Intracranial Aneurysms in Adult Moyamoya Disease

Rupture of a flow aneurysm secondary to spontaneous extracranial to intracranial revascularisation in the posterior fossa following radiation-induced vasculopathy for cerebellar tumour

Paediatric patients receiving cranial irradiation therapy for brain tumours are at increased risk of cerebrovascular complications. Radiation-induced moyamoya syndrome (MMS) is a well-recognised complication of this. We present a case of an 8-year-old boy with a history of medulloblastoma, who underwent surgical excision followed by post-operative adjuvant oncological treatment. Six years later, he developed cerebellar/intraventricular haemorrhage. He underwent an emergency external ventricular drain (EVD) insertion followed by posterior fossa suboccipital craniotomy. On dural opening, an abnormal vessel was visualised on the surface of the right cerebellar hemisphere, which was not disturbed. No obvious abnormalities were identified intra-operatively. Cerebral catheter angiography confirmed the presence of a right-sided occipital artery (OA) to posterior inferior cerebellar artery (PICA) extracranial to intracranial (EC-IC) bypass with a zone of the distal PICA territory supplied by this EC-IC bypass. A presumed flow aneurysm originated from the bypass in the distal PICA, identified as cause for the haemorrhage. We highlight a rare cause for intracranial haemorrhage in this cohort of patients. Children who have undergone radiotherapy may have exquisitely sensitive cerebral vasculature and need careful vigilance and evaluation for vasculopathic complications following spontaneous haemorrhage.

Classification and treatment strategy for Moyamoya disease-related aneurysms

BACKGROUND

Moyamoya disease (MMD) is a cerebrovascular disorder characterized by progressive unilateral or bilateral stenosis of the distal internal carotid artery. As hemodynamic features in MMD patients alter, the comorbidity of intracranial aneurysm (IA) is sometimes observed clinically. We aim to investigate clinical characteristics and therapeutic strategies for the comorbidity of Moyamoya disease with intracranial aneurysms (MMD-IA).

METHODS

A total of 13 MMD-IA patients were recruited in this study and were manifested to be intracranial hemorrhage. We reviewed the surgical technique notes for all patients.

RESULTS

According to the locations of an aneurysm, MMD-IA could be divided into several categories: (1) MMD-IA at a circle of Willis-aneurysms usually located at the trunk of Willis circle; (2) MMD-IA at collateral anastomosis-aneurysms located at the distal end of collateral anastomosis; and (3) MMA-IA at basal ganglia region. In this report, aneurysms in 10 patients located at Willis circle, 2 at the pericallosal artery, and 1 at the basal ganglia region. Among them, endovascular embolism was performed among 5 patients. Aneurysm clipping was conducted among 7 patients. A patient with an aneurysm at the basal ganglia region just accepted revascularization treatment. All the treatments were successful. Follow-up studies, ranging from 6 to 24 months, demonstrated all patients received satisfactory curative effects.

CONCLUSION

Diverse clinical presentations could be observed among MMD-IA patients. Individualized neurosurgical treatments should be chosen according to the locations of the aneurysm.

Role of human dural fibroblasts in the angiogenic responses of human endothelial cells: An in vitro dural model and the application of lab-on-a-chip for EDAS

Encephaloduroarteriosynangiosis (EDAS), an indirect anastomosis procedure, is widely accepted as a primary treatment for moyamoya disease (MMD) to improve collateral blood flow. During surgical intervention, dural fibroblasts (DuF) are thought to produce various proteins that create an angiogenic microenvironment. However, the biophysiological evidence supporting the angiogenic properties of this surgical technique has not been thoroughly elucidated. The purpose of these studies was to determine whether DuF releases pro-angiogenic factors and chemokines and promotes angiogenic properties in human endothelial cells (ECs) under IL-1β-mediated wound conditions, which are expected to occur during the process of neo-vascularization within the dura mater. Furthermore, a microfluidic chemotaxis platform was implemented to investigate the angiogenic activity of ECs in response to a reconstituted dura model. Transcriptome sequencing revealed that IL-1β stimulation on DuF induced a significant upregulation of various pro-angiogenic genes, including IL-6, IL-8, CCL-2, CCL-5, SMOC-1, and SCG-2 (p < 0.05). Moreover, compared to ECs cultured in naïve media or naïve DuF media, those exposed to IL-1β-DuF conditioned media expressed higher mRNA and protein levels of these pro-angiogenic factors (p < 0.001). ECs co-cultured with IL-1β-DuF also exhibited considerable migration on the microfluidic chemotaxis platform. Furthermore, the chemotactic effects on the ECs were reduced upon neutralization of IL-8 or inhibition of NF-κB signaling. Our findings demonstrate that IL-1β-DuFs release factors that activate and enhance the angiogenic properties of ECs. These results suggest a potential interaction between DuF and ECs following EDAS for MMD, and these components could be targeted for the development of therapeutic biomarkers.

Treatment of moyamoya disease with intracranial aneurysm by surgical clipping combined with encephalo-duro-myo-synangiosis surgery: a case report and literature review

BACKGROUND

We report a case of 39-year-old male patient with an unruptured middle cerebral artery aneurysm associated with moyamoya disease (MMD) treated by surgical clipping combined with encephalo-duro-myo-synangiosis surgery.

CASE DESCRIPTION

A 39-year-old male patient with a history of intraventricular hemorrhage was admitted to our hospital. Preoperative digital subtraction angiography (DSA) showed the aneurysm, arising from a collateral branch of the right middle cerebral artery (RMCA), had an extremely thin neck. Also present were an occlusion of the RMCA main trunk, and moyamoya vessels. Microsurgical aneurysm clipping was performed for the aneurysm, while encephalo-duro-myo-synangiosis was performed for ipsilateral MMD. At the 4-month follow-up, the patient had recovered well and DSA indicated improved cerebral perfusion with no de novo aneurysms.

CONCLUSIONS

For ipsilateral moyamoya disease accompanied with intracranial aneurysm (IA), simultaneous surgery combining microsurgical clipping and encephalo-duro-myo-synangiosis can be a good treatment option.

Advances in Management of the Stroke Etiology One-Percenters

PURPOSE OF REVIEW

Uncommon causes of stroke merit specific attention; when clinicians have less common etiologies of stoke in mind, the diagnosis may come more easily. This is key, as optimal management will in many cases differs significantly from "standard" care.

RECENT FINDINGS

Randomized controlled trials (RCT) on the best medical therapy in the treatment of cervical artery dissection (CeAD) have demonstrated low rates of ischemia with both antiplatelet and vitamin K antagonism. RCT evidence supports the use of anticoagulation with vitamin K antagonism in "high-risk" patients with antiphospholipid antibody syndrome (APLAS), and there is new evidence supporting the utilization of direct oral anticoagulation in malignancy-associated thrombosis. Migraine with aura has been more conclusively linked not only with increased risk of ischemic and hemorrhagic stroke, but also with cardiovascular mortality. Recent literature has surprisingly not provided support the utilization of L-arginine in the treatment of patients with mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS); however, there is evidence at this time that support use of enzyme replacement in patients with Fabry disease. Additional triggers for reversible cerebral vasoconstriction syndrome (RCVS) have been identified, such as capsaicin. Imaging of cerebral blood vessel walls utilizing contrast-enhanced MRA is an emerging modality that may ultimately prove to be very useful in the evaluation of patients with uncommon causes of stroke. A plethora of associations between cerebrovascular disease and COVID-19 have been described. Where pertinent, authors provide additional tips and guidance. Less commonly encountered conditions with updates in diagnosis, and management along with clinical tips are reviewed.

