortical lesions in multiple sclerosis.

    PubMed

    Seewann, Alexandra; Vrenken, Hugo; Kooi, Evert-Jan; van der Valk, Paul; Knol, Dirk L; Polman, Chris H; Pouwels, Petra J W; Barkhof, Frederik; Geurts, Jeroen J G

    2011-10-01

    Cortical lesions (CLs) occur frequently in multiple sclerosis (MS), but only few CLs are observed on conventional magnetic resonance imaging (MRI). Why some CLs are visible and others are not is currently unknown. Here, we investigated whether CLs that are visible on conventional MRI differ from MRI-invisible CLs in terms of underlying histopathology and quantitative MRI (qMRI) measures. A total of 16 brain slices from 10 patients with chronic MS were analysed histopathologically and with conventional and qMRI. A region-of-interest approach was used to compare MRI-visible CLs with MRI-invisible CLs. Although under-powering cannot be completely excluded in this study, MRI-visible CLs did not seem to differ from MRI-invisible CLs in terms of histopathology or qMRI measures. They were, however, significantly larger than their invisible counterparts (mean 13.3 ± 1.7 mm(2) versus 6.9 ± 1.3 mm(2); p = 0.001). Furthermore, the number of MRI-visible lesions correlated with the overall number of CLs in the brain slice (r = 0.96, p < 0.01) and with the overall percentage of demyelination (r = 0.78, p < 0.01) per hemispheric brain slice. MRI visibility of CLs is determined by lesion size, and not by any distinctive underlying pathology. Visible CLs are associated with a higher total cortical lesion load, which suggests that when CLs in patients with MS become detectable on MRI, they merely represent 'the tip of the pathological iceberg'.

  16. 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.

  17. Detection of lesions in mammographic structure

    NASA Astrophysics Data System (ADS)

    Burgess, Arthur E.; Jacobson, Francine L.; Judy, Philip F.

    1999-05-01

    This paper is a report on very surprising results from recent work on detection of real lesions in digitized mammograms. The experiments were done using a novel experimental procedure with hybrid images. The lesions (signals) were real tumor masses extracted from breast tissue specimen radiographs. In the detection experiments, the tumors were added to digitized normal mammographic backgrounds. The results of this new work have been both novel and very surprising. Contrast thresholds increased with increasing lesion size for lesions larger than approximately 1 mm in diameter. Earlier work with white noise, radiographic image noise, computed tomography (CT) noise and some types of patient structure have accustomed us to a particular relationship between lesion size and contrast for constant detectability. All previous contrast/detail (CD) diagrams have been similar, the contrast threshold decreases as lesion size increases and flattens at large lesion sizes. The CD diagram for lesion detection in mammographic structure is completely different. It will be shown that this is a consequence of the power-law dependence of the projected breast tissue structure spectral density on spatial frequency. Mammographic tissue structure power spectra have the form P(f) equals B/f(beta ), with an average exponent of approximately 3 (range from 2 to 4), and are approximately isotropic (small angular dependence). Results for two-alternative forced-choice (2AFC) signal detection experiments using 4 tumor lesions and one mathematically generated signal will be presented. These results are for an unbiased selection of mammographic backgrounds. It is possible that an additional understanding of the effects of breast structure on lesion detectability can be obtained by investigating detectability in various classes of mammographic backgrounds. This will be the subject of future research.

  18. D313Y mutation in the differential diagnosis of white matter lesions: Experiences from a multiple sclerosis outpatient clinic.

    PubMed

    Becker, Jana; Rolfs, Arndt; Karabul, Nesrin; Berlit, Peter; Kraemer, Markus

    2016-10-01

    White matter lesions (WML) in younger patients might be due to a variety of neurological disorders. Fabry disease (FD), an x-linked inherited lysosomal storage disorder, happens to be misdiagnosed as multiple sclerosis (MS). In two middle-aged female patients, presenting bilateral WML, diagnosis of MS turned out to be doubtful. Human genetic analysis presented the Fabry mutation D313Y, in which clinical impact is still unclear. Disease manifestations outside the central nervous system were not detected. Our findings support the suspicion that Fabry mutation D313Y may be involved in neural damage resulting in WML. © The Author(s), 2016.

  19. A case of pediatric multiple sclerosis presenting with a tumefactive demyelinating lesion.

    PubMed

    Majima, Hisakazu; Ito, Tsuyoshi; Koyama, Norihisa

    2017-02-25

    Pediatric multiple sclerosis accompanied by a tumefactive demyelinating lesion (TDL) is extremely rare. Because it is very difficult to distinguish TDLs from neoplasms, invasive brain biopsies are required for a definitive diagnosis. MR spectroscopy (MRS) without brain biopsy was recently shown diagnostic in some patients with TDLs, based on the elevation of glutamate/glutamine peaks. This report describes the clinical course of a 9-year-old girl with multiple sclerosis following a TDL and discusses the usefulness of MRS and brain biopsies to diagnose TDLs.

  20. Progressive oil-spot-like lesion in multiple sclerosis.

    PubMed

    Petrescu, A

    1981-01-01

    The demyelinating lesion in MS being characterised by an evolutive polymorphism, led to different opinions about the identification of the hypercellularity. The present work deals with data concerning the abundance and the early appearance of macrophages (M) within the lesion, studied with lipid histochemistry methods. The disposition of 3 various types of previously described M, with different lipid content, demonstrates the progressive centrifugal evolution of the recent lesion. At the edge the M are filled exclusively with intensely Baker (phospholipids) stained myelinic granules whereas inside they have a mixed myelinic and sudano-osmiophylic (esterocholesterolic) composition as revealed by Sudan red, Oil rd, Otan and Schultz methods. Surrounding vessels, in the centre of the lesion, M contain exclusively sudano-osmiophylic (esterocholesterolic) granules and crystals. This arrangement of M as to AGE is due to the progressive disintegrative cycle of phagocyted myelin: the youngest at the edge and those undergoing myelin disintegration towards the centre. It is demonstrative for the progressive and centrifugally oil-spot-like extension of the lesion and might explain the round-shape of the small lesions which stop their extension without any morphological correlations.

  1. Detection of Protein Aggregates in Brain and Cerebrospinal Fluid Derived from Multiple Sclerosis Patients

    PubMed Central

    David, Monique Antoinette; Tayebi, Mourad

    2014-01-01

    Studies of the properties of soluble oligomer species of amyloidogenic proteins, derived from different proteins with little sequence homology, have indicated that they share a common structure and may share similar pathogenic mechanisms. Amyloid β, tau protein, as well as amyloid precursor protein normally associated with Alzheimer’s disease and Parkinson’s disease were found in lesions and plaques of multiple sclerosis patients. The objective of the study is to investigate whether brain and cerebrospinal fluid (CSF) samples derived from multiple sclerosis patients demonstrate the presence of soluble oligomers normally associated with protein-misfolding diseases such as Alzheimer’s disease. We have used anti-oligomer monoclonal antibodies to immunodetect soluble oligomers in CSF and brain tissues derived from multiple sclerosis patients. In this report, we describe the presence of soluble oligomers in the brain tissue and cerebral spinal fluid of multiple sclerosis patients detected with our monoclonal anti-oligomer antibodies with Western blot and Sandwich enzyme-linked immunosorbent assay (sELISA). These results might suggest that protein aggregation plays a role in multiple sclerosis pathogenesis although further and more refined studies are needed to confirm the role of soluble aggregates in multiple sclerosis. PMID:25520699

  2. Auditory evoked potentials and vestibular evoked myogenic potentials in evaluation of brainstem lesions in multiple sclerosis.

    PubMed

    Ivanković, Anita; Nesek Mađarić, Vesna; Starčević, Katarina; Krbot Skorić, Magdalena; Gabelić, Tereza; Adamec, Ivan; Habek, Mario

    2013-05-15

    The aim of this study was to determine the roles of magnetic resonance imaging (MRI), auditory evoked potentials (AEP) and vestibular evoked myogenic potentials (VEMP) in the evaluation of brainstem involvement in multiple sclerosis (MS). Altogether 32 patients with the diagnosis of MS participated in the study. The following data was collected from all patients: age, gender, Expanded Disability Status Scale (EDSS) score, brainstem functional system score (BSFS) (part of the EDSS evaluating brainstem symptomatology), and involvement of the brainstem on the brain MRI. AEP and ocular VEMP (oVEMP) and cervical VEMP (cVEMP) were studied in all patients. BSFS, MRI, AEP, oVEMP and cVEMP involvement of the brainstem was evident in 9 (28.1%), 14 (43.8%), 7 (21.9%), 12 (37.5%) and 10 (31.0%) patients, respectively. None of the tests used showed statistically significant advantage in the detection of brainstem lesions. When combining oVEMP and cVEMP 18 (56.3%) patients showed brainstem involvement. This combination showed brainstem involvement in greater percentage than BSFS or AEP, with statistical significance (p=0.035 and p=0.007, respectively). VEMP is a reliable method in detection of brainstem involvement in MS. It is comparable with MRI, but superior to clinical examination or AEP. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Cognitive impairment and the regional distribution of cerebellar lesions in multiple sclerosis.

    PubMed

    Tobyne, Sean M; Ochoa, Wilson B; Bireley, J Daniel; Smith, Victoria Mj; Geurts, Jeroen Jg; Schmahmann, Jeremy D; Klawiter, Eric C

    2017-09-01

    Cerebellar lesions are often reported in relapsing-remitting multiple sclerosis (RRMS) and have been associated with impaired motor function and cognitive status. However, prior research has primarily focused on summary measures of cerebellar involvement (e.g. total lesion load, gray/white matter volume) and not on the effect of lesion load within specific regions of cerebellar white matter. Spatially map the probability of cerebellar white matter lesion (CWML) occurrence in RRMS and explore the relationship between cognitive impairment and lesion (CWML) location within the cerebellum. High-resolution structural magnetic resonance imaging (MRI) was acquired on 16 cognitively impaired (CI) and 15 cognitively preserved (CP) RRMS subjects at 3T and used for lesion identification and voxel-based lesion-symptom mapping (VLSM). CI RRMS demonstrated a predilection for the middle cerebellar peduncle (MCP). VLSM results indicate that lesions of the MCP are significantly associated with CI in RRMS. Measures of cerebellar lesion load were correlated with age at disease onset but not disease duration. A specific pattern of cerebellar lesions involving the MCP, rather than the total CWML load, contributes to cognitive dysfunction in RRMS. Cerebellar lesion profiles may provide a biomarker of current or evolving risk for cognitive status change in RRMS.

  4. Review of automatic segmentation methods of multiple sclerosis white matter lesions on conventional magnetic resonance imaging.

    PubMed

    García-Lorenzo, Daniel; Francis, Simon; Narayanan, Sridar; Arnold, Douglas L; Collins, D Louis

    2013-01-01

    Magnetic resonance (MR) imaging is often used to characterize and quantify multiple sclerosis (MS) lesions in the brain and spinal cord. The number and volume of lesions have been used to evaluate MS disease burden, to track the progression of the disease and to evaluate the effect of new pharmaceuticals in clinical trials. Accurate identification of MS lesions in MR images is extremely difficult due to variability in lesion location, size and shape in addition to anatomical variability between subjects. Since manual segmentation requires expert knowledge, is time consuming and is subject to intra- and inter-expert variability, many methods have been proposed to automatically segment lesions. The objective of this study was to carry out a systematic review of the literature to evaluate the state of the art in automated multiple sclerosis lesion segmentation. From 1240 hits found initially with PubMed and Google scholar, our selection criteria identified 80 papers that described an automatic lesion segmentation procedure applied to MS. Only 47 of these included quantitative validation with at least one realistic image. In this paper, we describe the complexity of lesion segmentation, classify the automatic MS lesion segmentation methods found, and review the validation methods applied in each of the papers reviewed. Although many segmentation solutions have been proposed, including some with promising results using MRI data obtained on small groups of patients, no single method is widely employed due to performance issues related to the high variability of MS lesion appearance and differences in image acquisition. The challenge remains to provide segmentation techniques that work in all cases regardless of the type of MS, duration of the disease, or MRI protocol, and this within a comprehensive, standardized validation framework. MS lesion segmentation remains an open problem.

  5. Progressive Injury in Chronic Multiple Sclerosis Lesions Is Gender-Specific: A DTI Study

    PubMed Central

    Klistorner, Alexander; Wang, Chenyu; Yiannikas, Con; Graham, Stuart L.; Parratt, John; Barnett, Michael H.

    2016-01-01

    Objective To evaluate the longitudinal integrity of white matter tracts in patients with relapsing remitting multiple sclerosis (RRMS) as determined by changes in diffusivity indices of lesional and non-lesional white matter in the optic radiation over 12 months. Methods The optic radiation (OR) was identified in sixty RRMS patients using probabilistic tractography. MS lesions were segmented on FLAIR T2 images and a lesion mask was intersected with the co-registered OR. Lesions within the OR were identified in 39 patients. Voxel-based analysis of axial diffusivity (AD) and radial diffusivity (RD) within OR lesions and non-lesional normal appearing white matter (NAWM) was performed at baseline and 12 months in 34 patients (five patients excluded due to new OR lesions). Results Both RD and AD demonstrated much higher values within the lesions compared with non-lesional NAWM. There was a significant (p<0.001) increase of lesional AD and RD during the follow-up period. This increase, however, was driven almost entirely by the male cohort, in which a significantly greater change in both AD (M-2.7%, F-0.9%) and RD (M-4.6%, F-0.7%) was observed during the follow-up period. Non-lesional NAWM also demonstrated an increase in both AD and RD, albeit on a much lesser scale (1.0% and 0.6% respectively). In contradistinction to lesions, the diffusivity change in non-lesional NAWM was similar between sexes. Conclusions The evolution of AD and RD in chronic MS lesions over 12 months suggests ongoing inflammatory demyelinating activity accompanied by axonal loss. In addition, our findings are consistent with the recently observed trend of more rapid clinical progression in males and establish a potential in vivo biomarker of gender dichotomy by demonstrating a significantly faster rate of microstructural change in the chronic lesions of male patients with MS. PMID:26901540

  6. Progressive Injury in Chronic Multiple Sclerosis Lesions Is Gender-Specific: A DTI Study.

    PubMed

    Klistorner, Alexander; Wang, Chenyu; Yiannikas, Con; Graham, Stuart L; Parratt, John; Barnett, Michael H

    2016-01-01

    To evaluate the longitudinal integrity of white matter tracts in patients with relapsing remitting multiple sclerosis (RRMS) as determined by changes in diffusivity indices of lesional and non-lesional white matter in the optic radiation over 12 months. The optic radiation (OR) was identified in sixty RRMS patients using probabilistic tractography. MS lesions were segmented on FLAIR T2 images and a lesion mask was intersected with the co-registered OR. Lesions within the OR were identified in 39 patients. Voxel-based analysis of axial diffusivity (AD) and radial diffusivity (RD) within OR lesions and non-lesional normal appearing white matter (NAWM) was performed at baseline and 12 months in 34 patients (five patients excluded due to new OR lesions). Both RD and AD demonstrated much higher values within the lesions compared with non-lesional NAWM. There was a significant (p<0.001) increase of lesional AD and RD during the follow-up period. This increase, however, was driven almost entirely by the male cohort, in which a significantly greater change in both AD (M-2.7%, F-0.9%) and RD (M-4.6%, F-0.7%) was observed during the follow-up period. Non-lesional NAWM also demonstrated an increase in both AD and RD, albeit on a much lesser scale (1.0% and 0.6% respectively). In contradistinction to lesions, the diffusivity change in non-lesional NAWM was similar between sexes. The evolution of AD and RD in chronic MS lesions over 12 months suggests ongoing inflammatory demyelinating activity accompanied by axonal loss. In addition, our findings are consistent with the recently observed trend of more rapid clinical progression in males and establish a potential in vivo biomarker of gender dichotomy by demonstrating a significantly faster rate of microstructural change in the chronic lesions of male patients with MS.

  7. 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.

  8. 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.

  9. 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.

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

    PubMed

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

    2015-02-01

    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.

  11. 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.

  12. Multiple sclerosis lesions and irreversible brain tissue damage: a comparative ultrahigh-field strength magnetic resonance imaging study.

    PubMed

    Sinnecker, Tim; Mittelstaedt, Paul; Dörr, Jan; Pfueller, Caspar F; Harms, Lutz; Niendorf, Thoralf; Paul, Friedemann; Wuerfel, Jens

    2012-06-01

    In current clinical practice, T2-weighted magnetic resonance imaging (MRI) is commonly applied to quantify the accumulated multiple sclerosis (MS)lesion load, whereas T1-weighted sequences are used to differentiate edema, blood-brain barrier breakdown by contrast enhancement, and irreversible brain tissue damage(commonly called “black holes” owing to the loss of signal intensity in T1-weighted sequences). Black holes are histopathologically associated with axonal loss and severe tissue destruction. In addition, double inversion recovery techniques were developed to improve the sensitivity to cortical lesions. To demonstrate the potential of ultrahigh-field 3-dimensional T1-weighted imaging using magnetization-prepared rapid acquisition and multiple gradient echoes(MPRAGE) to detect and characterize white and gray matter pathology in MS. Comparative study. The patients with MS were recruited from the outpatient clinics of the Neuro Cure Clinical Research Center and underwent 7-T brain MRI at the Berlin Ultrahigh Field Facility, both of which are in Berlin, Germany. Twenty patients with relapsing-remitting MS and 14 healthy controls underwent 7-T brain MRI, using a 24-channel receive head coil, and a subgroup of 18 patients with relapsing-remitting MS also underwent 1.5-T brain MRI. The imaging protocol included 2-dimensional T2-weighted fast low-angle shot (FLASH) and turbo inversion recovery magnitude (TIRM) sequences. For 3-dimensional T1-weighted imaging, the MPRAGE sequence was used. Each sequence was initially examined independently in separate analyses by an investigator blinded to all other data. In a second study, all detected lesions were retrospectively analyzed in a side-by-side comparison of all sequences. By use of 7-T T2-weighted FLASH imaging, 604 cerebral lesions were detected in the patients with relapsing-remitting MS (mean, 30.2 lesions per patient[range, 2-107 lesions per patient]), but none were detected in healthy controls. Cortical

  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. 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.

  15. Characterizing iron deposition in multiple sclerosis lesions using susceptibility weighted imaging

    PubMed Central

    Haacke, E. Mark; Makki, Malek; Ge, Yulin; Maheshwari, Megha; Sehgal, Vivek; Hu, Jiani; Selvan, Madeswaran; Wu, Zhen; Latif, Zahid; Xuan, Yang; Khan, Omar; Garbern, James; Grossman, Robert I.

    2009-01-01

    Purpose To investigate whether the variable forms of putative iron deposition seen with susceptibility weighted imaging (SWI) will lead to a set of multiple sclerosis (MS) lesion characteristics different than that seen in conventional MR imaging. Materials and Methods Twenty-seven clinically definite MS patients underwent brain scans using magnetic resonance imaging including: pre- and post-contrast T1-weighted, T2-weighted, FLAIR, and SWI at 1.5T, 3T and 4T. MS lesions were identified separately in each imaging sequence. Lesions identified in SWI were re-evaluated for their iron content using the SWI filtered phase images. Results There were a variety of new lesion characteristics identified by SWI and these were classified into six types. A total of 75 lesions were seen only with conventional imaging, 143 only with SWI and 204 by both. From the iron quantification measurements, a moderate linear correlation between signal intensity and iron content (phase) was established. Conclusion The amount of iron deposition in the brain may serve as a surrogate biomarker for different MS lesion characteristics. SWI showed many lesions missed by conventional methods and six different lesion characteristics. SWI was particularly effective at recognizing the presence of iron in MS lesions and in the basal ganglia and pulvinar thalamus. PMID:19243035

  16. 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

  17. 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.

  18. Search field size and lesion detection performance

    NASA Astrophysics Data System (ADS)

    Tipnis, Sameer; Huda, Walter; Hardie, Andrew; Ogden, Kent

    2010-04-01

    In this study, we evaluated the ability of an observer to identify abnormal foci on CT and how that ability is affected by changing the search field size from a whole abdomen to the liver region alone. A 2-Alternate Forced Choice (2 AFC) experimental paradigm was used to quantify observer detection performance. Each AFC experiment yielded the intensity needed to achieve 92% accuracy in lesion detection (I92%). Abdominal images were obtained at an x-ray tube voltage of 120 kV with a CTDIvol of 20 mGy. Circular lesions were generated by projecting spheres onto the image plane, followed by blurring function. Five lesion sizes (5 mm, 7 mm, 10 mm, 12 mm, and 15 mm), and four readers who were extensively trained in AFC methodology, were used in the 2AFC experiments. Each experiment was repeated 4 times to improve the experimental precision, as well as to provide an estimate of experimental uncertainty. For each observer, the experimental order of the 40 experiments was randomized to eliminate learning curve and/or observer fatigue. We measured contrast detail slopes for both Abdomen and Liver search field size, and determined ratio of I92% value for Abdomen search field to the corresponding I92% for the Liver search field (i.e., Rabd:liv). Values of Rabd:liv provides quantitative indicator of the relative difficulty of detection lesions in the whole Abdomen relative to lesion detection restricted to the Liver. The slope of the contrast detail curve for the Abdomen search field was -0.03, whereas the corresponding slope for the Liver search field was -0.18. Rabd:liv ranged between 1.3 and 1.6, with an average of 1.4 +/- 0.1. The value of Rabd:liv monotonically increased from 1.35 for 5 mm lesions to nearly 1.6 for the largest 15 mm lesion. The results of our study indicate that limiting the area of search to the liver on a CT of the abdomen improves the detection of mass lesions. This finding is almost certainly related to the fact that the liver provides a relatively

  19. Spinal cord lesions in children and adolescents with multiple sclerosis - Magnetic resonance imaging.

    PubMed

    Dębska, Joanna; Kotulska-Józwiak, Katarzyna; Pawliszak, Piotr; Bilska, Małgorzata; Chmielewski, Dariusz; Puzio, Iwona; Jurkiewicz, Elżbieta

    The purpose of our study was to determine the prevalence of spinal cord lesions revealed by magnetic resonance (MR) imaging in children and adolescents with clinically definite multiple sclerosis (MS). We retrospectively evaluated the spinal cord magnetic resonance examinations in a group of MS patients consisting of 58 children (37 girls and 21 boys) aged from 7 to 17.8 years (mean 13.7 years). All children met the criteria of clinically definite MS and had typical MS lesions revealed in the brain imaging. Spinal cord lesions, regardless of localization, were identified in 36 (62%) patients. In 22 of 58 patients (38%) no lesions were observed. The plaques were found in the cervical spinal cord and the thoracic spinal cord in 30 out of 36 (86.1%) and in 31 out of 36 (88.6%) patients, respectively. Contrast enhancement was noticed in 10 out of 36 patients (27.7%) and was not correlated with the number of lesions present. We noticed a tendency to higher EDSS score in patients with lesions in more than 1 spinal cord region. Our study showed that spinal cord lesions are more frequently present in patients with complex neurological disability. The prevalence of spinal cord lesions in children and adolescents with MS is high. Therefore, spinal cord MRI should be included in diagnostic program of MS. Copyright © 2016. Published by Elsevier Urban & Partner Sp. z o.o.

  20. Decoding diffusivity in multiple sclerosis: analysis of optic radiation lesional and non-lesional white matter.

    PubMed

    Klistorner, Alexander; Vootakuru, Nikitha; Wang, Chenyu; Yiannikas, Con; Graham, Stuart L; Parratt, John; Garrick, Raymond; Levin, Netta; Masters, Lynette; Lagopoulos, Jim; Barnett, Michael H

    2015-01-01

    Diffusion tensor imaging (DTI) has been suggested as a new promising tool in MS that may provide greater pathological specificity than conventional MRI, helping, therefore, to elucidate disease pathogenesis and monitor therapeutic efficacy. However, the pathological substrates that underpin alterations in brain tissue diffusivity are not yet fully delineated. Tract-specific DTI analysis has previously been proposed in an attempt to alleviate this problem. Here, we extended this approach by segmenting a single tract into areas bound by seemingly similar pathological processes, which may better delineate the potential association between DTI metrics and underlying tissue damage. Several compartments were segmented in optic radiation (OR) of 50 relapsing-remitting MS patients including T2 lesions, proximal and distal parts of fibers transected by lesion and fibers with no discernable pathology throughout the entire length of the OR. Asymmetry analysis between lesional and non-lesional fibers demonstrated a marked increase in Radial Diffusivity (RD), which was topographically limited to focal T2 lesions and potentially relates to the lesional myelin loss. A relative elevation of Axial Diffusivity (AD) in the distal part of the lesional fibers was observed in a distribution consistent with Wallerian degeneration, while diffusivity in the proximal portion of transected axons remained normal. A moderate, but significant elevation of RD in OR non-lesional fibers was strongly associated with the global (but not local) T2 lesion burden and is probably related to microscopic demyelination undetected by conventional MRI. This study highlights the utility of the compartmentalization approach in elucidating the pathological substrates of diffusivity and demonstrates the presence of tissue-specific patterns of altered diffusivity in MS, providing further evidence that DTI is a sensitive marker of tissue damage in both lesions and NAWM. Our results suggest that, at least within

  1. Decoding Diffusivity in Multiple Sclerosis: Analysis of Optic Radiation Lesional and Non-Lesional White Matter

    PubMed Central

    Klistorner, Alexander; Vootakuru, Nikitha; Wang, Chenyu; Yiannikas, Con; Graham, Stuart L.; Parratt, John; Garrick, Raymond; Levin, Netta; Masters, Lynette; Lagopoulos, Jim; Barnett, Michael H.

    2015-01-01

    Objectives Diffusion tensor imaging (DTI) has been suggested as a new promising tool in MS that may provide greater pathological specificity than conventional MRI, helping, therefore, to elucidate disease pathogenesis and monitor therapeutic efficacy. However, the pathological substrates that underpin alterations in brain tissue diffusivity are not yet fully delineated. Tract-specific DTI analysis has previously been proposed in an attempt to alleviate this problem. Here, we extended this approach by segmenting a single tract into areas bound by seemingly similar pathological processes, which may better delineate the potential association between DTI metrics and underlying tissue damage. Method Several compartments were segmented in optic radiation (OR) of 50 relapsing-remitting MS patients including T2 lesions, proximal and distal parts of fibers transected by lesion and fibers with no discernable pathology throughout the entire length of the OR. Results Asymmetry analysis between lesional and non-lesional fibers demonstrated a marked increase in Radial Diffusivity (RD), which was topographically limited to focal T2 lesions and potentially relates to the lesional myelin loss. A relative elevation of Axial Diffusivity (AD) in the distal part of the lesional fibers was observed in a distribution consistent with Wallerian degeneration, while diffusivity in the proximal portion of transected axons remained normal. A moderate, but significant elevation of RD in OR non-lesional fibers was strongly associated with the global (but not local) T2 lesion burden and is probably related to microscopic demyelination undetected by conventional MRI. Conclusion This study highlights the utility of the compartmentalization approach in elucidating the pathological substrates of diffusivity and demonstrates the presence of tissue-specific patterns of altered diffusivity in MS, providing further evidence that DTI is a sensitive marker of tissue damage in both lesions and NAWM. Our

  2. The effect of hypointense white matter lesions on automated gray matter segmentation in multiple sclerosis.

    PubMed

    Gelineau-Morel, Rose; Tomassini, Valentina; Jenkinson, Mark; Johansen-Berg, Heidi; Matthews, Paul M; Palace, Jacqueline

    2012-12-01

    Previous imaging studies assessing the relationship between white matter (WM) damage and matter (GM) atrophy have raised the concern that Multiple Sclerosis (MS) WM lesions may affect measures of GM volume by inducing voxel misclassification during intensity-based tissue segmentation. Here, we quantified this misclassification error in simulated and real MS brains using a lesion-filling method. Using this method, we also corrected GM measures in patients before comparing them with controls in order to assess the impact of this lesion-induced misclassification error in clinical studies. We found that higher WM lesion volumes artificially reduced total GM volumes. In patients, this effect was about 72% of that predicted by simulation. Misclassified voxels were located at the GM/WM border and could be distant from lesions. Volume of individual deep gray matter (DGM) structures generally decreased with higher lesion volumes, consistent with results from total GM. While preserving differences in GM volumes between patients and controls, lesion-filling correction revealed more lateralised DGM shape changes in patients, which were not evident with the original images. Our results confirm that WM lesions can influence MRI measures of GM volume and shape in MS patients through their effect on intensity-based GM segmentation. The greater effect of lesions at increasing levels of damage supports the use of lesion-filling to correct for this problem and improve the interpretability of the results. Volumetric or morphometric imaging studies, where lesion amount and characteristics may vary between groups of patients or change over time, may especially benefit from this correction.

  3. Brain lesion volume and neuropsychological function predict efficacy of treatment for depression in multiple sclerosis.

    PubMed

    Mohr, David C; Epstein, Lucy; Luks, Tracy L; Goodkin, Donald; Cox, Darcy; Goldberg, Alison; Chin, Cynthia; Nelson, Sarah

    2003-12-01

    This study examined the effects of brain lesions and neuropsychological impairment on the efficacy of treatment for depression in patients with comorbid diagnoses of multiple sclerosis (MS) and major depressive disorder (MDD). Thirty patients meeting criteria for MS and MDD received 1 of 3 16-week treatments for depression and were followed for 6 months following treatment cessation. T2-weighted magnetic resonance imaging and neuropsychological evaluations were also obtained. End-of-treatment Beck Depression Inventory (BDI; A. T. Beck, C. H. Ward, M. Mendelson, J. Mock, & J. Erbaugh, 1961) results residualized for baseline BDI were related to right temporal periventricular lesion volume (R2=.32, p=.002) and left temporal grey-white junction lesion volume (R2=.19, p=.02) but were not statistically related to lesion volume in any other brain region or to neuropsychological function. BDI results at 6-month follow-up, residualized for end-of-treatment BDI, were predicted by total lesion volume (R2=.22, p=.005), lesion volume in many discrete areas, and neuropsychological functioning (R2=.29, p=.0009). The effect of total lesion volume on 6-month follow-up BDI results was fully mediated by neuropsychological function. (c) 2003 APA

  4. ACUTE MULTIPLE SCLEROSIS LESION: CONVERSION OF RESTRICTED DIFFUSION DUE TO VASOGENIC EDEMA

    PubMed Central

    Balashov, Konstantin E.; Latt Aung, Latt; Dhib-Jalbut, Suhayl; Keller, Irwin A.

    2009-01-01

    It is widely accepted that acute demyelinating plaques in patients with multiple sclerosis (MS) demonstrate increased apparent diffusion coefficient (ADC) and increased diffusion weighted imaging (DWI) signals on MRI. These imaging characteristics in acute MS lesions have been postulated to be due to peripheral vasogenic edema that typically increases the apparent diffusion coefficient (ADC). This assumption is commonly used to differentiate stroke from MS lesions since acute and subacute stroke lesions demonstrate increased DWI signal with reduced ADC due to acute cytotoxic edema. We report a case of active relapsing-remitting MS with two new symptomatic contrast-enhancing lesions. The lesions had reduced diffusion on the ADC map in the early acute phase of MS exacerbation. The reduced ADC signal was subsequently “converted” to increased ADC signal which coincided with the development of profound peripheral vasogenic edema seen on T2-weighted images. To our knowledge, this is the first serial MRI study describing decreased ADC signal in the early acute phase of contrast-enhancing MS lesion. The implications of decreased diffusion in the acute phase of MS lesions for the disease pathogenesis are discussed. PMID:19888931

  5. Within-lesion differences in quantitative MRI parameters predict contrast enhancement in multiple sclerosis.

    PubMed

    Jurcoane, Alina; Wagner, Marlies; Schmidt, Christoph; Mayer, Christoph; Gracien, Rene-Maxime; Hirschmann, Marc; Deichmann, Ralf; Volz, Steffen; Ziemann, Ulf; Hattingen, Elke

    2013-12-01

    To investigate the relationship between quantitative magnetic resonance imaging (qMRI) and contrast enhancement in multiple sclerosis (MS) lesions. We compared maps of T1 relaxation time, proton density (PD), and magnetization transfer ratio (MTR) between lesions with and without contrast enhancement as quantified by the amount of T1 shortening postcontrast agent (CA). In 17 patients with relapsing-remitting MS (RRMS), 15 with progressive MS (PMS), and 17 healthy controls, T1, PD, and MTR were measured at 3T and T1-mapping was repeated after CA administration. Manually drawn MS-lesions (3D-FLAIR) were labeled as enhancing if post-CA T1-shortening exceeded mean T1-shortening in normal-appearing white matter (NAWM) by at least 2 standard deviations. Precontrast T1, PD, and MTR were compared in enhancing lesions, nonenhancing lesions, NAWM, and gray matter. Precontrast T1, PD, and MTR differed significantly between enhancing and nonenhancing lesions in RRMS and PMS patients (all P < 0.01). In PMS patients, PD of NAWM, enhancing, and nonenhancing lesions and MTR and T1 of gray matter differed significantly from RRMS and controls. Only MTR of gray matter differed between RRMS and controls. Contrast enhancement in MS quantified by relative T1 shortening may be predicted by precontrast abnormalities of T1, PD, and MTR and likely represents blood-brain barrier damage. Copyright © 2013 Wiley Periodicals, Inc.

  6. 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.

  7. Vibration sonoelastography and the detectability of lesions.

    PubMed

    Parker, K J; Fu, D; Graceswki, S M; Yeung, F; Levinson, S F

    1998-11-01

    Vibration sonoelastography has been developed for the detection of hard lesions in relatively soft tissue. The basic concept is to propagate low-amplitude and low-frequency shear waves (with displacements below 0.1 mm and frequencies typically below 1000 Hz) through deep organs, and displaying the vibration response in real-time using advanced color Doppler imaging techniques. A hard inhomogeneity, such as a tumor, will produce a localized disturbance in the vibration pattern, forming the basis for detection even when the tumor is isoechoic on B-scan images. This paper focuses on the important quantitative issues concerning the detectability or inherent contrast of lesions. The specific factors of lesion size, relative stiffness and vibration frequency are studied using theoretical models, finite element methods and experimental measurements on tissue-mimicking materials. The results indicate that detectability increases with vibration (shear wave) frequency; however, loss mechanisms ultimately limit the penetration of higher vibration frequencies (in the kHz range).

  8. NADPH oxidase expression in active multiple sclerosis lesions in relation to oxidative tissue damage and mitochondrial injury.

    PubMed

    Fischer, Marie T; Sharma, Rakhi; Lim, Jamie L; Haider, Lukas; Frischer, Josa M; Drexhage, Joost; Mahad, Don; Bradl, Monika; van Horssen, Jack; Lassmann, Hans

    2012-03-01

    Multiple sclerosis is a chronic inflammatory disease of the central nervous system, associated with demyelination and neurodegeneration. The mechanisms of tissue injury are poorly understood, but recent data suggest that mitochondrial injury may play an important role in this process. Mitochondrial injury can be triggered by reactive oxygen and nitric oxide species, and we recently provided evidence for oxidative damage of oligodendrocytes and dystrophic axons in early stages of active multiple sclerosis lesions. In this study, we identified potential sources of reactive oxygen and nitrogen species through gene expression in carefully staged and dissected lesion areas and by immunohistochemical analysis of protein expression. Genome-wide microarrays confirmed mitochondrial injury in active multiple sclerosis lesions, which may serve as an important source of reactive oxygen species. In addition, we found differences in the gene expression levels of various nicotinamide adenine dinucleotide phosphate oxidase subunits between initial multiple sclerosis lesions and control white matter. These results were confirmed at the protein level by means of immunohistochemistry, showing upregulation of the subunits gp91phox, p22phox, p47phox, nicotinamide adenine dinucleotide phosphate oxidase 1 and nicotinamide adenine dinucleotide phosphate oxidase organizer 1 in activated microglia in classical active as well as slowly expanding lesions. The subunits gp91phox and p22phox were constitutively expressed in microglia and were upregulated in the initial lesion. In contrast, p47phox, nicotinamide adenine dinucleotide phosphate oxidase 1 and nicotinamide adenine dinucleotide phosphate oxidase organizer 1 expression were more restricted to the zone of initial damage or to lesions from patients with acute or early relapsing/remitting multiple sclerosis. Double labelling showed co-expression of the nicotinamide adenine dinucleotide phosphate oxidase subunits in activated microglia and

  9. NADPH oxidase expression in active multiple sclerosis lesions in relation to oxidative tissue damage and mitochondrial injury

    PubMed Central

    Fischer, Marie T.; Sharma, Rakhi; Lim, Jamie L.; Haider, Lukas; Frischer, Josa M.; Drexhage, Joost; Mahad, Don; Bradl, Monika; van Horssen, Jack

    2012-01-01

    Multiple sclerosis is a chronic inflammatory disease of the central nervous system, associated with demyelination and neurodegeneration. The mechanisms of tissue injury are poorly understood, but recent data suggest that mitochondrial injury may play an important role in this process. Mitochondrial injury can be triggered by reactive oxygen and nitric oxide species, and we recently provided evidence for oxidative damage of oligodendrocytes and dystrophic axons in early stages of active multiple sclerosis lesions. In this study, we identified potential sources of reactive oxygen and nitrogen species through gene expression in carefully staged and dissected lesion areas and by immunohistochemical analysis of protein expression. Genome-wide microarrays confirmed mitochondrial injury in active multiple sclerosis lesions, which may serve as an important source of reactive oxygen species. In addition, we found differences in the gene expression levels of various nicotinamide adenine dinucleotide phosphate oxidase subunits between initial multiple sclerosis lesions and control white matter. These results were confirmed at the protein level by means of immunohistochemistry, showing upregulation of the subunits gp91phox, p22phox, p47phox, nicotinamide adenine dinucleotide phosphate oxidase 1 and nicotinamide adenine dinucleotide phosphate oxidase organizer 1 in activated microglia in classical active as well as slowly expanding lesions. The subunits gp91phox and p22phox were constitutively expressed in microglia and were upregulated in the initial lesion. In contrast, p47phox, nicotinamide adenine dinucleotide phosphate oxidase 1 and nicotinamide adenine dinucleotide phosphate oxidase organizer 1 expression were more restricted to the zone of initial damage or to lesions from patients with acute or early relapsing/remitting multiple sclerosis. Double labelling showed co-expression of the nicotinamide adenine dinucleotide phosphate oxidase subunits in activated microglia and

  10. Lesion border detection in dermoscopy images.

    PubMed

    Celebi, M Emre; Iyatomi, Hitoshi; Schaefer, Gerald; Stoecker, William V

    2009-03-01

    Dermoscopy is one of the major imaging modalities used in the diagnosis of melanoma and other pigmented skin lesions. Due to the difficulty and subjectivity of human interpretation, computerized analysis of dermoscopy images has become an important research area. One of the most important steps in dermoscopy image analysis is the automated detection of lesion borders. In this article, we present a systematic overview of the recent border detection methods in the literature paying particular attention to computational issues and evaluation aspects. Common problems with the existing approaches include the acquisition, size, and diagnostic distribution of the test image set, the evaluation of the results, and the inadequate description of the employed methods. Border determination by dermatologists appears to depend upon higher-level knowledge, therefore it is likely that the incorporation of domain knowledge in automated methods will enable them to perform better, especially in sets of images with a variety of diagnoses.

  11. Lesion Border Detection in Dermoscopy Images

    PubMed Central

    Celebi, M. Emre; Schaefer, Gerald; Iyatomi, Hitoshi; Stoecker, William V.

