Blood blister-like aneurysms: Single center experience and systematic literature review

Treatment of Acute Iatrogenic Cerebrovascular Injury Using Flow Diverter Stents

BACKGROUND AND OBJECTIVES

Iatrogenic cerebrovascular injury can cause intracranial hemorrhage and pseudoaneurysm formation, putting patients at high risk for postoperative bleeding. No consensus for management exists. This study describes endovascular treatment of these acute injuries with flow diverter stents.

METHODS

Electronic medical records were retrospectively reviewed for injury type and etiology, timing of diagnosis, and endovascular management, including antiplatelet regimens, embolization results, and clinical outcome.

RESULTS

Six patients were included. Three suffered an injury to the internal carotid artery, 1 suffered an injury to the left anterior cerebral artery, 1 suffered an injury to the right posterior cerebral artery, and 1 suffered an injury to the basilar artery. Four of the 6 injuries occurred during attempted tumor resection, 1 occurred during cerebrospinal fluid leak repair, and 1 occurred during an ophthalmic artery aneurysm clipping. All injuries resulted in pseudoaneurysm formation. Four were immediately detected on angiography; 2 were initially negative on imaging. Five were treated with a pipeline embolization device, and 1 was treated with a Silk Vista Baby. Two were treated with 2 pipeline embolization devices telescopically overlapped across the pseudoaneurysm. All devices deployed successfully. No pseudoaneurysm recurrence or rebleeding occurred. No parent artery occlusion or stenosis was observed, and complete pseudoaneurysm occlusion was observed in 4 patients (in 2 patients, follow-up imaging could not be obtained).

CONCLUSION

With proper antiplatelet regimens, flow diverter stents can be used safely to successfully treat complex acute iatrogenic injuries. Early repeat angiogram is needed when immediate postinjury imaging does not discover the point of vessel injury.

Congenital and acquired anomalies of the basilar artery: A pictorial essay

INTRODUCTION

The basilar artery is one of the two cases in our body where an arterial vessel is formed by the union of two others - the vertebral arteries. It provides vascular supply to essential structures for the main vital functions; the posterior cerebral arteries originate from it as terminal branches, and form part of the anastomotic circle of Willis.

IMAGING FINDINGS

Congenital and acquired anomalies of the basilar trunk are described. We provide a schematic and detailed representation of normal anatomical variants - mainly represented by the fenestrated basilar artery or the persistence of carotid-basilar anastomosis; course anomalies are also illustrated, with reference to neuro-vascular conflicts and dolichoectasia. Among congenital anomalies, this pictorial review also shows the variants of the basilar origin, such as in the case of basilar trunk arising from only one of the two vertebral arteries, and the calibre changes - which are represented by aneurysm and hypoplasia. The latter appears to be a risk factor for posterior circulation stroke, when associated with a bilateral posterior foetal variant.Among the acquired forms, this pictorial essay describes some clinical cases of dissections, non-congenital aneurysms, thrombosis and tumour with vascular encasing or compression of basilar artery.

CONCLUSION

CT angiography and MRI allow us to study the posterior intracranial circulation in detail, providing useful pre-treatment information. Therefore, knowledge of congenital or acquired anomalies of the basilar artery is essential for radiologists, neuroradiologists and neurosurgeons.

Persistent hydrocephalus following posterior fossa tuberculoma removal in pediatrics: A case report from a referral center in Indonesia

INTRODUCTION

The threat posed by tuberculosis persists in developing countries. Individuals under the age of five were more likely to develop central nervous system (CNS) tuberculosis. CNS Tuberculoma of the posterior fossa has rarely been reported, and its consequences are more devastating due to the limited space of the posterior fossa.

CASE PRESENTATION

A 4-year old male was referred to our academic general hospital with main complaint of decreased consciousness for the last 3 days. The patient has experienced a low-grade fever, cough, and an enlarging neck tumor for two months. Any contact with confirmed tuberculosis patients was denied by the family. A suspected cerebellar abscess and obstructive hydrocephalus led to the patient's referral. Urgent evacuation of the posterior fossa mass was conducted, revealing a histopathological diagnosis of tuberculoma. After the procedure, the patient experienced seizures and no improvement of GCS. A head CT scan evaluation revealed a communicating hydrocephalus. A ventriculoperitoneal shunt is done, resulting in improvement of the patient's consciousness after CSF diversion.

DISCUSSION

The haematogenous spread of Mycobacterium, which causes granulomatous foci in the brain, is the cause of CNS tuberculoma. The neuroradiological characteristic of tuberculomas may mimic several conditions. Thorough history-taking and physical examination may lead to a focused differential diagnosis of the patient. Evacuated posterior fossa tuberculoma usually leads to resolved obstructing hydrocephalus. A persistent hydrocephalus leads to the possibility of communicating hydrocephalus due to tuberculous meningoencephalitis. Close monitoring following excision of posterior fossa tuberculoma may help identify persistent hydrocephalus early on.

CONCLUSION

CNS tuberculoma should remain a differential diagnosis of ring-enhancing posterior fossa mass, especially in pediatrics. This condition may present concomitantly with tuberculous meningoencephalitis, and it may be presented as a persistent hydrocephalus following the surgical removal of the lesion.

Follow-Up Imaging in Angiography-Negative Spontaneous Subarachnoid Hemorrhage

BACKGROUND

The aim of this study was to assess the diagnostic yield of follow-up investigations in aneurysm-negative subarachnoid hemorrhage (SAH) patients.

METHODS

In 109 (25%) of 435 patients with SAH and initial negative digital subtraction angiography (DSA), the diagnostic yield of repeat DSA and magnetic resonance imaging (MRI) of the brain and craniocervical junction was reviewed.

RESULTS

Of the 109 patients with an initial negative DSA, 51 (47%) had perimesencephalic (PM), 54 (50%) had nonperimesencephalic (NPM) blood distribution, and 4 (3.7%) had computed tomography-negative SAH. A delayed bleeding source was determined in 3 of 82 (3.7%) patients who underwent repeat DSA and in 1 of 5 patients who underwent a third DSA. The bleeding patterns of these patients were all NPM (n = 4). Repeat DSA did not identify a bleeding source in patients with PM-SAH. MRI of the brain and craniocervical junction after 2 days revealed a bleeding source in 1 of 105 patients (1%) in a computed tomography-negative SAH. When all diagnostic modalities, including exploratory craniotomy and MRI of the spinal axis, were considered, the rate of delayed diagnosis of the bleeding source was 6.4% (7/109). In addition to the bleeding pattern, patients with delayed diagnosis of the bleeding source were characterized by worse disease severity parameters, worse radiological grading scales, and more in-hospital complications than patients without delayed diagnosis of a bleeding source.

CONCLUSIONS

The results of this study support the use of repeat DSA in patients with NPM-SAH; however, routine repeat DSA may not be indicated in PM-SAH patients. The routine use of MRI remains controversial.

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.

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.

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.

Single-antiplatelet regimen in ruptured cerebral blood blister and dissecting aneurysms treated with flow-diverter stent reconstruction

BACKGROUND

Flow diversion treatment of ruptured cerebral aneurysms remains challenging due to the need for double-antiplatelet therapy. We report our experience with flow-diverter stent (FDS) reconstruction with single-antiplatelet therapy of ruptured cerebral blood blister and dissecting aneurysms.

METHODS

In this case series we performed a retrospective analysis of all patients with ruptured cerebral aneurysms who were treated with a phosphoryl-bonded FDS between 2019 and 2022 in a single center. Periprocedurally, all patients received weight-adapted eptifibatide IV and heparin IV. After 6-24 hours, eptifibatide was switched to oral prasugrel as monotherapy. We analyzed the rate of bleeding complications, thromboembolic events, occlusion rate and clinical outcome.

RESULTS

Nine patients with subarachnoid hemorrhage were treated, eight within 24 hours of symptom onset. Seven patients were treated with one FDS and two patients received two FDS in a telescopic fashion. Two aneurysms were additionally coil embolized. Fatal re-rupture occurred in one case; eight patients survived and had no adverse events associated with the FDS. Six patients showed complete occlusion of the aneurysm after 3 months (n=2) and 1 year (n=4), respectively. Two patients showed subtotal occlusion of the aneurysm at the last follow-up after 3 months and 6 months, respectively. Favorable clinical outcome was achieved in five patients.

