ELANA, excimer laser-assisted nonocclusive anastomosis, is a technique using an excimer laser/catheter system for intracranial bypass surgery of the brain. The technique has been developed over the past 12 years by Tulleken and colleagues at UMC Utrecht in The Netherlands for treatment of primarily untreatable giant aneurysms. We review here the emergence of transplanted conduit bypass as a valuable technique for managing these lesions and the subsequent development of ELANA bypass. The ELANA technique allows the operating surgeon to perform an extracranial-to-intracranial or intracranial-tointracranial bypass using a transplanted large caliber conduit without occlusion of the recipient artery, thus eliminating intraoperative ischemic insult related to temporary occlusion time. We describe the ELANA technique, illustrate it with intraoperative photos, and review the relevant literature. ELANA is shown to be safe; we discuss its advantages over conventional techniques.KEYWORDS: Excimer laser-assisted nonocclusive bypass, extracranial-tointracranial bypass, high-flow bypass ELANA, excimer laser-assisted nonocclusive anastomosis, is a technique using an excimer laser/catheter system that has been developed over the past 12 years by Tulleken and colleagues in UMC Utrecht. The technique and system have been designed for the purpose of treating primarily giant or untreatable aneurysms of the intracranial circulation. The ELANA technique allows the operating surgeon to perform an extracranial-tointracranial (EC-IC) or intracranial-to-intracranial Skull Base, volume 15, number 3, 2005. Address for correspondence and reprint requests: