Sudden infant death syndrome is the leading cause of postneonatal infant mortality in industrialized nations. A subset of SIDS may be the result of an intrinsic defect in brain anatomy, in particular of the subcortical ascending arousal network, whose arousal pathways originate in the brainstem.
We use a multimodal and multiscale imaging approach to study the structure and connectivity of the postmortem infant brainstem in a control subject. We used whole brain and brainstem structural and diffusion MRI at various resolution. However, even at high resolution, ex vivo MRI is unable to provide sufficient contrast to segment the brainstem nuclei and tracts due to their size and the lack of myelination. We turned to Optical Coherence Tomography, which rely on intrinsic optical properties at an isotropic resolution of 3.5 µm and validate our results using histology.
A brainstem is imaged via the entire pipeline, the OCT data set is segmented and all the modalities are registered into the same space for comparison and analysis.
This work lays the foundation to compare the brainstem connectivity between SIDS cases and controls, with the potential to identify biomarkers and abnormalities of the disease not detectable by standard histopathological techniques.