Microsurgical clipping and endovascular flow diversion of ruptured anterior circulation blood blister-like aneurysms

Multimodal Management of Ruptured Internal Carotid Artery Blood Blister-like Aneurysm: Technical Notes and Case Series of Surgical Muscle Wrapping and Fenestration Clipping Combined with Flow-Diverter Embolization

OBJECTIVE

To evaluate the effects of a multimodal management technique combining surgical muscle wrapping, clipping, and flow-diverter stent (FDS) placement in patients with ruptured blood blister-like aneurysms (BBAs) in the internal carotid artery (ICA).

METHODS

In a retrospective case series review from 2020 to 2023, 3 patients with ruptured ICA BBAs underwent multimodal management, an approach combining muscle wrapping, surgical clipping, and FDS embolization. The aneurysm sac was initially packed and wrapped with multiple tailored temporalis muscle grafts and then secured using fenestration clips, with good preservation of the ICA branches. The FDS was placed 2-3 weeks after the clipping.

RESULTS

All 3 patients had right ICA BBAs (mean age, 52 years). The modified Hunt and Hess grades ranged from 2 to 3, and the Fisher grades ranged from 3 to 4. The mean angiography follow-up time was 27.7 months (15, 31, and 37 months). There were no instances of symptomatic vasospasm or visible ischemic stroke during follow-up computed tomography. No patient required cerebrospinal fluid shunt implantation, and all achieved favorable neurological outcomes (modified Rankin scale 0-1). Follow-up digital subtraction angiography revealed no evidence of aneurysm recurrence or significant ICA stenosis.

CONCLUSIONS

We discuss a promising multimodal management approach for ruptured ICA BBAs combining muscle wrapping, surgical clipping, and FDS embolization. This technique was safe and effective in preventing re-rupture, achieving positive short-term clinical outcomes. Further research and more extensive studies are required to validate the long-term efficacy of this approach.

Flow diverting stent monotherapy as the best choice in the treatment of intracranial blood blister-like aneurysms: a systematic review

OBJECTIVE

To evaluate the effectiveness and safety of flow-diverting stent (FDS) monotherapy in the treatment of intracranial blood blister-like aneurysms (BBAs) through a detailed systematic review.

METHODS

This review adheres to the PRISMA guidelines, focusing on studies utilizing FDS monotherapy for BBAs, spanning from July 2010 to November 2023. A systematic search across databases including Embase, Medline/PubMed, Scopus, and Google Scholar was conducted. Studies in English that solely used FDS for BBA treatment and assessed perioperative complications were included. Data from 23 studies encompassing 181 cases were systematically analyzed for patient demographics, aneurysm characteristics, treatment specifics, and outcomes.

RESULTS

The collected data indicates a dominant occurrence of BBAs in the internal carotid artery (86.9%), with a mean patient age of 50.27 years and a higher prevalence in females (73.43%). Treatment timing varied, with 45.9% treated within the first three days, 35.7% were treated between 4 and 14 days, and 18.4% of patients were treated after 14 days. The study found a complete occlusion rate of 88.1% in follow-up imaging and a favorable clinical outcome in 82.2% of cases. Periprocedural complications were reported in 19.2% of patients, with a related mortality rate of 3.9%.

CONCLUSIONS

The systematic review demonstrates that FDS monotherapy is highly effective and safe in the treatment of intracranial BBAs. It offers a high rate of complete aneurysm occlusion, favorable clinical outcomes, and low complication rates. These results highlight FDS monotherapy as a prominent treatment method, ensuring robust aneurysmal protection while maintaining the patency of the parent artery.

Interventions to treat patients with blood blister-like aneurysms of the internal carotid artery: a protocol for a network meta-analysis

INTRODUCTION

Blood blister-like aneurysm (BBA) is a special type of intracranial aneurysm with relatively low morbidity and high mortality. Various microsurgical techniques and endovascular approaches have been reported, but the optimal management remains controversial. For a better understanding of the treatment of BBA patients, a network meta-analysis that comprehensively compares the effects of different therapies is necessary.

METHODS AND ANALYSIS

This protocol has been reported following the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. Related studies in the following databases will be searched until November 2022: PubMed, Embase, Scopus, Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI), VIP and Wanfang. Randomised controlled trials (RCTs) and non-randomised studies comparing at least two different interventions in BBA patients will be included. Quality assessment will be conducted using Cochrane Collaboration's tool or Newcastle-Ottawa Scale based on their study designs. The primary outcome is the composite of the incidences of intraoperative bleeding, postoperative bleeding and postoperative recurrence. The secondary outcome is an unfavourable functional outcome. Pairwise and network meta-analyses will be conducted using STATA V.14 (StataCorp, College Station, Texas, USA). Mean ranks and the surface under the cumulative ranking curve will be used to evaluate every intervention. Statistical inconsistency assessment, subgroup analysis, sensitivity analysis and publication bias assessment will be performed.

