Stephan Erberich PhD, PRESENTER: Nothing to Disclose

Abstract: HTML Purpose: Non-invasive fMRI and DTI during the neonatal period have tremendous potential to understand normal and abnormal brain development. MRI is challenging in neonates who are at high risk of infection, hypothermia and dehydration. Optimal BOLD and diffusion sensitivity is limited by the small filling factor in adult MRI equipment. We used a novel MR compatible incubator (MRCI) and a neonatal volume head coil to test the hypothesis, that fMRI of passive sensory-motor and visual tasks combined with DTI of white matter tracts and myelination development in the most vulnerable patient population can be investigated with unparalleled image quality and safety. Methods and Materials: 20 sedated neonatal patients (GA 28-44week) of NICU were referred for clinical MRI using the MRCI/NVHC. Axial acquisition on a GE CVi 1.5T MR: fMRI with GR-EPI (TR3000, TE50, FOV150, 64x64, 2.3x2.3x3mm); DTI of 6 diffusion directions (TR6000, TE80, B700, FOV150, 128x128, 1.8x1.8x3); T2 FSE anatomical imaging. Passive stimulation of both hands independently provoking a grasp movement by repeated in-/deflating of an air bulb versus rest, and a visual flicker stimulation versus darkness were performed (RARARA paradigm). Statistical Parametric Mapping (SPM99) was used for spatial and functional processing. DTI tensors were calculated to find anisotropic diffusion and tracts. Maps and tracts were merged onto the T2 image. Results: All patients performed fMRI/DTI before awakening. We observed: SNR>3, head movement<0.41mm/<0.53degree. BOLD with Z-values>3.43 associated with focal activation was found for the sensory-motor experiments in the contra-lateral left, right, or both primary motor areas (M1), sensory areas, and brainstem. Decreased signal was found in functional contra-lateral M1. Consistent increased BOLD was found in the primary visual cortex (V1). Combined fMRI and DTI demonstrated correlation between white matter tract development and cortical activation. Conclusion: Our experiments demonstrate, that fMRI can be obtained in this vulnerable population. The MRCI ensures improved SNR, stable physiology for imaging and BOLD sensitivity, and safety. Combining functional and white matter tract imaging can contribute to observe the rapid functional development in the neonates. In conclusion more comprehensive research targeting specific functional components using this approach will provide new insight of normal and abnormal brain development..      

Erberich PhD, S, Developmental Neuroimaging of Neonates with fMRI and DTI.  Radiological Society of North America 2003 Scientific Assembly and Annual Meeting, November 30 - December 5, 2003 ,Chicago IL. http://archive.rsna.org/2003/3100877.html