Endovascular treatment of intracranial infectious aneurysms

Efficacy of Endovascular Glue Embolization in Treating Ruptured Intracranial Mycotic Aneurysms: A Single Center Experience

PURPOSE

Intracranial mycotic aneurysms (IMAs), rare and often life-threatening, result from arterial wall infections typically caused by bacteria such as Staphylococcus and Streptococcus. The standard treatment for ruptured aneurysms is not well-defined and often individualized. This study investigates the efficacy of endovascular glue embolization in managing ruptured IMAs, based on our center's experience.

MATERIALS AND METHODS

A retrospective analysis was conducted for ruptured IMAs treated with glue embolization between January 2016 and December 2023. The procedure involved aneurysm sac and parent vessel occlusion with glue delivery. Data included patient demographics, clinical presentations, and neuroimaging. Clinical outcomes were assessed using the modified Rankin scale (mRS) at 3 months, and angiographic follow-up was conducted at 6 months.

RESULTS

The study included 28 patients, predominantly male (64.3%), with a mean age of 48 years. Headache was the primary symptom in 92.9% of cases, and positive blood/cerebro spinal fluid cultures were found in 82.14% of cases. All aneurysms were located in the distal circulation, primarily in the anterior circulation system. Glue embolization was successfully performed in all cases, achieving complete aneurysm sac and parent vessel obliteration. Follow-up at 3 months indicated mRS scores of 0 or 1 in 96.5% of cases. Six-month angiographic follow-up showed no aneurysm regrowth or new formations.

CONCLUSION

Endovascular glue embolization demonstrated high efficacy and safety in treating ruptured IMAs, with a 100% obliteration rate and favorable clinical outcomes in this single-center experience. Despite limitations such as its retrospective design and small sample size, the study supports glue embolization as a viable, less invasive alternative to traditional surgery. Further comparative studies are needed to confirm these findings and refine treatment approaches.

Endovascular treatment of mycotic aneurysms: An update meta-analysis

INTRODUCTION

Intracranial mycotic or infectious aneurysms result from the infection of arterial walls, most caused by bacterial or fungal organisms. These infections can weaken the arterial wall, leading to the formation of an aneurysm, a localized dilation, or a bulge. The management can be conservative mainly based on antibiotics or invasive methods such as clipping or endovascular treatment.

PURPOSE

We performed a systematic review and meta-analysis of the current literature on endovascular treatment of mycotic aneurysms, analyzing the safety and efficacy associated with this procedure.

METHODS

We systematically searched on PUBMED, Cochrane Library, Embase, and Web of Science databases. Our search strategy was carefully crafted to conduct a thorough investigation of the topic, utilizing a comprehensive combination of relevant keywords. This meta-analysis included all studies that reported endovascular treatment of mycotic aneurysms. To minimize the risk of bias, studies with fewer than four patients, studies where the main outcome was not found, and studies with no clear differentiation between microsurgical and endovascular treatment were excluded.

RESULTS

In a comprehensive analysis of 134 patients, it was observed that all except one patient received antibiotics as part of their treatment. Among the patients, 56% (a total of 51 out of 90 patients) underwent cardiac surgery. Additionally, three patients required a craniotomy following endovascular treatment. 12 patients experienced morbidity related to the procedures performed, indicating complications arising from the interventions. Furthermore, four aneurysms experienced rebleeding while treatment. A pooled analysis of the endovascular treatment of the mycotic aneurysm revealed a good level of technical success, achieving a 100% success rate in 12 out of 14 studies (97-100%; CI 95%; I2 = 0%), as illustrated in Fig. 2. Similarly, the aneurysm occlusion rate demonstrated a notable efficacy, with a success rate of 97% observed in 12 out of 14 studies (97-100%; CI 95%; I2 = 0%), as depicted in Fig. 3.

CONCLUSION

The results strongly support the efficacy of endovascular treatment in achieving technical success, complete aneurysm occlusion, and favorable neurological outcomes. Additionally, the notably low incidence of complications and procedure-related mortality reaffirms the safety and benefits associated with this intervention.

