RESUMEN
BACKGROUND AND PURPOSE: Perianeurysmal edema is rare and is associated with expansion of intracranial aneurysms despite adequate endovascular treatment. The natural history of this condition is poorly understood. We present a case series of perianeurysmal edema to investigate the incidence, natural history and management of these aneurysms. MATERIALS AND METHODS: Retrospective analysis of endovascularly treated aneurysms from January 2001 to December 2012 was performed. Perianeurysmal edema either pre- or post-treatment as detected on MRI was used to identify cases. RESULTS: Ten of the 838 patients demonstrated perianeurysmal edema. The median age was 51.5 (interquartile range 48 to 59). Of the 10 subjects, 50% (5/10) were male. Perianeurysmal edema was detected after the initial presentation and treatment in 70% (7/10) of the patients, with one patient developing headache after endovascular coiling, while the remaining 6 were found on routine follow-up imaging. Only 4 of the patients were ever symptomatic in the setting of perianeurysmal edema, with 3 of these patients improved clinically following treatment of the aneurysm. Radiological follow-up showed expanding neck remnants leading to a second endovascular coiling procedure in 50% (5/10) of the patients and a third procedure in 20% (2/10) of the patients to attenuate aneurysm growth. CONCLUSION: Ten of the aneurysms treated with endovascular therapy in our case series demonstrated perianeurysmal edema. They are mostly asymptomatic, with no cases of re-bleeding identified, however perianeurysmal edema is associated with aneurysm re-expansion despite initial endovascular treatment.