Monitoring And Treatment Of Cerebral Microvascular Dysfunction After Spontaneous Subarachnoid Hemorrhage

Part 1 Color-coded digital subtraction angiography forevaluation of cerebral microvascular dysfunction afterspontaneous subarachnoid hemorrhageOBJECTIVE: Spontaneous subarachnoid hemorrhage(aSAH)caused by rupture of intracranial aneurysms is often associated with cerebral microvascular dysfunction,which is one of the factors of poor prognosis.We used digital subtraction angiography(DSA)and color-coded parameters post-processing technique to observe the hemodynamic changes of the micro-vessels after aSAH,and investigate the relationship between microvascular injury and outcome.METHODS: This study included patients who were diagnosed with aSAH and received DSA examination within 3 days after hemorrhage at our center from January 1,2016 to December 31,2017.The 2D DSA angiography data were collected and imported into the post-processing workstation.Color-coding software(iFlow software)was used to generate a color-coded blood flow map according to the time-density curve(TDC)of contrast agent.Four regions of interest(ROI)was select on the lateral side of the color-coded blood flow maps: ophthalmic segment of the internal carotid artery,frontal lobe,parietal lobe,and the superior sagittal sinus 2cm above the confluence of sinus,and generate TDC of each ROI.The TDCs were imported into Matlab software and the hemodynamic parameters of each ROI was obtained including time to peak(TPP),maximum peak value(PD),area under curve(AUC).),full width of half maximum(FWHM),maximal slope of wash-in and wash-out(MS-in/MS-out),mean transmit time(MTT)and circulation time(CirT).The correlations between each parameter and Hunt-Hess grade,WFNS grade,and modified Rankin Score(mRS)were analyzed.RESULTS: A total of 119 patients with aSAH were included in the study,including 45 males and 74 females,with an average age of(55.92±10.41)years.There were 2 patients with Hunt-Hess grade I,66 with grade II,25 with grade III,21 with grade IV,and 5 grade V.At the time of discharge,there were 70 patients with mRS 0 point,10 with 1 point,3 with 2 points,4 with 3 points,8 with 4 points,19 with 5 points,and 5 with 6 points.There were no significant differences in the parameters of MS-in,MS-out,FWHM,MTT,TTP,AUC,and PD between the bilateral frontal lobes and the parietal lobes.The TTP,CirT,and FWHM in high Hunt-Hess grade were significantly longer than low Hunt-Hess grade.Linear regression analysis revealed that FWHM and TTP were independent risk factors with poor outcome.Patients with FWHM larger than 2.856 s and TTP larger than 3.465 s are prone to suffer from poor outcome.CONCLUSIONS: FWHM,TTP and CirT are sensitive indicators of the severity of microvascular injury.FWHM and TTP were independent risk factors with poor outcomePart ? C-arm flat-detector CT whole brain perfusionimaging for evaluation of microcirculatory perfusion afteraSAHOBJECTIVE: patients with aSAH often associated with microvascular autoregulation dysfunction and abnormal microcirculatory perfusion in the early stage,leading to poor prognosis.C-arm flat-detector CT(FDCT)whole brain perfusion imaging-parenchymal blood volume(PBV)is a newly developed perfusion method that can be completed with DSA examination.We used PBV perfusion to observe the microcirculatory perfusion changes in the early stage of aSAH for evaluation the microcirculatory injury.METHODS: This study included patients who were diagnosed with aSAH and received endovascular embolization within 3 days after hemorrhage at our center from January 1,2016 to December 31,2017.Before embolization,whole brain perfusion scan was performed.The perfusion data was collected and transmitted to the post-processing workstation.PBV software was used to reconstruct the perfusion data and generate PBV perfusion images.Five ROI was selected: the frontal cortex,occipital cortex and basal ganglia at the lateral ventricular level,frontal cortex and parietal cortex at the semiovale level.Each ROI would generate a PBV value.The relationship between PBV and bleeding degree,prognosis was analyzed.RESULTS: This study included 66 patients with aSAH,including 24 males and 42 females;the average age was(55.98±9.99)years.There were 1 patient with Hunt-Hess grade I,25 with grade II,11 with grade II,20 with grade IV and 9 with grade V.At the time of discharge,there were 28 patients with mRS 0 score,6 with 1 score,3 with 2 scores,4with 3 scores,19 with 5 scores and 1 with 6 scores.PBV values in the occipital lobe and parietal cortex were significantly lower in low Hunt-Hess grade and WFNS grade than high Hunt-Hess grade and WFNS grade.Only the PBV of the parietal lobe was significantly correlated to mRS.The PBV of the parietal lobe in the good outcome group was significantly lower than that in the poor group.The risk of poor prognosis increased by 8.489 times when the PBV of parietal cortex exceeded 35.75.CONCLUSIONS: The higher grade of SAH,the higher the PBV values in the occipital and parietal cortices.PBV values of parietal cortex are statistically correlated with the outcome.The PBV values were significantly lower in the good group than in the poor group.Part ? Dynamic assessment of cerebral microvascularautoregulation function using intracranial pressure monitoring and its application in individualized treatment ofpatients with high-grade aSAHOBJECTIVE: Patients with high-grade aSAH often have impaired cerebral autoregulation(CA)function,aggravating brain injury and worsening the patient's outcome.In this study,we used intracranial pressure(ICP)monitoring to real-time monitoring of the CA function and adopted individualized treatment according to the impairment of CA to investigate the outcome of the high-grade aSAH patients.METHODS: From Jan 2016 to Dec 2017,patients diagnosed with high-grade aSAH were treated with endovascular embolization of the ruptured aneurysm within 24 hours after admission,followed by invasive ventricular ICP monitoring,and arterial pressure monitoring.ICP waves and arterial pressure waves were collected and analyzed through NEUMATIC software to generate cerebral perfusion pressure(CPP),pressure reactivity index(PRx),intracranial pressure amplitude-arterial pressure amplitude index(IAAC),and mean wave amplitude of ICP(MWA)and Correlation coefficient between amplitude and ICP(RAP).By plotting the correlation curves of PRx and CPP over a period of at least 4 hours,the optimal CPP(CPPopt)for ensuring best CA function was obtained and used as the therapeutic CPP target clinically.RESULTS: A total of 36 patients(14 males,22 females;average age: 56.83±11.13 years)with grade IV and V aSAH were included in this study.Four patient died and overall mortality rate was 11.11%.The remaining 32 cases were followed up for at least 6 months.56.3% had good outcomes(mRS 0-3),and 43.7% had poor outcomes(mRS 4-6).The initial ICP in patients with WFNS 5 were significantly higher than that in WFNS 4 patients(P<0.05).Repeated measurements of ICP and CPP did not correlate with prognosis.65% of patients showed PRx>0.2.Initial PRx and ICP variability were independent risk factors for adverse outcomes in patients.CONCLUSIONS: External ventricular drainage combined with ICP monitoring could satisfied control the raised ICP after SAH and may improve the outcome.PRx is an independent risk factor for poor prognosis.PRx-based CPPopt-targeted therapy may alleviate the CA injury and improve the patient's outcome.ICP variability were also independent risk factors for poor outcomes.