A case of infectious intracranial aneurysm that formed and ruptured within a few days after occlusion of the proximal middle cerebral artery by infective endocarditis

Background

Embolic cerebral infarction and infectious intracranial aneurysms (IIAs) are well-known central nervous system complications of infective endocarditis (IE). In this report, we describe a rare case of cerebral infarction caused by the occlusion of the M2 inferior trunk due to IE, followed by the rapid formation and rupture of IIA.

Case Description

A 66-year-old woman was admitted to the hospital with a diagnosis of IE and embolic cerebral infarction after being brought to the emergency department with a 2-day history of fever and difficulty walking. After admission, she was immediately started on antibiotic therapy. Three days later, the patient suddenly became unconscious, and a head computed tomography (CT) scan showed massive cerebral hemorrhage and subarachnoid hemorrhage. Contrast-enhanced CT showed a 13-mm large aneurysm in the left middle cerebral artery (MCA) bifurcation. An emergency craniotomy was performed, and intraoperative findings revealed a pseudoaneurysm at the origin of the M2 superior trunk. Clipping was considered difficult, so trapping and internal decompression were performed. The patient died on the 11^th day after surgery due to the worsening of her general condition. The pathology of the excised aneurysm was consistent with a pseudoaneurysm.

Conclusion

IE may cause occlusion of the proximal MCA and rapid formation and rupture of IIA. It should be noted that the location of IIA may be a short distance away from the occlusion site.

Significant increase in mortality and risk of acute ischemic stroke in infective endocarditis patients with subarachnoid hemorrhage secondary to mycotic aneurysms

Infective Endocarditis (IE) patients are known to have a variety of complications with one of the rarest, but serious being cerebral mycotic aneurysm, which can result in subarachnoid hemorrhage (SAH). Using the National In-Patient Sample database, we sought to determine the rate of acute ischemic stroke (AIS) and outcomes in IE- patients with and without SAH. In total, we identified 82,844 IE-patients from 2010 to 2016, of which 641 had a concurrent diagnosis of SAH. IE patients with SAH had a more complicated course, higher mortality rate (OR 4.65 CI 95% 3.9-5.5, P < 0.001), and worse outcomes. This patient population also had a significantly higher rate of AIS (OR 6.3 CI 95% 5.4-7.4, P < 0.001). Overall, 41.5% of IE-patients with SAH had AIS during their hospitalization as compared to 10.1% of IE only patients. IE-patients with SAH were more likely to undergo endovascular treatment (3.6%) with 0.8% of the IE patients with AIS undergoing mechanical thrombectomy. While IE-patients are at risk for various complications, our study suggests a significant increase in the mortality and risk of AIS in those with SAH.

Case report: Meningitis and intracranial aneurysm caused by mixed infection of oral microflora dominated by anaerobes

Introduction

Meningitis caused by oral anaerobic bacteria is rare, especially when complicated with an infected intracranial aneurysm. This paper has described an extremely rare case of bacterial meningitis caused by a mixed infection of oral microflora dominated by anaerobes, which developed cerebral infarcts, brain abscess, intracranial aneurysm, and severe hydrocephalus during treatment.

Case report

We describe a 65-year-old male patient who was presented with fever and headache as the initial symptoms and then developed left ophthalmoplegia, right hemiplegia, and disturbance of consciousness. Brain imaging showed that intracranial lesions were increased progressively, and cerebral infarcts, brain abscesses, intracranial aneurysm, and severe hydrocephalus were appeared gradually. Eventually, we diagnosed it as anaerobic meningitis by making deoxyribonucleic acid sequencing from the brain abscess pus. After using an anti-microbial regimen that can sufficiently cover anaerobes, the patient's condition was effectively controlled.

