Microsurgical and endovascular treatment of un-ruptured cerebral aneurysms by European hybrid neurosurgeons to balance surgical skills and medical staff management

Integrating endovascular techniques into established open neurosurgery practice: a temporal analysis of treatment evolution in a dual-trained neurosurgical unit

OBJETIVE

In Europe, units with Dual-trained Neurovascular Surgeons (DTNS) skilled in both open neurosurgery (ON) and endovascular neurosurgery (EN) are scarce. For instance, in Spain, our unit is unique within the public health system, where all neurovascular procedures are carried out by DTNS. Our study aims to evaluate the evolution in treating ruptured intracranial aneurysms (rICAs) and assess the impact of this evolution on clinical outcomes.

METHODS

A retrospective cohort study was performed on rICAs treated in our unit from October 2012 to June 2023. We reviewed clinical and radiological data to analyze the evolution of ON and EN over time, as well as their impact on patient outcomes. Univariate, multivariate, and mixed-effects models were utilized to discern temporal changes.

RESULTS

The modified Fisher Scale (mFS) and the modified World Federation of Neurological Surgeons scale (mWFNS) showed strong correlation with the outcome at 6 months outcomes, both with p < 0.00001. However, the surgical intervention method, ON versus EN, did not significantly affect outcomes (p > 0.85). In adjusted multivariate logistic regression, mFS (-1.579, p: 0.011) and mWFNS (-0.872, p < 0.001) maintained their significance. rICAs location was significant when comparing ON to EN p = 0.0001. A significant temporal trend favored the selection of EN p = 0.0058). Mixed-effects time series modeling indicated that while patient characteristics and rICA specifics did not predict treatment choice, the year of treatment was significantly correlated (0.161, p = 0.002). Logistic regression with interaction terms for time and treatment type did not produce significant results.

CONCLUSION

Our findings suggest that despite an increased adoption of EN techniques, there has been no change in patient outcomes. Even with the rise of EN, our unit continues to perform ON for a higher proportion of rICAs than most national hospitals. We propose that a "dual approach" offers advantages in a patient individualized treatment decision protocol in the European context.

Systematic Review and Meta-Analysis of Endovascular Therapy Effectiveness for Unruptured Saccular Intracranial Aneurysms

Background

Currently, endovascular treatment of intracranial aneurysms (ICAs) is limited by low complete occlusion rates. The advent of novel endovascular technology has expanded the applicability of endovascular therapy; however, the superiority of novel embolic devices over the traditional Guglielmi detachable coils (GDCs) is still debated. We performed a systematic review of literature that reported Raymond-Roy occlusion classification (RROC) rates of modern endovascular devices to determine their immediate and follow-up occlusion effectiveness for the treatment of unruptured saccular ICAs.

Methods

A search was conducted using electronic databases (PUBMED, Cochrane, ClinicalTrials.gov, Web of Science). We retrieved studies published between 2000-2022 reporting immediate and follow-up RROC rates of subjects treated with different endovascular ICA therapies. We extracted demographic information of the treated patients and their reported angiographic RROC rates.

Results

A total of 80 studies from 15 countries were included for data extraction. RROC rates determined from angiogram were obtained for 21,331 patients (72.5% females, pooled mean age: 58.2 (95% CI: 56.8-59.6), harboring 22,791 aneurysms. The most frequent aneurysm locations were the internal carotid artery (46.4%, 95% CI: 41.9%-50.9%), the anterior communicating artery (26.4%, 95% CI: 22.5%-30.8%), the middle cerebral artery (24.5%, 95% CI:19.2%-30.8%) and the basilar tip (14.4%, 95% CI:11.3%-18.3%). The complete occlusion probability (RROC-I) was analyzed for GDCs, the Woven EndoBridge (WEB), and flow diverters. The RROC-I rate was the highest in balloon-assisted coiling (73.9%, 95% CI: 65.0%-81.2%) and the lowest in the WEB (27.8%, 95% CI:13.2%-49.2%). The follow-up RROC-I probability was homogenous in all analyzed devices.

Conclusions

We observed that the coil-based endovascular therapy provides acceptable rates of complete occlusion, and these rates are improved in balloon-assisted coils. Out of the analyzed devices, the WEB exhibited the shortest time to achieve >90% probability of follow-up complete occlusion (~18 months). Overall, the GDCs remain the gold standard for endovascular treatment of unruptured saccular aneurysms.

