In Reply: Cranioplasty Reverses Dysfunction of the Solutes Distribution in the Brain Parenchyma After Decompressive Craniectomy.

Abstract

BACKGROUND Solutes distribution by the intracranial cerebrospinal fluid (CSF) fluxes along perivascular spaces and through interstitial fluid (ISF) play a key role in the clearance of brain metabolites, with essential functions in maintaining brain homeostasis. OBJECTIVE To investigate the impact of decompressive craniectomy (DC) and cranioplasty (CP) on the efficacy of solutes distribution by the intracranial CSF and ISF flux. METHODS Mice were allocated in 3 groups: sham surgery, DC, and DC followed by CP. The solutes distribution in the brain parenchyma was assessed using T1 magnetic resonance imaging after injection of DOTA-Gadolinium in the cisterna magna. This evaluation was performed at an early time point following DC (after 2 d) and at a later time point (after 15 d). We evaluated the solutes distribution in the whole brain and in the region underneath the DC area. RESULTS Our results demonstrate that the global solutes distribution in the brain parenchyma is impaired after DC in mice, both at early and late time-points. However, there was no impact of DC on the solutes distribution just under the craniectomy. We then provide evidence that this impairment was reversed by CP. CONCLUSION The solute distribution in the brain parenchyma by the CSF and ISF is impaired by DC, a phenomenon reversed by CP.