Parent vessel occlusion for treatment of cerebral aneurysms: Is there still an indication? A series of 17 patients

Micro-WADA and balloon test occlusion for sacrifice of distal P2 aneurysm

Here we present a fusiform, partially thrombosed, previously ruptured aneurysm in the posterior cerebral artery that was treated with parent vessel sacrifice after a micro-WADA and micro-balloon test occlusion (video 1). These aneurysms pose treatment challenges due to their deep location, morphology, and potentially eloquent distal supply.1 2 Primary coiling, stent assisted coiling, or microsurgical clipping are often not viable options, whereas flow diversion, parent vessel sacrifice,3 or trapping with bypass are usually employed. Pharmacological provocative testing via a micro-WADA4 5 with or without a micro-balloon test occlusion is critical to establish whether the territory at risk has functional eloquence, although specific reports for using these techniques are limited. We describe the patient presentation, initial treatment attempt and failure, and our protocol for performing a micro-WADA/balloon test occlusion test.neurintsurg;jnis-2024-022058v3/V1F1V1Video 1 Micro wada for PCA aneurysm.

Exploring the latest findings on endovascular treatments for giant aneurysms: a review

Giant intracranial aneurysms represent a very challenging aspect of aneurysmal pathophysiology with very high mortality and morbidity if left untreated. Their variety in clinical presentation (subarachnoid hemorrhage, cranial nerve palsy, etc.) and pathological and imaging properties (location, anatomy, presence of collateral circulation) pose serious questions regarding the best treatment option. Admirable advances have been achieved in surgical techniques, while endovascular modalities with flow diversion techniques have become widely used. However, there is still lack of data regarding whether a single endovascular technique can be the universal treatment for such cases. In this review, we aim to summarize the current funds of knowledge concerning giant intracranial aneurysms and the role of endovascular management in their treatment.

Microsurgical and endovascular treatment of large and giant aneurysms of the anterior circulation: A systematic review

Introduction

Large and Giant intracranial aneurysms (LGIAs) have become the paradigm for which endovascular techniques do not provide satisfactory results. Yet, microsurgery is followed by non-negligible rates of morbimortality. This scenario may have changed since the introduction of flow-diversion devices.

Research question

Contemporary and standardised revision on microsurgical and endovascular results, with emphasis on anterior circulation LGIAs.

Materials and methods

A systematic literature search was conducted in two databases (PubMed and Embase) on treatment outcomes of LGIAs of the anterior circulation, after the introduction of flow-diverters 2008/01/01, till 2023/05/20. Small case series (<5 cases), series including >15% of posterior circulation aneurysms, and studies not reporting clinical and/or angiographic outcomes were excluded.

Results

44 relevant studies (observational cohorts) were identified, including 2923 LGIAs predominantly from anterior circulation. Mean follow-up 22 (±20) months. 1494 (51%) LGIAs were treated endovascularly and 1427 (49%) microsurgically. According to the random effects model, pooled rates of favourable clinical outcomes were 85.8% (CI 95% 82.6-88.4), complete occlusion 69.4% (CI 95% 63.7-7.46), complications 19.6% (CI 95%16-23.9) and mortality 5.6% (CI 95% 4.4-7.1). Focusing on type of treatment, occlusion rates are higher with microsurgical (842/993, 85% vs 874/1,299, 67%), although good outcomes are slightly more frequent with endovascular (1045/1,135, 92% vs 1120/1,294, 87%).

Discussion and conclusions

According to contemporary data about occlusion rates, functional outcomes, and complications, primary or secondary treatment of LGIAs of the anterior circulation seems justified. Microsurgical occlusion rates are higher in LGIAs. An expert consensus on reporting complications and management strategies is warranted.

Endovascular Parent Vessel Occlusion Versus Flow Diversion in the Treatment of Large and Giant Aneurysms: A Randomized Comparison

OBJECTIVE

Parent vessel occlusion (PVO) is a time-honored treatment for unclippable or uncoilable intracranial aneurysms. Flow diversion (FD) is a recent endovascular alternative that can occlude the aneurysm and spare the parent blood vessel. Our aim was to compare outcomes of FD with endovascular PVO.

