feasibility of fluorescenceguided resection of recurrent gliomas using fiveaminolevulinic acid retrospective analysis of surgical and neurological outcome in 58 patients fiveaminolevulinicacid 5ala is known for its benefits in surgery of primary gliomas but has only been cautiously used in recurrent gliomas dreading overresection insufficient or falsepositive fluorescence in adjuvantly treated tumors we evaluated intraoperative fluorescence based on tumor pathology pretreatment as well as surgical and neurological outcome in patients with recurrent gliomas patients who underwent fluorescenceguided surgery for recurrent gliomas between 62010 and 22014 at our institution were retrospectively selected degree of surgical resection neurological status pathology results intraoperative fluorescence and follow up status were analyzed patients who underwent repeat surgery without 5ala were selected as controls 58 patients with high grade gliomas iii and iv were included 10 of 63 tumors 159 failed to fluoresce intraoperatively of which nine 90 had been adjuvantly treated prior to recurrence as were 46 of the 53 fluorescing tumors 868 nonfluorescing tumors were idh mutated significantly more often p 0005 30 tumors 476 were located eloquently 51 809 patients showed no new neurologic deficits postoperatively 13 patients 206 showed no signs of recurrence at their latest follow up eight patients were lost to follow up overall survival was significantly longer in the 5ala group p 0025 fluorescenceguided surgery in recurrent gliomas is safe and allows for a good surgical and neurological outcome in a difficult surgical environment especially when used in combination with neuronavigation and intraoperative ultrasound to prevent overresection adjuvant therapy did not significantly influence fluorescing properties