CONCLUSIONS

Peri-interventional single-antiplatelet therapy with eptifibatide followed by prasugrel was sufficient to prevent thromboembolic events and reduce re-bleeding using an anti-thrombogenic FDS. FDS with single-antiplatelet therapy might be a viable option for ruptured blood blister and dissecting cerebral aneurysms.

A Case of Ruptured Carotid Traumatic Blood Blister-like Aneurysm

Ruptured cerebral aneurysms that occur in the anterior wall of the internal carotid artery (ICA) are known as blood blister-like aneurysms (BBAs); they have been reported to account for 0.3% to 1% of all ruptured ICA aneurysms. In this report, we describe the treatment of an unusual traumatic BBA (tBBA) with high-flow bypass using a radial artery graft, which resulted in a favorable outcome. A 59-year-old female suffered from an acute epidural hematoma, traumatic subarachnoid hemorrhage, and traumatic carotid-cavernous sinus fistula (tCCF) after being involved in a motor vehicle accident. Her angiography results showed tCCF and a tBBA on the anterior wall of the right ICA. On the fourth day after injury, we found rebleeding from the tBBA and performed an emergency high-flow bypass using a radial artery graft with lesion trapping as a curative procedure for the tCCF and tBBA. Postoperatively, right abducens nerve palsy appeared, but no other neurological symptoms were noted; the patient was thereafter transferred to a rehabilitation hospital 49 days after injury. Traumatic ICA aneurysms commonly occur close to the anterior clinoid process, form within 1 to 2 weeks of injury, and often rupture around 2 weeks after trauma. This case was considered rare as the ICA was likely injured and bleeding at the time of injury, resulting in a form of tBBA; this allowed early detection and appropriate treatment that resulted in a good outcome.

Long-Term Outcomes of Ruptured Blood Blister-Like Aneurysms with Multiple (≥2) Overlapping Stents and Coiling: A Single-Center Experience

OBJECTIVE

To evaluate the long-term feasibility of multiple overlapping stents (≥2) with or without coiling for treating blood blister-like aneurysms (BBAs).

METHODS

BBAs treated with stent-assisted coiling or stent-only therapy wasincluded. BBAs with atypical anatomical locations, other endovascular or surgical techniques performed, and delayed treatment (>48 hours) were excluded. Medical records of patients and procedures were retrospectively reviewed.

RESULTS

Seventeen patients with BBAs were identified, and 15 were treated with stent-assisted coiling and 2 with stent-only therapy. Triple overlapping stents were performed in seven patients, double stents in nine, and a single stent with coiling in 1. One patient experienced in-stent fibrin formation and received intra-arterial tirofiban. Complementary treatment was required in four patients. Three patients were initially treated with double (3/9) and 1 with triple stents (1/7). Three recurred in the acute period (≤6 weeks) and 1 recurred 14 months after treatment. Three of 17 patients with Hunt Hess grade 5 died early. Thirteen patients were available for long-term angiographic follow-up (13.8 ± 8.9 months). Final angiography showed complete aneurysm occlusion in all patients without in-stent stenosis or perforating vessel occlusion. Clinical follow-up data were available for all 14 surviving patients (66.8 ± 40.9 months). Eight patients had favorable outcomes, five had unfavorable outcomes, and 1 died of a subarachnoid hemorrhage-unrelated cause. Delayed infarct or hemorrhage was not documented.

CONCLUSIONS

Even in the era of flow diverter stents, the use of multiple overlapping stents with or without coiling can be a feasible alternative for treating ruptured BBAs.

Endovascular and microsurgical management of blister aneurysms: a multi-centre review

Blister aneurysms (BA) are high-risk cerebrovascular lesions accounting for 1% of intracranial aneurysms. The defective vessel wall and broad-based neck make this clinical entity difficult to treat, with high rates of re-rupture and mortality in patients presenting with acute subarachnoid haemorrhage. Blister aneurysms pose substantial challenges for both endovascular and microsurgical management. The objective of this study is to evaluate endovascular and microsurgical outcomes in intracranial blister aneurysm management across two tertiary hospitals. A review of two tertiary hospitals with a systematic imaging database search for term of "blister" in modalities from January 2010 to October 2022 was conducted. Operation reports were screened for the 5-year period since cerebral angiogram reports transitioned to surgical database. Identified reports were screened and reviewed for confirmed diagnosis by consultant neuroradiologist. A total of 21 cases of blister aneurysms managed at respective facilities were included. Sixteen cases (76%) were managed endovascularly. Four cases (19%) were managed surgically-2 with primary clipping, and 2 wrap and clipping. One case was managed conservatively (5%). Clinical outcomes were discharge disposition, aneurysm exclusion and post-operative complications. BAs have challenging considerations with high mortality and morbidity. Endovascular treatment offers a less invasive modality with lower rates of intraoperative rupture and morbidity. Mortality rates and patients discharged home were comparable. Commencement of dual anti-platelet therapy was safe in patients with flow diversion stents despite sub-arachnoid blood volume. Management of blister aneurysms is complex. Endovascular treatment shows promise for acute management but careful collaborative consideration of antithrombotic regime and requirement for further surgery should be considered.

Lumbar puncture-verified subarachnoid hemorrhage: bleeding sources, need of radiological examination, and functional recovery

BACKGROUND

The primary aim was to determine the diagnostic yield of vascular work-up, the clinical course during neurointensive care (NIC), and rate of functional recovery for patients with computed tomography (CT)-negative, lumbar puncture (LP)-verified SAH.

METHODS

In this retrospective study, 1280 patients with spontaneous SAH, treated at our NIC unit, Uppsala University Hospital, Sweden, between 2008 and 2018, were included. Demography, admission status, radiological examinations (CT angiography (CTA) and digital subtraction angiography (DSA)), treatments, and functional outcome (GOS-E) at 12 months were evaluated.

RESULTS

Eighty (6%) out of 1280 SAH patients were computed tomography (CT)-negative, LP-verified cases. Time between ictus and diagnosis was longer for the LP-verified SAH cohort in comparison to the CT-positive patients (median 3 vs 0 days, p < 0.001). One fifth of the LP-verified SAH patients exhibited an underlying vascular pathology (aneurysm/AVM), which was significantly less common than for the CT-verified SAH cohort (19% vs. 76%, p < 0.001). The CTA- and DSA-findings were consistent in all of the LP-verified cases. The LP-verified SAH patients exhibited a lower rate of delayed ischemic neurological deficits, but no difference in rebleeding rate, compared to the CT-verified cohort. At 1-year post-ictus, 89% of the LP-verified SAH patients had recovered favorably, but 45% of the cases did not reach good recovery. Having an underlying vascular pathology and an external ventricular drainage were associated with worse functional recovery (p = 0.02) in this cohort.

CONCLUSIONS

LP-verified SAH constituted a small proportion of the entire SAH population. Having an underlying vascular pathology was less frequent in this cohort, but still occurred in one out of five patients. Despite the small initial bleeding in the LP-verified cohort, many of these patients did not reach good recovery at 1 year, this calls for more attentive follow-up and rehabilitation in this cohort.

Blister-like Cerebral Aneurysm after Endovascular Catheterization: A Case Report and Literature Review

Endovascular procedures have become a mainstay in the treatment of neurovascular pathologies like arteriovenous malformations and aneurysms. Catheter-induced blister-like aneurysms (BBAs) have not been described so far in the neurosurgical literature. The authors report a rare case of a possible, catheter-induced (iatrogenic) BBA of the supra-ventral wall of the internal carotid artery (ICA) post-endovascular coiling for posterior communicating artery (PComA) aneurysm and bring the rapid progression of BBA and the grade prognosis. A 46-year-old female presented with convulsions. Imaging studies showed diffuse subarachnoid haemorrhage (SAH) and a right saccular PComA aneurysm. Endovascular coiling of the aneurysm was performed, and it was uneventful. The patient had a good outcome (modified Rankin Scale of 1) with no neurological deficits and was discharged home on day five. However, on day nine after the first ictus, she experienced a severe headache at home and was rushed to the emergency room where she collapsed. A cranial computed tomography scan showed intracerebral haemorrhage with intraventricular extension and SAH. A cerebral angiogram showed a BBA of the supra-ventral wall of the ICA. A BBA needs to be considered as a complication of an endovascular procedure that may result in rapid neurological deterioration post-coiling due to rupture. The report also illustrates the rapid and catastrophic presentation of BBA.