    2009-01-01

    Background Dermoscopy is one of the major imaging modalities used in the diagnosis of melanoma and other pigmented skin lesions. Due to the difficulty and subjectivity of human interpretation, computerized analysis of dermoscopy images has become an important research area. One of the most important steps in dermoscopy image analysis is the automated detection of lesion borders. Methods In this article, we present a systematic overview of the recent border detection methods in the literature paying particular attention to computational issues and evaluation aspects. Conclusion Common problems with the existing approaches include the acquisition, size, and diagnostic distribution of the test image set, the evaluation of the results, and the inadequate description of the employed methods. Border determination by dermatologists appears to depend upon higher-level knowledge, therefore it is likely that the incorporation of domain knowledge in automated methods will enable them to perform better, especially in sets of images with a variety of diagnoses. PMID:19121917

  12. Detection of Helicobacter pylori in Oral Lesions

    PubMed Central

    Irani, Soussan; Monsef Esfahani, Alireza; Bidari Zerehpoush, Farahnaz

    2013-01-01

    Background and aims. Helicobacter pylori is a microaerophilic gram-negative spiral organism. It is recognized as the etiologic factor for peptic ulcers, gastric adenocarcinoma and gastric lymphoma. Recently, it has been isolated from dental plaque and the dorsum of the tongue. This study was designed to assess the association between H. pylori and oral lesions such as ulcerative/inflammatory lesions, squamous cell carcinoma (SCC) and primary lymphoma. Materials and methods. A total of 228 biopsies diagnosed as oral ulcerative/inflammatory lesions, oral squamous cell carcinoma (OSCC) and oral primary lymphoma were selected from the archives of the Pathology Department. Thirty-two samples that were diagnosed as being without any pathological changes were selected as the control group. All the paraffin blocks were cut for hematoxylin and eosin staining to confirm the diagnoses and then the samples were prepared for immunohistochemistry staining. Data were collected and analyzed. Results. Chi-squared test showed significant differences between the frequency of H. pylori positivity in normal tissue and the lesions were examined (P=0.000). In addition, there was a statistically significant difference between the lesions examined (P=0.042). Chi-squared test showed significant differences between H. pylori positivity and different tissue types except inside the muscle layer as follows: in epithelium and in lamina propria (P=0.000), inside the blood vessels (P=0.003), inside the salivary gland duct (P=0.036), and muscle layer (P=0.122). Conclusion. There might be a relation between the presence of H. pylori and oral lesions. Therefore, early detection and eradication of H. pylori in high-risk patients are suggested. PMID:24578822

  13. MRI FLAIR lesion segmentation in multiple sclerosis: Does automated segmentation hold up with manual annotation?

    PubMed

    Egger, Christine; Opfer, Roland; Wang, Chenyu; Kepp, Timo; Sormani, Maria Pia; Spies, Lothar; Barnett, Michael; Schippling, Sven

    2017-01-01

    Magnetic resonance imaging (MRI) has become key in the diagnosis and disease monitoring of patients with multiple sclerosis (MS). Both, T2 lesion load and Gadolinium (Gd) enhancing T1 lesions represent important endpoints in MS clinical trials by serving as a surrogate of clinical disease activity. T2- and fluid-attenuated inversion recovery (FLAIR) lesion quantification - largely due to methodological constraints - is still being performed manually or in a semi-automated fashion, although strong efforts have been made to allow automated quantitative lesion segmentation. In 2012, Schmidt and co-workers published an algorithm to be applied on FLAIR sequences. The aim of this study was to apply the Schmidt algorithm on an independent data set and compare automated segmentation to inter-rater variability of three independent, experienced raters. MRI data of 50 patients with RRMS were randomly selected from a larger pool of MS patients attending the MS Clinic at the Brain and Mind Centre, University of Sydney, Australia. MRIs were acquired on a 3.0T GE scanner (Discovery MR750, GE Medical Systems, Milwaukee, WI) using an 8 channel head coil. We determined T2-lesion load (total lesion volume and total lesion number) using three versions of an automated segmentation algorithm (Lesion growth algorithm (LGA) based on SPM8 or SPM12 and lesion prediction algorithm (LPA) based on SPM12) as first described by Schmidt et al. (2012). Additionally, manual segmentation was performed by three independent raters. We calculated inter-rater correlation coefficients (ICC) and dice coefficients (DC) for all possible pairwise comparisons. We found a strong correlation between manual and automated lesion segmentation based on LGA SPM8, regarding lesion volume (ICC = 0.958 and DC = 0.60) that was not statistically different from the inter-rater correlation (ICC = 0.97 and DC = 0.66). Correlation between the two other algorithms (LGA SPM12 and LPA SPM12) and manual raters was weaker

  14. Detecting and Treating Occlusal Caries Lesions

    PubMed Central

    Stolpe, M.; Meyer-Lueckel, H.; Paris, S.

    2015-01-01

    The health gains and costs resulting from using different caries detection strategies might not only depend on the accuracy of the used method but also the treatment emanating from its use in different populations. We compared combinations of visual-tactile, radiographic, or laser-fluorescence–based detection methods with 1 of 3 treatments (non-, micro-, and invasive treatment) initiated at different cutoffs (treating all or only dentinal lesions) in populations with low or high caries prevalence. A Markov model was constructed to follow an occlusal surface in a permanent molar in an initially 12-y-old male German patient over his lifetime. Prevalence data and transition probabilities were extracted from the literature, while validity parameters of different methods were synthesized or obtained from systematic reviews. Microsimulations were performed to analyze the model, assuming a German health care setting and a mixed public-private payer perspective. Radiographic and fluorescence-based methods led to more overtreatments, especially in populations with low prevalence. For the latter, combining visual-tactile or radiographic detection with microinvasive treatment retained teeth longest (mean 66 y) at lowest costs (329 and 332 Euro, respectively), while combining radiographic or fluorescence-based detections with invasive treatment was the least cost-effective (<60 y, >700 Euro). In populations with high prevalence, combining radiographic detection with microinvasive treatment was most cost-effective (63 y, 528 Euro), while sensitive detection methods combined with invasive treatments were again the least cost-effective (<59 y, >690 Euro). The suitability of detection methods differed significantly between populations, and the cost-effectiveness was greatly influenced by the treatment initiated after lesion detection. The accuracy of a detection method relative to a “gold standard” did not automatically convey into better health or reduced costs. Detection

  15. Neuroaxonal regeneration is more pronounced in early multiple sclerosis than in traumatic brain injury lesions.

    PubMed

    Schirmer, Lucas; Merkler, Doron; König, Fatima B; Brück, Wolfgang; Stadelmann, Christine

    2013-01-01

    The extent of irreversible neuroaxonal damage is the key determinant of permanent disability in traumatic and inflammatory conditions of the central nervous system (CNS). Structural damage is nevertheless in part compensated by neuroplastic events. However, it is unknown whether the same kinetics and mechanisms of neuroaxonal de- and regeneration take place in inflammatory and traumatic conditions. We analyzed neuroaxonal degeneration and plasticity in early multiple sclerosis (MS) lesions and traumatic brain injury (TBI). Neuroaxonal degeneration identified by the presence of SMI31+ chromatolytic neurons and SMI32+ axonal profiles were characteristic features of leukocortical TBI lesions. Axonal transport disturbances as determined by amyloid precursor protein (APP)+ spheroids were present in both TBI and MS lesions to a similar degree. Neurons expressing growth-associated protein 43 (GAP43) and synaptophysin (Syn) were found under both pathological conditions. However, axonal swellings immunopositive for GAP43 and Syn clearly prevailed in subcortical MS lesions, suggesting a higher regenerative potential in MS. In this context, GAP43+/APP+ axonal spheroid ratios correlated with macrophage infiltration in TBI and MS lesions, supporting the idea that phagocyte activation might promote neuroplastic events. Furthermore, axonal GAP43+ and Syn+ swellings correlated with prolonged survival after TBI, indicating a sustained regenerative response.

  16. Abnormal endothelial tight junctions in active lesions and normal-appearing white matter in multiple sclerosis.

    PubMed

    Plumb, Jonnie; McQuaid, Stephen; Mirakhur, Meenakshi; Kirk, John

    2002-04-01

    Blood-brain barrier (BBB) breakdown, demonstrable in vivo by enhanced MRI is characteristic of new and expanding inflammatory lesions in relapsing-remitting and chronic progressive multiple sclerosis (MS). Subtle leakage may also occur in primary progressive MS. However, the anatomical route(s) of BBB leakage have not been demonstrated. We investigated the possible involvement of interendothelial tight junctions (TJ) by examining the expression of TJ proteins (occludin and ZO-1 ) in blood vessels in active MS lesions from 8 cases of MS and in normal-appearing white (NAWM) matter from 6 cases. Blood vessels (10-50 per frozen section) were scanned using confocal laser scanning microscopy to acquire datasets for analysis. TJ abnormalities manifested as beading, interruption, absence or diffuse cytoplasmic localization of fluorescence, or separation of junctions (putative opening) were frequent (affecting 40% of vessels) in oil-red-O-positive active plaques but less frequent in NAWM (15%), and in normal (< 2%) and neurological controls (6%). Putatively "open" junctions were seen in vessels in active lesions and in microscopically inflamed vessels in NAWM. Dual fluorescence revealed abnormal TJs in vessels with pre-mortem serum protein leakage. Abnormal or open TJs, associated with inflammation may contribute to BBB leakage in enhancing MRI lesions and may also be involved in subtle leakage in non-enhancing focal and diffuse lesions in NAWM. BBB disruption due to tight junctional pathology should be regarded as a significant form of tissue injury in MS, alongside demyelination and axonopathy.

  17. Objective and reproducible segmentation and quantification of tuberous sclerosis lesions in FLAIR brain MR images

    NASA Astrophysics Data System (ADS)

    Alderliesten, Tanja; Niessen, Wiro J.; Vincken, Koen L.; Maintz, J. B. Antoine; Jansen, Floor; van Nieuwenhuizen, Onno; Viergever, Max A.

    2001-07-01

    A semi-automatic segmentation method for Tuberous Sclerosis (TS) lesions in the brain has been developed. Both T1 images and Fluid Attenuated Inversion Recovery (FLAIR) images are integrated in the segmentation procedure. The segmentation procedure is mainly based on the notion of fuzzy connectedness. This approach uses the two basic concepts of adjacency and affinity to form a fuzzy relation between voxels in the image. The affinity is defined using two quantities that are both based on characteristics of the intensities in the lesion and surrounding brain tissue (grey and white matter). The semi-automatic method has been compared to results of manual segmentation. Manual segmentation is prone to interobserver and intraobserver variability. This was especially true for this particular study, where large variations were observed, which implies that a golden standard for comparison was not available. The method did perform within the variability of the observers and therefore has the potential to improve reproducibility of quantitative measurements.

  18. 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

  19. Three-Dimensional Shape and Surface Features Distinguish Multiple Sclerosis Lesions from Nonspecific White Matter Disease.

    PubMed

    Newton, Braeden D; Wright, Katy; Winkler, Mandy D; Bovis, Francesca; Takahashi, Masaya; Dimitrov, Ivan E; Sormani, Maria Pia; Pinho, Marco C; Okuda, Darin T

    2017-05-10

    There remains a need to further refine the ability of clinicians to differentiate multiple sclerosis (MS) from other disease etiologies. Here, we illustrate the value of 3-dimensional (3D) geometric shape and surface lesion characteristics between disease states. Standardized 3-Tesla 3D brain magnetic resonance imaging studies were performed on enrolled MS and nonspecific white matter (NSWM) patients. Focal supratentorial lesions were identified, reconstructed using maximum intensity projection, manually segmented, and 3D printed. Printed 3D models were randomly evaluated by three blinded raters for selected shape and surface characteristics. Regression models adjusting for age, disease duration, and individual patient effects were applied to assess lesion characteristics between patient groups. Patient-level and latent class analyses between groups were performed. A total of 1,001 supratentorial lesions were analyzed (710 MS; 291 NSWM) from 30 patients (19 with confirmed MS [11 female; median age = 33.6 years, range: 26.9-54.5], median disease duration = 2.2 years [.4-19.4]), 11 with verified nonspecific white matter (NSWM) disease without MS (11 female; median age = 55.0 years, range: 27.9-66.2). Lesions originating from MS in comparison to NSWM patients demonstrated a higher percentage of asymmetry (75.9% vs. 43%; OR: 4.39 [2.37-8.12]; P < .001), complex surface morphologies (65.9% vs. 27.8%; OR: 2.3 [1.74-3.05]; P < .001), and were multilobular (11.0% vs. .3%, P < .001), and elongated (12.8% vs. 2.4%, P < .001) in shape. Spatially, these traits were of higher frequency within the juxtacortical, deep white matter, and periventricular regions. Three-dimensional lesion data may provide new biologic insights related to injury along with offering another approach for determining the origin of lesion types. Copyright © 2017 by the American Society of Neuroimaging.

  20. Probabilistic multiple sclerosis lesion classification based on modeling regional intensity variability and local neighborhood information.

    PubMed

    Harmouche, Rola; Subbanna, Nagesh K; Collins, D Louis; Arnold, Douglas L; Arbel, Tal

    2015-05-01

    In this paper, a fully automatic probabilistic method for multiple sclerosis (MS) lesion classification is presented, whereby the posterior probability density function over healthy tissues and two types of lesions (T1-hypointense and T2-hyperintense) is generated at every voxel. During training, the system explicitly models the spatial variability of the intensity distributions throughout the brain by first segmenting it into distinct anatomical regions and then building regional likelihood distributions for each tissue class based on multimodal magnetic resonance image (MRI) intensities. Local class smoothness is ensured by incorporating neighboring voxel information in the prior probability through Markov random fields. The system is tested on two datasets from real multisite clinical trials consisting of multimodal MRIs from a total of 100 patients with MS. Lesion classification results based on the framework are compared with and without the regional information, as well as with other state-of-the-art methods against the labels from expert manual raters. The metrics for comparison include Dice overlap, sensitivity, and positive predictive rates for both voxel and lesion classifications. Statistically significant improvements in Dice values ( ), for voxel-based and lesion-based sensitivity values ( ), and positive predictive rates ( and respectively) are shown when the proposed method is compared to the method without regional information, and to a widely used method [1]. This holds particularly true in the posterior fossa, an area where classification is very challenging. The proposed method allows us to provide clinicians with accurate tissue labels for T1-hypointense and T2-hyperintense lesions, two types of lesions that differ in appearance and clinical ramifications, and with a confidence level in the classification, which helps clinicians assess the classification results.

  1. 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.

  2. Comprehensive tissue processing strategy for quantitative proteomics of formalin-fixed multiple sclerosis lesions.

    PubMed

    Ly, Linda; Barnett, Michael H; Zheng, Yuan Z; Gulati, Twishi; Prineas, John W; Crossett, Ben

    2011-10-07

    Formalin-fixed (FF) autopsy tissue comprises the bulk of existing Multiple Sclerosis (MSc) pathology archives, providing a rich pool of material for biomarker discovery and disease characterization. Here, we present the development of a heat-induced extraction protocol for the proteomic analysis of FF brain tissue, its application to the study of lesion remyelination and its failure in MSc. A 4-round extraction strategy was optimized using FF tissue leading to a 35% increase in the number of proteins identified compared to a single extraction; and a 65% increase in proteins identified with ≥4 peptides. Histological staining of sections with oil red O and luxol fast blue-periodic acid Schiff, required to characterize MSc lesions was found to have minimal effect on LC-MS/MS. The application of the optimized protocol to chronic demyelinated and remyelinated FF MSc lesions and the adjacent periplaque white matter, isolated through laser guided manual dissection from 3 patients, identified 428 unique proteins (0.2% FDR) using LC-MS/MS. Comparison of the lesion types using iTRAQ and 2-D LC-MS/MS revealed 82 differentially expressed proteins. Protein quantitation by iTRAQ and spectral counting was well-correlated (r(s)= 0.7653; p < 10(-30)). The data generated from this work illustrates the scope of the methodology and provides insights into the pathogenesis of MSc and remyelination.

  3. 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.

  4. A massive lesion detection algorithm in mammography.

    PubMed

    Fauci, Francesco; Raso, Giuseppe; Magro, Rosario; Forni, Giustina; Lauria, Adele; Bagnasco, Stefano; Cerello, Piergiorgio; Cheran, Sorin C; Lopez Torres, Ernesto; Bellotti, Robero; Carlo, Francesco De; Gargano, Gianfranco; Tangaro, Sonia; Mitri, Ivan De; Nunzio, Giorgio De; Cataldo, Rossella

    A new algorithm for massive lesion detection in mammography is presented. The algorithm consists in three main steps: 1) reduction of the dimension of the image to be processed through the identification of regions of interest (roi) as candidates for massive lesions; 2) characterization of the RoI by means of suitable feature extraction; 3) pattern classification through supervised neural networks. Suspect regions are detected by searching for local maxima of the pixel grey level intensity. A ring of increasing radius, centered on a maximum, is considered until the mean intensity in the ring decreases to a defined fraction of the maximum. The ROIS thus obtained are described by average, variance, skewness and kurtosis of the intensity distributions at different fractions of the radius. A neural network approach is adopted to classify suspect pathological and healthy pattern. The software has been designed in the framework of the INFN (Istituto Nazionale Fisica Nucleare) research project GPCALMA (Grid Platform for Calma) which recruits physicists and radiologists from different Italian Research Institutions and hospitals to develop software for breast cancer detection.

  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. Visual discrimination modeling of lesion detectability

    NASA Astrophysics Data System (ADS)

    Johnson, Jeffrey P.; Lubin, Jeffrey; Nafziger, John S.; Chakraborty, Dev P.

    2002-04-01

    The Sarnoff JNDmetrix visual discrimination model (VDM) was applied to predict human psychophysical performance in the detection of simulated mammographic lesions. Contrast thresholds for the detection of synthetic Gaussian masses on mean backgrounds and simulated mammographic backgrounds were measured in two-alternative, forced-choice (2AFC) trials. Experimental thresholds for 2-D Gaussian signal detection decreased with increasing signal size on mean backgrounds and on 1/f3 filtered noise images presented with identical (paired) backgrounds. For 2AFC presentations of different (unpaired) filtered noise backgrounds, detection thresholds increased with increasing signal diameter, consistent with a decreasing signal-to-noise ratio. Thresholds for mean and paired filtered noise backgrounds were used to calibrate a new low-pass, spatial-frequency channel in the VDM. The calibrated VDM was able to predict accurate detection thresholds for Gaussian signals on mean and paired 1/f3 filtered noise backgrounds. To simulate noise-limited detection thresholds for unpaired backgrounds, an approach is outlined for the development of a VDM-based model observer based on statistical decision theory.

  7. Automatic white matter lesion segmentation using an adaptive outlier detection method.

    PubMed

    Ong, Kok Haur; Ramachandram, Dhanesh; Mandava, Rajeswari; Shuaib, Ibrahim Lutfi

    2012-07-01

    White matter (WM) lesions are diffuse WM abnormalities that appear as hyperintense (bright) regions in cranial magnetic resonance imaging (MRI). WM lesions are often observed in older populations and are important indicators of stroke, multiple sclerosis, dementia and other brain-related disorders. In this paper, a new automated method for WM lesions segmentation is presented. In the proposed method, the presence of WM lesions is detected as outliers in the intensity distribution of the fluid-attenuated inversion recovery (FLAIR) MR images using an adaptive outlier detection approach. Outliers are detected using a novel adaptive trimmed mean algorithm and box-whisker plot. In addition, pre- and postprocessing steps are implemented to reduce false positives attributed to MRI artifacts commonly observed in FLAIR sequences. The approach is validated using the cranial MRI sequences of 38 subjects. A significant correlation (R=0.9641, P value=3.12×10(-3)) is observed between the automated approach and manual segmentation by radiologist. The accuracy of the proposed approach was further validated by comparing the lesion volumes computed using the automated approach and lesions manually segmented by an expert radiologist. Finally, the proposed approach is compared against leading lesion segmentation algorithms using a benchmark dataset.

  8. MRI phenotypes based on cerebral lesions and atrophy in patients with multiple sclerosis.

    PubMed

    Tauhid, Shahamat; Neema, Mohit; Healy, Brian C; Weiner, Howard L; Bakshi, Rohit

    2014-11-15

    While disease categories (i.e. clinical phenotypes) of multiple sclerosis (MS) are established, there remains MRI heterogeneity among patients within those definitions. MRI-defined lesions and atrophy show only moderate inter-correlations, suggesting that they represent partly different processes in MS. We assessed the ability of MRI-based categorization of cerebral lesions and atrophy in individual patients to identify distinct phenotypes. We studied 175 patients with MS [age (mean ± SD) 42.7 ± 9.1 years, 124 (71%) women, Expanded Disability Status (EDSS) score 2.5 ± 2.3, n = 18 (10%) clinically isolated demyelinating syndrome (CIS), n=115 (66%) relapsing-remitting (RR), and n = 42 (24%) secondary progressive (SP)]. Brain MRI measures included T2 hyperintense lesion volume (T2LV) and brain parenchymal fraction (to assess whole brain atrophy). Medians were used to create bins for each parameter, with patients assigned a low or high severity score. Four MRI phenotype categories emerged: Type I = low T2LV/mild atrophy [n = 67 (38%); CIS = 14, RR = 47, SP = 6]; Type II = high T2LV/mild atrophy [n = 21 (12%); RR = 19, SP = 2]; Type III = low T2LV/high atrophy [n = 21 (12%); CIS = 4, RR = 16, SP = 1]; and Type IV = high T2LV/high atrophy [n = 66 (38%); RR = 33, S P = 33]. Type IV was the most disabled and was the only group showing a correlation between T2LV vs. BPF and MRI vs. EDSS score (all p < 0.05). We described MRI-categorization based on the relationship between lesions and atrophy in individual patients to identify four phenotypes in MS. Most patients have congruent extremes related to the degree of lesions and atrophy. However, many have a dissociation. Longitudinal studies will help define the stability of these patterns and their role in risk stratification. Copyright © 2014. Published by Elsevier B.V.

  9. Central role of Th2/Tc2 lymphocytes in pattern II multiple sclerosis lesions

    PubMed Central

    Planas, Raquel; Metz, Imke; Ortiz, Yaneth; Vilarrasa, Nuria; Jelčić, Ilijas; Salinas-Riester, Gabriela; Heesen, Christoph; Brück, Wolfgang; Martin, Roland; Sospedra, Mireia

    2015-01-01

    Objective Multiple sclerosis (MS) is a disease of the central nervous system with marked heterogeneity in several aspects including pathological processes. Based on infiltrating immune cells, deposition of humoral factors and loss of oligodendrocytes and/or myelin proteins, four lesion patterns have been described. Pattern II is characterized by antibody and complement deposition in addition to T-cell infiltration. MS is considered a T-cell-mediated disease, but until now the study of pathogenic T cells has encountered major challenges, most importantly the limited access of brain-infiltrating T cells. Our objective was to identify, isolate, and characterize brain-infiltrating clonally expanded T cells in pattern II MS lesions. Methods We used next-generation sequencing to identify clonally expanded T cells in demyelinating pattern II brain autopsy lesions, subsequently isolated these as T-cell clones from autologous cerebrospinal fluid and functionally characterized them. Results We identified clonally expanded CD8+ but also CD4+ T cells in demyelinating pattern II lesions and for the first time were able to isolate these as live T-cell clones. The functional characterization shows that T cells releasing Th2 cytokines and able to provide B cell help dominate the T-cell infiltrate in pattern II brain lesions. Interpretation Our data provide the first functional evidence for a putative role of Th2/Tc2 cells in pattern II MS supporting the existence of this pathogenic phenotype and questioning the protective role that is generally ascribed to Th2 cells. Our observations are important to consider for future treatments of pattern II MS patients. PMID:26401510

  10. Cellular distribution of glucose and monocarboxylate transporters in human brain white matter and multiple sclerosis lesions.

    PubMed

    Nijland, Philip G; Michailidou, Iliana; Witte, Maarten E; Mizee, Mark R; van der Pol, Susanne M A; van Het Hof, Bert; Reijerkerk, Arie; Pellerin, Luc; van der Valk, Paul; de Vries, Helga E; van Horssen, Jack

    2014-07-01

    To ensure efficient energy supply to the high demanding brain, nutrients are transported into brain cells via specific glucose (GLUT) and monocarboxylate transporters (MCT). Mitochondrial dysfunction and altered glucose metabolism are thought to play an important role in the progression of neurodegenerative diseases, including multiple sclerosis (MS). Here, we investigated the cellular localization of key GLUT and MCT proteins in human brain tissue of non-neurological controls and MS patients. We show that in control brain tissue GLUT and MCT proteins were abundantly expressed in a variety of central nervous system cells, particularly in microglia and endothelial cells. In active MS lesions, GLUTs and MCTs were highly expressed in infiltrating leukocytes and reactive astrocytes. Astrocytes manifest increased MCT1 staining and maintain GLUT expression in inactive lesions, whereas demyelinated axons exhibit significantly reduced GLUT3 and MCT2 immunoreactivity in inactive lesions. Finally, we demonstrated that the co-transcription factor peroxisome proliferator-activated receptor gamma co-activator 1-alpha (PGC-1α), an important protein involved in energy metabolism, is highly expressed in reactive astrocytes in active MS lesions. Overexpression of PGC-1α in astrocyte-like cells resulted in increased production of several GLUT and MCT proteins. In conclusion, we provide for the first time a comprehensive overview of key nutrient transporters in white matter brain samples. Moreover, our data demonstrate an altered expression of these nutrient transporters in MS brain tissue, including a marked reduction of axonal GLUT3 and MCT2 expression in chronic lesions, which may impede efficient nutrient supply to the hypoxic demyelinated axons thereby contributing to the ongoing neurodegeneration in MS.

  11. 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.

  12. 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.

  13. 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.

  14. 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. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. 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.

  16. Brain MRI lesions and atrophy are associated with employment status in patients with multiple sclerosis.

    PubMed

    Tauhid, Shahamat; Chu, Renxin; Sasane, Rahul; Glanz, Bonnie I; Neema, Mohit; Miller, Jennifer R; Kim, Gloria; Signorovitch, James E; Healy, Brian C; Chitnis, Tanuja; Weiner, Howard L; Bakshi, Rohit

    2015-11-01

    Multiple sclerosis (MS) commonly affects occupational function. We investigated the link between brain MRI and employment status. Patients with MS (n = 100) completed a Work Productivity and Activity Impairment (WPAI) (general health version) survey measuring employment status, absenteeism, presenteeism, and overall work and daily activity impairment. Patients "working for pay" were considered employed; "temporarily not working but looking for work," "not working or looking for work due to age," and "not working or looking for work due to disability" were considered not employed. Brain MRI T1 hypointense (T1LV) and T2 hyperintense (T2LV) lesion volumes were quantified. To assess lesional destructive capability, we calculated each subject's ratio of T1LV to T2LV (T1/T2). Normalized brain parenchymal volume (BPV) assessed brain atrophy. The mean (SD) age was 45.5 (9.7) years; disease duration was 12.1 (8.1) years; 75 % were women, 76 % were relapsing-remitting, and 76 % were employed. T1LV, T1/T2, Expanded Disability Status Scale (EDSS) scores, and activity impairment were lower and BPV was higher in the employed vs. not employed group (Wilcoxon tests, p < 0.05). Age, disease duration, MS clinical subtype, and T2LV did not differ between groups (p > 0.05). In multivariable logistic regression modeling, adjusting for age, sex, and disease duration, higher T1LV predicted a lower chance of employment (p < 0.05). Pearson correlations showed that EDSS was associated with activity impairment (p < 0.05). Disease duration, age, and MRI measures were not correlated with activity impairment or other WPAI outcomes (p > 0.05). We report a link between brain atrophy and lesions, particularly lesions with destructive potential, to MS employment status.

  17. Complement is activated in progressive multiple sclerosis cortical grey matter lesions.

    PubMed

    Watkins, Lewis M; Neal, James W; Loveless, Sam; Michailidou, Iliana; Ramaglia, Valeria; Rees, Mark I; Reynolds, Richard; Robertson, Neil P; Morgan, B Paul; Howell, Owain W

    2016-06-22

    The symptoms of multiple sclerosis (MS) are caused by damage to myelin and nerve cells in the brain and spinal cord. Inflammation is tightly linked with neurodegeneration, and it is the accumulation of neurodegeneration that underlies increasing neurological disability in progressive MS. Determining pathological mechanisms at play in MS grey matter is therefore a key to our understanding of disease progression. We analysed complement expression and activation by immunocytochemistry and in situ hybridisation in frozen or formalin-fixed paraffin-embedded post-mortem tissue blocks from 22 progressive MS cases and made comparisons to inflammatory central nervous system disease and non-neurological disease controls. Expression of the transcript for C1qA was noted in neurons and the activation fragment and opsonin C3b-labelled neurons and glia in the MS cortical and deep grey matter. The density of immunostained cells positive for the classical complement pathway protein C1q and the alternative complement pathway activation fragment Bb was significantly increased in cortical grey matter lesions in comparison to control grey matter. The number of cells immunostained for the membrane attack complex was elevated in cortical lesions, indicating complement activation to completion. The numbers of classical (C1-inhibitor) and alternative (factor H) pathway regulator-positive cells were unchanged between MS and controls, whilst complement anaphylatoxin receptor-bearing microglia in the MS cortex were found closely apposed to cortical neurons. Complement immunopositive neurons displayed an altered nuclear morphology, indicative of cell stress/damage, supporting our finding of significant neurodegeneration in cortical grey matter lesions. Complement is activated in the MS cortical grey matter lesions in areas of elevated numbers of complement receptor-positive microglia and suggests that complement over-activation may contribute to the worsening pathology that underlies the

  18. TROY and LINGO-1 expression in astrocytes and macrophages/microglia in multiple sclerosis lesions.

    PubMed

    Satoh, J; Tabunoki, H; Yamamura, T; Arima, K; Konno, H

    2007-02-01

    Nogo constitutes a family of neurite outgrowth inhibitors contributing to a failure of axonal regeneration in the adult central nervous system (CNS). Nogo-A is expressed exclusively on oligodendrocytes where Nogo-66 segment binds to Nogo receptor (NgR) expressed on neuronal axons. NgR signalling requires a coreceptor p75(NTR) or TROY in combination with an adaptor LINGO-1. To characterize the cell types expressing the NgR complex in the human CNS, we studied demyelinating lesions of multiple sclerosis (MS) brains by immunohistochemistry. TROY and LINGO-1 were identified in subpopulations of reactive astrocytes, macrophages/microglia and neurones but not in oligodendrocytes. TROY was up-regulated, whereas LINGO-1 was reduced in MS brains by Western blot. These results suggest that the ternary complex of NgR/TROY/LINGO-1 expressed on astrocytes, macrophages/microglia and neurones, by interacting with Nogo-A on oligodendrocytes, might modulate glial-neuronal interactions in demyelinating lesions of MS.

  19. 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.

  20. 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.

  1. Tracking the Evolution of Cerebral Gadolinium-Enhancing Lesions to Persistent T1 Black Holes in Multiple Sclerosis: Validation of a Semiautomated Pipeline.

    PubMed

    Andermatt, Simon; Papadopoulou, Athina; Radue, Ernst-Wilhelm; Sprenger, Till; Cattin, Philippe

    2017-09-01

    Some gadolinium-enhancing multiple sclerosis (MS) lesions remain T1-hypointense over months ("persistent black holes, BHs") and represent areas of pronounced tissue loss. A reduced conversion of enhancing lesions to persistent BHs could suggest a favorable effect of a medication on tissue repair. However, the individual tracking of enhancing lesions can be very time-consuming in large clinical trials. We created a semiautomated workflow for tracking the evolution of individual MS lesions, to calculate the proportion of enhancing lesions becoming persistent BHs at follow-up. Our workflow automatically coregisters, compares, and detects overlaps between lesion masks at different time points. We tested the algorithm in a data set of Magnetic Resonance images (1.5 and 3T; spin-echo T1-sequences) from a phase 3 clinical trial (n = 1,272), in which all enhancing lesions and all BHs had been previously segmented at baseline and year 2. The algorithm analyzed the segmentation masks in a longitudinal fashion to determine which enhancing lesions at baseline turned into BHs at year 2. Images of 50 patients (192 enhancing lesions) were also reviewed by an experienced MRI rater, blinded to the algorithm results. In this MRI data set, there were no cases that could not be processed by the algorithm. At year 2, 417 lesions were classified as persistent BHs (417/1,613 = 25.9%). The agreement between the rater and the algorithm was > 98%. Due to the semiautomated procedure, this algorithm can be of great value in the analysis of large clinical trials, when a rater-based analysis would be time-consuming. Copyright © 2017 by the American Society of Neuroimaging.

  2. 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.

  3. Interferon β treatment for multiple sclerosis has a graduated effect on MRI enhancing lesions according to their size and pathology

    PubMed Central

    Filippi, M; Rovaris, M; Capra, R; Gasperini, C; Prandini, F; Martinelli, V; Horsfield, M; Bastianello, S; Sormani, M; Pozzilli, C; Comi, G

    1999-01-01

    OBJECTIVE—The ability of recombinant human interferon β-1a (rh-IFN β-1a) to suppress multiple sclerosis activity, evaluated from MRI, was assessed across a range of lesions enhancing at different gadolinium-DTPA (Gd) doses and with different sizes.
METHODS—Every 4 weeks, standard dose (Sd; 0.1 mmol/kg Gd) and triple dose (Td; 0.3 mmol/kgGd) MRI were obtained from 18 patients with relapsing-remitting multiple sclerosis for 3 months before and 4 months after starting treatment with 44 µg rh-IFN β-1a subcutaneously, once a week.
RESULTS—The total numbers of enhancing lesions were 145 and 126 on Sd scans and 278 and 192 on the Td scans obtained before and after treatment. The introduction of treatment decreased, on average, the rate of appearance of new enhancing lesions seen on Sd and Td scans by 37% (p<0.001). Treatment effects on new enhancing lesions seen on Td scans was, on average, 28% higher than on those seen on Sd scans. The distribution of lesion sizes on Td scans changed significantly during the treatment period (p=0.05), due to a marked decrease in the number of small lesions.
CONCLUSIONS— The effect of 44 µg rh-IFN β-1a in reducing multiple sclerosis disease activity, as monitored by Gd enhanced MRI, is not homogeneous, but graduated according to the pathological characteristics and size of the lesions.

 PMID:10449565

  4. 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. © 2013 Elsevier B.V. All rights reserved.

  5. Cardiovascular risk factors are associated with increased lesion burden and brain atrophy in multiple sclerosis.

    PubMed

    Kappus, Natalie; Weinstock-Guttman, Bianca; Hagemeier, Jesper; Kennedy, Cheryl; Melia, Rebecca; Carl, Ellen; Ramasamy, Deepa P; Cherneva, Mariya; Durfee, Jacqueline; Bergsland, Niels; Dwyer, Michael G; Kolb, Channa; Hojnacki, David; Ramanathan, Murali; Zivadinov, Robert

    2016-02-01

    Cardiovascular (CV) risk factors have been associated with changes in clinical outcomes in patients with multiple sclerosis (MS). To investigate the frequency of CV risks in patients with MS and their association with MRI outcomes. In a prospective study, 326 patients with relapsing-remitting MS and 163 patients with progressive MS, 61 patients with clinically isolated syndrome (CIS) and 175 healthy controls (HCs) were screened for CV risks and scanned on a 3T MRI scanner. Examined CV risks included hypertension, heart disease, smoking, overweight/obesity and type 1 diabetes. MRI measures assessed lesion volumes (LVs) and brain atrophy. Association between individual or multiple CV risks and MRI outcomes was examined adjusting for age, sex, race, disease duration and treatment status. Patients with MS showed increased frequency of smoking (51.7% vs 36.5%, p = 0.001) and hypertension (33.9% vs 24.7%, p=0.035) compared with HCs. In total, 49.9% of patients with MS and 36% of HCs showed ≥ 2 CV risks (p = 0.003), while the frequency of ≥ 3 CV risks was 18.8% in the MS group and 8.6% in the HCs group (p = 0.002). In patients with MS, hypertension and heart disease were associated with decreased grey matter (GM) and cortical volumes (p < 0.05), while overweight/obesity was associated with increased T1-LV (p < 0.39) and smoking with decreased whole brain volume (p = 0.049). Increased lateral ventricle volume was associated with heart disease (p = 0.029) in CIS. Patients with MS with one or more CV risks showed increased lesion burden and more advanced brain atrophy. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  6. New hypointense lesions on MRI in relapsing-remitting multiple sclerosis patients.

    PubMed

    Wagner, S; Adams, H; Sobel, D F; Slivka, L S; Sipe, J C; Romine, J S; Koziol, J A

    2000-01-01

    Preliminary observational studies with multiple sclerosis (MS) patients have reported strong correlations between an increase in hypointense lesion load (black holes) on T1-weighted spin echo images, and an increase in disability. We assessed the relationship of hypointense lesions to the clinical course of disease among 50 relapsing-remitting MS patients in the controlled setting of a randomized clinical trial. Fifty patients with relapsing-remitting disease were enrolled in a randomized double-blind two-arm (cladribine vs. placebo) clinical trial of 1-year duration. All patients had monthly clinical evaluations and MRIs over the course of the trial. Multivariate techniques were used to identify predictors of clinical severity from information on exacerbations, MRIs, baseline clinical parameters, and demographics. At baseline, clinical severity is weakly related to counts of black holes, with rank correlations between counts and clinical scores (EDSS and SNRS) of absolute magnitude 0.3. Rates of appearance of new black holes over the course of the trial are higher for patients with more severe disease at baseline (EDSS > or = 4) than for the less severe patients. Changes in clinical severity over the course of the trial are best predicted by baseline neurologic scores and numbers of exacerbations, with black holes adding no further improvement in prediction. Numbers of exacerbations seem more critical to short-term clinical outcomes in relapsing-remitting MS, as reflected by patients' clinical scores, rather than black holes. Various imaging methods and MRI indices capture complementary information relating to MS disease processes. The determination of which processes are affected by different drugs should lead to more effective treatment of MS patients. Copyright 2000 S. Karger AG, Basel.

  7. Dealing with excess of zeros in the statistical analysis of magnetic resonance imaging lesion count in multiple sclerosis.

    PubMed

    Francois, Mercier; Peter, Chin; Gordon, Francis

    2012-01-01

    Lesion count observed on brain magnetic resonance imaging scan is a common end point in phase 2 clinical trials evaluating therapeutic treatment in relapsing remitting multiple sclerosis (MS). This paper compares the performances of Poisson, zero-inflated poisson (ZIP), negative binomial (NB), and zero-inflated NB (ZINB) mixed-effects regression models in fitting lesion count data in a clinical trial evaluating the efficacy and safety of fingolimod in comparison with placebo, in MS. The NB and ZINB models prove to be superior to the Poisson and ZIP models. We discuss the advantages and limitations of zero-inflated models in the context of MS treatment.

  8. 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.

  9. Intracortical inhibition abnormality during the remission phase of multiple sclerosis is related to upper limb dexterity and lesions.

    PubMed

    Nantes, Julia C; Zhong, Jidan; Holmes, Scott A; Whatley, Benjamin; Narayanan, Sridar; Lapierre, Yves; Arnold, Douglas L; Koski, Lisa

    2016-02-01

    The impact of inhibitory cortical activity on motor impairment of people with relapsing-remitting multiple sclerosis (RRMS) has not been fully elucidated despite its relevance to neurorehabilitation. The present study assessed the extent to which transcranial magnetic stimulation (TMS)-based metrics of intracortical inhibition are related to motor disability and brain damage. Participants included forty-three persons with RRMS in the remitting phase and twenty-nine healthy controls. We stimulated the dominant hemisphere and recorded from the dominant hand to assess short-interval intracortical inhibition (SICI) and cortical silent period (CSP) duration. Disability was evaluated with the Multiple Sclerosis Functional Composite (MSFC). Regional cortical thickness and lesion volume were measured. RRMS participants with dominant upper limb dexterity impairments had prolonged CSP, but equivalent SICI, compared to participants with preserved function. CSP was not related to walking or cognitive performance. Higher normalized lesion volume correlated with longer CSP duration. When adjusting for normalized lesion volume, longer CSP significantly predicted worse dominant upper extremity impairment. High intracortical inhibition possibly contributes to (or prevents remission from) motor impairment. Lesions may be associated with intracortical inhibition shifts. CSP duration and lesion burden should be considered when developing interventions aiming to mitigate motor impairment. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  10. 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.

  11. Incidental Breast Lesions Detected on Computed Thorax Tomography

    PubMed Central

    Poyraz, Necdet; Emlik, Ganime Dilek; Keskin, Suat; Kalkan, Havva

    2015-01-01

    Objective Although mammography is the primary imaging method of the breast, incidental benign and malignant breast lesions are increasingly being detected on computed tomographies (CTs) performed to detect different pathologies. Therefore, the detection and accurate identification of these lesions is important. In this study, we aimed to evaluate the frequency, morphological features, and results of incidental breast lesions on CTs performed for the detection of extramammarian pathologies. Materials and Methods Incidental breast lesions on CTs performed in our department between 2011 and 2013 were evaluated. Patients who had previously diagnosed breast lesions were excluded from the study. The inclusion criteria were histopathologic diagnose and being followed-up for at least 2 years. Results The study population consisted of 33 women whose mean age was 55±1.38 (37–78) years. Of the 33 women, 12 (36%) had malignant and 21 (64%) had benign or normal findings. The most common malignant lesion was invasive ductal carcinoma, and the most common benign lesion was fibroadenoma. Ill-defined contour and lymphadenopathy in malignant lesions and well-defined contour in benign lesions were the most important CT findings. Conclusion Breast must be carefully evaluated if it is included in the scans. An accurate report of breast lesions gives an opportunity for early diagnosis and treatment.

  12. 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.

  13. Evaluation of scintillation cameras by spherical lesion detectability.

    PubMed

    Shinohara, H; Koga, Y

    1980-12-01

    The lesion detectability with a scintillation camera as a function of count density was determined for the four spherical cold lesions with diameter 0.9-2.5 cm (in square root 2 step) within a uniform background activity. It can be seen from the curves that the lesion detectability increases with an increase in count density until 2 kcounts/cm2, however it does not appreciably improve for count densities above 2 kcounts/cm2. The curves also show that, for a giving count density, the lesion detectability decreases as the lesion size or object contrast decreases. From these curves minimum count density required for recognition of each cold lesion is deduced. This value is applied to the evaluation of scintillation camera system.

  14. Lesion remyelinating activity of GSK239512 versus placebo in patients with relapsing-remitting multiple sclerosis: a randomised, single-blind, phase II study.

    PubMed

    Schwartzbach, Caryl J; Grove, Richard A; Brown, Robert; Tompson, Debra; Then Bergh, Florian; Arnold, Douglas L

    2017-02-01

    Histamine H3 receptor blockade may enhance lesion remyelination in multiple sclerosis (MS). The efficacy (using a magnetic resonance imaging marker of myelination, magnetisation transfer ratio [MTR]), safety and pharmacokinetics of GSK239512, a potent and brain penetrant H3 receptor antagonist/inverse agonist on lesion remyelination in relapsing-remitting MS (RRMS) were assessed. This was a phase II, randomised, parallel-group, placebo-controlled, double-blind (sponsor-unblinded), international, multicentre study (NCT01772199). Patients aged 18-50 with RRMS, receiving intramuscular interferon-β1a or glatiramer acetate, were randomised 1:1 to once-daily oral GSK239512 or placebo, up-titrated over 4-5 weeks to a maximum tolerable dose up to 80 µg and maintained until Week 48. The co-primary endpoints were mean changes in post-lesion MTR in gadolinium-enhanced (GdE) or Delta-MTR defined lesions from pre-lesion values. Adverse events (AE) and withdrawals were monitored. Of the 131 patients randomised, 114 patients completed the study (GSK239512, n = 51; placebo, n = 63) and 27 (GSK239512) and 28 (placebo) patients contributed lesions to the primary analysis. GSK239512 was associated with positive effect sizes of 0.344 [90% confidence interval (CI) 0.018, 0.671] and 0.243 (90% CI -0.112, 0.598) for adjusted mean changes in the normalised MTR for GdE and Delta-MTR lesions, respectively. The overall incidence of AEs was similar between GSK239512 and placebo during the treatment phase although some AEs including insomnia were more common with GSK239512, particularly during the titration period. A small but positive effect of GSK239512 on remyelination was observed. MTR assessment represents a promising method for detecting lesion remyelination in RRMS.

