Automatic Dti-based Parcellation Of The Corpus Callosum Through The Watershed Transform

Introduction: Parcellation of the corpus callosum (CC) in the midsagittal cross-section of the brain is of utmost importance for the study of diffusion properties within this structure. The complexity of this operation comes from the absence of macroscopic anatomical landmarks to help in dividing the CC into different callosal areas. In this paper we propose a completely automatic method for CC parcellation using diffusion tensor imaging (DTI). Methods: A dataset of 15 diffusion MRI volumes from normal subjects was used. For each subject, the midsagital slice was automatically detected based on the Fractional Anisotropy (FA) map. Then, segmentation of the CC in the midsgital slice was performed using the hierarchical watershed transform over a weighted FA-map. Finally, parcellation of the CC was obtained through the application of the watershed transform from chosen markers. Results: Parcellation results obtained were consistent for fourteen of the fifteen subjects tested. Results were similar to the ones obtained from tractography-based methods. Tractography confirmed that the cortical regions associated with each obtained CC region were consistent with the literature. Conclusions: A completely automatic DTI-based parcellation method for the CC was designed and presented. It is not based on tractography, which makes it fast and computationally inexpensive. While most of the existing methods for parcellation of the CC determine an average behavior for the subjects based on population studies, the proposed method reflects the diffusion properties specific for each subject. Parcellation boundaries are found based on the diffusion properties within each individual CC, which makes it more reliable and less affected by differences in size and shape among subjects.302132143Aboitiz, F., Scheibel, A.B., Fisher, R.S., Zaidel, E., Fiber composition of the human corpus callosum (1992) Brain Research, 598 (1-2), pp. 143-153. , http://dx.doi.org/10.1016/0006-8993(92)90178-CBasser, P.J., Pierpaoli, C., Microstructural and physiological features of tissues elucidated by quantitative-diffusion-tensor MRI (1996) Journal of Magnetic Resonance, Series B, 111 (3), pp. 209-219. , http://dx.doi.org/10.1006/jmrb.1996.0086Basser, P.J., Mattiello, J., LeBihan, D., MR diffusion tensor spectroscopy and imaging (1994) Biophysical Journal, 66 (1), pp. 259-267. , http://dx.doi.org/10.1016/S0006-3495(94)80775-1Beucher, S., Lantuéjoul, C., (1979) Use of watersheds in contour detection, , In: International Workshop on Image Processing: Proceedings of the International Workshop on Image Processing: Real-time Edge and Motion Detection/EstimationRennes, FranceBeucher, S., Meyer, F., (1992) The morphological approach to segmentation: The Watershed Transformation, pp. 433-481. , Mathematical Morphology in Image Processing (CRC Press)Biegon, A., Eberling, J.L., Richardson, B.C., Roos, M.S., Wong, S.T., Reed, B.R., Jagust, W.J., Human corpus callosum in aging and alzheimer's disease: A magnetic resonance imaging study (1994) Neurobiology of Aging, 15 (4), pp. 393-397. , http://dx.doi.org/10.1016/0197-4580(94)90070-1Chepuri, N.B., Yen, Y.F., Burdette, J.H., Li, H., Moody, D.M., Maldjian, J.A., Diffusion anisotropy in the corpus callosum (2002) American journal of Neuroradiology, 23 (5), pp. 803-808. , PMid: 12006281DeLacoste-Utamsing, C., Holloway, R., Sexual dimorphism in the human corpus callosum (1982) Science, 216 (4553), pp. 1431-1432. , http://dx.doi.org/10.1126/science.7089533Digabel, H., Lantuéjoul, C., Iterative algorithms, pp. 85-99. , In: European Symposium Quantitative Analysis of Microstructures in Material Science, Biology and Medicine: Proceedings of the 2nd European Symposium Quantitative Analysis of Microstructures in Material Science, Biology and Medicine1978Dougherty, R.F., Ben-Shachar, M., Bammer, R., Brewer, A.A., Wandell, B.A., Functional