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[en] We have used diffusion tensor tractography (DTT) for the evaluation of the somatotopic organization of corticospinal tracts (CSTs) in the posterior limb of the internal capsule (PLIC) and cerebral peduncle (CP). We imaged the brains of nine healthy right-handed subjects. We used a spin-echo echo-planar imaging (EPI) sequence with 12 diffusion- sensitized directions. DTT was calculated with an angular threshold of 35 degrees and a fractional anistropy (FA) threshold of 0.25. We determined the location of the CSTs by using two regions of interest (ROI) at expected areas of the pons and expected areas of the lateral half of the PLIC, in the left hemisphere of the brain. Fiber tracts crossing these two ROIs and the precentral gyrus (PCG) were defined as CSTs. Four new ROIs were then defined for the PCG, from the medial to lateral direction, as ROI 1 (medial) to ROI 4 (lateral). Finally, we defined each fiber tract of the CSTs between the pons and each ROI in the PCG by using two ROIs methods. In all subjects, the CSTs were organized along the long axis of the PLIC, and the hand fibers were located anterior to the foot fibers. The CSTs showed transverse orientation in the CP, and the hand fibers were located usually medial to the foot fibers. Corticospinal tracts are organized along the long axis of the PLIC and the horizontal direction of the CP
[en] To study craniopharyngiomas using different MR sequences to detect semiological patterns that aid in the characterization of the different components. We performed a retrospective MR study of 17 patients with confirmed craniopharyngioma. T1-weighted spin-echo, proton density-weighted, T2-weighted gradient-echo, T1-weighted (after administration of gadolinium), T1-weighted inversion recovery and phase and opposed-phase gradient echo sequences were employed to distinguish the different patterns. The semiologic patterns considered in MR were: solid-tissue, blood, protein, fat and fluid. A solid pole was detected in all the patients. There was a cystic component in 88.2% of cases; the protein pattern was observed in 52.9%, blood in 29.4%, fluid in 23.5% and fat in 11.7%. The coexistence of three patterns was detected in 29.4% and of two patterns in 58.8%. The calcium pattern was viewed in 75% of the patients studied with CT, with four patterns coexisting in 25%, three patterns in 41.6% and two patterns in 25%. MR detects different semiologic components in craniopharyngiomas, although it is necessary to employ certain unusual sequences in order to distinguish some patterns from others. (Author) 22 refs
[en] We present two patients who were found to have Sprengel's deformity on the basis of clinical and radiological evidence when they came to the Emergency Room of our hospital for other causes. We describe this entity, which was diagnosed by means of plain chest X-ray and review the pertinent literature. (Author) 9 refs
[en] To ascertain the sonographic changes of cerebral development in the newborn infant according to the postconceptional age and to assess the sonographic predictability of postconceptional age. Retrospectively, 251 consecutive normal brain sonograms were analyzed. The postconceptional age of the newborn infant ranged from 26 to 44 weeks (male: 123, female: 128). We made a score with sonographic patterns of the sylvian fissure, the sulcal development, the echogenecity of periventricular white matter (PVWM), and cortex-subcortex (C-SC) differentiation. The scoring systems were as followed; Open Y-shape (a point) and close Y-shape (two points) of the sylvain fissure; Lissencephalic pattern (a point), intermediate pattern (two points), and mature form (three points) of the sulcus: Discrete increased echogenecity of PVWN along the entire lateral ventricular wall (a point), indistant margin and intermediate extent (two points), and family localized to trigonal area (three points) of PVWM echogenecity: Indistant (a point), broad and faint (two points), and definitely linear (three points) C-SC differentiation. We identified the sonographic developmental change according to postconceptional age. And we classified the maturity of brain with 15 grades using the sonographic score. Correlation between the sonographic grades for cerebral development and the postconceptional age were statistically analyzed. Sonography showed immature brain (score 1 for sylvain fissure, sulcal pattern, echogenecity of PVWM, and C-SC differentiation) until 28 postconceptional weeks (PCW) of the newborn infant. All sylvain fissures had been converted to Y-shape until 35 PCW. Mature form for sulcal pattern, echogenecity of PVWM, and C-SC differentiation appears since 34-35 PCW. Conversion to the mature forms was detected in about 98% (191 out of 194 cases) of sulcal pattern after 38 PCW, all cases of echogenecity of PVWM after 40 PCW, and C-SC differentiation after 41 postconceptional weeks. And sonographic grades for cerebral development were well correlated with the postconceptional age (r=0.90, p<0.0001). Morphologic changes of the sylvian fissure, the sulcal pattern, the echogenecity of PVWM, and the C-SC differentiation on sonography were identified with increasing postconceptional age. And sonographic grades were well correlated with the postconceptional age. In conclusion, sonography may be a convenient and helpful method to evaluated the cerebral developmental changes of the newborn and to predict the postconceptional age.
[en] We report a case of cerebral toxoplasmosis in a patient with stage IV C1 AIDS who presented hyperdense CT images 13 days after beginning antitoxoplasma treatment. These lesions could be caused by calcifications or blood. The attenuation values lead us to believe that they are calcium. Intracranial calcification in adult cerebral toxoplasmosis is an uncommon finding. Its presence in AIDS patients should not suggest any etiology other than toxoplasmosis. (Author) 16 refs
[en] The purpose of this study was to shorten and simplify the procedure of filter retrieval after carotid stenting with cerebral protecting devices. We propose a retrieval method with a soft-tip guiding catheter, which eliminates the step of balloon exchange and introduction of a retriever catheter for the protection filter. The technique was successfully used in our last 60 consecutive patients. One transient deficit occurred. In conclusion, retrieval of the filter with a soft coaxial catheter after carotid stenting is a feasible and safe method and may simplify cerebrovascular protection during stenting.
[en] The handedness of seventy-five persons without evidence of neurological disease, was assessed with a standardised test. An analysis of the CT scans of the same persons was performed to determine (1) presence and lateralisation of frontal and occipital 'petalia', (2) width of frontal and occipital lobes of each hemisphere, (3) direction of straight sinus deviation. Results suggest that handedness and cerebral asymmetries are independent variables. There were no significant differences between right-handers and non-right handers. Also there was no significant differences between strongly left-handed and ambidextrous individuals, nor were there differences between right-handers with or without family history of left-handedness. Irrespective of handedness, left occipital 'petalia' was more common than right (p<0.01), right frontal petalia was more common than left (p<0.01), and straight sinus deviation was more commonly toward the right. The study does not support the concept that cerebral 'symmetry' or 'reverse asymmetry' are associated with left-handedness or ambidexterity. The noted asymmetries are more likely to be direct correlates of cerebral language dominance, than of handedness. Outside forces acting on the bone may also contribute to the asymmetries. CT scan may be of value as a direct predictor of cerebral dominance. (author)