Natural course and risk factors of moyamoya disease with unruptured intracranial aneurysm

Background and objective

The natural course and risk factors of moyamoya disease (MMD) associated with unruptured intracranial aneurysms involving stenosed parental arteries are scarcely studied. This study aimed to elucidate the natural course of MMD and its associated risk factors in patients with MMD with unruptured aneurysms.

Methods

Between September 2006 and October 2021, patients with MMD with intracranial aneurysms at our center were examined. The natural course, clinical features, radiological features, and follow-up outcomes after revascularization were analyzed.

Results

This study included 42 patients with MMD with intracranial aneurysms (42 aneurysms). The age distribution of MMD cases ranged from 6 to 69 years, with four children (9.5%) and 38 adults (90.5%). A total of 17 male and 25 female subjects were included (male-to-female ratio: 1:1.47). The first symptom was cerebral ischemia in 28 cases, and cerebral hemorrhage occurred in 14 cases. There were 35 trunk aneurysms and seven peripheral aneurysms. There were 34 small aneurysms (<5 mm) and eight medium aneurysms (5-15 mm). During the average clinical follow-up period of 37.90 ± 32.53 months, there was no rupture or bleeding from aneurysms. Twenty-seven of these patients underwent a cerebral angiography review, in which it was found that one aneurysm had enlarged, 16 had remained unchanged, and 10 had shrunk or disappeared. A correlation exists between the reduction or disappearance of aneurysms and the progression of the Suzuki stages of MMD (P = 0.015). Nineteen patients underwent EDAS on the aneurysm side, and nine aneurysms disappeared, while eight patients did not undergo EDAS on the aneurysm side and one aneurysm disappeared.

Conclusion

The risk of rupture and hemorrhage of unruptured intracranial aneurysms is low when the parent artery already has stenotic lesions, thus, direct intervention may not be necessary for such aneurysms. The progression of the Suzuki stage of moyamoya disease may play a role in the shrinkage or disappearance of the aneurysms, thereby decreasing the risk of rupture and hemorrhage. Encephaloduroarteriosynangiosis (EDAS) surgery may also help promote atrophy or even the disappearance of the aneurysm, thus reducing the risk of further rupture and bleeding.

Parent artery occlusion for ruptured aneurysms in moyamoya vessels or on collaterals

Background

Aneurysms in moyamoya vessels or on collaterals are difficult to treat. Parent artery occlusion (PAO) via endovascular treatment (EVT) is often the last resort, but the safety and efficacy of this approach need to be evaluated.

Materials and methods

A retrospective study was performed on patients admitted to our hospital who were diagnosed with unilateral or bilateral moyamoya disease (MMD) associated with ruptured aneurysms in moyamoya vessels or on collaterals. These aneurysms were treated with PAO, and the clinical outcome was recorded.

Results

Eleven patients were aged 54.7 ± 10.4 years, and six patients were male (54.5%, 6/11). The aneurysms in 11 patients were single and ruptured, and the average size was 2.7 ± 0.6 mm. Three (27.3%, 3/11) aneurysms were located at the distal anterior choroidal artery, 3 (27.3%, 3/11) were at the distal lenticulostriate artery, 3 (27.3%, 3/11) were at the P2-3 segment of the posterior cerebral artery, 1 (9.1%, 1/11) was at the P4-5 segment of the posterior cerebral artery, and 1 was at the transdural location of the middle meningeal artery. Among the 11 aneurysms, PAO by coiling was performed on 7 (63.6%, 7/11), and Onyx casting was performed on 4 (36.4%, 4/11). Of 11 patients, 2 (18.2%, 2/11) suffered intraoperative hemorrhagic complications. During follow-up, all patients had good outcomes with a modified Rankin scale score of 0-2.

Conclusion

As a last resort, the application of PAO with coiling or casting Onyx for ruptured aneurysms in moyamoya vessels or on collaterals may be safe with an acceptable clinical outcome. However, patients with MMD may not always achieve expected health outcomes, and PAO for the aneurysm can bring only temporary relief.