organization of human occipital-callosal fiber tracts (2005) Proceedings of the National Academy of Sciences of the United States of America, 102 (20), pp. 7350-7355. , http://dx.doi.org/10.1073/pnas.0500003102, PMid: 15883384 PMCid: PMC1129102Duara, R., Kushch, A., Gross-Glenn, K., Barker, W.W., Jallad, B., Pascal, S., Loewenstein, D.A., Lubs, H., Neuroanatomic differences between dyslexic and normal readers on magnetic resonance imaging scans (1991) Archives of Neurology, 48 (4), pp. 410-416. , http://dx.doi.org/10.1001/archneur.1991.00530160078018, PMid: 2012516Falcão, A.X., Stolfi, J., Lotufo, R.A., The image foresting transform: Theory, algorithms, and applications (2004) IEEE Transactions on Pattern Analysis and Machine Intelligence, 26 (1), pp. 19-29. , http://dx.doi.org/10.1109/TPAMI.2004.1261076, PMid: 15382683Freitas, P., Rittner, L., Appenzeller, S., Lotufo, R.A., Watershed-based segmentation of the midsagittal section of the corpus callosum in diffusion MRI IEEE Computer Society, pp. 274-280. , In: Graphics, Patterns and Images, Conference on: Proceedings of the 24th Conference on Graphics, Patterns and Images2011Grimaud, M., A new measure of contrast: The dynamics (1992) Image Algebra and Morphological Image Processing III, 1769, pp. 292-305. , http://dx.doi.org/10.1117/12.60650Habib, M., Gayraud, D., Oliva, A., Regis, J., Salamon, G., Khalil, R., Effects of handedness and sex on the morphology of the corpus callosum: A study with brain magnetic resonance imaging (1991) Brain and Cognition, 16 (1), pp. 41-61. , http://dx.doi.org/10.1016/0278-2626(91)90084-LHampel, H., Teipel, S.J., Alexander, G.E., Horwitz, B., Teichberg, D., Schapiro, M.B., Rapoport, S.I., Corpus callosum atrophy is a possible indicator of region-and cell type-specific neuronal degeneration in Alzheimer disease: A magnetic resonance imaging analysis (1998) Archives of Neurology, 55 (2), pp. 193-198. , http://dx.doi.org/10.1001/archneur.55.2.193, PMid: 9482361Hofer, S., Frahm, J., Topography of the human corpus callosum revisited-comprehensive fiber tractography using diffusion tensor magnetic resonance imaging (2006) NeuroImage, 32 (3), pp. 989-994. , http://dx.doi.org/10.1016/j.neuroimage.2006.05.044, PMid: 16854598Huang, H., Zhang, J., Jiang, H., Wakana, S., Poetscher, L., Miller, M.I., van Zijl, P.C., Mori, S., DTI tractography based parcellation of white matter: Application to the mid-sagittal morphology of corpus callosum (2005) NeuroImage, 26 (1), pp. 195-205. , http://dx.doi.org/10.1016/j.neuroimage.2005.01.019, PMid: 15862219Johnson, S.C., Farnworth, T., Pinkston, J.B., Bigler, E.D., Blatter, D.D., Corpus callosum surface area across the human adult life span: Effect of age and gender (1994) Brain Research Bulletin, 35 (4), pp. 373-377. , http://dx.doi.org/10.1016/0361-9230(94)90116-3Körbes, A., Lotufo, R.A., Analysis of the watershed algorithms based on the Breadth-First and Depth-First exploring methods (2009) IEEE Computer Society, pp. 133-140. , http://dx.doi.org/10.1109/SIBGRAPI.2009.43, In: Computer Graphics and Image Processing, Brazilian Symposium on: Proceedings of the 22th Brazilian Symposium on Computer Graphics and Image Processing2009Rio de Janeiro, BrazilLarsen, J.P., Höien, T., Odegaard, H., Magnetic resonance imaging of the corpus callosum in developmental dyslexia (1992) Cognitive Neuropsychology, 9 (2), pp. 123-134. , http://dx.doi.org/10.1080/02643299208252055Lotufo, R.A., Falcão, A.X., The ordered queue and the optimality of the watershed approaches Kluwer Academic Publishersv, pp. 341-350. , http://dx.doi.org/10.1007/0-306-47025-X_37, In: Mathematical Morphology and its Applications to Image and Signal Processing: Proceedings of the 5th International Symposium on Mathematical Morphology and its Applications to Image and Signal Processing2000, 18Mori, S., Crain, B.J., Chacko, V.P., van Zijl, P.C.M., Three-dimensional tracking of axonal projections in the