  15. 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.

  16. White matter and lesion T1 relaxation times increase in parallel and correlate with disability in multiple sclerosis.

    PubMed

    Parry, A; Clare, S; Jenkinson, M; Smith, S; Palace, J; Matthews, P M

    2002-09-01

    Previous studies have established the clinical relevance of hypointense lesions ("black holes") on T1-weighted MRI as a surrogate marker for pathological change [36]. In contrast to measuring the volume of "black holes", the direct measurement of T1 values allows an objective assessment of the changes contributing to hypointensity both in the focal lesions and in the normal appearing white matter (NAWM). The aims of this study were first, to determine the relationship between T1 values in the NAWM and in discrete lesions, second, to test the relationship between white matter T1 changes and measures of disability and third, to determine whether pathology leading to T1 change occurred in thalamic grey matter of patients with multiple sclerosis. 24 patients with clinically definite multiple sclerosis (13 with relapsing-remitting multiple sclerosis and 11 with secondary progressive multiple sclerosis) and 11 controls participated. White matter T1 histograms and mean T1 values for the thalamus were generated from whole brain T1 relaxation time maps measured using a novel echo-planar imaging based MRI sequence at 3Tesla. Tissue segmentation based on T2- and T1-weighted images allowed independent study of changes in lesions and NAWM. White matter T1 histograms from the patient group showed a reduced peak height and a shift towards higher T1 values (p = 0.028) relative to controls. The mean thalamic T1 was greater for secondary progressive patients than for healthy controls (p = 0.03). Mean white matter T1 values correlated significantly with disability (r = 0.48, p = 0.02). The mean T1 value in the T1-hypointense lesions correlated strongly with the mean T1 value in the NAWM (r = 0.80, p < 0.001). No significant relationship was found between mean white matter T1 value and cerebral volume (r = -0.23, p = 0.31). The T1 measurements extend previous observations suggesting that changes in the NAWM occur in parallel with pathology in lesions of MS. T1 measurements of either

  17. Lesion conspicuity and AFROC performance in pulmonary nodule detection

    NASA Astrophysics Data System (ADS)

    Manning, David; Ethell, Susan C.

    2002-04-01

    A test bank of verified chest radiographs was compiled for visual search experiments. The purpose was to investigate human performance in the detection of significant pulmonary nodules. Synthesized nodules supplemented native lesions. The distribution of all the lesions in the lung fields was consistent with the naturally occurring locations of these features. A measure of the physical characteristics of the lesions was derived in order to approximate the conspicuity of the synthetic to the natural nodules. The measure of conspicuity was given as (chi) =Tan(theta-1)S/N where (theta) is the maximum slope angle to the edge of the lesion profile, S is the mean pixel value of the lesion profile taken in four orientations, and N is the mean background pixel value taken in four orientations over one lesion dimension adjacent to the lesion. The variation in (chi) for each of the 81 lesions (46 natural and 35 synthetic) was plotted against SNR and edge angle. The influence of edge angle on the resulting (chi) values was more powerful than SNR for all the lesions in this experiment. Although there was an overall significant difference in (chi) values (p=0.015), observers were unable to distinguish synthetic from native lesions. Observer performance in nodule detection was measured by AFROC and supplemented with visual search recording. Correlation of AFROC scores and the (chi) values has shown no overall relationship (R2=0.0452) and this surprising result may be partly explained through inspection of the visual search recordings.

  18. A comparison of phase imaging and quantitative susceptibility mapping in the imaging of multiple sclerosis lesions at ultrahigh field.

    PubMed

    Cronin, Matthew John; Wharton, Samuel; Al-Radaideh, Ali; Constantinescu, Cris; Evangelou, Nikos; Bowtell, Richard; Gowland, Penny Anne

    2016-06-01

    The aim of this study was to compare the use of high-resolution phase and QSM images acquired at ultra-high field in the investigation of multiple sclerosis (MS) lesions with peripheral rings, and to discuss their usefulness for drawing inferences about underlying tissue composition. Thirty-nine Subjects were scanned at 7 T, using 3D T 2*-weighted and T 1-weighted sequences. Phase images were then unwrapped and filtered, and quantitative susceptibility maps were generated using a thresholded k-space division method. Lesions were compared visually and using a 1D profiling algorithm. Lesions displaying peripheral rings in the phase images were identified in 10 of the 39 subjects. Dipolar projections were apparent in the phase images outside of the extent of several of these lesions; however, QSM images showed peripheral rings without such projections. These projections appeared ring-like in a small number of phase images where no ring was observed in QSM. 1D profiles of six well-isolated example lesions showed that QSM contrast corresponds more closely to the magnitude images than phase contrast. Phase images contain dipolar projections, which confounds their use in the investigation of tissue composition in MS lesions. Quantitative susceptibility maps correct these projections, providing insight into the composition of MS lesions showing peripheral rings.

  19. Association of cognitive impairment and lesion volumes in multiple sclerosis--a MRI study.

    PubMed

    Yildiz, Murat; Tettenborn, Barbara; Radue, Ernst-Wilhelm; Bendfeldt, Kerstin; Borgwardt, Stefan

    2014-12-01

    Cognitive impairment (CI) can be demonstrated in 40-65% of multiple sclerosis (MS) patients, sometimes starting from the early stages of the disease. The objective of this study was a community-based investigation of FLAIR-hyperintense lesion volumes (LV) and their association with CI in patients with relapsing remitting (RR) MS. The neurocognitive assessment was conducted with the brief cognitive screening instrument, MUSIC. Magnetic resonance imaging (MRI) scans were obtained with a 1.5 Tesla Sigma Magnetom MRI scanner. We conducted a stepwise multiple regression analysis to assess the relative contribution of the main clinical, demographic and MRI-variables in predicting cognitive impairment. We recruited 78 patients with RRMS. The mean MUSIC score was 20.6 ± 5.4. Forty five percent of patients (n = 35, mean score 15.1 ± 3.3) had CI and 55% (n = 43, mean score 24.4 ± 2.5) had no sign of CI. In the correlation analysis of the MUSIC subtests only the interference test correlated negatively with the LV (r = -0.23). Multivariate linear regression analysis using MUSIC as the dependent continuous variable revealed LV and disability severity as independent factors associated with MUSIC (p value of the regression model < 0.001; adjusted R-square = 0.11). The results of the present study suggest an association between white matter damage and CI in MS. We could demonstrate an association between attention difficulties and the LV in MS patients. ClinicalTrials.gov Identifier: NCT01250665 and NCT01250678. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. [Sex-related differences in atrophy and lesion load in multiple sclerosis patients].

    PubMed

    Rojas, J I; Patrucco, L; Besada, C; Funes, J; Cristiano, E

    2013-09-01

    Previous studies showed gender-associated clinical and MRI differences in multiple sclerosis (MS) evolution. However, only few studies were done with non conventional MRI techniques and no one was done in a South American MS population. The aim of this study was to investigate gender differences according to nonconventional MRI measures in patients with MS from Buenos Aires, Argentina. Relapsing-remitting MS patients (RRMS) with at least 6 years of follow up and an MRI at onset and at 6 years were included. Patients were assessed using nonconventional MRI measures: total brain volume (TBV), neocortical grey brain volume (GBV), white brain volume (WBV), lesion load (LL), % of brain volume change between onset and year 6 (% BVC) and regional brain volume change. Gender-related MRI differences were investigated using general linear model analysis. The 45 patients were included (25 female). Mean follow up time was 7.3 ± 0.2 years. No differences in age, EDSS at onset, DMD treatment, TBV, GBV, WBV neither LL were found between gender at baseline. Six years later, males showed a decrease in TBV (P=.002) and GBV (P ≤ 0.001) and an increase in LL (P=.02) and % BVC (P<.001) vs. females. Female patients showed a decrease in the volume of frontal subcortical region. This is the first study showing differences in brain volume changes between gender in MS patients from South America. Future studies will confirm our initial findings. Copyright © 2012 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

  1. Balo’s concentric lesions with concurrent features of Schilder’s disease in relapsing multiple sclerosis: neuropathological findings

    PubMed Central

    Ramsay, David

    2016-01-01

    Atypical inflammatory demyelinating syndromes are rare neurological diseases that differ from multiple sclerosis (MS), owing to unusual clinicoradiological and pathological findings, and poor responses to treatment. The distinction between them and the criteria for their diagnoses are poorly defined due to the lack of advanced research studies. Balo’s concentric sclerosis (BCS) and Schilder’s disease (SD) are two of these syndromes and can present as monophasic or in association with chronic MS. Both variants are difficult to distinguish when they present in acute stages. We describe an autopsy case of middle-aged female with a chronic history of MS newly relapsed with atypical demyelinating lesions, which showed concurrent features of BCS and SD. We also describe the neuropathological findings, and discuss the overlapping features between these two variants. PMID:28210570

  2. Resecting without detecting the lesion in extratemporal lobe epilepsy?

    PubMed

    Henry, Thomas R

    2014-03-18

    Nonlesional extratemporal lobe epilepsy (ETLE) often persists following resection of the site of ictal onset, localized with definitive intracranial EEG recordings.(1,2) In lesional ETLE, however, lesionectomy with resection of a single electrophysiologically defined ictal onset (ictogenic) zone often stops seizures immediately and permanently.(1,2) In temporal lobe epilepsy (TLE), a single ictogenic site can be resected, either with an accompanying lesion or in the absence of an MRI-detected lesion, and is a highly efficacious epilepsy therapy.(2) Efforts to increase surgical efficacy in nonlesional ETLE have focused on localization by functional imaging to substitute for lesion localization by structural imaging.

  3. Automated White Matter Hyperintensity Detection in Multiple Sclerosis Using 3D T2 FLAIR

    PubMed Central

    Zhong, Yi; Wang, Ying; Kang, Yan; Haacke, E. Mark

    2014-01-01

    White matter hyperintensities (WMH) seen on T2WI are a hallmark of multiple sclerosis (MS) as it indicates inflammation associated with the disease. Automatic detection of the WMH can be valuable in diagnosing and monitoring of treatment effectiveness. T2 fluid attenuated inversion recovery (FLAIR) MR images provided good contrast between the lesions and other tissue; however the signal intensity of gray matter tissue was close to the lesions in FLAIR images that may cause more false positives in the segment result. We developed and evaluated a tool for automated WMH detection only using high resolution 3D T2 fluid attenuated inversion recovery (FLAIR) MR images. We use a high spatial frequency suppression method to reduce the gray matter area signal intensity. We evaluate our method in 26 MS patients and 26 age matched health controls. The data from the automated algorithm showed good agreement with that from the manual segmentation. The linear correlation between these two approaches in comparing WMH volumes was found to be Y = 1.04X + 1.74  (R2 = 0.96). The automated algorithm estimates the number, volume, and category of WMH. PMID:25136355

  4. 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.

  5. 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.

  6. The Central Vein Sign in Multiple Sclerosis Lesions Is Present Irrespective of the T2* Sequence at 3 T.

    PubMed

    Samaraweera, Amal P R; Clarke, Margareta A; Whitehead, Amy; Falah, Yasser; Driver, Ian D; Dineen, Robert A; Morgan, Paul S; Evangelou, Nikos

    2017-01-01

    Previous T2*-weighted magnetic resonance imaging (MRI) studies have used white matter lesion (WML) central veins to distinguish multiple sclerosis (MS) from its mimics. To be clinically applicable, the "central vein sign" needs to be detectable across different T2* sequences. Our objective was to determine if the central vein sign is reliably present in MS and absent in patients with ischemic small vessel disease (SVD) across different T2* sequences at 3T MRI. Ten patients with MS and 10 with SVD were each scanned on a 3 T Philips and GE scanner. The MRI protocol included 3-dimensional (3D) T2* GRE, T2* with high echo planar imaging (EPI) factor and susceptibility-weighted angiography (SWAN). Total WML numbers, central vein numbers, and proportion of WMLs with central veins were calculated using each sequence. Three blinded raters identified a subset of six WMLs with central veins to diagnose MS or SVD. Irrespective of the sequence, MS patients were identified based on a higher proportion of WMLs with central veins. This proportion was dependent on the T2* sequence used. T2* with high EPI allowed the highest median proportion (69.6%) in MS patients; 6.1% in SVD patients (P < .0004). Rater reproducibility varied depending on the T2* sequence used. T2* with high EPI produced good agreement with the clinical diagnosis (Cohen's kappa range; .78-.89), as did SWAN imaging with some raters; ĸ = .69. The central vein sign can diagnose MS in the clinical setting of modern 3T scanners. However, variations in the T2* sequences need to be considered when defining a threshold for diagnosis. Copyright © 2016 by the American Society of Neuroimaging.

  7. [Correlation between demyelinating lesions and executive function decline in a sample of Mexican patients with multiple sclerosis].

    PubMed

    Aldrete Cortez, V R; Duriez-Sotelo, E; Carrillo-Mora, P; Pérez-Zuno, J A

    2013-09-01

    Multiple Sclerosis (MS) is characterised by several neurological symptoms including cognitive impairment, which has recently been the subject of considerable study. At present, evidence pointing to a correlation between lesion characteristics and specific cognitive impairment is not conclusive. To investigate the presence of a correlation between the characteristics of demyelinating lesions and performance of basic executive functions in a sample of MS patients. We included 21 adult patients with scores of 0 to 5 on the Kurtzke scale and no exacerbations of the disease in at least 3 months prior to the evaluation date. They completed the Stroop test and the Wisconsin Card Sorting Test (WCST). The location of the lesions was determined using magnetic resonance imaging (MRI) performed by a blinded expert in neuroimaging. Demyelinating lesions were more frequently located in the frontal and occipital lobes. The Stroop test showed that as cognitive demand increased on each of the sections in the test, reaction time and number of errors increased. On the WCST, 33.33% of patients registered as having moderate cognitive impairment. No correlation could be found between demyelinating lesion characteristics (location, size, and number) and patients' scores on the tests. Explanations of the causes of cognitive impairment in MS should examine a variety of biological, psychological, and social factors instead of focusing solely on demyelinating lesions. Copyright © 2012 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

  8. Progression of retinal ganglion cell loss in multiple sclerosis is associated with new lesions in the optic radiations.

    PubMed

    Klistorner, A; Graham, E C; Yiannikas, C; Barnett, M; Parratt, J; Garrick, R; Wang, C; You, Y; Graham, S L

    2017-08-10

    The mechanism of retinal ganglion cell and retinal nerve fiber layer loss in multiple sclerosis (MS) remains unknown. This study aimed to investigate the association between temporal retinal nerve fiber layer (tRNFL) thinning and disease activity in the brain determined by T2 lesions on magnetic resonance imaging (MRI). Fifty-five consecutive patients with relapsing-remitting MS and 25 controls were enrolled. All patients underwent annual optical coherence tomography and high-resolution MRI scans for tRNFL thickness and brain lesion volume analysis, respectively. Significant tRNFL thickness reduction was observed over the 3-year follow-up period at a relatively constant rate (1.02 μm/year). Thinning of tRNFL fibers was more prominent in younger patients (P = 0.01). The tRNFL loss was associated with new MRI lesions in the optic radiations (ORs). There was significantly greater tRNFL thinning in patients with new lesional activity in the ORs compared with patients with new lesions outside the ORs (P = 0.009). This study supports the notion that retrograde transneuronal degeneration caused by OR lesions might play a role in progressive retinal nerve fiber layer loss. In addition, the results of the study also indicate that the disease-related neurodegenerative changes in the retina start much earlier than the clinical diagnosis of MS. © 2017 EAN.

  9. Susceptibility-sensitive MRI of multiple sclerosis lesions and the impact of normal-appearing white matter changes.

    PubMed

    Wiggermann, Vanessa; Hametner, Simon; Hernández-Torres, Enedino; Kames, Christian; Endmayr, Verena; Kasprian, Gregor; Höftberger, Romana; Li, David K B; Traboulsee, Anthony; Rauscher, Alexander

    2017-08-01

    Susceptibility-sensitive magnetic resonance imaging (MRI) has gained importance in multiple sclerosis (MS) research because of its versatility, high resolution and excellent sensitivity to changes in tissue structure and composition. In particular, mapping of the resonance frequency of the MR signal and quantitative susceptibility mapping (QSM) have been explored for the description of MS lesions. Many current studies utilizing these techniques attribute increases in the MR frequency or QSM to elevated tissue iron content, in addition to myelin loss. However, this common interpretation is inconsistent with recent histopathological studies. Here, we investigate the nature of MR frequency shifts related to MS lesions by comparing post-mortem MRI data with histology, and contrast them with numerical simulations of the MR signal. We demonstrate that iron accumulation is not the driving source of the MR frequency or QSM image contrast in our sample; rather, most chronic MS lesions are characterized by advanced loss of both myelin and iron. Moreover, our results suggest that the appearance of MS lesions on MR frequency maps and QSM depends on changes in the non-lesional white matter surrounding the lesions. Understanding and accounting for these changes is essential for the quantitative interpretation of MR frequency or QSM data in white matter. Copyright © 2017 John Wiley & Sons, Ltd.

  10. Up-Regulation of Soluble Axl and Mer Receptor Tyrosine Kinases Negatively Correlates with Gas6 in Established Multiple Sclerosis Lesions

    PubMed Central

    Weinger, Jason G.; Omari, Kakuri M.; Marsden, Kurt; Raine, Cedric S.; Shafit-Zagardo, Bridget

    2009-01-01

    Multiple sclerosis is a disease that is characterized by inflammation, demyelination, and axonal damage; it ultimately forms gliotic scars and lesions that severely compromise the function of the central nervous system. Evidence has shown previously that altered growth factor receptor signaling contributes to lesion formation, impedes recovery, and plays a role in disease progression. Growth arrest-specific protein 6 (Gas6), the ligand for the TAM receptor tyrosine kinase family, consisting of Tyro3, Axl, and Mer, is important for cell growth, survival, and clearance of debris. In this study, we show that levels of membrane-bound Mer (205 kd), soluble Mer (∼150 kd), and soluble Axl (80 kd) were all significantly elevated in homogenates from established multiple sclerosis lesions comprised of both chronic active and chronic silent lesions. Whereas in normal tissue Gas6 positively correlated with soluble Axl and Mer, there was a negative correlation between Gas6 and soluble Axl and Mer in established multiple sclerosis lesions. In addition, increased levels of soluble Axl and Mer were associated with increased levels of mature ADAM17, mature ADAM10, and Furin, proteins that are associated with Axl and Mer solubilization. Soluble Axl and Mer are both known to act as decoy receptors and block Gas6 binding to membrane-bound receptors. These data suggest that in multiple sclerosis lesions, dysregulation of protective Gas6 receptor signaling may prolong lesion activity. PMID:19541935

  11. Optical mammography combined with fluorescence imaging: lesion detection using scatterplots

    PubMed Central

    Leproux, Anaïs; van der Voort, Marjolein; van der Mark, Martin B.; Harbers, Rik; van de Ven, Stephanie M. W. Y.; van Leeuwen, Ton G.

    2011-01-01

    Using scatterplots of 2 or 3 parameters, diffuse optical tomography and fluorescence imaging are combined to improve detectability of breast lesions. Small or low contrast phantom-lesions that were missed in the optical and fluorescence images were detected in the scatterplots. In patient measurements, all tumors were visible and easily differentiated from artifacts and areolas in the scatterplots. The different rate of intake and wash out of the fluorescent contrast agent in the healthy versus malignant tissues was also observed in the scatterplot: this information can be used to discriminate malignant lesion from normal structures. PMID:21483622

  12. Automatic detection of red lesions in digital color fundus photographs.

    PubMed

    Niemeijer, Meindert; van Ginneken, Bram; Staal, Joes; Suttorp-Schulten, Maria S A; Abràmoff, Michael D

    2005-05-01

    The robust detection of red lesions in digital color fundus photographs is a critical step in the development of automated screening systems for diabetic retinopathy. In this paper, a novel red lesion detection method is presented based on a hybrid approach, combining prior works by Spencer et al. (1996) and Frame et al. (1998) with two important new contributions. The first contribution is a new red lesion candidate detection system based on pixel classification. Using this technique, vasculature and red lesions are separated from the background of the image. After removal of the connected vasculature the remaining objects are considered possible red lesions. Second, an extensive number of new features are added to those proposed by Spencer-Frame. The detected candidate objects are classified using all features and a k-nearest neighbor classifier. An extensive evaluation was performed on a test set composed of images representative of those normally found in a screening set. When determining whether an image contains red lesions the system achieves a sensitivity of 100% at a specificity of 87%. The method is compared with several different automatic systems and is shown to outperform them all. Performance is close to that of a human expert examining the images for the presence of red lesions.

  13. Novel fMRI working memory paradigm accurately detects cognitive impairment in multiple sclerosis.

    PubMed

    Nelson, Flavia; Akhtar, Mohammad A; Zúñiga, Edward; Perez, Carlos A; Hasan, Khader M; Wilken, Jeffrey; Wolinsky, Jerry S; Narayana, Ponnada A; Steinberg, Joel L

    2017-05-01

    Cognitive impairment (CI) cannot be diagnosed by magnetic resonance imaging (MRI). Functional magnetic resonance imaging (fMRI) paradigms, such as the immediate/delayed memory task (I/DMT), detect varying degrees of working memory (WM). Preliminary findings using I/DMT showed differences in blood oxygenation level dependent (BOLD) activation between impaired (MSCI, n = 12) and non-impaired (MSNI, n = 9) multiple sclerosis (MS) patients. The aim of the study was to confirm CI detection based on I/DMT BOLD activation in a larger cohort of MS patients. The role of T2 lesion volume (LV) and Expanded Disability Status Scale (EDSS) in magnitude of BOLD signal was also sought. A total of 50 patients (EDSS mean ( m) = 3.2, disease duration (DD) m = 12 years, and age m = 40 years) underwent the Minimal Assessment of Cognitive Function in Multiple Sclerosis (MACFIMS) and I/DMT. Working memory activation (WMa) represents BOLD signal during DMT minus signal during IMT. CI was based on MACFIMS. A total of 10 MSNI, 30 MSCI, and 4 borderline patients were included in the analyses. Analysis of variance (ANOVA) showed MSNI had significantly greater WMa than MSCI, in the left prefrontal cortex and left supplementary motor area ( p = 0.032). Regression analysis showed significant inverse correlations between WMa and T2 LV/EDSS in similar areas ( p = 0.005, 0.004, respectively). I/DMT-based BOLD activation detects CI in MS. Larger studies are needed to confirm these findings.

  14. Association of osteolytic lesions, bone mineral loss and trabecular sclerosis with prevalent vertebral fractures in patients with multiple myeloma.

    PubMed

    Borggrefe, J; Giravent, S; Campbell, G; Thomsen, F; Chang, D; Franke, M; Günther, A; Heller, M; Wulff, A

    2015-11-01

    In patients with multiple myeloma (MM), computed tomography is widely used for staging and to detect fractures. Detecting patients at severe fracture risk is of utmost importance. However the criteria for impaired stability of vertebral bodies are not yet clearly defined. We investigated the performance of parameters that can be detected by the radiologist for discrimination of patients with and without fractures. We analyzed 128 whole body low-dose CT of MM patients. In all scans a QCT calibration phantom was integrated into the positioning mat (Image Analysis Phantom(®)). A QCT-software (Structural Insight) performed the volumetric bone mineral density (vBMD) measurements. Description of fracture risk was provided from the clinical radiological report. Suspected progressive disease (PD) was reported by the referring clinicians. Two radiologists that were blinded to study outcome reported on the following parameters based on predefined criteria: reduced radiodensity in the massa lateralis of the os sacrum (RDS), trabecular thickening and sclerosis of three or more vertebrae (TTS), extraosseous MM manifestations (EOM), visible small osteolytic lesions up to a length of 8mm (SO) and osteolytic lesions larger than 8mm (LO). Prevalent vertebral fractures (PVF) were defined by Genant criteria. Age-adjusted standardized odds ratios (sOR) per standard deviation change were derived from logistic regression analysis and area under the curve (AUC) from receiver operating characteristics (ROC) analyses were calculated. ROC curves were compared using the DeLong method. 45% of the 128 patients showed PVF (29 of 75 men, 24 of 53 women). Patients with PVF were not significantly older than patients without fractures (64.6 ± 9.2 vs. 63.3 ± 12.3 years: mean ± SD, p=0.5). The prevalence of each parameter did not differ significantly by sex. Significant fracture discrimination for age adjusted single models was provided by the parameters vBMD (OR 3.5 [1.4-8.8], AUC=0.64 ± 0

  15. Correlation between white matter damage and gray matter lesions in multiple sclerosis patients

    PubMed Central

    Han, Xue-mei; Tian, Hong-ji; Han, Zheng; Zhang, Ce; Liu, Ying; Gu, Jie-bing; Bakshi, Rohit; Cao, Xia

    2017-01-01

    We observed the characteristics of white matter fibers and gray matter in multiple sclerosis patients, to identify changes in diffusion tensor imaging fractional anisotropy values following white matter fiber injury. We analyzed the correlation between fractional anisotropy values and changes in whole-brain gray matter volume. The participants included 20 patients with relapsing-remitting multiple sclerosis and 20 healthy volunteers as controls. All subjects underwent head magnetic resonance imaging and diffusion tensor imaging. Our results revealed that fractional anisotropy values decreased and gray matter volumes were reduced in the genu and splenium of corpus callosum, left anterior thalamic radiation, hippocampus, uncinate fasciculus, right corticospinal tract, bilateral cingulate gyri, and inferior longitudinal fasciculus in multiple sclerosis patients. Gray matter volumes were significantly different between the two groups in the right frontal lobe (superior frontal, middle frontal, precentral, and orbital gyri), right parietal lobe (postcentral and inferior parietal gyri), right temporal lobe (caudate nucleus), right occipital lobe (middle occipital gyrus), right insula, right parahippocampal gyrus, and left cingulate gyrus. The voxel sizes of atrophic gray matter positively correlated with fractional anisotropy values in white matter association fibers in the patient group. These findings suggest that white matter fiber bundles are extensively injured in multiple sclerosis patients. The main areas of gray matter atrophy in multiple sclerosis are the frontal lobe, parietal lobe, caudate nucleus, parahippocampal gyrus, and cingulate gyrus. Gray matter atrophy is strongly associated with white matter injury in multiple sclerosis patients, particularly with injury to association fibers. PMID:28616036

  16. Correlation between white matter damage and gray matter lesions in multiple sclerosis patients.

    PubMed

    Han, Xue-Mei; Tian, Hong-Ji; Han, Zheng; Zhang, Ce; Liu, Ying; Gu, Jie-Bing; Bakshi, Rohit; Cao, Xia

    2017-05-01

    We observed the characteristics of white matter fibers and gray matter in multiple sclerosis patients, to identify changes in diffusion tensor imaging fractional anisotropy values following white matter fiber injury. We analyzed the correlation between fractional anisotropy values and changes in whole-brain gray matter volume. The participants included 20 patients with relapsing-remitting multiple sclerosis and 20 healthy volunteers as controls. All subjects underwent head magnetic resonance imaging and diffusion tensor imaging. Our results revealed that fractional anisotropy values decreased and gray matter volumes were reduced in the genu and splenium of corpus callosum, left anterior thalamic radiation, hippocampus, uncinate fasciculus, right corticospinal tract, bilateral cingulate gyri, and inferior longitudinal fasciculus in multiple sclerosis patients. Gray matter volumes were significantly different between the two groups in the right frontal lobe (superior frontal, middle frontal, precentral, and orbital gyri), right parietal lobe (postcentral and inferior parietal gyri), right temporal lobe (caudate nucleus), right occipital lobe (middle occipital gyrus), right insula, right parahippocampal gyrus, and left cingulate gyrus. The voxel sizes of atrophic gray matter positively correlated with fractional anisotropy values in white matter association fibers in the patient group. These findings suggest that white matter fiber bundles are extensively injured in multiple sclerosis patients. The main areas of gray matter atrophy in multiple sclerosis are the frontal lobe, parietal lobe, caudate nucleus, parahippocampal gyrus, and cingulate gyrus. Gray matter atrophy is strongly associated with white matter injury in multiple sclerosis patients, particularly with injury to association fibers.

  17. Lesion detection and quantitation of positron emission mammography

    SciTech Connect

    Qi, Jinyi; Huesman, Ronald H.

    2001-12-01

    A Positron Emission Mammography (PEM) scanner dedicated to breast imaging is being developed at our laboratory. We have developed a list mode likelihood reconstruction algorithm for this scanner. Here we theoretically study the lesion detection and quantitation. The lesion detectability is studied theoretically using computer observers. We found that for the zero-order quadratic prior, the region of interest observer can achieve the performance of the prewhitening observer with a properly selected smoothing parameter. We also study the lesion quantitation using the test statistic of the region of interest observer. The theoretical expressions for the bias, variance, and ensemble mean squared error of the quantitation are derived. Computer simulations show that the theoretical predictions are in good agreement with the Monte Carlo results for both lesion detection and quantitation.

  18. 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

  19. 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

  20. 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

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

    PubMed

    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; Bakshi, Rohit

    2016-01-01

    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. 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. 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). 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. © 2015 The Authors. Journal of Neuroimaging published by Wiley Periodicals, Inc. on behalf of American Society of Neuroimaging.

  2. 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

  3. Small heat shock proteins are induced during multiple sclerosis lesion development in white but not grey matter.

    PubMed

    Peferoen, Laura A N; Gerritsen, Wouter H; Breur, Marjolein; Ummenthum, Kimberley M D; Peferoen-Baert, Regina M B; van der Valk, Paul; van Noort, Johannes M; Amor, Sandra

    2015-12-22

    The important protective role of small heat-shock proteins (HSPs) in regulating cellular survival and migration, counteracting protein aggregation, preventing apoptosis, and regulating inflammation in the central nervous system is now well-recognized. Yet, their role in the neuroinflammatory disorder multiple sclerosis (MS) is largely undocumented. With the exception of alpha B-crystallin (HSPB5), little is known about the roles of small HSPs in disease. Here, we examined the expression of four small HSPs during lesion development in MS, focussing on their cellular distribution, and regional differences between white matter (WM) and grey matter (GM). It is well known that MS lesions in these areas differ markedly in their pathology, with substantially more intense blood-brain barrier damage, leukocyte infiltration and microglial activation typifying WM but not GM lesions. We analysed transcript levels and protein distribution profiles for HSPB1, HSPB6, HSPB8 and HSPB11 in MS lesions at different stages, comparing them with normal-appearing brain tissue from MS patients and non-neurological controls. During active stages of demyelination in WM, and especially the centre of chronic active MS lesions, we found significantly increased expression of HSPB1, HSPB6 and HSPB8, but not HSPB11. When induced, small HSPs were exclusively found in astrocytes but not in oligodendrocytes, microglia or neurons. Surprisingly, while the numbers of astrocytes displaying high expression of small HSPs were markedly increased in actively demyelinating lesions in WM, no such induction was observed in GM lesions. This difference was particularly obvious in leukocortical lesions covering both WM and GM areas. Since induction of small HSPs in astrocytes is apparently a secondary response to damage, their differential expression between WM and GM likely reflects differences in mediators that accompany demyelination in either WM or GM during MS. Our findings also suggest that during MS

  4. Association of Parkinson disease-related protein PINK1 with Alzheimer disease and multiple sclerosis brain lesions.

    PubMed

    Wilhelmus, Micha M M; van der Pol, Susanne M A; Jansen, Quentin; Witte, Maarten E; van der Valk, Paul; Rozemuller, Annemieke J M; Drukarch, Benjamin; de Vries, Helga E; Van Horssen, Jack

    2011-02-01

    Mitochondrial dysfunction and oxidative stress are hallmarks of various neurological disorders, including multiple sclerosis (MS), Alzheimer disease (AD), and Parkinson disease (PD). Mutations in PINK1, a mitochondrial kinase, have been linked to the occurrence of early onset parkinsonism. Currently, various studies support the notion of a neuroprotective role for PINK1, as it protects cells from stress-mediated mitochondrial dysfunction, oxidative stress, and apoptosis. Because information about the distribution pattern of PINK1 in neurological diseases other than PD is scarce, we here investigated PINK1 expression in well-characterized brain samples derived from MS and AD individuals using immunohistochemistry. In control gray matter PINK1 immunoreactivity was observed in neurons, particularly neurons in layers IV-VI. Astrocytes were the most prominent cell type decorated by anti-PINK1 antibody in the white matter. In addition, PINK1 staining was observed in the cerebrovasculature. In AD, PINK1 was found to colocalize with classic senile plaques and vascular amyloid depositions, as well as reactive astrocytes associated with the characteristic AD lesions. Interestingly, PINK1 was absent from neurofibrillary tangles. In active demyelinating MS lesions we observed a marked astrocytic PINK1 immunostaining, whereas astrocytes in chronic lesions were weakly stained. Taken together, we observed PINK1 immunostaining in both AD and MS lesions, predominantly in reactive astrocytes associated with these lesions, suggesting that the increase in astrocytic PINK1 protein might be an intrinsic protective mechanism to limit cellular injury. Copyright © 2010 Elsevier Inc. All rights reserved.

  5. The effects of everolimus on tuberous sclerosis-associated lesions can be dramatic but may be impermanent.

    PubMed

    Miller, Joseph M; Wachsman, Ashley; Haker, Katherine; Majlessipour, Fataneh; Danielpour, Moise; Puliyanda, Dechu

    2015-01-01

    Tuberous sclerosis complex (TSC) predisposes to the development of benign lesions within multiple organ systems, including the brain, kidneys, heart, lungs, and skin. Disease mortality is due to space-occupying subependymal giant cell astrocytomas and hemorrhage-prone renal angiomyolipomas. The recent use of mTORC1 inhibitors, such as everolimus, has allowed for direct targeting of TSC-associated mass lesions without apparent effect on surrounding tissues. Because of the mechanism of these drugs, there is reason to believe that these effects are not durable and that there may be need for continued long-term maintenance therapy. We present a case of TSC-associated mass lesions that were ill-suited for definitive surgical therapy. The patient was started on everolimus, however due to a complex social situation treatment was discontinued and ultimately resumed many months later. Radiologic studies acquired before and after each period of therapeutic onset/cessation reveal the dramatic but impermanent effects of mTORC1 inhibition. While everolimus provides a non-invasive way to treat TSC-associated lesions, patients may require lifelong therapy. When termination of therapy is considered, the patient should be made aware of the expectation of potentially dramatic increases in lesion size. If consideration is to be given to definitive surgical therapy, it should be pursued while the patient is still on the medication, or at least soon after treatment is halted.

  6. 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.

  7. 7 Tesla Magnetic Resonance Imaging to Detect Cortical Pathology in Multiple Sclerosis

    PubMed Central

    van Gelderen, Peter; Merkle, Hellmuth; Chen, Christina; Lassmann, Hans; Duyn, Jeff H.; Bagnato, Francesca

    2014-01-01

    Background Neocortical lesions (NLs) are an important pathological component of multiple sclerosis (MS), but their visualization by magnetic resonance imaging (MRI) remains challenging. Objectives We aimed at assessing the sensitivity of multi echo gradient echo (ME-GRE) T2*-weighted MRI at 7.0 Tesla in depicting NLs compared to myelin and iron staining. Methods Samples from two MS patients were imaged post mortem using a whole body 7T MRI scanner with a 24-channel receive-only array. Isotropic 200 micron resolution images with varying T2* weighting were reconstructed from the ME-GRE data and converted into R2* maps. Immunohistochemical staining for myelin (proteolipid protein, PLP) and diaminobenzidine-enhanced Turnbull blue staining for iron were performed. Results Prospective and retrospective sensitivities of MRI for the detection of NLs were 48% and 67% respectively. We observed MRI maps detecting only a small portion of 20 subpial NLs extending over large cortical areas on PLP stainings. No MRI signal changes suggestive of iron accumulation in NLs were observed. Conversely, R2* maps indicated iron loss in NLs, which was confirmed by histological quantification. Conclusions High-resolution post mortem imaging using R2* and magnitude maps permits detection of focal NLs. However, disclosing extensive subpial demyelination with MRI remains challenging. PMID:25303286

  8. Latency of multifocal visual evoked potentials in nonoptic neuritis eyes of multiple sclerosis patients associated with optic radiation lesions.

    PubMed

    Alshowaeir, Daniah; Yiannikas, Con; Garrick, Raymond; Parratt, John; Barnett, Michael H; Graham, Stuart L; Klistorner, Alexander

    2014-05-15

    The aim of the study was to test the hypothesis that latency delay of multifocal visual evoked potentials (mfVEP) in nonoptic neuritis (NON) eyes of multiple sclerosis (MS) patients is related to retrochiasmal demyelinating lesions. A total of 57 MS patients with no history of optic neuritis at least in one eye, and 25 age- and sex-matched healthy controls was enrolled. Probabilistic tractography was used to reconstruct optic radiation (OR) fibers. The MS lesion volume within and outside of OR was calculated. Diffusion tensor imaging (DTI) indices were measured along OR fibers. The relationship of the mfVEP latency with OR lesions and DTI indices was examined. Average mfVEP latency in the MS cohort was significantly delayed compared to controls (P < 0.0001). Of the patients, 77% demonstrated OR lesions. Axial, radial, and mean diffusivity were significantly abnormal in MS patients (P < 0.001). Partial correlation demonstrated significant association between mfVEP latency delay and OR lesion load. There was also significant correlation between MfVEP latency and OR DTI. Subgroup analysis revealed significantly higher correlations in patients without a history of ON in either eye compared to the fellow eye of patients with previous ON. The findings of this study support our hypothesis that latency delay of the mfVEP in eyes of MS patients without previous ON is related to retrogenicular demyelinating lesions. Additionally, this study demonstrated that a previous episode of ON in the fellow eye may be a significant confounding factor, masking the relationship between the latency and OR lesions. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  9. Do positive or negative stressful events predict the development of new brain lesions in people with Multiple Sclerosis?

    PubMed Central

    Burns, Michelle Nicole; Nawacki, Ewa; Kwasny, Mary J.; Pelletier, Daniel; Mohr, David C.

    2014-01-01

    Background Stressful life events have long been suspected to contribute to multiple sclerosis (MS) disease activity. The few studies examining the relationship between stressful events and neuroimaging markers have been small and inconsistent. This study examined whether different types of stressful events and perceived stress could predict development of brain lesions. Methods This was a secondary analysis of 121 patients with MS followed for 48 weeks during a randomized controlled trial comparing Stress Management Therapy for MS to a waitlist control. Patients underwent MRI’s every 8 weeks. Monthly, patients completed an interview measure assessing stressful life events, and self-report measures of perceived stress, anxiety, and depressive symptoms, which were used to predict the presence of gadolinium enhancing (Gd+) and T2 lesions on MRI’s 29–62 days later. Participants classified stressful events as positive or negative. Negative events were considered “major” if they involved physical threat or threat to the patient’s family structure, and “moderate” otherwise. Results Positive stressful events predicted decreased risk for subsequent Gd+ lesions in the control group (OR=.53 for each additional positive stressful event, 95% CI=.30–.91) and less risk for new or enlarging T2 lesions regardless of group assignment (OR=.74, 95% CI=.55–.99). Across groups, major negative stressful events predicted Gd+ lesions (OR=1.77, 95% CI=1.18–2.64) and new or enlarging T2 lesions (OR=1.57, 95% CI=1.11–2.23), while moderate negative stressful events, perceived stress, anxiety, and depressive symptoms did not. Conclusions Major negative stressful events predict increased risk for Gd+ and T2 lesions, while positive stressful events predict decreased risk. PMID:23680407

  10. 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.

  11. 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

  12. 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

  13. Impact of JPEG 2000 compression on lesion detection in MR imaging.

    PubMed

    Paz, Juan; Pérez, Marlen; Schelkens, Peter; Rodríguez, José

    2009-11-01

    Lossy compression algorithms enable the efficient transmission of large medical image datasets over bandwidth-limited digital networks or facilitate the long-term storage of the daily image production. Although JPEG 2000 has been adopted by DICOM as the standard for lossy-to-lossless compression, still a set of guidelines needs to be derived that allows for the usage of the lossy mode, potentially jeopardizing the accuracy of lesion detection and characterization, and so, of the resulting diagnosis task effectiveness in the medical diagnosis process. In this article the authors present and evaluate a generic methodology for the determination of the minimal bit rate that still ensures an accurate detection in magnetic resonance images of specific lesions. In this article, they demonstrate the methodology for two particular pathologies, i.e., multiple sclerosis and Virchow-Robin space enlargements. Involving qualified personnel, the minimal bit rate is estimated from ROC experiments initially simulated through mathematical observers that are designed with several objective metrics. The mathematical observer models included three variants of the Hotelling observer plus the non-prewhitening matched filter with eye model, while the objective measures are based on distance, correlation, singular value decomposition, and structural similarity. The results indicate that the highest compression without seriously affecting the detection of the studied lesions is achieved at a bit rate of 0.125 bpp. At this value, the detection effectiveness exceeded 95% with less than 5% standard deviation, while only 4.4% of the outcomes were classified as false negatives by the experts and 11.6% as false positives. The optimal bit rate found assures that important information on the small investigated structures is still preserved for their accurate detection and their a posteriori characterization.