Digital subtraction angiography in cerebrovascular disease: current practice and perspectives on diagnosis, acute treatment and prognosis

Digital Subtraction Angiography (DSA) is the gold-standard imaging modality in acute cerebrovascular diagnosis. The role of DSA has become increasingly prominent since the incorporation of endovascular therapy in standards of care for acute ischemic stroke. It is used in the assessment of cerebral vessel patency; however, the therapeutic role of DSA from a prognostic standpoint merits further investigation. The current paper provides an update on current practice on diagnostic, therapeutic and prognostic use of DSA in acute cerebrovascular diseases and various indications and perspectives that may apply, or limit its use, in ongoing surveillance or prognosis. Pre-clinical and clinical studies on the aspects, including but not limited to the morphology of cerebrovasculature in acute ischaemic stroke, are required to delineate and inform its prognostic role.

Endovascular Treatment of Posterior Cerebral Artery Trunk Aneurysm: The Status Quo and Dilemma

The posterior cerebral artery (PCA) is an important artery that can be divided into four segments (P1-4): segments P1-2 are proximal segments, and segments P3-4 are distal segments. Various aneurysms can occur along the PCA trunk. True saccular aneurysms are rare, and most PCA trunk aneurysms are dissecting. Sometimes, the PCA trunk can give rise to flow-related aneurysms in association with high-flow arteriovenous shunt diseases or moyamoya disease and internal carotid artery occlusion. Some PCA trunk aneurysms require treatment, especially ruptured or large/giant aneurysms. Recently, endovascular treatment (EVT) has become the mainstream treatment for PCA trunk aneurysms, and it mainly involves reconstructive or deconstructive techniques. Traditional EVT includes selective coiling with/without stent or balloon assistance and parent artery occlusion (PAO). For proximal aneurysms, the PCA should be preserved. For distal aneurysms, PAO can be performed. However, during EVT, preservation of the PCA must naturally be the prime objective. Recently, flow-diverting stents have been used and are a revolutionary treatment for unruptured dissecting aneurysms of the PCA trunk. Despite the associated complications, EVT remains an effective method for treating PCA trunk aneurysms and can result in a good prognosis.

ACR Appropriateness Criteria® Cerebrovascular Diseases-Aneurysm, Vascular Malformation, and Subarachnoid Hemorrhage

Cerebrovascular disease is a broad topic. This document focuses on the imaging recommendations for the varied clinical scenarios involving intracranial aneurysms, vascular malformations, and vasculitis, which all carry high risk of morbidity and mortality. Additional imaging recommendations regarding complications of these conditions, including subarachnoid hemorrhage and vasospasm, are also covered. While each variant presentation has unique imaging recommendations, the major focus of this document is neurovascular imaging techniques. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Successful shrinkage of anterior communicating artery aneurysm after ACA–ACA bypass with interposed occipital artery graft in pediatric moyamoya disease: illustrative case

BACKGROUND

Selecting therapeutic options for moyamoya disease (MMD)-associated anterior communicating artery (ACoA) aneurysm, a rare pathology in children, is challenging because its natural course remains unclear.

OBSERVATIONS

A 4-year-old boy exhibiting transient ischemic attacks was diagnosed with unilateral MMD accompanied by an unruptured ACoA aneurysm. Although superficial temporal artery to middle cerebral artery anastomosis eliminated his symptoms, the aneurysm continued to grow after surgery. Since a previous craniotomy and narrow endovascular access at the ACoA precluded both aneurysmal clipping and coil embolization, the patient underwent a surgical anastomosis incorporating an occipital artery graft between the bilateral cortical anterior cerebral arteries (ACAs). This was intended to augment blood flow in the ipsilateral ACA territory and to reduce the hemodynamic burden on the ACoA complex. The postoperative course was uneventful, and radiological images obtained 12 months after surgery revealed good patency of the bypass and marked shrinkage of the aneurysm in spite of the intact contralateral internal carotid artery.