brain by magnetic resonance imaging (1999) Annals of Neurology, 45 (2), pp. 265-269. , http://dx.doi.org/10.1002/1531-8249(199902)45:2265::AID-ANA213.0.CO;2-3Narr, K.L., Thompson, P.M., Sharma, T., Moussal, J., Cannestra, A.F., Toga, A.W., Mapping morphology of the corpus callosum in schizophrenia (2000) Cerebral cortex (New York, NY, 1991), 10 (1), pp. 40-49. , http://dx.doi.org/10.1093/cercor/10.1.40Narr, K.L., Cannon, T.D., Woods, R.P., Thompson, P.M., Kim, S., Asunction, D., van Erp, T.G., Toga, A.W., Genetic Contributions to Altered Callosal Morphology in Schizophrenia The Journal of Neuroscience, 22 (9), pp. 3720-3729. , PMid: 11978848O'Dwyer, L., Lamberton, F., Bokde, A.L.W., Ewers, M., Faluyi, Y.O., Tanner, C., Mazoyer, B., Hampel, H., Multiple indices of diffusion identifies white matter damage in mild cognitive impairment and Alzheimer's disease (2011) PLoS one, 6 (6), pp. e21745. , http://dx.doi.org/10.1371/journal.pone.0021745, PMid: 21738785 PMCid: PMC3128090Oh, J.S., Suk Park, K., Chan Song, I., Ju Kim, S., Hwang, J., Chung, A., Kyoon Lyoo, I., Fractional anisotropy-based divisions of midsagittal corpus callosum (2005) Neuroreport, 16 (4), pp. 317-320. , http://dx.doi.org/10.1097/00001756-200503150-00002Park, H.J., Kim, J.J., Lee, S.K., Seok, J.H., Chun, J., Kim, D.I., Lee, J.D., Corpus callosal connection mapping using cortical gray matter parcellation and DT-MRI (2008) Human Brain Mapping, 29 (5), pp. 503-516. , http://dx.doi.org/10.1002/hbm.20314, PMid: 17133394Park, J.S., Yoon, U., Kwak, K.C., Seo, S.W., Kim, S.I., Na, D.L., Lee, J.M., The relationships between extent and microstructural properties of the midsagittal corpus callosum in human brain (2011) NeuroImage, 56 (1), pp. 174-184. , http://dx.doi.org/10.1016/j.neuroimage.2011.01.065, PMid: 21281715Rajapakse, J.C., Giedd, J.N., Rumsey, J.M., Vaituzis, A.C., Hamburger, S.D., Rapoport, J.L., Regional MRI measurements of the corpus callosum: A methodological and developmental study (1996) Brain and Development, 18 (5), pp. 379-388. , http://dx.doi.org/10.1016/0387-7604(96)00034-4Rumsey, J.M., Casanova, M., Mannheim, G.B., Patronas, N., De Vaughn, N., Hamburger, S.D., Aquino, T., Corpus callosum morphology, as measured with MRI, in dyslexic men Biological Psychiatry, 39 (9), pp. 769-775. , http://dx.doi.org/10.1016/0006-3223(95)00225-1Rosas, H.D., Lee, S.Y., Bender, A.C., Zaleta, A.K., Vangel, M., Yu, P., Fischl, B., Hersch, S.M., Altered white matter microstructure in the corpus callosum in Huntington's disease: Implications for cortical disconnection (2010) NeuroImage, 49 (4), pp. 2995-3004. , http://dx.doi.org/10.1016/j.neuroimage.2009.10.015, PMid: 19850138 PMCid: PMC3725957Thompson, P.M., Narr, K.L., Blanton, R.E., Toga, A.W., Mapping structural alterations of the corpus callosum during brain development and degeneration (2003) Proceedings of the NATO ASI on the corpus callosum, pp. 93-130Von Plessen, K., Lundervold, A., Duta, N., Heiervang, E., Klauschen, F., Smievoll, A.I., Ersland, L., Hugdahl, K., Less developed corpus callosum in dyslexic subjects-a structural MRI study (2002) Neuropsychologia, 40 (7), pp. 1035-1044. , http://dx.doi.org/10.1016/S0028-3932(01)00143-9Wahl, M., Lauterbach-Soon, B., Hattingen, E., Jung, P., Singer, O., Volz, S., Klein, J.C., Ziemann, U., Human motor corpus callosum: Topography, somatotopy, and link between microstructure and function (2007) Journal of Neuroscience, 27 (45), pp. 12132-12138. , http://dx.doi.org/10.1523/JNEUROSCI.2320-07.2007, PMid: 17989279Witelson, S.F., Hand and sex differences in the isthmus and genu of the human corpus callosum. A postmortem morphological study (1989) Brain, 112 (PART 3), pp. 799-835. , http://dx.doi.org/10.1093/brain/112.3.799, PMid: 2731030Witelson, S.F., Goldsmith, C.H., The relationship of hand preference to anatomy of the corpus callosum in men (1991) Brain Research, 545 (1-2), pp. 175-182. , http://dx.doi.org/10.1016/0006-8993(91)91284-

