Detection Of The Hemodynamic Parameters In The Operation And The Vascular Bioresearch In The Haemorrhage Factors Of Brain Arteriovenous Malformations

Arteriovenous malformations(AVMs) are the most common cerebral vascular malformations.With the development of Neuro-Surg and further understanding of the etiology of the cerebral arteriovenous malformations,the importance of AVM is gradually being realized by clinicians.Now,AVM Haemorrhage has become one of the major cerebravascular diseases,directly threatening human lives and health.At present,the AVM keep many unknowns to us in the experimental field.To further explore the pathogenesis of AVM and the potential for the optimal treatments for the disease,the research has been carried out through the study of hemodynamic parameters and biological characters of the AVM.PartⅠ.Detection of the Hemodynamie Parameters in the Operation of Brain Arteriovenous malformations1.Detection of the Hemodynamic Parameters by lntraoperative Ultrasound in the Surgical Treatment of Intracranial Arteriovenous malformationsObjective This study was to measure the hemodynamic parameters by intraoperative real-time ultrasound during surgery of cerebral arteriovenous malformations(AVMs).Methods 26 patients with cerebral AVMs underwent microsurgical treatment.An Aloka SSD4000 ultrasound system equipped with a intraoperative probe was used.We measured the velocity of systolic phase(S),velocity of diastolic phase (D),and calculated the mean glow velocity(MVF),the resistance index(RI),the compliance index(S/D).After get the results,RI of AVM was compared with the normal brain feeding artery.Results S was 50～430 cm/s,mean 163 cm/s;Dwas 10～140cm/s,mean 24 cm / s;RI was 0.20～0.54,mean 0.31±0.05;S/D was 1.4～2.5,mean 1.7±0.05。RI of the normal brain feeding artery was 0.60±0.05.Conclusion Intraoperative real—time ultrasound could provide accurate hemodynamic parameters of the cerebral AVMs and provides valuable help for the clinical decision.RI was obvious different between the AVM feeding artery and the normal brain feeding artery.2.The Guidance of Intraoperative Ultrasound in the Surgical Treatment of Intracranial ArteriovenousObjective To investigate the value of intraoperative real-time ultrasound during surgery of cerebral arteriovenous malformations(AVMs).Methods 26 patients with cerebral AVMs underwent microsurgical treatment,an Aloka SSD4000 ultrasound system equipped with a intraoperative probe was used.Imaging was performed before the starting of resection in order to localize and delineate the AVM;definite the hematoma and AVM relationship and identify the feeding arteries and draining veins.After removal of the lesion,sonographic examination was repeated to detect the residual AVM tissue and the findings were compared with post—operative angiographic finding.Results Total resection was achieved in all 26 patients under real-time ultrasonographic examination.The AVM were localized and defined precisely.The hematoma exhibited hyperechogenicity without blood signals.The feeding vessels were distinguished from normal ones hemodynamically.Complete removal of the AVM determined sonographically was then confirmed by angiography. Conclusions Intraoperative real—time ultrasound allows accurate localization of the cerebral AVMs and helps determine the degree of removal of the cerebral AVM.It provides valuable supplement information for pro—operative MRI and DSA during surgery,PartⅡ.Vascular Bioresearch in the Haemorrhage Factors of Brain Arteriovenous malformations1.The Relationship between Haemorrhage and the Expression Variation of VEGF in Brain Arteriovenous MalformationsPurpose:To study the correlation between the expression of vascular endothelial growth factor(VEGF) in cerebral arteriovenous malformations(AVM) and clinical characteristics and to provide clues of AVM haemorrhage and basis for treatment and prognosis.Methods:By fluorescent quantitation PCR method,we determin the VEGF,VEGF receptor " Flt—1 and Flk—1/KDR gene expression of 23 brain AVMs(11 hemorrhaged cases,12 unhemorrhaged cases) and 8 normal blood vessels.By immunohistochemistry method,VEGF protein was analysis.All the results were compared with normal vessel.Results:The VEGF gene expression of hemorrhaged cases was higher than that of the unhemorrhaged cases or normal blood vessels.The VEGF gene expression of the unhemorrhaged cases was higher than that of normal blood vessels.The Flt—1(VEGF receptor 1)gene expression of hemorrhaged cases,unhemorrhaged cases and normal cases was no significant deviation.The Flk—1/KDR(VEGF receptor 2)gene expression of hemorrhaged cases was higher than that of the unhemorrhaged cases and the unhemorrhaged cases was higher than that of normal blood vessels.VEGF protein was seen in 23 brain AVMs by immunohistochemistry method.There was no VEGF protein detected in normal vessel.Conclusions:The increased levels of VEGF gene and protein expression may be the result of AVM hemodynamics.VEGF and Flk—1/KDR gene high expression in EC of some AVM vessels may be one of major factors for AVM formation,growth,and rupture.2.The Relationship between Haemorrhage and the Expression Variation ofMatrix Metalloproteinase—2,9 in Brain Arteriovenous MalformationsPurpose:To analyze the relationship between haemorrhage and expression variation of Matrix Metalloproteinase—2,9 in brain arteriovenous malformations.Methods:By fluorescent quantitation PCR method,we determin the MMP—2,9 and TIMP—2,1 gene expression of 23 BAVMs(11 hemorrhaged cases,12 unhemorrhaged cases) and 8 normal blood vessels.Results:The MMP—2,9 gene expression of hemorrhaged cases was higher than that of the unhemorrhaged cases or normal blood vessels.The MMP—2,9 gene expression of the unhemorrhaged cases was higher than that of normal blood vessels. TIMP—2,1 gene expression was no difference in three groups.Conclusions:The increased levels of MMP—2,9 gene expression may contribute to vascular instability of BAVMs and maybe one of the hemorrhagic reasons.3.Expression of Osteopontin and its Significance in Brain Arteriovenous Malformations Objective:As a marker gene of synthetic vascular smooth muscles and major chemotactic agent for cellular component of blood vessels,Osteopontin(OPN) is considered to play an important role in several kinds of pathological vascular remodeling process.This research was intended to analyze the expression and its significance of OPN gene and protein in brain arteriovenous malformations compared with normal vessels.Method:By fluorescent quantitation PCR method,we determine the OPN gene expression of 23 brain AVMs(11 hemorrhaged cases,12 unhemorrhaged cases) and 8 normal blood vessels.By immunohistochemistry method,OPN protein was analyzed. All the results were compared with the results of normal blood vessels.Results:The OPN gene expression of hemorrhaged cases and unhemorrhaged cases was higher than that of normal blood vessels.But the difference of hemorrhaged cases and unhemorrhaged cases was no significant deviation.OPN protein expression could be detected in 22 of 23 AVM specimens.The expression was mainly in the venous part of brain AVM,especially in the tortuous vein with irregularly thickened wall.In the arterial part,the expression could sometimes be found in the atherosclerotic-like lesions.There is no OPN protein was seen in normal blood vessels.This may indicate the phenotype switch in vascular smooth muscles.There is no statistically significant difference in the extent of OPN expression between the groups with or without history of hemorrhage.Conclusion:OPN expression can be found in the brain AVM vessels,which means active vascular remodeling of AVM for the haemodynamics reasons.This suggested OPN may play an important role in the vascular remodeling process,but not related to AVM hemorrhage.