METHODS

This is a prespecified treatment subgroup analysis of the Flow diversion in Intracranial Aneurysms trial (FIAT). FIAT was an investigator-led parallel-group all-inclusive pragmatic randomized trial. For each patient, clinicians had to prespecify an alternative management option to FD before stratified randomization. We report all patients for whom PVO was selected as the best alternative treatment to FD. The primary outcome was a composite of core-lab determined angiographic occlusion or near-occlusion at 3-12 months combined with an independent clinical outcome (mRS<3). Primary analyses were intent-to-treat. There was no blinding.

RESULTS

There were 45 patients (16.2% of the 278 FIAT patients randomized between 2011 and 2020 in 3 centers): 22 were randomly allocated to FD and 23 to PVO. Aneurysms were mainly large or giant (mean 22 mm) anterior circulation (mainly carotid) aneurysms. A poor primary outcome was reached in 11/22 FD (50.0%) compared to 9/23 PVO patients (39.1%) (RR: 1.28, 95% CI [0.66-2.47]; P = 0.466). Morbidity (mRS >2) at 1 year occurred in 4/22 FD and 6/23 PVO patients. Angiographic results and serious adverse events were similar.

CONCLUSIONS

The comparison between PVO and FD was inconclusive. More randomized trials are needed to better determine the role of FD in large aneurysms eligible for PVO.

Endovascular treatments of intracranial vertebral and internal carotid arteries dissections: An interactive systematic review and meta-analysis

INTRODUCTION

Management of intracranial artery dissection (IAD) remains elusive in medical practice. Intracranially, vertebral artery dissection (VAD) is more commonly encountered than internal carotid artery dissection (ICAD). Deconstructive (EVT-d) and reconstructive (EVT-r) endovascular techniques have been utilized to treat VAD and ICAD. This meta-analysis investigates the safety and efficacy of EVT-r and EVT-d in the management of VAD and ICAD.

METHODS

The literature was searched for all studies with consecutive patient series evaluating EVT-d or EVT-r for VAD or ICAD management. Baseline characteristics and outcomes were compared between EVT-r and EVT-d groups using the random-effect model and meta-regression approaches.

RESULTS

Overall, 1095 cases pooled from 56 studies were included. There was no statistically significant difference in baseline characteristics between VAD and ICAD. EVT-r was applied in 647 cases (59.1%) and EVT-d in the rest There was no statistical difference in the rate of procedural complications between EVT-r and EVT-d. Although EVT-d was significantly associated with higher rates of complete aneurysm occlusion (86.4%), lower rates of good clinical outcomes (72.1%) and higher mortality (15.1%) were achieved compared to EVT-r (70.2%, 83.3%, and 9.5%; respectively). The mortality rate was higher, and good clinical outcomes were less common in ruptured aneurysms. Ischemic presentation was statistically associated with poor outcomes (mRS 3-5) but low mortality. ICAD often tended to grow following treatment and resulted in poor neurological outcomes.

CONCLUSIONS

IAD has favorable outcomes when treated appropriately. Novel reconstructive endovascular techniques are promising and should be integrated well in endovascular practice. Further studies are warranted.

Clinical characteristics and individualized treatment of intracranial aneurysms in young adults: a single-center experience

This study aimed to investigate the clinical characteristics of intracranial aneurysms in young adults and summarize our treatment experiences. We performed a retrospective review of young patients (15-24 years old) with intracranial aneurysms examined in the Fifth Ward of the Neurosurgery Department of Tianjin Huanhu Hospital between January 2015 and November 2022. Data was reviewed for age, sex, presentation, type and size, treatment modalities, location, postoperative complications, and clinical and imaging outcomes. Among the 23 patients, there were 11 males and 12 females (1:1.09). Their presentations included headache, neurological deficits, aneurysmal subarachnoid hemorrhage, incidental or asymptomatic aneurysm, and traumatic subarachnoid hemorrhage. Twenty-five cases of intracranial aneurysms in 25 patients were identified. The aneurysms were saccular (32%, 8/25), dissecting (52%, 13/25), and fusiform (16%, 4/25) in shape. Treatment modalities included direct clipping, embolization, bypass, trapping, resection, coarctation of internal carotid artery (ICA), and endovascular vessel sacrifice. Of the 25 aneurysms, 16 (64%, 16/25) aneurysms were located in anterior circulation, and 9 (36%, 9/25) were located in the posterior circulation, while multiple aneurysms were identified in two patients. A preoperative magnetic resonance perfusion (MRP) examination was performed in 15 patients with unruptured complex aneurysms, of whom 13/15 (86.67%) showed hypoperfusion. Eighteen (78.26%, 18/23) patients had no postoperative complications, temporary complications occurred in 4 (17.39%, 4/23) patients, and 1 patient died postoperatively. The intracranial aneurysms in young adults (15 ~ 24 years old) are rare. The posterior circulation is more commonly involved than adults, giant and huge aneurysms are frequent, and fusiform and dissecting pathologic features are common. Headache is the most common clinical manifestation. Individualized treatment should be performed, and bypass is an effective treatment for young patients with intracranial aneurysms.

