Visualization of thalamic calcium influx with quantitative susceptibility mapping as a potential imaging biomarker for repeated mild traumatic brain injury

Publication date: Available online 12 June 2019Source: NeuroImageAuthor(s): Ferdinand Schweser, Jenni Kyyriäinen, Marilena Preda, Asla Pitkänen, Kathryn Toffolo, Austin Poulsen, Kaitlynn Donahue, Benett Levy, David PoulsenAbstractA key event in the pathophysiology of traumatic brain injury (TBI) is the influx of substantial amounts of Ca2+ into neurons, particularly in the thalamus. Detection of this calcium influx in vivo would provide a window into the biochemical mechanisms of TBI with potentially significant clinical implications. In the present work, our central hypothesis was that the Ca2+ influx could be imaged in vivo with the relatively recent MRI technique of quantitative susceptibility mapping (QSM). Wistar rats were divided into five groups: naive controls, sham-operated experimental controls, single mild TBI, repeated mild TBI, and single severe TBI. We employed the lateral fluid percussion injury (FPI) model, which replicates clinical TBI without skull fracture, performed 9.4 Tesla MRI with a 3D multi-echo gradient-echo sequence at weeks 1 and 4 post-injury, computed susceptibility maps using V-SHARP and the QUASAR-HEIDI technique, and performed histology. Sham, experimental controls animals, and injured animals did not demonstrate calcifications at 1 week after the injury. At week 4, calcifications were found in the ipsilateral thalamus of 25–50% of animals after a single TBI and 83% of animals after repeated mild TBI. The location and appearance of calcifi...

Source: NeuroImage - June 14, 2019 Category: Neuroscience Source Type: research