Angiographic follow-up of cerebral aneurysms treated with Guglielmi detachable coils: an analysis of 162 cases with 173 aneurysms

Abstract

Background and purpose: The endovascular approach, with the use of Guglielmi detachable coils (GDC), has been increasingly used to treat ruptured and unruptured cerebral aneurysms in recent years. Our objective was to assess the mid- to long-term radiologic outcome of cerebral aneurysms treated with GDC embolization.

Methods: One hundred and sixty-two patients with a total of 173 aneurysms embolized with GDCs underwent angiographic follow-up 1 to 54 months after the procedure and were reviewed retrospectively. Each angiogram was reviewed by 2 neuroradiologists and 1 neurosurgeon, each of whom made a comparison between the initial and follow-up angiograms. Morphologic outcomes were scored as follows: unchanged, progressive thrombosis, and reopening or regrowth.

Results: Of the 173 aneurysms with GDC embolization, 142 had total or nearly total occlusion, 23 subtotal occlusion, and 8 partial occlusion on the initial angiograms. The incidence of reopening was 17.1% (13/76) in less than 3 months and 6.2% (6/97) between 3 and 6 months after the procedure. Four aneurysms (2.3%) were found to be recurrent in the second follow-up angiography within 1 year after the procedure. The 1-year cumulative recurrent rate was 13.3%. Among 56 aneurysms with a third follow-up angiography in the period of 12 to 54 months after the procedure, 4 (7.1%) displayed a slight enlargement; the long-term cumulative recurrent rate was 20.4%.

Conclusion: The direct and primary causes for aneurysmal recurrence are incomplete and loose packing. The first angiographic follow-up is recommended to be performed at 3 months or earlier for incompletely occluded aneurysms and at 6 months for totally or nearly totally occluded aneurysms. In case of total or nearly total occlusion that remains stable at follow-up, the interval for monitoring should be prolonged appropriately. Retreatment with balloon- or stent-assisted coil embolization is recommended for reopened aneurysms.

Fig 1.

A 45-year-old woman presented with subarachnoid hemorrhage 6 days before this analysis. A, Digital subtraction angiography (DSA) showed an aneurysm of anterior communicating artery (←) with spasm of the A1 segment (arrowhead). B, Postembolization with Guglielmi detachable coils (GDCs), the aneurysm displayed subtotal occlusion (←). C, Follow-up DSA 3 months later showed relief of the spasm of A1 segment and reopening of the embolized aneurysm (←). D, After re-embolization with GDCs, the aneurysm was totally occluded (←).

Fig 2.

A 49-year-old woman presented with subarachnoid hemorrhage. A, Angiography of the left internal carotid artery (ICA) showed a large aneurysm on the C2 segment of the left ICA. B, After Guglielmi detachable coil (GDC) embolization with stent-assisted technique, the aneurysm was nearly totally occluded. C, Angiography of right ICA demonstrated a small aneurysm (arrow) on the right posterior communication artery. D, The small aneurysm was totally packed with GDCs (arrow) 3 months after the large aneurysm had been embolized. E and F, At the 6-month follow-up of the large aneurysm (E) and 3-month follow-up of the small aneurysm (F), the large one was still totally occluded, whereas the neck of the small one had reopened slightly (arrow). G and H, At 14 months, the large aneurysm (G) remained totally occluded to the same degree; at 11 months, the neck of the small aneurysm (H) remained reopened (arrow) as in previous angiography. The small aneurysm continues to be closely monitored.