LESSONS

Various clinical scenarios should be assessed carefully with regard to this pathology. Bypass surgery aimed at reducing flow to the aneurysm might be an alternative therapeutic option when neither coiling nor clipping is feasible.

Treatment of ruptured aneurysms of the choroidal collateral system in moyamoya disease: a systematic review and data analysis

OBJECTIVE

Moyamoya disease (MMD) is a chronic, progressive steno-occlusive condition of the distal internal carotid arteries of unknown etiology. Collateral arterial networks typically develop in MMD, bypassing the steno-occlusion. Aneurysms arising on the collateral networks are a known source of hemorrhage. The choroidal collateral system is the most common location for collateral pathway aneurysms in MMD and associated hemorrhage. The authors performed data collection and analysis to further elucidate the best treatment approaches for ruptured aneurysms of the choroidal collateral system in MMD, which as yet remain unclear.

METHODS

A comprehensive data collection and analysis of case reports and case series with ruptured choroidal collateral artery aneurysms (CCAAs) was performed. PRISMA guidelines for systematic reviews were followed and the Medline, Embase, and Scopus databases were searched for relevant studies. A database was created including patients with ruptured CCAA in MMD. Original data from case series were included whenever possible. A previously unreported case of a ruptured choroidal artery aneurysm in MMD treated by the authors was also included.

RESULTS

The database comprised 72 patients with ruptured CCAA in MMD. The most common clinical symptoms were headache, nausea, and vomiting (39%). Initially, a conservative treatment approach was chosen in 29% of cases but led to rehemorrhage in 40% of cases; 63% of these rehemorrhages occurred during the first 35 days. Endovascular treatment seemed a safe option for aneurysm exclusion, mainly through parent vessel sacrifice, but had a treatment failure rate of 21%, due to inadequate access. Aneurysm treatment with revascularization as the initial treatment strategy led to aneurysm regression in 82% with no reported rehemorrhage. Aneurysm exclusion through open surgery was effective but was associated with a relatively high complication rate (25%). Outcome after rupture of CCAA was poor, with 41% of patients deceased or permanently disabled. Overall, patient outcomes were better in the endovascular and revascularization treatment group than in the conservative treatment group.

CONCLUSIONS

Rupture of CCAA in MMD is associated with high morbidity and rerupture rate requiring urgent treatment.

Clinical and Hemodynamic Features in Moyamoya Disease with Intracranial Aneurysms

OBJECTIVE

Intracranial aneurysms (IAs) are occasionally associated with moyamoya disease (MMD). The purpose of this study was to elucidate differences between patients with MMD with and without IAs and differences between patients with IAs at different locations.

METHODS

Between May 2012 and December 2017, consecutive patients with MMD were enrolled in a retrospective single-center study. IAs were classified as circle of Willis (CoW) or peripheral aneurysms according to the anatomic location. Clinical characteristics and hemodynamic parameters were collected and analyzed. A hemispheric analysis was performed for Suzuki stage and computed tomography perfusion parameters.

RESULTS

The study included 31 patients with MMD with IAs and 279 patients with MMD without IAs. The patients with IAs had more severe neurological dysfunction, more advanced Suzuki stage, and less hemodynamic dysfunction than the patients without IAs (P < 0.05). Of patients with MMD with IAs, 17 had CoW aneurysms, and 13 had peripheral aneurysms. Patients with CoW aneurysms were older and had more advanced Suzuki stage than patients with peripheral aneurysms (P < 0.05).

CONCLUSIONS

Patients with MMD with IAs had different clinical and hemodynamic features compared with patients with MMD without IAs. CoW aneurysms and peripheral aneurysms may occur at different stages of MMD, which may explain their differences in anatomical location, type of hemorrhage, and treatment strategy.