ETHICS AND DISSEMINATION

Ethics approval is not necessary because this study will be based on publications. The results of this study will be published in a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42022383699.

Endovascular intervention vs. microsurgery on the prognosis of anterior circulation blood blister-like aneurysm: A cohort study

Background

There are no universally acknowledged standardized treatment strategies for blood blister-like aneurysms (BBAs). This study compared the prognosis of patients with BBA who underwent craniotomy microsurgery vs. endovascular intervention.

Methods

This retrospective cohort study included patients with BBA treated between September 2009 and August 2020 at Sichuan Provincial People's Hospital affiliated to the Sichuan Academy of Medical Science. Patients were divided into the microsurgery and endovascular groups. The preoperative Hunt-Hess grade and modified Fisher grade were collected. The intraoperative and postoperative complications (including intraoperative aneurysm rupture and hemorrhage, postoperative cerebral hemorrhage, and BBA recurrence) were recorded.

Results

Seventy-two patients were included: 28 and 44 in the microsurgery and endovascular groups, respectively. Only the preoperative Fisher grade was different between the two groups (P = 0.041). The proportion of patients with good outcomes was lower in the microsurgery group (28.6%) than in the endovascular group (72.7%), and the mortality rate was higher in the microsurgery group (32.1%) than in the endovascular group (11.4%) (P < 0.05). After adjustment for the modified Fisher grade, the multivariable analysis showed that compared with craniotomy microsurgery, an endovascular intervention was associated with the prognosis of patients with BBA (OR = 0.128, 95%CI: 0.040-0.415, P < 0.001). The rate of complications (intraoperative hemorrhage, cerebral infarction, and recurrence) was higher in the microsurgery group than in the endovascular group.

Conclusion

In patients with BBA, an endovascular intervention appears to be associated with a better prognosis compared with craniotomy microsurgery.

Endovascular treatment of a ruptured blister-like aneurysm at an azygos anterior cerebral artery: A case report and review of the literature

Background

Endovascular treatment for a ruptured blister-like aneurysm (BLA) has recently become a hopeful approach. BLAs are usually located on the dorsal wall of the internal carotid artery, whereas one located on the azygos anterior cerebral artery (ACA) is so rare, it has never been reported. We report a case of a ruptured BLA arising at the distal bifurcation of an azygos ACA treated by stent-assisted coil embolization.

Case Description

A 73-year-old woman presented with a disturbance of consciousness. Computed tomography showed diffuse subarachnoid hemorrhage, which was observed to be particularly dense in the interhemispheric fissure. Three-dimensional rotation angiography showed a tiny and conical bulge on the distal bifurcation of the azygos trunk. Follow-up digital subtraction angiography performed on day 4 showed enlargement of the aneurysm, and a BLA arising at the azygos bifurcation was diagnosed. Stent-assisted coiling (SAC) was performed using a low-profile visualized intraluminal support (LVIS) Jr. stent, which was implanted from the left pericallosal artery to the azygos trunk. Follow-up angiography showed that the aneurysm thrombosed gradually and reached complete occlusion 90 days after onset.

Conclusion

SAC for a BLA at the distal bifurcation of an azygos ACA might be an effective treatment option leading to early complete occlusion, but thrombus formation as an intraoperative complication should be noted in the BLA at the bifurcation or the peripheral artery, as in the present case.

Early Treatment of Ruptured Blood Blister-Like Aneurysms of the Internal Carotid Artery With Flow Diverters Using Single Antiplatelet Therapy: A Single-Center Experience With Long-Term Follow-Up

Background and Purpose: Blood Blister-like aneurysms (BBAs) of the internal carotid artery (ICA) are rare entities of cerebral aneurysms. FD use in acutely ruptured aneurysms, timing of treatment and antiplatelet regimen are main debate topics in clinical practice when the treatment decision is flow diversion. The aim of this study is to report the safety and efficacy of a single-center FD treatment for ruptured BBAs in the early phase of SAH using the SAPT regimen.

