Subarachnoid Hemorrhage Outcomes in an Endovascular Right of First Refusal Neurosurgical Environment

BACKGROUND

Randomized controlled trials demonstrate that endovascular techniques yield improved outcomes compared with microsurgical approaches. However, not all patients are suitable candidates for endovascular management. This study aimed to determine if healthy patients managed microsurgically could achieve functional outcomes comparable to patients managed endovascularly.

METHODS

Patients treated for ruptured aneurysmal subarachnoid hemorrhage at 2 level 1 stroke centers from January 2012 through December 2020 were retrospectively reviewed. All cases were evaluated in an endovascular right of first refusal neurosurgical environment. We collected relevant clinical and follow-up data and created a generalized linear model to identify differences between patients treated endovascularly versus microsurgically. A propensity score model accounting for these differences was used to predict patient outcomes. Functional outcomes were independently assessed using the modified Rankin Scale (mRS) with good functional outcome defined as modified Rankin Scale score <3.

RESULTS

The study included 588 patients (211 microsurgical, 377 endovascular); median age was 58 years (interquartile range: 40-86 years); in-hospital mortality was 13%. Age, aneurysm size, and aneurysm location significantly predicted treatment modality (all P < 0.05). After greedy-type matching (210 microsurgical, 210 endovascular), patients managed microsurgically were less likely to be discharged home (odds ratio = 0.6, 95% confidence interval 0.4-0.9, P = 0.01). Functional differences disappeared over time; patients in the 2 treatment arms had similar functional outcomes at 3 months (odds ratio = 1.1, 95% confidence interval 0.7-1.8, P = 0.66) and 1 year after subarachnoid hemorrhage (odds ratio = 1.3, 95% confidence interval 0.8-2.1, P = 0.38).

CONCLUSIONS

In an endovascular right of first refusal neurosurgical environment, practitioners can treat patients who are not good endovascular candidates microsurgically and achieve functional outcomes comparable to patients managed endovascularly.

Frequency and risk factors for postoperative aneurysm residual after microsurgical clipping

OBJECTIVE

Aneurysm residuals after clipping are a well-known problem, but the course of aneurysm remnants in follow-up is not well studied. No standards or follow-up guidelines exist for treatment of aneurysm remnants. The aim of this study was to evaluate the risk factors for postoperative aneurysm remnants and their changes during follow-up.

METHODS

We performed a retrospective analysis of 666 aneurysms treated via clipping in our hospital from 2006 to 2016. Postoperative and follow-up angiographic data were analyzed for aneurysm remnants and regrowth. Clinical parameters and aneurysm-specific characteristics were correlated with radiological results.

RESULTS

The frequency of aneurysm residuals was 12% (78/666). Aneurysms located in the middle cerebral artery (p = 0.02) showed a significantly lower risk for incomplete aneurysm occlusion. Larger aneurysms with a diameter of 11-25 mm (p = 0.005) showed a significantly higher risk for incomplete aneurysm occlusion. Five patients underwent re-clipping during the same hospital stay. Remnants were stratified based on morphological characteristics into "dog ears" (n = 60) and "broad based" (n = 13). The majority of the "dog ears" stayed stable, decreased in size, or vanished during follow-up. Broad-based remnants showed a higher risk of regrowth.

CONCLUSIONS

A middle cerebral artery location seems to lower the risk for the incomplete clip occlusion of an aneurysm. Greater aneurysm size (11-25 mm) is associated with a postoperative aneurysm remnant. The majority of "dog-ear" remnants appear to remain stable during follow-up. In these cases, unnecessarily frequent angiographic checks could be avoided. By contrast, broad-based residuals show a higher risk of regrowth that requires close imaging controls if retreatment cannot be performed immediately.