Clinical Features and Outcomes of Intracranial Aneurysm Associated with Moyamoya Disease

Background and Purpose

Moyamoya disease (MMD) is a rare form of intracranial stenoocclusive disease that can be associated with intracranial aneurysms. We evaluated the clinical features and outcomes of MMD-associated aneurysms while focusing on their locations.

Methods

Between January 1998 and December 2018 there were 1,302 adult and pediatric patients diagnosed as MMD at a single institution. These patients included 38 with 44 MMD-associated aneurysms. The MMD-associated aneurysms were classified into two groups based on their locations: major-artery aneurysms and non-major-artery aneurysms. The clinical and radiological data for patients with MMD-associated aneurysms were reviewed retrospectively.

Results

The 44 MMD-associated aneurysms comprised 28 in major arteries and 16 in nonmajor arteries. All of the major-artery aneurysms were initially unruptured lesions, and follow-up angiography showed that 23 (82.1%) had an improved or stable status and 5 (17.9%) had a worse status. The non-major-artery aneurysms comprised 10 ruptured and 6 unruptured lesions, and follow-up angiography showed that 11 (68.8%) had improved or were stable and 5 (31.2%) had worsened. At the latest follow-up, there were four cases of unfavorable outcome: two initial hemorrhagic insults, one treatment-related morbidity, and one repeated-hemorrhage case.

Conclusions

MMD-associated aneurysms occurred in 3.3% of the MMD cohort in this study, of which 63.6% were major-artery aneurysms and 36.4% were non-major-artery aneurysms. The major-artery group included 17.9% that became angiographically worse, while 31.2% were growing or hemorrhaging in the non-major-artery group.

Clinical features, surgical treatment, and outcome of intracranial aneurysms associated with moyamoya disease

The objective of this study was to elucidate the clinical features, surgical treatment, and outcome of intracranial aneurysms associated with moyamoya disease. We retrospectively reviewed a consecutive cohort of 79 moyamoya disease patients with 98 intracranial aneurysms at Beijing Tiantan Hospital. Clinical features, radiological findings, and outcomes were analyzed. Prevalence of intracranial aneurysms in patients with moyamoya disease was 3.9%. The mean age at diagnosis was 39.0 ± 12.4 years, with 1 peak distribution in patients from 40 to 50 years of age. The ratio of women to men was 1.00:1.03. Familial occurrence was 2.5%. The initial symptom was hemorrhage or ischemia in 56 (70.9%) and 23 patients (30.4%), respectively. Most patients presented with Suzuki stage 3 or 4. Seventy-nine cases had 98 aneurysms. Of the 98 aneurysms, sixteen aneurysms (16.3%) were treated by microsurgery and 7 by endovascular procedures, 13 aneurysms were conservatively managed, the remaining 62 were treated with revascularization alone. After a median nine-month angiographic follow-up, 18 aneurysms received clipped or embolized were completed occlusion, 18 aneurysms received conservative treated or coating were remained stable. Of the remaining 63 aneurysms that were treated with revascularization alone, 59 of 63 aneurysms remained stable, and 2 were obliterated, whereas 1 aneurysm ruptured during the follow-up. Hemorrhage was the most common symptom in intracranial aneurysms associated with moyamoya disease. Revascularization surgery may improve cerebral circulation, decreases hemodynamic stress and prevent the rupture of intracranial aneurysms.

