Longitudinal radiological follow-up of individual level non-ischemic cerebral enhancing lesions following endovascular aneurysm treatment

J Neurointerv Surg. 2024 Jul 16;16(8):838-845. doi: 10.1136/jnis-2023-020060.


Background: Non-ischemic cerebral enhancing (NICE) lesions following aneurysm endovascular therapy are exceptionally rare, with unknown longitudinal evolution.

Objective: To evaluate the radiological behavior of individual NICE lesions over time.

Methods: Patients included in a retrospective national multicentric inception cohort were analyzed. 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 treatment, with no other confounding disease. Lesion burden and the longitudinal behavior of individual lesions were assessed.

Results: Twenty-two patients were included, with a median initial lesion burden of 36 (IQR 17-54) on the first MRI scan. Of the 22 patients with at least one follow-up MRI scan, 16 (73%) had new lesions occurring mainly within the first 200 weeks after the date of the procedure. The median number of new lesions per MRI was 6 (IQR 2-16). Among the same 22 patients, 7 (32%) had recurrent lesions. The median persistent enhancement of a NICE lesion was 13 weeks (IQR 6-30). No factor was predictive of early regression of enhancement activity with lesion regression kinetics mainly being patient-dependent.

Conclusions: The behavior of individual NICE lesions was found to be highly variable with an overall patient-dependent regression velocity.

Keywords: Aneurysm; Complication; Inflammatory Response.

Publication types

  • Multicenter Study

MeSH terms

  • Aged
  • Endovascular Procedures* / adverse effects
  • Endovascular Procedures* / methods
  • Female
  • Follow-Up Studies
  • Humans
  • Intracranial Aneurysm* / diagnostic imaging
  • Intracranial Aneurysm* / surgery
  • Longitudinal Studies
  • Magnetic Resonance Imaging*
  • Male
  • Middle Aged
  • Retrospective Studies