Balloon-assisted Guglielmi detachable coiling of wide-necked aneurysms: Part I - Experimental evaluation

OBJECTIVE: Balloon-assisted technique is a promising technical adjunct to u se of Guglielmi detachable coils for embolization of wide-necked aneurysms. In this study using experimental aneurysms in swine, the safety and long-t erm efficacy of this technique were evaluated. METHODS: Sixteen wide-necked aneurysms (sidewall model) were surgically cre ated in common carotid arteries of swine. In the acute study of eight aneur ysms, intra-aneurysmal pressure changes were recorded during balloon inflat ion in different positions of the balloon relative to the neck of the aneur ysm. In the chronic study, eight aneurysms were treated with this technique , and follow-up angiography was performed 14 days postembolization. The ani mals were then killed for macroscopic evaluation. RESULTS: In the acute study, the systolic intra-aneurysmal blood pressure i ncreased with balloon inflation at the distal portion of the neck and with balloon inflation/occlusion across the entire neck of the aneurysm. In the chronic study, seven of eight cases were embolized with satisfactory occlus ion, and six showed no coil displacement on the follow-up angiogram. In fiv e cases, macroscopic evaluation of the aneurysm showed that the coils were compacted at the neck of the aneurysm with a concave shape consistent with the shape of the inflated balloon across its neck. CONCLUSION: This preliminary study indicates that balloon-assisted Guglielm i detachable coiling technology may produce a temporary increase of pressur e within the aneurysm while occluding the aneurysmal neck during coil deliv ery. This sudden change of intra-aneurysmal pressure may potentially be the cause of aneurysm rupture in the clinical setting. The balloon must be inf lated and deflated very slowly to minimize these potentially risky hemodyna mic changes. Although angiographic follow-up showed successful obliteration of aneurysms, further long-term angiographic studies ave necessary to esta blish the durability of this technique.