Incidental major artery aneurysms in patients with non-hemorrhagic moyamoya disease

Risk factors of rupture and mortality for intracranial aneurysms associated with moyamoya disease: a multicenter retrospective study

OBJECTIVE

The aim of this study was to analyze the risk factors for aSAH and subsequent death in patients with MMD.

METHODS

Chinese Multi-Center Cerebral Aneurysm Database (CMAD) is a multicenter study registered in China. From 2016 to 2021, 181 patients with MMD in CMAD. Logistic regression analysis was used to identify risk factors for intracranial aneurysm rupture. Univariate and multivariate Cox regression were used to risk factors associated with ruptured intracranial aneurysm patients with MMD follow-up events (death). Cumulative survival was described using the Kaplan‒Meier technique.

RESULTS

Of 11,686 IA patients, 181 (1.5%) had MMD. In the study, 158 patients with MMD were enrolled. There were 53 ruptured aneurysms and 105 unruptured aneurysms. In multivariate analysis, age (≥ 60 years OR 2.350 [1.008-5.478]), location (middle cerebral artery OR5.431 [1.347-21.889]; posterior circulation arteries OR 3.189 [1.110-9.163]) and aneurysm size (≥ 5 mm OR 2.855 [1.274-6.397], P = 0.011) were associated with intracranial aneurysm rupture in patients with MMD. In the 2-year follow-up time of aSAH patients, 44% (22/50) had favorable outcomes, 14% (7/50) had unfavorable outcomes and 42% (21/50) had death. Hypertension (HR 6.643 [1.620-27.244], P = 0.009) and Hunt-Hess grade (H&H grade IV HR 14.852 [3.151-70.011], P = 0.001; H&H grade V HR 17.697 [3.046-102.842], P = 0.001) were associated with increased mortality. In contrast, both ST (HR 0.168 [0.031-0.921], P = 0.04) and ET (HR 0.289 [0.087-0.957], P = 0.042) achieved good results.

CONCLUSIONS

This study showed that the proportion of MMD in IA patients was approximately 1.5% (181/11686). For patients with cerebral ischemia on admission, revascularization may prevent the rupture of intracranial aneurysms. Age ≥ 60 years, location, and aneurysm size ≥ 5 mm were associated with IA rupture. Further analysis showed that being located in the middle cerebral artery was the most relevant risk factor for rupture. Patients with ruptured IA who underwent ST or ET had better clinical outcomes and survival than those who underwent CT; however, hypertension and poor initial Hunt-Hess grade were independent predictors of death.

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.

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.

Pseudoaneurysm as a differential for the computed tomography angiography “spot sign” in atypical presentations of intracerebral hemorrhage: illustrative case

BACKGROUND

The computed tomography angiography (CTA) “spot sign” is a well-recognized radiographic marker in primary intracerebral hemorrhage (ICH). Although it has been demonstrated to represent an area of active hemorrhage or contrast extravasation, the exact pathophysiology remains unclear. Vascular mimics of the spot sign have been identified; however, those representing pseudoaneurysm and small vessel aneurysm have rarely been reported.

OBSERVATIONS

A 57-year-old female with a past medical history of hypertension and diabetes mellitus presented with 2 weeks of acute-onset, worsening headache. Computed tomography scanning showed a right interior frontal lobe intraparenchymal hemorrhage. CTA demonstrated a punctate focus of hyperattenuation within the hematoma, consistent with a spot sign, which corresponded to a distal anterior cerebral artery pseudoaneurysm on a cerebral angiogram. The patient subsequently underwent emergent resection of the pseudoaneurysm and hematoma evacuation without complications. Her postoperative course was unremarkable without acute concerns or residual symptoms at the 4-month follow-up.

LESSONS

The authors present a unique case of a distal anterior cerebral artery pseudoaneurysm presenting as a spot sign in a relatively young patient without underlying vascular disease. Given the need for emergent intervention, intracranial pseudoaneurysm is an important diagnosis to consider in the presence of a spot sign in atypical clinical presentations of primary ICH.

Endovascular treatment of main trunk aneurysms in the residual anterior circulation in moyamoya disease

BACKGROUND

Main trunk aneurysms in the residual anterior circulation in moyamoya disease (MMD) are uncommon, and in such cases, endovascular treatment (EVT) is a good choice.

