Predictive factors of incomplete aneurysm occlusion after endovascular treatment with the Pipeline embolization device

Abstract

OBJECTIVEThe Pipeline embolization device (PED) is a routine choice for the endovascular treatment of select intracranial aneurysms. Its success is based on the high rates of aneurysm occlusion, followed by near-zero recanalization probability once occlusion has occurred. Therefore, identification of patient factors predictive of incomplete occlusion on the last angiographic follow-up is critical to its success.METHODSA multicenter retrospective cohort analysis was conducted on consecutive patients treated with a PED for unruptured aneurysms in 3 academic institutions in the US. Patients with angiographic follow-up were selected to identify the factors associated with incomplete occlusion.RESULTSAmong all 3 participating institutions a total of 523 PED placement procedures were identified. There were 284 procedures for 316 aneurysms, which had radiographic follow-up and were included in this analysis (median age 58 years; female-to-male ratio 4.2:1). Complete occlusion (100% occlusion) was noted in 76.6% of aneurysms, whereas incomplete occlusion (≤ 99% occlusion) at last follow-up was identified in 23.4%. After accounting for factor collinearity and confounding, multivariable analysis identified older age (> 70 years; OR 4.46, 95% CI 2.30–8.65, p < 0.001); higher maximal diameter (≥ 15 mm; OR 3.29, 95% CI 1.43–7.55, p = 0.005); and fusiform morphology (OR 2.89, 95% CI 1.06–7.85, p = 0.038) to be independently associated with higher rates of incomplete occlusion at last follow-up. Thromboembolic complications were noted in 1.4% and hemorrhagic complications were found in 0.7% of procedures.CONCLUSIONSIncomplete aneurysm occlusion following placement of a PED was independently associated with age > 70 years, aneurysm diameter ≥ 15 mm, and fusiform morphology. Such predictive factors can be used to guide individualized treatment selection and counseling in patients undergoing cerebrovascular neurosurgery.

Pipeline Embolization Device for intracranial aneurysms in a large Chinese cohort: factors related to aneurysm occlusion

“… 12 – 14 Also, the PLUS cohort included a large number of off-label cases (i.e. ruptured aneurysms; fusiform, dissecting, and blister aneurysms; posterior circulation and distal Willis aneurysm) than previous cohort studies, 1 , 7 , 15 while the conventional indications for the PED use include wide-necked intracranial aneurysms in the internal carotid artery from the petrous to the superior hypophyseal segments. 16 …”

2D parametric contrast time-density analysis for the prediction of complete aneurysm occlusion at six months’ post-flow diversion stent

“…3,[5][6][7] These models attempt to predict the occlusion rate based on aneurysm geometry, location, size, degree of initial aneurysm occlusion, and presence of contrast stasis after FDS deployment. 6 In a study by Maragkos et al, 12 aneurysms were plotted by size in 5-mm increments to determine incomplete occlusion rates. They found a sharp decrease in occlusion rates in aneurysms !…”

“…15 mm in diameter, which served as an independent negative predictor of occlusion. 12 Other predictive factors have also been studied, including the number of FDS, follow-up duration, and ostium or neck ratio. The entire concept of the flow diversion is to create a flow stagnation within the aneurysm itself.…”

“…3,[5][6][7][8][9] Several studies have investigated factors able to predict aneurysm occlusion rate at follow-up; predictors associated with poor aneurysm occlusion include larger aneurysm size, larger ostium or neck ratios, shorter follow-up time, patient age >70 years, and fusiform morphology. [10][11][12] Smoking, instead, is associated with higher rate of aneurysm thrombosis. 10 The identification of risk factors for incomplete aneurysm occlusion after FDS treatment is still an ongoing investigation, and hemodynamic evaluation is recently gaining attention.…”

Endovascular Treatment of Brain Aneurysms

“…With this change comes a great void in experience and skill in the open surgical management of brain aneurysms. It remains to be seen whether this skill will be needed in the future [97].…”