Initial Experience of Coil Embolization for Unruptured Intracranial Aneurysm Combined with Neuroform Atlas and Undersized Flexible Coils

Koji Omoto; Katsutoshi Takayama; Ai Okamoto; Kaoru Myochin; Takeshi Wada; Ichiro Nakagawa; Shinichiro Kurokawa; Hiroyuki Nakase; Kimihiko Kichikawa

doi:10.5797/jnet.oa.2020-0061

Initial Experience of Coil Embolization for Unruptured Intracranial Aneurysm Combined with Neuroform Atlas and Undersized Flexible Coils

J Neuroendovasc Ther. 2021;15(3):135-141. doi: 10.5797/jnet.oa.2020-0061. Epub 2020 Sep 29.

Authors

Koji Omoto¹, Katsutoshi Takayama², Ai Okamoto¹, Kaoru Myochin³, Takeshi Wada², Ichiro Nakagawa⁴, Shinichiro Kurokawa¹, Hiroyuki Nakase⁴, Kimihiko Kichikawa³

Affiliations

¹ Departments of Neurosurgery, Ishinkai Yao General Hospital, Yao, Osaka, Japan.
² Departments of Radiology and Interventional Radiology, Ishinkai Yao General Hospital, Yao, Osaka, Japan.
³ Department of Radiology, Nara Medical University, Kashihara, Nara, Japan.
⁴ Department of Neurosurgery, Nara Medical University, Kashihara, Nara, Japan.

Abstract

Objective: Intraprocedural rupture (IPR) is a rare complication that can occur during endovascular treatment (EVT) of unruptured intracranial aneurysms (UIAs). However, it leads to high morbidity and mortality rates. Others have showed that coil flexibility is a risk factor for IPR. Neuroform Atlas (NA) stents can be deployed with 0.0165-inch microcatheters to enable stent assisted coiling (SAC) with a high likelihood. Undersized flexible coils can be inserted initially during SAC. This study aimed to determine whether SAC using NA and highly flexible coils for UIAs can be conducted without IPR.

Methods: We retrospectively analyzed nine consecutive patients (mean age, 73.2 years; female, n = 6) who underwent SAC for UIAs combined with NA stents and undersized flexible coils between January 2017 and December 2019. Two aneurysms were located at the internal carotid artery (ICA), and one each was located at the ICA-posterior communicating, anterior communicating, middle cerebral, vertebral, vertebra-posterior inferior cerebral and basilar arteries. The mean size of the aneurysms was 4.6 (range, 3.1-8.6) mm. SAC proceeded using the jailing technique. All coils were selected from among the most flexible coils available. We retrospectively assessed technical success rates, aneurysm occlusion at final digital subtraction angiography (DSA), volume embolization ratios (VERs), rates of IPR and symptomatic stroke within 30 days, angiographic findings of aneurysm occlusion at 3 months post-procedure and late adverse events (frequency of aneurysmal rupture, ipsilateral ischemic stroke, and retreated targeted aneurysms).

Results: The technical success rate was 100%. Complete occlusion (CO) was immediate in 8 (89%) patients and a neck remnant persisted in 1 (11%). No IPR or symptomatic stroke developed within 30 days. During a mean follow-up period of 11.8 months, CO persisted in 8 (89%) patients. No late adverse events occurred.

Conclusion: The early clinical and angiographic findings of SAC for UIAs combined with an NA stent and undersized flexible coils were favorable for this series.

Keywords: Neuroform Atlas; coil embolization; unruptured intracranial aneurysm.