Conclusion

Anaerobic meningitis can cause a series of intracranial complications. Among them, the intracranial aneurysm is extremely rare. When evidence shows that the infection originates from oral flora, physicians should consider the possibility of this type of encephalitis. An early diagnosis and timely treatment are crucial to improving the prognosis.

Ruptured intracranial infectious aneurysms: Single Canadian center experience

Background:

Ruptured intracranial infected aneurysms (IIAs) are relatively rare, but they portend high mortality. To the best of our knowledge, there is no Canadian case series on IIA, as well there is a relative paucity of international published experiences. Our purpose is to share the experience of a single Canadian tertiary center in managing ruptured IIA and to conduct a systematic review.

Methods:

We did a retrospective case review series of adult patients with ruptured IIA treated at our institution. Second, we conducted a systematic review of the literature on ruptured IIA between 2011 and 2021 inclusive.

Results:

At our institution, of a total eight cases with ruptured IIA, four were treated endovascularly and two by surgical bypass. For the systematic review, we included nine noncomparative studies with a total of 509 patients (318 males) and at least 437 ruptured IIA aneurysms. Favorable outcome was specified for 63.3% of patients (n = 57). Regarding ruptured IIA, favorable clinical outcome was described in 59.3% (n = 16).

Conclusion:

This study highlights a single Canadian tertiary center experience in the management of IIA and compares it to the global trends of the past 10 years in a systematic review.

Endovascular therapy for intracranial infectious aneurysms associated with a left ventricular assist device: illustrative case

BACKGROUND

Cerebrovascular events and infection are among the most common complications of left ventricular assist device (LVAD) therapy. The authors reported on a patient with an infectious intracranial aneurysm (IIA) associated with LVAD infection that was successfully occluded by endovascular therapy.

OBSERVATIONS

A 37-year-old man with severe heart failure received an implantable LVAD. He was diagnosed with candidemia due to driveline infection 44 months after LVAD implantation, and empirical antibiotic therapy was started. After 4 days of antibiotic treatment, the patient experienced sudden dizziness. Computed tomography (CT) revealed subarachnoid hemorrhage in the right frontal lobe, and CT angiography revealed multiple aneurysms in the peripheral lesion of the anterior cerebral artery (ACA) and middle cerebral artery. Two weeks and 4 days after the first bleeding, aneurysms on the ACA reruptured. Each aneurysm was treated with endovascular embolization using n-butyl cyanoacrylate. Subsequently, the patient had no rebleeding of IIAs. The LVAD was replaced, and bloodstream infection was controlled. He received a heart transplant and was independent 2 years after the heart transplant.

LESSONS

LVAD-associated IIAs have high mortality and an increased risk of surgical complications. However, endovascular obliteration may be safe and thus improve prognosis.

Simultaneous intracerebral and subarachnoid hemorrhages caused by multiple infectious intracranial aneurysms treated endovascularly and by microsurgical clipping: illustrative case

BACKGROUND

Infected intracranial aneurysms are relatively rare but tend to occur in multiple locations. Establishing an optimal treatment strategy for multiple ruptured aneurysms is often challenging, especially when simultaneous ruptures occur in different locations. We report a case of simultaneous intracerebral and subarachnoid hemorrhages caused by the rupture of multiple infected intracranial aneurysms.

OBSERVATIONS

A 23-year-old male with a 2-week history of chronic fever presented with sudden onset of severe headache and visual disturbance. Computed tomography showed intracerebral hemorrhage in the right occipital lobe and subarachnoid hemorrhage in the area of the left Sylvian fissure. Further investigation documented Staphylococcus bacteremia, verrucae on the mitral valve, and aneurysms arising from the right posterior cerebral artery (PCA) and the left middle cerebral artery (MCA). A larger aneurysm arising from the PCA was successfully occluded endovascularly, but subsequent endovascular occlusion of the MCA aneurysm was unsuccessful because some important branches were observed extending from the aneurysm. The left MCA aneurysm was then obliterated by angioplastic clipping via left pterional craniotomy. The patient showed a favorable neurological recovery after treatment.