Location-based treatment of intracranial aneurysms in moyamoya disease: a systematic review and descriptive analysis

We conducted a systematic review of the literature to evaluate the efficacy of various treatment modalities for intracranial aneurysms (IA) in patients with moyamoya disease (MMD) based on anatomical location of IA. A comprehensive review of studies documenting single cases or series of MMD patients with concomitant IA was conducted. Aneurysms were classified into two primary anatomical categories: those of the Circle of Willis (CoW) and those of peripheral "moyamoya" collateral vessels. Conservative, endovascular, and open surgical treatment modalities and their outcomes between each anatomical subgroup were descriptively compared. A total of 124 studies consisting of 275 patients with 313 IA were included. Of all IA, 59.6% were located on CoW vessels, 33.7% on peripheral vessels, and 6.7% in "other" locations. Of all CoW IA, 87.2% treated with endovascular techniques had no or minimal deficit at follow-up as compared with 56.7% of those treated with open surgery. Ninety-five percent of patients with peripheral aneurysms treated with endovascular therapy had no or minimal deficit, in contrast to open surgery (69.6%). Of peripheral IA treated conservatively with or without revascularization, 65.7% had spontaneous resolution as compared with 12.0% IA of the CoW. Our results support the use of endovascular techniques for direct treatment of both CoW and peripheral IA. Aneurysms of peripheral vessels respond well to indirect treatment through surgical revascularization as opposed to CoW aneurysms. The quality of evidence is limited due to heterogeneity of included studies and IA management in MMD patients should be considered in a case-specific manne.

Intracranial Aneurysms in White Patients with Moyamoya Disease: A U.S. Single-Center Case Series and Review

BACKGROUND

Intracranial aneurysms (IA) are associated with moyamoya disease (MMD). There are no clinically tested treatment guidelines. Reporting of cases is vital to better understand the underlying pathophysiology and potential ethnic predispositions and improve patient selection for intervention.

METHODS

Records of all patients diagnosed with MMD with concomitant IA who presented to our institution were retrospectively reviewed. Data related to demographic, clinical, MMD characteristics, aneurysm characteristics, surgical intervention, and follow-up were collected from the records of each patient. Aneurysm location was categorized into circle of Willis (CoW) aneurysms (originating from the CoW or its major branches) and peripheral aneurysms (arising from choroidal or lenticulostriate arteries).

RESULTS

Ten patients were found to have a total of 14 IA. All patients were white. Ten aneurysms (71%) were classified as CoW aneurysms and 4 (29%) were classified as peripheral. Seven of 10 CoW aneurysms (70%) were located in the anterior circulation, whereas 3 (30%) were located in the posterior circulation. Aneurysms of anterior and posterior circulations were most commonly treated with coil embolization, whereas peripheral artery aneurysms were most commonly treated with either cerebral revascularization alone or aneurysm excision.

CONCLUSIONS

Revascularization surgery seems to be an effective method of indirectly treating IA in patients with MMD. Previous literature in addition to our series shows that endovascular embolization is safe and efficacious in treating IA of most locations in patients with MMD. The use of open microsurgery for direct aneurysm treatment in this population poses many challenges.

The prospects and pitfalls in the endovascular treatment of moyamoya disease-associated intracranial aneurysms

Moyamoya disease (MMD) is characterized by progressive stenosis or occlusion of the distal internal carotid artery and simultaneous formation of collateral vasculature. The fragile alteration and increased hemodynamic stress in the intra- and extracranial vasculature would conjointly result in the formation of intracranial aneurysms in MMD patients. According to our classification, the MMD-associated aneurysms are divided into the major artery aneurysms (MAAs) and non-MAAs. The non-MAAs are further subdivided into the distal choroidal artery aneurysms, moyamoya vessel aneurysms, transdural collateral aneurysms, and anastomosis aneurysms. Currently, endovascular treatment (EVT) has become the main stream for the MMD-associated aneurysms. There is no difference to EVT for the MMD-associated MAAs of the non-stenosed major arteries with that in the non-MMD patients. While it is a big challenge to perform EVT for MMD-associated aneurysms in the stenosed arteries. Generally speaking, the parent arteries of the non-MAAs are slim, and super-selective catheterization is technically difficult. Most of the times, parent artery occlusion with liquid embolic agents or coils can only be performed. The vasculature in MMD patients is fragile; perioperative management and meticulous intraoperative manipulation are also very important to avoid complications during EVT. In spites of the complications, the EVT can bring good outcome in selected cases of MMD-associated aneurysms.

