Treatment of Small and Tiny Aneurysms Before and After Flow Diversion Era: A Single Center Experience of 409 Aneurysms.

OBJECTIVE: To explore whether we should use the Pipeline embolization device (PED) as the primary treatment modality for small and tiny aneurysms at anterior circulation.

METHODS: This retrospective study included 409 cases of small and tiny aneurysms, including aneurysms treated by the PED (n = 77), coiling (n = 51), and stent-assisted coiling (SAC) (n = 281). We also made a comparison regarding the safety and efficacy among these treatment modalities.

RESULTS: A total of 55 patients with 77 small aneurysms were treated with PEDs. Technical success was achieved in 98.4% of procedures. The complete occlusion rate was 75.9% (44/58). Both the morbidity and mortality rates were 1.8%. Comparing the 3 treatment modalities, the technical event rate tended to be the highest in the PED group (4.8% vs. 2.0% and 1.1%; PED vs. Coil vs. SAC; P = 0.100), and the use of a PED neither significantly shortened the procedure duration (127.2 ± 62.8 vs. 115 ± 37.1 and 112.8 ± 40.6 minutes, P = 0.322) nor lowered the complication rate (11.1% vs. 9.8% and 6.1%; P = 0.281). SAC had the highest occlusion rate (75.9% vs. 75.8% and 94.0%; P < 0.001) and lowest morbidity rate (0.8% vs. 4.2% and 1.8%; SAC vs. Coil vs. PED; P = 0.099). Ipsilateral multiple aneurysms were more frequently seen in the PED group (33.8% vs. 3.9% and 3.2%; P < 0.001). Procedure duration tended to be lower in the PED group versus the SAC group (122.7 ± 57.4 vs. 157.5 ± 22.2 minutes; P = 0.060). For these aneurysms, the PED group had the highest occlusion rate (80.0% vs. 50.0% and 66.7%; P = 0.516).

CONCLUSIONS: The PED is an alternative treatment for small and tiny aneurysms. However, SAC remains the safest and most efficient treatment modality. The PED should be reserved for ipsilateral multiple aneurysms.