[Voyage en Italie : 1824-1830]. , Monument connu sous le nom de chapelle de Phalaris, sur une Echelle de 0,010 P.M. : [élévation principale, élévation latérale, plan d'ensemble et détail de l'ante, profils de l'ante et du soubassement] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 179

[Voyage en Italie : 1824-1830]. , Porte de la chapelle de Phalaris à Agrigente, sur une Echelle de 0,40 P.M. : [profil de la corniche surmontant le linteau, élévation de la porte] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 181

[Voyage en Italie : 1824-1830]. , Temple de la Concorde à Agrigente, sur une Echelle de 0,005 P.M. : [plan] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 183

[Voyage en Italie : 1824-1830]. , Temple d'Esculape, sur une Echelle de 0,005 P.M. : [élévation principale, plan d'ensemble, coupe longitidinale et deux profils de détails] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 185

[Voyage en Italie : 1824-1830]. , Temple de Junon Lucine à Agrigente, sur une Echelle de 0,005 P.M. : [plan d'ensemble, coupe longitudinale, détail d'un claveau de l'entablement] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 190

[Voyage en Italie : 1824-1830]. , S. Gennaro de Poveri à Naples, sur une échelle de 0,001 1/2 PM : [plan d'ensemble, coupe longitdinale et élévation principale] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 225

[Voyage en Italie : 1824-1830]. , Tombeau de L. Munacius [sic] Plancus : sur une échelle de 0,010 pm : [coupe, trois profils, plan] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 170

[Voyage en Italie : 1824-1830]. , Baptistère, Sur une Echelle de 0,005 P.M. : [élévation] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 144

[Voyage en Italie : 1824-1830]. , Baptistère. Eglise de St Jean, Sur une Echelle de 0,005 P.M. : [plan du rez-de-chaussée (partie gauche) et au niveau des tribunes (partie droite)] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 143

[Voyage en Italie : 1824-1830]. , Eglise dell' Annunziata, Sur une Echelle de 0,002 1/2 PM : [plan d'ensemble de l'église et de ses abords] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 124

[Voyage en Italie : 1824-1830]. , Palais de La Farnesina. Sur une Echelle de 0,10 P.M. : [deux coupes partielles, plan du rez-de-chaussée, vue perspective depuis la route] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 628

New Developments and Applications of the MP2RAGE Sequence - Focusing the Contrast and High Spatial Resolution R1 Mapping.

MR structural T1-weighted imaging using high field systems (>3T) is severely hampered by the existing large transmit field inhomogeneities. New sequences have been developed to better cope with such nuisances. In this work we show the potential of a recently proposed sequence, the MP2RAGE, to obtain improved grey white matter contrast with respect to conventional T1-w protocols, allowing for a better visualization of thalamic nuclei and different white matter bundles in the brain stem. Furthermore, the possibility to obtain high spatial resolution (0.65 mm isotropic) R1 maps fully independent of the transmit field inhomogeneities in clinical acceptable time is demonstrated. In this high resolution R1 maps it was possible to clearly observe varying properties of cortical grey matter throughout the cortex and observe different hippocampus fields with variations of intensity that correlate with known myelin concentration variations.

GREGOROVIUS, Ferdinand, Atenais, Herder Editorial, Barcelona, 2009, 228 p., ISBN: 978-84-254-2582-0

Siempre es motivo de gozo releer un clásico moderno. En esta ocasión se trata de Ferdinand Gregorovius, cuya Atenais ha publicado recientemente Herder en una magnífica traducción (la primera en lengua española) de José Antonio Molina Gómez, profesor de la Universidad de Murcia. Herder prosigue de esta manera la línea editorial, iniciada hace ya algunos años,de publicar las biografías de grandes figuras de la antigüedad, entre las que cabe contar las dedicadas a Aníbal, Cleopatra, Augusto, Calígula, Constantino I, Juliano o Teodosio I.

