Comparison of surgical and endovascular approaches in the management of multiple intracranial aneurysms

Application of zone classification in multiple intracranial aneurysmal subarachnoid hemorrhage treatment strategies

Background

The options of surgical approach and treatment stage are two challenging treatment strategy issues with multiple intracranial aneurysmal subarachnoid hemorrhage (MIA-SAH).

Methods

We retrospectively analyzed data from patients with MIA-SAH who underwent surgery in our center between January 1, 2014 and September 1, 2022. To define "zone classification", the cranial cavity was divided into four zones by the planes of cerebral falx and tentorium cerebelli. Aneurysms isolated to one zone were defined as zone classification I; those crossing two zones were defined as zone classification II; those crossing three zones were defined as zone classification III; and those crossing four zones were defined as zone classification IV. General and aneurysmal-related characteristics of patients with different zone classifications were collected and compared between two surgical approaches. Multivariate logistic regression analysis was used to identify factors independently associated with multistage treatment options.

Results

A total of 226 patients with 523 aneurysms were included. The proportion of patients undergoing endovascular treatment increased with higher zone classification (I: 85.4%; II: 94.0%; III: 100.0%; IV: 100.0%). The proportion of patients receiving one-stage treatment decreased with higher zone classification (I: 60.2%; II: 33.6%; III: 0.0%; IV: 0.0%). Compared with patients undergoing microsurgical clipping, more patients undergoing endovascular treatment had zone classification II-IV (56.9% vs. 31.8%, p = 0.025). Zone classification II-IV (odds ratio [OR] = 3.821, 95% confidence interval [CI]: 2.041-7.154, p < 0.001), endovascular treatment (OR = 8.756, 95% CI: 2.589-29.609, p < 0.001), and size of all unruptured aneurysms <3 mm (OR = 4.531, 95% CI: 2.315-8.871, p < 0.001) were each independently associated with multistage treatment.

Conclusions

Zone classification provides a new idea in MIA-SAH treatment strategies, especially regarding surgical approach and treatment stage options.

Quantitative Evaluation of Hemodynamic Changes After Multiple Intracranial Aneurysms Occlusion Using Computational Fluid Dynamics

OBJECTIVE

Multiple intracranial aneurysms (MIA) are prevalent. This study conducted hemodynamic calculations on MIA to analyze the effects of occlusion of the internal carotid artery (ICA) and middle cerebral artery (MCA) aneurysms on the hemodynamics of other arteries, as well as the issue of the treatment order for these aneurysms.

METHODS

The models of 9 patients with MIA were selected for the study. A computational fluid dynamics model combining 1-dimension and 3-dimension was used to obtain the vascular flow pattern and wall pressure.

RESULTS

There was increased pressure at the MCA and anterior cerebral artery (ACA) after occlusion of the aneurysm at the ICA. However, the pressure at the ICA has hardly changed after the aneurysm occlusion at the MCA. Occlusion of the aneurysm of different sizes at the MCA had almost no impact on the pressure at the ICA and ACA. For small aneurysm, the pressure of the ACA and MCA increases with decreasing size of the aneurysm at the ICA. After occlusion of a large aneurysm at the ICA, the impact on the pressure of the ACA and MCA is almost the same as after occlusion of a medium-sized aneurysm.

CONCLUSIONS

If the treatment order of ICA and MCA aneurysms cannot be determined based on patient factors and aneurysm characteristics, the MCA aneurysm should be treated as a priority.

Multiple fusiform and saccular aneurysms in a person living with Human Immunodeficiency Virus

Cerebral aneurysms secondary to human immunodeficiency virus vasculopathy are a diagnosis by exclusion and its mechanism is unknown. We report on a 21-year-old male with human immunodeficiency virus infection and suboptimal virological control, despite highly active antiretroviral therapy. An incidental discovery of multiple cerebral aneurysms occurred in this patient, who initially presented with signs of disorientation, acute psychosis, and a history of blunt cranial trauma. A non-contrasted computerized tomography scan of the encephalon showed no intracranial hemorrhage but multiple cerebral (saccular and fusiform) aneurysms. Subsequently, a non-urgent computerized tomography angiogram of the cerebral vasculature corroborated the existence of multiple cerebral aneurysms. Despite investigation, no secondary etiological factors for the aneurysmal condition were identified. The multitude of cerebral aneurysms was consequently ascribed to human immunodeficiency virus-associated vasculopathy. The patient was managed conservatively. At discharge, he was lucid and apsychotic. A unique aspect of the case is the presence of both fusiform and saccular cerebral aneurysms.

