avm_动静脉畸形(ppt).pptVIP

What to do? Arteriovenous malformation of the brain Diagnosis and treatment Development 3rd week of pregnancy primitive vessels do not develop into normal vasculature formation of an arteriovenous shunt Symptoms Hemorrhage history of sudden headache age usually 25 – 35 years hemorrhage less severe than SAH no vasospasm risk 2 – 3 % per year Seizures often focal, but may generalize often better after operation Neurological deficit due to ischaemia of surrounding brain develops with increasing age especially in large AVM’s Diagnosis history and neurological examination CT-scan MRI and MRA angiography Evaluation size draining veins (deep) arterial feeders localization in brain associated aneurysms define bleeding source Treatment conservative closing of feeder arteries excision endovascular radiotherapy Conservative treatment control of epilepsy control of hypertension life-style advice Closing feeder arteries reduction in blood flow short lived effect collaterals will develop no risk reduction! Excision size localisation number of feeders venous drainage ± 75% can be excised only 100% effective treatment! depends on Endovascular balloon occlusion occlusion of the nidus identify bleeding source only indicated if 100% elimination may be combined with surgical treatment Radiotherapy causes hyperplasia of intima secondary thrombosis for deep-seated AVM’s 3 cm occlusion rate 80% effect after two years life-long follow-up necessary? Operative technique BP 100 mm Hg moderate cooling start on the arterial side! observe natural shape of AVM occlusion of veins as last step keep BP low post op. keep patient sedated 24 – 48 hours Problems oedema seizures perfusion pressure breakthrough re-bleed (only if excision incomplete!) Example #1 Example #2