Surgical technique and nuances in ruptured versus unruptured arteriovenous malformation surgery.

Because of the more frequent use of noninvasive imaging methods, arteriovenous malformation (AVM) are gaining more attention. Population based studies reveal that about 35% to 50% of patients with AVM initially present with hemorrhage. Prior hemorrhage is the most consistent risk factor for future hemorrhage, other risk factors include deep venous drainage pattern, deep location, and so on. Surgical interventions, including surgical excision, intravascular intervention, and stereotactic radiation, have been developed with the aim to eliminate this source of hemorrhage. Among these methods, surgical excision was considered to be the gold standard for low grade intracranial AVMs. In ruptured AVMs, it is standard to wait several weeks to allow for patient recovery, hematoma liquefaction, and inflammatory reactions to subside, except for the life threatening hemorrhage. By separating the nidus from adjacent brain (the combined effects of the hematoma cavity and encephalomalacia), the hematoma creates a space for operator and facilitates AVM resection actually. There are some surgical nuances in ruptured versus unruptured AVM surgery. Detailed preoperative preparation is necessary to evaluate the general situation, neurological status, AVM architecture characteristic before surgery. Essential assistant technique, reasonable strategy and meticulous operative skill are crucial for the safety and validity of AVM resection.