2019 年 47 巻 4 号 p. 231-235
Treatment for recurrent intracranial aneurysms previously treated with endovascular coiling remains challenging, and an optimal strategy remains to be established. Nine recurrent cases of previously coiled aneurysms were treated with surgical clipping at our institution. Based on the preoperative digital subtraction angiography finding, the remnant volume (Vremnant) and coil mass volume (Vcoil) of each recurrent aneurysm were calculated to assess aneurysmal collapsibility. Three aneurysms were clipped on the coil mass, and the remaining 6 aneurysms were clipped below the aneurysmal neck. All 9 aneurysms were surgically treated with standard clipping. The mean (95% confidence interval) Vcoil/Vremnant ratio was 0.27 (0.18-0.36), suggesting that the aneurysms with <36% of the coil mass volume relative to the remnant volume were safely clipped. Clipping is still an important treatment option for recurrent coiled aneurysms if the patients are younger or found unsuitable for the endovascular approach, although preoperative angiographic examination regarding aneurysmal collapsibility should be evaluated.