Endovascular treatment strategies and a new classification for multiple aneurysms of the ipsilateral ophthalmic segment of the internal carotid artery

OBJECTIVE

Aneurysms occurring in the ophthalmic segment (C6) of the internal carotid artery (ICA) have complex anatomy. This poses a challenge for the use of traditional open surgery, which is gradually being replaced by endovascular treatment (EVT). However, multiple aneurysm (MA) EVT, especially in MAs occurring ipsilaterally, has not been specifically described or discussed. The present study aimed to propose a more concise clinical classification standard for ipsilateral C6 ICA MAs and report on the clinical experience with EVT.

METHODS

The cases of 18 patients with ipsilateral C6 ICA MAs treated with EVT were retrospectively reviewed. The treatment results and procedure-related complications were recorded, and clinical and angiographic follow-ups were performed at least six months after surgery.

RESULTS

A total of 38 ipsilateral C6 ICA aneurysms were treated during the study period and classified into four main types and six total subtypes based on anatomical features. There was a failure to coil through the stent in one aneurysm, while the remaining 37 were successfully treated using various EVT methods. Of these, 36 were completely concluded. One aneurysm had a size reduction, and one had no changes during the angiographic follow-up. All Tubridge flow diverter stents were patent. All patients achieved satisfactory clinical outcomes and were independent at the final follow-up.

CONCLUSION

EVT may be safe and feasible for the treatment of C6 ICA MAs. Traditional stent-assisted coiling methods, the Willis covered stent, and the double-layered low-profile visualized intraluminal support stent all achieved favorable results. The flow diverter stent is also considered a safe and efficient option for selected aneurysms, but the visual deficit risk should be considered. The present study introduces a new EVT classification option based on the anatomical features of an aneurysm.

Surgical Resection and Clipping of an Atherosclerotic Partially Calcified Middle Cerebral Artery Trifurcation Aneurysm with Clipping of an Anterior Communicating Artery Aneurysm: 2-Dimensional Operative Video

It is estimated within the western population that 10%-13% of patients possess multiple intracranial aneurysms¹ and are linked to certain risk factors. Thrombotic aneurysms are a rare subgroup of complex aneurysms characterized by an organized intraluminal thrombus.^2,3 They differ from typical saccular aneurysms in terms of morphology, natural history, symptomatology, and difficulty in treatment with conventional strategies.^2,4 The risk of rupture is poorly characterized and assumed to be comparable with that of nonthrombotic aneurysms.² A subset of thrombotic aneurysms can be treated surgically with conventional clipping, and direct clipping has been associated with the best surgical outcome.² Despite its safety, endovascular treatment is associated with a high risk of recurrence and retreatment compared with surgical treatment,⁵ with recanalization rates up to 5× higher compared with nonthrombosed aneurysms.^6,7 A 64-year-old male presented with headaches and dizziness for 6 months. He was neurologically intact. Imaging revealed a calcified thrombosed right middle cerebral artery aneurysm and an anterior communicating artery aneurysm, both of which underwent clipping. The patient consented to the procedure. Preservation of blood flow in branch arteries in thrombosed aneurysms is challenging. Thrombectomy and clip reconstruction in such cases can occlude the branch vessels, compromising blood flow. Achieving adequate proximal control and meticulous dissection of the branches is necessary before reconstruction. We present a 2-dimensional video demonstrating the surgical steps of clipping and reconstruction of the giant thrombosed middle cerebral artery aneurysm. Complete occlusion was achieved, and the patient tolerated the operation well with an uneventful postoperative course.

Noncurative microsurgery for cerebral aneurysms: a systematic review and meta-analysis of wrapping, residual, and recurrence rates

OBJECTIVE

Microsurgery for cerebral aneurysms is called definitive, yet some patients undergo a craniotomy that results in noncurative treatment. Furthermore, the overall rate of noncurative microsurgery for cerebral aneurysms is unclear. The objective of this study was to complete a systematic review and meta-analysis to quantify three scenarios of noncurative treatment: aneurysm wrapping, postclipping remnants, and late regrowth of completely obliterated aneurysms.

METHODS

A PRISMA-guided systematic literature review of the MEDLINE and Cochrane Library databases and meta-analysis was completed. Studies were included that detailed rates of aneurysm wrapping, residua confirmed with imaging, and regrowth after confirmed total occlusion. Pooled rates were subsequently calculated using a random-effects model. An assessment of statistical heterogeneity and publication bias among the included studies was also completed for each analysis, with resultant I2 values and p values determined with Egger's test.