Material and Method: This study involved a retrospective analysis of a prospectively collected database. Records of patients admitted to our clinic and treated by endovascular route on ruptured BBA between January 2013 and December 2020 were reviewed. Ruptured supraclinoid ICA BBAs treated with FD devices with SAPT within 48 h from ictus of SAH are included. BBA of atypical anatomic locations, other endovascular techniques performed, and delayed admissions (>48 h) were excluded from the study. Demographic, clinical and angiographic features of patients and aneurysms, FD types and numbers, periprocedural complications, immediate and follow-up angiographic and clinical outcomes were recorded.

Results: A total of six patients with ruptured BBAs treated via FDs within 48 h and used SAPT were included in the study. The mean age was 41.6 years (range from 34 to 45 years), and four of six patients were female. All patients were treated within 48 h after ictus, and the mean treatment day was 1.33 days. One patient received ticagrelor, and five patients received prasugrel as SAPT for one year after treatment. No procedure-related death and rebleeding were recorded. One (16.7 %) treatment responsive procedure-related complication occurred (transient ischemia). Overall good outcome rate was 83.3%. One patient died due to pneumonia. The immediate control angiograms showed complete occlusions of BBAs in one patient (16.6%). The complete occlusion rate was 100 % for five survivors at the control angiogram. The median follow-up was 49.5 months.

Conclusion: This single-center experience suggests that early treatment (<2 days) within SAH of ruptured BBAs with FDs using SAPT is safe and effective in terms of clinical and radiological long-term outcomes.

Slip Clip after successful microsurgery of a blister aneurysm: Should bypass always be the first option?

Blood Blister-like aneurysms are intracranial non-saccular aneurysms with higher rupture risk due to its fragile wall. Diagnosis is performed in the acute phase of a subarachnoid hemorrhage. There are several treatment options based on reconstructive or deconstructive techniques. This paper aims to discuss the limitations of microsurgery clipping for a ruptured blister aneurysm. We report on a case of a female patient presented with a Fisher III subarachnoid hemorrhage. Cerebral angiography revealed an internal carotid artery blister aneurysm. Initially microsurgery clipping was successfully performed. However, after a few days the patient presented new subarachnoid hemorrhage. The new cerebral angiography showed growth of the previously clipped aneurysm, with displacement of the clip from the position adjacent to the artery. High-flow bypass was performed obtaining definitive treatment. This is a definitive approach for blister aneurysms. If microsurgery clipping is chosen, a strict follow-up is required due to the dynamic nature of this lesion and the chance of re-bleeding even after successfully clipping.

Endovascular Treatment of Posterior Circulation Saccular Aneurysms With the p64 Flow Modulation Device: Mid-and Long-Term Results in 54 Aneurysms From a Single Center

Objective: Flow diverter (FD) stents have become one of the most common tools for treating intracranial aneurysms; however, their role in treating posterior circulation aneurysms is still discussed with controversy. In this study, we evaluated the safety and effectiveness of p64 FD for the treatment of saccular, unruptured aneurysms in the posterior circulation over a long-term follow-up period in a single center. Methods: From our prospectively maintained database, we retrospectively identified patients who underwent treatment of an intracranial saccular aneurysm arising from the posterior circulation with ≥1 p64 FD implanted or attempted between October 2012 and December 2019. Aneurysms could have been treated with prior or concomitant saccular treatment (e.g., coiling, intra-aneurysmal flow diversion). Aneurysms with parent vessel implants other than p64, fusiform aneurysms, and dissections were excluded. Peri- and postprocedural complications, clinical outcome, and clinical and angiographic follow-up results were evaluated. Results: In total, 54 patients (45 female, 9 male; mean age 55.1 years) with 54 intracranial aneurysms met the inclusion criteria. In 51 cases (94.4%), one p64 was implanted; in 2 cases (3.7 %), two p64s were implanted; in one case, deployment of the p64 was not feasible. Procedural complications occurred in 3.7% and postprocedural complications in 9.3 %, respectively. Hemorrhagic complications occurred in 2/54 patients (3.7%), thereof one fatal parenchymal hemorrhage. Ischemic complications were observed in 5/54 patients (9.3%). Early, mid-term, and long-term angiographic follow-up examinations showed complete or near-complete aneurysm occlusion, defined according to the O'Kelly -Marotta (OKM) scale as OKM C + D in 56, 75.6, and 82.9 %, respectively. Asymptomatic side vessel occlusions occurred in 3.8%, each during the first follow-up. Conclusions: The implantation of a p64 FD is a safe and effective device for endovascular treatment of posterior circulation saccular aneurysms with a high success rate and low morbi-mortality.

