Parent Artery Occlusion for Unruptured Cerebral Aneurysms: Results of the Japanese Registry of Neuroendovascular Therapy 3

Abstract

Although the current standard treatment for unruptured aneurysms comprises surgical clipping or endovascular coiling, these techniques are not suitable for some cases, such as large, giant, and fusiform aneurysms. Endovascular parent artery occlusion (PAO), which includes internal trapping and proximal occlusion, is a well-established alternative treatment for such cases. Here, we retrospectively reviewed PAO cases from the Japanese Registry of Neuroendovascular Therapy 3, a nation-wide survey of all neuroendovascular therapy cases between 2010 and 2014. This dataset included 274 procedures with a mean patient age of 57.1 years and 55.4% female patients. For the treatment strategy, internal trapping was selected in 213 aneurysm cases (77.7%) and proximal occlusion in 61 aneurysm cases (22.2%). Most of the procedures were successfully completed (272/274: 99.2%). Immediately after treatment, angiographical complete occlusion was achieved in 248 cases (90.5%). Although the feasibility of this technique was excellent, there were 60 periprocedural complications (21.8%), including 48 ischemic complications (17.5%), seven hemorrhagic complications (2.5%). Overall, morbidity and mortality at 30 days postoperative were 5.8% and 0.7%, respectively. Among the pretreatment variables, a patient age of 70 and older was associated with ischemic complications [odds ratio (OR); 2.34, 95% confidence interval (CI); 1.02–5.25; P = 0.04] and a small aneurysm size (<5 mm) was associated with hemorrhagic complications (OR; 9.85, 95% CI; 1.07–221.0; P = 0.04) by multivariate analysis. In conclusion, PAO for unruptured cerebral aneurysms is feasible, but is associated with a complication rate of approximately 20%. Various alternative treatment options should be carefully considered with deconstructive strategies.

Treatment outcomes of large and giant intracranial aneurysms according to various treatment modalities

“…Similar to our study, Nishi et al reported that high complete occlusion rate (90.5%, n = 248) with low morbidity (5.8%) and mortality (0.7%) rate was achieved in their study [20]. PAO can be a definitive and useful modality because (1) it is a simple technique and (2) it shows a high complete occlusion rate and low recurrence rate compared with other modalities [20,30]. However, patients treated with PAO were often exposed to inherent ischemic complications because of its destructive nature [20].…”

“…PAO showed the highest complete occlusion rate (90.0%) and the lowest complication rate (12.5%) in this study. Similar to our study, Nishi et al reported that high complete occlusion rate (90.5%, n = 248) with low morbidity (5.8%) and mortality (0.7%) rate was achieved in their study [20]. PAO can be a definitive and useful modality because (1) it is a simple technique and (2) it shows a high complete occlusion rate and low recurrence rate compared with other modalities [20,30].…”

“…PAO can be a definitive and useful modality because (1) it is a simple technique and (2) it shows a high complete occlusion rate and low recurrence rate compared with other modalities [20,30]. However, patients treated with PAO were often exposed to inherent ischemic complications because of its destructive nature [20]. Thus, a tolerance test should be performed prior to performing PAO [1,17,31].…”

“…Thus, a tolerance test should be performed prior to performing PAO [1,17,31]. Additional risks associated with the revascularization technique (especially high flow bypass) can occur when the patient is intolerable to the test [20,28]. In this study, six patents underwent bypass surgery before PAO.…”

“…PAO is a simple technique and shows a high occlusion rate. However, this technique can be applied to limited cases because of its destructive nature, which potentially leads to severe ischemic complications [20,29,31]. Recently, FDs have become a mainstream treatment of complex aneurysms.…”