LESSONS

In such complex cases of infectious aneurysms, the method and timing of treatment need to be carefully determined based on the medical condition.

Safety Profile and Factors Associated With Good Outcome for Endovascularly Treated Infectious Intracranial Aneurysms

BACKGROUND

Infectious intracranial aneurysms (IIAs), or mycotic aneurysms, are infectious inflammatory lesions that can cause devastating neurological damage or death. Recent systemic reviews have suggested endovascular treatment to be efficacious for IIA management.

OBJECTIVE

To compare the safety profile of different endovascular methods for treating ruptured and unruptured IIAs and factors associated with good clinical and radiographic outcomes.

METHODS

We conducted a retrospective single study of endovascularly treated ruptured and unruptured IIAs between 2003 and 2019. Univariate and multivariate analyses were used to study patient presentation, endovascular treatments used, and clinical and radiographic outcomes.

RESULTS

Thirty-eight patients with ruptured (n = 20) and unruptured (n = 18) IIAs treated with endovascular methods were included. One patient required retreatment after aneurysm recanalization, and 2 patients demonstrated new infarcts after embolization. There was no postprocedural radiographic hemorrhage or infarct and no difference in clinical and radiographic outcomes comparing treatment modality. Hypertension was associated with ruptured IIA status and worse clinical outcome at 6 mo (odds ratio: 0.03 [95% confidence interval: 0.002-0.52]).

CONCLUSION

In this study, the largest single-center series to date, we showed that endovascular intervention is a safe and effective strategy for both ruptured and unruptured IIAs. Hypertension was associated with ruptured status and worse clinical outcome. Procedures are generally well-tolerated and safe, with good outcomes for patients.

Endovascular treatment of infectious intracranial aneurysms complicating infective endocarditis: a series of 31 patients with 55 aneurysms

PURPOSE

Endovascular treatment (EVT) has become a major option in management of infectious intracranial aneurysms (IIAs) complicating infective endocarditis. We report a retrospective, single-center series of consecutive patients with IIAs treated by EVT.

METHODS

Patients were included from January 2009 to July 2020. IIAs were diagnosed on DSA. Each patient underwent a neurological assessment before and after EVT and was followed up by imaging within 15 days of EVT. Safety was assessed on the evolution of NIHSS score. A minor stroke was defined as a worsening of NIHSS < 4 points. Efficacy was defined as the absence of hemorrhagic event during cardiac surgery and the exclusion of the IIA on control imaging.

RESULTS

Sixty-two IIAs (30 ruptured) were diagnosed in 31 patients. Fifty-six IIAs were diagnosed on the first DSA and 6 on the early control exploration. EVT was achieved in 55 IIAs by parent artery occlusion with glue in 52 distal IIAs and coils in 3 proximal IIAs. IIAs were located in 90.9% of cases on a fourth-division branch of a cerebral artery. The neurological examination remained unchanged in 29 patients (93.5%), and 2 patients suffered minor stroke. EVT was performed before cardiac surgery in 20/22 patients. All treated IIAs were excluded on follow-up imaging. No hemorrhage was observed during cardiac surgery or in the aftermath. Seven (11.3%) unruptured IIAs were not embolized.

CONCLUSION

EVT of IIAs by occlusion of the parent artery is effective in preventing rupture and carries no significant neurological risk.

Erratum to Evaluating the safety and efficacy of various endovascular approaches for the treatment of infectious intracranial aneurysms: a systematic review. World Neurosurgery. Volume 144, December 2020, Pages 293-298.e15

OBJECTIVE

A review of endovascular cerebral mycotic aneurysm treatment with Onyx liquid embolic, N-butyl-2-cyanoacrylate (NBCA), or coil embolization has not been reported. The authors conduct a systematic review on endovascular treatment methods of mycotic aneurysms.