Comparison of Blister Aneurysm Treatment Techniques: A Systematic Review and Meta-Analysis

OBJECTIVE

Blood blister aneurysms are small, thin-walled, rapidly growing side-wall aneurysms that have proved particularly difficult to treat, and evidence-based guidance for treatment strategies is lacking. A systematic review and meta-analysis was performed to aggregate the available data and compare the 3 primary treatment modalities.

METHODS

We performed a comprehensive literature search according to PRISMA guidelines followed by an indirect meta-analysis that compares the safety and efficacy of surgical, flow-diverting stents (FDS), and other endovascular approaches for the treatment of ruptured blood blister aneurysms.

RESULTS

A total of 102 studies were included for quantitative synthesis, with sample sizes of 687 treated surgically, 704 treated endovascularly without FDS, and 125 treated via flow diversion. Comparatively, FDS achieved significantly reduced rates of perioperative retreatment compared with both surgical (P = 0.025) and non-FDS endovascular (P < 0.001). The FDS subgroup also achieved a significantly lower incidence of perioperative rebleed (P < 0.001), perioperative hydrocephalus (P = 0.012), postoperative infarction (P = 0.002), postoperative hydrocephalus (P < 0.001), and postoperative vasospasm (P = 0.002) compared with those patients in the open surgical subgroup. Although no significant differences were found among groups on the basis of functional outcomes, angiographic outcomes detailed by rates of radiographic complete occlusion were highest for surgical (90.7%, 262/289) and FDS (89.1%, 98/110) subgroups versus the non-FDS endovascular subgroup (82.7%, 268/324).

CONCLUSIONS

Flow diversion seems to be an effective treatment strategy for ruptured blood blister aneurysms, with lower rates of perioperative complications compared with surgical and other endovascular techniques, but studies investigating long-term outcomes after flow diversion warrant further study.

Safety and Efficacy of Endovascular Therapy for Blood Blister-Like Aneurysms: Willis Covered Stents and Double Stents Assistant Coils-A Single Center Cohort Study

Objective: To summarize and discuss the application of Willis covered stents (WCSs) and double stent-assisted coils in the treatment of blood blister-like aneurysms (BBAs).

Materials and Methods: Thirty-two patients with BBAs treated from January 2015 to October 2020 were included in the study. Among them, 18 were treated using WCSs and 14 using double stents-assisted coils. The indications for treatment, perioperative findings, and postoperative follow-up results were collected and analyzed.

Results: All 32 patients had successful stent deployments. Complete aneurysm occlusion was achieved in all 18 patients treated with WCSs immediately. WCS-related adverse events included 2 cases of mild vasospasm and 4 aggressive procedure-related vasospasms during WCS deployment, a case of dissection after WCS deployment, and 1 death due to ipsilateral temporal lobe rebleeding at the sixth day after WCS deployment. In patients treated with double stent-assisted coils, there were 3 cases of neck remnants, 1 acute occlusion of the ipsilateral MCA branch, and 4 mild procedure-related intraoperative vasospasms. The mean follow-up period was 4.2±1.6 months (range 3–6 months). Follow-up imaging data were available for 25 patients (78.1%). In the first postoperative angiographic follow-up, all BBAs were completely occluded. Mild asymptomatic stent stenosis was observed in 3 patients treated with WCSs. Follow-up examination at 6 months after the employment of WCSs showed that the modified Rankin score (mRs) was 0 in 6 patients, 1 in 5 patients, 2 in 3 patients, 3 in 1 patient, 4 in 2 patients, and 6 in 1 patient. After treatment with double stents-assisted coils, the mRs was 0 in 4 patients, 1 in 5 patients, 2 in 3 patients, and 4 in 2 patients.

Conclusions: WCSs and double stent-assisted coils for the treatment of BBAs are both safe and efficient. WCSs provide a higher rate of immediate occlusion; however, there was no significant difference in the long term.

Aneurysm Treatment in Acute SAH with Hydrophilic-Coated Flow Diverters under Single-Antiplatelet Therapy: A 3-Center Experience

BACKGROUND AND PURPOSE

In certain clinical circumstances, dual-antiplatelet therapy can be problematic in patients with acute SAH. In some aneurysms, however, flow-diverting stents are the ideal therapeutic option. We report our experience with ruptured intracranial aneurysms treated with flow diverters with hydrophilic coating (p48 MW HPC and p64 MW HPC) under single-antiplatelet therapy.

