Can we have Dr. Namir Adib come on up and give his talk on the risk of branch occlusion and ischemic complications with pipeline embolization device in the treatment of puss or circulation aneurysms? Thank you. All right, thank you so much for having me. My name is Namir Adib. I'm a neurosurgeon resident at Louisiana State University and a former research fellow at Beth Israel Deaconess Medical Center. My talk today is about the risk of branch occlusion and ischemic complications after pipeline placement in treatment of puss or circulation aneurysms. This study was done under the mentorship of Dr. Christopher Ogilvie and Dr. Ajit Thomas with a lot of amazing collaborators. So since the pipeline approval for treatment of aneurysms in 2011, it has become one of the most important treatment modalities for intracranial aneurysms. The main concern is when the pipeline spans a branch, there's always concern of a branch occlusion and subsequent ischemic stroke. And that's one of the main limitations that it was only approved for ICA below the level of the PCOM. And also one of the main limitations why it's not used very often for treatment of puss or circulation aneurysms. There is few studies that look into the outcome of the branches when covered by the pipeline in the anterior circulation. And it showed that in branches like the ophthalmic and PCOM, the risk of branch occlusion is significantly higher than the anterior coroidal. However, none of them was symptomatic. And from here came the concept of collateral supply versus end arteries. So in branches like the ophthalmic artery and the PCOM, where there's a lot of collaterals, these tend to occlude much more often than the anterior coroidal, which is considered as an end arteries. And in this situation, the pressure gradient in these end arteries is much higher and that what keeps the branch open. So in this study, we wanted to assess this relationship in the posterior circulation and look into what factors actually can predict branch occlusion and ischemic complications. We collected data from eight major academic centers in the United States, Canada, and Europe. And we looked into factors related to the patient aneurysm procedure and outcomes. So branch coverage was assessed during the procedure. Branch occlusion was assessed at the last follow-up, and only complete occlusion was considered. All the vessels in the posterior circulation were included, including the PCA and the VERT, which are not technically considered as branches, but can be also covered by the pipeline. Since the perforators are really hard to see on the DSA, the possibility of perforator occlusion was still considered, but we did not attempt to assess them during the procedure itself. And also, each branch was considered as a separate entity. For the ischemic complications, any ischemic complication from the date of procedure to the date of last follow-up was included. Ischemic complication we consider symptomatic if the patient reported symptoms or signs related to the territory involved. There was a total of 129 procedures and 131 aneurysms. Most of the patients presented with some form of neurologic deficit. Most of the aneurysms were fusiform. Most of them were located in the basilar and followed by the VERT. The median number of pipeline placed was one. Adjunctive coding was used in one-third of the procedures. At the median follow-up of 11 months, complete or near-complete occlusion was achieved in 78% of the aneurysms. For the cover branch, in most of the procedures, there was around 80% of the procedures, there was a cover branch with a median number of cover branch of two. We noticed that there was a significantly higher rate of branch occlusion for the VERT and the PCA compared to the PICA, ICA, and SCA, however, most of them were asymptomatic. There was also a significantly higher rate of occlusion if the patient was asymptomatic at the beginning, which we think also due to higher number of collaterals at presentation. We also looked into the ischemic complications, so we found that 22.5% of the procedure were complicated by ischemic complications, however, most of them were asymptomatic. Symptomatic ones were 13.2%, and permanent symptomatic was only an 8.5%. Only one out of these 11 permanent symptomatic actually was related to the branch occlusion. So when we looked into independent predictors, intraaneurysm thrombosis was associated with a significantly higher risk of thromboembolic complications. Also interestingly, non-smokers had a higher risk of thromboembolic complications, but there was no significant correlation between branch occlusion and rate of ischemic complications. This is one of the illustrated cases. We had a 55-year-old female who had a small basilar tib aneurysm. A pipeline was placed from the basilar into the left PCA, spanning the bilateral SCA and the right PCA. At four months, there was a complete occlusion of the right PCA. Both SCAs remained open, and the patient was neurologically intact. The conclusion of the study is similar to the anterior circulation. The end arteries, including the pica, ica, and SCA, tend to remain open after coverage with the pipeline, and this, as we think, is related to the high-pressure gradient, while the VERT and the PCAs tend to occlude much higher than the end arteries, and this is due to rich collateral supply. However, most of them is asymptomatic. And we noticed that ica had a high rate of thromboembolic complications following occlusion compared to other branches, but this might also be limited by the small number of cases. Thank you very much. Thank you.

branch occlusion

ischemic complications

pipeline embolization device

posterior circulation aneurysms

intracranial aneurysms