Non-ischemic cerebral enhancing lesions after intracranial aneurysm endovascular repair: a retrospective French national registry
Eimad Shotar, Marc‐Antoine Labeyrie, Alessandra Biondi, Stéphane Velasco, Guillaume Saliou, Grégoire Boulouis, Benjamin Daumas-Duport, Romain Bourcier, Kévin Janot, Denis Herbreteau, Caterina Michelozzi, Kévin Premat, Hocine Redjem, Nicolas Bricout, Pierre Thouant, Charles Artéaga, Laurent Pierot, F. Tahon, Kamel Boubagra, Léon Ikka, Emmanuel Chabert, Stéphanie Lenck, Alexis Guédon, Arturo Consoli, Suzana Saleme, Federico Di Maria, Jean‐Christophe Ferré, François Eugène, René Anxionnat, Gaultier Marnat, Zakaria Guetarni, Nader Sourour, Didier Dormont, Frédéric Clarençon
Abstract
BACKGROUND: Non-ischemic cerebral enhancing (NICE) lesions are exceptionally rare following aneurysm endovascular therapy (EVT). OBJECTIVE: To investigate the presenting features and longitudinal follow-up of patients with NICE lesions following aneurysm EVT. METHODS: Patients included in a retrospective national multicentre inception cohort were analysed. NICE lesions were defined, using MRI, as delayed onset punctate, nodular or annular foci enhancements with peri-lesion edema, distributed in the vascular territory of the aneurysm EVT, with no other confounding disease. RESULTS: From a pool of 58 815 aneurysm endovascular treatment procedures during the study sampling period (2006-2019), 21/37 centres identified 31 patients with 32 aneurysms of the anterior circulation who developed NICE lesions (mean age 45±10 years). Mean delay to diagnosis was 5±9 months, with onset occurring a month or less after the index EVT procedure in 10 out of 31 patients (32%). NICE lesions were symptomatic at time of onset in 23 of 31 patients (74%). After a mean follow-up of 25±26 months, 25 patients (81%) were asymptomatic or minimally symptomatic without disability (modified Rankin Scale (mRS) score 0-1) at last follow-up while 4 (13%) presented with mild disability (mRS score 2). Clinical follow-up data were unavailable for two patients. Follow-up MRI (available in 27 patients; mean time interval after onset of 22±22 months) demonstrated persistent enhancement in 71% of cases. CONCLUSIONS: The clinical spectrum of NICE lesions following aneurysm EVT therapy spans a wide range of neurological symptoms. Clinical course is most commonly benign, although persistent long-term enhancement is frequent.