A single-center retrospective study of the COCO technique in the treatment of chronic internal carotid artery occlusion.

Objective: To introduce a novel endovascular recanalization method and to investigate its success rate, periprocedural complications, and early outcomes in patients with chronic internal carotid artery occlusion (CICAO). As this novel technique was designed to treat ICA with a full axial system, we named it the COCO technique.

Methods: Data from consecutive patients with symptomatic CICAO who underwent endovascular recanalization in our institution were retrospectively reviewed. The COCO technique allows extracranial angioplasty and stenting with occasional intracranial angioplasty and stenting as needed to be performed in a coaxial fashion. Patients' demographic and clinical information, morphologic characteristics, procedural results, complications, and follow-up outcomes were recorded.

Results: Forty-nine patients were enrolled in this study. The technical success rate was 89.8% (44/49). Four patients experienced intraoperative complications, two patients had a slight subarachnoid hemorrhage, and two patients had asymptomatic dissection. Distal embolization or carotid-cavernous arteriovenous fistula was not detected. In addition, three patients developed hemorrhagic complications and three developed postoperative ischemic complications. All these patients improved after conservative treatment and subsequent rehabilitation. During the median 6 (3-6) months of follow-up, one patient died of severe pneumonia and two patients experienced recurrent ischemic events. In patients with successful recanalization, modified Rankin Scale scores were lower at the 3-month follow-up than at baseline (1 (0-2) vs 2 (1-2), P=0.04). Restenosis was observed in six (15.8%) patients.

Conclusions: Our study showed that the COCO technique is effective and safe for endovascular recanalization in patients with CICAO and has low periprocedural complications and favorable functional outcomes.