Association Between Champagne Bottle Neck Sign of Internal Carotid Artery and Ipsilateral Hemorrhagic Stroke in Patients with Moyamoya Disease

OBJECTIVE

To assess association between champagne bottle neck sign (CBNS) in carotid artery and intracranial hemorrhage in patients with moyamoya disease (MMD).

METHODS

This retrospective study included 76 consecutive patients with MMD without definite risk factors associated with intracranial hemorrhage who underwent preoperative angiography from January 2016 to December 2017. CBNS was defined as luminal diameter ratio of internal carotid artery/common carotid artery ≤0.5 on angiography. The right and left cerebral hemisphere in each patient was separately identified as hemorrhagic and nonhemorrhagic. Association between CBNS and intracranial hemorrhage was analyzed.

RESULTS

Of 76 patients with MMD, intracranial hemorrhage was found in 44 of 152 (28.9%) hemispheres, and 6.8% (3/44) had multiple events. Comparing carotid arteries without intracranial hemorrhage in ipsilateral hemispheres, patients with intracranial hemorrhage in the ipsilateral hemisphere had significantly smaller luminal diameter ratio of internal carotid artery/common carotid artery (0.49 ± 0.11 vs. 0.55 ± 0.12, P < 0.01) and higher prevalence of CBNS (63.7% vs. 41.7%, P = 0.01). Comparing hemispheres with intracranial hemorrhage, patients with ipsilateral carotid artery CBNS had significantly higher prevalence of hemorrhage in posterior territories than patients without CBNS (57.1% vs. 23.1%, P = 0.05). Logistic regression revealed that CBNS was significantly associated with ipsilateral intracranial hemorrhage before (odds ratio = 2.45; 95% confidence interval, 1.19-5.05; P = 0.02) and after (odds ratio = 3.43; 95% confidence interval, 1.50-7.87; P < 0.01) adjusting for female sex, lenticulostriate anastomosis, and choroidal anastomosis.

CONCLUSIONS

CBNS is significantly associated with intracranial hemorrhage in the ipsilateral hemisphere in patients with MMD, particularly intracranial hemorrhage in posterior territories.

Characteristics and Endovascular Management of the Posterior Cerebral Artery Anterior Temporal Branch Aneurysms

PURPOSE

To investigate characteristics of the posterior cerebral artery anterior temporal branch aneurysm and the safety and efficacy of endovascular management.

MATERIALS AND METHODS

A total of 6 patients with anterior temporal branch aneurysms were enrolled. All 6 patients had concurrent occlusion of the ipsilateral anterior circulating arteries. The aneurysms ranged from 2.5 to 5.0 mm. All patients were treated and followed up.

RESULTS

Four unruptured aneurysms were treated with coil embolization of the aneurysm sac only, with the parent artery maintained in 2 patients, slow flow in the parent artery in one and thrombosis at the aneurysm neck leading to parent artery occlusion in the last one. One patient with subarachnoid hemorrhage was treated with coil embolization of both the aneurysm and the parent artery, and the last patient with subarachnoid hemorrhage was treated with the Glubran 2 glue to embolize both the aneurysm and the parent artery. One patient with subarachnoid hemorrhage died of lung complication after embolization. Followed up for 3 months to 1 year, the 4 patients with unruptured aneurysms had no symptoms, including 1 patient with slow flow in the anterior temporal artery and 1 patient with thrombosis and parent artery occlusion. The remaining patient with parent artery occlusion had a good recovery.

CONCLUSIONS

The anterior temporal artery aneurysm is a special subtype of aneurysm and can be readily misdiagnosed as on the posterior cerebral artery trunk or the superior cerebellar artery. Endovascular management has a greater success rate, good effect, and fewer complications but with greater difficulties.