Long-term follow up of surgical management of blood blister-like aneurysms at non-branching sites of the internal carotid artery

To describe long-term follow-up of 25 patients who presented with subarachnoid hemorrhages due to blood blister-like aneurysms (BBAs) treated with direct clipping or clip reinforcement with or without direct neck repair. Between June 1993 and July 2009, 25 consecutive patients with ruptured BBAs of the supraclinoid internal carotid artery were retrospectively reviewed. The mean age of patients was 39.5 ± 11.3 years. The mean duration of clinical follow-up was 128.9 months (range, 85-196 months). All aneurysms were located in the supraclinoid portion of the internal carotid artery. The mean aneurysm diameter was 4.04 ± 1.3 mm on intra-operative microscopic field. Tearing of the aneurysmal neck during dissection occurred in 8 (32%) patients. Six of 7 patients with neck tearing underwent direct neck repair. Surgeons treated aneurysms via direct clipping with a Bemsheet® in 5 (20%) patients or by clip reinforcement with a silicone sheet in 20 (80%) patients. Clinical outcomes were favorable (modified Rankin Scale [mRS]: 0-2) in 21 (84%) of 25 patients. Four (16%) patients had an unfavorable outcome (mRS: 3-6). The patient with severe disability (mRS: 4) was treated with clip reinforcement and direct neck repair. Mild stenosis, moderate stenosis, and total occlusion of the parent artery were confirmed in 10 (40%) patients, 6 (24%) patients, and 1 (4%) patient, respectively. Although surgical treatment of BBAs was associated with varying degrees of parent vessel patency loss, long-term follow-up results for more than 10 years showed that direct surgical clipping or clip reinforcement with a silicone sheet appeared to be a curative surgery.

Flow Diverter Device-Assisted Coiling Treatment for Cerebral Blister Aneurysm: A Single-Center Study

Although endovascular treatment is a promising approach, blood blister-like aneurysms (BBAs) still present treatment challenges. This study aimed to assess the effectiveness and safety of flow diverter device-assisted coiling (FDDAC) for the treatment of BBAs, which are broad based and friable with a high rebleeding risk. Eight patients (five females and three males) who presented with subarachnoid hemorrhages (SAH) due to BBA ruptures between May 2020 and May 2022 were retrospectively enrolled. All patients were treated by flow diverter device (Tubridge) adjunctive coil embolization using a semi-deploying technique. The demographic information, angiographic data, interval between admission and treatment, materials, therapy, clinical outcomes (including periprocedural and intraprocedural mortality and morbidity), and follow-up results of all patients were reviewed. The mean age of the patients with BBAs was 48.5 years (range 31–62 years); aneurysm sizes ranged from 2.2 × 1.7 mm to 4.6 × 3.2 mm, and the median Hunt–Hess score was 3. All aneurysms were completely closed at follow-up, and all 8 patients had excellent clinical outcomes (modified Rankin scores = 0–2) at discharge. Angiograms showed complete aneurysm occlusion after 6 months to 1 year. In addition, there were no cases of re-rupture, re-treatment, or recurrence of the aneurysms. FDDAC is safe to use in patients with BBAs and provides an alternative treatment option for this disease.

Willis covered stent treatment for blood blister-like aneurysm: A meta-analysis of efficacy and safety

Background

Blood blister-like aneurysm (BBA) is a rare and special type of intracranial aneurysm with extremely high rates of rupture, morbidity, mortality, and recurrence. Willis Covered Stent (WCS) is a new device that is specifically designed for the treatment of intracranial complex aneurysms. However, the efficacy and safety of WCS treatment for BBA remain controversial. Thus, a high level of evidence is required to prove the efficacy and safety of WCS treatment.

Methods

A systematic literature review was performed using a comprehensive literary search in Medline, Embase, and Web of Science databases to identify studies related to WCS treatment for BBA. A meta-analysis was then conducted to incorporate the efficacy and safety outcomes, including intraoperative situation, post-operative situation, and follow-up data.

Results

Eight non-comparative studies containing 104 patients with 106 BBAs met the inclusion criteria. In the intraoperative situation, the technical success rate was 99.5% [95% confidence interval (CI), 0.958, 1.000], the complete occlusion rate was 98.2% (95% CI, 0.925, 1.000), and the side branch occlusion rate was 4.1% (95% CI, 0.001, 0.114). Vasospasm and dissection occurred in 9.2% (95% CI, 0.000, 0.261) and 0.1% (95% CI, 0.000, 0.032) of the patients, respectively. In the post-operative situation, the rebleed and mortality rates were 2.2% (95% CI, 0.000, 0.074) and 1.5% (95% CI, 0.000, 0.062), respectively. In the follow-up data, recurrence and parent artery stenosis occurred in 0.3% (95% CI, 0.000, 0.042) and 9.1% (95% CI, 0.032, 0.168) of the patients, respectively. Ultimately, 95.7% (95% CI, 0.889, 0.997) of the patients had a good outcome.

Conclusions

Willis Covered Stent could be effectively and safely applied for BBA treatment. The results provide a reference for clinical trials in the future. Well-designed prospective cohort studies must be conducted for verification.

Endovascular Treatment of Ruptured Blood Blister-like Aneurysms Using the LVIS EVO Stents

Blood blister-like aneurysms (BBAs) are rare cerebrovascular lesions that face serious challenges in surgical as well as endovascular treatment. In this paper, we present our experience in treating BBAs using the LVIS EVO stents. A total of 10 patients (mean age of 56.1 years) with 13 BBAs, who were admitted to our university hospital between April 2020 and November 2021 with a subarachnoid hemorrhage (SAH) due to aneurysm rupture, were treated using the LVIS EVO stents. Treatment of the BBAs consisted of stent-assisted coiling in four patients and stenting in six patients. The aneurysms were located within ICA (84.6%), VA (7.7%), and MCA (7.7%). Placement of the LVIS EVO stents was successful in all patients. No technical complications were observed. One in-stent thrombotic event occurred during the procedure. MRA for one-year follow-up was performed in nine patients. One patient died (Hunt and Hess Grade IV). LVIS EVO stents may be a beneficial treatment option for BBAs, as they provide high occlusion rates. However, the long-term efficacy remains uncertain.

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.

Comparison of Home-Based vs Center-Based Cardiac Rehabilitation in Hospitalization, Medication Adherence, and Risk Factor Control Among Patients With Cardiovascular Disease

IMPORTANCE

Prior studies have suggested that participation in home-based cardiac rehabilitation (HBCR) vs center-based cardiac rehabilitation (CBCR) results in similar clinical outcomes in patients with low to moderate risk; however, outcome data from demographically diverse populations and patients who are medically complex are lacking.

OBJECTIVE

To compare hospitalizations, medication adherence, and cardiovascular risk factor control between participants in HBCR vs CBCR.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study was conducted among patients in Kaiser Permanente Southern California (KPSC), an integrated health care system serving approximately 4.7 million patients, who participated in CR between April 1, 2018, and April 30, 2019, and with follow-up through April 30, 2020. Data were analyzed from January 2021 to January 2022.

EXPOSURES

Participation in 1 or more HBCR or CBCR sessions.

MAIN OUTCOMES AND MEASURES

The primary outcome was 12-month all-cause hospitalization. Secondary outcomes included all-cause hospitalizations at 30 and 90 days; 30-day, 90-day, and 12-month cardiovascular hospitalizations; and medication adherence and cardiovascular risk factor control at 12 months. Logistic regression was used to compare hospitalization, medication adherence, and cardiovascular risk factor control, with inverse probability treatment weighting (IPTW) to adjust for demographic and clinical characteristics.

