Investigation of ischemic and demyelinating lesions by cerebral vasoreactivity based on transcranial Doppler sonography: a comparative study

Purpose: Variations of cerebral blood flow in response to hypoxia and hyperoxia in different disease conditions can provide new insights into disease etiopathogenesis. This study aimed to determine the characteristics of cerebral vasoreactivity for ischemia and demyelination. Materials and methods: This case-control study included: 28 patients with lacunar infarctions verified by history, physical examination, and MRI; 28 age-and sex-matched healthy controls; 28 patients with relapsing-remitting multiple sclerosis (MS), based on McDonald criteria; and 28 age- and sex-matched healthy controls for the MS group. Transcranial Doppler sonography was undertaken in all subjects to calculate the mean flow velocity (MFV) of the right middle cerebral artery (MCA) and, after a breath-holding (BH) maneuver, the breath-holding index (BHI) was determined. Results: There was no significant difference of BHI and changes of MFV of the MCA in MS patients compared to controls (1.02 +/- 0.4 vs 1.02 +/- 0.3, p = 0.993; and 16.8 +/- 8.1 vs 11.3 +/- 10.8, p = 0.057). BHI in patients with lacunar infarctions was significantly lower (0.8 +/- 0.4 vs 1.2 +/- 0.3, p < 0.001) compared to controls. The BHI (p = 0.040) and variations of MFV of MCA (p = 0.007) in MS patients were significantly higher than in patients with lacunar infarctions. The vasoreactivity of demyelinating lesions was higher than that of ischemic ones. Conclusion: Therefore, cerebral vasoreactivity determined by transcranial Doppler could be utilized for differentiating demyelinating from ischemic lesions.