Treatment and diagnosis of cerebral aneurysms in the post-International Subarachnoid Aneurysm Trial (ISAT) era: trends and outcomes

Background Following publication of the International Subarachnoid Aneurysm Trial (ISAT), treatment paradigms for cerebral aneurysms (CAs) shifted from open surgical clipping to endovascular embolization as primary therapy in a majority of cases. However, comprehensive analyses evaluating more recent CA diagnosis patterns, patient populations and outcomes as a function of treatment modality remain rare. Methods The National Inpatient Sample from 2004 to 2014 was reviewed. Aneurysmal subarachnoid hemorrhages (aSAHs) and unruptured intracranial aneurysms (UIAs) with a treatment of surgical clipping or endovascular therapy (EVT) were identified. Time trend series plots were created. Linear and logistic regressions were utilized to quantify treatment changes. Results 114 137 aSAHs and 122 916 UIAs were reviewed. aSAH (+732/year, p=0.014) and UIA (+2550/year, p Conclusion Ruptured and unruptured CAs are increasingly being treated with EVT over clipping. Incidental unruptured aneurysm diagnoses are increasing dramatically. Mortality rates of ruptured aneurysms are improving regardless of treatment modality, whereas mortality in unruptured aneurysms is only improving for surgical clipping.