Introduction:
Ruptured wide-neck aneurysms (WNAs) are difficult to treat and there is minimal literature comparing clipping to coiling. The Barrow Ruptured Aneurysm Trial (BRAT) is a prospective, randomized trial comparing clipping and coiling. We aimed to determine: 1) How many aneurysms had a wide neck? 2) Did wide-neck status influence treatment? 3) How did clipping compare to coiling for WNAs?
Methods:
This is a post-hoc analysis of WNAs within BRAT. Exclusion criteria from the original dataset (n=471) included non-saccular morphology (n=52), non-aneurysmal SAH (n=57), death before treatment (n=6), and insufficient angiographic data (n=29). A WNA was defined as 1) neck width 4 mm or greater; or 2) dome diameter to neck width ratio less than 2.
Results:
Of 327 patients, 177 (54.2%) had a wide neck. WNAs were more likely to occur in older patients (p=0.03) with worse clinical grade (p=0.02); were more likely to arise from the MCA, basilar tip, or ICA other than the junction with the PCoA (p=0.001); and were associated with worse clinical outcome (p=0.01 or less). WNAs were equally distributed in the assigned treatment groups (Clip 56.6% vs. Coil 51.8%, p=0.38), but were over-represented in the actual clipping cohort (Clip 62.4% vs. Coil 37.6%, p<0.0001). The majority of aneurysms (76.7%) in the coil-to-clip crossover cohort had a wide neck. There was no difference in clinical outcome in either the intent-to-treat analysis or as-treated analysis. The aneurysm obliteration rate was lower (p<0.0001) and retreatment rate higher (p<0.0001) in the actual coiling cohort.
Conclusions:
This study is the first to compare clipping and coiling of WNAs on a large scale. Wide-neck status significantly impacted treatment strategy favoring clipping. A wide aneurysm neck is an important morphological feature that can be used in selecting the best treatment modality, with clipping favored over coiling.
Patient Care:
Our research may impact how future patients with WNAs are treated. There are many methods by which a WNA can be treated. This research demonstrates that surgical clipping remains a good and durable option.
Learning Objectives:
By the conclusion of this session, participants should be able to: 1) Understand the frequency of ruptured WNAs 2) Understand how WNAs compare to narrow neck aneurysms 3) Understand how wide neck status impacted treatment in BRAT 4) Understand how clipping compared to coiling for WNAs within BRAT