RESULTS

Of 2556 patients who participated in CR (mean [SD] age, 66.7 [11.2] years; 754 [29.5%] women; 1196 participants [46.8%] with Charlson Comorbidity Index ≥4), there were 289 Asian or Pacific Islander patients (11.3%), 193 Black patients (7.6%), 611 Hispanic patients (23.9%), and 1419 White patients (55.5%). A total of 1241 participants (48.5%) received HBCR and 1315 participants (51.5%) received CBCR. After IPTW, patients who received HBCR had lower odds of hospitalization at 12 months (odds ratio [OR], 0.79; 95% CI, 0.64-0.97) but similar odds of adherence to β-blockers (OR, 1.18; 95% CI, 0.98-1.42) and statins (OR, 1.02; 95% CI, 0.84-1.25) and of control of blood pressure (OR, 0.98; 95% CI, 0.81-1.17), low-density lipoprotein cholesterol (OR, 0.98; 95% CI, 0.81-1.20), and hemoglobin A1c (OR, 0.98; 95% CI, 0.82-1.18) at 12 months compared with patients who received CBCR.

CONCLUSIONS AND RELEVANCE

These findings suggest that HBCR in a demographically diverse population, including patients with high risk who are medically complex, was associated with fewer hospitalizations at 12 months compared with patients who participated in CBCR. This study strengthens the evidence supporting HBCR in previously understudied patient populations.

Single-Cell RNA Sequencing Reveals the Pathogenic Relevance of Intracranial Atherosclerosis in Blood Blister-Like Aneurysms

Background

Intracranial non-branching site blood blister-like aneurysms (BBA) are extremely rare and vicious. Their etiology remains elusive, and no molecular study has been carried out to reveal its pathogenic relevance to intracranial atherosclerosis. To investigate its transcriptomic landscape and underlying potential pathogenesis, we performed single-cell RNA sequencing with extensive pathological validation.

Methods

In total, 12,245 cells were recovered for single-cell RNA sequencing analysis from 1 BBA and 2 saccular intracranial aneurysms (IAs). Unbiased clustering using Seurat-based pipeline was used for cellular landscape profiling. Cellchat was used to understand intracellular communications. Furthermore, 10 BBAs and 30 IAs were retrospectively collected for pathological validations like scanning electron microscopy, H&amp;E stain, Masson stain, Verhoeff Van Gielson stain, and immunofluorescence.

Results

Single-cell transcriptome profiled 14 total subclusters in 6 major groups, namely, 6 monocyte/macrophage clusters, 2 T&amp;NK clusters, 3 vascular smooth muscle cell (VSMC) clusters, 1 dendritic cell, 1 B cell, and 1 endothelial cell cluster. The only mural cell identified in BBAs was VSMC-2 cluster, while mural cells in IAs comprise most clusters of VSMCs and endothelial cells. Upregulated genes in BBA-derived VSMCs are related to arterial mineralization and atherosclerosis, such as PTX3, SPP1, LOX, etc., whereas vasodilation and physiological regulatory genes such as MGP, ACTA2, and MYL9 were conversely enriched in conventional IA-derived VSMCs. Immune cells in the BBA were predominantly macrophages, with a low fraction of T&amp;NK cells, while conventional IAs had a higher percentage of T&amp;NK. Gene enrichment analysis suggested that macrophages in BBA were highly enriched in lipid metabolism as well as atherosclerosis. Ligand–receptor interaction suggested that secretory phosphoprotein 1 (also known as osteopontin) played a major role in mediating the intracellular communication between VSMC and macrophages, especially in BBA. Pathological experiments corroborate with the bioinformatic findings and further characterized BBAs as a thin-walled thrombotic aneurysm with severe atherosclerotic lesions, where ApoE+ macrophages and OPN+ mural cells are intimately involved in the inflammation process.

Conclusions

The preexisting intracranial atherosclerosis might predispose the parent artery to the pathogenic occurrence of BBAs. These data shed light on the pathophysiology of intracranial aneurysms and might assist in the further resolution of the complexity in aneurysm pathogenesis.

Application of the Willis Covered Stent in the Treatment of Blood Blister-Like Aneurysms: A Single-Center Experience

Objective

To evaluate the effectiveness of the Willis covered stent (WCS) in the treatment of ruptured blood blister-like aneurysms (BBAs) of the internal carotid artery (ICA).

Method

The clinical data of 16 patients consecutively treated with WCSs from December 2015 to January 2019 were retrospectively analyzed. Clinical data and angiographic findings were analyzed by two experienced neuroradiologists and neurosurgeons, including age, sex, Hunt and Hess (H&H) grade at admission, modified Rankin scale (mRS) score, aneurysm size, and location, the diameter of the patent artery in proximal and distal ends, stent size, rate of aneurysm occlusion, procedure-related complications, and follow-up.

Results

All the 16 patients (five males, 11 females) with ICA BBAs underwent WCS deployment successfully. The median age was 49 years (range, 29–72). All patients had complete aneurysm occlusion on immediate postoperative angiography. Anterior choroidal artery (AChA) was occluded in one patient accidentally while no obvious neurological dysfunction was observed. However, this patient underwent subarachnoid hemorrhage 1 day after the treatment; endoleak and aneurysm recurred, and the patient died 10 days later. Therefore, the effective rate of WCS treatment was 93.8% (15/16), and procedure-related complications rate was 6.3% (1/16). Moreover, one patient was urgently treated because of accidental aneurysm rupture after anesthesia, and external ventricular drainage was then performed postoperatively. Another patient developed coma and hemiplegia 3 days after treatment, with emergency angiography showing in-stent thrombosis and ICA occlusion which was recanalized with arterial rt-PA thrombolysis; the patient recovered completely. The clinical follow-up period was 3–30 months in 14 patients. The mRS scores were 0 in 12 patients (85.7%) and 4 in 1 case (7.1%), while 1 patient (7.1%) died 6 months postoperatively for unknown reasons. Angiographic follow-up was performed in 13 patients, and no recurrence was observed. However, ICA occlusion without neurological deficit was observed in one patient.

Conclusion

Based on careful preoperative evaluation, appropriate WCS size selection, and precise surgical operation, WCSs may provide an alternative and effective solution for blood BBAs via aneurysm isolation and ICA reconstruction immediately; However, further follow-up studies with larger samples are required.

Angiographically Occult Subarachnoid Hemorrhage: Yield of Repeat Angiography, Influence of Initial CT Bleed Pattern, and Sources of Diagnostic Error in 242 Consecutive Patients

BACKGROUND AND PURPOSE

Nearly 20% of patients with spontaneous SAH have no definitive source on initial DSA. The purpose of this study was to investigate the timing and yield of repeat DSA, to clarify the influence of initial CT bleed pattern, and to characterize sources of diagnostic error in this scenario.

MATERIALS AND METHODS

We evaluated the yield of repeat DSA and clinical outcomes stratified by hemorrhage pattern on CT in consecutive patients with nontraumatic SAH with negative initial DSA findings at a referral center. Cases in which the culprit lesion was subsequently diagnosed were classified as physiologically occult (ie, undetectable) on the initial DSA, despite adequate technique and interpretation or misdiagnosed due to operator-dependent error.

RESULTS

Two hundred forty-two of 1163 (20.8%) patients with spontaneous SAH had negative initial DSA findings between 2009 and 2018. The SAH CT pattern was nonperimesencephalic (41%), perimesencephalic (36%), sulcal (18%), and CT-negative (5%). Repeat DSA in 135/242 patients (55.8%) revealed a source in 10 patients (7.4%): 4 saccular aneurysms, 4 atypical aneurysms, and 2 arteriovenous shunts. The overall yield of repeat DSA was 11.3% with nonperimesencephalic and 2.2% for perimesencephalic patterns. The yield of the second and third DSAs with a nonperimesencephalic pattern was 7.7% and 12%, respectively. Physiologically occult lesions accounted for 6/242 (2.5%) and operator-dependent errors accounted for 7/242 (2.9%) of all angiographically occult lesions on the first DSA.

