The Study Of The Relationship Between Cerebral Autoregulation And Neuroimaging Characteristics Of Cerebral Small Vessel Disease

Objective:Cerebral small vessel disease(CSVD)is a term that generally refers to a syndrome of clinical,cognitive,neuroimaging and pathological findings caused by functional and structural changes of small arteries,arterioles,venules,and capillaries and the resulting brain damage.It is very common and has been reported to be associated with cognitive decline,depression,and physical disabilities in the elderly.The neuroimaging manifestations include recent small subcortical lacunar infarct,lacune,white matter hyperintensity(WMH),cerebral microbleed(CMB),perivascular space(PVS)and brain atrophy.Cerebral autoregulation(CA)refers to the process in which cerebral blood flow is relatively stable through contraction and relaxation of cerebral vessels when cerebral perfusion pressure changes.Dynamic cerebral autoregulation(dCA)reflects the instant response of cerebral blood flow when blood pressure changes.The purpose of this study is to discuss the relationship between dCA and neuroimaging characteristics of CSVD,and to explore possible pathogenesis and potential therapeutic targets.Methods:This study was performed at the Comprehensive Stroke Center,Department of Neurology,First Hospital of Jilin University from December 2016 to October 2020,and a total of 112 CSVD patients were involved.83 age-and sex-matched healthy volunteers were also obtained as the control group.Neuroimaging characteristics of CSVD patients were evaluated.Transcranial Doppler ultrasound(TCD)was used to monitor the cerebral blood flow velocity(CBFV)of bilateral middle cerebral artery(MCA)and a servo-controlled plethysmograph was used to record spontaneous arterial blood pressure.Transfer function analysis(TFA)was used to calculate dCA parameters: phase,gain and correlation.The rate of recovery(RORc)of CBFV was also included to evaluate the dCA function of patients with CSVD.The relationship between dCA and neuroimaging characteristics of CSVD was statistically analyzed.Results:Compared with the control group,the RORc of CBFV and the phase at low frequency in patients with CSVD were significantly decreased(P < 0.001),and the gain at very low frequency and low frequency were significantly increased(P < 0.001),suggesting impaired dCA in patients with CSVD;in multivariate linear regression analyses,phase at low frequency had negative associations with the severity of total WMH(β =-2.495,P = 0.002),periventricular WMH(β =-4.369,P = 0.005),deep WMH(β =-4.515,P = 0.002),lobar CMBs(β =-7.428,P = 0.017)and PVS(β =-11.127,P = 0.039)and the total burden of CSVD(β =-3.387,P = 0.009).Conclusions:DCA was impaired bilaterally in patients with CSVD and there was a negative correlation between the severity of CSVD and dCA function.This study confirmed the role of cerebral small vessels in CA and proposed that CA measurement could be used as an effective method to evaluate the function of cerebral small vessels.