METHODS

A systematic literature review was performed using the PubMed and MEDLINE databases for studies published between 1986 and 2020. All studies assessing outcomes related to endovascular Onyx embolization, NBCA embolization, or coiling were included.

RESULTS

A total of 74 studies were ultimately selected, including 180 (67% male) patients comprising 243 aneurysms treated endovascularly. The mean age was 38.2 ± 17.6 years, and the most common symptom on presentation was headache (31%). Most aneurysms were located on the middle cerebral artery (52.5%), and over half presented with rupture (53.8%). Coiling was the most commonly employed technique (50.4%), and obliteration rates were comparable across coiling, NBCA, and Onyx (99.1%, 100%, 100%, respectively). Complication rates were also comparable (4.3% vs. 15.2% vs. 8.1%).

CONCLUSION

Embolization for infectious intracranial aneurysm appears to be an effective treatment option for mycotic aneurysms. Embolization rates were comparable between coiling, NBCA, and Onyx embolization. Noninferiority among these modalities cannot be demonstrated given the retrospective nature of this review, evolution of endovascular techniques over the years, and changes in treatment paradigms in the last 2 decades. Ideally, further prospective research will be needed to find which treatment method offers the lowest complication rates and the best outcomes for patients with mycotic aneurysms.

Evaluating the Safety and Efficacy of Various Endovascular Approaches for Treatment of Infectious Intracranial Aneurysms: A Systematic Review

OBJECTIVE

A review of endovascular cerebral mycotic aneurysm treatment with Onyx liquid embolic, N-butyl-2-cyanoacrylate (NBCA), or coil embolization has not been reported. The authors conduct a systematic review on endovascular treatment methods of mycotic aneurysms.

METHODS

A systematic literature review was performed using the PubMed and MEDLINE databases for studies published between 1986 and 2020. All studies assessing outcomes related to endovascular Onyx embolization, NBCA embolization, or coiling were included.

RESULTS

A total of 73 studies were ultimately selected including 180 (67% male) patients comprising 243 aneurysms treated endovascularly. The mean age was 38.2 ± 17.6 years, and the most common symptom on presentation was headache (31%). Most aneurysms were located on the middle cerebral artery (52.5%), and over half presented with rupture (53.8%). Coiling was the most commonly employed technique (50.4%), and obliteration rates were comparable across coiling, NBCA, and Onyx (99.1%, 100%, 100%, respectively). Complication rates were also comparable (4.3% vs. 15.2% vs. 8.1%).

CONCLUSIONS

Embolization for infectious intracranial aneurysm appears to be an effective treatment option for mycotic aneurysms. Embolization rates were comparable among coiling, NBCA, and Onyx embolization. Noninferiority among these modalities cannot be demonstrated given the retrospective nature of this review, evolution of endovascular techniques over the years, and changes in treatment paradigms in the past 2 decades. Ideally, further prospective research will be necessary to find which treatment method offers the lowest complication rates and the best outcomes for patients with mycotic aneurysms.

MCA-to-MCA Bypass with Interposition Graft for Ruptured Mycotic Middle Cerebral Artery Aneurysm