RESULTS

Sixty-four studies met the inclusion criteria for final analysis. In 41 studies, 573/15,715 aneurysms were wrapped, for a rate of 3.5% (95% CI 2.7%-4.2%, I2 = 88%). In 43 studies, 906/13,902 aneurysms had residual neck or dome filling, for a rate of 6.4% (95% CI 5.2%-7.6%, I2 = 93%). In 15 studies, 71/2568 originally fully occluded aneurysms showed regrowth, for a rate of 2.1% (95% CI 1.2%-3.1%, I2 = 58%). Together, there was a total rate of noncurative surgery of 12.0% (95% CI 11.5%-12.5%). Egger's test suggested no significant publication bias among the studies. Meta-regression analysis revealed that the reported rate of aneurysm wrapping has significantly declined over time, whereas the rates of aneurysm residua and recurrence have not significantly changed.

CONCLUSIONS

Open microsurgery for cerebral aneurysm results in noncurative treatment approximately 12% of the time. This metric may be used to counsel patients and as a benchmark for other treatment modalities. This investigation is limited by the high degree of heterogeneity among the included studies.

Development and validation of a novel nomogram to predict aneurysm rupture in patients with multiple intracranial aneurysms: a multicentre retrospective study

Background and purpose

Approximately 15%–45% of patients with unruptured intracranial aneurysms have multiple intracranial aneurysms (MIAs). Determining which one is most likely to rupture is extremely important for treatment decision making for MIAs patients. This study aimed to develop and validate a nomogram to evaluate the per-aneurysm rupture risk of MIAs patients.

Methods

A total of 1671 IAs from 700 patients with MIAs were randomly dichotomised into derivation and validation sets. Multivariate logistic regression analysis was used to select predictors and construct a nomogram model for aneurysm rupture risk assessment in the derivation set. The discriminative accuracy, calibration performance and clinical usefulness of this nomogram were assessed. We also developed a multivariate model for a subgroup of 158 subarachnoid haemorrhage (SAH) patients and compared its performance with the nomogram model.

Results

Multivariate analyses identified seven variables that were significantly associated with IA rupture (history of SAH, alcohol consumption, female sex, aspect ratio >1.5, posterior circulation, irregular shape and bifurcation location). The clinical and morphological-based MIAs (CMB-MIAs) nomogram model showed good calibration and discrimination (derivation set: area under the curve (AUC)=0.740 validation set: AUC=0.772). Decision curve analysis demonstrated that the nomogram was clinically useful. Compared with the nomogram model, the AUC of multivariate model developed from SAH patients had lower value of 0.730.

Conclusions

This CMB-MIAs nomogram for MIAs rupture risk is the first to be developed and validated in a large multi-institutional cohort. This nomogram could be used in decision-making and risk stratification in MIAs patients.

Rupture risk assessment for multiple intracranial aneurysms: why there is no need for dozens of clinical, morphological and hemodynamic parameters

Introduction:

A multitude of approaches have been postulated for assessing the risk of intracranial aneurysm rupture. However, the amount of potential predictive factors is not applicable in clinical practice and they are rejected in favor of the more practical PHASES score. For the subgroup of multiple intracranial aneurysms (MIAs), the PHASES score might severely underestimate the rupture risk, as only the aneurysm with the largest diameter is considered for risk evaluation.

Methods:

In this study, we investigated 38 patients harboring a total number of 87 MIAs with respect to their morphological and hemodynamical characteristics. For the determination of the best suited parameters regarding their predictive power for aneurysm rupture, we conducted three phases of statistical evaluation. The statistical analysis aimed to identify parameters that differ significantly between ruptured and unruptured aneurysms, show smallest possible correlations among each other and have a high impact on rupture risk prediction.

Results:

Significant differences between ruptured and unruptured aneurysms were found in 16 out of 49 parameters. The lowest correlation were found for gamma, aspect ratio (AR1), aneurysm maximal relative residence time (Aneurysm_RRT_max) and aneurysm mean relative residence time. The data-driven parameter selection yielded a significant correlation of only two parameters (AR1 and the Aneurysm_RRT_max) with rupture state (area under curve = 0.75).

Conclusion:

A high number of established morphological and hemodynamical parameters seem to have no or only low effect on prediction of aneurysm rupture in patients with MIAs. For best possible rupture risk assessment of patients with MIAs, only the morphological parameter AR1 and the hemodynamical parameter Aneurysm_RRT_max need to be included in the prediction model.

Microsurgical clipping of multiple cerebral aneurysms in the acute phase of aneurysmal subarachnoid hemorrhage through a minipterional approach: The Chilean experience

OBJECTIVE

The minipterional craniotomy (MPTc) has been widely accepted as a minimally invasive alternative to the pterional approach for the treatment of certain small non-ruptured anterior circulation aneurysms. The aim of this study was to determine the effectiveness and safety of the MPTc in the context of a complex and potentially harmful scenario: acute onset of subarachnoid hemorrhage (SAH) in patients harboring multiple intracranial aneurysms (MIA).