MATERIALS AND METHODS

Patients were treated with either flow-diverter placement alone or a flow diverter and additional coiling. Due to the severity of the hemorrhage, the potential for periprocedural rehemorrhage, and the potential for additional surgical interventions, a single-antiplatelet regimen was used in all patients.

RESULTS

Thirteen aneurysms were treated in 10 patients. The median age was 62 years; 5 patients were male. All had acute SAH due to aneurysm rupture. Four blood-blister, 2 dissecting, and 7 berrylike aneurysms were treated. Seven aneurysms were adjunctively coiled. Eight of the 10 patients received a single-antiplatelet protocol of aspirin, 1 patient was treated with prasugrel only, and 1 patient was treated with tirofiban first and then switched to the aspirin single-antiplatelet protocol. One device-related complication occurred, a thrombosis of an overstented branch. All stents, however, remained open at DSA, CTA, or MRA follow-up.

CONCLUSIONS

The implantation of flow diverters with reduced thrombogenicity due to hydrophilic surface coating under single-antiplatelet therapy seems to be an option in carefully selected cases of SAH due to aneurysm rupture.

Endovascular Treatment of Ruptured Intracranial Blister Aneurysms: A Systematic Review and Meta-analysis

BACKGROUND

Endovascular treatment of blister aneurysms is a promising approach, even though they are vascular lesions challenging to treat due to their angioarchitectural characteristics.

PURPOSE

Our aim was to investigate clinical and radiologic outcomes after endovascular treatment of ruptured blister aneurysms.

DATA SOURCES

PubMed, Ovid MEDLINE, Ovid EMBASE, Scopus, and the Web of Science were screened.

STUDY SELECTION

We performed a comprehensive review of the literature from 2010 to 2019 reporting series of patients with blister aneurysms treated with an endovascular approach.

DATA ANALYSIS

Event rates were pooled across studies using a random effects meta-analysis.

DATA SYNTHESIS

A total of 32 studies reporting on 684 patients (707 aneurysms) were included. Stent placement, stent-assisted coiling, and flow diversion were the most commonly described treatments (282, 256, and 155 patients, respectively). The long-term complete occlusion rate was 76.9% (95% CI, 69.2%-83.9%). The perioperative complication rate was 8.9%, and clinical outcome at final follow-up was mRS <2 in 76.6% (95% CI, 68.2%-84.2%) of patients. The mortality rate was 4.7% (95% CI, 2.30%-7.80%). Among the different techniques, stent-assisted coiling is the one that had the higher rate of immediate occlusion (63.4%); however, the occlusion rate at the final follow-up was comparable among the different techniques.

LIMITATIONS

Different techniques were described and data were reported in a nonhomogeneous way, possibly representing a bias in the present study.

CONCLUSIONS

This study suggests that endovascular treatment of blister aneurysms is associated with good long-term occlusion rates and reasonable complication and mortality rates. There is no consensus on the best endovascular techniques in blister aneurysm management.

Thrombogenicity of the p48 and anti-thrombogenic p48 hydrophilic polymer coating low-profile flow diverters in an in vitro human thrombin generation model

OBJECTIVES

The implantation of flow diverters, or stents in general, necessitates the use of dual anti-platelet treatment with typical regimes including aspirin and a P2Y12 inhibitor. This carries an inherent risk of haemorrhage. We sought to compare the thrombogenicity of the anti-thrombogenic p48 hydrophilic polymer coating compared to the standard uncoated p48 flow diverter using an in vitro thrombogenicity assay.

METHODS

To evaluate the thrombin generation influenced by the different stent types the stents were placed in wells of a 24-well plate with the addition of plasma from healthy volunteers the thrombin calibrator respectively the PPP-reagent was added. Subsequently, the thrombin substrate was added and the thrombin generation was analysed every 60 s using a thrombinoscope. The assay is calibrated using samples containing a known amount of active thrombin in PPP. Thrombin activity is proportional to the change in fluorescence.

RESULTS

The p48 hydrophilic polymer coating shows a significantly lower peak thrombin concentration (1.13 ± 0.21 vs. 1.41 ± 0.22) and longer time to peak thrombin concentration (0.96 ± 0.04 vs. 0.74 ± 0.07) compared to the uncoated p48 device (p < 0.01). The responses of the p48 hydrophilic polymer coating were similar to that of the negative control.

CONCLUSION

The hydrophilic polymer coating surface modification significantly reduces the thrombogenicity of the p48 flow diverter. These results corroborate the findings from previous in vitro studies.