CONCLUSIONS

Atypical aneurysms and small arteriovenous shunts are important causes of SAH negative on angiography. Improving DSAs technique can modestly reduce the need for repeat DSA; however, a small fraction of SAH sources remain occult despite adequate technique. These findings support the practice of repeating DSA in patients with a nonperimesencephalic SAH pattern.

Early surgical versus endovascular repair of ruptured blood-blister aneurysm of the internal carotid artery: a single-center 20-year experience

OBJECTIVE

Early repair of ruptured blood-blister aneurysms (BBAs) of the internal carotid artery (ICA) remains challenging. Although both surgical and endovascular therapies have been established, their relative superiority remains debated. The authors assessed their single-center experience and compared early deconstructive versus reconstructive repair and early reconstructive surgical versus endovascular repair of ruptured BBAs of the ICA.

METHODS

The study included patients who underwent repair of ruptured BBAs of the ICA within 1 week after the ictus during a 20-year period. Multiple variables were recorded, including clinical state, severity of subarachnoid hemorrhage (SAH), characteristics of the BBA, treatment details, complication profile, need for secondary treatment, and clinical outcome.

RESULTS

In total, 27 patients underwent early surgical (n = 16) or endovascular (n = 11) repair of BBAs at a median of 24 hours (range 9-120 hours) after the ictus during the period from September 2000 to June 2021 (20.4 years). Primary deconstructive repair (n = 6) without bypass was accompanied by middle cerebral artery (MCA) territory infarction in 5 of 6 (83%) patients and a high mortality rate (4/6 [67%]). Among the 21 patients who underwent early reconstructive repair, surgery was performed in 11 patients (clipping in 6 and clip-wrapping in 5 patients) and endovascular repair in 10 patients (flow diversion in 7 and stent/stent-assisted coiling in 3 patients). No differences were found in complication profiles or clinical outcomes between the surgical and endovascular groups. The mortality rate was low (2/21 [9.5%]), with 1 fatality in each group.

CONCLUSIONS

From the authors' experience, both surgical and endovascular approaches permitted reconstructive repair of ruptured BBAs of the ICA, with no modality proving superior. Reconstructive treatment is preferable to ICA sacrifice, and if sacrifice is chosen, it should be accompanied with bypass surgery or delayed to the phase when cerebral vasospasm has resumed. The rare occurrence of this disease calls for prospective multicenter studies to improve treatment and delineate which modality is preferable in individual cases.

The role of microsurgery for poor-grade aneurysmal subarachnoid hemorrhages in the endovascular era

BACKGROUND

Poor-grade aneurysmal subarachnoid hemorrhage (PGASAH) is associated with high mortality and morbidity regardless of treatment. Herein, we re-evaluate the safety and efficacy of microsurgical treatment for managing PGASAH patients in the current endovascular era.

METHODS

We retrospectively reviewed 141 consecutive patient records in a single institution who underwent microsurgical (n = 80) or endovascular (n = 61) treatment for PGASAH.

RESULTS

Baseline characteristics were similar, except for more intracerebral hematomas (46.3% vs 24.6%, p = 0.009), fewer intraventricular hemorrhages (26.3% vs 59%, p < 0.001), and fewer posterior circulation aneurysms (5.1% vs 44.3%, p < 0.001) in the microsurgery group. Decompressive craniectomy (58.5% vs 24.6%, p < 0.001) and shunt-dependent hydrocephalus (63.7% vs 41%, p = 0.01) were more common for microsurgery, while procedural ischemic complications were less common (5% vs 24.6%, p = 0.001). Both early (12.5% vs 32.8%, p = 0.006) and late mortality rates (22.5% vs 39.3%, p = 0.041) were lower for microsurgery, and favorable 12-month outcomes (modified Rankin scale = 0-2) were better (62.5% vs 42.6%, p = 0.026). Multivariate analysis revealed that advanced age, neurological grade, modified Fisher grade, larger aneurysm size, rebleeding, and cerebral infarctions were independent predictors of poor outcome. Microsurgery fared marginally better than endovascular treatment (OR: 2.630, 95% CI: [0.991-6.981], p = 0.052).

CONCLUSIONS

Timely and efficient treatment, either via open microsurgery or endovascular surgery, provided favorable outcomes for over half of PGASAH patients in this series. Therefore, early treatment should be offered to all PGASAH patients regardless of clinical and/or radiological factors. Microsurgery remains an effective treatment modality for selected PGASAH patients in the endovascular era.

Flow diversion for acutely ruptured intracranial aneurysms treatment: A retrospective study and literature review

OBJECTIVE

Flow diversion is becoming an increasingly established practice for the treatment of acutely ruptured intracranial aneurysms. In this study the authors present a literature review and meta-analysis, adding a retrospective review of institutional registry on emergency treatment of aRIA with flow diverter stent.

MATERIALS AND METHODS

A systematic search of PubMed, SCOPUS, Ovid MEDLINE, and Ovid EMBASE was performed on April 20^th, 2021, extrapolating 35 articles. R language 'meta' and 'metafor' packages were used for data pooling. The DerSimonian-Laird model was used to calculate the pooled effect. The I² value and Q statistic evaluated study heterogeneity. Additionally, the authors retrospectively reviewed their institutional database for the treatment and outcomes of all patients with acutely ruptured intracranial aneurysms treated with flow diverter stent placement from May 2010 to November 2020 was performed.

RESULTS

From the systematic literature review and meta-analysis, the pooled proportion of complete aneurysm occlusion was 78%, with a pooled rate of 79%, 71%, 80%, and 50% for dissecting, saccular, fusiform, and mycotic aneurysms, respectively. The pooled proportion of aneurysm rebleeding and intrastent stenosis was 12% and 15% respectively, for a total of 27% rate. The analysis of authors retrospective register showed an overall mortality rate of 16.7% (3/18), with a low but not negligible postprocedural rebleeding and intrastent thrombosis rates (5.6% and 11.1% respectively).

CONCLUSION

Although increasingly utilized in the management of selected patients with acutely ruptured intracranial aneurysms, flow diversion for acutely ruptured intracranial aneurysms treatment presents rebleeding and intrastent stenosis rates not negligible.

Endovascular Management of Hemorrhagic Stroke

Significant advances in endovascular neurosurgery tools, devices, and techniques are changing the approach to the management of acute hemorrhagic stroke. The endovascular treatment of intracranial aneurysms emerged in the early 1990s with Guglielmi detachable coils, and since then, it gained rapid popularity that surpassed open surgery. Stent-assisted coiling and balloon remodeling techniques have made the treatment of wide-necked aneurysms more durable. With the introduction of flow diverters and flow disrupters, many aneurysms with complex geometrics can now be reliably managed. Arteriovenous malformations and fistulae can also benefit from endovascular therapy by embolization using n-butyl cyanoacrylate (NBCA), Onyx, polyvinyl alcohol (PVA), and coils. In this article, we describe the role of endovascular treatment for the most common causes of intracerebral and subarachnoid hemorrhages, particularly ruptured aneurysms and vascular malformations.

Coil Embolization of Traumatic Ophthalmic Artery Aneurysm: Case Report

We describe the case of a 57-year-old man who had traumatic subarachnoid hemorrhage (SAH) with a delayed growth of an ophthalmic artery aneurysm. Initially, computed tomography angiography did not show any evidence of aneurysmal dilatation, but digital subtraction angiography (DSA) after 3 days showed small aneurysmal dilatation or dissection of a presumed lesion. Early intervention or surgery was difficult because of the patient's unstable condition. The SAH was completely resolved within 7 days. Follow-up DSA was performed 2 weeks later and it revealed an increasing size and shape change. We treated the patient with coil embolization, partially filling the aneurysm to save the ophthalmic artery. DSA performed 6 months later indicated that the aneurysm was completely embolized, sparing the ophthalmic artery. In traumatic SAH, delayed growth of the aneurysm should always be considered, and follow-up imaging should be performed. Partial embolization to save the ophthalmic artery can be one of the treatment modalities for selected patients.

