• cerebral aneurysm;
  • coil embolization;
  • bioactive coil;
  • headache;
  • fever

Background.— Based on our encounters with patients who have been treated for unruptured intracranial aneurysms by endovascular coil embolization using bioactive coils, we observed that such patients often present with headaches and fever.

Objective.— The purpose of this study was to evaluate the incidence of headache and fever after coil embolization using bioactive coils.

Methods.— A database of 92 intracranial unruptured aneurysm patients (88 patients who did not have chronic headaches or migraines before treatment) on whom coil embolization had been performed between July 2007 and October 2010 was retrospectively assessed. Forty-five aneurysms (43 patients) were treated using bioactive coils and the other aneurysms were treated using bare coils. We analyzed the incidence and duration of headache, temperature, C-reactive protein, and white blood cell count before and after coil embolization and compared the 2 groups.

Results.— Forty-one patients (46.6%) reported onset of headaches just after treatment. Headache incidences were significantly greater in the patients treated with bioactive coils (bioactive coil group: 62.8% [27/43] vs bare coil group: 31.1% [14/45], P = .003), and the duration of headaches was significantly longer in the bioactive coil group (bioactive coil group: 3.44 ± 1.22 days vs bare coil group: 2.40 ± 1.17 days, P = .027). Seventy-one patients (80.7%) had incidences of fever (over 37°C) after treatment (bioactive coil group: 83.7% [36/43] vs bare coil group: 77.8% [35/45], P = .663). The duration of fever was significantly longer in the bioactive coil group (bioactive coil group: 2.9 ± 1.4 days vs bare coil group: 1.9 ± 1.1 days, P = .0017), and temperatures at 1, 2, or 3 days after treatment were significantly higher in the bioactive coil group (respective temperatures at 1, 2, 3 days after treatment: bioactive coil group: 37.42 ± 0.49, 37.19 ± 0.45, 37.00 ± 0.49 vs bare coil group: 37.14 ± 0.38, 36.96 ± 0.41, 36.63 ± 0.51, P = .009, P = .0246, P = .0032). There were no significant differences in C-reactive protein level and white blood cell count 1 and 3 days after treatment between 2 groups.

Conclusions.— Bioactive coils induce headache and fever after coil embolization for intracranial aneurysms due to the inflammatory effects of polyglycolic acid used to accelerate aneurysm fibrosis and neointimal formation.