Flat Detector CT with Cerebral Pooled Blood Volume Perfusion in the Angiography Suite: From Diagnostics to Treatment Monitoring

C-arm flat-panel detector computed tomographic (CT) imaging in the angiography suite increasingly plays an important part during interventional neuroradiological procedures. In addition to conventional angiographic imaging of blood vessels, flat detector CT (FD CT) imaging allows simultaneous 3D visualization of parenchymal and vascular structures of the brain. Next to imaging of anatomical structures, it is also possible to perform FD CT perfusion imaging of the brain by means of cerebral blood volume (CBV) or pooled blood volume (PBV) mapping during steady state contrast administration. This enables more adequate decision making during interventional neuroradiological procedures, based on real-time insights into brain perfusion on the spot, obviating time consuming and often difficult transportation of the (anesthetized) patient to conventional cross-sectional imaging modalities. In this paper we review the literature about the nature of FD CT PBV mapping in patients and demonstrate its current use for diagnosis and treatment monitoring in interventional neuroradiology.

Endovascular treatment of type 1 and type 4 non-saccular aneurysms of cerebral arteries - a single-Centre experience

AIM OF THE STUDY

The aim of this study was to evaluate our results regarding treatment options, complications, and outcomes in patients with non-saccular aneurysms of cerebral arteries belonging to type 1 and type 4 according to Mizutani's classification.

METHODS

A total of 26 aneurysms in 26 patients were treated between 2014 and 2019. There were 13 males (mean age 42.77 ± 11.73 years) and 13 females (mean age 50.84 ± 9.37 years). In 23 cases the onset was haemorrhagic and in three cases non-haemorrhagic. A combination of conventional stents and coils was used in 10 cases, conventional stents and flow diverters in three cases, flow diverters and coils in five cases, and flow diverters only were used in eight cases. Radiological results of treatment were assessed after eight months and clinical after one year.

RESULTS

In 24 patients, aneurysms were occluded at the end of the follow-up period. An iatrogenic dissection and two haemorrhagic complications were registered. In three cases, parent arteries were occluded due to re-growth of the aneurysm, which caused middle cerebral artery infarction in one case. A favourable clinical outcome was registered in 19, patients, and non-favourable in five. Two patients died in the early postoperative period due to extensive damage to the brain parenchyma caused by initial bleeding.

CONCLUSION

Our results indicate that treatment of type 1 and type 4 non-saccular aneurysms with various combination of stents and flow diverters, with or without coils, is promising, although very challenging and technically demanding.

Reconstructive vs Deconstructive Endovascular Approach to Intradural Vertebral Artery Aneurysms: A Multicenter Cohort Study

BACKGROUND

Parent vessel sacrifice (PVS) has been a traditional way of treating complex aneurysms of the intradural vertebral artery (VA). Flow diversion (FD) has emerged as an alternative reconstructive option.

OBJECTIVE

To compare the long-term clinical and radiographic outcomes of intradural VA aneurysms following PVS or FD.

METHODS

We retrospectively reviewed and evaluated 43 consecutive patients between 2009 and 2018 with ruptured and unruptured intradural VA aneurysms treated by PVS or FD. Medical records including clinical and radiological details were reviewed.