Reduced M2 macrophages and adventitia collagen dampen the structural integrity of blood blister-like aneurysms and induce preoperative rerupture

Objective

Blood blister–like aneurysms (BBAs) are extremely rare aneurysms. They are predisposed to preoperative rerupture with a high case‐fatality rate. Here, we attempt to interrogate the distinct clinicopathology and the histological basis underlying its clinical rerupture.

Methods

Three middle meningeal arteries, 11 BBA (5 reruptured, 6 non‐rerupture) and 19 saccular aneurysm samples were obtained for histopathological investigation. Three reruptured BBAs, 3 non‐reruptured BBAs and 6 saccular (3 ruptured, 3 unruptured) aneurysms were obtained for quantitative flow cytometry analysis.

Results

Compared with true saccular aneurysms, the BBA aneurysm wall lacks arterial stroma cells including CD31+ endothelial cells and α‐SMA + smooth muscle cells. Only fibroblasts and adventitial collagen were observed in the BBA aneurysm wall. Meanwhile, BBAs were enriched with infiltrated inflammatory cells, especially polarized macrophages. Based on the rerupture status, those reruptured BBAs showed drastically reduced fibroblasts and adventitia collagen. Moreover, M2‐polarized macrophages were observed dominant in BBAs and exhibit repairing cellular functions based on their interplays with arterial fibroblasts. Reduced M2 macrophages and arterial tissue repairing modulation may be responsible for the decreasing collagen synthesis and fibrosis repairment, which potentially dampens the aneurysm integrity and induces BBA aneurysm reruputre.

Conclusions

BBAs poses histopathological features of occult pseudoaneurysms or dissecting aneurysms. Reduced M2 macrophages and adventitia collagen may dampen the structural integrity of BBAs and induce preoperative rerupture.

Wrap-Clipping for Patients with Ruptured Blood Blister-Like Aneurysms of the Internal Carotid Artery: Case Series and Literature Review

OBJECTIVE

 Blood blister-like aneurysms (BBAs) of the internal carotid artery (ICA) are challenging to treat. We assessed the clinical and radiologic outcomes in patients with ruptured BBAs of the ICA treated with wrap-clipping.

METHODS

 From November 2016 to January 2020, the clinical and radiologic data of patients with subarachnoid hemorrhage (SAH) caused by ICA BBAs who underwent wrap-clipping were retrospectively analyzed. The clinical outcomes were evaluated according to the modified Rankin Scale (mRS). Radiologic follow-up examinations included digital subtraction angiography (DSA), computed tomography angiography (CTA), and magnetic resonance angiography (MRA).

RESULTS

 Seven patients were enrolled in this study. All BBAs were wrap-clipped successfully, including two BBAs that exhibited intraoperative bleeding and required balloon-assistance during surgery. All patients had favorable clinical outcomes during follow-up. Among the six patients who completed the radiologic follow-up visit, one patient presented ICA occlusion at the 6-month DSA follow-up, but no neurologic dysfunction was noted. We did not observe the progression of ICA stenosis in other patients.

CONCLUSION

 All BBAs in this study were wrap-clipped successfully and completely occluded. Wrap-clipping is effective for BBAs of the ICA and has favorable clinical outcomes. A multicenter study with a large sample size and a longer radiologic follow-up is necessary.

Standalone Flow Diversion Therapy Effectively Controls Rebleeding of Acutely Ruptured Internal Carotid Artery Trunk (Nonbranching) Microaneurysms

Flow diversion is a promising option in selected patients with acutely ruptured microaneurysms. In this article, we reviewed our experience. Patients with acute spontaneous subarachnoid hemorrhage (SAH) after rupture of a blister-like or saccular microaneurysm (≤2 mm maximal diameter) at a nonbranching ICA site treated from January 2016 to June 2019 using flow diversion as standalone therapy were included in this study. An EVD was usually placed preventively. Antiplatelet effects of pre-procedure DAPT were evaluated (target PRU, 80–160). After the intervention, DAPT was continued for ≥6 months, aspirin—indefinitely. Angiographic controls were obtained. Fifteen patients (12 female; mean age, 46.4 years) with 15 ruptured ICA microaneurysms (mean diameter, 1.8 mm) were included. An EVD was placed in 12 patients (75%) before DAPT administration and stenting. PRU values immediately before FDS were 1–134 (mean, 72.1). One patient died 27 days after flow diversion due to a suspected fulminant pulmonary embolism. Aneurysms were completely occluded at the 6–12-month angiographic follow-up in 14/14 surviving patients, with no rebleeding at a mean of 14 months. Late mRS was 0–2 in 13/14 patients and 3 in one due to sequelae of the original hemorrhage. Flow diversion provided robust aneurysm rebleeding control. Angiographic follow-up confirmed complete aneurysm occlusion in all the cases.

Application of the Willis covered stent in the treatment of internal carotid artery blood blister-like aneurysms

The optimal treatment for blood blister-like aneurysm (BBA) has not yet been determined, and BBA has a high recurrence rate after stent-assisted embolization. The purpose of the present study was to evaluate the safety and feasibility of patients with BBA rupture in the acute phase or patients with BBA who have recurrence after stent-assisted coil embolization. Eight patients (8 women, mean age 50.3 ± 3.7 years) who presented with ruptured BBA or recurrence BBA that had been treated by stent-assisted embolization (5 patients after primary treatment of stent-assisted embolization) were retrospectively reviewed. Clinical follow-up was performed at 1 year after endovascular treatment. All patients were successfully treated with the WCS, and immediate postoperative angiography showed that the aneurysms were completely isolated. The ophthalmic artery was covered by WCS in one patient; however, this patient did not show any clinical visual field or vision symptoms. Procedure-related complications such as aneurysm rupture, vasospasm, acute thrombosis, or thromboembolism did not occur in any case. All patients were followed up for 1 year after endovascular treatment, and they were in good condition without recurrence. One patient developed delayed bleeding at the right temporal lobe. All patients had good clinical prognosis (modified Rankin Scale score ≤ 2). WCS implantation may be a safe and feasible strategy for patients with BBA rupture in the acute phase and patients with BBA who have recurrence after stent-assisted coil embolization and is a promising option worth exploring.

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.

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.

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.

Cerebral vasospasm resulted in "stent shortening" after pipeline assisted coil embolization for blood blister aneurysms

Blood blister aneurysms (BBAs) are intracranial arterial lesions appearing in nonbranching sites of the supraclinoid internal carotid artery as well as the basilar artery. Endovascular treatment of BBAs is still not well established because of the rarity of these lesions. We report incidences of BBAs with associated vasospasms. Treatment of the BBAs and associate vasospasms with single Pipeline Flex embolization device (PLED) assisted coiling resulted in seemly shorting of the PLEDs in 3 patients.A retrospective analysis of patients with BBAs who were treated with single PLED assisted coiling from July 2018 to October 2019 was conducted. Patients' ethnic and medical records, aneurysmal characteristics, intraoperative-rupture, cerebral vasospasm (CVS), postprocedure contrast filling, follow-up imaging, and results were analyzed. Neurological examination at baseline and outcome based on modified Rankin scale (mRS) at discharge as well as follow-ups were also documented.Six patients consisting of 5 females and 1 male, with a mean age of 48.3 years (range from 34-67) were identified during our analysis. All the BBAs were located in nonbranching site of supra-clinoidal segment of internal carotid artery with a mean neck width of 4.5 mm and mean aneurysm size of 4.23 mm. PLED assisted coiling's were performed in all of them. CVS was observed in 3 patients while 1 patient had an intraoperative-rupture of the BBA. Postprocedure contrast filling was still present in 1 patient. All the patients had good outcomes with discharge and follow-up mRS scores ≤ 2 except 1 patient with mRS score = 3 with aphasia.PLED assisted endovascular coiling is very safe and efficient in treating patients with BBAs. Resolution of CVSs after treatment made the PLEDs seemly shorter. Furthermore, a combination of arterial lengthening after gaining their tensile strength back and radical expansion of the PLED could account for the shortening.