Mycotic aneurysm, also referred to as infected aneurysm, is a rare entity that may result from the bacterial infection or infective endocarditis.^1-3 The treatment options include conservative medication and endovascular or direct microsurgical intervention.^1,4,5 However, the optimal strategy remains unknown and cerebral revascularization may be required in some rare cases.⁶ In this surgical video, we demonstrate a distal middle cerebral artery (MCA) mycotic aneurysm that we treated by intracranial-intracranial bypass with an interpositional graft. Our patient is a 53-year-old male who presented with a 6-day history of severe headache. He was subsequently admitted to our institution. Preoperative computed tomography angiography showed a left temporal hematoma (>30 mL) and an opercular segment of the MCA (M3) aneurysm, which was highly suspicious for mycotic origin. A standard frontotemporal craniotomy was carried out with preservation of superficial temporal artery (STA). Following the sylvian fissure dissection, the aneurysm was exposed with the characteristics of a thick wall and an undefinable neck, which made direct clip application difficult. The aneurysm was resected initially, and 2 cut ends were reconnected by an STA graft. Following arterial reconstruction, intraoperative Doppler revealed a patent status of the interpositional graft vessel. Postoperatively, no neurologic deficit was observed and computed tomography angiography demonstrated total elimination of the aneurysm without stenosis of the graft vessel. Low-molecular dextran was prescribed rather than aspirin, as there was concern for hemorrhage. Antibiotic treatment was used for at least 4 weeks, and the patient was transferred to the inpatient cardiology team for management of endocarditis. A 4-month follow-up angiogram showed a patent STA and excellent left distal MCA blood flow (Video 1). The favorable outcome of this case revealed that MCA-to-MCA bypass with interpositional graft is a safe, effective method for the unclippable cerebral aneurysm. As other authors have asserted, a full dose of long-term antibiotic therapy remains essential following intervention.⁷ Meanwhile, dextran has proved to be a viable alternative for anticoagulation during perioperative management of bypass surgery.^8,9.

Infectious intracranial aneurysms: a systematic review of epidemiology, management, and outcomes

Infectious intracranial aneurysms (IIAs) are a rare cerebrovascular complication of systemic infections induced by microbial infiltration and degradation of the arterial vessel wall. Studies on the epidemiology and management of IIAs are limited to case reports and retrospective single-center studies, and report a large variability in epidemiological features, management, and outcomes due to the limited sample size. We conducted a systematic review of all published papers on IIAs in the English literature using MEDLINE and SCOPUS database from January 1950 to June 2017. A total of 288 publications describing 1191 patients with IIA (1398 aneurysms) were included and reviewed for epidemiological features, disease features, treatment and outcome. All patients were merged into a single cohort and summary data are presented. The majority of reported IIAs are distally located, relatively small (<5 mm), involve the anterior circulation, are associated with a relatively high rate of rupture, and demonstrate a propensity to multiplicity of aneurysms. Sensitive diagnosis of IIAs requires digital subtraction angiography and not CT angiography or MR angiography. Treatment of ruptured, symptomatic, or enlarging IIAs has evolved over the last 50 years. Endovascular therapy is associated with a high success rate and low morbidity compared with microsurgical and medical management. A treatment algorithm for the management of patients with IIA in various contexts is proposed and the need for prospective multicenter studies is emphasized.

Surgical Management of Infective Endocarditis Complicated by Embolic Stroke: Practical Recommendations for Clinicians

There has been an overall improvement in surgical mortality for patients with infective endocarditis (IE), presumably because of improved diagnosis and management, centered around a more aggressive early surgical approach. Surgery is currently performed in approximately half of all cases of IE. Improved survival in surgery-treated patients is correlated with a reduction in heart failure and the prevention of embolic sequelae. It is reported that between 20% and 40% of patients with IE present with stroke or other neurological conditions. It is for these IE patients that the timing of surgical intervention remains a point of considerable discussion and debate. Despite evidence of improved survival in IE patients with earlier surgical treatment, a significant proportion of patients with IE and preexisting neurological complications either undergo delayed surgery or do not have surgery at all, even when surgery is indicated and guideline endorsed. Physicians and surgeons are caught in a common conundrum where the urgency of the heart operation must be balanced against the real or perceived risks of neurological exacerbation. Recent data suggest that the risk of neurological exacerbation may be lower than previously believed. Current guidelines reflect a shift toward early surgery for such patients, but there continue to be important areas of clinical equipoise. Individualized clinical assessment is of major importance for decision making, and, as such, we emphasize the need for the functioning of an endocarditis team, including cardiac surgeons, cardiologists, infectious diseases specialists, neurologists, neurosurgeons, and interventional neuroradiologists. Here, we present 2 illustrative cases, critically review contemporary data, and offer conceptual and practical suggestions for clinicians to address this important, common, and often fatal cardiac condition.