  14. Clinical evaluation of an all-in-one adhesive in non-carious cervical lesions with different degrees of dentin sclerosis.

    PubMed

    Ritter, André V; Heymann, Harald O; Swift, Edward J; Sturdevant, John R; Wilder, Aldridge D

    2008-01-01

    This randomized clinical trial compared the performance of an all-in-one adhesive (iBond) applied in sclerotic and non-sclerotic non-carious cervical lesions with that of a three-step etch-prime-bond adhesive (Gluma Solid Bond, SB). One-hundred and five lesions were randomly assigned to four groups according to adhesive, sclerosis scale and technique: 1) SB applied to lesions with sclerosis scale 1 and 2 (n=26); 2) iBond applied to lesions with sclerosis scale 1 and 2 (n=28); 3) iBond applied to lesions with sclerosis scale 3 and 4 (n=25) and 4) iBond applied with prior acid-etching to lesions with sclerosis scale 3 and 4 (n=26). A microfilled composite (Durafill VS) was used as the restorative material. The restorations were evaluated for retention, color match, marginal adaptation, anatomic form, cavosurface margin discoloration, secondary caries, pre- and post-operative sensitivity, surface texture and fracture at insertion (baseline), 6, 18 months and at 3 years using modified USPHS evaluation criteria (Alfa=excellent; Bravo=clinically acceptable; Charlie=clinically unacceptable). There was a high percentage of Bravo scores for marginal adaptation (4%-32%) and marginal discoloration (18%-60%) in Groups 2, 3 and 4, but all groups had <5% Charlie scores at 6 months and <10% Charlie scores at 18 months for retention and marginal discoloration, respectively. However, it should be noted that 13% of the restorations in Group 4 were not retained at three years.

  15. Gray Matter Atrophy Is Primarily Related to Demyelination of Lesions in Multiple Sclerosis: A Diffusion Tensor Imaging MRI Study

    PubMed Central

    Tóth, Eszter; Szabó, Nikoletta; Csete, Gergõ; Király, András; Faragó, Péter; Spisák, Tamás; Bencsik, Krisztina; Vécsei, László; Kincses, Zsigmond T.

    2017-01-01

    Objective: Cortical pathology, periventricular demyelination, and lesion formation in multiple sclerosis (MS) are related (Hypothesis 1). Factors in the cerebrospinal fluid close to these compartments could possibly drive the parallel processes. Alternatively, the cortical atrophy could be caused by remote axonal transection (Hypothesis 2). Since MRI can differentiate between demyelination and axon loss, we used this imaging modality to investigate the correlation between the pattern of diffusion parameter changes in the periventricular- and deep white matter and the gray matter atrophy. Methods: High-resolution T1-weighted, FLAIR, and diffusion MRI images were acquired in 52 RRMS patients and 50 healthy, age-matched controls. We used EDSS to estimate the clinical disability. We used Tract Based Spatial Statistics to compare diffusion parameters (fractional anisotropy, mean, axial, and radial diffusivity) between groups. We evaluated global brain, white, and gray matter atrophy with SIENAX. Averaged, standard diffusion parameters were calculated in four compartment: periventricular lesioned and normal appearing white matter, non-periventricular lesioned and normal appearing white matter. PLS regression was used to identify which diffusion parameter and in which compartment best predicts the brain atrophy and clinical disability. Results: In our diffusion tensor imaging study compared to controls we found extensive alterations of fractional anisotropy, mean and radial diffusivity and smaller changes of axial diffusivity (maximal p > 0.0002) in patients that suggested demyelination in the lesioned and in the normal appearing white matter. We found significant reduction in total brain, total white, and gray matter (patients: 718.764 ± 14.968, 323.237 ± 7.246, 395.527 ± 8.050 cm3, controls: 791.772 ± 22.692, 355.350 ± 10.929, 436.422 ± 12.011 cm3; mean ± SE), (p < 0.015; p < 0.0001; p < 0.009; respectively) of patients compared to controls. The PLS analysis

  16. Gray Matter Atrophy Is Primarily Related to Demyelination of Lesions in Multiple Sclerosis: A Diffusion Tensor Imaging MRI Study.

    PubMed

    Tóth, Eszter; Szabó, Nikoletta; Csete, Gergõ; Király, András; Faragó, Péter; Spisák, Tamás; Bencsik, Krisztina; Vécsei, László; Kincses, Zsigmond T

    2017-01-01

    Objective: Cortical pathology, periventricular demyelination, and lesion formation in multiple sclerosis (MS) are related (Hypothesis 1). Factors in the cerebrospinal fluid close to these compartments could possibly drive the parallel processes. Alternatively, the cortical atrophy could be caused by remote axonal transection (Hypothesis 2). Since MRI can differentiate between demyelination and axon loss, we used this imaging modality to investigate the correlation between the pattern of diffusion parameter changes in the periventricular- and deep white matter and the gray matter atrophy. Methods: High-resolution T1-weighted, FLAIR, and diffusion MRI images were acquired in 52 RRMS patients and 50 healthy, age-matched controls. We used EDSS to estimate the clinical disability. We used Tract Based Spatial Statistics to compare diffusion parameters (fractional anisotropy, mean, axial, and radial diffusivity) between groups. We evaluated global brain, white, and gray matter atrophy with SIENAX. Averaged, standard diffusion parameters were calculated in four compartment: periventricular lesioned and normal appearing white matter, non-periventricular lesioned and normal appearing white matter. PLS regression was used to identify which diffusion parameter and in which compartment best predicts the brain atrophy and clinical disability. Results: In our diffusion tensor imaging study compared to controls we found extensive alterations of fractional anisotropy, mean and radial diffusivity and smaller changes of axial diffusivity (maximal p > 0.0002) in patients that suggested demyelination in the lesioned and in the normal appearing white matter. We found significant reduction in total brain, total white, and gray matter (patients: 718.764 ± 14.968, 323.237 ± 7.246, 395.527 ± 8.050 cm(3), controls: 791.772 ± 22.692, 355.350 ± 10.929, 436.422 ± 12.011 cm(3); mean ± SE), (p < 0.015; p < 0.0001; p < 0.009; respectively) of patients compared to controls. The PLS analysis

  17. 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.

  18. Echoplanar MR imaging for ultrafast detection of brain lesions.

    PubMed

    Patel, M R; Siewert, B; Klufas, R; Yousuf, N; Edelman, R R; Warach, S

    1999-08-01

    We retrospectively evaluated the use of echo-planar imaging for ultrafast detection of brain lesions. In our retrospective study, 61 patients were imaged with the following echo-planar sequences: single-shot proton density-weighted, single-shot T2-weighted, single-shot T2-weighted high-resolution, multishot proton density-weighted, and multishot T2-weighted. Lesions revealed in these patients ranged from 0.5 to 12.0 cm (mean, 3.7 cm) and were the result of tumor (n = 16), stroke (n = 21), demyelination (n = 18), and toxoplasmosis (n = 2). Four patients had scans with normal findings. Two neuroradiologists who were unaware of pertinent clinical data reviewed the images. The images were retrospectively compared with conventional spin-echo images for diagnosis, sensitivity of lesion detection, and qualitative criteria: subjective image quality, gray and white matter differentiation, lesion conspicuity, delineation of lesion borders, and artifacts. (Artifacts included those caused by motion, susceptibility, pulsation, and ghosting.) Quantitative criteria, including signal-to-noise and signal difference-to-noise measurements, were also evaluated in 40 lesions. Sensitivity for lesion detection was 97% for single-shot echo-planar T2-weighted MR images and 100% for multishot echo-planar T2-weighted MR images. Single-shot echo-planar proton density-weighted MR images had the highest signal-to-noise ratio (91.2+/-19.3). Echo-planar T2-weighted MR images had the highest signal difference-to-noise (33.8+/-22.9). Echo-planar sequences were superior to spin-echo sequences regarding motion and pulsation artifacts. Spin-echo sequences lacked susceptibility and ghosting artifacts, and were superior in lesion conspicuity and delineation of lesion borders. In this study, echo-planar sequences were as sensitive as conventional spin-echo imaging for the diagnostic assessment of lesions. Echo-planar sequences had a strikingly shorter acquisition time and substantially reduced motion and

  19. Detection of infarct lesions from single MRI modality using inconsistency between voxel intensity and spatial location--a 3-D automatic approach.

    PubMed

    Shen, Shan; Szameitat, André J; Sterr, Annette

    2008-07-01

    Detection of infarct lesions using traditional segmentation methods is always problematic due to intensity similarity between lesions and normal tissues, so that multispectral MRI modalities were often employed for this purpose. However, the high costs of MRI scan and the severity of patient conditions restrict the collection of multiple images. Therefore, in this paper, a new 3-D automatic lesion detection approach was proposed, which required only a single type of anatomical MRI scan. It was developed on a theory that, when lesions were present, the voxel-intensity-based segmentation and the spatial-location-based tissue distribution should be inconsistent in the regions of lesions. The degree of this inconsistency was calculated, which indicated the likelihood of tissue abnormality. Lesions were identified when the inconsistency exceeded a defined threshold. In this approach, the intensity-based segmentation was implemented by the conventional fuzzy c-mean (FCM) algorithm, while the spatial location of tissues was provided by prior tissue probability maps. The use of simulated MRI lesions allowed us to quantitatively evaluate the performance of the proposed method, as the size and location of lesions were prespecified. The results showed that our method effectively detected lesions with 40-80% signal reduction compared to normal tissues (similarity index > 0.7). The capability of the proposed method in practice was also demonstrated on real infarct lesions from 15 stroke patients, where the lesions detected were in broad agreement with true lesions. Furthermore, a comparison to a statistical segmentation approach presented in the literature suggested that our 3-D lesion detection approach was more reliable. Future work will focus on adapting the current method to multiple sclerosis lesion detection.

  20. Neural Network-Based Learning Kernel for Automatic Segmentation of Multiple Sclerosis Lesions on Magnetic Resonance Images

    PubMed Central

    Khastavaneh, H.; Ebrahimpour-Komleh, H.

    2017-01-01

    Background: Multiple Sclerosis (MS) is a degenerative disease of central nervous system. MS patients have some dead tissues in their brains called MS lesions. MRI is an imaging technique sensitive to soft tissues such as brain that shows MS lesions as hyper-intense or hypo-intense signals. Since manual segmentation of these lesions is a laborious and time consuming task, automatic segmentation is a need. Materials and Methods: In order to segment MS lesions, a method based on learning kernels has been proposed. The proposed method has three main steps namely; pre-processing, sub-region extraction and segmentation. The segmentation is performed by a kernel. This kernel is trained using a modified version of a special type of Artificial Neural Networks (ANN) called Massive Training ANN (MTANN). The kernel incorporates surrounding pixel information as features for classification of middle pixel of kernel. The materials of this study include a part of MICCAI 2008 MS lesion segmentation grand challenge data-set. Results: Both qualitative and quantitative results show promising results. Similarity index of 70 percent in some cases is considered convincing. These results are obtained from information of only one MRI channel rather than multi-channel MRIs. Conclusion: This study shows the potential of surrounding pixel information to be incorporated in segmentation by learning kernels. The performance of proposed method will be improved using a special pre-processing pipeline and also a post-processing step for reducing false positives/negatives. An important advantage of proposed model is that it uses just FLAIR MRI that reduces computational time and brings comfort to patients. PMID:28580337

  1. [Differences in the spectroscopy of the lesions of the remitting relapsing form of multiple sclerosis shown by magnetic resonance].

    PubMed

    Martínez-Bisbal, M C; Celda, B; Martí-Bonmat, L; Casanova-Estruch, B; Coret-Ferrer, F

    Multiple sclerosis (MS) is a chronic demyelinating disorder of the central nervous system, characterized by the presence of inflammatory lesions. To analyze the biochemical profile of the demyelinating lesions of the initial forms of MS (remitting relapsing) by analyzing the proton magnetic resonance spectra (1H MRS) to characterize the process of demyelination and relate it to the metabolites and clinical variables analyzed. We analyzed the largest demyelinating lesions in eight patients with remitting relapsing MS (RRMS) using the technique of single volume 1H MRS (VOI) with short echo time. The spectra of the white matter of two healthy control were used as reference. NAA/Cr and NAA/Cho value ratios decrease and mI/Cr one increase in all spectra lesions as compared to healthy controls. In four of the eight patients, the Cho/Cr was higher than in the controls. Qualitative and quantitative differences in the resonances of macromolecules were observed, related to the biochemistry of the process of demyelination. These differences in NAA/Cr, Cho/Cr, mI/Cr and macromolecules probably represent different stages in the evolution of the plaques. MRS is a non invasive technique able to observe biochemical variations related to the evolution process of demyelination. Activity of the lesion is shown by the increment of resonances around 0.9 1.3 ppm. An increase in mI seems to occur at an early stage of demyelination and later the NAA is reduced. The initial forms of MS show metabolic alterations in the plaques which are similar to the most advanced forms of MS.

  2. 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.

  3. 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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Using multiple imputation to efficiently correct cerebral MRI whole brain lesion and atrophy data in patients with multiple sclerosis.

    PubMed

    Chua, Alicia S; Egorova, Svetlana; Anderson, Mark C; Polgar-Turcsanyi, Mariann; Chitnis, Tanuja; Weiner, Howard L; Guttmann, Charles R G; Bakshi, Rohit; Healy, Brian C

    2015-10-01

    Automated segmentation of brain MRI scans into tissue classes is commonly used for the assessment of multiple sclerosis (MS). However, manual correction of the resulting brain tissue label maps by an expert reader remains necessary in many cases. Since automated segmentation data awaiting manual correction are "missing", we proposed to use multiple imputation (MI) to fill-in the missing manually-corrected MRI data for measures of normalized whole brain volume (brain parenchymal fraction-BPF) and T2 hyperintense lesion volume (T2LV). Automated and manually corrected MRI measures from 1300 patients enrolled in the Comprehensive Longitudinal Investigation of Multiple Sclerosis at the Brigham and Women's Hospital (CLIMB) were identified. Simulation studies were conducted to assess the performance of MI with missing data both missing completely at random and missing at random. An imputation model including the concurrent automated data as well as clinical and demographic variables explained a high proportion of the variance in the manually corrected BPF (R(2)=0.97) and T2LV (R(2)=0.89), demonstrating the potential to accurately impute the missing data. Further, our results demonstrate that MI allows for the accurate estimation of group differences with little to no bias and with similar precision compared to an analysis with no missing data. We believe that our findings provide important insights for efficient correction of automated MRI measures to obviate the need to perform manual correction on all cases. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Clonal Expansions of Cd8+ T Cells Dominate the T Cell Infiltrate in Active Multiple Sclerosis Lesions as Shown by Micromanipulation and Single Cell Polymerase Chain Reaction

    PubMed Central

    Babbe, Holger; Roers, Axel; Waisman, Ari; Lassmann, Hans; Goebels, Norbert; Hohlfeld, Reinhard; Friese, Michael; Schröder, Roland; Deckert, Martina; Schmidt, Stephan; Ravid, Rivka; Rajewsky, Klaus

    2000-01-01

    Clonal composition and T cell receptor (TCR) repertoire of CD4+ and CD8+ T cells infiltrating actively demyelinating multiple sclerosis (MS) lesions were determined with unprecedented resolution at the level of single cells. Individual CD4+ or CD8+ T cells were isolated from frozen sections of lesional tissue by micromanipulation and subjected to single target amplification of TCR-β gene rearrangements. This strategy allows the assignment of a TCR variable region (V region) sequence to the particular T cell from which it was amplified. Sequence analysis revealed that in both cases investigated, the majority of CD8+ T cells belonged to few clones. One of these clones accounted for 35% of CD8+ T cells in case 1. V region sequence comparison revealed signs of selection for common peptide specificities for some of the CD8+ T cells in case 1. In both cases, the CD4+ T cell population was more heterogeneous. Most CD4+ and CD8+ clones were represented in perivascular infiltrates as well as among parenchymal T cells. In case 2, two of the CD8+ clones identified in brain tissue were also detected in peripheral blood. Investigation of the antigenic specificities of expanded clones may help to elucidate their functional properties. PMID:10934227

  6. Quantitative MRI for Analysis of Active Multiple Sclerosis Lesions without Gadolinium-Based Contrast Agent.

    PubMed

    Blystad, I; Håkansson, I; Tisell, A; Ernerudh, J; Smedby, Ö; Lundberg, P; Larsson, E-M

    2016-01-01

    Contrast-enhancing MS lesions are important markers of active inflammation in the diagnostic work-up of MS and in disease monitoring with MR imaging. Because intravenous contrast agents involve an expense and a potential risk of adverse events, it would be desirable to identify active lesions without using a contrast agent. The purpose of this study was to evaluate whether pre-contrast injection tissue-relaxation rates and proton density of MS lesions, by using a new quantitative MR imaging sequence, can identify active lesions. Forty-four patients with a clinical suspicion of MS were studied. MR imaging with a standard clinical MS protocol and a quantitative MR imaging sequence was performed at inclusion (baseline) and after 1 year. ROIs were placed in MS lesions, classified as nonenhancing or enhancing. Longitudinal and transverse relaxation rates, as well as proton density were obtained from the quantitative MR imaging sequence. Statistical analyses of ROI values were performed by using a mixed linear model, logistic regression, and receiver operating characteristic analysis. Enhancing lesions had a significantly (P < .001) higher mean longitudinal relaxation rate (1.22 ± 0.36 versus 0.89 ± 0.24), a higher mean transverse relaxation rate (9.8 ± 2.6 versus 7.4 ± 1.9), and a lower mean proton density (77 ± 11.2 versus 90 ± 8.4) than nonenhancing lesions. An area under the receiver operating characteristic curve value of 0.832 was obtained. Contrast-enhancing MS lesions often have proton density and relaxation times that differ from those in nonenhancing lesions, with lower proton density and shorter relaxation times in enhancing lesions compared with nonenhancing lesions. © 2016 by American Journal of Neuroradiology.

  7. Lesion detection using Gabor-based saliency field mapping

    NASA Astrophysics Data System (ADS)

    Macenko, Marc; Luo, Rutao; Celenk, Mehmet; Ma, Limin; Zhou, Qiang

    2007-03-01

    In this paper, we present a method that detects lesions in two-dimensional (2D) cross-sectional brain images. By calculating the major and minor axes of the brain, we calculate an estimate of the background, without any a priori information, to use in inverse filtering. Shape saliency computed by a Gabor filter bank is used to further refine the results of the inverse filtering. The proposed algorithm was tested on different images of "The Whole Brain Atlas" database. The experimental results have produced 93% classification accuracy in processing 100 arbitrary images, representing different kinds of brain lesion.

  8. Ultra-high field MTR and qR2* differentiates subpial cortical lesions from normal-appearing gray matter in multiple sclerosis.

    PubMed

    Jonkman, Laura E; Fleysher, Lazar; Steenwijk, Martijn D; Koeleman, Jan A; de Snoo, Teun-Pieter; Barkhof, Frederik; Inglese, Matilde; Geurts, Jeroen Jg

    2016-09-01

    Cortical gray matter (GM) demyelination is frequent and clinically relevant in multiple sclerosis (MS). Quantitative magnetic resonance imaging (qMRI) sequences such as magnetization transfer ratio (MTR) and quantitative R2* (qR2*) can capture pathological subtleties missed by conventional magnetic resonance imaging (MRI) sequences. Although differences in MTR and qR2* have been reported between lesional and non-lesional tissue, differences between lesion types or lesion types and myelin density matched normal-appearing gray matter (NAGM) have not been found or investigated. Identify quantitative differences in histopathologically verified GM lesion types and matched NAGM at ultra-high field strength. Using 7T post-mortem MRI, MRI lesions were marked on T2 images and co-registered to the calculated MTR and qR2* maps for further evaluation. In all, 15 brain slices were collected, containing a total of 74 cortical GM lesions and 45 areas of NAGM. Intracortical lesions had lower MTR and qR2* values compared to NAGM. Type I lesions showed lower MTR than type III lesions. Type III lesions showed lower MTR than matched NAGM, and type I and IV lesions showed lower qR2* than matched NAGM. qMRI at 7T can provide additional information on extent of cortical pathology, especially concerning subpial lesions. This may be relevant for monitoring disease progression and potential treatment effects. © The Author(s), 2015.

  9. Discrepancy in CCL2 and CCR2 expression in white versus grey matter hippocampal lesions of Multiple Sclerosis patients.

    PubMed

    Prins, Marloes; Dutta, Ranjan; Baselmans, Bart; Brevé, John J P; Bol, John G J M; Deckard, Sadie A; van der Valk, Paul; Amor, Sandra; Trapp, Bruce D; de Vries, Helga E; Drukarch, Benjamin; van Dam, Anne-Marie

    2014-08-23

    A remarkable pathological difference between grey matter lesions (GML) and white matter lesions (WML) in Multiple Sclerosis (MS) patients is the paucity of infiltrating leukocytes in GML. To better understand these pathological differences, we hypothesize that the chemokine monocyte chemotactic protein-1 (MCP-1 or CCL2), of importance for leukocyte migration, and its receptor CCR2 are more abundantly expressed in WML than in GML of MS patients. To this end, we analyzed CCL2 and CCR2 expression in the hippocampus, comprising WML and GML,of post-mortem MS patients, and of control subjects. CCL2 and CCR2 mRNA were significantly increased in demyelinated MS hippocampus. Semi-quantification of CCL2 and CCR2 immunoreactivity showed that CCL2 is present in astrocytes only in active WML. CCR2 is upregulated in monocytes/macrophages or amoeboid microglia in active WML, and in ramified microglia in active GML, although to a lesser extent. As a follow-up, we observed a significantly increased CCL2 production by WM-, but not GM-derived astrocytes upon stimulation with bz-ATP in vitro. Finally, upon CCL2 stimulation, GM-derived microglia significantly increased their proliferation rate. We conclude that within hippocampal lesions, CCL2 expression is mainly restricted to WML, whereas the receptor CCR2 is upregulated in both WML and GML. The relative absence of CCL2 in GML may explain the lack of infiltrating immune cells in this type of lesions. We propose that the divergent expression of CCL2 and CCR2 in WML and GML explains or contributes to the differences in WML and GML formation in MS.

  10. In Vivo Imaging of Cortical Inflammation and Subpial Pathology in Multiple Sclerosis by Combined PET and MRI

    DTIC Science & Technology

    2014-09-01

    and Subpial Pathology in Multiple Sclerosis by Combined PET and MRI PRINCIPAL INVESTIGATOR: Dr. Caterina Mainero...studies in multiple sclerosis (MS) suggested that cortical demyelinating lesions, which are hardly detected in vivo on conventional magnetic resonance...disease progression in many MS cases. 15. SUBJECT TERMS Multiple sclerosis ; cortex; cortical sulci; neuroinflammation; microglia; cortical

  11. [Retinal image analysis to detect lesions associated with diabetic retinopathy].

    PubMed

    Sánchez Gutiérrez, C I; López Gálvez, M I; Hornero Sánchez, R; Poza Crespo, J

    2004-12-01

    Diabetic retinopathy is a leading cause of vision loss in developed countries. Regular diabetic retinal eye screenings are needed to detect early signs of retinopathy, so that appropriate treatments can be rendered to prevent blindness. Digital imaging is becoming available as a means of screening for diabetic retinopathy. However, with the large number of patients undergoing screenings, medical professionals require a tremendous amount of time and effort in order to analyse and diagnose the fundus photographs. Our aim is to develop an automatic algorithm using digital image analysis for detecting these early lesions from retinal images. An automatic method to detect hard exudates, a lesion associated with diabetic retinopathy, is proposed. The algorithm is based on their colour, using a statistical classification, and their sharp edges, applying an edge detector, to localise them. A sensitivity of 79.62% with a mean number of 3 false positives per image is obtained in a database of 20 retinal images with variable colour, brightness and quality. It can also be seen that the number of the false negative cases increases when the hard exudates were very close to the vessel tree. The long term goal of the project is to automate the screening for diabetic retinopathy with retinal images. We have described the preliminary development of a tool to provide automatic analysis of digital fundus photographs to localise hard exudates. Future work will address the issue of improving the obtained results and also will focus on detecting other lesions.

  12. Improved operator agreement and efficiency using the minimum area contour change method for delineation of hyperintense multiple sclerosis lesions on FLAIR MRI

    PubMed Central

    2013-01-01

    Background Activity of disease in patients with multiple sclerosis (MS) is monitored by detecting and delineating hyper-intense lesions on MRI scans. The Minimum Area Contour Change (MACC) algorithm has been created with two main goals: a) to improve inter-operator agreement on outlining regions of interest (ROIs) and b) to automatically propagate longitudinal ROIs from the baseline scan to a follow-up scan. Methods The MACC algorithm first identifies an outer bound for the solution path, forms a high number of iso-contour curves based on equally spaced contour values, and then selects the best contour value to outline the lesion. The MACC software was tested on a set of 17 FLAIR MRI images evaluated by a pair of human experts and a longitudinal dataset of 12 pairs of T2-weighted Fluid Attenuated Inversion Recovery (FLAIR) images that had lesion analysis ROIs drawn by a single expert operator. Results In the tests where two human experts evaluated the same MRI images, the MACC program demonstrated that it could markedly reduce inter-operator outline error. In the longitudinal part of the study, the MACC program created ROIs on follow-up scans that were in close agreement to the original expert’s ROIs. Finally, in a post-hoc analysis of 424 follow-up scans 91% of propagated MACC were accepted by an expert and only 9% of the final accepted ROIS had to be created or edited by the expert. Conclusion When used with an expert operator's verification of automatically created ROIs, MACC can be used to improve inter- operator agreement and decrease analysis time, which should improve data collected and analyzed in multicenter clinical trials. PMID:24004511

  13. Spontaneous glomerular sclerosis in aging Sprague-Dawley rats. I. Lesions associated with mesangial IgM deposits.

    PubMed Central

    Bolton, W. K.; Benton, F. R.; Maclay, J. G.; Sturgill, B. C.

    1976-01-01

    The present studies examined the pathogenesis of focal glomerular sclerosis in aging rats. A marked difference in development of the lesion was noted between males and females, and strain variability was an important factor. Increased glomerular basement membrane permeability with loss of selectivity unrelated to changes in glomerular sialoprotein occurred with aging and was accompanied by increasing proteinuria. Noncomplement-fixing mesangial deposits of rat IgM were present after 1 month of age and were also found in lesser amounts in germfree rats. Fluoresceinated eluates of rat kidneys did not have antibody activity against rat serum or tissue antigens. There was no evidence for a pathogenetic role of IgM deposits. Rat IgG, IgA, IgE, C3, and fibrin were occasionally found in sclerotic areas. Analysis of multiple histologic sections revealed a close correlation between aging and glomerular pathology, with a poor correlation between tubular damage and aging. Glomerular damage appeared to be the initial event leading to tubular damage. Indirect evidence suggests that a relative thymic deficiency may play an important role in the pathogenesis of the lesion. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:793408

  14. Higher prevalence of restless legs syndrome/Willis-Ekbom disease in multiple sclerosis patients is related to spinal cord lesions.

    PubMed

    Minár, M; Petrleničová, D; Valkovič, P

    2017-02-01

    Multiple sclerosis (MS) is connected with higher prevalence of secondary restless legs syndrome/Willis-Ekbom disease (RLS/WED). Aim of this study was to determine risk factor for developing symptoms of RLS in MS patients. In cross-sectional study we examined 200 random MS patients. After obtaining informed consents, patients undervent a structured interview based on RLS and MS symptoms and characteristics, demographic, and health-related data. Than we collected results of brain/spinal cord magnetic resonance imaging (MRI). Blood samples were examined for blood count and biochemistry. From all 200 subjects, 26% were RLS-positives (95% CI: 20-32%). From positive patients, 44% had negative family history for RLS, and developed secondary RLS after onset of MS. Compared to RLS-negatives, the positives had significantly higher prevalence of spinal cord lesions (p=0.01). Presence of spinal pathology was connected with higher risk of RLS development (OR=3.846, 95%CI:1.304-11.346). There were no statistically significant differences in the levels of red blood cells, iron metabolism parameters, or levels of B or D vitamins. Risk of RLS/WED in MS increases with presence of lesions in spinal cord. The role of decreased dopamine delivery to lower spinal regions as the pathological background must be proved by more detailed research. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Relating relapse and T2 lesion changes to disability progression in multiple sclerosis: a systematic literature review and regression analysis

    PubMed Central

    2013-01-01

    Background In the treatment of multiple sclerosis (MS), the most important therapeutic aim of disease-modifying treatments (DMTs) is to prevent or postpone long-term disability. Given the typically slow progression observed in the majority of relapsing-remitting MS (RRMS) patients, the primary endpoint for most randomized clinical trials (RCTs) is a reduction in relapse rate. It is widely assumed that reducing relapse rate will slow disability progression. Similarly, MRI studies suggest that reducing T2 lesions will be associated with slowing long-term disability in MS. The objective of this study was to evaluate the relationship between treatment effects on relapse rates and active T2 lesions to differences in disease progression (as measured by the Expanded Disability Status Scale [EDSS]) in trials evaluating patients with clinically isolated syndrome (CIS), RRMS, and secondary progressive MS (SPMS). Methods A systematic literature review was conducted in Medline, Embase, CENTRAL, and PsycINFO to identify randomized trials published in English from January 1, 1993-June 3, 2013 evaluating DMTs in adult MS patients using keywords for CIS, RRMS, and SPMS combined with keywords for relapse and recurrence. Eligible studies were required to report outcomes of relapse and T2 lesion changes or disease progression in CIS, RRMS, or SPMS patients receiving DMTs and have a follow-up duration of at least 22 months. Ultimately, 40 studies satisfied these criteria for inclusion. Regression analyses were conducted on RCTs to relate differences between the effect of treatments on relapse rates and on active T2 lesions to differences between the effects of treatments on disease progression (as measured by EDSS). Results Regression analysis determined there is a substantive clinically and statistically significant association between concurrent treatment effects in relapse rate and EDSS; p < 0.01. Lower treatment effects were associated with higher relative rates of disease

  16. 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.

  17. Brain lesion detection in MRI with fuzzy and geostatistical models.

    PubMed

    Pham, Tuan D

    2010-01-01

    Automated image detection of white matter changes of the brain is essentially helpful in providing a quantitative measure for studying the association of white matter lesions with other types of biomedical data. Such study allows the possibility of several medical hypothesis validations which lead to therapeutic treatment and prevention. This paper presents a new clustering-based segmentation approach for detecting white matter changes in magnetic resonance imaging with particular reference to cognitive decline in the elderly. The proposed method is formulated using the principles of fuzzy c-means algorithm and geostatistics.

  18. Detection of intaoral lesions using a fluorescence camera

    NASA Astrophysics Data System (ADS)

    Thoms, Michael

    2006-02-01

    Optical methods for the detection of carious lesions, calculus and plaque have the advantage of being minimally invasive. The use of endogeneous fluorescence markers like porphyrins could simplify the application of fluorescence techniques in the dental practice. It is known that porphyrins are produced by some of the bacterial species that are present in the oral cavity. Since porphyrins have an excitation band at about 400nm they have the potential to be used as fluorescent markers of locations in the oral cavity where the production of bacteria is out of the limits of healthy regions. Further, modern and efficient GaN-based semiconductor diodes emit light in this spectral range and thus make the implementation of fluorescence sensors with excitation at this wavelength easy. Carious lesions, calculus and plaque have been measured using a self build fluorescence camera using GaN-diodes for illumination at 405nm. Further, emission spectra under this excitation were recorded. For the latter purpose freshly extracted teeth were used. It has been found that already in the case of an initial carious lesion red porphyrin-fluorescence is emitted whereas it is absent in healthy enamel. In already brown coloured carious lesions the emission bands of porphyrin are present but the observed overall fluorescence intensity is lower, probably due to the absorption of the fluorescence by the carious defect itself. In dental calculus, dental plaque and subgingival concrements porphyrin originated luminescence was found as well. Since in these cases the emission spectra differ slightly it can be concluded that they originate from different types of porphyrins and thus also from different bacteria. These results show that this fluorescence technique can be a promising method to diagnose carious lesions, calculus and plaque.

  19. Automated detection of diabetic retinopathy lesions on ultrawidefield pseudocolour images.

    PubMed

    Wang, Kang; Jayadev, Chaitra; Nittala, Muneeswar G; Velaga, Swetha B; Ramachandra, Chaithanya A; Bhaskaranand, Malavika; Bhat, Sandeep; Solanki, Kaushal; Sadda, SriniVas R

    2017-09-19

    We examined the sensitivity and specificity of an automated algorithm for detecting referral-warranted diabetic retinopathy (DR) on Optos ultrawidefield (UWF) pseudocolour images. Patients with diabetes were recruited for UWF imaging. A total of 383 subjects (754 eyes) were enrolled. Nonproliferative DR graded to be moderate or higher on the 5-level International Clinical Diabetic Retinopathy (ICDR) severity scale was considered as grounds for referral. The software automatically detected DR lesions using the previously trained classifiers and classified each image in the test set as referral-warranted or not warranted. Sensitivity, specificity and the area under the receiver operating curve (AUROC) of the algorithm were computed. The automated algorithm achieved a 91.7%/90.3% sensitivity (95% CI 90.1-93.9/80.4-89.4) with a 50.0%/53.6% specificity (95% CI 31.7-72.8/36.5-71.4) for detecting referral-warranted retinopathy at the patient/eye levels, respectively; the AUROC was 0.873/0.851 (95% CI 0.819-0.922/0.804-0.894). Diabetic retinopathy (DR) lesions were detected from Optos pseudocolour UWF images using an automated algorithm. Images were classified as referral-warranted DR with a high degree of sensitivity and moderate specificity. Automated analysis of UWF images could be of value in DR screening programmes and could allow for more complete and accurate disease staging. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  20. 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

  1. Comparison of Diffuse Weighted Imaging and Fluid Attenuation Inversion Recovery Sequences of MRI in Brain Multiple Sclerosis Plaques Detection.

    PubMed

    Nafisi-Moghadam, Reza; Rahimdel, Abolghasem; Shanbehzadeh, Tahereh; Fallah, Razieh

    2017-01-01

    Suitable magnetic resonance imaging (MRI) techniques from conventional to new devices can help physicians in diagnosis and follow up of Multiple Sclerosis (MS) patients. The aim of present research was to compare effectiveness of Fluid Attenuation Inversion Recovery (FLAIR) sequence of conventional MRI and Diffuse Weighted Imaging (DWI) sequence as a new technique in detection of brain MS plaques. In this analytic cross sectional study, sample size was assessed as 40 people to detect any significant difference between two sequences with a level of 0.05. DWI and FLAIR sequences of without contrast brain MRI of consecutive MS patients referred to MRI center of Shahid Sadoughi Hospital, Yazd, Iran from January to May 2012, were evaluated. Thirty-two females and 8 males with mean age of 35.20±9.80 yr (range = 11-66 yr) were evaluated and finally 340 plaques including 127(37.2%) in T2WI, 127(37.2%) in FLAIR, 63(18.5%) in DWI and 24(7.1%) in T1WI were detected. FLAIR sequence was more efficient than DWI in detection of brain MS plaques, oval, round, amorphous plaque shapes, frontal and occipital lobes, periventricular, intracapsular, corpus callosum, centrum semiovale, subcortical, basal ganglia plaques and diameter of detected MS plaques in DWI sequence was smaller than in FLAIR. Old lesion can be detected by conventional MRI and new techniques might be more useful in early inflammatory phase of MS and assessment of experimental treatments.

  2. Multi-parametric MR assessment of T(1) black holes in multiple sclerosis : evidence that myelin loss is not greater in hypointense versus isointense T(1) lesions.

    PubMed

    Vavasour, I M; Li, D K B; Laule, C; Traboulsee, A L; Moore, G R W; Mackay, A L

    2007-12-01

    Chronic T(1) hypointense lesions in multiple sclerosis (MS) are areas of severe tissue destruction. The purpose of this study was to compare total water content (WC),myelin water content (MWC), magnetization transfer ratio (MTR), T(1) relaxation time (T(1)), mean T(2) relaxation time (GMT(2)) between stable MS lesions that are hypointense and isointense on T(1)-weighted images. Six MS patients were scanned five times over one year. WC, MWC, MTR, T(1) and GMT(2) were calculated for 15 isointense and 15 hypointense chronically stable T(1) lesions, as well as contralateral normal appearing white matter (NAWM). All MR measurements from both iso- and hypointense stable lesion types were significantly different from NAWM. WC, T(1) and GMT(2) were significantly higher and MTR significantly lower in hypointense T(1) lesions compared to isointense lesions. MWC was not significantly different between iso- and hypointense lesions. This work suggests that myelin loss occurs equally in both the chronic isointense and hypointense lesions but hypointense lesions are distinguished by increased extracellular water.

  3. 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

  4. Differences in visual naming performance between patients with temporal lobe epilepsy associated with temporopolar lesions versus hippocampal sclerosis.

    PubMed

    Poch, Claudia; Toledano, Rafael; Jiménez-Huete, Adolfo; García-Morales, Irene; Gil-Nagel, Antonio; Campo, Pablo

    2016-10-01

    Naming difficulties are frequently observed in patients with temporal lobe epilepsy (TLE). Although damage/removal of regions of the anterior temporal neocortex including the temporal pole is considered critical for those difficulties, 1 relevant hypothesis proposes that hippocampal damage also has a role. Our aim was to better understand the specific involvement of temporal pole and hippocampus in visual object naming. We assessed 2 types of patients with TLE on a visual confrontation-naming task: patients with hippocampal sclerosis (HS; n = 16) and patients with a lesion on the tip of the temporal pole that spared the hippocampus entirely (n = 18). A common battery of verbal and nonverbal semantic tasks was administered and used as a semantic memory background. Control group were 20 matched healthy participants. Patients with lesions on their temporal poles differed from patients with HS and control group on naming ability, proportion and rate of error type, and influence of concept familiarity. Of note, naming performance was not affected by hippocampal damage. Using a Bayesian model averaging approach, we found that the number of omission errors distinguished patients with temporal pole damage from patients with HS and controls. This differential pattern occurred despite similar impairment on the semantic memory background in both clinical groups. Current findings provide evidence that temporal pole damage produces or contributes to naming impairment in TLE, while also suggesting that the hippocampus is not critical for naming. They also highlight the importance of error-type analysis when evaluating visual naming in TLE. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

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

    PubMed

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

    2013-05-01

    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. 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. 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. 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. ADIMA enabled the simple classification of WML into two groups having different quantitative magnetic resonance properties, which can be reproducibly distinguished.

  6. Everolimus in the treatment of subependymal giant cell astrocytomas, angiomyolipomas, and pulmonary and skin lesions associated with tuberous sclerosis complex

    PubMed Central

    Franz, David Neal

    2013-01-01

    Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder caused by inactivating mutations in either the TSC1 or TSC2 genes. It is characterized by the development of multiple, benign tumors in several organs throughout the body. Lesions occur in the brain, kidneys, heart, liver, lungs, and skin and result in seizures and epilepsy, mental retardation, autism, and renal and pulmonary organ system dysfunction, as well as other complications. Elucidation of the molecular pathways and etiological factors responsible for causing TSC has led to a paradigm shift in the management and treatment of the disease. TSC1 or TSC2 mutations lead to constitutive upregulation of the mammalian target of rapamycin pathway, which affects many cellular processes involved in tumor growth. By targeting mammalian target of rapamycin with everolimus, an orally active rapamycin derivative, clinically meaningful and statistically significant reductions in tumor burden have been achieved for the main brain (subependymal giant cell astrocytoma) and renal manifestations (angiomyolipoma) associated with TSC. This review provides an overview of TSC, everolimus, and the clinical trials that led to its approval for the treatment of TSC-associated subependymal giant cell astrocytoma and renal angiomyolipoma. PMID:24143074

  7. Tuberous sclerosis: a case report.

    PubMed

    Cross, Nicola Jayne; Fung, Diane E

    2010-01-01

    Tuberous sclerosis is an inherited neurocutaneous disorder that occurs in approximately 1 in 7,500 live births. It is characterized by benign neoplasms of the skin, heart, kidneys, lungs, central nervous system, and mucosa. Oral lesions are usually fibrous in nature and most commonly occur on the anterior gingivae. Patients may suffer with epilepsy and learning difficulties, which may complicate dental management. When a 10-year-old girl with a history of tuberous sclerosis was brought in for a routine dental check-up, a leafy growth on the anterior gingiva was detected. An excisional biopsy was carried out. Histologically, the appearance was described as nonspecific, but was consistent with a diagnosis of tuberous sclerosis. Tuberous sclerosis is a rare condition that may exhibit oral manifestations. The patients may also exhibit epilepsy and learning difficulties. Dental management of affected patients may therefore be more complicated and complex.

  8. Feature Selection in Order to Extract Multiple Sclerosis Lesions Automatically in 3D Brain Magnetic Resonance Images Using Combination of Support Vector Machine and Genetic Algorithm

    PubMed Central

    Khotanlou, Hassan; Afrasiabi, Mahlagha

    2012-01-01

    This paper presents a new feature selection approach for automatically extracting multiple sclerosis (MS) lesions in three-dimensional (3D) magnetic resonance (MR) images. Presented method is applicable to different types of MS lesions. In this method, T1, T2, and fluid attenuated inversion recovery (FLAIR) images are firstly preprocessed. In the next phase, effective features to extract MS lesions are selected by using a genetic algorithm (GA). The fitness function of the GA is the Similarity Index (SI) of a support vector machine (SVM) classifier. The results obtained on different types of lesions have been evaluated by comparison with manual segmentations. This algorithm is evaluated on 15 real 3D MR images using several measures. As a result, the SI between MS regions determined by the proposed method and radiologists was 87% on average. Experiments and comparisons with other methods show the effectiveness and the efficiency of the proposed approach. PMID:23724371

  9. Innate immunity in multiple sclerosis white matter lesions: expression of natural cytotoxicity triggering receptor 1 (NCR1).