Microsurgical Clip Trapping of Dorsal Internal Carotid Artery Blister Ruptured Aneurysm: 2-Dimensional Operative Video

Dorsal internal carotid artery (ICA) blister aneurysms are an uncommon aneurysm variant constituting 0.3% to 1% of intracranial aneurysms and can be due to ulceration, atherosclerosis, or dissection.1-3 Despite its rarity, it carries a high risk of rupture with an estimation of 0.9% to 6.5% among intracranial aneurysms.1,2 Blister aneurysms are small in size, have no distinguishable neck, and have a friable wall that can easily rupture if manipulated, hence the difficulty in its treatment utilizing both microsurgical and endovascular techniques.1,2,4-6 Endovascular coiling of these lesions may not be adequate due to the broad-based size; stenting requires the use of antiplatelet medications, which could lead to rebleeding; flow diversion takes longer to exert its treatment effect.1,4 Conversely, microsurgical management carries a higher intraoperative rupture rate.2 Microsurgical options include clipping, clip reconstruction, trapping with bypass, and wrapping.4,7 We present a case of a 38-yr-old man who presented with a ruptured right dorsal ICA blister aneurysm treated with microsurgical trapping with intraoperative flow measurements. We demonstrate how the use of quantitative intraoperative flow measurements allows confident sacrifice of the supraclinoid ICA. We also demonstrate in contrast another case example of utilizing a clip-graft repair. The patient remained unchanged with an intact neurological exam, and postoperative imaging showed no aneurysm remnant and patent anterior choroidal artery. We review the literature and management of dorsal ICA aneurysms.8-15 We also review the technical nuances and different endovascular and microsurgical treatments that can be used for this condition.  The patient gave informed consent for the procedure and verbal consent to the publication.

Endovascular treatment of blood blister-like aneurysms of internal carotid artery: Stent-assisted coiling and pipeline flow diversion

OBJECTIVE

To report the stent-assisted coil embolization and flow diversion treatments of blood-blister-like aneurysms based on the theory of acute dissection of the internal carotid artery.

PATIENTS AND METHODS

From July 2016 through July 2020, 27 patients presenting with subarachnoid hemorrhage (SAH) due to rupture of internal carotid artery blood blister-like aneurysms were subjected to endovascular treatment with stent-assisted coiling or Pipeline flow diversion. Clinical outcomes were evaluated using modified Rankin Scale score (mRS).

RESULTS

A proximal stenosis caused by angiopathology adjacent to aneurysms were found on internal carotid artery angiograms in all 27 cases. The angiopathology combining with the aneurysms implement that acute dissection of the supraclinoid segment of the internal carotid artery indicated the pathogenesis of blood blister-like aneurysm formation. All aneurysms were treated successfully with alleviation of the adjacent angiopathology after stenting on angiograms. During 1-12 months, mean 3.5 months, complete aneurysm obliteration without adjacent stenosis were found in 25(92.6%) patients. Two (7.4%) cases of recanalization were retreated with complete obliteration at 1 week and 3 months after initial treatment. Clinical mRS 0 and 1 outcomes were observed in 23(85.2%) patients, mRS 2 in 3(11.1%) patients and mRS 6 in 1(3.7%) not related to aneurysm treatment during follow-up.

CONCLUSIONS

Acute focal dissection of supraclinoid segment of internal carotid artery underlies the development of blood blister-like aneurysm. Stent-assisted coiling and flow diversion treatments constitute appropriate treatment based on the arterial dissection pathology.

Microsurgical Clipping of Carotid-Ophthalmic Tandem Aneurysms: Case Report and Surgical Nuances

Tandem intracranial aneurysms (TandIAs) are rare but inherently complex, and special technical considerations are required for their surgical management. The present case highlights the key surgical aspects of two carotid-ophthalmic TandIAs incidentally found in a 60-year-old female. Both the aneurysms were superiorly projecting, regular in size, and involved the left ophthalmic segment of the internal carotid artery (ICA). The minimum distance between the necks was 3 mm. The patient underwent microsurgery because of the reported major complications rate of the endovascular treatment in the case of a very short minimum distance between the TandIAs. After cervical ICA exposure, both the aneurysms were excluded through a pterional approach. Intradural anterior clinoidectomy and unroofing of the optic canal allowed the mobilization of the left optic nerve. The more distal aneurysm was clipped before the opening of the distal dural ring of the ICA. The proximal aneurysm was clipped with two straight clips stacked perpendicular to the ICA. A small remnant was intentionally left to avoid the stenosis of the ophthalmic artery. Postoperative angiography showed the exclusion of both the aneurysms with a small dog-ear of the more proximal one. The patient was discharged neurologically intact and, after one year, the remnant remained stable. Microsurgical clipping is a definitive and durable treatment for carotid-ophthalmic TandIAs. In the case of a very short minimum distance between the aneurysms, the distal one should be clipped first to make the anterior clinoidectomy, opening of the distal dural ring of the ICA, and clipping of the more proximal aneurysm easier.

Stent-in-stent technique for the management of blood blister-like basilar apex aneurysms

Blood blister-like basilar apex aneurysms are rare thin-walled vascular lesions with a poorly defined aneurysmal neck. We present two patients with ruptured blister aneurysms of the basilar apex who were treated using the stent-in-stent technique. Long-term follow-up showed persistent and complete occlusion of the aneurysms without radiographically or neurological complications. There is no optimal treatment of choice for the basilar apex blood blister-like aneurysms. Double- or triple-stent placement using the stent-in-stent technique can be a safe and feasible option for these uncommon and challenging intracranial aneurysms.

Lesion Trapping with High-Flow Bypass for Ruptured Internal Carotid Artery Blood Blister-Like Aneurysm Has Little Impact on the Anterior Choroidal Artery Flow: Case Series and Literature Review

OBJECTIVE

To examine the relationship between trap location and cerebral infarction in the anterior choroidal artery (AChA) region and associated risks in ruptured internal carotid artery blood blister-like aneurysm (BLA) treatment with high-flow bypass and lesion trapping.

METHODS

We included 26 patients diagnosed with BLAs and treated with high-flow bypass and trapping. We examined clinical characteristics including age, aneurysm trap location, final prognosis, cerebral infarction on postoperative magnetic resonance imaging, and modified Rankin Scale score at discharge. We also searched the literature for similar studies.

RESULTS

The modified Rankin Scale score at discharge was 0-2 in 20 patients, 3-5 in 2 patients, and 6 in 2 patients. In 19/26 patients (73.1%), the trapped segment was between the posterior communicating (PcomA) and the ophthalmic arteries. In 2 patients (7.7%), the trapped segment included the PcomA and the AChA; in 4 patients (15.4%), the trapped segment was within the PcomA. In these patients, the PcomA was occluded, and blood from the high-flow bypass flowed out to the AChA alone. No patient showed cerebral infarction. Our systematic review identified 70 patients. Of all 96 patients, 12 had AChA cerebral infarction; however, the infarction affected the prognosis of only 2 patients.

CONCLUSIONS

When treating BLAs with high-flow bypass and lesion trapping, the frequency of AChA cerebral infarction is low even when the PcomA is occluded, leaving the AChA as the only outflow vessel during high-flow bypass. However, PcomA occlusion may be associated with risks when treating patients with advanced arteriosclerosis near C1-2.

The formation mechanism of acute dissection of blood blister-like aneurysm and its implication of endovascular treatment

BACKGROUND

Acute mural dissection of the anterior wall of the internal carotid artery which may contribute to the development of blood blister-like aneurysms (BBLAs) was postulated, and stenting or flow diversion treatment across the soi-disant aneurysm was reported in this study.

METHODS

From December 2016 to December 2018, 8 patients presenting with subarachnoid hemorrhage (SAH) due to BBLA were subjected to endovascular treatment with stent-assisted coiling. Clinical outcomes were evaluated using a clinical outcome score scale.

RESULTS

Based on angiograms, pathologic change involving the supraclinoid segments of the internal carotid artery (ICA) adjacent to BBLA was found in all patients. This pathologic change meant a focal dissection of the supraclinoid segment of the ICA which constituted the pathogenesis of BBLAs. Closed-cell, open-cell, and braided stents were used in 1, 1, and 6 patients, respectively. Complete obliteration was achieved following endovascular treatment among all 8 patients harboring BBLA. One re-bleeding successive to a closed-cell stent across the aneurysmal neck was observed. Follow-up angiograms revealed stable complete exclusion of all BBLAs from the parent vessel at 3 to 8 months. All patients had a favorable clinical outcome score of 0-1.

