Flow diverters and a tale of two aneurysms.

Flow-diverting devices offer an exciting alternative for the management of large and giant intracranial aneurysms. However, the risk and mechanism of delayed aneurysmal rupture and hemorrhage following placement of these devices are not clearly understood. Two patients with similar symptomatic giant paraclinoid internal carotid artery aneurysms are described. Both patients were treated with SILK flow-diverting devices. In both patients the SILK device was placed without technical complication. The first patient continued to do well 1 year postoperatively with complete aneurysm occlusion. The second patient had a delayed subarachnoid hemorrhage despite markedly decreased filling of the aneurysm immediately following the procedure. Flow-diverting devices are an exciting technology which provide an alternative treatment modality in the management of giant intracranial aneurysms. However, caution must be exercised as the risks of delayed complications have yet to be fully elucidated. Similar aneurysms may have drastically different outcomes due to the unpredictability of this technology.

Evolution of treatment options for vein of Galen malformations.

OBJECT: Vein of Galen aneurysmal malformations (VGAMs) continue to account for high morbidity and mortality rates in the pediatric population. Whereas in the past, mortality rates were nearly 100%, recent developments in endovascular embolization and improvements in neonatal care have improved prognoses. It is now possible that some patients can achieve normal neurological development following embolization of the VGAM. Access to the lesion can be gained via transarterial or transvenous routes. In this paper the authors review the pathophysiological characteristics of VGAM and discuss the evolution of treatment options. METHODS: A PubMed literature search was performed for vein of Galen malformation treatment options, beginning in the 1970s. A total of 22 papers were reviewed in full, and outcome data for 615 patients from 1983 to 2010 were compiled. Articles were reviewed if they focused primarily on the treatment of VGAM and reported outcomes for at least 5 treated patients. RESULTS: Of the 265 patient outcomes reported between 1983 and 2000, 200 received endovascular therapy. Of these patients 72% had a favorable outcome, and a 15% mortality rate was found. Microsurgery was found to have an 84.6% mortality rate. Furthermore, 76.7% of untreated patients died. More recently, endovascular embolization has become the mainstay of VGAM treatment. Of the 350 patients assessed between 2001 and 2010, 337 were treated endovascularly, mostly via the transarterial approach. Of these patients, 84.3% were found to have good or fair outcomes, and a 15.7% mortality rate was found. Neonates had the worst clinical outcomes following endovascular treatment, with a 35.6% mortality rate, whereas infants and children had significantly better outcomes, with mortality rates of 6.5% and 3.2%, respectively. CONCLUSIONS: Endovascular embolization has considerably improved outcomes in patients with VGAM. In the past, the prognosis for patients with VGAM was dismal, and successful procedures were considered to be those that partially or completely obliterated the lesion, but did not necessarily improve the patient's symptoms. More recently, with the continued development and improvement of endovascular techniques, many patients are found to be neurologically normal on follow-up, and mortality rates have dropped substantially when compared with microsurgical treatment.