So next we have Justin Massatelli speaking on analysis of wide-necked aneurysms in the Barrow ruptured aneurysm trial. Okay. Thanks so much for having me. Only disclosure is that we're currently running a wide-necked aneurysm registry which is unrelated to the current study. So as background, ruptured wide-necked aneurysms are of clinical interest because they require more advanced techniques with possibly increased treatment risk. And although there's many studies that evaluate perhaps a single technology in isolation, there are a few studies that compare clipping and coiling and also surprisingly few studies that just look at clipping. So we thought that while we're performing our registry, we would take advantage of having some of the BRAT data to perform some analyses. So the questions that we had, how many ruptured aneurysms in BRAT had a wide neck and do they differ from narrow neck aneurysms? Did wide neck morphology result in different treatments? And how did clipping compare to coiling in both the intent to treat and as treated analyses? So everyone knows the methods of BRAT, but this was a randomized prospective trial. All patients with non-traumatic subarachnoid hemorrhage from 2003 to 2007, 471 patients were enrolled, 238 in the clip group and 233 in the coil group. Because there were no anatomic exclusion criteria, there were within the population, there were non-aneurysmal subarachnoid hemorrhages, there were subarachnoid hemorrhages related to AVMs and fistulas as well as atypical aneurysms and then finally saccular aneurysms which made up the vast majority. In terms of exclusions, particularly for this analysis, we excluded the atypical aneurysms, we excluded the non-aneurysmal subarachnoid hemorrhages, we excluded six patients who died before treatment and then we excluded about 30 patients who didn't have angiographic data to make, to measure the neck, that would be like a poorly timed CTA bolus. This resulted with 327 patients for the analysis, 177 wide and 150 narrow. So in terms of measuring the aneurysm neck, primarily was done on CTA, sometimes DSA and we used the most common definition which is that one either an aneurysm neck with a maximum width of four or greater or a dome to neck ratio less than two. This will generate three populations of aneurysms, those will be the large aneurysms with the large neck, smaller aneurysms with a dome to neck ratio less than two or kind of medium sized aneurysms with both features. In terms of outcome, good clinical outcome was modified Rankin scale zero to two and this was assessed by research nurses and the angiographic outcome was aneurysm obliteration, this was assessed by an independent radiologist. We did the intent to treat an as treated analysis similar to the Brad trials. For the results, just using these definitions, just over half of the aneurysms were classified as having a wide neck. In terms of the breakdown, about 25% of them had the absolute value of four millimeters, about 40% had the dome to neck ratio less than two and about 35% had both features. Within the wide necks, the average dome volume was seven millimeters, average neck width was four millimeters and the average dome to neck ratio was 1.7. When comparing narrow neck and wide neck aneurysms, the wide neck aneurysms tended to occur in older patients, they tended to occur in patients with worse presenting grade, about 25% poor grade versus about 13% poor grade. They tended to occur at the ICA other than the junction with the PCOM or the MCA and the basilar tip and also, I'll just point out that in terms of supplemental endovascular treatment, it was low in both groups in this trial and that's I think somewhat related to the time period that the trial was performed. Interestingly, wide neck aneurysms tended to have poor clinical outcome at all time points in comparison to narrow neck aneurysms, that was irrespective of their treatment. Okay, so did wide neck morphology influence treatment? So the wide necks were equally distributed in the assigned treatment but they were overrepresented in the actual treatment with 62% clipped versus 37% in the coiled group. And that was highly driven by over 75% of the patients in that coiled to clip crossover group that has been discussed extensively having a wide neck. In terms of the coiling versus clipping outcomes in the intent to treat analysis, there was not a statistical difference at any time point between the number of patients with modified rank and greater than 2. In terms of the as treated analysis, similarly there wasn't a difference in outcome at any time point. There may be a small signal in the data with slightly improved outcomes with coiling but this did not reach statistical significance. And then in terms of obliteration, there were lower rates of complete obliteration and higher rates of retreatment in the coiling cohort which mimics the BRAT trials. Okay, so the main findings. Using the standard definition of wide neck aneurysm, just over half of the ruptured aneurysms in BRAT had a wide neck. They were more likely to occur in older patients with worse presenting clinical grade, were more likely to occur at the MCA, Basler tip or the ICA other than the junction with the PCOM and they were associated with worse clinical outcomes at all time points. They were equally distributed in the treatment groups but they were overrepresented in the coiled to clip crossover group which made them overrepresented in the clipping cohort and the use of supplemental endovascular techniques were low in both the narrow and the wide neck cohort. Comparing clipping and coiling, there weren't differences in clinical outcome at any time point using the intent to treat or as treated analysis and the aneurysm obliteration rate was lower and retreatment rate higher in the coiling group. Okay, so the study has a number of limitations. There's the same principle limitations as BRAT. It's a single institution. There's a, there was a bias for coiling to clipping crossovers which has been, you know, discussed before. BRAT was not designed or powered to detect differences in the wide neck population. We measured the aneurysms on CTA, not DSA. There were low rates of balloon assisted coiling and stent assisted coiling in the trial and point number six is I think the most important which is that a decade of improved endovascular technology has occurred since the closing of the trial which will limit the applicability of the coiling versus clipping analysis. The strengths that I think of this paper are that one, it actually provides some natural history data on wide versus narrow neck aneurysms that I haven't seen discussed too much in the literature with the main point being that they actually do worse than narrow neck aneurysms despite their treatment. It sheds a little bit more light on the crossovers in BRAT and it actually provides us with some outcome data just on clipping of wide neck aneurysms that also is not reported well in the literature that a number of, you know, there's always many endovascular technologies being evaluated for wide neck aneurysms and this can be a clipping benchmark that could be discussed in comparison. That's it. Thanks so much. Thank you.

wide-necked aneurysms

Barrow ruptured aneurysm trial

treatment outcomes

coiling and clipping techniques

clinical outcomes