Brain Connectivity Analysis in Children. Effects of Prematurity. and Prenatal Growth Restriction

Introduction: Survival of children born prematurely or with very low birth weight has increased dramatically, but the long term developmental outcome remains unknown. Many children have deficits in cognitive capacities, in particular involving executive domains and those disabilities are likely to involve a central nervous system deficit. To understand their neurostructural origin, we use DTI. Structurally segregated and functionally regions of the cerebral cortex are interconnected by a dense network of axonal pathways. We noninvasively map these pathways across cortical hemispheres and construct normalized structural connection matrices derived from DTI MR tractography. Group comparisons of brain connectivity reveal significant changes in fiber density in case of children with poor intrauterine grown and extremely premature children (gestational age<28 weeks at birth) compared to control subjects. This changes suggest a link between cortico-axonal pathways and the central nervous system deficit. Methods: Sixty premature born infants (5-6 years old) were scanned on clinical 3T scanner (Magnetom Trio, Siemens Medical Solutions, Erlangen, Germany) at two hospitals (HUG, Geneva and CHUV, Lausanne). For each subject, T1-weighted MPRAGE images (TR/TE=2500/2.91,TI=1100, resolution=1x1x1mm, matrix=256x154) and DTI images (30 directions, TR/TE=10200/107, in-plane resolution=1.8x1.8x2mm, 64 axial, matrix=112x112) were acquired. Parent(s) provided written consent on prior ethical board approval. The extraction of the Whole Brain Structural Connectivity Matrix was performed following (Cammoun, 2009 and Hagmann, 2008). The MPARGE images were registered using an affine registration to the non-weighted-DTI and WM-GM segmentation performed on it. In order to have equal anatomical localization among subjects, 66 cortical regions with anatomical landmarks were created using the curvature information, i.e. sulcus and gyrus (Cammoun et al, 2007; Fischl et al, 2004; Desikan et al, 2006) with freesurfer software (http://surfer.nmr.mgh.harvard.edu/). Tractography was performed in WM using an algorithm especially designed for DTI/DSI data (Hagmann et al., 2007) and both information were then combined in a matrix. Each row and column of the matrix corresponds to a particular ROI. Each cell of index (i,j) represents the fiber density of the bundle connecting the ROIs i and j. Subdividing each cortical region, we obtained 4 Connectivity Matrices of different resolution (33, 66, 125 and 250 ROI/hemisphere) for each subject . Subjects were sorted in 3 different groups, namely (1) control, (2) Intrauterine Growth Restriction (IUGR), (3) Extreme Prematurity (EP), depending on their gestational age, weight and percentile-weight score at birth. Group-to-group comparisons were performed between groups (1)-(2) and (1)-(3). The mean age at examination of the three groups were similar. Results: Quantitative analysis were performed between groups to determine fibers density differences. For each group, a mean connectivity matrix with 33ROI/hemisphere resolution was computed. On the other hand, for all matrix resolutions (33,66,125,250 ROI/hemisphere), the number of bundles were computed and averaged. As seen in figure 1, EP and IUGR subjects present an overall reduction of fibers density in both interhemispherical and intrahemispherical connections. This is given quantitatively in table 1. IUGR subjects presents a higher percentage of missing fiber bundles than EP when compared to control subjects (~16% against 11%). When comparing both groups to control subjects, for the EP subjects, the occipito-parietal regions seem less interhemispherically connected whilst the intrahemispherical networks present lack of fiber density in the lymbic system. Children born with IUGR, have similar reductions in interhemispherical connections than the EP. However, the cuneus and precuneus connections with the precentral and paracentral lobe are even lower than in the case of the EP. For the intrahemispherical connections the IUGR group preset a loss of fiber density between the deep gray matter structures (striatum) and the frontal and middlefrontal poles, connections typically involved in the control of executive functions. For the qualitative analysis, a t-test comparing number of bundles (p-value<0.05) gave some preliminary significant results (figure 2). Again, even if both IUGR and EP appear to have significantly less connections comparing to the control subjects, the IUGR cohort seems to present a higher lack of fiber density specially relying the cuneus, precuneus and parietal areas. In terms of fiber density, preliminary Wilcoxon tests seem to validate the hypothesis set by the previous analysis. Conclusions: The goal of this study was to determine the effect of extreme prematurity and poor intrauterine growth on neurostructural development at the age of 6 years-old. This data indicates that differences in connectivity may well be the basis for the neurostructural and neuropsychological deficit described in these populations in the absence of overt brain lesions (Inder TE, 2005; Borradori-Tolsa, 2004; Dubois, 2008). Indeed, we suggest that IUGR and prematurity leads to alteration of connectivity between brain structures, especially in occipito-parietal and frontal lobes for EP and frontal and middletemporal poles for IUGR. Overall, IUGR children have a higher loss of connectivity in the overall connectivity matrix than EP children. In both cases, the localized alteration of connectivity suggests a direct link between cortico-axonal pathways and the central nervous system deficit. Our next step is to link these connectivity alterations to the performance in executive function tests.