Possible role of 3He impurities in solid 4He

We use a quantum lattice gas model to describe essential aspects of the motion of 4He atoms and of 3He impurities in solid 4He. This study suggests that 3He impurities bind to defects and promote 4He atoms to interstitial sites which can turn the bosonic quantum disordered crystal into a metastable supersolid. It is suggested that defects and interstitial atoms are produced during the solid 4He nucleation process where the role of 3He impurities (in addition to the cooling rate) is known to be important even at very small (1 ppm) impurity concentration. It is also proposed that such defects can form a glass phase during the 4He solid growth by rapid cooling.Comment: 4 two-column Revtex pages, 4 figures. Europhysics Letters (in Press

Determining erosion rates in allchar (Macedonia) to revive the lorandite neutrino experiment

205 Tl in the lorandite (TiAsS2) mine of Allchar (Majdan, FYR Macedonia) is transformed to 205 Pb by cosmic ray reactions with muons and neutrinos. At depths of more than 300 m, muogenic production would be sufficiently low for the 4.3Ma old lorandite deposit to be used as a natural neutrino detector. Unfortunately, the Allchar deposit currently sits at a depth of only 120m below the surface, apparently making the lorandite experiment technically infeasible. We here present 25 erosion rate estimates for the Allchar area using in situ produced cosmogenic 36 Cl in carbonates and 10 Be in alluvial quartz. The new measurements suggest long-Term erosion rates of 100-120mMa-1 in the silicate lithologies that are found at the higher elevations of the Majdanksa River valley, and 200-280mMa -1 in the underlying marbles and dolomites. These values indicate that the lorandite deposit has spent most of its existence at depths of more than 400 m, sufficient for the neutrinogenic 205 Pb component to dominate the muon contribution. Our results suggest that this unique particle physics experiment is theoretically feasible and merits further development

Web-based Platform For Collaborative Medical Imaging Research

Medical imaging research depends basically on the availability of large image collections, image processing and analysis algorithms, hardware and a multidisciplinary research team. It has to be reproducible, free of errors, fast, accessible through a large variety of devices spread around research centers and conducted simultaneously by a multidisciplinary team. Therefore, we propose a collaborative research environment, named Adessowiki, where tools and datasets are integrated and readily available in the Internet through a web browser. Moreover, processing history and all intermediate results are stored and displayed in automatic generated web pages for each object in the research project or clinical study. It requires no installation or configuration from the client side and offers centralized tools and specialized hardware resources, since processing takes place in the cloud.941

