Aim: Intracranial atherosclerotic major artery stenosis (IMAS) is associated with a high risk of ischemic stroke. Carotid ultrasound (US) has been widely used to evaluate an individual's atherosclerotic burden, but no information is available on whether the carotid US findings are associated with IMAS progression. The aim of the present study was to identify the associations among traditional risk factors, the duplex carotid US findings and IMAS progression in patients with varying degrees of carotid atherosclerosis.
Methods: All patients who underwent a set of imaging studies (MRI, MRA and carotid US) in our outpatient clinic were screened. A total of 101 patients with a mean age of 75.0±10.6 years, who received the same imaging studies with a mean interval of two years, were studied. In each patient, the extent of stenosis of three arteries (both middle cerebral arteries [MCAs] and the basilar artery [BA]) was classified into five grades. The total score of the three arteries was calculated as the global stenosis score (GSS). The progression of IMAS was defined as worsening of stenosis by ≥1 grade on final MRA. The maximum IMT (maxIMT), plaque findings and carotid stenosis were measured by carotid US. A multivariate stepwise logistic regression analysis was used to identify independent predictors of IMAS progression.
Results: Follow-up MRA revealed IMAS progression in 12 patients (11.9%). The logistic regression analysis demonstrated that the baseline GSS (p=0.008) and carotid stenosis ≥70% on the baseline carotid US (p=0.023) were significantly associated with IMAS progression.
Conclusions: The baseline severity of intracranial and extracranial atherosclerosis was significantly associated with the progression of IMAS.