Asymmetrical Gadolinium Leakage in Ocular Structures in Stroke Due to Internal Carotid Artery Stenosis or Occlusion.

PURPOSE: Gadolinium leakage in ocular structures (GLOS) on fluid-attenuated inversion recovery images (FLAIR) is a novel imaging marker in acute ischemic stroke. The present study sought to investigate the frequency and pattern of blood-retina barrier impairment in acute ischemic stroke due to internal carotid artery (ICA) stenosis or occlusion as demonstrated by GLOS.

METHODS: From a magnetic resonance imaging (MRI) report database patients were identified with acute ischemic stroke due to ICA stenosis/occlusion who underwent repeated MRI with intravenous contrast agent administration and FLAIR and MR angiography (MRA). On FLAIR the presence of GLOS was noted in the vitreous body.

RESULTS: Overall 51 patients with a median age of 70 years (interquartile range, IQR 63-77 years) were included. Of these, 22 (43.1%) patients had an ICA stenosis and 29 (56.9%) an ICA occlusion. On contrast-enhanced FLAIR, GLOS was observed in 29 (56.9%) patients: in 7 (13.7%) unilateral, in 15 (68.2%) bilateral asymmetrical and in 7 (31.8%) bilateral symmetrical. In unilateral asymmetrical GLOS, more pronounced enhancement was always found ipsilateral to ICA stenosis/occlusion. In 4 (5.9%) patients with asymmetrical GLOS a pre-existing signal increase in the vitreous body was found on native FLAIR. The presence of GLOS was associated with an impaired collateralization through the circle of Willis (p < 0.001) and external carotid artery branches (p = 0.03).

CONCLUSION: In patients with ischemic stroke due to ICA stenosis/occlusion, GLOS is frequent, commonly unilateral or bilateral asymmetrical, and in some patients associated with pre-existing ocular signal abnormalities. An insufficient collateralization may contribute to the development of unilateral/asymmetrical GLOS.