Introduction: Enhancing intracranial atherosclerotic plaque on high-resolution vessel wall MRI (vwMRI) is a reliable marker of recent thromboembolism, and confers a recurrent stroke risk of up to 30% a year. Post-contrast plaque enhancement (PPE) on vwMRI is thought to represent inflammation, but studies have not fully examined the clinical, serologic or radiologic factors that contribute to PPE.
Methods: Inpatients with acute ischemic stroke due to intracranial atherosclerosis were prospectively enrolled at a single center from 2015-16. vwMRI was performed on a 3T Siemens Verio and included 3D DANTE pulse sequences, pre- and post-contrast (for PPE identification). Three experienced neuroradiologists interpreted vwMRI using a validated multicontrast technique. The Chi-squared, Fisher’s Exact, and Student’s t-test were used for intergroup differences, and logistic regression was fitted to the primary outcome of PPE.
Results: Inclusion criteria were met by 35 patients. Atherosclerotic plaques were in the anterior circulation in 21/35 (60%) and PPE was diagnosed in 20/35 (57%) of stroke parent arteries. PPE predictors are shown in Table 1 with logistic regression in Table 2.
Conclusion: PPE is associated with stenosis, which was expected, but the association with HgbA1c is novel. All patients with HgbA1c >8 had PPE and a one point HgbA1c rise increased the odds of PPE 3-fold. Hyperglycemia induces vascular oxidative stress by generating reactive oxygen species, quenching nitric oxide, and triggering an inflammatory cascade. Given the high rate of stroke recurrence in PPE patients, aggressive HgbA1c reduction may be a viable treatment target and warrants additional study.