Risk factors of postoperative cerebral hyperperfusion syndrome and its relationship with clinical prognosis in adult patients with moyamoya disease

Background To investigate the incidence,risk factors,and clinical prognosis of cerebral hyperperfusion syndrome(CHS)after superficial temporal artery-middle cerebral artery anastomosis combined with encephalo-duro-arterio-synangiosis(STA-MCA/EDAS)in adult patients with moyamoya disease(MMD).Methods The clinical data of 160 adult patients with MMD treated by STA-MCA/EDAS from January 2016 to January 2017 were retrospectively analyzed.According to CHS diagnosis,MMD patients were divided into CHS and non-CHS group.Univariate and multivariate analysis of risk factors and Kaplan-Meier curve of stroke-free survival for CHS were performed.Results A total of 12 patients(7.5%)developed postoperative CHS,of which 4 patients(2.5%)presented with cerebral hemorrhage.Univariate and multivariate analysis showed moyamoya vessel on the surgical hemisphere(OR=3.04,95%CI=1.02-9.03,P=0.046)and left operated hemisphere(OR=5.16,95%CI=1.09-21.34,P=0.041)were independent risk factors for CHS.The other variables,such as age,gender,presentation,hypertension,diabetes,smoking,mean mRS score on admission,modified Suzuki stage and pre-infarction stage on surgical hemisphere,and bypass patency,had no association with postoperative CHS(P>0.05).At final follow-up with average 38 months,there were 18 out of 133 patients(13.5%,4.91%per person year)presented with newly developed complications.There was no significant difference between newly developed complications,mean mRS scores,and Kaplan-Meier curve of stroke-free survival in patients with and without CHS(P>0.05).Conclusion The concentration of moyamoya vessels and left operated hemisphere was independent risk factors for CHS,which could not affect the clinical prognosis if treated timely and properly.The current study offers a new perspective of moyamoya vessels and supporting data for choosing MMD candidates on cerebral revascularization.

Prediction of Cerebral Hyperperfusion Syndrome with Velocity Blood Pressure Index

Background：Cerebral hyperperfusion syndrome is an important complication of carotid endarterectomy （CEA）.An 〉 100% increase in middle cerebral artery velocity （MCAV） after CEA is used to predict the cerebral hyperperfusion syndrome （CHS） development,but the accuracy is limited.The increase in blood pressure （BP） after surgery is a risk factor of CHS,but no study uses it to predict CHS.This study was to create a more precise parameter for prediction of CHS by combined the increase of MCAV and BP after CEA.Methods：Systolic MCAV measured by transcranial Doppler and systematic BP were recorded preoperatively;30 min postoperatively.The new parameter velocity BP index （VBI） was calculated from the postoperative increase ratios of MCAV and BE The prediction powers of VBI and the increase ratio of MCAV （velocity ratio [VR]） were compared for predicting CHS occurrence.Results：Totally,6/185 cases suffered CHS.The best-fit cut-off point of 2.0 for VBI was identified,which had 83.3% sensitivity,98.3% specificity,62.5% positive predictive value and 99.4% negative predictive value for CHS development.This result is significantly better than VR （33.3%,97.2%,28.6% and 97.8%）.The area under the curve （AUC） of receiver operating characteristic：AUCvBI =0.981,95% confidence interval [CI] 0.949-0.995;AUCvR =0.935,95% CI 0.890-0.966,P =0.02.Conclusions：The new parameter VBI can more accurately predict patients at risk of CHS after CEA.This observation needs to be validated by larger studies.

Gastroduodenal artery disconnection during liver transplantation decreases non-anastomotic stricture incidence

Background:The hepatic artery is the only blood source nourishing the biliary duct and associated with biliary complication after liver transplantation(LT).Gastroduodenal artery(GDA)disconnection increased proper hepatic artery flow.Whether this procedure attenuates biliary non-anastomotic stricture(NAS)is not clear.Methods:A total of 241 patients with LT were retrospectively analyzed.The patients were divided into the GDA disconnection(GDA-)and GDA preservation(GDA+)groups.Propensity score matching(PSM)was administrated to reduce bias.Logistic regression was conducted to analyze risk factors for biliary NAS before and after PSM.Postoperative complications were compared.Kaplan-Meier survival analysis and log-rank tests were performed to compare overall survival.Results:In all,99 patients(41.1%)underwent GDA disconnection,and 49(20.3%)developed NAS.Multivariate logistic regression revealed that GDA preservation(OR=2.24,95%CI:1.11-4.53;P=0.025)and model for end-stage liver disease(MELD)score>15(OR=2.14,95%CI:1.12-4.11;P=0.022)were risk factors for biliary NAS.PSM provided 66 pairs using 1:2 matching method,including 66 GDA disconnection and 99 GDA preservation patients.Multivariate logistic regression after PSM also showed that GDA preservation(OR=3.15,95%CI:1.26-7.89;P=0.014)and MELD score>15(OR=2.41,95%CI:1.08-5.36;P=0.031)were risk factors for NAS.When comparing complications between the two groups,GDA preservation was associated with a higher incidence of biliary NAS before and after PSM(P=0.031 and 0.017,respectively).In contrast,other complications including early allograft dysfunction(P=0.620),small-for-size graft syndrome(P=0.441),abdominal hemorrhage(P=1.000),major complications(Clavien-Dindo grade≥3,P=0.318),and overall survival(P=0.088)were not significantly different between the two groups.Conclusions:GDA disconnection during LT ameliorates biliary NAS incidence and may be recommended for application in clinical practice.

Split liver transplantation:What's unique?

The intraoperative management of split liver transplantation(SLT) has some unique features as compared to routine whole liver transplantations. Only the liver has this special ability to regenerate that confers benefits in survival and quality of life for two instead of one by splitting livers. Primary graft dysfunction may result from small for size syndrome. Graft weight to recipient body weight ratio is significant for both trisegmental and hemiliver grafts. Intraoperative surgical techniques aim to reduce portal hyperperfusion and decrease venous portal pressure. Ischemic preconditioning can be instituted to protect against ischemic reperfusion injury which impacts graft regeneration. Advancement of the technique of SLT is essential as use of split cadaveric grafts expands the donor pool and potentially has an excellent future.