Time course of optic nerve sheath dilation: In vitro response characteristics to controlled pressure elevations.

Background: Optic nerve sheath (ONS) dilation indicates intracranial pressure elevation under clinical conditions but limited data exist with regard to the dynamics of sheath expansion.

Objective: To assess the time course of ONS widening and its stability under controlled pressure conditions in vitro.

Methods: Pre-defined pressure steps up to 65 mmHg were applied to the perineural space of ex-vivo human optic nerves (n = 16).