MRI characterization of early CNS transport kinetics post intrathecal gadolinium injection: Trends of subarachnoid and parenchymal distribution in healthy volunteers

To quantify CSF transport kinetics and brain glymphatic distribution using MRI following intrathecal injection of gadolinium contrast in healthy adults. Eight completely healthy volunteer subjects underwent intrathecal injection of gadolinium via image guided lumbar puncture and serial MRI's at six subsequent time points up to 11 h post-injection. Rate of enhancement and deposition were calculated for various regions and lobes of the brain. Normalized cranial data revealed that gadolinium in the intracranial CSF spaces peaked within 1–3 h and started to decrease at 7 h. In some regions of the brain parenchyma, such as the cerebral cortex and white matter, enhancement was increasing after 11 h. Differential rates of uptake between the parietal and frontal (p = 0.0003), cingulate (p = 0.002) and temporal (p = 0.018) lobes were shown as well as a several fold change between various cortical regions. Lastly, a linear regression comparing laterality between 35 cortical regions yielded (R2 = 0.90, p