    PubMed

    Durrenberger, Pascal F; Ettorre, Anna; Kamel, Fatemah; Webb, Louise V; Sim, Malcolm; Nicholas, Richard S; Malik, Omar; Reynolds, Richard; Boyton, Rosemary J; Altmann, Daniel M

    2012-01-02

    Pathogenic or regulatory effects of natural killer (NK) cells are implicated in many autoimmune diseases, but evidence in multiple sclerosis (MS) and its murine models remains equivocal. In an effort to illuminate this, we have here analysed expression of the prototypic NK cell marker, NCR1 (natural cytotoxicity triggering receptor; NKp46; CD335), an activating receptor expressed by virtually all NK cells and therefore considered a pan-marker for NK cells. The only definitive ligand of NCR1 is influenza haemagglutinin, though there are believed to be others. In this study, we investigated whether there were differences in NCR1+ cells in the peripheral blood of MS patients and whether NCR1+ cells are present in white matter lesions. We first investigated the expression of NCR1 on peripheral blood mononuclear cells and found no significant difference between healthy controls and MS patients. We then investigated mRNA levels in central nervous system (CNS) tissue from MS patients: NCR1 transcripts were increased more than 5 times in active disease lesions. However when we performed immunohistochemical staining of this tissue, few NCR1+ NK cells were identified. Rather, the major part of NCR1 expression was localised to astrocytes, and was considerably more pronounced in MS patients than controls. In order to further validate de novo expression of NCR1 in astrocytes, we used an in vitro staining of the human astrocytoma U251 cell line grown to model whether cell stress could be associated with expression of NCR1. We found up-regulation of NCR1 expression in U251 cells at both the mRNA and protein levels. The data presented here show very limited expression of NCR1+ NK cells in MS lesions, the majority of NCR1 expression being accounted for by expression on astrocytes. This is compatible with a role of this cell-type and NCR1 ligand/receptor interactions in the innate immune response in the CNS in MS patients. This is the first report of NCR1 expression on astrocytes in

  10. Daclizumab high-yield process reduced the evolution of new gadolinium-enhancing lesions to T1 black holes in patients with relapsing-remitting multiple sclerosis.

    PubMed

    Radue, E-W; Sprenger, T; Vollmer, T; Giovannoni, G; Gold, R; Havrdova, E; Selmaj, K; Stefoski, D; You, X; Elkins, J

    2016-02-01

    In the SELECT study, treatment with daclizumab high-yield process (DAC HYP) versus placebo reduced the frequency of gadolinium-enhancing (Gd(+) ) lesions in patients with relapsing-remitting multiple sclerosis (RRMS). The objective of this post hoc analysis of SELECT was to evaluate the effect of DAC HYP on the evolution of new Gd(+) lesions to T1 hypointense lesions (T1 black holes). SELECT was a randomized double-blind study of subcutaneous DAC HYP 150 or 300 mg or placebo every 4 weeks. Magnetic resonance imaging (MRI) scans were performed at baseline and weeks 24, 36 and 52 in all patients and monthly between weeks 4 and 20 in a subset of patients. MRI scans were evaluated for new Gd(+) lesions that evolved to T1 black holes at week 52. Data for the DAC HYP groups were pooled for analysis. Daclizumab high-yield process reduced the number of new Gd(+) lesions present at week 24 (P = 0.005) or between weeks 4 and 20 (P = 0.014) that evolved into T1 black holes at week 52 versus placebo. DAC HYP treatment also reduced the percentage of patients with Gd(+) lesions evolving to T1 black holes versus placebo. Treatment with DAC HYP reduced the evolution of Gd(+) lesions to T1 black holes versus placebo, suggesting that inflammatory lesions that evolved during DAC HYP treatment are less destructive than those evolving during placebo treatment. © 2016 EAN.

  11. Detectability of artificial lesions in anthropomorphic virtual breast phantoms of variable glandular fraction

    NASA Astrophysics Data System (ADS)

    Sauer, Thomas J.; Graff, Christian G.; Zeng, Rongping; Santana, Maira; Sturgeon, Gregory M.; Bosmans, Hilde; Glick, Stephen J.; Chen, Xinyuan C.; Segars, W. P.; Lo, Joseph Y.

    2017-03-01

    This work seeks to utilize a cohort of computational, patient-based breast phantoms and anthropomorphic lesions inserted therein to determine trends in breast lesion detectability as a function of several clinically relevant variables. One of the measures of local density proposed gives rise to a statistically significant trend in lesion detectability, and it is apparent that lesion type is also a predictor of relative detectability.

  12. The relationship between infratentorial lesions, balance deficit and accidental falls in multiple sclerosis.

    PubMed

    Prosperini, Luca; Kouleridou, Anna; Petsas, Nikolaos; Leonardi, Laura; Tona, Francesca; Pantano, Patrizia; Pozzilli, Carlo

    2011-05-15

    The role of static posturography and magnetic resonance imaging (MRI) in identifying patients at high risk of falls was investigated. Relationships between static posturography measures and MRI metrics were also investigated. A total of 31 ambulatory MS patients (EDSS ranging from 2.0 to 5.0) with a predominant balance disorder were recruited. Each patient underwent a static posturography with a monoaxial platform and a conventional 1.5 T brain MRI scan. Measurements of T1-hypointense and T2-hyperintense lesion volumes (LVs), focusing on lesions selectively located at infratentorial levels, were performed by two operators unaware of clinical data. The self-reported number of falls in the previous 6 months was considered as the main outcome measure. Fourteen (45%) patients reported 1 or more falls over the past 6 months. When compared to non-faller patients, they had a higher EDSS score, poorer static standing balance, and greater brainstem and middle cerebellar peduncle (MCP) T2-LVs. A strength correlation between brainstem T2-LV and impaired static standing balance in an open eye condition was also found. In the multivariate analysis, the variables more strictly associated with recurrent falls were greater T2-LV at the MCP (beta: 6.2; p=0.01) and brainstem (beta: 5.8; p=0.001) levels, and a wider displacement of the body center of pressure in the closed eye condition (beta: 0.02; p=0.03). Our data suggests that the damage of specific infratentorial areas negatively affect the static standing balance and may predispose MS patients to accidental falls. These findings might contribute in selecting patients requiring a proper rehabilitation intervention program. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. 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

  14. 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.

  15. Automated detection of dark and bright lesions in retinal images for early detection of diabetic retinopathy.

    PubMed

    Akram, Usman M; Khan, Shoab A

    2012-10-01

    There is an ever-increasing interest in the development of automatic medical diagnosis systems due to the advancement in computing technology and also to improve the service by medical community. The knowledge about health and disease is required for reliable and accurate medical diagnosis. Diabetic Retinopathy (DR) is one of the most common causes of blindness and it can be prevented if detected and treated early. DR has different signs and the most distinctive are microaneurysm and haemorrhage which are dark lesions and hard exudates and cotton wool spots which are bright lesions. Location and structure of blood vessels and optic disk play important role in accurate detection and classification of dark and bright lesions for early detection of DR. In this article, we propose a computer aided system for the early detection of DR. The article presents algorithms for retinal image preprocessing, blood vessel enhancement and segmentation and optic disk localization and detection which eventually lead to detection of different DR lesions using proposed hybrid fuzzy classifier. The developed methods are tested on four different publicly available databases. The presented methods are compared with recently published methods and the results show that presented methods outperform all others.

  16. Recommendations for the detection and therapeutic management of cognitive impairment in multiple sclerosis.

    PubMed

    Bensa, C; Bodiguel, E; Brassat, D; Laplaud, D; Magy, L; Ouallet, J-C; Zephir, H; De Seze, J; Blanc, F

    2012-11-01

    The aim of the Multiple Sclerosis Think Tank (Groupe de réflexion sur la sclérose en plaques [GRESEP]) is to prescribe recommendations following a systematic literature search and using a Rand Corporation and California University (RAND/UCLA) appropriateness derived method, in response to practical questions that are raised in the management of patients with multiple sclerosis (MS). The topics of this working program were chosen because they were not addressed in the French recommendations and because of the few data in the literature that enabled practices to be based on validated data. Following the theme on useful serum testing with suspected multiple sclerosis, the subjects of the present work concern the detection and management of cognitive impairment in the beginning stages of the disease course. Two clinical questions were asked: which complementary exams (besides physical examination and neuropsychological tests) would help in the screening of cognitive impairment at the beginning of the disease? What care management should the person with MS and cognitive impairment be offered (treatments and neurocognitive rehabilitation)? The recommendations are the result of a consensus amongst a working group, a rating group and a reading group comprised of hospital neurologists involved in the management of patients with multiple sclerosis. Each recommendation is presented with the degree of consensus that it was accorded.

  17. [Demand for abortion. Detection of cervical cancer and precancerous lesions].

    PubMed

    Benmoura, D

    1994-03-01

    Eighteen years of experience with cervical screening in the Center for Social Gynecology in Marseilles has demonstrated the existence of a group at high risk of cervical dysplasia. Its characteristics are early initiation of sexual activity, sexually transmitted disease, sexual promiscuity, and an unfavorable socioeconomic environment. Precancerous lesions are sometimes observed before the age of 18. Pap tests are done during preabortion consultations at the Center except in very young patients, those who are too emotionally distressed, and those with inflammations from vaginitis. The test may be done before the abortion because in the first trimester the cells do not yet show changes that would interfere with interpretation of the Pap smear. Bleeding after the abortion interferes with reading the slide. Results of 405 Pap tests conducted during a reference period from August 1992 to July 1993 among women seeking abortions at the Center for Social Gynecology were compared to those of 1601 women undergoing gynecological examinations at two other centers. Among patients at the Center for Social Gynecology and the other two centers respectively, 3.5% and 1.4% were diagnosed with condylomas, 1.5% and 1.2% with dysplasia, and 1.25% and 0.5% with condylomas and dysplasia. During the reference period, only 20% of women were screened. The number of lesions detected suggests that a higher proportion of women should be screened in this population of women often lacking regular medical care.

  18. Impairment of visuospatial/visuoconstructional skills in multiple sclerosis patients: the correlation with regional lesion load and subcortical atrophy.

    PubMed

    Marasescu, R; Cerezo Garcia, M; Aladro Benito, Y

    2016-04-01

    About 20% to 26% of patients with multiple sclerosis (MS) show alterations in visuospatial/visuoconstructive (VS-VC) skills even though temporo-parieto-occipital impairment is a frequent finding in magnetic resonance imaging. No studies have specifically analysed the relationship between these functions and lesion volume (LV) in these specific brain areas. To evaluate the relationship between VS-VC impairment and magnetic resonance imaging temporo-parieto-occipital LV with subcortical atrophy in patients with MS. Of 100 MS patients undergoing a routine neuropsychological evaluation, 21 were selected because they displayed VS-VC impairments in the following tests: Incomplete picture, Block design (WAIS-III), and Rey-Osterrieth complex figure test. We also selected 13 MS patients without cognitive impairment (control group). Regional LV was measured in FLAIR and T1-weighted images using a semiautomated method; subcortical atrophy was measured by bicaudate ratio and third ventricle width. Partial correlations (controlling for age and years of school) and linear regression analysis were employed to analyse correlations between magnetic resonance imaging parameters and cognitive performance. All measures of LV and brain atrophy were significantly higher in patients with cognitive impairment. Regional LV, bicaudate ratio, and third ventricle width are significantly and inversely correlated with cognitive performance; the strongest correlation was between third ventricle width and VC performance (Block design: P=.001; Rey-Osterrieth complex figure: P<.000). In the multivariate analysis, third ventricle width only had a significant effect on performance of VC tasks (Block design: P=.000; Rey-Osterrieth complex figure: P=.000), and regional FLAIR VL was linked to the VS task (Incomplete picture; P=.002). Measures of subcortical atrophy explain the variations in performance on visuocostructive tasks, and regional FLAIR VL measures are linked to VS tasks. Copyright © 2015

  19. Detection of Brain Reorganization in Pediatric Multiple Sclerosis Using Functional MRI

    DTIC Science & Technology

    2015-10-01

    delayed due to backlog in MRI scanning of patients and volunteers at our institution—we are behind schedule in recruiting and collecting data in 10 of...the MRI scanners at our institution, and slower than expected recruitment of eligible POMS patients from the MS clinic. Recruitment and fMRI scanning ...Page | 2 AWARD NUMBER: W81XWH-13-1-0464 TITLE: Detection of Brain Reorganization in Pediatric Multiple Sclerosis Using Functional MRI

  20. Significance of incidentally detected subcentimeter enhancing lesions on preoperative breast MRI: role of second-look ultrasound in lesion detection and management.

    PubMed

    Nam, Se Jin; Kim, Eun-Kyung; Kim, Min Jung; Moon, Hee Jung; Yoon, Jung Hyun

    2015-03-01

    OBJECTIVE. The purpose of this article is to evaluate the clinical significance of subcentimeter enhancing lesions incidentally detected on preoperative breast MRI in patients with breast cancer and the role of second-look ultrasound in lesion detection and characterization. MATERIALS AND METHODS. From January 2010 through December 2010, 180 lesions measuring less than 10 mm incidentally detected on MRI in 108 women with second-look ultrasound examinations were included (mean patient age, 47.9 years; mean [± SD] lesion size, 5.56 ± 1.64 mm). Seventy-two (40.0%) lesions were smaller than 5 mm, and 108 (60.0%) were 5 mm or larger. Of the 180 lesions, 103 (57.2%) had been biopsied or excised by localization, and 77 (42.8%) with benign ultrasound features had been followed with ultrasound for at least 2 years. Clinical and imaging features were recorded for analysis. RESULTS. Of the 180 enhancing lesions detected on MRI, 14 (7.8%) were malignant and 166 (92.2%) were benign. The malignancy rate of lesions 5 mm or larger was higher than that for lesions smaller than 5 mm (10.2% vs 4.2%), without statistical significance (p = 0.344). The washout enhancement pattern was statistically significantly associated with malignancy (p = 0.032). Although malignant ultrasound features such as nonparallel orientation were more common in malignant lesions, most malignancies had benign features, including oval shape, parallel orientation, and circumscribed margins, with BI-RADS category 4a (n = 12; 85.8%) as the final assessment. CONCLUSION. Second-look ultrasound is a feasible method for evaluating MRI-detected subcentimeter sized lesions in preoperative assessment of patients with breast cancer. A lower threshold should be applied with consideration of MRI features in deciding whether to biopsy or excise these lesions.

  1. 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

  2. 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.

  3. 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.

  4. Comparison of radiography and ultrasonography to detect osteochondrosis lesions in the tarsocrural joint: a prospective study.

    PubMed

    Relave, F; Meulyzer, M; Alexander, K; Beauchamp, G; Marcoux, M

    2009-01-01

    Lesions located on the medial malleolus of the tarsocrural joint can be difficult to image radiographically. Ultrasonography allows evaluation of articular cartilage and subchondral bone. To compare dorso30 degrees lateral-plantaromedial-oblique (DL-PIMO) and dorso45 degrees views to detect lesions on the medial malleolus, to validate the use of ultrasonography to show lesions in the tarsocrural joint and to compare its sensitivity to radiography. Tarsocrural joints (n=111) with osteochondrosis were evaluated ultrasonographically and radiographically prior to arthroscopic lesion debridement. A complete radiographic examination was made and the best view to detect each lesion recorded. Longitudinal and transverse ultrasonography of the dorsal aspect of the joint was performed and the best scan plane to image each lesion recorded. There were 94 joints with lesions on the distal intermediate ridge of tibia, 24 with lesions on the medial malleolus, and 4 with lesions on the lateral trochlear ridge. The sensitivity of radiography to detect lesions on the medial malleolus and distal intermediate ridge of tibia was 71 and 96%, respectively. Eighty-two percent of lesions on the medial malleolus were better imaged on dorso30 degrees view. The sensitivity of ultrasonography to detect lesions on the medial malleolus and distal intermediate ridge of tibia was 83 and 98%, respectively. Ultrasonography was significantly more sensitive than radiography to detect lesions on the medial malleolus and distal intermediate ridge of tibia. Dorso30 degrees lateral-plantaromedial-oblique view was the best to image lesions on the medial malleolus. Ultrasonography was a valuable diagnostic tool to diagnose lesions in the tarsocrural joint and was more sensitive than radiography for lesions located on the medial malleolus and distal intermediate ridge of tibia. Radiographic examination should include a dorso30 degrees view for detection of lesions on the medial malleolus and ultrasonography

  5. 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.

  6. Evaluation of penalty design in penalized maximum-likelihood image reconstruction for lesion detection

    NASA Astrophysics Data System (ADS)

    Yang, Li; Ferrero, Andrea; Hagge, Rosalie J.; Badawi, Ramsey D.; Qi, Jinyi

    2014-03-01

    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, where we used a multiview channelized Hotelling observer (mvCHO) to assess the lesion detectability in 3D images. It mimics the condition where a human observer examines three orthogonal views of a 3D image for lesion detection. We proposed a method to design a shift-variant quadratic penalty function to improve the detectability of lesions at unknown locations, and validated it using computer simulations. In this study we evaluated the bene t of the proposed penalty function for lesion detection using real data. A high-count real patient data with no identi able tumor inside the eld of view was used as the background data. A Na-22 point source was scanned in air at variable locations and the point source data were superimposed onto the patient data as arti cial lesions after being attenuated by the patient body. Independent Poisson noise was added to the high-count sinograms to generate 200 pairs of lesion-present and lesion-absent data sets, each mimicking a 5-minute scans. Lesion detectability was assessed using a multiview CHO and a human observer two alternative forced choice (2AFC) experiment. The results showed that the optimized penalty can improve lesion detection over the conventional quadratic penalty function.

  7. Detection and quantification of regional cortical gray matter damage in multiple sclerosis utilizing gradient echo MRI.

    PubMed

    Wen, Jie; Yablonskiy, Dmitriy A; Luo, Jie; Lancia, Samantha; Hildebolt, Charles; Cross, Anne H

    2015-01-01

    Cortical gray matter (GM) damage is now widely recognized in multiple sclerosis (MS). The standard MRI does not reliably detect cortical GM lesions, although cortical volume loss can be measured. In this study, we demonstrate that the gradient echo MRI can reliably and quantitatively assess cortical GM damage in MS patients using standard clinical scanners. High resolution multi-gradient echo MRI was used for regional mapping of tissue-specific MRI signal transverse relaxation rate values (R2(*)) in 10 each relapsing-remitting, primary-progressive and secondary-progressive MS subjects. A voxel spread function method was used to correct artifacts induced by background field gradients. R2(*) values from healthy controls (HCs) of varying ages were obtained to establish baseline data and calculate ΔR2(*) values - age-adjusted differences between MS patients and HC. Thickness of cortical regions was also measured in all subjects. In cortical regions, ΔR2(*) values of MS patients were also adjusted for changes in cortical thickness. Symbol digit modalities (SDMT) and paced auditory serial addition (PASAT) neurocognitive tests, as well as Expanded Disability Status Score, 25-foot timed walk and nine-hole peg test results were also obtained on all MS subjects. We found that ΔR2(*) values were lower in multiple cortical GM and normal appearing white matter (NAWM) regions in MS compared with HC. ΔR2(*) values of global cortical GM and several specific cortical regions showed significant (p < 0.05) correlations with SDMT and PASAT scores, and showed better correlations than volumetric measures of the same regions. Neurological tests not focused on cognition (Expanded Disability Status Score, 25-foot timed walk and nine-hole peg tests) showed no correlation with cortical GM ΔR2(*) values. The technique presented here is robust and reproducible. It requires less than 10 min and can be implemented on any MRI scanner. Our results show that quantitative tissue-specific R2

  8. A method for mass candidate detection and an application to liver lesion detection

    NASA Astrophysics Data System (ADS)

    Costa, Maria J.; Tsymbal, Alexey; Nguatem, William; Suehling, Michael; Zhou, S. Kevin; Comaniciu, Dorin

    2011-03-01

    Detection and segmentation of abnormal masses within organs in Computed Tomography (CT) images of patients is of practical importance in computer-aided diagnosis (CAD), treatment planning, and analysis of normal as well as pathological regions. For intervention planning e.g. in radiotherapy the detection of abnormal masses is essential for patient diagnosis, personalized treatment choice and follow-up. The unpredictable nature of disease often makes the detection of the presence, appearance, shape, size and number of abnormal masses a challenging task, which is particularly tedious when performed by hand. Moreover, in cases in which the imaging protocol specifies the administration of a contrast agent, the contrast agent phases at which the patient images are acquired have a dramatic influence on the shape and appearance of the diseased masses. In this paper we propose a method to automatically detect candidate lesions (CLs) in 3D CTs of liver lesions. We introduce a novel multilevel candidate generation method that proves clearly advantageous in a comparative study with a state of the art approach. A learning-based selection module and a candidate fusion module are then introduced to reduce both redundancy and the false positive rate. The proposed workflow is applied to the detection of both hyperdense and hypodense hepatic lesions in all contrast agent phases, with resulting sensitivities of 89.7% and 92% and positive predictive values of 82.6% and 87.6% respectively.

  9. Hypersexuality, fetishism and multiple sclerosis.

    PubMed

    Huws, R; Shubsachs, A P; Taylor, P J

    1991-02-01

    Hypersexuality and fetishism appeared in a patient with multiple sclerosis whose MRI scan showed frontal and temporal lesions. The hypersexuality may have been the presenting symptom of the multiple sclerosis.

  10. Comparison of Diffuse Weighted Imaging and Fluid Attenuation Inversion Recovery Sequences of MRI in Brain Multiple Sclerosis Plaques Detection

    PubMed Central

    NAFISI-MOGHADAM, Reza; RAHIMDEL, Abolghasem; SHANBEHZADEH, Tahereh; FALLAH, Razieh

    2017-01-01

    Objective Suitable magnetic resonance imaging (MRI) techniques from conventional to new devices can help physicians in diagnosis and follow up of Multiple Sclerosis (MS) patients. The aim of present research was to compare effectiveness of Fluid Attenuation Inversion Recovery (FLAIR) sequence of conventional MRI and Diffuse Weighted Imaging (DWI) sequence as a new technique in detection of brain MS plaques. Materials & Methods In this analytic cross sectional study, sample size was assessed as 40 people to detect any significant difference between two sequences with a level of 0.05. DWI and FLAIR sequences of without contrast brain MRI of consecutive MS patients referred to MRI center of Shahid Sadoughi Hospital, Yazd, Iran from January to May 2012, were evaluated. Results Thirty-two females and 8 males with mean age of 35.20±9.80 yr (range = 11-66 yr) were evaluated and finally 340 plaques including 127(37.2%) in T2WI, 127(37.2%) in FLAIR, 63(18.5%) in DWI and 24(7.1%) in T1WI were detected. FLAIR sequence was more efficient than DWI in detection of brain MS plaques, oval, round, amorphous plaque shapes, frontal and occipital lobes, periventricular, intracapsular, corpus callosum, centrum semiovale, subcortical, basal ganglia plaques and diameter of detected MS plaques in DWI sequence was smaller than in FLAIR. Conclusion Old lesion can be detected by conventional MRI and new techniques might be more useful in early inflammatory phase of MS and assessment of experimental treatments. PMID:28277551

  11. A Channelized Hotelling Observer Study of Lesion Detection in SPECT MAP Reconstruction Using Anatomical Priors

    PubMed Central

    Kulkarni, S.; Khurd, P.; Hsiao, I.; Zhou, L.; Gindi, G.

    2010-01-01

    In emission tomography, anatomical side information, in the form of organ and lesion boundaries, derived from intra-patient coregistered CT or MR scans can be incorporated into the reconstruction. Our interest is in exploring the efficacy of such side information for lesion detectability. To assess detectability we used the SNR of a channelized Hotelling observer and a signal-known exactly/background known exactly detection task. In simulation studies we incorporated anatomical side information into a SPECT MAP (maximum a posteriori) reconstruction by smoothing within but not across organ or lesion boundaries. A non-anatomical prior was applied by uniform smoothing across the entire image. We investigated whether the use of anatomical priors with organ boundaries alone or with perfect lesion boundaries alone would change lesion detectability relative to the case of a prior with no anatomical information. Furthermore, we investigated whether any such detectability changes for the organ-boundary case would be a function of the distance of the lesion to the organ boundary. We also investigated whether any detectability changes for the lesion-boundary case would be a function of the degree of proximity, i.e. a difference in the radius of the true functional lesion and the radius of the anatomical lesion boundary. Our results showed almost no detectability difference with vs without organ boundaries at any lesion-to-organ boundary distance. Our results also showed no difference in lesion detectability with and without lesion boundaries, and no variation of lesion detectability with degree of proximity. PMID:17664562

  12. 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.

  13. Quantitative Susceptibility Mapping and R2* Measured Changes during White Matter Lesion Development in Multiple Sclerosis: Myelin Breakdown, Myelin Debris Degradation and Removal, and Iron Accumulation.

    PubMed

    Zhang, Y; Gauthier, S A; Gupta, A; Chen, W; Comunale, J; Chiang, G C-Y; Zhou, D; Askin, G; Zhu, W; Pitt, D; Wang, Y

    2016-09-01

    Quantitative susceptibility mapping and R2* are sensitive to myelin and iron changes in multiple sclerosis lesions. This study was designed to characterize lesion changes on quantitative susceptibility mapping and R2* at various gadolinium-enhancement stages. This study included 64 patients with MS with different enhancing patterns in white matter lesions: nodular, shell-like, nonenhancing < 1 year old, and nonenhancing 1-3 years old. These represent acute, late acute, early chronic, and late chronic lesions, respectively. Susceptibility values measured on quantitative susceptibility mapping and R2* values were compared among the 4 lesion types. Their differences were assessed with a generalized estimating equation, controlling for Expanded Disability Status Scale score, age, and disease duration. We analyzed 203 lesions: 80 were nodular-enhancing, of which 77 (96.2%) were isointense on quantitative susceptibility mapping; 33 were shell-enhancing, of which 30 (90.9%) were hyperintense on quantitative susceptibility mapping; and 49 were nonenhancing lesions < 1 year old and 41 were nonenhancing lesions 1-3 years old, all of which were hyperintense on quantitative susceptibility mapping. Their relative susceptibility/R2* values were 0.5 ± 4.4 parts per billion/-5.6 ± 2.9 Hz, 10.2 ± 5.4 parts per billion/-8.0 ± 2.6 Hz, 20.2 ± 7.8 parts per billion/-3.1 ± 2.3 Hz, and 33.2 ± 8.2 parts per billion/-2.0 ± 2.6 Hz, respectively, and were significantly different (P < .005). Early active MS lesions with nodular enhancement show R2* decrease but no quantitative susceptibility mapping change, reflecting myelin breakdown; late active lesions with peripheral enhancement show R2* decrease and quantitative susceptibility mapping increase in the lesion center, reflecting further degradation and removal of myelin debris; and early or late chronic nonenhancing lesions show both quantitative susceptibility mapping and R2* increase, reflecting iron accumulation. © 2016 by

  14. 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.

  15. Expression of the Nogo-A system in cortical lesions of pediatric patients with tuberous sclerosis complex and focal cortical dysplasia type IIb.

    PubMed

    Yu, Si-Xun; Li, Song; Shu, Hai-Feng; Zhang, Chun-Qing; Liu, Shi-Yong; Yang, Hui

    2012-07-01

    The reticulon protein Nogo-A is an important regulator of neurite growth, axonal plasticity, and cell migration in the central nervous system. Previous studies have shown markedly elevated levels of Nogo-A in human temporal lobe epilepsy. In the present study, we examined the expression pattern of the Nogo-A system in cortical lesions of pediatric patients with tuberous sclerosis complex and focal cortical dysplasia type IIb. These disorders are characterized by malformations of cortical development and are frequently associated with intractable epilepsy. We found that the messenger RNA and protein levels of the Nogo-A receptor (NgR) and the downstream targets of Nogo-A, LINGO-1, TROY, and RhoA but not P75 were upregulated in the cortices of patients compared with autopsy control samples. Immunohistochemical analyses indicated that Nogo-A and NgR were strongly expressed in misshapen cells, particularly dysmorphic neurons, balloon cells, and giant cells. TROY was diffusely expressed in the malformations of cortical development. Most of theNogo-A/NgR-positive misshapen cells were colabeled with neuronal rather than astrocytic markers. Taken together, our results suggestthat the activation of Nogo-A via the NgR/LINGO-1/TROY signal transduction pathways, but not NgR/LINGO-1/P75, may be involved in the development and/or seizure activity of cortical lesions in tuberous sclerosis complex and focal cortical dysplasia type IIb.

  16. Brain MRI lesion load quantification in multiple sclerosis: a comparison between automated multispectral and semi-automated thresholding computer-assisted techniques.

    PubMed

    Achiron, Anat; Gicquel, Sebastien; Miron, Shmuel; Faibel, Meir

    2002-12-01

    Brain magnetic resonance imaging (MRI) lesion volume measurement is an advantageous tool for assessing disease burden in multiple sclerosis (MS). We have evaluated two computer-assisted techniques: MSA multispectral automatic technique that is based on bayesian classification of brain tissue and NIH image analysis technique that is based on local (lesion by lesion) thresholding, to establish reliability and repeatability values for each technique. Brain MRIs were obtained for 30 clinically definite relapsing-remitting MS patients using a 2.0 Tesla MR scanner with contiguous, 3 mm thick axial, T1, T2 and PD weighted modalities. Digital (Dicom 3) images were analyzed independently by three observers; each analyzed the images twice, using the two different techniques (Total 360 analyses). Accuracy of lesion load measurements using phantom images of known volumes showed significantly better results for the MSA multispectral technique (p < 0.001). The mean intra-and inter-observer variances were, respectively, 0.04 +/- 0.4 (range 0.04-0.13), and 0.09 +/- 0.6 (range 0.01-0.26) for the multispectral MSA analysis technique, 0.24 +/- 2.27 (range 0.23-0.72) and 0.33 +/- 3.8 (range 0.47-1.36) for the NIH threshold technique. These data show that the MSA multispectral technique is significantly more accurate in lesion volume measurements, with better results of within and between observers' assessments, and the lesion load measurements are not influenced by increased disease burden. Measurements by the MSA multispectral technique were also faster and decreased analysis time by 43%. The MSA multispectral technique is a promising tool for evaluating MS patients. Non-biased recognition and delineation algorithms enable high accuracy, low intra-and inter-observer variances and fast assessment of MS related lesion load.

  17. 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.

  18. Volume Navigation Technique for Ultrasound-Guided Biopsy of Breast Lesions Detected Only at MRI.

    PubMed

    Aribal, Erkin; Tureli, Derya; Kucukkaya, Fikret; Kaya, Handan

    2017-06-01

    The purpose of this study is to assess the utility of a volume navigation technique (VNT) for ultrasound-guided biopsy of MRI-detected, but sonographically ambiguous or occult, breast lesions. Within a recruitment period of 13 months (January 1, 2014, through February 1, 2015), 22 patients with 26 BI-RADS category 4 or 5 lesions that were detected at MRI but missed at second-look ultrasound were reimaged using a rapid sequence and a flexible body coil in a 3-T MRI scanner. Patients were supine, with three skin markers placed on the breasts. MRI volume data were coregistered to real-time ultrasound in a dedicated platform, and MRI-detected lesions (six masses, 11 nonmass enhancements, eight foci, and one architectural distortion) were sought using VNT-guided ultrasound. Five needle biopsy specimens were obtained either from each sonographically detected lesion (n = 11) or from VNT-guided sonographically localized breast volume corresponding to the MRI-detected, but still ultrasound-occult, lesions (n = 15). Histopathologic analysis revealed 18 benign and six malignant lesions. The remaining two lesions, both of which appeared as masses at MRI, were high risk and were upgraded to carcinoma after excisional biopsy. All malignant lesions underwent curative surgery; the final histopathologic diagnoses remained unchanged. Of the six malignant lesions, one was a mass, three were nonmass enhancements, and two were enhancing foci at MRI. Three malignant lesions were occult at ultrasound, and three were discerned as subtle hypoechoic changes. No benign lesion was sonographically visualized as a mass, and none progressed, with 56% disappearing at MRI performed during the follow-up period (mean, 14 months). Coregistration of MRI and real-time ultrasound enables sonographic localization of breast lesions detected at MRI only. VNT is a feasible alternative to MRI-guided biopsy of ultrasound-occult breast lesions.

  19. RNA aptamer against autoantibodies associated with multiple sclerosis and bioluminescent detection probe on its basis.

    PubMed

    Vorobjeva, Maria A; Krasitskaya, Vasilisa V; Fokina, Alesya A; Timoshenko, Valentina V; Nevinsky, Georgy A; Venyaminova, Alya G; Frank, Ludmila A

    2014-03-04

    Nowadays, there are no specific laboratory tests for establishing the diagnosis of multiple sclerosis (MS). The presence of proteolytic autoantibodies against myelin basic protein is now considered as a characteristic feature of MS. New 2'-F-containing RNA aptamer of high affinity and specificity to these antibodies was selected. Covalent conjugate of this aptamer and Ca(2+)-regulated photoprotein obelin was obtained for the first time and applied as a label in bioluminescent microplate assay to detect target antibodies. The developed model solid-phase microassay is simple, fast, and highly sensitive.

  20. Intestinal lesions in pediatric Crohn disease: comparative detectability among pulse sequences at MR enterography.

    PubMed

    Sohn, Beomseok; Kim, Myung-Joon; Koh, Hong; Han, Kyung Hwa; Lee, Mi-Jung

    2014-07-01

    Variable sequences can be used in MR enterography, and no consensus exists for the best protocol in children with Crohn disease. To compare the lesion detectability of various MR enterography sequences and to correlate the findings of these sequences with the Pediatric Crohn's Disease Activity Index (PCDAI) in children with Crohn disease. Children with clinically or pathologically confirmed Crohn disease underwent MR enterography, including a single-shot fast spin-echo (SSFSE) sequence, motility imaging (coronal 2-D balanced fast field echo), diffusion-weighted imaging (DWI), and dynamic contrast enhancement imaging (including arterial, portal and delayed phases). The lesion detectability of each sequence was graded 0-2 for each involved bowel segment. The lesion detectability and PCDAI result on different sequences were compared using the weighted least squares method and Student's t-test, respectively. Fifteen children (11 boys, 4 girls, mean age 13.7 ± 1.4 years) with a total of 41 lesions were included in this study. All lesions detected in more than two sequences were visible on the single-shot fast spin-echo (SSFSE) sequence. The relative lesion detection rate was 78.1% on motility imaging, 90.2% on DWI, and 92.7% on arterial, 95.1% on portal and 95.1% on delayed phase imaging. Compared to the SSFSE sequence, motility imaging (P < 0.001) and DWI (P = 0.039) demonstrated lower detectability. The mean PCDAI result in the detected lesions was statistically higher only on dynamic enhancement imaging (P < 0.001). All MR enterography sequences were found to have relatively high lesion detectability in children with Crohn disease, while motility imaging showed the lowest lesion detectability. Lesions detected on dynamic enhancement imaging showed a higher PCDAI result, which suggests that this sequence is specific for active inflammation.

  1. Surgical pathology of epilepsy-associated non-neoplastic cerebral lesions: a brief introduction with special reference to hippocampal sclerosis and focal cortical dysplasia

    PubMed Central

    Miyata, Hajime; Hori, Tomokatsu; Vinters, Harry V.

    2014-01-01

    Among epilepsy-associated non-neoplastic lesions, mesial temporal lobe epilepsy with hippocampal sclerosis (mTLE-HS) and malformation of cortical development (MCD) including focal cortical dysplasia (FCD), are the two most frequent causes of drug-resistant focal epilepsies constituting about 50% of all surgical pathology of epilepsy. Several distinct histological patterns have been historically recognized in both HS and FCD, and several studies have tried to perform clinicopathological correlation; results, however, have been controversial, particularly in terms of postsurgical seizure outcome. Recently, the International League Against Epilepsy constituted a Task Forces of Neuropathology and FCD within the Commission on Diagnostic Methods, to establish an international consensus of histological classification of HS and FCD, respectively, based on agreement with the recognition of the importance of defining a histopathological classification system that reliably has some clinicopathological correlation. Such consensus classifications are likely to facilitate future clinicopathological study. Meanwhile, we reviewed neuropathology of 41 surgical cases of mTLE, and confirmed three type/patterns of HS along with no HS, based on the qualitative evaluation of the distribution and severity of neuronal loss and gliosis within hippocampal formation; i.e., HS type 1 (61%) equivalent to ‘classical’ Ammon’s horn sclerosis, HS type 2 (2%) representing CA1 sclerosis, HS type 3 (17%) equivalent to end folium sclerosis, and no HS (19%). Furthermore we performed a neuropathological comparative study on mTLE-HS and dementia associated HS (d-HS) in elderly, and confirmed that neuropathological features differ between mTLE-HS and d-HS in the distribution of hippocampal neuronal loss and gliosis, morphology of reactive astrocytes and their protein expression, and presence of concomitant neurodegenerative changes particularly Alzheimer type and TDP-43 pathologies. These

  2. Low-contrast focal lesion detectability phantom for 1H MR imaging.

    PubMed

    Madsen, E L; Blechinger, J C; Frank, G R

    1991-01-01

    A phantom made from tissue-mimicking materials is reported for testing 1H MRI systems regarding their ability to detect small low-contrast focal lesions and to delineate the boundaries of larger lesions. Two sets of seven spherical simulated lesions with diameters of 2, 3, 4, 5, 6.3, 7.9, and 9.5 mm have T1 and T2 values somewhat higher than the corresponding values in the surrounding simulated normal tissue. Relaxometer determinations of T1 and T2 for the simulated normal tissue yielded 955 and 106 ms, respectively, at 22 degrees C and 1 T. The corresponding values in set #1 of the simulated lesions were 1017 and 175 ms and in set #2 were 1002 and 127 ms. These T1 and T2 values are similar to those for brain and brain lesions but are too high to represent soft tissue such as liver and muscle. The centers of the 14 lesions are coplanar, and eight alignment devices surround them facilitating superposition of the scan plane and the plane containing the centers of the lesions. Illustrative images made with a 1.5-T system are shown. All simulated lesions are detectable in T2-weighted head coil images. Corresponding T1-weighted images are also shown, the 2- and 3-mm lesions of set #2 and the 2-mm lesion of set #1 not being detectable. The phantoms could be useful for performance or acceptance testing and perhaps for quality assurance testing.

  3. Lesion Detection in CT Images Using Deep Learning Semantic Segmentation Technique

    NASA Astrophysics Data System (ADS)

    Kalinovsky, A.; Liauchuk, V.; Tarasau, A.

    2017-05-01

    In this paper, the problem of automatic detection of tuberculosis lesion on 3D lung CT images is considered as a benchmark for testing out algorithms based on a modern concept of Deep Learning. For training and testing of the algorithms a domestic dataset of 338 3D CT scans of tuberculosis patients with manually labelled lesions was used. The algorithms which are based on using Deep Convolutional Networks were implemented and applied in three different ways including slice-wise lesion detection in 2D images using semantic segmentation, slice-wise lesion detection in 2D images using sliding window technique as well as straightforward detection of lesions via semantic segmentation in whole 3D CT scans. The algorithms demonstrate superior performance compared to algorithms based on conventional image analysis methods.

  4. Effective detection of bronchial preinvasive lesions by a new autofluorescence imaging bronchovideoscope system.

    PubMed

    Chiyo, Masako; Shibuya, Kiyoshi; Hoshino, Hidehisa; Yasufuku, Kazuhiro; Sekine, Yasuo; Iizasa, Toshihiko; Hiroshima, Kenzo; Fujisawa, Takehiko

    2005-06-01

    Autofluorescence bronchoscopy is an important tool for the early detection of preinvasive bronchial lesions. However, autofluorescence bronchoscopy has difficulty distinguishing between preinvasive lesions and other benign epithelial changes. A new autofluorescence imaging bronchovideoscope system (AFI) comprises three signals, including an autofluorescence (460-690 nm) on excitation blue light (395-445 nm) and two different bands of reflected light: G' (550 nm) and R' (610 nm). We hypothesized that color analyses of these three wave lengths would improve our ability to differentiate between inflammation and preinvasive lesions. In order to prove this hypothesis and to evaluate the efficacy of AFI for detecting preinvasive lesions, we conducted a prospective study. A total of 32 patients with suspected or known lung cancer were entered into this study. Conventional white light bronchovideoscopy (WLB) and light induced fluorescence endoscopy (LIFE) were performed prior to using AFI. WLB and LIFE detected 62 lesions, including lung cancers (n=2), squamous dysplasias (n=30), and bronchitis (n=30). By utilizing AFI, 24 dysplasias and 2 cancer lesions were magenta in color, while 25 bronchitis lesions were blue. The sensitivities of detecting dysplasia by LIFE and AFI were 96.7% and 80%, respectively. The specificity of AFI (83.3%) was significantly higher than that of LIFE (36.6%) (p=0.0005). We conclude that AFI appears to represent a significant advance in distinguishing preinvasive and malignant lesions from bronchitis or hyperplasia under circumstances where LIFE would identify these all as abnormal lesions.

