Introduction: Middle cerebral artery (MCA) aneurysms are generally considered suitable for microsurgical clip ligation but recent introduction of various intraluminal stents might shift the treatment paradigm towards endovascular treatment. We report our single-center experience with both modalities for treatment of unruptured MCA bifurcation aneurysms.
Methods: Patients treated for unruptured MCA bifurcation aneurysm from 2011 to 2016 were retrospectively included. Fusiform, complex and giant aneurysms >25mm were excluded. Patients were stratified into a microsurgical- and an endovascular group. The latter was subdivided into a stent-only group, stent assisted coiling group, coil-only group and flow diverting stent group. Aneurysm characteristics, 15-month occlusion rate and clinical outcome were recorded. Raymond Class I occlusion and mRS=1 were defined as successful outcome.
Results: Eighty-one patients with eighty-five aneurysms were included. 29 aneurysms were included in the microsurgical group, 56 aneurysms were included in the endovascular group. 24 aneurysms were treated with stent assisted coiling, 24 aneurysms with flow diverting stent, 5 aneurysms with a non-flowdiverting stent, 3 aneurysms with coils only. No difference in aneurysm characteristics was found but neck/dome ratio in the coil-only group was smaller than the other endovascular subgroups (p=0.08).
Raymond Class I was achieved in 100% and 69.4% of the aneurysms in the microsurgical and endovascular group respectively. In the latter group occlusion rate was 84.2% for stent-assisted coiling, 65.2% for flowdiverters, 0% for non-flowdiverters and 100% for coil-only groups. These differences were significantly inferior to microsurgical clip ligation except for the stent-assisted coil group (p=0.064) and coil-only group (p=1.00).
Favorable outcome was achieved in 93% and 98.2% of the patients in the microsurgical and endovascular group respectively (p=0.58). No patient had a mRS>2 after treatment.
Conclusions: Microsurgical clip ligation provides superior obliteration rate compared to endovascular treatment with comparable clinical outcome for the treatment of “uncomplicated” MCA bifurcation aneurysms.
Patient Care: Proposes best treatment modality
Learning Objectives: Microsurgical clipping of unruptured middle cerebral artery bifurcation aneurysms is still the treatment of choice