To explore the therapeutic effect and strategy of endovascular embolization in the treatment of moyamoya disease complicated with intracranial aneurysm.

25 cases (25 aneurysms) of moyamoya disease with intracranial aneurysms were collected at the Fifth Medical Center of PLA General Hospital from March 2013 to September 2019. For trunk aneurysms, simple coil embolization was directly performed for narrow-neck aneurysms. Double microcatheter, balloon-assisted and stent-assisted embolization was performed for wide neck aneurysms. For peripheral aneurysms, coil embolization was used for true aneurysms and liquid embolic agent (Onyx-18) was used for pseudoaneurysms. The effects of operations were observed and followed up after operation. Fisher accurate probability method was used to compare the incidence of complications between true aneurysms and pseudoaneurysms.

Stent-assisted coil embolization was used in 7 cases, simple coil embolization in 9 cases with one case complicated with ruptured hemorrhage and mild headache after operation. The 9 cases of pseudoaneurysms were embolized by liquid embolic agent (Onyx-18), and 5 of them had different degree of neurological dysfunction after operation. The incidence of postoperative complications of pseudoaneurysm was significantly higher than that of true aneurysm (55.6%[5/9] vs 6.3%[1/16], P=0.012). After 3~26 months (mean 12.6 months), the aneurysms were all cured without recurrence and residual. No intracranial hemorrhage occurred in 7 patients treated with stent-assisted coils embolization during the period of taking clopidogrel plus aspirin from one week before operation to 3 months after operation, and no stent restenosis was observed during whole cerebral angiography.

Endovascular embolization is an important method to treat moyamoya disease with intracranial aneurysm. There was no significant increase in the risk of intracranial hemorrhage in moyamoya disease and intracranial aneurysm when shortly taking clopidogrel plus aspirin. The incidence of complications after endovascular embolization of pseudoaneurysm was higher than that of true aneurysm.