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

    PubMed

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

    2015-01-01

    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). 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. 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). 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. © 2015 The Authors. Journal of Neuroimaging published by Wiley Periodicals, Inc. on behalf of American Society of Neuroimaging.

  6. 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

  7. How do kV and mAs affect CT lesion detection performance?

    NASA Astrophysics Data System (ADS)

    Huda, W.; Ogden, K. M.; Shah, K.; Jadoo, C.; Scalzetti, E. M.; Lavallee, R. L.; Roskopf, M. L.

    2007-03-01

    The purpose of this study was to investigate how output (mAs) and x-ray tube voltage (kV) affect lesion detection in CT imaging. An adult Rando phantom was scanned on a GE LightSpeed CT scanner at x-ray tube voltages from 80 to 140 kV, and outputs from 90 to 360 mAs. Axial images of the abdomen were reconstructed and viewed on a high quality monitor at a soft tissue display setting. We measured detection of 2.5 to 12.5 mm sized lesions using a 2 Alternate Forced Choice (2-AFC) experimental paradigm that determined lesion contrast (I) corresponding to a 92% accuracy (I 92%) of lesion detection. Plots of log(I 92%) versus log(lesion size) were all approximately linear. The slope of the contrast detail curve was ~ -1.0 at 90 mAs, close to the value predicted by the Rose model, but monotonically decreased with increasing mAs to a value of ~ -0.7 at 360 mAs. Increasing the x-ray tube output by a factor of four improved lesion detection by a factor of 1.9 for the smallest lesion (2.5 mm), close to the value predicted by the Rose model, but only by a factor of 1.2 for largest lesion (12.5 mm). Increasing the kV monotonically decreased the contrast detail slopes from -1.02 at 80 kV to -0.71 at 140 kV. Increasing the x-ray tube voltage from 80 to 140 kV improved lesion detection by a factor of 2.8 for the smallest lesion (2.5 mm), but only by a factor of 1.7 for largest lesion (12.5 mm). We conclude that: (i) quantum mottle is an important factor for low contrast lesion detection in images of anthropomorphic phantoms; (ii) x-ray tube voltage has a much greater influence on lesion detection performance than x-ray tube output; (iii) the Rose model only predicts CT lesion detection performance at low x-ray tube outputs (90 mAs) and for small lesions (2.5 mm).

  8. Evaluating the effects of white matter multiple sclerosis lesions on the volume estimation of 6 brain tissue segmentation methods.

    PubMed

    Valverde, S; Oliver, A; Díez, Y; Cabezas, M; Vilanova, J C; Ramió-Torrentà, L; Rovira, À; Lladó, X

    2015-06-01

    The accuracy of automatic tissue segmentation methods can be affected by the presence of hypointense white matter lesions during the tissue segmentation process. Our aim was to evaluate the impact of MS white matter lesions on the brain tissue measurements of 6 well-known segmentation techniques. These include straightforward techniques such as Artificial Neural Network and fuzzy C-means as well as more advanced techniques such as the Fuzzy And Noise Tolerant Adaptive Segmentation Method, fMRI of the Brain Automated Segmentation Tool, SPM5, and SPM8. Thirty T1-weighted images from patients with MS from 3 different scanners were segmented twice, first including white matter lesions and then masking the lesions before segmentation and relabeling as WM afterward. The differences in total tissue volume and tissue volume outside the lesion regions were computed between the images by using the 2 methodologies. Total gray matter volume was overestimated by all methods when lesion volume increased. The tissue volume outside the lesion regions was also affected by white matter lesions with differences up to 20 cm(3) on images with a high lesion load (≈50 cm(3)). SPM8 and Fuzzy And Noise Tolerant Adaptive Segmentation Method were the methods less influenced by white matter lesions, whereas the effect of white matter lesions was more prominent on fuzzy C-means and the fMRI of the Brain Automated Segmentation Tool. Although lesions were removed after segmentation to avoid their impact on tissue segmentation, the methods still overestimated GM tissue in most cases. This finding is especially relevant because on images with high lesion load, this bias will most likely distort actual tissue atrophy measurements. © 2015 by American Journal of Neuroradiology.

  9. Herpes simplex virus detection in oral mucosa lesions in patients undergoing oncologic therapy.

    PubMed

    Sepúlveda Tebache, Ester; Brethauer Meier, Ursula; Jiménez Moraga, Marco; Morales Figueroa, Rocío; Rojas Castro, Jaime; Le Fort Canales, Patricia

    2003-01-01

    The presence of Herpes Simplex Virus (HSV) has been a frequent detection in gingivitis and ulcerations of oral mucosa in patients undergoing oncologic therapy. In these patients, lesions tend to show atypical clinical patterns, leading to misdiagnosis. To detect HSV, using an ELISA test, in oral lesions of patients under oncologic therapy, to determine localization of these lesions in the oral cavity, to relate their presence with the general diagnosis of the patient and to compare the test results with the previous clinical diagnosis of the lesions. Thirty lesions where examined in nineteen pediatric patients under oncologic therapy. Direct samples of all lesions were taken and an ELISA test for HSV type I and II was applied to them. General diagnosis of the patients was consigned, as well as localization of the lesions in the oral cavity and clinical diagnosis of them. A database was elaborated with all the information. 33% of lesions were positive to the test, most of them in patients with acute myeloid leukemia. Localization of lesions was not restricted to areas of mucosa attached to periosteum, but also in areas like the dorsum of the tongue. Positive predictivity of clinical diagnosis was 56,25% and negative predictive index was 92,86%. Sensitivity of the test was 90% and specificity was 65%. It is very important to corroborate clinical diagnosis of gingivitis and ulcerative lesions of the oral cavity of patients under oncologic therapy with laboratory tests, because of the atypical clinical presentation that can lead to misdiagnosis.

  10. Dual-temporal resolution dynamic contrast-enhanced MRI protocol for blood-brain barrier permeability measurement in enhancing multiple sclerosis lesions.

    PubMed

    Jelescu, I O; Leppert, I R; Narayanan, S; Araújo, D; Arnold, D L; Pike, G B

    2011-06-01

    To design a more accurate and reproducible technique for the measurement of blood-brain barrier (BBB) permeability in gadolinium-enhancing multiple sclerosis (MS) lesions. Four MS patients were scanned using a new dynamic contrast-enhanced (DCE)-magnetic resonance imaging (MRI) protocol based on an uninterrupted two-part acquisition consisting of an initial part at high temporal and low spatial resolutions and a second part at low temporal and high spatial resolutions. The method preserves both the high spatial resolution needed for the often small size of lesions and the high temporal resolution required during the first minute after injection to sufficiently sample the first-pass bolus. Simulations compared the performance of this new protocol with the conventional one at low temporal and high spatial resolutions throughout. The BBB permeability estimates changed by up to 33% between the two protocols. The new protocol led to simulated error on K(trans) of 7%-10%, versus 7%-30% with the conventional protocol, and was more robust with respect to offsets between acquisition and injection start times, differences in shape of the first-pass peak, and permeability values. The dual-temporal resolution protocol produces improved BBB permeability estimates and provides a more complete view of active inflammatory MS lesion pathology. Copyright © 2011 Wiley-Liss, Inc.

  11. 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

  12. Lesion-to-ventricle distance and other risk factors for the persistence of newly formed black holes in relapsing-remitting multiple sclerosis.

    PubMed

    Papadopoulou, Athina; Menegola, Milena; Kuhle, Jens; Ramagopalan, Sreeram V; D'Souza, Marcus; Sprenger, Till; Radue, Ernst-Wilhelm; Kappos, Ludwig; Yaldizli, Özgür

    2014-03-01

    Progenitor cells from the subventricular zone (SVZ) of the lateral ventricles are assumed to contribute to remyelination and resolution of black holes (BHs) in multiple sclerosis (MS). This process may depend on the distance between the lesion and the SVZ. The objective of this paper is to investigate the relationship between lesion-to-ventricle (LV) distance and persistence of new BHs. We analysed the magnetic resonance images (MRIs) of 289 relapsing-remitting (RR) MS patients, obtained during a multi-centre, placebo-controlled phase II trial over one year. Overall, 112/289 patients showed 367 new BHs at the beginning of the trial. Of these, 225 were located in 94/112 patients at the level of the lateral ventricles on axial MRIs and included in this analysis. In total, 86/225 (38%) BHs persisted at month 12. LV distance in persistent BHs (PBHs) was not longer than in transient BHs. In fact PBHs tended to be closer to the SVZ than transient BHs. A generalised linear mixed multivariate model adjusted for BHs clustered within a patient and including patient- as well as lesion-specific factors revealed size, ring contrast enhancement, and shorter LV distance as independent predictors for BH persistence. Location of BHs close to the lateral ventricles does not appear to favourably influence the resolution of new BHs in RRMS.

  13. Glomerular lesions in mice transgenic for growth hormone and insulinlike growth factor-I. I. Relationship between increased glomerular size and mesangial sclerosis.

    PubMed Central

    Doi, T.; Striker, L. J.; Gibson, C. C.; Agodoa, L. Y.; Brinster, R. L.; Striker, G. E.

    1990-01-01

    The glomeruli of mice transgenic for bovine growth hormone (GH mice) were disproportionately enlarged as a function of either kidney or body weight. Glomerular size correlated with mesangial sclerosis and the urine albumin/creatinine ratio. The glomerular lesions consisted of mesangial proliferation (4 to 5 weeks) followed by progressive mesangial sclerosis (19 weeks), resulting in complete glomerulosclerosis at 30 to 37 weeks. Albuminuria paralleled the glomerulosclerosis. In contrast, mice transgenic for insulinlike growth factor-I (IGF-I mice) did not develop glomerulosclerosis, even though glomerular size significantly increased. Glomerular hypertrophy, however, did not reach that in GH mice. These data suggest that high levels of circulating GH lead to a disproportionate increase in glomerular cellularity and volume, as well as glomerulosclerosis. This does not appear to be the result of high levels of circulating IGF-I stimulated by GH, as the serum IGF-I level in GH mice was lower than that in IGF-I mice. Images Figure 1 Figure 2 Figure 3 Figure 8 PMID:2399934

  14. Bennett lesions in baseball players detected by magnetic resonance imaging: assessment of association factors.

    PubMed

    Park, Jin-Young; Noh, Young-Min; Chung, Seok-Won; Moon, Sung-Gyn; Ha, Dae-Ho; Lee, Ki-Sun; Chung, Seok Won

    2016-05-01

    The purpose of this study was to evaluate the characteristics of Bennett lesions in baseball players compared with those without a Bennett lesion and to identify other possible factors associated with Bennett lesions on magnetic resonance imaging (MRI). We investigated 388 male baseball players with a career >1 year. Demographic factors and a routine physical examination, including glenohumeral internal rotation difference, scapular dyskinesis, and various pathologic changes, were reviewed on MRI to identify relative factors for Bennett lesions. Of the 388 patients evaluated, 125 (32.2%) were diagnosed with Bennett lesions of the shoulder. No significant differences were observed between the groups in demographic factors, physical examination results, visual analog scale score, American Shoulder and Elbow Surgeons score, or prevalence of concomitant diseases. However, players with Bennett lesions had played baseball longer than those without the lesions (P < .001). An association was found between Bennett lesions and the length of time that a patient with a Bennett lesion had played baseball. The prevalence of pathologic lesions detected on MRI and the physical examination results were not different between players with and without Bennett lesions. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  15. An in vitro comparison of detection methods for approximal carious lesions in primary molars.

    PubMed

    Chawla, N; Messer, L B; Adams, G G; Manton, D J

    2012-01-01

    This study aimed to compare and contrast in vitro six methods to determine the most accurate method for detecting approximal carious lesions in primary molars. Extracted primary molars (n = 140) were stored in 0.02% chlorhexidine solution and mounted in light-cured resin in pairs. The six carious lesion detection methods used by the three examiners to assess approximal carious lesions were visual inspection, digital radiography, two transillumination lights (SDI and NSK), and two laser fluorescence instruments (CDD and DDP). Five damaged teeth were discarded. The teeth (n = 135) were sectioned, serially ground, and examined under light microscopy using Downer's histological (HST) criteria as the gold standard. Intra- and inter-examiner reliability, agreement with HST, specificity, sensitivity, receiver operating characteristic (ROC) curves, and areas under the curve were calculated. This study found visual inspection to be the most accurate method when validated by histology. Transillumination with NSK light had the highest specificity, and digital radiography had the highest sensitivity for detecting enamel and/or dentinal carious lesions. Combining specificity and sensitivity into the area under ROC curves, enamel plus dentinal lesions were detected most accurately by visual inspection followed by digital radiography; dentinal lesions were detected most accurately by digital radiography followed by visual inspection. None of the four newly developed methods can be recommended as suitable replacements for visual inspection and digital radiography in detecting carious lesions on approximal surfaces of primary molars, and further developmental work is needed. Copyright © 2012 S. Karger AG, Basel.

  16. 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.

  17. Diagnostic accuracy of noncontrast MRI for detection of glenohumeral cartilage lesions: a prospective comparison to arthroscopy.

    PubMed

    VanBeek, Corinne; Loeffler, Bryan J; Narzikul, Alexa; Gordon, Victoria; Rasiej, Michael J; Kazam, Jonathan K; Abboud, Joseph A

    2014-07-01

    The purpose of this study was to determine the prevalence of glenohumeral articular cartilage lesions in patients with rotator cuff tendinopathy and to assess the accuracy of noncontrast magnetic resonance imaging (MRI) in detecting these defects compared with the "gold standard" of arthroscopy. Noncontrast MRI studies obtained in 84 consecutive patients undergoing shoulder arthroscopy for rotator cuff tendinopathy (mean age, 54.8 years; range, 17-82 years) were prospectively evaluated for glenohumeral cartilage lesions. Two fellowship-trained, experienced musculoskeletal radiologists were blinded from the arthroscopic findings and independently evaluated the glenoid and humeral head cartilage on 2 separate occasions. At arthroscopy, cartilage lesions of the humeral head were detected in 23 patients (frequency, 27.4%), and glenoid cartilage lesions were found in 20 patients (frequency, 23.8%). For detection of a humeral lesion on MRI, the radiologists' combined accuracy was 78%, sensitivity was 43%, and specificity was 91%. The combined accuracy for detection of glenoid lesions on MRI was 84%, sensitivity was 53%, and specificity was 93%. Combining the readers, low-grade lesions (International Cartilage Repair Society grades 1 and 2) of the glenoid and humerus were read as negative on MRI in 63% and 86% of cases, respectively. Overall accuracy of noncontrast MRI for detection of glenohumeral articular cartilage lesions is good; however, interpretation is reader dependent, and accuracy is significantly reduced for detection of low-grade lesions. On the basis of these findings, we recommend that patients with rotator cuff tendinopathy undergoing arthroscopy be informed that the presence and severity of cartilage lesions may be underestimated on MRI. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  18. 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

  19. Haemophilus ducreyi detection by polymerase chain reaction in oesophageal lesions of HIV patients.

    PubMed

    Borges, M C; Colares, J K B; Lima, D M; Fonseca, B A L

    2009-04-01

    HIV patients frequently have opportunistic oesophageal infections. We report Haemophilus ducreyi genetic material detected by polymerase chain reaction in biopsies of oesophageal lesions in three HIV-1-infected patients. This finding may be an indication of its aetiopathological role in oesophageal lesions of HIV patients.

  20. A prospective comparison of brain contrast characteristics and lesion detection using single-shot fast spin-echo and fast spin-echo.

    PubMed

    Mittal, T K; Halpin, S F; Bourne, M W; Hourihan, M D; Perkins, T; Sun, Y; Tan, S

    1999-07-01

    MRI is limited by movement artefact, even with current imagers, when examining a restless or claustrophobic patient. We prospectively analysed the images of 92 patients produced by a single-shot fast spin-echo (SSFSE) pulse sequence and compared them with conventional (FSE) and reduced-time fast spin-echo (RT-FSE) techniques, with regard to lesion detection and movement artefact in brain imaging. Images obtained in each case were independently reviewed and scored for overall diagnosis, number of lesions detected, and movement artefact. FSE showed 1217 lesions, RT-FSE 1137, and SSFSE 1044. This discrepancy arose mainly in patients with multiple sclerosis or small-vessel disease, since with SSFSE we were less able to separate small, adjacent low-contrast lesions than with FSE. Arbitrary movement scores were 36, 25 and zero respectively. There were, however, no clinically significant differences in overall diagnosis between the three techniques. SSFSE thus proved a reliable, fast, accurate method for obtaining T2-weighted images, and may be of particular use in the restless, claustrophobic or obtunded patient.

  1. 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.

  2. 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

  3. 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

  4. 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.

  5. Minimal intervention dentistry: part 4. Detection and diagnosis of initial caries lesions.

    PubMed

    Guerrieri, A; Gaucher, C; Bonte, E; Lasfargues, J J

    2012-12-01

    The detection of carious lesions is focused on the identification of early mineral changes to allow the demineralisation process to be managed by non-invasive interventions. The methods recommended for clinical diagnosis of initial carious lesions are discussed and illustrated. These include the early detection of lesions, evaluation of the extent of the lesion and its state of activity and the establishment of appropriate monitoring. The place of modern tools, including those based on fluorescence, is discussed. These can help inform patients. They are also potentially useful in regular control visits to monitor the progression or regression of early lesions. A rigorous and systematic approach to caries diagnosis is essential to establish a care plan for the disease and to identify preventive measures based on more precise diagnosis and to reduce reliance on restorative measures.

  6. Segmentation of Multiple Sclerosis Lesions in Brain MR Images Using Spatially Constrained Possibilistic Fuzzy C-Means Classification.

    PubMed

    Khotanlou, Hassan; Afrasiabi, Mahlagha

    2011-07-01

    This paper introduces a novel methodology for the segmentation of brain MS lesions in MRI volumes using a new clustering algorithm named SCPFCM. SCPFCM uses membership, typicality and spatial information to cluster each voxel. The proposed method relies on an initial segmentation of MS lesions in T1-w and T2-w images by applying SCPFCM algorithm, and the T1 image is then used as a mask and is compared with T2 image. The proposed method was applied to 10 clinical MRI datasets. The results obtained on different types of lesions have been evaluated by comparison with manual segmentations.

  7. Segmentation of Multiple Sclerosis Lesions in Brain MR Images Using Spatially Constrained Possibilistic Fuzzy C-Means Classification

    PubMed Central

    Khotanlou, Hassan; Afrasiabi, Mahlagha

    2011-01-01

    This paper introduces a novel methodology for the segmentation of brain MS lesions in MRI volumes using a new clustering algorithm named SCPFCM. SCPFCM uses membership, typicality and spatial information to cluster each voxel. The proposed method relies on an initial segmentation of MS lesions in T1-w and T2-w images by applying SCPFCM algorithm, and the T1 image is then used as a mask and is compared with T2 image. The proposed method was applied to 10 clinical MRI datasets. The results obtained on different types of lesions have been evaluated by comparison with manual segmentations. PMID:22606670

  8. Methods to detect antifibrillarin antibodies in patients with systemic sclerosis (SSc): a comparison.

    PubMed

    García, Josefina Huerta; Osuna, Monica Delgado; Castrejon, Filiberto Martinez; Enriquez, Laura Guzman; Reyes, Pedro A; Hermosillo, J Jesus Cortes

    2004-01-01

    Autoantibodies against nucleolar antigens are common in systemic sclerosis (SSc). They include autoantibodies against fibrillarin (Fb), which are serological markers for SSc. Fb is associated with the evolutionally-conserved box C/D of small nucleolar RNAs (snoRNAs). We compared indirect immunofluorescence (IIF), Western blot (WB), and immunoprecipitation (IPP) of total small RNAs assays to determine which of these techniques is most specific for the detection of snoRNPs. We also examined the frequency and specificity of autoantibodies from SSc patients to snoRNAs, snRNAs, and scRNAs, and concluded that 1) IIF can not determine autoantibody specificity against Fb, 2) 36% of SSc sera were false-negative by WB, and 3) by IPP, anti-Fb autoantibodies from SSc patients can bind U3, U8, U13, U15, and U22 snoRNAs.

  9. 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.

  10. 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

  11. Detection of Alveolar Fibrocytes in Idiopathic Pulmonary Fibrosis and Systemic Sclerosis

    PubMed Central

    Phin, Sophie; Debray, Marie-Pierre; Marchal-Somme, Joelle; Tiev, Kiet; Bonay, Marcel; Fabre, Aurélie; Soler, Paul; Dehoux, Monique; Crestani, Bruno

    2013-01-01

    Background Fibrocytes are circulating precursors for fibroblasts. Blood fibrocytes are increased in patients with idiopathic pulmonary fibrosis (IPF). The aim of this study was to determine whether alveolar fibrocytes are detected in broncho-alveolar lavage (BAL), to identify their prognostic value, and their potential association with culture of fibroblasts from BAL. Methods We quantified fibrocytes in BAL from 26 patients with IPF, 9 patients with Systemic Sclerosis(SSc)-interstitial lung disease (ILD), and 11 controls. BAL cells were cultured to isolate alveolar fibroblasts. Results Fibrocytes were detected in BAL in 14/26 IPF (54%) and 5/9 SSc patients (55%), and never in controls. Fibrocytes were in median 2.5% [0.4–19.7] and 3.0% [2.7–3.7] of BAL cells in IPF and SSc-ILD patients respectively. In IPF patients, the number of alveolar fibrocytes was correlated with the number of alveolar macrophages and was associated with a less severe disease but not with a better outcome. Fibroblasts were cultured from BAL in 12/26 IPF (46%), 5/9 SSc-ILD (65%) and never in controls. The detection of BAL fibrocytes did not predict a positive culture of fibroblasts. Conclusion Fibrocytes were detected in BAL fluid in about half of the patients with IPF and SSc-ILD. Their number was associated with less severe disease in IPF patients and did not associate with the capacity to grow fibroblasts from BAL fluid. PMID:23341987

  12. 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

  13. Coexistence of amyotrophic lateral sclerosis with neuro-Behçet's disease presenting as a longitudinally extensive spinal cord lesion: clinicopathologic features of an autopsied patient.

    PubMed

    Sato, Tomoe; Ouchi, Haruka; Shimbo, Junsuke; Sato, Aki; Yamazaki, Motoyoshi; Hashidate, Hideki; Igarashi, Shuichi; Kakita, Akiyoshi

    2014-04-01

    We report the clinical and autopsy features of a 65-year-old Japanese man who clinically exhibited overlap of both neuro-Behçet's disease (NBD) and amyotrophic lateral sclerosis (ALS). The patient had a HLA-B51 serotype, a recent history of uveitis and had suffered paraparesis, sensory and autonomic disturbance, frontal signs and tremor. A brain and spine MRI study revealed a longitudinally extensive thoracic cord (Th) lesion, but no apparent intracranial abnormalities. The lesion extended ventrally from Th4 to Th9, exhibiting low intensity on T1-weighted images, high intensity on T2-weighted and fluid-attenuated inversion recovery images and gadolinium enhancement. The patient's upper and lower motor neuron signs and sensory disturbance worsened and he died 16 months after admission. At autopsy, the spinal cord and brain exhibited characteristic histopathological features of both NBD and ALS, including chronic destruction of the ventral thoracic white and gray matter, perivascular lymphocytic infiltration, binucleated neurons, lower and upper motor neuron degeneration, Bunina bodies and skein-like inclusions. Although incidental coexistence of these rare disorders could occur in an individual, this case raises the possibility of a pathomechanistic association between NBD and ALS.

  14. 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.

  15. Detection of helicobacter pylori in benign laryngeal lesions by polymerase chain reaction: a cross sectional study

    PubMed Central

    2012-01-01

    Background Although Helicobacter Pylori (HP) was detected in some cases of chronic laryngitis, the results were not confirmed by polymerase chain reaction (PCR). By this time, it has not been found in laryngeal lesions by in house PCR, the most sensitive method for detecting the genome tracks. Regarding the previous results and also few numbers of studies about the presence of HP in benign laryngeal lesions, specifically by PCR, we aimed to investigate the presence of HP in benign laryngeal lesions by in-house PCR. Methods The samples were taken from 55 patients with benign laryngeal lesions and frozen in −20°C. One milliliter (ml) of lysis buffer was added to 100 mg (mg) of each sample and the tube was placed in 56°C overnight. Then DNA extraction was carried out. Results To find HP DNA, in-house PCR was performed that revealed 5 positive results among 55 patients with benign laryngeal lesions. Of them, 3 were polyp, 1 was nodule and 1 was papilloma. Conclusion Although the number of positive results was not a lot in this study, it was in contrast with previous studies which could not find any HP tracks in benign laryngeal lesions by other methods. More studies about the prevalence of HP in benign laryngeal lesions improve judging about the effect of this infection on benign laryngeal lesions. PMID:22515206

  16. KRAS and BRAF mutations and MSI status in precursor lesions of colorectal cancer detected by colonoscopy.

    PubMed

    Yamane, L S; Scapulatempo-Neto, C; Alvarenga, L; Oliveira, C Z; Berardinelli, G N; Almodova, E; Cunha, T R; Fava, G; Colaiacovo, W; Melani, A; Fregnani, J H; Reis, R M; Guimarães, D P

    2014-10-01

    Colorectal cancer (CRC) is one of the most frequent cancers worldwide. Adenoma is the main precursor lesion and, recently, the serrated polyps were described as a group of colorectal lesions with malignant potential. The morphologic and biologic characterizations of serrated polyps remain limited. The aim of the present study was to determine the frequency of KRAS and BRAF mutations and microsatellite instability (MSI) in CRC precursor lesions, to evaluate the association between molecular, pathologic and morphologic alterations in precursor lesions and to compare with the alterations detected in CRC. A series of 342 precursor lesions were removed from 155 patients during colonoscopy. After morphologic classification, molecular analysis was performed in 103 precursor lesions, and their genetic profile compared with 47 sporadic CRCs. Adenomas were the main precursor lesions (70.2%). Among the serrated polyps, the main precursor lesion was hyperplastic polyps (HPs) (82.4%), followed by sessile serrated adenomas (12.7%) and traditional serrated adenomas (2.0%). KRAS mutations were detected in 13.6% of the precursor lesions, namely in adenomas and in HPs, but in no serrated adenoma. BRAF mutations were found in 9 (8.7%) precursor lesions, mainly associated with serrated polyps and absent in adenomas (P<0.001). High MSI (MSI-H) was absent in precursor lesions. In the 47 CCR cases, 46.8% exhibited KRAS mutation, 6.5% BRAF mutations and 10.6% MSI-H. This study confirms the role of KRAS and BRAF mutations in CRC carcinogenesis, a crucial step in implementing CRC screening strategies.

  17. Automated detection of colorectal lesions with dual-energy CT colonography

    NASA Astrophysics Data System (ADS)

    Näppi, Janne J.; Kim, Se Hyung; Yoshida, Hiroyuki

    2012-03-01

    Conventional single-energy computed tomography colonography (CTC) tends to miss polyps 6 - 9 mm in size and flat lesions. Dual-energy CTC (DE-CTC) provides more complete information about the chemical composition of tissue than does conventional CTC. We developed an automated computer-aided detection (CAD) scheme for detecting colorectal lesions in which dual-energy features were used to identify different bowel materials and their partial-volume artifacts. Based on these features, the dual-energy CAD (DE-CAD) scheme extracted the region of colon by use of a lumen-tracking method, detected lesions by use of volumetric shape features, and reduced false positives by use of a statistical classifier. For validation, 20 patients were prepared for DE-CTC by use of reduced bowel cleansing and orally administered fecal tagging with iodine and/or barium. The DE-CTC was performed in dual positions by use of a dual-energy CT scanner (SOMATOM Definition, Siemens) at 140 kVp and 80 kVp energy levels. The lesions identified by subsequent same-day colonoscopy were correlated with the DE-CTC data. The detection accuracies of the DE-CAD and conventional CAD schemes were compared by use of leave-one-patient-out evaluation and a bootstrap analysis. There were 25 colonoscopy-confirmed lesions: 22 were 6 - 9 mm and 3 were flat lesions >=10 mm in size. The DE-CAD scheme detected the large flat lesions and 95% of the 6 - 9 mm lesions with 9.9 false positives per patient. The improvement in detection accuracy by the DE-CAD was statistically significant.

  18. Dual-energy computed tomography for the detection of focal liver lesions.

    PubMed

    Lago, K N; Vallejos, J; Capuñay, C; Salas, E; Reynoso, E; Carpio, J B; Carrascosa, P M

    To qualitatively and quantitatively explore the spectral study of focal liver lesions, comparing it with the usual polychromatic assessment with single-energy computed tomography. We prospectively studied 50 patients with at least one focal liver lesion who were referred for abdominal multidetector computed tomography with intravenous contrast material. The portal phase was acquired with dual energy sources. The density of the lesions and of the surrounding liver parenchyma was measured both in the baseline polychromatic acquisition and in the posterior monochromatic reconstructions at 40 keV, 70 keV, and 140 keV. Spectral curves were traced and the dual-energy indices and contrast-to-noise ratio were calculated. Lastly, the quality of the images and the detectability of the lesions were assessed qualitatively. Densitometric differences between the different types of lesions (avascular and vascularized) and the liver were greater at low energy levels (left side of the spectral curve) than in the polychromatic evaluation. In the subjective assessment, the 40keV energy level had the greatest lesion detectability. Monochromatic spectral study with dual-energy computed tomography provides better lesion detectability at 40keV compared to that provided by the ordinary polychromatic evaluation. Copyright © 2017 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

  19. Automatic detection of significant and subtle arterial lesions from coronary CT angiography

    NASA Astrophysics Data System (ADS)

    Kang, Dongwoo; Slomka, Piotr; Nakazato, Ryo; Cheng, Victor Y.; Min, James K.; Li, Debiao; Berman, Daniel S.; Kuo, C.-C. Jay; Dey, Damini

    2012-02-01

    Visual analysis of three-dimensional (3D) Coronary Computed Tomography Angiography (CCTA) remains challenging due to large number of image slices and tortuous character of the vessels. We aimed to develop an accurate, automated algorithm for detection of significant and subtle coronary artery lesions compared to expert interpretation. Our knowledge-based automated algorithm consists of centerline extraction which also classifies 3 main coronary arteries and small branches in each main coronary artery, vessel linearization, lumen segmentation with scan-specific lumen attenuation ranges, and lesion location detection. Presence and location of lesions are identified using a multi-pass algorithm which considers expected or "normal" vessel tapering and luminal stenosis from the segmented vessel. Expected luminal diameter is derived from the scan by automated piecewise least squares line fitting over proximal and mid segments (67%) of the coronary artery, considering small branch locations. We applied this algorithm to 21 CCTA patient datasets, acquired with dual-source CT, where 7 datasets had 17 lesions with stenosis greater than or equal to 25%. The reference standard was provided by visual and quantitative identification of lesions with any >=25% stenosis by an experienced expert reader. Our algorithm identified 16 out of the 17 lesions confirmed by the expert. There were 16 additional lesions detected (average 0.13/segment); 6 out of 16 of these were actual lesions with <25% stenosis. On persegment basis, sensitivity was 94%, specificity was 86% and accuracy was 87%. Our algorithm shows promising results in the high sensitivity detection and localization of significant and subtle CCTA arterial lesions.

  20. Screening Instruments for the Early Detection of Cognitive Impairment in Patients with Multiple Sclerosis

    PubMed Central

    Zemon, Vance; Rath, Joseph F.; Picone, MaryAnn; Gromisch, Elizabeth S.; Glubo, Heather; Smith-Wexler, Lucia; Foley, Frederick W.

    2017-01-01

    Background: Cognitive impairments are common in individuals with MS and adversely affect functioning. Early detection of cognitive impairment, therefore, would enable earlier, and possibly more effective, treatment. We sought to compare self-reports with a short neuropsychological test as possible screening tools for cognitive impairment. Methods: One hundred patients with MS were tested with the Minimal Assessment of Cognitive Function in Multiple Sclerosis; z scores were used to derive the Cognitive Index (CI). Receiver operator characteristic curve analyses were performed, with criteria for impairment set at −1.5 and −2.0 SD below the mean. Scores from two self-reports (the Multiple Sclerosis Neuropsychological Screening Questionnaire–Patient Version and the Behavior Rating Inventory of Executive Function–Adult Version [BRIEF-A]) and a neuropsychological test (the Symbol Digit Modalities Test [SDMT]) were entered as test variables. Exploratory regression analyses were conducted with 1) CI and self-reports and 2) CI and the Problem-Solving Inventory (PSI). Results: Classification accuracy was high or moderately high for SDMT when the criterion was −2.0 or −1.5 SD, respectively, but low for the self-reports. Hierarchical linear regression showed that the SDMT alone was the best predictor of cognitive impairment; adding the self-reports did not improve the model. Exploratory analyses indicated that certain self-reports (BRIEF-A, PSI) provided some explanatory power in separate models. Conclusions: The SDMT is a more accurate screening tool for cognitive impairment; however, self-reports provide additional information and may complement objective testing. Results suggest that screening for cognitive impairment may require a multidimensional approach. PMID:28243180

  1. Oligodendrogenesis and neurogenesis in remyelination in the cuprizone model of multiple sclerosis: correlation with the degree of lesion

    NASA Astrophysics Data System (ADS)

    Pishchelko, A.; Khodanovich, M.; Pan, E.; Glazacheva, V.; Akulov, A.; Yarnykh, V.

    2017-08-01

    In this research, a cuprizone model of multiple sclerosis (MS) was used to study oligodendrogenesis and neurogenesis in remyelination. It has been shown that, with the administration of cuprizone, the amount of myelin in a number of structures of white and gray matter and the level of neurogenesis decrease, while the level of oligodendrogenesis increases. The withdrawal of cuprizone leads to the restoration of myelin content, the reduction of the excessive production of oligodendrocytes and to the restoration of the number of neurons to control values. The negative correlation between the number of oligodendrocyte precursors (OPCs) and the degree of demyelination of the corpus callosum indicates migration of OLG precursors from the subventricular zone (SVZ) to the structure during demyelination.

  2. 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.

  3. Detection of lesions in dysplastic Barrett's esophagus by community and expert endoscopists.

    PubMed

    Schölvinck, Dirk W; van der Meulen, Kim; Bergman, Jacques J G H M; Weusten, Bas L A M

    2017-02-01

    Background and aims Endoscopic treatment of Barrett's esophagus (BE) consists of endoscopic resection of visible lesions followed by radiofrequency ablation (RFA) for any remaining flat BE. Because RFA is only justified in flat BE, detection of neoplastic lesions (high grade dysplasia [HGD] and early adenocarcinoma [EAC]) is crucial. We hypothesized that the detection of visible lesions containing HGD or EAC would be superior in BE expert centers compared with community hospitals, thereby supporting centralization of therapy for BE-related neoplasia. Methods Patients referred with histologically proven HGD or EAC to two Dutch BE expert centers were included. Referral letters, and endoscopy and pathology reports were reviewed for the description of the BE, presence of lesions, and histopathological analysis of target and random tissue sampling. Primary outcome was the endoscopic detection rate of lesions containing histopathologically proven neoplasia (HGD and/or EAC) in community and expert centers. Results There were 198 patients referred from 37 community hospitals (median referral time 55 days [interquartile range 33 - 85]). Detection rates for visible lesions were 60 % in community centers (75 % in patients with a biopsy diagnosis of EAC, 47 % in HGD) and 87 % in expert centers (98 % in EAC, 75 % in HGD); P < 0.001. Even with HGD/EAC on random biopsies from the index endoscopy, the yield at repeat endoscopy was < 50 % in community hospitals. In 79 patients referred solely because of random biopsy results, a lesion requiring endoscopic resection or surgery was found in 76 % by the expert endoscopists. Conclusions Endoscopists at community hospitals detect neoplastic lesions at a significantly lower rate. These data support the value of BE expert centers for work-up and further treatment of BE.

  4. 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.

  5. 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.

  6. 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.

  7. Simulations of lesion detection using a combined phased array LHMI-technique.

    PubMed

    Heikkilä, Janne; Hynynen, Kullervo

    2008-11-01

    Ultrasound based elasticity imaging techniques have been developed during the past decades. Some of these techniques are based on an internal radiation force stimulation in which a transient or dynamic radiation force is produced by using a single or dual-frequency sonication. In addition, sonication and data acquisition can be implemented using combined or separate transducers. In this simulation study of lesion detection using localized harmonic motion imaging (LHMI), we used a combined phased array designed for simultaneous thermal ablation and lesion detection. In the sonication mode, a focused single-frequency amplitude-modulated sonication is used to induce harmonic motion and in the tracking mode, some of the array elements are used for pulse-echo tracking of the induced displacements. The results showed that the size of the lesion affected the induced displacement around the sonication point. The displacement tracking simulations demonstrated that these changes in the displacement distributions can be detected using only a few of the array elements in the tracking mode but the exact size of the lesion can not be detected accurately. The simulations also showed that two lesions having the radius of 2.5mm can be distinguished if distance between these lesions is at least 2.5mm.

  8. Long-term deficits in motion detection thresholds and spike count variability after unilateral vestibular lesion

    PubMed Central

    Yu, Xiong-Jie; Thomassen, Jakob S.; Dickman, J. David; Newlands, Shawn D.

    2014-01-01

    The vestibular system operates in a push-pull fashion using signals from both labyrinths and an intricate bilateral organization. Unilateral vestibular lesions cause well-characterized motor deficits that are partially compensated over time and whose neural correlates have been traced in the mean response modulation of vestibular nuclei cells. Here we compare both response gains and neural detection thresholds of vestibular nuclei and semicircular canal afferent neurons in intact vs. unilateral-lesioned macaques using three-dimensional rotation and translation stimuli. We found increased stimulus-driven spike count variability and detection thresholds in semicircular canal afferents, although mean responses were unchanged, after contralateral labyrinth lesion. Analysis of trial-by-trial spike count correlations of a limited number of simultaneously recorded pairs of canal afferents suggests increased noise correlations after lesion. In addition, we also found persistent, chronic deficits in rotation detection thresholds of vestibular nuclei neurons, which were larger in the ipsilesional than the contralesional brain stem. These deficits, which persisted several months after lesion, were due to lower rotational response gains, whereas spike count variability was similar in intact and lesioned animals. In contrast to persistent deficits in rotation threshold, translation detection thresholds were not different from those in intact animals. These findings suggest that, after compensation, a single labyrinth is sufficient to recover motion sensitivity and normal thresholds for the otolith, but not the semicircular canal, system. PMID:24848470

  9. Experimental evaluation of a simple lesion detection task with time-of-flight PET

    NASA Astrophysics Data System (ADS)

    Surti, S.; Karp, J. S.

    2009-01-01

    A new generation of high-performance, time-of-flight (TOF) PET scanners have recently been developed. In earlier works, the gain with TOF information was derived as a reduction of noise in the reconstructed image, or essentially a gain in scanner sensitivity. These derivations were applicable to analytical reconstruction techniques and 2D PET imaging. In this work, we evaluate the gain measured in the clinically relevant task of lesion detection with TOF information in fully 3D PET scanners using iterative reconstruction algorithms. We performed measurements in a fully 3D TOF PET scanner using spherical lesions in uniform, cylindrical phantom. Lesion detectability was estimated for 10 mm diameter lesions using a non-prewhitening matched filter signal-to-noise-ratio (NPW SNR) as the metric. Our results show that the use of TOF information leads to increased lesion detectability, which is achieved with less number of iterations of the reconstruction algorithm. These phantom results indicate that clinically, TOF PET will allow reduced scan times and improved lesion detectability, especially in large patients.

  10. 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.

  11. 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. © 2015 John Wiley & Sons Ltd.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. Incidentally detected breast lesions on chest CT with US correlation: a pictorial essay

    PubMed Central

    Son, Jung Hee; Jung, Hyun Kyung; Song, Jong Woon; Baek, Hye Jin; Doo, Kyung Won; Kim, Woogyeong; Kim, Yeon Mee; Kim, Woon Won; Lee, Jung Sun; Cho, Een Young

    2016-01-01

    With the increasing use of computed tomography (CT), incidental breast lesions are detected more frequently. When interpreting chest CT findings, it is important for radiologists to carefully review the breast to recognize any abnormal findings that could affect patient management. The purpose of this study is to discuss incidental breast lesions on chest CT with ultrasonography correlation that may be encountered in routine clinical practice. PMID:27707680

  17. 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

  18. 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

  19. 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.

  20. Quantitative assessment of lesion detection accuracy, resolution, and reconstruction algorithms in neutron stimulated emission computed tomography.

    PubMed

    Lakshmanan, Manu N; Kapadia, Anuj J

    2012-07-01

    We present a quantitative analysis of the image quality obtained using filtered back-projection (FBP) with Ram-Lak filtering and maximum likelihood-expectation maximization (ML-EM)-with no post-reconstruction filtering in either case-in neutron stimulated emission computed tomography (NSECT) imaging using Monte Carlo simulations in the context of clinically relevant models of liver iron overload. The ratios of pixel intensities for several regions of interest and lesion shape detection using an active-contours segmentation algorithm are assessed for accuracy across different scanning configurations and reconstruction algorithms. The modulation transfer functions (MTFs) are also computed for the cases under study and are applied to determine a minimum detectable lesion spacing as a form of sensitivity analysis. The accuracy of NSECT imaging in measuring relative tissue concentration is presented for simulated clinical liver cases. When using the 15th iteration, ML-EM provides at least 25% better resolution than FBP and proves to be highly robust under low-signal high-noise conditions prevalent in NSECT. However, FBP gives more accurate lesion pixel intensity ratios and size estimates in some cases; due to advantages provided by both reconstruction algorithms, it is worth exploring the development of an algorithm that is a hybrid of the two. We also show that NSECT imaging can be used to accurately detect 3-cm lesions in backgrounds that are a significant fraction (one-quarter) of the concentration of the lesion, down to a 4-cm spacing between lesions.