METHODS

Patients harboring MIA clipped through a unilateral MPTc were selected from four retrospective databases of four high-volume neurosurgical centers. Patients with a Hunt & Hess score 4 or 5 were not considered candidates for clipping through a MPTc. Medical records and radiological images were retrospectively reviewed. Epidemiological, clinical and radiological data, as well as short-term outcome (modified Rankin scale at 6 month-follow-up) were analyzed.

RESULTS

16 patients harboring 33 aneurysms (16 ruptured, 17 non ruptured) met the inclusion criteria. Each aneurysm size was 5.7 ± 2.1 mm (range 3-11). 12 out of 33 aneurysms were located in the middle cerebral artery (MCA). Anterior communicating (ACom) and MCA aneurysms were the aneurysm locations most commonly ruptured (5 each, 62 %). Complete occlusion was achieved in 32 aneurysms (97 %) and near-complete occlusion in 1 (3%). 13 patients (93 %) were independent at 6 month-follow-up. Mortality rate was 0%. Complications included 1 cerebrospinal-fluid leakage.

CONCLUSION

When indicated (Hunt Hess < 4), performing a MPTc is safe and effective in aSAH cases with multiple aneurysms.

Outcome of Microsurgical Clipping for Multiple Versus Single Intracranial Aneurysms: A Single-Institution Retrospective Comparative Cohort Study

OBJECTIVE

To evaluate the results of microsurgical clipping for single intracranial aneurysm (SIA) and multiple intracranial aneurysms (MIA) and compare the outcomes.

METHODS

All patients who underwent surgery for intracranial aneurysm (IA) at our institution over a 3-year period (June 2013 to May 2016) were included in this study.

RESULTS

A total of 157 patients with 225 IAs were included. Forty-one of these patients had MIA (109 IAs, mean, 2.7 ± 1.2; range, 2-7), and remaining 116 had SIA. In the patients with MIA, all aneurysms were secured during the same admission whenever possible. Depending on the locations of the IAs and condition of brain during surgery (tense/lax), all aneurysms were secured on same day (in a single session, single or multiple craniotomy in 28 patients) or on different days (multiple sessions in 13 patients). Postoperative control angiography (DSA) before discharge could be done for 216 aneurysms (MIA, n = 105; SIA, n = 111). Successful occlusion of the aneurysm from circulation was noted in 96.2% (101/105) of MIA and 93.7% (104/111) of SIA. Follow-up of 6 months or longer was available for 146 patients. A modified Rankin Scale score ≤2 was considered a good outcome. Univariate analysis of the entire group revealed no significant difference in clinical outcomes between patients with SIA and MIA both at discharge (good outcome: MIA, 82.9%; SIA, 93.1%; P = 0.068) and at a final follow-up of ≥6 months (good outcome: MIA, 87.2%; SIA, 94.4%; P = 0.164). Clipping for MIA was not associated with poor outcome in multivariate analysis.

CONCLUSIONS

Comparable clinical outcomes and high rates of complete aneurysm occlusion following microsurgical clipping can be expected in patients with SIA and patients with MIA.

Coil embolisation of multiple cerebral aneurysms with lateral type I persistent primitive trigeminal artery: A case report and literature review

The primitive trigeminal artery is an anastomotic vessel of the carotid-basilar artery system that occurs only transiently during the embryonic period. Persistent primitive trigeminal artery occurs in approximately 0.1-0.6% of the population. Here, we report the case of a 60-year-old woman with Fisher II grade subarachnoid haemorrhage. Computed tomography angiography demonstrated a lateral, Saltzman type I persistent primitive trigeminal artery with three cerebral aneurysms, including one anterior communicating artery aneurysm, one suspicious right anterior choroidal artery aneurysm and one distal basilar artery aneurysm supplied by the persistent primitive trigeminal artery. All three aneurysms were treated with coil embolisation. At the 8-month follow-up, the anterior communicating artery aneurysm had a neck remnant, the other two aneurysms exhibited complete occlusion. Persistent primitive trigeminal artery with multiple cerebral aneurysms is extremely rare, and only seven cases of persistent primitive trigeminal artery with multiple cerebral aneurysms have previously been reported in publications that included information on treatment. Most aneurysms were treated by open surgery. This is the first report of coil embolisation treatment of multiple aneurysms in persistent primitive trigeminal artery patients with follow-up results, and provides relevant and valuable information about the persistent primitive trigeminal artery and the endovascular treatment of multiple aneurysms in persistent primitive trigeminal artery patients.

