Chronology of normal brain myelination in newborns with MR imaging

Transcription

1 Chronology of normal brain myelination in newborns with MR imaging Poster No.: C-0577 Congress: ECR 2012 Type: Authors: Keywords: DOI: Scientific Exhibit F. Fernandez Usagre; Sevilla/ES Neuroradiology brain, Pediatric, MR, Imaging sequences, Congenital /ecr2012/C-0577 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 15

2 Purpose To show the normal maturation of neonatal brain through MRI images obtained with T1 and T2 sequences and establish the temporal sequence in the first 18 months of life. Methods and Materials We analysed imaging findings of 15 full-term newborns who underwent MRI at 1.5 Tesla unit. the study protocol consisting of axial T1 and T2-weighted images. Results Normal myelination of the human brain is a process that begins around the fifth month of fetal life and culminates at about 24 months of life, following an established and predictable pattern. Normally, myelination progresses from caudal to cranial, dorsal and ventral from the in and out, maturing before the sensory fibers than motor or association fibers, in relation to the areas used in the early stages of life and phylogenetic development. This process or any alteration in the normal pattern can be detected by MRI and you can even evaluate the signs and symptoms in relation to the alteration seen in the image. At birth, T1-weighted image shows a brighter gray matter than the white matter. On T2- weighted imaging the white matter is brighter than gray. As myelination progresses, the signal of mature areas changes, increasing on T1-images and decreasing signal on T2, which allows differentiation of immature or pathological areas. For educational purposes we have divided the brain maturation in several stages, although in practice, this process is dynamic and these stages are overlapping. Brain imaging study at birth, at 3-4 months, 8-12 months and months. Page 2 of 15

3 At birth (presentation 1): These areas are myelinated: medulla oblongata, dorsal midbrain, cerebellar peduncles, posterior limb of internal capsule, corona radiata radiation and toward the outside of the ventral thalamus, prerolandic cortex, medial occipital cortex (around the calcarine fissure) and the posterior insula (related to the auditory area). 3-4 months (presentation 2): Deep white matter of the cerebellar hemispheres, middle cerebellar peduncle, ventral brainstem, corticospinal tract and optical radiation. Supratentorial-previously-myelinated areas are now larger, extending to the corona radiata and posterior corpus callosum months (slide 3): It seems clear anteroposterior gradient, showing a nearly complete myelination in the posterior brain and fossa posterior. Remains immature frontal subcortical white matter months (slide 4): The normal brain myelination is complete, except for the area terminalis, located lateral to the ventricular atria and whose maturity can not be completed until the second or third decade of life. Images for this section: Page 3 of 15

4 Fig. 1: Myelination at birth Page 4 of 15

5 Fig. 2: Myelination at birth Page 5 of 15

6 Fig. 3: Myelination at birth Page 6 of 15

7 Fig. 4: Myelination at third or fourth month Page 7 of 15

8 Fig. 5: Myelination at third or fourth month Page 8 of 15

9 Fig. 6: Myelination at third or fourth month Page 9 of 15

10 Fig. 10: Myelination at seventh-twelfth month Page 10 of 15

11 Fig. 9: Myelination at seventh-twelfth month Page 11 of 15

12 Fig. 8: Myelination at seventh-twelfth month Page 12 of 15

13 Fig. 7: Myelination at seventh-twelfth month Page 13 of 15

14 Fig. 11: Myelination at fifteenth-eighteenth month Page 14 of 15

15 Conclusion MRI, using T1 and T2 sequences, can assess the degree of brain maturation with respect the patient age and can demostrate an alteration in the chronology of this process or abnormal myelination. References 1.- Pediatric Brain and Spine: An atlas of MRI and Spectroscopy. Ed. Springer L.M. Ketonen, A. Hiwatashi, R. Sidhu, P.L. Wertteson. 2.- MR Imaging in Whitte Matter Diseases of Brain and Spinal Cord. Ed. Springer M. Filippi, N. de Stefano, V. Donsset, J.C. McGowan. 3.- Diagnostic Neuroradiology. Ed. Mosby Anne G. Osborn MD. 4.- A. James Barkovich MD, Bent O. Kjos MD, Donald E. Jackson Jr. MD, David Norman MD. "Normal Maturation of the Neonatal and Infant Brain: MR Imaging at 1.5T". Radiology 1988; 166: Personal Information Page 15 of 15