Complications in the treatment of intracranial aneurysms with silk stents: an analysis of 30 consecutive patients

Abstract

Flow-diverting stents (Silk and PED) have radically changed the approach to intracranial aneurysm treatment from the use of endosaccular materials to use of an extraaneurysmal endoluminal device. However, much debate surrounds the most appropriate indications for the use of FD stents and the problems raised by several possible complications.We analysed our technical difficulties and the early (less than ten days after treatment) and late complications encountered in 30 aneurysms treated comprising 13 giant lesions, 12 large, five with maximum diameters <10 mm and one blister-like aneurysm. In our experience the primary indications for the use of FD stents can be the symptomatic intracavernous giant aneurysms. Although the extracavernous carotid siphon aneurysms have major risk of bleeding, FD stents are indicated clearly explaining the risks to the patient in case of severe mass effect. There is a very complex assessment for aneurysms of the vertebrobasilar circulation.

Figure 1

Two different images of small multiple aneurysms of the ophthalmic tract of the internal carotid siphon in two different patients. The siphon tortuosity and the anatomy of aneurysms suggests much difficulty in the catheterization and release of coils in the aneurysm sacs. In particular in one case (A) we found that the ophthalmic artery borns by aneurysm sac.

Figure 2

A) The position where the guide tip was accidentally blocked during stent release (ring). When we performed a final angiographic control (B) we observed a leakage of contrast into the interpeduncular cistern (*). Two days later, CT control (C) disclosed a right thalamic ischaemic lesion (black arrow) and subtotal reabsorption of leakage of contrast. Two months later, CT angiography follow-up control showed the aneurysm occlusion, regular view of the PICA (white arrow), good position of the Silk stent and presence of the coils (arrowhead) that we used to block the haemorrhage due to the artery of Percheron perforation.

Figure 3

Two year follow-up post-treatment angiographic control showed a slow and poor blood flow distal to the stent (A,C). However the injection of contrast in the contralateral internal carotid artery demonstrated a good haemodynamic compensation of the flow through the circle of Willis and hypertrophic collateral pial vessels (B,D).

Figure 4

3D reconstruction angiogram of the internal left carotid artery injection showed multiple aneurysms (A). The largest paraophthalmic aneurysm (arrow) was treated with Silk stent apposition. Intraoperative images in lateral projection demonstrated a good position release of the stent (B). Subsequent serial angiographic control showed stent migration in left M1 segment with clip and coils implanted in previous treatments.

Figure 5

A-C) The MR image shows a giant basilar aneurysm and its massive compression on the bulb (*). Angiographic examination confirms the giant aneurysm that was treated with one Silk stent (white lines). D-F) CT controls post endovascular treatment showed acute hydrocephalus that was treated by external CSF drainage (ring), but it resulted in massive intra-axial and intraventricular haemorrhage.

Figure 5

A-C) The MR image shows a giant basilar aneurysm and its massive compression on the bulb (*). Angiographic examination confirms the giant aneurysm that was treated with one Silk stent (white lines). D-F) CT controls post endovascular treatment showed acute hydrocephalus that was treated by external CSF drainage (ring), but it resulted in massive intra-axial and intraventricular haemorrhage.

Figure 6

Post-treatment angiographic control showed a good position release of the Silk stent (A). CT control performed because the patient had a severe clinical worsening revealed a massive cerebral hemorrage (B). The patient underwent emergency neurosurgical evacuation of the haematoma and the surgeon deemed it essential to complete the internal carotid artery occlusion but this led to a massive cerebral hemispheric ischaemic lesion (C).

Figure 7

LL cerebral angiography releaved a giant paraophthalmic aneurysm (A). Three months after endovascular treatment the patient presented left hemiparesis due to some ischaemia and a M1 stenosis displayed respectively by MR scan (B-C) and MR angiography (D).

Figure 8

Partially thrombosed giant aneurysm of basilar artery compressing the bulb (A). Two months after treatment the follow-up MRA showed a increase and change in the thrombosis portion (red rings) and a congruent bulb ischaemic lesion (white arrows) (B,C).