CONCLUSIONS

Acute dissection of a focal point of the intracranial vessels underlies the development of BBLAs. Open-cell and braided-cell stent-assisted coiling may constitute appropriate treatment due to good apposition against the vascular walls. Adjunctive coils may facilitate immediate complete occlusion of BBLAs.

Usefulness of 3D High-resolution Vessel Wall MRI in Diffuse Nonaneurysmal SAH Patients

PURPOSE

In 15-20% of patients with nontraumatic diffuse subarachnoid hemorrhage (SAH), the initial conventional angiography does not reveal a causative vascular abnormality, such as intracranial aneurysm. In this study, we evaluated clinical utility of 3D high-resolution vessel wall magnetic resonance imaging (HR-VWI) in patients with diffuse nonaneurysmal SAH.

METHODS

A total of 17 patients with diffuse nonaneurysmal SAH were included in this retrospective study. We characterized demographics and HR-VWI findings and reviewed the clinical management and outcomes.

RESULTS

Of the patients 14 (14/17; 82.4%,) showed abnormal findings on HR-VWI, including 5 with intracranial dissections (29.4%), 3 with blood blister-like aneurysm (17.6%), 1 with ruptured fusiform aneurysm (5.9%), and 5 with focal nodular wall enhancement without unclassified pathology (29.4%). Of these patients were treated with endovascular management. Most patients (16/17) had a favorable modified Rankin scale scores of 0-2 on discharge.

CONCLUSION

The 3D HR-VWI revealed various hidden pathologies, such as intracranial arterial dissection, blood blister-like aneurysm, and fusiform aneurysm in patients with diffuse nonaneurysmal SAH. In addition, 3D HR-VWI had an impact on the management of SAH. The 3D HR-VWI can be a complementary diagnostic method for patients with diffuse nonaneurysmal SAH in a research or clinical setting.

Internal Carotid Artery Blister Aneurysm: Review of Endovascular Techniques

Cerebral blister aneurysms are very difficult vascular lesions in terms of accurate diagnosis as well as proper management strategy for vascular neurosurgeons and neurointerventionists. Histopathological analysis has revealed their nature to be more akin to pseudoaneurysms in comparison to the typical berry aneurysms. This explains their fragile nature, with high probability of rerupture and regrowth during the follow-up if not addressed properly. Even though surgical approaches have evolved over the years to minimize intraprocedural rupture and recurrence, they still have relatively high morbidity as well as mortality in comparison to endovascular treatment. Over the last few years, endovascular treatment has evolved significantly, with introduction of new devices and techniques. Focus of the endovascular management has shifted from the deconstructive techniques to reconstructive ones with parent artery preservation. Recent introduction of flow diverter technology has enabled neurointerventionists to manage these difficult lesions with more confidence in terms of avoiding rerupture and recurrence. Flow diverter (FD) use in blister aneurysm resulted in high-technical success, complete aneurysm occlusion, and less complications in comparison to other reconstructive techniques like simple coiling, stent assisted coiling, and overlapping/monotherapy stent placement. Few debatable issues like use of dual antiplatelets in the setting of acute subarachnoid hemorrhage (SAH), timing of drugs in relation to procedures, single/overlapping devices, and concerns during cerebral vasospasm phase need further detailed analysis and standardized protocols. In this article, we have done a review of different endovascular treatment options in the management of internal carotid artery blister aneurysms with special focus on FD and issues related to it.

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.

Comparison of clinical and histopathological characteristics of short-term progressive and non-progressive blood blister-like aneurysms

BACKGROUND

Many blood blister aneurysms (BBAs) have been documented with a rapid progression history in repeated angiography. The underlying mechanism and clinical significance remained elusive. This current study aims to clarify the clinical and histopathological differences between short-term progressive BBA and non-progressive BBAs.

METHODS AND MATERIALS

Eighty-one patients with BBAs were consecutively included for this single-center retrospective analysis. Clinical and radiological data on these patients were retrieved from 2017 to 2019. BBAs were defined as either progressive or non-progressive based on observed growth based on repeated imaging. Histopathological examinations of a saccular aneurysm, a progressive BBA, and a non-progressive BBA were conducted using representative aneurysm samples.

RESULTS

Among all enrolled patients, 26 of the them were identified with progressive BBAs, while the other 55 with non-progressive BBAs. Progressive BBAs were diagnosed significantly earlier in angiography (3.36 ± 0.61 vs. 6.53 ± 1.31 days, p < 0.05) and showed a higher presence rate of daughter sacs (61.5 vs. 38.2%, p < 0.05). Three different progression patterns were identified. BBAs that developed daughter sac enlargement are diagnosed significantly later than BBAs exhibiting other progression patterns. Patients with progressive and non-progressive BBAs exhibited similar overall clinical outcomes and incidence for complications. For patients with non-progressive BBAs, microsurgery appears to be inferior to endovascular treatment, while for patients with progressive BBAs, the short-term outcomes between microsurgery and endovascular treatment were identical. Histopathological analysis revealed that both subtypes shared a similar pseudoaneurysms structure, but non-progressive BBAs had more histologically destructed aneurysm wall with less remnant fibrillar collagen in adventitia.

CONCLUSIONS

Progressive and non-progressive BBAs may not be distinct pathological lesions but represent different stages during the BBA development. Early intervention, regardless of treatment methods, is recommended for salvageable patients with progressive BBAs, but microsurgery should be performed with caution for non-progressive BBAs due to increased surgical risk.

Is Stent-Assisted Coil Embolization for the Treatment of Ruptured Blood Blister-Like Aneurysms of the Supraclinoid Internal Carotid Artery Effective? : An Analysis of Single Institutional Experience with Pooled Data

Objective

Given the high risk of rebleeding and recurrence of blood blister-like aneurysms (BBAs), we treated ruptured BBAs of the internal carotid artery (ICA) with stent-assisted coil embolization (SAC). This study aimed to evaluate the efficacy and safety of SACs.

Methods

We retrospectively reviewed clinical and radiological data from eight patients with ruptured BBAs of the supraclinoid ICA. The modified Rankin Scale (mRS) was used to assess clinical outcomes, while radiological outcomes were evaluated on angiographs. For a pooled analysis, data from literature reporting the outcomes of ruptured BBAs treated with SAC were collected and analyzed in conjunction with our data.

Results

In our cohort, the mean Raymond classification score was 1.57±0.53 immediately after initial endovascular treatment. There were no perioperative complications or rebleeding events during the follow-up period. The mean mRS score at patient discharge was 1.00±0.81 and improved to 0.28±0.48 by the last follow-up day. The recurrence rate was 25% with an asymptomatic presentation and successful treatment with multiple stent insertion. Pooled analysis of 76 cases of SAC revealed a complete occlusion rate immediately after treatment of 54.8%, rebleeding rate 7.94%, and recurrence rate 24.2%. Good clinical outcomes with mRS score 0–2 were observed in 89.9% by the last clinical follow-up. Total mortality rate was 7.7%.

Conclusion

This treatment appears to not only minimize the hemodynamic burden on the fragile dome specific to this type of aneurysm, but also provides an opportunity for safe and effective treatment in recurrent cases.

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.

Stent-Assisted Coil Embolization of Ruptured Blood Blister-Like Aneurysm of the Basilar Artery: A Case Report and Literature Review

Objective

Blood blister-like aneurysms (BBA) often develop on the anterior wall of the internal carotid artery, and few cases have been reported at other sites. We report a case of stent-assisted coil embolization in the acute phase for a ruptured BBA of the basilar artery.

Case Presentation

A 53-year-old woman underwent emergency stent-assisted coil embolization for subarachnoid hemorrhage due to a ruptured BBA in the main trunk of the basilar artery. Seven months after the operation, cerebral angiography confirmed no recurrence and a good clinical course.

Conclusion

Stent-assisted coil embolization for BBA may be one treatment option.