RESULTS

A total of 43 intradural VA aneurysms were treated during this period. In the 14 PVS patients, the mean follow-up was 19.5 mo, and 71.4% of cases achieved modified Rankin scale (mRS) ≤2 at the last follow-up. A total of 86.5% of cases achieved complete occlusion. There was a 14.3% (2 cases) mortality rate, 14.3% (2 cases) postoperative ischemic complication rate, and 0% postoperative hemorrhaging rate. Retreatment was required in 1 case (7.1%). In the 29 FD patients, the mean follow-up was 21.8 mo, and 89.7% of cases achieved mRS ≤2 at the final follow-up. There was a 3.2% (1 case) mortality rate, 19.4% (6 cases) of postoperative ischemic complications, and 6.5% (2 cases) of postoperative hemorrhagic complications. Complete occlusion was seen in 86.5% patients. No cases required retreatment. Mortality and complication rates were not significantly different between PVS and PED (Pipeline Embolization Device) groups.

CONCLUSION

PVS was associated with comparable intraprocedural complications for VA aneurysms as compared to FD in the largest multicenter study to date. Both procedures have good long-term clinical and radiological outcomes.

Pipeline embolization of posterior circulation aneurysms: a multicenter study of 131 aneurysms

OBJECTIVE

Flow diversion for posterior circulation aneurysms performed using the Pipeline embolization device (PED) constitutes an increasingly common off-label use for otherwise untreatable aneurysms. The safety and efficacy of this treatment modality has not been assessed in a multicenter study.

METHODS

A retrospective review of prospectively maintained databases at 8 academic institutions was performed for the years 2009 to 2016 to identify patients with posterior circulation aneurysms treated with PED placement.

RESULTS

A total of 129 consecutive patients underwent 129 procedures to treat 131 aneurysms; 29 dissecting, 53 fusiform, and 49 saccular lesions were included. At a median follow-up of 11 months, complete and near-complete occlusion was recorded in 78.1%. Dissecting aneurysms had the highest occlusion rate and fusiform the lowest. Major complications were most frequent in fusiform aneurysms, whereas minor complications occurred most commonly in saccular aneurysms. In patients with saccular aneurysms, clopidogrel responders had a lower complication rate than did clopidogrel nonresponders. The majority of dissecting aneurysms were treated in the immediate or acute phase following subarachnoid hemorrhage, a circumstance that contributed to the highest mortality rate in those aneurysms.

CONCLUSIONS

In the largest series to date, fusiform aneurysms were found to have the lowest occlusion rate and the highest frequency of major complications. Dissecting aneurysms, frequently treated in the setting of subarachnoid hemorrhage, occluded most often and had a low complication rate. Saccular aneurysms were associated with predominantly minor complications, particularly in clopidogrel nonresponders.

Pediatric Intracranial Aneurysms: Favorable Outcomes Despite Rareness and Complexity

OBJECTIVE

Pediatric intracranial aneurysms (IAs) are rare and differ from their adult counterparts in terms of their aneurysmal characteristics, presentation, treatment, and outcomes. Their treatment is often more difficult and complex compared with that of adults. However, studies outlining the clinical effect of pediatric IAs remain sparse.

METHODS

We retrospectively reviewed the data from patients aged ≤18 years admitted to our hospital from 2000 to 2017 with a diagnosis of IAs.

RESULTS

From the sample of 8207 patients with an IA diagnosis, 26 patients with 33 IAs were involved. Our cohort included 17 males and 9 females, with a mean age of 12.5 years. The mean follow-up duration was 4 years and 3 months. Seven patients (26.92%) were assumed to have a traumatic origin for their IAs. Ruptured aneurysms were more common than unruptured ones (61.53% vs. 38.46%). Complex features were observed in 14 aneurysms (42.42%). Initially, microsurgical and endovascular treatment were both performed in 10 patients (38.46%). A good recovery was obtained in 16 patients (61.54%) as determined by the Glasgow outcome scale scores at the 6-month follow-up visits. The complete obliteration of aneurysms was observed in 17 patients (65.38%). Endovascular treatment was the initial treatment in 3 patients with incomplete obliteration.

CONCLUSIONS

The treatment of pediatric IAs is challenging and technically demanding owing to their discrete nature compared with adult IAs and the need for greater surgical skills. We found a male predominance, with internal carotid artery bifurcation as the most frequent location of the aneurysms. Despite the greater incidence of ruptured and complex aneurysm cases, many patients had experienced a good recovery at the 6-month follow-up examinations.

Comparison of Safety and Effectiveness of Endovascular Treatments for Unruptured Intracranial Large or Giant Aneurysms in Internal Carotid Artery

PURPOSE

To analyze and compare safety and efficacy of different endovascular treatment modalities for unruptured intracranial large or giant aneurysms.

