gms | German Medical Science

Objective: Blister-like aneurysms are very rare intracranial aneurysms. They are localized at nonbranching sites of arteries with tendency to progress in size over a short period. Because of the high risk for premature rupture or parent vessel tears surgical treatment of these fragile lesions has been associated with a high morbidity and mortality rate. Endovascular treatment with coil embolization is not a valuable treatment option because of regrowth and rebleeding of the aneurysms that neither stents nor balloons can helpfully prevent. With flow diverter stents we became a new option for a safe treatment of this kind of aneurysms through an exclusively endoluminal approach. We describe five cases of successful endovascular treatment with flow diverter stents.

Method: Five cases of blister-like internal carotid aneurysm with a diffuse subarachnoid hemorrhage (SAH) in the basal cisterns treated with flow diverter stents were retrospectively analyzed. The treatment course, clinical outcome and angiographic signs of aneurysm obliteration over the follow-up time between Mai 2010 and October 2012 were evaluated.

Results: The initial angiograms obtained within the first days after the SAH showed only small fusiform widening on the distal ICA without saccular aneurysm in four patients, only one patient had a typical small broad-neck saccular aneurysm on the medial wall of the distal ICA. Control angiography was performed in the first 2 weeks in the patients without aneurysm detection and blister like aneurysms at the internal carotid were confirmed. All five patients were treated with flow diverter stents. The postoperative clinical course was uneventful in four patients; these patients were discharged without new neurological deficits. In two patients ventriculo-peritoneal shunts were placed due to hydrocephalus; one of them also developed severe cerebral vasospasm. Angiographic follow ups were performed six months after endovascular treatment in four patients, in three patients these have showed a complete obliteration of the aneurysm as well as a sufficient reconstruction of ICA wall. One patient had a residual aneurysm, which was successfully obliterated by endovascular coiling ten months after the initial treatment.

Conclusions: Endovascular techniques are a useful treatment option for these fragile aneurysms. Our findings suggest that parent vessel reconstruction with flow diverter stents also after SAH appears to be a safe and effective option in the management of blister like aneurysms.