SPP1 and Dilatation of the cerebral artery: Plasma OPN N-half levels were also significantly increased at all time points after SAH compared with control patients with unruptured intracranial aneurysms (37.76 pmol/L [15.19–86.92, p < 0.001] at days 1–3; 81.77 pmol/L [26.31–131.73, p < 0.001] at days 4–6; 80.88 pmol/L [40.25–136.43, p < 0.001] at days 7–9; and 48.48 pmol/L [18.03–105.95, p < 0.001] at days 10–12 versus 8.57 pmol/L [2.21–9.08] in controls; median [interquartile range, p value using Mann−Whitney U test]).