gms | German Medical Science

Objective: The rate of intracranial aneurysm remnants/recurrences after microsurgical clipping varies between 2% and 42%. The optimal management for these patients, however, remains a matter of debate. Especially repeat surgery bears a high risk of periprocedural complications due to scarring and anatomic distortion from prior procedures. This study aims to evaluate the risk-/benefit-profile of flow diverter stents as an endovascular treatment options for these patients.

Methods: The patient database of our neurovascular hybrid center was queried to identify patients with clipped aneurysms who subsequently underwent endovascular treatment with flow diverter stents (intraluminal, self-expanding). The outcome analysis consisted of an assessment of clinical parameters (modified Rankin Scale; mRS) and the postinterventional angiographic occlusion status (Sindou classification).

Results: Six patients (median age: 51 years) underwent endovascular treatment via flow diversion of recurrent clipped aneurysms. Treatment was necessary in two patients due to progressive neurological dysfunction and in four patients due to angiographic proof of an increasing aneurysm size. Locations of the aneurysm were the middle cerebral artery (n=2), the anterior communicating artery (n=2), the posterior communicating artery (n=1) and the bifurcation of the internal carotid artery (n=1). Median aneurysm size was found to be 0.45 cm (range: 0.1-1.9 cm). All patients had a prior history of subarachnoid hemorrhage; time from primary clipping to recurrence was 10.6 years (range 6.9 months – 30.9 years). Complete radiological aneurysm occlusion was feasible in 5 cases, a remnant portion of the aneurysmatic sac (Sindou grade IV) on early angiography was seen in one case only. Two patients who had suffered from preinterventional neurological deficits (visual deficits and sensorimotor dysfunction) showed a complete remission of symptoms on last follow-up; the last recorded mRS was 0 in 3 cases and 1 in 3 patients. No periprocedural morbidity or mortality was recorded and none of the patients required retreatment in the median follow-up of 8 months.

Conclusion: This preliminary case series suggests that endovascular treatment via flow diverter stenting of aneurysms remnants after prior microsurgical clipping is a feasible treatment concept with a low-risk profile which might prevent the treatment burden of repeat surgery.