In vivo glycocalyx assessment in aneurysmal subarachnoid hemorrhage patients: protocol for a prospective observational feasibility study

Traditionally, the search for DCI biomarkers has focused on systemic measurements of cerebrovascular breakdown products, which may vary due to metabolism and renal or hepatic clearance. In vivo assessment of the glycocalyx by SDF imaging is a minimally invasive method that allows for direct, local, and dynamic evaluation of the microcirculation. Given that the conjunctiva is vascularized by the ophthalmic artery branching off the internal carotid artery, it may better reflect cerebral microvascular changes associated with DCI. If feasible, in vivo glycocalyx measurements could serve as a valuable biomarker for monitoring DCI in aSAH patients, potentially offering superior predictive value compared to systemic measurements of glycocalyx breakdown products.