Endovascular treatment for complex intracranial aneurysms: lessons learnt in five patients

Complex cerebral aneurysms: intra-luminal reconstruction using Pipeline flow-diverting stent and the obliteration mechanism

OBJECTIVES

Patients with complex cerebral aneurysms can now be treated intravascularly with the help of flow-diverting stents. The primary purpose of this article is to document the clinical and angiographic outcomes in 80 patients who were treated with the Pipeline flow-diverting stent (PFS; Medtronic, Dublin, Ireland) and the obliteration mechanism was discussed.

PATIENTS AND METHODS

Between October 2015 and October 2019, 80 patients with 90 complex (undefined neck, large/giant, blood blister-like, and recurrent side-wall) cerebral aneurysms treated with the PFS were retrospectively reviewed. Forty-five patients were women and 35 were men, with a mean age of 52 years. Large or giant aneurysms were defined as 10 mm or larger and small aneurysms were defined as less than 10 mm at the largest diameter measured on angiogram.

RESULTS

Forty-one aneurysms (45.6%) were large or giant, 41 (45.6%) were small, four (4.4%) were recurrent side-wall aneurysms and four (4.4%) were blood blister-like aneurysms. In total, 87 PFSs were placed in 80 patients with 90 aneurysms. In six patients, coexisting proximal stenosis of parent artery was also covered with PFS without balloon angioplasty. Adjunct coils were placed in 31 aneurysms (34%). One patient died of intracerebral hematoma after thrombolysis. There was one intrastent occlusion at six-month follow-up without any symptoms. The morbidity and the mortality rate is 0% and 1.3% (95% confidence interval (CI), 0%-3.7%). Control angiography was available in 74 (92.5%) patients with 83 aneurysms, and the aneurysm occlusion rate was 98.8% (95% CI, 96.5%-100%) in 6 to 12 months.

CONCLUSION

For wide-necked saccular, large/giant, blood blister-like aneurysms and recurrent side-wall aneurysms, PFS is a valid and safe treatment option.

Rupture of Intradural Giant Aneurysms: The Mode of Treatment, Anatomical, and Mechanical Factors

OBJECTIVE

Aneurysm rupture is often a fatal complication of giant intradural aneurysm (GIA) treatments. The purpose of this study was to review aneurysm rupture in GIA treatment.

MATERIALS AND METHODS

We performed a systematic review on aneurysm rupture related to GIA treatment. For each reported case, we collected the following information: aneurysm location, size and rupture status, the mode of treatment, timing of the hemorrhage, anatomical, and hemodynamic factors.

RESULTS

We identified 56 aneurysm ruptures related to treatment in 38 published studies. Of the nine intraoperative ruptures, eight occurred during endovascular procedures and one in surgical treatment. Of the 47 delayed ruptures, 72.3% occurred within 2 weeks. The prognosis of intraoperative and delayed ruptures was poor, with 83.9% experiencing death. Of these aneurysms, 75% were initially unruptured. Of the delayed ruptured aneurysms, 21.3% had prior surgical treatment, 74.4% had prior endovascular treatment, and 4.3% had prior combined surgical and endovascular treatments. Vertebrobasilar artery (VBA) location was significantly associated with aneurysm rupture after treatment, occurring at 57.2%. Flow diverter (FD) treatment seemed to elevate the delayed rupture proportion of giant paraclinoid internal carotid artery (ICA) aneurysms from 22.0% to 42.9%. FD treatment did not lower the rupture risk of giant VBA aneurysms and the corresponding death rate.

CONCLUSION

Intraoperative and delayed aneurysm ruptures were the most challenging in endovascular treatment of GIAs. Giant VBA aneurysm had the highest rupture risk after treatment. FD seemed to elevate the delayed rupture proportion of giant paraclinoid aneurysms.

Endovascular treatment of paraclinoid aneurysms

The anatomical complexity of the paraclinoid region has made surgical treatment of intracranial ophthalmic segment aneurysms (OSAs) difficult. This study evaluated the safety and efficacy of endovascular treatment of paraclinoid aneurysms. We conducted a retrospective study of 28 patients with 30 aneurysms of the paraclinoid in whom treatment with endovascular techniques was attempted. Patient age, sex, presence of subarachnoid hemorrhage, aneurysm type, size of aneurismal sac and treatment modality were reviewed. Clinical evaluation and control angiography were performed between one and 43 months. Overall, complete occlusion was obtained in 26 aneurysms (86.6%), nearly complete (>90%) occlusion in two aneurysms (6.7%) and incomplete occlusion was observed in two aneurysms (6.7%). All endovascular techniques were successful. Procedure-related complications were observed in two patients (7.1%). Patients underwent follow-up for a mean of 14.8 months (range 1-43 months). Repeated coil treatment was performed in one patient. One patient died of massive brain infarction six days postoperatively and thus no follow-up data were available for this case. In 27 patients with follow-up studies, aneurysm closure was complete in 22 (81.5%) and incomplete in five (18.5%). Endovascular treatment is a safe and efficient alternative approach for paraclinoid aneurysms.

Using Onyx in endovascular embolization of internal carotid artery large or giant aneurysms

BACKGROUND AND PURPOSE

Internal carotid artery (ICA) large or giant saccular aneurysms is challenging for endovascular coil embolization and surgical clipping with a high recanalization and rebleeding rate. We report our results using Onyx in the endovascular treatment of ICA large or giant saccular aneurysms.

METHODS

During 2008-2010, 5 patients with 5 large or giant saccular aneurysms in ICA were treated with a liquid embolic agent (Onyx; Micro Therapeutics, Irvine, CA). One aneurysm was small (<10mm), 2 were large (≥10mm, <25mm) and 2 were giant saccular aneurysms (≥25mm). Of 3 female and 2 male patients, 3 were incidental and 2 had bleeding. Selective embolization was performed with Onyx alone or a combination with coils. Clinical and anatomic outcomes were assessed with the Modified Glasgow Outcome Scale and follow-up angiography was performed at 4-21 months (mean 12.2 months).

RESULTS

Complete aneurysm occlusion was obtained in all of the aneurysms on immediate control angiogram. There was not any procedure-related complication. No recanalization was observed at the follow- up periods. There were 2 ICA occlusions in giant ICA aneurysms. The 5 patients were all clinically asymptomatic at follow-up.

CONCLUSION

Endovascular embolization with Onyx is a useful treatment for ICA large or giant aneurysms, which is unsuitable for coiling or surgical treatment.