%0 Journal Article %A Eimad Shotar %A Marc-Antoine Labeyrie %A Alessandra Biondi %A Stéphane Velasco %A Guillaume Saliou %A Grégoire Boulouis %A Benjamin Daumas-Duport %A Romain Bourcier %A Kevin Janot %A Denis Herbreteau %A Caterina Michelozzi %A Kevin Premat %A Hocine Redjem %A Nicolas Bricout %A Pierre Thouant %A Charles Arteaga %A Laurent Pierot %A Florence Tahon %A Kamel Boubagra %A Leon Ikka %A Emmanuel Chabert %A Stéphanie Lenck %A Alexis Guédon %A Arturo Consoli %A Suzana Saleme %A Federico di Maria %A Jean-Christophe Ferré %A Francois Eugene %A René Anxionnat %A Gaultier Marnat %A Zakaria Guetarni %A Nader-Antoine Sourour %A Didier Dormont %A Frédéric Clarençon %T Non-ischemic cerebral enhancing lesions after intracranial aneurysm endovascular repair: a retrospective French national registry %D 2021 %R 10.1136/neurintsurg-2021-017992 %J Journal of NeuroInterventional Surgery %P neurintsurg-2021-017992 %X 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.Data are available upon reasonable request. %U https://jnis.bmj.com/content/neurintsurg/early/2021/09/20/neurintsurg-2021-017992.full.pdf