Observation of non-classical rotational inertia in bulk solid 4He

In recent torsional oscillator experiments by Kim and Chan (KC), a decrease of rotational inertia has been observed in solid 4He in porous materials and in a bulk annular channel. This observation strongly suggests the existence of "non-classical rotational inertia" (NCRI), i.e. superflow, in solid 4He. In order to study such a possible "supersolid" phase, we perform torsional oscillator experiments for cylindrical solid 4He samples. We have observed decreases of rotational inertia below 200 mK for two solid samples (pressures P = 4.1 and 3.0 MPa). The observed NCRI fraction at 70 mK is 0.14 %, which is about 1/3 of the fraction observed in the annulus by KC. Our observation is the first experimental confirmation of the possible supersolid finding by KC.Comment: 6 pages, 3 firures, submitted to J. Low Temp. Phys. (Proceedings of QFS2006

Guest editorial: special issue on vision-based human activity recognition

sem informação301585

Zero-point vacancies in quantum solids

A Jastrow wave function (JWF) and a shadow wave function (SWF) describe a quantum solid with Bose--Einstein condensate; i.e. a supersolid. It is known that both JWF and SWF describe a quantum solid with also a finite equilibrium concentration of vacancies x_v. We outline a route for estimating x_v by exploiting the existing formal equivalence between the absolute square of the ground state wave function and the Boltzmann weight of a classical solid. We compute x_v for the quantum solids described by JWF and SWF employing very accurate numerical techniques. For JWF we find a very small value for the zero point vacancy concentration, x_v=(1.4\pm0.1) x 10^-6. For SWF, which presently gives the best variational description of solid 4He, we find the significantly larger value x_v=(1.4\pm0.1) x 10^-3 at a density close to melting. We also study two and three vacancies. We find that there is a strong short range attraction but the vacancies do not form a bound state.Comment: 19 pages, submitted to J. Low Temp. Phy

Continuous cerebral function monitoring in neonatal intensive care

Peer Reviewe

An open, multi-vendor, multi-field-strength brain MR dataset and analysis of publicly available skull stripping methods agreement

This paper presents an open, multi-vendor, multi-field strength magnetic resonance (MR) T1-weighted volumetric brain imaging dataset, named Calgary-Campinas-359 (CC-359). The dataset is composed of images of older healthy adults (29-80 years) acquired on scanners from three vendors (Siemens, Philips and General Electric) at both 1.5 T and 3 T. CC-359 is comprised of 359 datasets, approximately 60 subjects per vendor and magnetic field strength. The dataset is approximately age and gender balanced, subject to the constraints of the available images. It provides consensus brain extraction masks for all volumes generated using supervised classification. Manual segmentation results for twelve randomly selected subjects performed by an expert are also provided. The CC-359 dataset allows investigation of 1) the influences of both vendor and magnetic field strength on quantitative analysis of brain MR; 2) parameter optimization for automatic segmentation methods; and potentially 3) machine learning classifiers with big data, specifically those based on deep learning methods, as these approaches require a large amount of data. To illustrate the utility of this dataset, we compared to the results of a supervised classifier, the results of eight publicly available skull stripping methods and one publicly available consensus algorithm. A linear mixed effects model analysis indicated that vendor (p - value < 0.001) and magnetic field strength (p - value < 0.001) have statistically significant impacts on skull stripping results170482494CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP311228/2014-3; 157534/2015-488881.062158/2014-012013/07559-3; 2013/23514-0; 2016/18332-

Two-body correlations and the superfluid fraction for nonuniform systems

We extend the one-body phase function upper bound on the superfluid fraction in a periodic solid (a spatially ordered supersolid) to include two-body phase correlations. The one-body current density is no longer proportional to the gradient of the one-body phase times the one-body density, but rather it depends also on two-body correlation functions. The equations that simultaneously determine the one-body and two-body phase functions require a knowledge of one-, two-, and three-body correlation functions. The approach can also be extended to disordered solids. Fluids, with two-body densities and two-body phase functions that are translationally invariant, cannot take advantage of this additional degree of freedom to lower their energy.Comment: 13 page