Blood-ocular barrier disruption in patients with acute stroke

Prompted by the unexpected finding of gadolinium leakage into ocular structures (GLOS) in acute stroke patients, we studied the frequency and nature of this finding in 167 patients.

Patients were selected who had an MRI with gadolinium at baseline and another MRI with fluid-attenuated inversion recovery (FLAIR) imaging at 2 and/or 24 hours later. GLOS was detected as lack of vitreous and/or aqueous fluid suppression on postcontrast FLAIR images.

GLOS, evident on postcontrast FLAIR MRI, occurred in 127/167 (76%) patients: 86/109 (79%) patients treated with tissue plasminogen activator and 41/58 (71%) who were untreated. At 2 hours after administration of the contrast, GLOS was more common in the aqueous chamber alone, occurring in 67% of patients, compared to the vitreous chamber alone, seen in 6% of patients; it occurred in both chambers in 27% of patients. At 24 hours, GLOS was present in 121/162 (75%) patients, always involving the vitreous chamber, but also affecting the aqueous chamber in 6% of cases. Vitreous GLOS at 24 hours was associated with increasing age (p = 0.002) and a higher burden of cerebral white matter hyperintensities (p = 0.017). Patients with rapid diffuse GLOS, defined as GLOS involving both chambers at 2 hours, had larger infarcts (p = 0.022) and a higher degree of blood-brain barrier permeability (p = 0.025).

We found GLOS to be common in patients with acute stroke; delayed GLOS was a marker for chronic vascular disease. The mechanism for acute GLOS remains uncertain but may be a remote effect of acute cerebral injury on the blood-ocular barrier.