Trends in the Age of Patients Treated for Unruptured Intracranial Aneurysms from 1990 to 2020

BACKGROUND

The decision for treatment for unruptured intracranial aneurysms (UIAs) is often difficult. Innovation in endovascular devices have improved the benefit-to-risk profile especially for elderly patients; however, the treatment guidelines from the past decade often recommend conservative management. It is unknown how these changes have affected the overall age of the patients selected for treatment. Herein, we aimed to study potential changes in the average age of the patients that are being treated over time.

METHODS

A systematic search of the literature was performed to identify all studies describing the age of the UIAs that were treated by any modality. Scatter diagrams with trend lines were used to plot the age of the patients treated over time and assess the presence of a potential significant trend via statistical correlation tests.

RESULTS

A total of 280 studies including 83,437 UIAs treated between 1987 and 2021 met all eligibility criteria and were entered in the analysis. Mean age of the patients was 55.5 years, and 70.7% were female. There was a significant increasing trend in the age of the treated patients over time (Spearman r: 0.250; P < 0.001), with a 1-year increase in the average age of the treated patients every 5 years since 1987.

CONCLUSIONS

The present study indicates that based on the treated UIA patient data published in the literature, older UIAs are being treated over time. This trend is likely driven by safer treatments while suggesting that re-evaluation of certain UIA treatment decision scores may be of great interest.

Is it time to rethink microsurgical training for the treatment of intracranial aneurysms in Australia?

BACKGROUND

Case volume and complexity for microsurgical treatment of cerebral aneurysms have changed due to the growing use of endovascular therapy in clinical practice. The authors sought to quantify the clinical exposure of Australian neurosurgery trainees to cerebral aneurysm microsurgery.

METHODS

This observational, retrospective cross-sectional study examined the Australian National Hospital Morbidity database for all admissions related to microsurgical and endovascular treatment of aneurysmal subarachnoid haemorrhage (aSAH) and unruptured intracranial aneurysms (UIAs) for the years 2008 to 2018. Procedural volumes were compared with neurosurgical trainee figures to investigate the rate of procedural exposure relative to the neurosurgical workforce.

RESULTS

A total of 8,874 (41.6%) microsurgical procedures (3,662 for aSAH, 5,212 for UIAs), and 12,481 (58.4%) endovascular procedures (6,018 for aSAH, 6,463 for UIAs) were performed. Trainee exposure to microsurgery in aSAH declined from 9.1 to 7.3 cases per trainee per annum (mean 7.7), with case complexity confined mostly to simple anterior circulation aneurysms. There are significant state-by-state differences in the preferred treatment modality for aSAH. During the same study period, the number of microsurgical cases for UIAs increased (from 8.9 to 13.5 cases per trainee per annum, mean 11.0). Significantly more endovascular procedures are performed than microsurgery (10.7 to 17.0, mean 12.7 cases, for aSAH; 8.0 to 21.5, mean 13.7 cases, for UIAs).

CONCLUSIONS

Trainee exposure to open aneurysm surgery for aSAH have significantly declined in both case volume and complexity. There is an overall increase in the number of surgeries for elective aneurysms, but this varies widely from state-to-state.

Mortality among patients treated for aneurysmal subarachnoid hemorrhage in Eastern Denmark 2017-2019

OBJECTIVE

The aim of the study was to investigate (1) the 30-day, 3-month, and 12-month cumulative mortalities for patients who underwent aneurysm occlusion, and (2) the causes of death, and (3) the potential risk factors for death.

METHODS

All patients who underwent surgical clipping or endovascular treatment of a ruptured aneurysm at Copenhagen University Hospital, during the period of January 1, 2017-December 31, 2019, were included and followed up for 12 months. Data regarding vital status, causes of death, comorbidities, treatment, and clinical presentations on admission was collected. The absolute mortality risk was estimated as a function of time with a 95% confidence interval. The associations between potential risk factors and death were estimated as odds ratios with 95% confidence intervals using logistic regression models.

RESULTS

A total of 317 patients were included. The overall cumulative mortalities after 30 days, 3 months, and 12 months were 10.7%, 12.9%, and 16.1%, respectively. The most common cause of death was severe primary hemorrhage (52.9%), followed by infections (15.7%) and rebleeding (11.8%). WFNS score > 3 and Fisher score > 3 on admission, preprocedural hydrocephalus, and preprocedural rebleeding were found significantly associated with higher risk of death.

CONCLUSIONS

Considerable mortality was seen. Possible preventable causes accounted for approximately 22% of the deaths. The occurrence of both pre- and postprocedural rebleeding's indicates an opportunity of further improvement of the mortality by (1) further reduction of time from aSAH to aneurysm occlusion and (2) continuous efforts in improving methods of aneurysm occlusion.