METHODS

We retrospectively reviewed 126 consecutive patients with 128 large (15-24 mm) or giant (≥25 mm) aneurysms that were treated with different endovascular procedures between January 2014 and February 2017. We compared clinical and angiographic outcomes and occurrence of technical events among 3 treatment modalities.

RESULTS

Complete occlusion at last follow-up was achieved in 65.6%, 90.5%, and 72.0% of aneurysms in stent-assisted coiling, parent artery occlusion, and Pipeline embolization device (PED) groups (P = 0.119). Complete occlusion rate at 6-month follow-up (odds ratio = 1.81, P = 0.396) and at last angiographic follow-up (odds ratio = 3.64, P = 0.123), was not superior with parent artery occlusion compared with PED. Retreatment rate was significantly different among all groups (P < 0.001); the rate was highest in the stent-assisted coiling group (21.9%). Rates of hemorrhagic events and ischemic events were not significantly different among groups (P = 0.581). Mass effect exacerbation was more frequently seen in the stent-assisted coiling group (24.4% vs. 7.7% and 3.3%, P = 0.004). Major complication rate was higher in the parent artery occlusion group compared with the PED group, but the difference was not statistically significant (19.2% vs. 16.4%, odds ratio = 1.21, P = 0.763). Rate of technical events was significantly different in the 3 groups (P = 0.0437), and technical events occurred more often in the PED group (18.0%).

CONCLUSIONS

For large and giant aneurysms located in the internal carotid artery, outcome for endovascular treatment remains poor, even with the introduction of PED.

Intraoperative Test Occlusion as Adjustment of Extracranial-to-Intracranial Bypass Strategy for Unclippable Giant Aneurysm of the Internal Carotid Artery

BACKGROUND

There is still a controversy for low-flow extracranial-intracranial or high-flow extracranial-intracranial bypass with proximal occlusion in the treatment of unclippable giant internal carotid artery aneurysms.

CASE DESCRIPTION

A 61-year-old woman presented with a 1-month history of double vision. Neuroimages revealed an unclippable giant internal carotid artery aneurysm located from the cavernous sinus to proximal site of the posterior communicating artery. Ipsilateral A1 of the anterior cerebral artery was hypoplastic, and posterior communicating artery was patent. Intraoperative proximal test occlusion at cervical internal carotid artery under neurophysiological monitoring, instead of preoperative balloon test occlusion, was performed to assess whether low-flow bypass was sufficient. The monitoring was unchanged during test occlusion, and the aneurysm was successfully trapped without high-flow bypass. Neither ischemic lesion nor neurologic deficits were found postoperatively.

CONCLUSIONS

Intraoperative proximal test occlusion is useful to decide on the surgical procedure of revascularization in patients with unclippable internal carotid aneurysm.

The active participation of p22phox-214T/C in the formation of intracranial aneurysm and the suppressive potential of edaravone

Oxidative stress reactions play an important role in the pathogenesis of intracranial aneurysm (IA). p22phox is involved in the oxidative stress reaction, and it is a critical subunit of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. The present study investigated the association of genetic variants within the gene encoding p22phox‑214T/C with IA. The p22phox‑214T/C gene polymorphisms in 192 cases of IA and 112 controls were analyzed by polymerase chain reaction‑restriction fragment length polymorphism (PCR‑RFLP). The mRNA expression of NADPH oxidase was also analyzed by RT‑PCR. The results of RT‑PCR were validated by ELISA. In a rabbit model of elastase‑induced aneurysm, we used edaravone for anti‑oxidative stress treatment to observe the curative effects. In the clinical cases, a significant difference in p22phox‑214T/C allele frequencies in the IA group was observed compared with the control group (P<0.001). The expression level of NADPH oxidase was differed significantly between the IA group and the control group. In the rabbit model of elastase‑induced aneurysm, the success rate of the aneurysmal model in the edaravone group and the wound ulcer rate were lower than those in the control group. In addition, the diameter of the aneurysm was smaller than in the edaravone group than in the control group (3.26±0.13 mm vs. 3.85±0.07 mm), and the expression of matrix metalloproteinase‑9 (MMP‑9) was significantly lower than that in the control group (P<0.0001). Thus, these data suggest the active participation of p22phox‑214T/C in the formation of IA and the suppressive potential of edaravone against IA formation.