Concomitant ruptured anterior circulation and unruptured posterior circulation aneurysms: Treatment strategy and review of literature

Basilar artery apex or bifurcation is the most common location for aneurysms arising from posterior cerebral circulation. Reports of unruptured aneurysms of the basilar bifurcation associated with ruptured anterior circulation aneurysms are rare. The presence of multiple intracranial aneurysms poses a significantly high risk to management than a single aneurysm due several factors involved. Surgical management is considered the best treatment modality for most aneurysmal types and location with quite a few limitations when applicable. Authors have conducted a literature review of anterior and posterior circulation concomitant aneurysms and report their own experience with a case of anterior communicating artery blister type aneurysmal rupture presented with the symptoms and signs of subarachnoid hemorrhage concomitant with an unruptured basilar artery bifurcation aneurysm. Moreover, the anomalous origin of thalamoperforators at the basilar apex instead of the posterior cerebral artery makes it reasonably challenging for the microsurgical clipping. Discussed is the clinical presentation, radiological studies obtained, surgical approach utilized with an adequate exposure of the entire circle of Willis as well as the critical decision making when managing these challenging cases.

Residual Cerebral Aneurysms After Microsurgical Clipping: A New Scale, an Agreement Study, and a Systematic Review of the Literature

OBJECTIVE

The surgical repair of a cerebral aneurysm does not always lead to complete occlusion. A standardized repeatable method of reporting results of surgical clipping is desirable. Our purpose was to systematically review methods of classifying aneurysm remnants, provide a new scale with precise definitions of categories, and perform an agreement study to assess the variability in adjudicating remnants after aneurysm clipping.

METHODS

A systematic review was performed to identify ways to report angiographic results of surgical clipping between 1963 and 2017. Postclipping angiographic results of 43 patients were also independently evaluated by 10 raters of various experience and backgrounds using a new 4-category scale. Agreement between responses were analyzed using κ statistics.

RESULTS

The systematic review yielded 63 articles with 37 different nomenclatures using 2-6 categories. The reliability of judging the presence of an aneurysm remnant on catheter angiography was studied only twice, with only 2 raters each time, with contradictory results. Interobserver agreement using the new 4-category scale was moderate (κ = 0.52; 95% confidence interval, 0.43-0.62) for all observers, but improved to substantial (κ = 0.62; 95% confidence interval, 0.47-0.76) when results were dichotomized (grade 0/1 vs. 2/3).

CONCLUSIONS

Various classification schemes to evaluate angiographic results after surgical clipping exist in the literature, but they lack standardization. Adjudication using fewer, better defined categories may yield more reliable agreement.

Is Single Low-Profile Visualized Intraluminal Support (LVIS)-Assisted Coiling of Wide-Necked Ruptured Multiple Intracranial Aneurysms in One Stage Feasible?

OBJECTIVE

There is no previous reports available on stent-assisted coiling of ruptured multiple intracranial aneurysms using single Low-Profile Visualized Intraluminal Support (LVIS) in one stage. In the present study, we investigated the efficacy and feasibility of using single LVIS to bridge multiple intracranial aneurysms in one stage.

METHODS

From April 2014 to August 2016, 24 patients treated with single LVIS to bridge 2 aneurysms in one stage were reviewed. The aneurysm morphology, clinical outcome, angiographic results, progressive occlusion, recurrence, and procedure-related complications were analyzed retrospectively.

RESULTS

In the present study, middle term clinical outcome showed that 9 patients were had a modified Rankin Scale (mRS) score of 0, 11 patients had mRS 1, and 4 patients had mRS 2. A total of 20 patients (83.3%) achieved a good outcome, 4 patients (16.7%) had poor outcomes, and 7 of 18 patients (38.9%) displayed improved clinical neurologic status in long-term follow-up. Immediate angiographic results postprocedure showed Raymond Scale (RS) I in 33 aneurysms (68.8%), RS II in 11 aneurysms (22.9%), and RS III in 4 aneurysms (8.3%). The angiographic follow-up results showed RS I in 41 aneurysms (85.4%), RS II in 5 aneurysms (10.4%), and RS III in 2 aneurysms (4.2%). Of 15 incomplete occlusion aneurysms postprocedure, 10 aneurysms (66.7%) achieved to progressed occlusion on follow-up imaging, and no recanalization or mortality occurred in this group.

CONCLUSIONS

Single LVIS bridging wide-neck ruptured multiple intracranial aneurysms was effective and feasible in one stage. However, the procedure-related complications should be emphasized and long-term follow-up requires further evaluation.