Background and Aims: For long-segment chronic symptomatic internal carotid artery occlusion (ICAO), either carotid endarterectomy (CEA) or endovascular surgery has its respective limitations. However, the reports on the efficacy of their combined surgery are still not enough. Therefore, this study was conducted to investigate the safety and effectiveness of CEA combined with endovascular technique in the treatment of chronic symptomatic ICAO. 
Methods: The clinical data of 37 patients with long-segment chronic ICAO (involving at least the petrous or more distal segments) undergoing combined surgery from March 2017 to June 2019 were retrospectively analyzed. The proximal occlusion lesion located at the cervical segment (C1 segment) in all patients, the distal occlusion lesion extended to the cavernous segment (C4 segment) or more proximal segments in 20 patients (proximal group), and the distal occlusion lesion extended to clinoid segment or more distal segments in 17 patients (distal group). The changes in clinical symptoms, the scores of the modified Rankin scale (mRS) before and after operation as well the CTA reviewed 3 to 6 months after operation of the patients were analyzed.
Results: All 37 patients with received combined surgical treatment, of whom, the occluded segment in 30 cases were successfully recanalized, and the surgical success rate was 81.1%. In proximal group, the overall recanalization rate was 95.0% (19/20), in which, the recanalization rate for either C2 or C3 segment was 100%, and for C4 segment was 66.7% (6/9); in distal group, the overall recanalization rate was 64.7% (11/17), in which, the recanalization rate for C5 segment was 66.7% (6/9), C6 segment was 57.1% (4/7) and C7 segment was 100% (1/1). The overall recanalization rate in proximal group was significantly higher than that in distal group (P=0.033). The clinical symptoms were improved to different extents in the recanalized patients, the postoperative CTA demonstrated a patent right internal carotid artery, and the PWI images at 1 week after operation showed that the intracranial perfusion hemodynamic indicators were significantly improved compared with their preoperative conditions. Follow-up was conducted for 6 to 17 months in the 30 recanalized patients, the patency rate of the target vessel was 90.0% (27/30), which was 94.7% (18/19) in proximal group and 81.8% (9/11) in distal group, and the difference was no significant between the two groups (P=0.543). The mRS score of the patients at 6 months after operation was significantly better than that before operation (t=6.238, P<0.01).
Conclusion: CEA combined with endovascular technique is a safe and feasible method for the treatment of chronic symptomatic ICAO, and the recanalization rate is higher in patients with distal ICA occlusion at the cavernous more proximal segments.