Safety and mid-term outcome of Pipeline embolization device in the treatment of complex intracranial aneurysms

Abstract

Objective To evaluate the mid-term safety and efficacy of Pipeline embolization device (PED) in the treatment of complex intracranial aneurysms. Methods A retrospective analysis was conducted on the clinical data of 53 patients with 70 complex intracranial aneurysms who underwent endovascular interventional treatment at the Cerebrovascular Division of Interventional Department, People＇s Hospital of Zhengzhou University from January 2015 to October 2016. All patients were implanted with PED through the femoral artery under general anesthesia. Digital subtraction angiography (DSA) was performed at the end of the operation to examine the position and possible malposition of PED, and the CT scans were performed to assess intracranial hemorrhage. The CT or MRI scans were performed on day 5-7 post operation if necessary, and the modified Rankin Scores (mRS) were used to evaluate the prognosis of the patients. Clinical follow-up was performed at 3, 6, 12 and 24 months post operation and the prognosis was evaluated based on the mRS scores. The imaging follow-up was performed at 6, 12 months post operation, and the degree of aneurysm occlusion was graded by OKM (O＇ Kelly-Marotta) grading scale. Results All 53 patients with 70 aneurysms were successfully implanted with 58 PEDs. Among them, 45 aneurysms were treated with PED alone and 25 aneurysms were treated with PED-assisted coil embolization. At the end of the operation, the DSA examination showed that PEDs were all accurately covered with the aneurysm necks and complete stent apposition was observed. No intracranial hemorrhage was revealed by CT scan. Perioperative complications occurred in 5 patients (9.4%, 5/53). At 5-7 days post operation, the CT or MRI scan showed subarachnoid hemorrhage in 1 patient, cerebral hemispherical swelling at PED-implanted side in 1 and acute cerebral infarction in 1. The mRS scores were assessed and they were 0 in 25 patients, 1 in 23, 2 in 1, 4 in 3 and 6 in 1. A total of 47 patients obtained clinical follow-up 10-30 months post operation with a median of 16 (14, 20) months. The mRS scores were 0 in 38 patients, 1 in 6, 2 in 1, 3 in 1 and 4 in 1. There were 43 patients (58 aneurysms) who obtained imaging follow-up 3-19 months post operation with a median of 6 (4.5, 10.0) months. The OKM scale of 58 aneurysms in 43 patients were assessed which indicated grade D in 34 patients, C in 9 and B in 15. Complete and subtotal occlusion was conducted for 43 out of 58 aneurysms (74.1%, 43/58) with no recurrence. Conclusions The treatment of complex intracranial aneurysms with PED seems safe and effective in mid-term follow-up and serious complications remain to be noted. Long-term safety and efficacy needs to be further studied. Key words: Intracranial aneurysm; Cerebral revascularization; Treatment outcome; Follow-up studies; Pipeline embolization divice