Editorial. FIAT, flow diverters, and establishing the role of new technology

Abstract

D espite significant advances in the microsurgical and endovascular management of aneurysms, there continue to be lesions for which the ideal treatment option remains controversial. This group of aneurysms includes those that arise from the proximal intracranial carotid, many posterior circulation aneurysms, dissecting pseudoaneurysms, and dysplastic wide-necked aneurysms that incorporate the parent vessel. Flow diversion devices have been introduced as a means to address these aneurysms, which would otherwise require advanced skull base techniques, possible bypass and vessel sacrifice, or endovascular management beyond simple coiling. The authors have executed a randomized care trial (Flow Diversion in the Treatment of Intracranial Aneurysm Trial [FIAT]) to examine the safety and efficacy of flow diversion compared with the more traditional means of aneurysm treatment. 5 The study was halted due to safety concerns as a significantly greater number of patients randomized to flow diversion were dead or dependent at 3 or more months. Efficacy, measured by angiographic obliteration, was also below the expectations put in place in the trial hypothesis. As a result, the authors have provided important data that clinicians must take into consideration when addressing these difficult lesions. Based on the results of the trial, the authors conclude that flow diversion proved to not be as safe and effective as they originally hypothesized. The authors eloquently discuss the limitations of the study and the significant challenges facing the future study of flow diversion devices. Clearly, additional investigation is needed to better understand the role of flow diversion in the management of cerebral aneurysms. Perhaps this statement is the strongest conclusion that is to be taken from this paper. However, there are significant barriers that will have to be overcome to gain meaningful data in further studies. First, the grouping of aneurysms under a catchall term ©AANS, 2017

The 2018 ter Brugge Lecture: Problems with the Introduction of Innovations in Neurovascular Care

“…2 Then we observed our unvalidated practices with the new device using epidemiological methods, 3 instead of performing the randomized trials appropriate for the care of patients facing uncertain management choices. [4][5][6][7] For example, pre-clinical research consists of testing a new device/technique on an animal model, as a preliminary step to understand the mechanisms of failure or success. Investigators then try to control all parameters that could interfere with the observation of the phenomenon of interest [animals are selected to be as similar as possible (i.e., same genetic lineage)].…”