  1. Effect of Cortical Bone Thickness on Detection of Intraosseous Lesions by Ultrasonography

    PubMed Central

    Adibi, Sadaf; Shakibafard, Alireza; Karimi Sarvestani, Zohreh; Saadat, Najmeh; Khojastepour, Leila

    2015-01-01

    Background. Usefulness of ultrasound (US) in detection of intrabony lesions has been showed. A cortical bone perforation or a very thin and intact cortical bone is prerequisite for this purpose. Objective. The current in vitro study was aimed at measuring the cut-off thickness of the overlying cortical bone which allows ultrasonic assessment of bony defects. Materials and Methods. 20 bovine scapula blocks were obtained. Samples were numbered from 1 to 20. In each sample, 5 artificial lesions were made. The lesions were made in order to increase the overlying bone thickness, from 0.1 mm in the first sample to 2 mm in the last one (with 0.1 mm interval). After that, the samples underwent ultrasound examinations by two practicing radiologists. Results. All five lesions in samples numbered 1 to 11 were detected as hypoechoic area. Cortical bone thickness more than 1.1 mm resulted in a failure in the detection of central lesions. Conclusion. We can conclude that neither bony perforation nor very thin cortical bones are needed to consider US to be an effective imaging technique in the evaluation of bony lesion. PMID:26366296

  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. Exosomal proteome analysis of cerebrospinal fluid detects biosignatures of neuromyelitis optica and multiple sclerosis.

    PubMed

    Lee, Jingyun; McKinney, Kimberly Q; Pavlopoulos, Antonis J; Han, May H; Kim, Su-Hyun; Kim, Ho Jin; Hwang, Sunil

    2016-11-01

    Quantitative proteomic analysis of exosomes isolated from cerebrospinal fluid (CSF) of neuromyelitis optica (NMO) patients detected signature proteins differentiating NMO from multiple sclerosis (MS) and idiopathic longitudinally extensive transverse myelitis. Exosomes with good yields were obtained using ultracentrifugation from pooled CSF assisted by chemokine-based clustering strategy, which improved target molecule identification by providing amplified fold change values. 442 significant proteins generated a list of signature molecules of diseases validated primarily by the identification of known markers such as glial fibrillary acidic protein (GFAP) and fibronectin specific to NMO and MS respectively. MetaCore pathway analysis of significant proteins supported the involvement of these proteins in disease progression via neurological pathway. Expression levels of target molecules from orthogonal label-free quantification employing quadrupole-Orbitrap hybrid mass spectrometry were in good agreement with those from Western blotting. Additional investigation of GFAP and fibronectin as representative disease molecules revealed their presence in intact exosomes as detected by flow cytometry. This comprehensive study suggests that the exosomal proteomic analysis of CSF can be applied to the identification and characterization of inflammatory disorders of the central nervous system.

  4. Improving power to detect disease progression in multiple sclerosis through alternative analysis strategies.

    PubMed

    Healy, Brian; Chitnis, Tanuja; Engler, David

    2011-10-01

    In patients with multiple sclerosis, investigation of a treatment effect on disease progression in clinical trials and observational studies often uses sustained progression on the expanded disability status scale (EDSS) as an outcome. It is not clear whether this outcome is the most powerful to detect a treatment effect on clinical disease progression. Assessment of EDSS modeling choice on the detection of treatment effect was of interest. This assessment was separately conducted under three potential treatment effects: treatment reducing the chance of higher future EDSS, treatment increasing the chance of lower future EDSS, and treatment leading to both effects. To assess the effect of modeling choice, nine modeling strategies were applied to the data to determine the most powerful approach. EDSS measurements were simulated at 6 month intervals for 24 months. Each patient's initial EDSS value ranged between 0 and 3, and probabilities of transitioning from one EDSS state to another were based on the empirical probabilities of transition obtained from available clinical data. Modeling approaches based on sustained progression had less power than approaches which modeled the EDSS score directly, regardless of treatment effect. This difference was especially pronounced when the treatment effect corresponded to an increase in the probability of improvement. Sustained progression on the EDSS is a less powerful outcome measure for clinical progression than approaches based on the actual EDSS values.

  5. Model-Based Iterative Reconstruction Versus Adaptive Statistical Iterative Reconstruction and Filtered Back Projection in Liver 64-MDCT: Focal Lesion Detection, Lesion Conspicuity, and Image Noise

    PubMed Central

    Shuman, William P.; Green, Doug E.; Busey, Janet M.; Kolokythas, Orpheus; Mitsumori, Lee M.; Koprowicz, Kent M.; Thibault, Jean-Baptiste; Hsieh, Jiang; Alessio, Adam M.; Choi, Eunice; Kinahan, Paul E.

    2017-01-01

    OBJECTIVE The purpose of this study is to compare three CT image reconstruction algorithms for liver lesion detection and appearance, subjective lesion conspicuity, and measured noise. MATERIALS AND METHODS Thirty-six patients with known liver lesions were scanned with a routine clinical three-phase CT protocol using a weight-based noise index of 30 or 36. Image data from each phase were reconstructed with filtered back projection (FBP), adaptive statistical iterative reconstruction (ASIR), and model-based iterative reconstruction (MBIR). Randomized images were presented to two independent blinded reviewers to detect and categorize the appearance of lesions and to score lesion conspicuity. Lesion size, lesion density (in Hounsfield units), adjacent liver density (in Hounsfield units), and image noise were measured. Two different unblinded truth readers established the number, appearance, and location of lesions. RESULTS Fifty-one focal lesions were detected by truth readers. For blinded reviewers compared with truth readers, there was no difference for lesion detection among the reconstruction algorithms. Lesion appearance was statistically the same among the three reconstructions. Although one reviewer scored lesions as being more conspicuous with MBIR, the other scored them the same. There was significantly less background noise in air with MBIR (mean [± SD], 2.1 ± 1.4 HU) than with ASIR (8.9 ± 1.9 HU; p < 0.001) or FBP (10.6 ± 2.6 HU; p < 0.001). Mean lesion contrast-to-noise ratio was statistically significantly higher for MBIR (34.4 ± 29.1) than for ASIR (6.5 ± 4.9; p < 0.001) or FBP (6.3 ± 6.0; p < 0.001). CONCLUSION In routine-dose clinical CT of the liver, MBIR resulted in comparable lesion detection, lesion characterization, and subjective lesion conspicuity, but significantly lower background noise and higher contrast-to-noise ratio compared with ASIR or FBP. This finding suggests that further investigation of the use of MBIR to enable dose

  6. 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

  7. Confocal fluorescence microscopy for detection of cervical preneoplastic lesions

    NASA Astrophysics Data System (ADS)

    Sheikhzadeh, Fahime; Ward, Rabab K.; Carraro, Anita; Chen, Zhaoyang; van Niekerk, Dirk; MacAulay, Calum; Follen, Michele; Lane, Pierre; Guillaud, Martial

    2015-03-01

    We examined and established the potential of ex-vivo confocal fluorescence microscopy for differentiating between normal cervical tissue, low grade Cervical Intraepithelial Neoplasia (CIN1), and high grade CIN (CIN2 and CIN3). Our objectives were to i) use Quantitative Tissue Phenotype (QTP) analysis to quantify nuclear and cellular morphology and tissue architecture in confocal microscopic images of fresh cervical biopsies and ii) determine the accuracy of high grade CIN detection via confocal microscopy. Cervical biopsy specimens of colposcopically normal and abnormal tissues obtained from 15 patients were evaluated by confocal fluorescence microscopy. Confocal images were analyzed and about 200 morphological and architectural features were calculated at the nuclear, cellular, and tissue level. For the purpose of this study, we used four features to delineate disease grade including nuclear size, cell density, estimated nuclear-cytoplasmic (ENC) ratio, and the average of three nearest Delaunay neighbors distance (3NDND). Our preliminary results showed ENC ratio and 3NDND correlated well with histopathological diagnosis. The Spearman correlation coefficient between each of these two features and the histopathological diagnosis was higher than the correlation coefficient between colposcopic appearance and histopathological diagnosis. Sensitivity and specificity of ENC ratio for detecting high grade CIN were both equal to 100%. QTP analysis of fluorescence confocal images shows the potential to discriminate high grade CIN from low grade CIN and normal tissues. This approach could be used to help clinicians identify HGSILs in clinical settings.

  8. Brain MRI lesion load at 1.5T and 3T vs. clinical status in multiple sclerosis

    PubMed Central

    Stankiewicz, James M; Glanz, Bonnie I; Healy, Brian C; Arora, Ashish; Neema, Mohit; Benedict, Ralph HB; Guss, Zachary D; Tauhid, Shahamat; Buckle, Guy J; Houtchens, Maria K; Khoury, Samia; Weiner, Howard L; Guttmann, Charles RG; Bakshi, Rohit

    2010-01-01

    Background/Purpose To assess correlation between brain lesions and clinical status with 1.5T and 3T MRI. Methods Brain MRI fluid-attenuated inversion-recovery (FLAIR) sequences were performed in 32 MS patients Expanded Disability Status Scale (EDSS) score (mean +/− SD) 2 +/− 2.0 (range 0–8), disease duration 9.3 +/− 8.0 (range 0.8–29) years]. Results FLAIR lesion volume (FLLV) at 3T was higher than at 1.5T (p=0.01). Correlation between 1.5T FLLV and EDSS score was poor, while 3T FLAIR lesion volume correlated moderately and significantly (rs=0.39, p=0.03). When controlling for age and depression, correlations between FLLV and cognitive measures were significant at 1.5T for the Judgment of Line Orientation test (JLO) (rs =−0.44, p=0.05), the Symbol Digit Modalities Test (SDMT) (rs=−0.49, p=0.02) and the California Verbal Learning Test, delayed free recall (CVLT DR) (rs=−0.44, p=0.04). Correlations at 3T were also significant for these tests, but of greater magnitude: JLO (rs =−0.70, p=0.0005), SDMT (rs =−0.73, p=0.0001), CVLT DR (rs=−.061, p=0.003). Additional significant correlations obtained only at 3T included the two second paced auditory serial addition test (rs=−0.55, p=0.01), the Brief Visuospatial Memory Test-Delayed Free Recall (rs=−0.56, p=0.007), and the California Verbal Learning Test total recall (rs=−0.42, p=0.05). Conclusion MRI at 3T may boost sensitivity and improve validity in MS brain lesion assessment. PMID:19888926

  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. [Method of automatic detection of brain lesion based on wavelet feature vector].

    PubMed

    Fan, Ya; Liu, Wei; Feng, Huanqing

    2011-06-01

    A new method of automatic detection of brain lesion based on wavelet feature vector of CT images has been proposed in the present paper. Firstly, we created training samples by manually segmenting normal CT images into gray matter, white matter and cerebrospinal fluid sub images. Then, we obtained the cluster centers using FCM clustering algorithm. When detecting lesions, the CT images to be detected was automatically segmented into sub images, with a certain degree of over-segmenting allowed under the premise of ensuring accuracy as much as possible. Then we extended these sub images and extracted the features to compute the distances with the cluster centers and to determine whether they belonged to the three kinds of normal samples, or, otherwise, belonged to lesions. The proposed method was verified by experiments.

  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. 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.

  13. Effect of patient thickness and scan duration on lesion detectability in PET oncology imaging

    NASA Astrophysics Data System (ADS)

    Cheng, Phillip M.; Kinahan, Paul E.; Comtat, Claude; Lartizien, Carole; Lewellen, Thomas K.

    2005-04-01

    A dominant component of image quality for whole-body positron emission tomography (PET) imaging is attenuation, which is determined by patient thickness. This can be partially compensated for by adjusting scan duration. We evaluate the effect of changes in patient thickness and scan duration on lesion detection with model observers. We simulated 2D PET acquisitions of an anthropomorphic phantom with spherical target lesions. Three different anthropomorphic phantoms were used, with effective abdominal diameters of 20 cm, 27 cm, and 35 cm. The diameters of the lesions were varied from 1.0 to 3.0 cm, and the contrast ratios of the lesions were varied from 1.5 to 4.0. Noise-free scans were simulated with an analytical simulator. Poisson noise was added to simulate scan durations ranging from 1 to 10 minutes per bed position, using noise equivalent count rates previously measured using a modified NEMA NU2 countrate phantom. The average detectability of each target lesion under each condition was calculated using a non-prewhitening matched filter from 25 noisy realizations for each combination of parameters. Our results demonstrate the variation of the minimum scan duration required to detect a target of a given size and contrast ratio, for any fixed threshold of detectability. For image quality to remain constant for patients with larger cross-sectional areas, acquisition times should be increased accordingly, although in some cases this may not be possible due to practical constraints.

  14. 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.

  15. Effects of grayscale window/level parameters on breast lesion detectability

    NASA Astrophysics Data System (ADS)

    Johnson, Jeffrey P.; Nafziger, John S.; Krupinski, Elizabeth A.; Lubin, Jeffrey; Roehrig, Hans

    2003-05-01

    The detectability of low-contrast lesions in medical images can be affected significantly by the choice of grayscale window width and level (W/L) for electronic display. Our objective was to measure the effects of various W/L conditions on lesion detectability in simulated and real mammographic images, and then correlate observer performance with predictions of detection thresholds derived from a visual discrimination model (VDM). In the first experiment, detection thresholds were measured in 2AFC trials for five W/L conditions applied to simulated mammographic backgrounds and lesions (i.e., Gaussian "masses" and blurred-disk "microcalcification clusters") using nonmedical observers. In the second experiment, the detectability of real microcalcification clusters in digitized mammograms was evaluated for three W/L conditions in an ROC observer study with mammographers. For the simulated images, there was generally good agreement between model and experimental thresholds and their variations across W/L conditions. Both experimental and model results showed significant reductions in thresholds when W/L processing was applied locally near the lesion. ROC results with digitized mammograms read by radiologists, however, failed to show enhanced detection of microcalcifications using a localized W/L frame, probably due to the nonuniform appearance of parenchymal tissue across the image.

  16. 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.

  17. 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.

  18. Detection of HPV-induced cervical (pre) neoplastic lesions: a tissue microarray (TMA) study.

    PubMed

    Arafa, Mohammad; Boniver, Jacques; Delvenne, Philippe

    2008-10-01

    The aim of this study was to evaluate the usefulness of a panel of biomarkers in the characterization of human papillomavirus (HPV)-induced cervical lesions. Management of these lesions depends on their histologic confirmation. Misinterpretation especially for benign mimics results in a significant diagnostic disagreement. For these reasons, a continuous effort is still needed to discover surrogate markers, which could support the final diagnosis. Archival biopsies of normal ectocervical and endocervical tissues, squamous metaplasia, cervical intraepithelial neoplasia (CIN), squamous cell carcinoma, adenocarcinoma in situ, and adenocarcinoma were retrieved to perform a tissue microarray (TMA). A panel of markers was tested on the TMA obtained slides by in situ hybridization (HPV DNA) and immunohistochemistry (p16, involucrin, Ki-67, and HPV L1 proteins). The sensitivity to detect high-risk HPV DNA increased with lesion's severity. In situ hybridization signals suggesting integrated viral physical status predominated in CIN II/III, squamous cell carcinoma, and glandular (pre) neoplastic lesions. The p16 and Ki-67 protein expression increased from CIN I to CIN III and to infiltrative lesions. Involucrin positivity was better appreciated in well-differentiated diagnostic entities (ectocervix, mature metaplasia, and CIN I). HPV L1 antibody detected the viral capsid protein in a low proportion of CIN I and II. In conclusion, using a panel of cervical biomarkers improves the final reporting of various HPV-induced epithelial lesions. Carefully constructed TMA with single spots of 1-mm diameter are powerful tools, which have a high reliability in representing full tissue sections.

  19. Distribution of the immune inhibitory molecules CD200 and CD200R in the normal central nervous system and multiple sclerosis lesions suggests neuron-glia and glia-glia interactions.

    PubMed

    Koning, Nathalie; Swaab, Dick F; Hoek, Robert M; Huitinga, Inge

    2009-02-01

    CD200 is a membrane glycoprotein that suppresses immune activity via its receptor, CD200R. CD200-CD200R interactions have recently been considered to contribute to the "immune privileged" status of the central nervous system (CNS). The mechanisms by which these interactions take place are not well understood in part because there is limited detailed information on the distribution of CD200 and CD200R in the CNS. Here, we used immunohistochemistry to characterize the distinct anatomical and cellular distribution of these molecules in multiple sclerosis (MS) lesions and controls. CD200 was robustly expressed in gray matter areas including the cerebral cortex, hippocampus, striatum, cerebellum, and spinal cord, where neurons appeared immunopositive. CD200 expression was also detected in oligodendrocytes, but not in astrocytes or microglia. In CNS samples from MS patients, CD200 expression was additionally observed on reactive astrocytes in chronic active plaque centers, despite our previous finding of an overall decrease ofCD200 expression in MS lesions. In contrast to CD200, the immunolocalization pattern of CD200R was very distinct, showing high expression on perivascular macrophages in both gray and white matter. Using flow cytometry, we also found that human primary microglia express low levels of CD200R. These data suggest that CD200-mediated immune suppression may occur not only via neuron-microglia interactions, but also via glia-glia interactions, especially in inflammatory conditions in which an immune-suppressive environment needs to be restored; this may occur as a result of increased CD200 expression on reactive astrocytes.

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

    PubMed Central

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

    2016-01-01

    Abstract. 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 6×2173 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

  1. 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

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

    PubMed

    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.

  3. Automated detection of spiculated lesions and architectural distortions in digitized mammograms

    NASA Astrophysics Data System (ADS)

    Zhang, Ming; Giger, Maryellen L.

    1995-05-01

    Mammographic stellate lesions and architectural distortions are usually associated with malignancy, which makes them important signs in the screening for breast cancer. This paper proposes a novel method for the automatic detection of these lesions with the use of a Hough spectrum based geometric texture analysis. The Hough spectrum technique is developed from the traditional Hough transform, which is effective in the description of geometric structures. The Hough spectrum inherits such an ability and extends it into texture analysis for the description of those texture features geometric in nature, such as the spicula of a stellate lesion. When applied in mammographic image processing, an ROI is first transformed into its Hough spectrum, and then thresholding is conducted with its threshold level based on the statistical properties of the spectrum. Those ROIs with strong signals of spiculation are then identified as regions of potential lesions. Our preliminary studies, using only the Hough spectrum based technique without further feature analyses to reduce false positive detection, have yielded sensitivities of 81% for spiculated masses and 67% for architectural distortions at false positive rates of 0.97 and 2.2 per image, respectively. This manifests clearly the potential of the developed technique in the detection of such types of mammographic lesions.

  4. Validity of MicroCT for in vitro detection of proximal carious lesions in primary molars.

    PubMed

    Soviero, V M; Leal, S C; Silva, R C; Azevedo, R B

    2012-01-01

    This study aimed to validate the MicroCT for detection of proximal carious lesions in primary molars, using histology as the gold standard. Forty-eight proximal surfaces of primary molars were examined. Two calibrated examiners conducted the examinations independently. Proximal surfaces were visually scored, using ICDAS. Bitewing radiographs, Micro-CT and histological analyses used caries scores: 0=sound; 1=outer enamel; 2=inner enamel; 3=not spread dentine; 4=outer dentine; 5=inner dentine. Axial and sagital images were used for Micro-CT analysis, whilst for histology, tooth sections (400μm) were analyzed stereomicroscopically (×15). Inter-examiner agreement ranged from 0.87 to 0.93 kappa coefficient (k). Histological analysis revealed a frequency of sound tooth surfaces (18.8%) enamel carious lesions (E1) (48%) and dentine carious lesions (D1) (33.3%). MicroCT showed high correlation with histology (r(s)0.88). At both diagnostic thresholds (E1 and D1), sensitivity and accuracy were higher for MicroCT. Inter-device agreement between MicroCT and histology was k=0.81. No difference was found between MicroCT and histology as gold standards for detecting carious lesions using ICDAS. MicroCT can be used as a gold standard for detecting carious lesions in proximal surfaces in primary molars. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Optimised nuclear medicine method for tumour marking and sentinel node detection in occult primary breast lesions.

    PubMed

    De Cicco, C; Trifirò, G; Intra, M; Marotta, G; Ciprian, A; Frasson, A; Prisco, G; Luini, A; Viale, G; Paganelli, G

    2004-03-01

    The aim of this study was to evaluate the feasibility of sentinel node (SN) biopsy in occult breast lesions with different radiopharmaceuticals and to establish the optimal lymphoscintigraphic method to detect both occult lesions and SNs (SNOLL: sentinel node and occult lesion localisation). Two hundred and twenty-seven consecutive patients suspected to have clinically occult breast carcinoma were enrolled in the study. In addition to the radioguided occult lesion localisation (ROLL) procedure, using macroaggregates of technetium-99m labelled human serum albumin (MAA) injected directly into the lesion, lymphoscintigraphy was performed with nanocolloids (NC) injected in a peritumoral (group I) or a subdermal site (group II). In group III, a sole injection of NC was done into the lesion in order to perform both ROLL and SNOLL. Overall, axillary SNs were identified in 205 of the 227 patients (90.3%). In 12/62 (19.4%) patients of group I and 9/79 (11.4%) patients of group III, radioactive nodes were not visualised, whereas SNs were successfully localised in 85 of 86 patients of group II ( P<0.001). Pathological findings revealed breast carcinoma in 148/227 patients (65.2%) and benign lesions in 79 (34.8%). A total of 131 axillary SNs were removed in 118 patients with breast carcinoma; intraoperative examination of the SNs revealed metastatic involvement in 16 out of 96 cases of invasive carcinoma (16.7%). It is concluded that the combination of the ROLL procedure with direct injection of MAA into the lesion and lymphoscintigraphy performed with subdermal injection of radiocolloids represents the method of choice for accurate localisation of both non-palpable lesions and SNs.

  6. 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.

  7. 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

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

    PubMed

    Lemon, James; Kockara, Sinan; Halic, Tansel; Mete, Mutlu

    2015-01-01

    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. 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. 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 addition, we tested

  9. Clinically and mammographically occult breast lesions: detection and classification with high-resolution sonography.

    PubMed

    Buchberger, W; Niehoff, A; Obrist, P; DeKoekkoek-Doll, P; Dünser, M

    2000-08-01

    With recent significant advances in ultrasound technology, the potential of high-resolution sonography to improve the sensitivity of cancer diagnosis in women with dense breasts has become a matter of interest for breast imagers. To determine how often physician-performed high-resolution sonography can detect nonpalpable breast cancers that are not revealed by mammography, 8,970 women with breast density grades 2 through 4 underwent high-resolution sonography as an adjunct to mammography. All sonographically detected, clinically and mammographically occult breast lesions that were not simple cysts were prospectively classified into benign, indeterminate, or malignant categories. Diagnoses were confirmed by ultrasound-guided fine-needle aspiration, core-needle biopsy, or surgical biopsy. In 8,103 women with normal findings at mammography and physical examination, 32 cancers and 330 benign lesions were detected in 273 patients with sonography only. Eight additional cancers were found in 867 patients with a malignant (n = 5) or a benign (n = 3) palpable or mammographically detected index lesion. The overall prevalence of cancers detected with screening sonography was 0.41%, and the proportion of sonographically detected cancers to the total number of nonpalpable cancers was 22%. The mean size of invasive cancers detected only by sonography was 9.1 mm, and was not statistically different from the mean size of invasive cancers detected by mammography. The sensitivity of prospective sonographic classification for malignancy was 100%, and the specificity was 31%. In conclusion, the use of high-resolution sonography as an adjunct to mammography in women with dense breasts may lead to detection of a significant number of otherwise occult cancers that are no different in size from nonpalpable mammographically detected cancers. Prospective classification of these lesions based on sonographic characteristics resulted in an acceptable benign-to-malignant biopsy rate of 6.3:1.

  10. Higher education moderates the effect of T2 lesion load and third ventricle width on cognition in multiple sclerosis.

    PubMed

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

    2014-01-01

    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. 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. 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. 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.

  11. 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.

  12. In vitro performance of different methods in detecting occlusal caries lesions.

    PubMed

    Gomez, J; Zakian, C; Salsone, S; Pinto, S C S; Taylor, A; Pretty, I A; Ellwood, R

    2013-02-01

    Early caries detection is essential for the implementation of preventive, therapeutic and intervention strategies within general dental practice. The aim of this study was to compare the in vitro performance of the International Caries Detection and Assessment System (ICDAS), digital photographs scored with ICDAS (ICDAS photographs), fibre-optic transillumination (FOTI), optical coherence tomography (OCT), SoproLife(®) camera and two implementations of quantitative light-induced fluorescence a commercial (QLF-Inspektor Research systems) and a custom (QLF-Custom) system, to detect early and intermediate occlusal lesions. One hundred and twelve permanent extracted teeth were selected and assessed with each detection method. Histological validation was used as a gold standard. The detection methods were compared by means of sensitivity, specificity, areas under receiver operating characteristic (AUROC) curves for enamel and dentine levels and with the Spearman's rank correlation coefficient against histology. For any enamel or dentine caries detection, the AUROC curves ranged from 0.86 (OCT) to 0.98 (ICDAS and ICDAS photographs, SoproLife(®) camera) and at the dentine level from 0.83 (OCT) to 0.96 for FOTI. The correlations with histology ranged between 0.65 (OCT) and 0.88 (ICDAS and FOTI). Under in vitro conditions, the assessed detection methods showed excellent intra-examiner reproducibility. All the methods were strongly correlated with histology (p<0.01) except OCT which showed a moderate correlation (0.65). Even though all methods present similar performance in detecting occlusal caries lesions, visual inspection seems to be sufficient to be used in clinical practice for detection and assessment of lesion depth. Other methods may be useful in monitoring caries lesion behaviour. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. 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.

  14. Computer-aided detection of early neoplastic lesions in Barrett's esophagus.

    PubMed

    van der Sommen, Fons; Zinger, Svitlana; Curvers, Wouter L; Bisschops, Raf; Pech, Oliver; Weusten, Bas L A M; Bergman, Jacques J G H M; de With, Peter H N; Schoon, Erik J

    2016-07-01

    Early neoplasia in Barrett's esophagus is difficult to detect and often overlooked during Barrett's surveillance. An automatic detection system could be beneficial, by assisting endoscopists with detection of early neoplastic lesions. The aim of this study was to assess the feasibility of a computer system to detect early neoplasia in Barrett's esophagus. Based on 100 images from 44 patients with Barrett's esophagus, a computer algorithm, which employed specific texture, color filters, and machine learning, was developed for the detection of early neoplastic lesions in Barrett's esophagus. The evaluation by one endoscopist, who extensively imaged and endoscopically removed all early neoplastic lesions and was not blinded to the histological outcome, was considered the gold standard. For external validation, four international experts in Barrett's neoplasia, who were blinded to the pathology results, reviewed all images. The system identified early neoplastic lesions on a per-image analysis with a sensitivity and specificity of 0.83. At the patient level, the system achieved a sensitivity and specificity of 0.86 and 0.87, respectively. A trade-off between the two performance metrics could be made by varying the percentage of training samples that showed neoplastic tissue. The automated computer algorithm developed in this study was able to identify early neoplastic lesions with reasonable accuracy, suggesting that automated detection of early neoplasia in Barrett's esophagus is feasible. Further research is required to improve the accuracy of the system and prepare it for real-time operation, before it can be applied in clinical practice. © Georg Thieme Verlag KG Stuttgart · New York.

  15. Detection of potassium channel KIR4.1 antibodies in Multiple Sclerosis patients.

    PubMed

    Marnetto, Fabiana; Valentino, Paola; Caldano, Marzia; Bertolotto, Antonio

    2017-06-01

    The presence of KIR4.1 antibodies has been proposed to be a characteristic of Multiple Sclerosis (MS). This could have a significant impact on disease management. However, the validation of the initial findings has failed till date. Conflicting results have been attributed to difficulties in isolating the lower-glycosylated (LG) KIR4.1 expressed in oligodendrocytes, the putative target antigen of autoantibodies. The aim of this study is to verify the presence of KIR4.1 antibodies in MS patients, by independently replicating the originally-described procedure. Assay procedure consisted of KIR4.1 expression in HEK293 cells, 3-step elution to isolate LG-KIR4.1 in elution fraction 3, and ELISA. Sera of 48 MS patients and 46 HCs were studied in 21 working sessions. In a preliminary analysis, we observed different KIR4.1 antibody levels between MS patients and Healthy Controls (HCs). However, a high variability across working sessions was observed and the sensitivity of the assay was very low. Thus, stringent criteria were established in order to identify working sessions in which the pure LG-KIR4.1 was isolated. As per these criteria, we detected LG-KIR4.1 antibodies in 28% of MS patients and 5% of HCs. Unlike previous findings, this study is in agreement with the original report. We propose further efforts be made towards the development of a uniform method to establish the detection of KIR4.1 antibodies in MS patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. [Contribution of cognitive evoked potentials for detecting early cognitive disorders in multiple sclerosis].

    PubMed

    Magnié, M N; Bensa, C; Laloux, L; Bertogliati, C; Faure, S; Lebrun, C

    2007-11-01

    In Multiple Sclerosis (MS), one of the most frequent neurological diseases in young adults, cognitive dysfunctions have been under considered whereas their evolution may produce a fronto-sous-cortical deterioration and more than half of the MS patients present such dysfunctions. Nevertheless sensory evoked-potentials are classically used in this disease, event-related potentials (ERP) are not included in the clinical exploration of MS. Two studies are presented aimed at further tracking the usefulness of ERP for detecting early cognitive dysfunctions in MS. All of the patients presented a relapsing remitting MS for less than 5 years with a moderate physical handicap and complained from their memory. They performed a neuropsychological set and ERP were elicited using the oddball paradigm in both modalities, visual and auditory. In the first study, 10 patients without cognitive dysfunction at the neuropsychological evaluation and 10 patients with an attention deficit participated with 10 age-matched controls. In the second study, 10 patients with memory impairment at the neuropsychological evaluation and 10 age-matched controls were included. Our data argue for an earlier modification of ERP parameters in the visual modality than in the auditory one, even before the modification of cognitive scores. In both studies, P300 parameters were correlated to neuropsychological performances (and especially to the attention examination in the first study and to memory tests in the second study) in both modalities. Taking into account the clinical usefulness of ERPs, it is nowadays important to include this electrophysiological method in evaluation and follow-up of MS, and not only using the auditory modality but also the visual presentation in order to detect earlier cognitive dysfunctions even before modification of neuropsychological performances.

  17. Targeting Premalignant Lesions: Implications for Early Breast Cancer Detection and Intervention

    DTIC Science & Technology

    2016-04-01

    1 AWARD NUMBER: W81XWH-14-1-0032 TITLE: Targeting Premalignant Lesions: Implications for Early Breast Cancer Detection and Intervention...ABSTRACT Breast cancer progression constitutes a multistep process through a series of intermediate hyperplastic and neoplastic stages to invasive...Considerable numbers of CAFs are frequently observed within the tumor- associated stroma of various human cancers , including those of the breast

  18. 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.

  19. 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.

  20. Low tube voltage CT for improved detection of pancreatic cancer: detection threshold for small, simulated lesions

    PubMed Central

    2012-01-01

    Background Pancreatic ductal adenocarcinoma is associated with dismal prognosis. The detection of small pancreatic tumors which are still resectable is still a challenging problem. The aim of this study was to investigate the effect of decreasing the tube voltage from 120 to 80 kV on the detection of pancreatic tumors. Methods Three scanning protocols was used; one using the standard tube voltage (120 kV) and current (160 mA) and two using 80 kV but with different tube currents (500 and 675 mA) to achieve equivalent dose (15 mGy) and noise (15 HU) as that of the standard protocol. Tumors were simulated into collected CT phantom images. The attenuation in normal parenchyma at 120 kV was set at 130 HU, as measured previously in clinical examinations, and the tumor attenuation was assumed to differ 20 HU and was set at 110HU. By scanning and measuring of iodine solution with different concentrations the corresponding tumor and parenchyma attenuation at 80 kV was found to be 185 and 219 HU, respectively. To objectively evaluate the differences between the three protocols, a multi-reader multi-case receiver operating characteristic study was conducted, using three readers and 100 cases, each containing 0–3 lesions. Results The highest reader averaged figure-of-merit (FOM) was achieved for 80 kV and 675 mA (FOM = 0,850), and the lowest for 120 kV (FOM = 0,709). There was a significant difference between the three protocols (p < 0,0001), when making an analysis of variance (ANOVA). Post-hoc analysis (students t-test) shows that there was a significant difference between 120 and 80 kV, but not between the two levels of tube currents at 80 kV. Conclusion We conclude that when decreasing the tube voltage there is a significant improvement in tumor conspicuity. PMID:22828284

  1. Comparative performance of multiview stereoscopic and mammographic display modalities for breast lesion detection

    SciTech Connect

    Webb, Lincoln J.; Samei, Ehsan; Lo, Joseph Y.; Baker, Jay A.; Ghate, Sujata V.; Kim, Connie; Soo, Mary Scott; Walsh, Ruth

    2011-04-15

    Purpose: Mammography is known to be one of the most difficult radiographic exams to interpret. Mammography has important limitations, including the superposition of normal tissue that can obscure a mass, chance alignment of normal tissue to mimic a true lesion and the inability to derive volumetric information. It has been shown that stereomammography can overcome these deficiencies by showing that layers of normal tissue lay at different depths. If standard stereomammography (i.e., a single stereoscopic pair consisting of two projection images) can significantly improve lesion detection, how will multiview stereoscopy (MVS), where many projection images are used, compare to mammography? The aim of this study was to assess the relative performance of MVS compared to mammography for breast mass detection. Methods: The MVS image sets consisted of the 25 raw projection images acquired over an arc of approximately 45 deg. using a Siemens prototype breast tomosynthesis system. The mammograms were acquired using a commercial Siemens FFDM system. The raw data were taken from both of these systems for 27 cases and realistic simulated mass lesions were added to duplicates of the 27 images at the same local contrast. The images with lesions (27 mammography and 27 MVS) and the images without lesions (27 mammography and 27 MVS) were then postprocessed to provide comparable and representative image appearance across the two modalities. All 108 image sets were shown to five full-time breast imaging radiologists in random order on a state-of-the-art stereoscopic display. The observers were asked to give a confidence rating for each image (0 for lesion definitely not present, 100 for lesion definitely present). The ratings were then compiled and processed using ROC and variance analysis. Results: The mean AUC for the five observers was 0.614{+-}0.055 for mammography and 0.778{+-}0.052 for multiview stereoscopy. The difference of 0.164{+-}0.065 was statistically significant with a

  2. 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

  3. Artifactual mutations resulting from DNA lesions limit detection levels in ultrasensitive sequencing applications

    PubMed Central

    Arbeithuber, Barbara; Makova, Kateryna D.; Tiemann-Boege, Irene

    2016-01-01

    The need in cancer research or evolutionary biology to detect rare mutations or variants present at very low frequencies (<10−5) poses an increasing demand on lowering the detection limits of available methods. Here we demonstrated that amplifiable DNA lesions introduce important error sources in ultrasensitive technologies such as single molecule PCR (smPCR) applications (e.g. droplet-digital PCR), or next-generation sequencing (NGS) based methods. Using templates with known amplifiable lesions (8-oxoguanine, deaminated 5-methylcytosine, uracil, and DNA heteroduplexes), we assessed with smPCR and duplex sequencing that templates with these lesions were amplified very efficiently by proofreading polymerases (except uracil), leading to G->T, and to a lesser extent, to unreported G->C substitutions at 8-oxoguanine lesions, and C->T transitions in amplified uracil containing templates. Long heat incubations common in many DNA extraction protocols significantly increased the number of G->T substitutions. Moreover, in ∼50-80% smPCR reactions we observed the random amplification preference of only one of both DNA strands explaining the known ‘PCR jackpot effect’, with the result that a lesion became indistinguishable from a true mutation or variant. Finally, we showed that artifactual mutations derived from uracil and 8-oxoguanine could be significantly reduced by DNA repair enzymes. PMID:27477585

  4. Artifactual mutations resulting from DNA lesions limit detection levels in ultrasensitive sequencing applications.

    PubMed

    Arbeithuber, Barbara; Makova, Kateryna D; Tiemann-Boege, Irene

    2016-12-01

    The need in cancer research or evolutionary biology to detect rare mutations or variants present at very low frequencies (<10(-5)) poses an increasing demand on lowering the detection limits of available methods. Here we demonstrated that amplifiable DNA lesions introduce important error sources in ultrasensitive technologies such as single molecule PCR (smPCR) applications (e.g. droplet-digital PCR), or next-generation sequencing (NGS) based methods. Using templates with known amplifiable lesions (8-oxoguanine, deaminated 5-methylcytosine, uracil, and DNA heteroduplexes), we assessed with smPCR and duplex sequencing that templates with these lesions were amplified very efficiently by proofreading polymerases (except uracil), leading to G->T, and to a lesser extent, to unreported G->C substitutions at 8-oxoguanine lesions, and C->T transitions in amplified uracil containing templates. Long heat incubations common in many DNA extraction protocols significantly increased the number of G->T substitutions. Moreover, in ∼50-80% smPCR reactions we observed the random amplification preference of only one of both DNA strands explaining the known 'PCR jackpot effect', with the result that a lesion became indistinguishable from a true mutation or variant. Finally, we showed that artifactual mutations derived from uracil and 8-oxoguanine could be significantly reduced by DNA repair enzymes. © The Author 2016. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

  5. 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. PMID:27818583

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

    PubMed

    Charisis, Vasileios S; Hadjileontiadis, Leontios J

    2016-10-21

    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.

  7. A fully automatic lesion detection method for DCE-MRI fat-suppressed breast images

    NASA Astrophysics Data System (ADS)

    Vignati, Anna; Giannini, Valentina; Bert, Alberto; Deluca, Massimo; Morra, Lia; Persano, Diego; Martincich, Laura; Regge, Daniele

    2009-02-01

    Dynamic Contrast Enhanced MRI (DCE-MRI) has today a well-established role, complementary to routine imaging techniques for breast cancer diagnosis such as mammography. Despite its undoubted clinical advantages, DCE-MRI data analysis is time-consuming and Computer Aided Diagnosis (CAD) systems are required to help radiologists. Segmentation is one of the key step of every CAD image processing pipeline, but most techniques available require human interaction. We here present the preliminary results of a fully automatic lesion detection method, capable of dealing with fat suppression image acquisition sequences, which represents a challenge for image processing algorithms due to the low SNR. The method is based on four fundamental steps: registration to correct for motion artifacts; anatomical segmentation to discard anatomical structures located outside clinically interesting lesions; lesion detection to select enhanced areas and false positive reduction based on morphological and kinetic criteria. The testing set was composed by 13 cases and included 27 lesions (10 benign and 17 malignant) of diameter > 5 mm. The system achieves a per-lesion sensitivity of 93%, while yielding an acceptable number of false positives (26 on average). The results of our segmentation algorithm were verified by visual inspection, and qualitative comparison with a manual segmentation yielded encouraging results.

  8. Detection of Occlusal Carious Lesion using the SoproLife(®) Camera: A Systematic Review.

    PubMed

    Doméjean, Sophie; Rongier, Julie; Muller-Bolla, Michéle

    2016-09-01

    The aim of this systematic review was to assess the in vivo scientific evidence regarding the ability of a recently developed light fluorescence device, SoproLife(®) (Sopro-Acteon group, La Ciotat, France) in detecting occlusal carious lesions. The PubMed database was searched for in vivo trials that evaluated the validity of the SoproLife(®) camera for the detection of occlusal carious lesions. Among the 11 articles originally identified with the keyword "Soprolife," only three articles were included. The three included surveys used the International Caries Detection and Assessment System (ICDAS)-II criteria as gold standard for the assessment of SoproLife(®) compared or not to other detection devices (DIAGNOdent(®) and Spectra Caries Detection Aid(®)). Two of the included studies reported only on permanent teeth or both primary and permanent teeth. The SoproLife(®) validity values varied markedly among studies with a sensitivity ranging between 0.43 and 0.95 and a specificity between 0.55 and 1. Interobserver reproducibility with the SoproLife(®) was reported in two of the three studies (0.98 and 0.72) and none of the studies reported about intraobserver reproducibility. No clear-cut conclusion can be made based on the three included clinical studies; further in vivo investigations are needed to confirm the validity of the SoproLife(®) camera in terms of detection of occlusal carious lesions.

  9. [Lesions Detected in Six Spanish Colorectal Cancer Screening Population Based Programmes. CRIBEA Project. Spain].

    PubMed

    Portillo Villares, Isabel; Arana-Arri, Eunate; Idigoras Rubio, Isabel; Espinás Piñol, Josep Alfons; Pérez Riquelme, Francisco; de la Vega Prieto, Mariola; González Aledo, Alvaro; Oceja Setien, Elena; Vanaclocha Espi, Mercedes; Ibáñez Cabanell, Josefa; Salas Trejo, Dolores

    2017-02-20

    In this study, the results of six Colorectal Cancer Screening Population Programmes are shown (Catalonia, Valence, Murcia, Cantabria, the Basque Country and the Canary Islands collected between 2005 and 2012. These programmes use the faeces occult blood test (FOBt) biennial. Objective: To determine and compare the results of lesions detected by the programmes, participation, sex, age and test used. Retrospective cohort study based on people invited, aged between 50-74 years, in at least a complete round. Lesions considered: Advanced Adenomas (AA), Colorectal Invasive Cancer (CRC) and both of them, known as Advanced Neoplasia (AN). Logistic Regression and time trends are used. 1,995,719 of invitations registered, with an average participation-rate of 46.7%. 21,228 Advanced Neoplasias (2,813 CRC and 18,415 AA). Differences in detection rates observed between programmes (varying from 15.1‰ to 35.8‰ between participants). Participation rates were related to lesions' detection rates (OR 1.25 in 40-60% of participation). . Inmunochemical qualitative test showed an OR of 4.79 and quantitative test an OR of 7.30 over the guaiac test. Men showed an OR of 2.73 with respect to women. In 2012 the Advanced Neoplasia rate for women and men was 33.1 and 14.2 by 1,000 participants. The test used was the most important factor for detecting lesions. Time trends showed an increase in detected lesions caused by the change of the type of test in 2010.

  10. Experimental comparison of lesion detectability for four fully-3D PET reconstruction schemes.

    PubMed

    Kadrmas, Dan J; Casey, Michael E; Black, Noel F; Hamill, James J; Panin, Vladimir Y; Conti, Maurizio

    2009-04-01

    The objective of this work was to evaluate the lesion detection performance of four fully-3D positron emission tomography (PET) reconstruction schemes using experimentally acquired data. A multi-compartment anthropomorphic phantom was set up to mimic whole-body (18)F-fluorodeoxyglucose (FDG) cancer imaging and scanned 12 times in 3D mode, obtaining count levels typical of noisy clinical scans. Eight of the scans had 26 (68)Ge "shell-less" lesions (6, 8-, 10-, 12-, 16-mm diameter) placed throughout the phantom with various target:background ratios. This provided lesion-present and lesion-absent datasets with known truth appropriate for evaluating lesion detectability by localization receiver operating characteristic (LROC) methods. Four reconstruction schemes were studied: 1) Fourier rebinning (FORE) followed by 2D attenuation-weighted ordered-subsets expectation-maximization, 2) fully-3D AW-OSEM, 3) fully-3D ordinary-Poisson line-of-response (LOR-)OSEM; and 4) fully-3D LOR-OSEM with an accurate point-spread function (PSF) model. Two forms of LROC analysis were performed. First, a channelized nonprewhitened (CNPW) observer was used to optimize processing parameters (number of iterations, post-reconstruction filter) for the human observer study. Human observers then rated each image and selected the most-likely lesion location. The area under the LROC curve ( A(LROC)) and the probability of correct localization were used as figures-of-merit. The results of the human observer study found no statistically significant difference between FORE and AW-OSEM3D ( A(LROC)=0.41 and 0.36, respectively), an increase in lesion detection performance for LOR-OSEM3D ( A(LROC)=0.45, p=0.076), and additional improvement with the use of the PSF model ( A(LROC)=0.55, p=0.024). The numerical CNPW observer provided the same rankings among algorithms, but obtained different values of A(LROC). These results show improved lesion detection performance for the reconstruction algorithms with

  11. Experimental Comparison of Lesion Detectability for Four Fully-3D PET Reconstruction Schemes

    PubMed Central

    Casey, Michael E.; Black, Noel F.; Hamill, James J.; Panin, Vladimir Y.; Conti, Maurizio

    2009-01-01

    The objective of this work was to evaluate the lesion detection performance of four fully-3D positron emission tomography (PET) reconstruction schemes using experimentally acquired data. A multi-compartment anthropomorphic phantom was set up to mimic whole-body 18F-fluorodeoxyglucose (FDG) cancer imaging and scanned 12 times in 3D mode, obtaining count levels typical of noisy clinical scans. Eight of the scans had 26 68Ge “shell-less” lesions (6, 8-, 10-, 12-, 16-mm diameter) placed throughout the phantom with various target:background ratios. This provided lesion-present and lesion-absent datasets with known truth appropriate for evaluating lesion detectability by localization receiver operating characteristic (LROC) methods. Four reconstruction schemes were studied: 1) Fourier rebinning (FORE) followed by 2D attenuation-weighted ordered-subsets expectation-maximization, 2) fully-3D AW-OSEM, 3) fully-3D ordinary-Poisson line-of-response (LOR-)OSEM; and 4) fully-3D LOR-OSEM with an accurate point-spread function (PSF) model. Two forms of LROC analysis were performed. First, a channelized nonprewhitened (CNPW) observer was used to optimize processing parameters (number of iterations, post-reconstruction filter) for the human observer study. Human observers then rated each image and selected the most-likely lesion location. The area under the LROC curve (ALROC) and the probability of correct localization were used as figures-of-merit. The results of the human observer study found no statistically significant difference between FORE and AW-OSEM3D (ALROC = 0.41 and 0.36, respectively), an increase in lesion detection performance for LOR-OSEM3D (ALROC = 0.45, p = 0.076), and additional improvement with the use of the PSF model (ALROC = 0.55, p = 0.024). The numerical CNPW observer provided the same rankings among algorithms, but obtained different values of ALROC. These results show improved lesion detection performance for the reconstruction algorithms with more

  12. The method for detecting small lesions in medical image based on sliding window

    NASA Astrophysics Data System (ADS)

    Han, Guilai; Jiao, Yuan

    2016-10-01

    At present, the research on computer-aided diagnosis includes the sample image segmentation, extracting visual features, generating the classification model by learning, and according to the model generated to classify and judge the inspected images. However, this method has a large scale of calculation and speed is slow. And because medical images are usually low contrast, when the traditional image segmentation method is applied to the medical image, there is a complete failure. As soon as possible to find the region of interest, improve detection speed, this topic attempts to introduce the current popular visual attention model into small lesions detection. However, Itti model is mainly for natural images. But the effect is not ideal when it is used to medical images which usually are gray images. Especially in the early stages of some cancers, the focus of a disease in the whole image is not the most significant region and sometimes is very difficult to be found. But these lesions are prominent in the local areas. This paper proposes a visual attention mechanism based on sliding window, and use sliding window to calculate the significance of a local area. Combined with the characteristics of the lesion, select the features of gray, entropy, corner and edge to generate a saliency map. Then the significant region is segmented and distinguished. This method reduces the difficulty of image segmentation, and improves the detection accuracy of small lesions, and it has great significance to early discovery, early diagnosis and treatment of cancers.

  13. Detection of equine herpesvirus 3 in equine skin lesions by polymerase chain reaction.

    PubMed

    Kleiboeker, Steven B; Chapman, Rodney K

    2004-01-01

    During a recent breeding season, ulcerative, pustular skin lesions were observed on the external genitalia of 2 mares and 1 stallion within a small herd. Based on the location and description of the skin lesions plus the clinical history, equine coital exanthema, caused by equine herpesvirus 3 (EHV3), was the primary differential diagnosis. Scrapings of skin lesions from the perineum of 2 mares were submitted for diagnostic evaluation. Virus isolation was attempted by inoculation of several cell lines of equine origin, but no cytopathic agent was detected. The skin scrapings were processed for DNA extraction, and polymerase chain reaction (PCR) amplification was performed for herpesvirus DNA polymerase and DNA-packaging protein (terminase) genes using nested, degenerate primers targeted to conserved regions of the herpesvirus genome. Products of the expected sizes were generated for both assays, and subsequent nucleotide sequencing of the amplification products established that EHV3 had been detected in DNA extracted from the skin lesions. Detection of EHV3 was confirmed using an EHV3-specific PCR assay targeted to the gC gene. Using the novel EHV3 nucleotide sequence identified in this report, a sensitive and specific PCR assay targeted to the highly conserved DNA polymerase gene was developed.

  14. Multiple sclerosis - etiology and diagnostic potential.

    PubMed

    Kamińska, Joanna; Koper, Olga M; Piechal, Kinga; Kemona, Halina

    2017-06-30

    Multiple sclerosis (MS) is a chronic inflammatory and demyelinating disease of autoimmune originate. The main agents responsible for the MS development include exogenous, environmental, and genetic factors. MS is characterized by multifocal and temporally scattered central nervous system (CNS) damage which lead to the axonal damage. Among clinical courses of MS it can be distinguish relapsing-remitting multiple sclerosis (RRMS), secondary progressive multiple sclerosis (SPSM), primary progressive multiple sclerosis (PPMS), and progressive-relapsing multiple sclerosis (RPMS). Depending on the severity of signs and symptoms MS can be described as benign MS or malignant MS. MS diagnosis is based on McDonald's diagnostic criteria, which link clinical manifestation with characteristic lesions demonstrated by magnetic resonance imaging (MRI), cerebrospinal fluid (CSF) analysis, and visual evoked potentials. Among CSF laboratory tests used to the MS diagnosis are applied: Tibbling & Link IgG index, reinbegrams, and CSF isoelectrofocusing for oligoclonal bands detection. It should be emphasized, that despite huge progress regarding MS as well as the availability of different diagnostics methods this disease is still a diagnostic challenge. It may result from fact that MS has diverse clinical course and there is a lack of single test, which would be of appropriate diagnostic sensitivity and specificity for quick and accurate diagnosis.

  15. Automated and interactive lesion detection and segmentation in uterine cervix images.

    PubMed

    Alush, Amir; Greenspan, Hayit; Goldberger, Jacob

    2010-02-01

    This paper presents a procedure for automatic extraction and segmentation of a class-specific object (or region) by learning class-specific boundaries. We describe and evaluate the method with a specific focus on the detection of lesion regions in uterine cervix images. The watershed segmentation map of the input image is modeled using a Markov random field (MRF) in which watershed regions correspond to binary random variables indicating whether the region is part of the lesion tissue or not. The local pairwise factors on the arcs of the watershed map indicate whether the arc is part of the object boundary. The factors are based on supervised learning of a visual word distribution. The final lesion region segmentation is obtained using a loopy belief propagation applied to the watershed arc-level MRF. Experimental results on real data show state-of-the-art segmentation results on this very challenging task that, if necessary, can be interactively enhanced.

  16. Parathyroid incidentalomas detected during thyroid ultrasonography and effect of chronic thyroiditis on false positive parathyroid lesions.

    PubMed

    Ozdemir, Didem; Arpaci, Dilek; Ucler, Rifki; Cuhaci, Neslihan; Ersoy, Reyhan; Cakir, Bekir

    2012-12-01

    We aimed to determine the prevalence of parathyroid incidentalomas in patients referred for thyroid ultrasonography (US) and investigate the role of chronic thyroiditis on false positive lesions. Patients suspected to have parathyroid lesions during thyroid US were recorded prospectively between August 2009 and January 2010. Patients referred for parathyroid US and patients with known high serum calcium or parathyroid hormone (PTH) levels were excluded. Suspected parathyroid lesions were defined as hypoechoic, homogeneous, solid lesions with regular margins located outside the thyroid lobe, most commonly inferior to the thyroid gland. Thyroid US was performed in 6,528 patients. There were 78 patients (1.19 %) (73 female and 5 male) with suspected parathyroid lesion. The diagnosis of a true parathyroid adenoma was confirmed in 6 (7.69 %) patients. In patients with true adenoma, mean serum calcium, phosphorus, and PTH levels were 10.57 ± 0.48 mg/dl, 3.03 ± 0.52 mg/dl, and 182.91 ± 46.62 pg/ml, respectively. Among 72 patients with false positive parathyroid lesion, antithyroid peroxidase antibody was positive in 50 (69.4 %), antithyroglobulin antibody was positive in 46 (63.9 %), and one of these antibodies were positive in 59 (81.9 %) patients. Also, 46 (63.9 %) of these patients had thyroid dysfunctions (43 hypothyroidism and 3 hyperthyroidism) and 59 (81.9 %) had chronic thyroiditis ultrasonographically. Parathyroid incidentaloma was detected in 0.09 % of patients referred for thyroid US. The presence of clinically or ultrasonographically chronic thyroiditis might cause inadvertent interpretation of a hypoechoic lesion as a parathyroid pathology during thyroid US.

  17. Diagnosis and management of benign, atypical, and indeterminate breast lesions detected on core needle biopsy.

    PubMed

    Neal, Lonzetta; Sandhu, Nicole P; Hieken, Tina J; Glazebrook, Katrina N; Mac Bride, Maire Brid; Dilaveri, Christina A; Wahner-Roedler, Dietlind L; Ghosh, Karthik; Visscher, Daniel W

    2014-04-01

    Imaging abnormalities detected by mammographic screening often lead to diagnostic evaluations, with suspicious abnormalities subjected to image-guided core needle biopsy (CNB) to exclude malignancy. Most CNBs reveal benign pathological alterations, termed benign breast disease (BBD). Adoption of CNB presents challenges with pathologic classification of breast abnormalities and management of patients with benign or atypical histological findings. Patient management and counseling after CNB diagnosis of BBD depends on postbiopsy determination of radiologic-pathologic concordancy. Communication between radiologists and pathologists is crucial in patient management. Management is dependent on the histological type of BBD. Patients with concordant pathologic imaging results can be reassured of benign biopsy findings and advised about the future risk of developing breast cancer. Surgical consultation is advised for patients with discordant findings, symptomatic patients, and high-risk lesions. This review highlights benign breast lesions that are encountered on CNB and summarizes management strategies. For this review, we conducted a search of PubMed, with no date limitations, and used the following search terms (or a combination of terms): atypical ductal hyperplasia, atypical hyperplasia, atypical lobular hyperplasia, benign breast disease, cellular fibroepithelial lesions, columnar cell lesions, complex sclerosing lesion, core needle biopsy, fibroadenomas, flat epithelial atypia, lobular carcinoma in situ, lobular neoplasia, mucocele-like lesions, phyllodes tumor, pseudoangiomatous stromal hyperplasia, radial scar, and vascular lesions. The selection of references included in this review was based on study relevance and quality. We used additional articles culled from the bibliographies of retrieved articles to examine the published evidence for risk factors of BBD. Copyright © 2014 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All

  18. Risk Stratification of Neck Lesions Detected Sonographically During the Follow-Up of Differentiated Thyroid Cancer.

    PubMed

    Lamartina, Livia; Grani, Giorgio; Biffoni, Marco; Giacomelli, Laura; Costante, Giuseppe; Lupo, Stefania; Maranghi, Marianna; Plasmati, Katia; Sponziello, Marialuisa; Trulli, Fabiana; Verrienti, Antonella; Filetti, Sebastiano; Durante, Cosimo

    2016-08-01

    The European Thyroid Association (ETA) has classified posttreatment cervical ultrasound findings in thyroid cancer patients based on their association with disease persistence/recurrence. The objective of the study was to assess this classification's ability to predict the growth and persistence of such lesions during active posttreatment surveillance of patients with differentiated thyroid cancer (DTC). This was a retrospective, observational study. The study was conducted at a thyroid cancer center in a large Italian teaching hospital. Center referrals (2005-2014) were reviewed and patients selected with pathologically-confirmed DTC; total thyroidectomy, with or without neck dissection and/or radioiodine remnant ablation; abnormal findings on two or more consecutive posttreatment neck sonograms; and subsequent follow-up consisting of active surveillance. Baseline ultrasound abnormalities (thyroid bed masses, lymph nodes) were classified according to the ETA system. Patients were divided into group S (those with one or more lesions classified as suspicious) and group I (indeterminate lesions only). We recorded baseline and follow-up clinical data through June 30, 2015. The main outcomes were patients with growth (>3 mm, largest diameter) of one or more lesions during follow-up and patients with one or more persistent lesions at the final visit. The cohort included 58 of the 637 DTC cases screened (9%). A total of 113 lesions were followed up (18 thyroid bed masses, 95 lymph nodes). During surveillance (median 3.7 y), group I had significantly lower rates than group S of lesion growth (8% vs 36%, P = .01) and persistence (64% vs 97%, P = .014). The median time to scan normalization was 2.9 years. The ETA's evidence-based classification of sonographically detected neck abnormalities can help identify papillary thyroid cancer patients eligible for more relaxed follow-up.

  19. An effective hair detection algorithm for dermoscopic melanoma images of skin lesions

    NASA Astrophysics Data System (ADS)

    Chakraborti, Damayanti; Kaur, Ravneet; Umbaugh, Scott; LeAnder, Robert

    2016-09-01

    Dermoscopic images are obtained using the method of skin surface microscopy. Pigmented skin lesions are evaluated in terms of texture features such as color and structure. Artifacts, such as hairs, bubbles, black frames, ruler-marks, etc., create obstacles that prevent accurate detection of skin lesions by both clinicians and computer-aided diagnosis. In this article, we propose a new algorithm for the automated detection of hairs, using an adaptive, Canny edge-detection method, followed by morphological filtering and an arithmetic addition operation. The algorithm was applied to 50 dermoscopic melanoma images. In order to ascertain this method's relative detection accuracy, it was compared to the Razmjooy hair-detection method [1], using segmentation error (SE), true detection rate (TDR) and false positioning rate (FPR). The new method produced 6.57% SE, 96.28% TDR and 3.47% FPR, compared to 15.751% SE, 86.29% TDR and 11.74% FPR produced by the Razmjooy method [1]. Because of the 7.27-9.99% improvement in those parameters, we conclude that the new algorithm produces much better results for detecting thick, thin, dark and light hairs. The new method proposed here, shows an appreciable difference in the rate of detecting bubbles, as well.

  20. Automatic detection and segmentation of ischemic lesions in computed tomography images of stroke patients

    NASA Astrophysics Data System (ADS)

    Vos, Pieter C.; Biesbroek, J. Matthijs; Weaver, Nick A.; Velthuis, Birgitta K.; Viergever, Max A.

    2013-03-01

    Stroke is the third most common cause of death in developed countries. Clinical trials are currently investigating whether advanced Computed Tomography can be of benefit for diagnosing stroke at the acute phase. These trials are based on large patients cohorts that need to be manually annotated to obtain a reference standard of tissue loss at follow-up, resulting in extensive workload for the radiologists. Therefore, there is a demand for accurate and reliable automatic lesion segmentation methods. This paper presents a novel method for the automatic detection and segmentation of ischemic lesions in CT images. The method consists of multiple sequential stages. In the initial stage, pixel classification is performed using a naive Bayes classifier in combination with a tissue homogeneity algorithm in order to localize ischemic lesion candidates. In the next stage, the candidates are segmented using a marching cubes algorithm. Regional statistical analysis is used to extract features based on local information as well as contextual information from the contra-lateral hemisphere. Finally, the extracted features are summarized into a likelihood of ischemia by a supervised classifier. An area under the Receiver Operating Characteristic curve of 0.91 was obtained for the identification of ischemic lesions. The method performance on lesion segmentation reached a Dice similarity coeficient (DSC) of 0.74+/-0.09, whereas an independent human observer obtained a DSC of 0.79+/-0.11 in the same dataset. The experiments showed that it is feasible to automatically detect and segment ischemic lesions in CT images, obtaining a comparable performance as human observers.

  1. 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.

  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. The impact of simulated motion blur on lesion detection performance in full-field digital mammography.

    PubMed

    Abdullah, Ahmed K; Kelly, Judith; Thompson, John D; Mercer, Claire E; Aspin, Rob; Hogg, Peter

    2017-07-01

    Motion blur is a known phenomenon in full-field digital mammography, but the impact on lesion detection is unknown. This is the first study to investigate detection performance with varying magnitudes of simulated motion blur. 7 observers (15 ± 5 years' reporting experience) evaluated 248 cases (62 containing malignant masses, 62 containing malignant microcalcifications and 124 normal cases) for 3 conditions: no blurring (0 mm) and 2 magnitudes of simulated blurring (0.7 and 1.5 mm). Abnormal cases were biopsy proven. Mathematical simulation was used to provide a pixel shift in order to simulate motion blur. A free-response observer study was conducted to compare lesion detection performance for the three conditions. The equally weighted jackknife alternative free-response receiver operating characteristic was used as the figure of merit. Test alpha was set at 0.05 to control probability of Type I error. The equally weighted jackknife alternative free-response receiver operating characteristic analysis found a statistically significant difference in lesion detection performance for both masses [F(2,22) = 6.01, p = 0.0084] and microcalcifications [F(2,49) = 23.14, p < 0.0001]. The figures of merit reduced as the magnitude of simulated blurring increased. Statistical differences were found between some of the pairs investigated for the detection of masses (0.0 vs 0.7 and 0.0 vs 1.5 mm) and all pairs for microcalcifications (0.0 vs 0.7, 0.0 vs 1.5 and 0.7 vs 1.5 mm). No difference was detected between 0.7 and 1.5 mm for masses. The mathematical simulation of motion blur caused a statistically significant reduction in lesion detection performance. These false-negative decisions could have implications for clinical practice. Advances in knowledge: This research demonstrates for the first time that motion blur has a negative and statistically significant impact on lesion detection performance in digital mammography.

  4. 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.

  5. 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.

  6. 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.

  7. The impact of breast structure on lesion detection in breast tomosynthesis

    NASA Astrophysics Data System (ADS)

    Kiarashi, Nooshin; Nolte, Loren W.; Lo, Joseph Y.; Segars, William P.; Ghate, Sujata V.; Samei, Ehsan

    2015-03-01

    Virtual clinical trials (VCT) can be carefully designed to inform, orient, or potentially replace clinical trials. The focus of this study was to demonstrate the capability of the sophisticated tools that can be used in the design, implementation, and performance analysis of VCTs, through characterization of the effect of background tissue density and heterogeneity on the detection of irregular masses in digital breast tomosynthesis. Twenty breast phantoms from the extended cardiactorso (XCAT) family, generated based on dedicated breast computed tomography of human subjects, were used to extract a total of 2173 volumes of interest (VOI) from simulated tomosynthesis images. Five different lesions, modeled after human subject tomosynthesis images, were embedded in the breasts, for a total of 6×2173 VOIs with and without lesions. Effects of background tissue density and heterogeneity on the detection of the lesions were studied by implementing a doubly composite hypothesis signal detection theory paradigm with location known exactly, lesion known exactly, and background known statistically. The results indicated that the detection performance as measured by the area under the receiver operating characteristic curve (ROC) deteriorated as density was increased, yielding findings consistent with clinical studies. The detection performance varied substantially across the twenty breasts. Furthermore, the log-likelihood ratio under H0 and H1 seemed to be affected by background tissue density and heterogeneity differently. Considering background tissue variability can change the outcomes of a VCT and is hence of crucial importance. The XCAT breast phantoms can address this concern by offering realistic modeling of background tissue variability based on a wide range of human subjects.

  8. Focal liver lesions at 3.0 T: lesion detectability and image quality with T2-weighted imaging by using conventional and dual-source parallel radiofrequency transmission.

    PubMed

    Kukuk, Guido M; Gieseke, Jürgen; Weber, Sebastian; Hadizadeh, Dariusch R; Nelles, Michael; Träber, Frank; Schild, Hans H; Willinek, Winfried A

    2011-05-01

    To prospectively compare T2-weighted single-shot turbo spin-echo (TSE) sequences performed with parallel and conventional radiofrequency (RF) transmission at 3.0 T for liver lesion detection, image quality, lesion conspicuity, and lesion contrast. After written informed consent and institutional review board approval, 52 consecutive patients (32 men, 20 women; mean age, 56.6 years ± 13.7 [standard deviation]) underwent routine magnetic resonance (MR) imaging with a clinical 3.0-T unit. Two independent readers reviewed images acquired with conventional and dual-source parallel RF transmission for detection of focal liver lesions, with separate reading of a third radiologist, including all available imaging findings, clinical history, and histopathologic findings, as reference. Image quality and lesion conspicuity were rated on five- and three-point evaluation scales, respectively. Contrast ratios between focal liver lesions and adjacent liver parenchyma were calculated. Significance was determined by using nonparametric Wilcoxon signed-rank and marginal homogeneity tests. With the reference standard, 106 index lesions were identified in 22 patients. Detection rate significantly improved from 87% (92 of 106) to 97% (103 of 106) (reader 1) and from 85% (90 of 106) to 96% (102 of 106) (reader 2) with parallel RF transmission (reader 1, P = .0078; reader 2, P = .002). Quality of parallel RF transmission images was assigned scores significantly higher, compared with quality of conventional RF transmission images (mean for reader 1, 2.88 ± 0.73 vs 4.04 ± 0.44; mean for reader 2, 2.81 ± 0.72 vs 4.04 ± 0.39; P < .0001 for both). Lesion conspicuity scores were significantly higher on parallel RF transmission images, compared with conventional RF transmission images (mean for reader 1, 2.02 ± 0.64 vs 2.92 ± 0.27; mean for reader 2, 2.06 ± 0.67 vs 2.90 ± 0.30; P < .0001 for both). Contrast ratios were significantly higher with parallel RF transmission (P < .05

  9. Orofacial manifestations in tuberous sclerosis.

    PubMed

    Scully, C

    1977-11-01

    Tuberous sclerosis is a rare congenital disorder with characteristic neurologic, dermatologic, and orofacial lesions. There have been very few case reports in the dental literature. Four cases demonstrating the range of orofacial anomalies and problems in management are presented.

  10. 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

  11. 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.

  12. 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. |

  13. 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

  14. Optical detection of (pre-)malignant lesions of the oral mucosa: autofluorescence characteristics of healthy mucosa

    NASA Astrophysics Data System (ADS)

    de Veld, Diana C. G.; Witjes, Max; Roodenburg, Jan L.; Star, Willem M.; Sterenborg, Hericus J. C. M.

    2001-10-01

    Previous clinical results demonstrate the potential of in vivo autofluorescence spectroscopy for early detection of (pre-)malignant lesions of the oral mucosa. For reliable diagnosis, it is necessary to study autofluorescence spectra of healthy mucosa first. We measured excitation-emission maps in healthy subjects and subjects with a history of cancer in the head -neck region. Our results show that different anatomical locations produce distinct autofluorescence spectra. Influences of, among others, smoking and drinking habits require further investigation.

  15. Standard examination and adjunctive techniques for detection of oral premalignant and malignant lesions.

    PubMed

    Kerr, A Ross; Shah, Sonal S

    2013-05-01

    This article outlines how to perform a standard comprehensive extraoral and intraoral examination and the existing commercially available adjunctive techniques for the early detection of oral cancer and premalignant lesions. Visualization-based techniques (e.g., autofluorescence and chemiluminescence), toluidine blue vital staining, cytopathologic tests and high-risk human papillomavirus testing are discussed in detail, including the indications and protocols for use, their advantages and disadvantages and clinical cases.

  16. Automatic detection and recognition of multiple macular lesions in retinal optical coherence tomography images with multi-instance multilabel learning

    NASA Astrophysics Data System (ADS)

    Fang, Leyuan; Yang, Liumao; Li, Shutao; Rabbani, Hossein; Liu, Zhimin; Peng, Qinghua; Chen, Xiangdong

    2017-06-01

    Detection and recognition of macular lesions in optical coherence tomography (OCT) are very important for retinal diseases diagnosis and treatment. As one kind of retinal disease (e.g., diabetic retinopathy) may contain multiple lesions (e.g., edema, exudates, and microaneurysms) and eye patients may suffer from multiple retinal diseases, multiple lesions often coexist within one retinal image. Therefore, one single-lesion-based detector may not support the diagnosis of clinical eye diseases. To address this issue, we propose a multi-instance multilabel-based lesions recognition (MIML-LR) method for the simultaneous detection and recognition of multiple lesions. The proposed MIML-LR method consists of the following steps: (1) segment the regions of interest (ROIs) for different lesions, (2) compute descriptive instances (features) for each lesion region, (3) construct multilabel detectors, and (4) recognize each ROI with the detectors. The proposed MIML-LR method was tested on 823 clinically labeled OCT images with normal macular and macular with three common lesions: epiretinal membrane, edema, and drusen. For each input OCT image, our MIML-LR method can automatically identify the number of lesions and assign the class labels, achieving the average accuracy of 88.72% for the cases with multiple lesions, which better assists macular disease diagnosis and treatment.

  17. Lectin-functionalized mesoporous silica nanoparticles for endoscopic detection of premalignant colonic lesions.

    PubMed

    Chen, Nai-Tzu; Souris, Jeffrey S; Cheng, Shih-Hsun; Chu, Chia-Hui; Wang, Yu-Chao; Konda, Vani; Dougherty, Urszula; Bissonnette, Marc; Mou, Chung-Yuan; Chen, Chin-Tu; Lo, Leu-Wei

    2017-08-01

    Colorectal cancer (CRC) is one of the leading causes of cancer-deaths worldwide. Methods for the early in situ detection of colorectal adenomatous polyps and their precursors - prior to their malignancy transformation into CRC - are urgently needed. Unfortunately at present, the primary diagnostic method, colonoscopy, can only detect polyps and carcinomas by shape/morphology; with sessile polyps more likely to go unnoticed than polypoid lesions. Here we describe our development of polyp-targeting, fluorescently-labeled mesoporous silica nanoparticles (MSNs) that serve as targeted endoscopic contrast agents for the early detection of colorectal polyps and cancer. In vitro cell studies, ex vivo histopathological analysis, and in vivo colonoscopy and endoscopy of murine colorectal cancer models, demonstrate significant binding specificity of our nanoconstructs to pathological lesions via targeting aberrant α-L-fucose expression. Our findings strongly suggest that lectin-functionalized fluorescent MSNs could serve as a promising endoscopic contrast agent for in situ diagnostic imaging of premalignant colonic lesions. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. 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.

  19. Pre-envelope deconvolution for increased lesion detection efficiency in ultrasonic imaging

    NASA Astrophysics Data System (ADS)

    Abbey, Craig K.; Zemp, Roger J.; Insana, Michael F.

    2003-05-01

    We use an ideal observer model to evaluate the efficiency of human observers detecting a simulated lesion in the presence of speckle, and the ability of pre-envelope deconvolution to improve performance in this task. We model the lesion as a localized area of increased scatter density, which translates into an area of higher variance in the ultrasound signal. Assuming the scattering function and electronic noise obey Gaussian distributions, the ideal observer for lesion detection is given by a quadratic function of the in-phase (I) and quadrature (Q) data. For comparison, human-observer performance is assessed through two-alternative forced-choice (2AFC) psychophysical studies after making a B-mode image by computing the magnitude (envelope) of the I and Q components. We also consider the effect of removing spatial correlations in the I and Q components, before computing the magnitude (pre-envelope deconvolution). Our Psychophysical studies indicate approximately a 4-fold improvement in detection efficiency with pre-envelope deconvolution.

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

    SciTech Connect

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

    2016-08-15

    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.

  1. 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

  2. Detecting and treating occlusal caries lesions: a cost-effectiveness analysis.

    PubMed

    Schwendicke, F; Stolpe, M; Meyer-Lueckel, H; Paris, S

    2015-02-01

    The health gains and costs resulting from using different caries detection strategies might not only depend on the accuracy of the used method but also the treatment emanating from its use in different populations. We compared combinations of visual-tactile, radiographic, or laser-fluorescence-based detection methods with 1 of 3 treatments (non-, micro-, and invasive treatment) initiated at different cutoffs (treating all or only dentinal lesions) in populations with low or high caries prevalence. A Markov model was constructed to follow an occlusal surface in a permanent molar in an initially 12-y-old male German patient over his lifetime. Prevalence data and transition probabilities were extracted from the literature, while validity parameters of different methods were synthesized or obtained from systematic reviews. Microsimulations were performed to analyze the model, assuming a German health care setting and a mixed public-private payer perspective. Radiographic and fluorescence-based methods led to more overtreatments, especially in populations with low prevalence. For the latter, combining visual-tactile or radiographic detection with microinvasive treatment retained teeth longest (mean 66 y) at lowest costs (329 and 332 Euro, respectively), while combining radiographic or fluorescence-based detections with invasive treatment was the least cost-effective (<60 y, >700 Euro). In populations with high prevalence, combining radiographic detection with microinvasive treatment was most cost-effective (63 y, 528 Euro), while sensitive detection methods combined with invasive treatments were again the least cost-effective (<59 y, >690 Euro). The suitability of detection methods differed significantly between populations, and the cost-effectiveness was greatly influenced by the treatment initiated after lesion detection. The accuracy of a detection method relative to a "gold standard" did not automatically convey into better health or reduced costs. Detection methods

  3. 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.

  4. Random forest learning of ultrasonic statistical physics and object spaces for lesion detection in 2D sonomammography

    NASA Astrophysics Data System (ADS)

    Sheet, Debdoot; Karamalis, Athanasios; Kraft, Silvan; Noël, Peter B.; Vag, Tibor; Sadhu, Anup; Katouzian, Amin; Navab, Nassir; Chatterjee, Jyotirmoy; Ray, Ajoy K.

    2013-03-01

    Breast cancer is the most common form of cancer in women. Early diagnosis can significantly improve lifeexpectancy and allow different treatment options. Clinicians favor 2D ultrasonography for breast tissue abnormality screening due to high sensitivity and specificity compared to competing technologies. However, inter- and intra-observer variability in visual assessment and reporting of lesions often handicaps its performance. Existing Computer Assisted Diagnosis (CAD) systems though being able to detect solid lesions are often restricted in performance. These restrictions are inability to (1) detect lesion of multiple sizes and shapes, and (2) differentiate between hypo-echoic lesions from their posterior acoustic shadowing. In this work we present a completely automatic system for detection and segmentation of breast lesions in 2D ultrasound images. We employ random forests for learning of tissue specific primal to discriminate breast lesions from surrounding normal tissues. This enables it to detect lesions of multiple shapes and sizes, as well as discriminate between hypo-echoic lesion from associated posterior acoustic shadowing. The primal comprises of (i) multiscale estimated ultrasonic statistical physics and (ii) scale-space characteristics. The random forest learns lesion vs. background primal from a database of 2D ultrasound images with labeled lesions. For segmentation, the posterior probabilities of lesion pixels estimated by the learnt random forest are hard thresholded to provide a random walks segmentation stage with starting seeds. Our method achieves detection with 99.19% accuracy and segmentation with mean contour-to-contour error < 3 pixels on a set of 40 images with 49 lesions.

  5. Electron microscopic detection of human papillomavirus particles in oral proliferative lesions.

    PubMed

    Broich, G; Sasaki, T

    1989-11-01

    Human papilloma virus (HPV) has been demonstrated in a series of benign proliferative lesions of skin and mucosae. To prove the distribution of HPV in the oral proliferative lesions at the ultrastructural level, we performed electron microscopic analysis of 10 specimens taken from 5 patients through large excisional biopsy. All of them were diagnosed pathologically as fibropapilloma. In each patient, specimens were taken from both clinically evident proliferative lesions and clinically normal surrounding mucosa. Obtained specimens were fixed in a glutaraldehyde solution and processed for routine ultrathin sectioning. Before electron microscopic observation, the tissue sections on copper grids were subjected to amylase digestion of glycogen granules. Spherical viral particles of 40-55 nm in diameter were detected the non-keratinized epithelial cells in all specimens examined. Of particular interest were the large amounts of viral particles found in the cytoplasmic matrix and nuclei (especially on their chromatin masses) of the cells in intermediate and surface layers, which did not form a crystal array. All the membranous cell organelles of epithelial cells were, however, devoid of viral particles. Some viral particles were distributed in the extracellular spaces of an intermediate layer. Viral particles were hardly observed in the cells of a basal/suprabasal and prickle cell layers. There were no significant differences in the HPV distribution between the cells derived from the proliferative lesion and those derived from the surrounding normal mucosa.

  6. A Fillable Micro-Hollow Sphere Lesion Detection Phantom Using Superposition

    PubMed Central

    DiFilippo, Frank P.; Gallo, Sven L.; Klatte, Ryan S.; Patel, Sagar

    2010-01-01

    The lesion detection performance of SPECT and PET scanners is most commonly evaluated with a phantom containing hollow spheres in a background chamber at a specified radionuclide contrast ratio. However there are limitations associated with a miniature version of a hollow sphere phantom for small animal SPECT and PET scanners. One issue is that the “wall effect” associated with zero activity in the sphere wall and fill port causes significant errors for small diameter spheres. Another issue is that there are practical difficulties in fabricating and in filling very small spheres (< 3 mm diameter). The need for lesion detection performance assessment of small-animal scanners has motivated our development of a micro-hollow sphere phantom that utilizes the principle of superposition. The phantom is fabricated by stereolithography and has interchangeable sectors containing hollow spheres with volumes ranging from 1 to 14 μL (diameters ranging from 1.25 to 3.0 mm). A simple 60° internal rotation switches the positions of three such sectors with their corresponding background regions. Raw data from scans of each rotated configuration are combined and reconstructed to yield superposition images. Since the sphere counts and background counts are acquired separately, the wall effect is eliminated. The raw data are subsampled randomly prior to summation and reconstruction to specify the desired spheres-to-background contrast ratio of the superposition image. A set of images with multiple contrast ratios is generated for visual assessment of lesion detection thresholds. To demonstrate the utility of the phantom, data were acquired with a multi-pinhole SPECT/CT scanner. Micro-liter syringes were successful in filling the small hollow spheres, and the accuracy of the dispensed volume was validated through repeated filling and weighing of the spheres. The phantom’s internal rotation and the data analysis process were successful in producing the expected superposition

  7. Pigmented skin lesion detection using random forest and wavelet-based texture

    NASA Astrophysics Data System (ADS)

    Hu, Ping; Yang, Tie-jun

    2016-10-01

    The incidence of cutaneous malignant melanoma, a disease of worldwide distribution and is the deadliest form of skin cancer, has been rapidly increasing over the last few decades. Because advanced cutaneous melanoma is still incurable, early detection is an important step toward a reduction in mortality. Dermoscopy photographs are commonly used in melanoma diagnosis and can capture detailed features of a lesion. A great variability exists in the visual appearance of pigmented skin lesions. Therefore, in order to minimize the diagnostic errors that result from the difficulty and subjectivity of visual interpretation, an automatic detection approach is required. The objectives of this paper were to propose a hybrid method using random forest and Gabor wavelet transformation to accurately differentiate which part belong to lesion area and the other is not in a dermoscopy photographs and analyze segmentation accuracy. A random forest classifier consisting of a set of decision trees was used for classification. Gabor wavelets transformation are the mathematical model of visual cortical cells of mammalian brain and an image can be decomposed into multiple scales and multiple orientations by using it. The Gabor function has been recognized as a very useful tool in texture analysis, due to its optimal localization properties in both spatial and frequency domain. Texture features based on Gabor wavelets transformation are found by the Gabor filtered image. Experiment results indicate the following: (1) the proposed algorithm based on random forest outperformed the-state-of-the-art in pigmented skin lesions detection (2) and the inclusion of Gabor wavelet transformation based texture features improved segmentation accuracy significantly.

  8. Effect of dose reduction on the detection of mammographic lesions: A mathematical observer model analysis

    SciTech Connect

    Chawla, Amarpreet S.; Samei, Ehsan; Saunders, Robert; Abbey, Craig; Delong, David

    2007-08-15

    The effect of reduction in dose levels normally used in mammographic screening procedures on the detection of breast lesions were analyzed. Four types of breast lesions were simulated and inserted into clinically-acquired digital mammograms. Dose reduction by 50% and 75% of the original clinically-relevant exposure levels were simulated by adding corresponding simulated noise into the original mammograms. The mammograms were converted into luminance values corresponding to those displayed on a clinical soft-copy display station and subsequently analyzed by Laguerre-Gauss and Gabor channelized Hotelling observer models for differences in detectability performance with reduction in radiation dose. Performance was measured under a signal known exactly but variable detection task paradigm in terms of receiver operating characteristics (ROC) curves and area under the ROC curves. The results suggested that luminance mapping of digital mammograms affects performance of model observers. Reduction in dose levels by 50% lowered the detectability of masses with borderline statistical significance. Dose reduction did not have a statistically significant effect on detection of microcalcifications. The model results indicate that there is room for optimization of dose level in mammographic screening procedures.

  9. Left atrial dysfunction detected by speckle tracking in patients with systemic sclerosis

    PubMed Central

    2014-01-01

    Background Cardiac involvement is a relevant clinical finding in systemic sclerosis (SSc) and is associated with poor prognosis. Left atrial (LA) remodeling and/or dysfunction can be an early sign of diastolic dysfunction. Two-dimensional speckle tracking echocardiography (STE) is a novel and promising tool for detecting very early changes in LA myocardial performance. Aim To assess whether STE strain parameters may detect early alterations in LA function in SSc patients. Methods Forty-two SSc patients (Group 1, age 50 ± 14 years, 95% females) without clinical evidence for cardiac involvement and 42 age- and gender-matched control subjects (Group 2, age 49 ± 13 years, 95% females) were evaluated with comprehensive 2D and Doppler echocardiography, including tissue Doppler imaging analysis. Positive peak left atrial longitudinal strain (ϵ pos peak), second positive left atrial longitudinal strain (sec ϵ pos peak), and negative left atrial longitudinal strain (ϵ neg peak) were measured using a 12-segment model for the LA, by commercially available semi-automated 2D speckle-tracking software (EchoPac PC version 108.1.4, GE Healthcare, Horten, Norway). Results All SSc patients had a normal left ventricular ejection fraction (63.1 ± 4%). SSc patients did not differ from controls in E/A (Group 1 = 1.1 ± 0.4 vs Group 2 = 1.3 ± 0.4, p = .14) or pulmonary arterial systolic pressure (Group 1 = 24.1 ± 8 mmHg vs Group 2 = 21 ± 7 mmHg, p = .17). SSc patients did not show significantly different indexed LA volumes (Group 1 = 24.9 ± 5.3 ml/m2 vs Group 2 = 24.7 ± 4.4 ml/m2, p = .8), whereas E/e’ ratio was significantly higher in SSc (Group 1 = 7.6 ± 2.4 vs Group 2 = 6.5 ± 1.7, p<0.05), although still within normal values. LA strain values were significantly different between the two groups (ϵ pos peak Group 1 = 31.3 ± 4.2% vs Group 2 = 35.0 ± 7.6%, p

  10. 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,