Treatment of a ruptured dissecting vertebral artery aneurysm with double stent placement: case report

Abstract

A ruptured dissecting right vertebral artery aneurysm was treated by means of double stent placement with two overlapping stents. Control angiography performed 3 d after stent placement revealed beginning aneurysmal thrombosis. Substantial reduction in aneurysmal size was observed after 4 wk, whereas total occlusion was observed after 3 mo. The reduced stent porosity caused by the overlapping stents, which result in significant hemodynamic changes inside the aneurysmal sac, may accelerate intraaneurysmal thrombosis and may be helpful in achieving a more rapid complete occlusion compared with that achieved by single stent placement.

fig 1.

Initial images. A, Transverse CT scan obtained on the day of admission. Blood is present within the prepontine subarachnoid space and fourth ventricle. B, Anteroposterior arteriogram obtained with a right vertebral artery injection. Fusiform dilatation of the distal vertebral artery, distal to the posterior inferior cerebellar artery origin, indicates intracranial dissection (arrow).

fig 2.

Follow-up anteroposterior arteriograms obtained with a right vertebral artery injection 5 wk after bleeding. A, Image shows aneurysmal growth (arrow) of approximately 8 mm. B, Image shows a further slight increase (arrow) in the size of the dome, 5 d later.

fig 3.

Arteriograms obtained after stent placement. A and B, Anteroposterior projection arteriograms obtained immediately after stent placement. After deployment of two overlapping stents (S670, 3/12 and 3/18 mm) distal to the posterior inferior cerebellar artery origin, the aneurysmal neck is fully covered by the portion with reduced porosity. The vertebral artery is patent, and the aneurysm still shows filling; however, a minimal delay in the washout of the intraaneurysmal filling is observed (arrow). C, Right anteroposterior-oblique arteriogram obtained 3 d after stent placement. The overlapping stents are patent, but the aneurysmal dome shows some small filling defects adjacent to the aneurysmal wall (arrow) consistent with the beginning of intraaneurysmal thrombosis. A small amount of contrast medium is seen in the space between the stents and the proximal vessel wall where the stents are not completely adjacent to the vessel wall (arrowheads). D, Lateral orthogonal projection of the course of the artery, obtained 3 d after stent placement, more clearly shows the circumferential extent of the pseudoaneurysm (arrow) during the post–stent-placement stage E, Right anteroposterior-oblique arteriogram obtained 4 wk later. The two stents are patent, whereas the aneurysm shows subtotal occlusion. The filling of the extra space is now diminished in its extension (black arrowheads) and corresponds to the decreased size of the pseudoaneurysm in F. This probably does not represent the original arterial wall but rather the dissecting membrane that is the initial part of the developed pseudoaneurysm. Miniature: nonsubstracted image of the two stents shows the overlapping portion between the white arrowheads. F, Lateral orthogonal projection of the course of the stented artery, obtained 4 wk after stent placement, more clearly shows the circumferential extent of the pseudoaneurysm (arrow) during the regression stage. G, Right anteroposterior-oblique arteriogram obtained 3 mo after stent placement shows complete occlusion of the pseudoaneurysm, with minimal extravasation in the area of the previously dissected arterial wall (arrowhead). A patent right vertebral artery with no notable intimal hyperplasia is depicted. H, Lateral orthogonal projection of the course of the stented artery, obtained 3 mo after stent placement, more clearly shows the total occlusion of the pseudoaneurysm (arrow).

fig 4.

Illustration of the reduction of the intra-aneurysmal flow caused by decreased porosity due to double stent placement