Background: Giant intracranial aneurysms (GIAs), which are defined as intracranial aneurysms (IAs) with a diameter of ≥25 mm, are most likely associated with the highest treatment costs of all IAs. However, the treatment costs of unruptured GIAs have so far not been reported.

Objective: To examine direct costs of endovascular and surgical treatment of unruptured GIAs.

Methods: We retrospectively examined 55 patients with unruptured GIAs treated surgically (37 patients) or endovascularly (18 patients) between April 2004 and March 2014. We analyzed the costs of all hospital stays, interventions, and imaging with a median follow-up of 46 months.

Results: There was no difference in the costs of hospital stay between surgical and endovascular treatment groups ($10,565 vs. $14,992; P = .37). Imaging costs were significantly higher in the surgical group than in the endovascular treatment group ($2890 vs. $1612; P < .01), as were the costs of the intervention room and personnel involved in the intervention ($5566 vs. $1520; P < .01). Implants used per patient were more expensive in the endovascular group than in the surgical treatment group ($20,885 vs. $167). The total direct treatment costs were higher in the endovascular group ($52,325) than in the surgical treatment group ($20,619; P < .01). Treatment costs were associated with the type of treatment and GIA location but not with patient age, sex, or GIA size.

Conclusion: Endovascular GIA treatment produced higher direct costs than surgical GIA treatment mainly due to higher implant costs. Reducing endovascular implant costs may be the most effective tool to decrease direct costs of GIA treatment.