Objective: To determine the clinical value of cerebrovascular hemodynamics analysis (CVA) on cerebral microcirculation.
Methods: One hundred consecutive patients from neurological department of Peking University People's Hospital from April to October, 2015, with symptoms of dizziness, lightheadedness, headache etc., who were diagnosed with ischemic cerebrovascular disease with normal transcranial doppler (TCD) and abnormal CVA, were recruited in this study.Other medical conditions were excluded through clinic and imaging examinations among these patients.Patients were categorized into mild, moderate and severe subgroups based on the degrees of decreased blood flow velocity and/or volume, and received treatment accordingly.CVA parameters including the minimum flow velocity (Vmin), the minimum flow volume (Qmin), peripheral resistance (R), critical pressure (CCP) and dynamic resistance (CVR) etc.before and after treatment were compared statistically (t test).
Results: Out of the 100 patients with abnormal CVA, 52 patients had bilateral changes and 48 patients had unilateral changes.The minimum flow velocity and the minimum flow volume anomalies were found in 100 and 92 cases, respectively.A total of 47, 32 and 21 patients had mild, moderate and severe abnormal changes, respectively.Out of the 63 patients who had follow-up CVA after treatment (drop-out 37 cases), there were 63 abnormal Vmin cases, 60 abnormal Qmin cases, 17 abnormal R cases, 18 abnormal CCP cases, 41 abnormal characteristic impedance (Zc) cases, 41 abnormal elastic wave velocity (Wv) cases, 23 abnormal vascular compliance (C) cases, all before treatment.After treatment, symptoms and Vmin synchronization improved in 61 cases (96.8%), Qmin improved in 58 cases (96.6%), R improved in 13 cases (76.5%), CCP improved in 10 cases (55.6%), Zc improved in 27 cases (65.8%), Wv improved in 25 cases (61.0%), C improved in 6 cases (26.1%). All improvements were statistically significant (P<0.05), with Vmin, Qmin, R and CCP showing most significant changes (P<0.000 1). The CVR treatment showed no significant before and after treatment (P>0.05).
Conclusions: CVA is an important method in assessing cerebral microcirculation perfusion, providing information on intracranial microvascular bed that cannot be detected by TCD.It is not only helpful for diagnosis, but also evaluable for monitoring clinical treatment of cerebral microcirculation disorder.CVA is also helpful in determining the location of cerebral circulation impairment by correlation with carotid ultrasound and TCD.