MATERIALS AND METHODS

A retrospective study was performed on 35 consecutive patients admitted to our hospital who were diagnosed with MMD and main trunk aneurysms in the residual anterior circulation and were treated with EVT.

RESULT

The 35 patients were aged 38-77 years (mean, 56.1 ± 8.8 years) and included 17 females (48.6%, 17/35). There were 29 cases (82.9%, 29/35) of hemorrhagic onset. In 35 patients, there were 38 main trunk aneurysms in the residual anterior circulation. Thirty-eight aneurysms underwent coiling; among them, coiling with stent assistance was used in the treatment of 6 (15.8%, 6/38) aneurysms. The immediate modified Raymond-Roy classification (MRRC) was grade I for all aneurysms. Among 35 patients, intraoperative bleeding occurred in 2 (5.7%, 2/35) patients. After EVT, immediate hemiplegia occurred in 4 (11.4%, 4/35) patients, and immediate coma occurred in 1 (2.9%, 1/35) patient. At discharge, in 35 patients, the Glasgow Outcome Scale (GOS) was five in 88.6% of them. Of 35 patients, 68.6% had follow-up data, GOS was five in 87.5% patients, and the MRRC was grade I for all aneurysms in the follow-up angiography.

CONCLUSION

For main trunk aneurysms in the residual anterior circulation in MMD, although EVT was accompanied by potential ischemic and hemorrhagic complications, which should be considered, EVT can still offer an acceptable prognosis in more than 85% of patients.

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.

Clinical Features and Treatment Outcomes of Cerebral Arteriovenous Malformation Associated With Moyamoya Disease

BACKGROUND

Cerebral arteriovenous malformation (AVM) can rarely occur in conjunction with moyamoya disease (MMD). There is still no consensus on how to treat AVM when accompanied by MMD. In this study, we assessed the clinical features and suggested appropriate management when AVM was combined with MMD.

METHODS

From August 1994 to December 2020, 7 out of 4004 patients with MMD were found to have AVM. The Karnofsky Performance Scale (KPS) was used to evaluate the clinical outcomes of AVM and MMD. KPS greater than 80 was classified as a good outcome. In addition, the radiologic outcomes of the patients were evaluated.

RESULTS

The incidence of AVM with MMD was 1.7 per 1000 persons. Five patients underwent bypass surgery for MMD, and 5 patients underwent Gamma Knife surgery (GKS) for concurrent AVM. Postoperative perfusion magnetic resonance imaging and brain single photon emission computerized tomography showed improved cerebral hemodynamics in 4 out of 7 territories. Postoperative cerebral angiography showed good revascularization in 4 out of 8 territories. After GKS, 4 patients showed complete obliteration, and 1 patient showed a significantly decreased AVM size. Six patients showed favorable clinical outcomes (KPS 80-100), and 1 patient with delayed GKS for AVM had a poor outcome (KPS 20) due to AVM rupture.

CONCLUSIONS

In this study, AVM tended to occur where the angiographic stage of MMD was higher. When AVM is combined with MMD, MMD bypass surgery is recommended based on symptoms and cerebral perfusion status. For AVM, less invasive but effective treatments, such as GKS, should be implemented as soon as possible.

Clinical features of and risk factors for intracranial aneurysms associated with moyamoya disease

BACKGROUND

The clinical features of aneurysms associated with moyamoya disease (MMD) and risk factors for the formation and rupture of aneurysms are not well defined.

AIMS

In this study, we retrospectively analyzed clinical data of MMD patients and examined the potential risk factors for the formation and rupture of aneurysms in these patients.

METHODS

The medical records of all MMD patients in our hospital from April 2012 to May 2019 were reviewed. The logistic regression analysis was used to determine the independent association between various potential risk factors and the presence or rupture of intracranial aneurysms in MMD patients.

RESULTS

Of 2230 MMD patients, 182 (8.2%) cases had intracranial aneurysms. The mean age of onset in patients with aneurysms was 47.2 years, which was significantly higher when compared with those without aneurysms (p < 0.001). In logistic regression analysis, age of onset remained significantly associated with the presence of intracranial aneurysms, while female gender, hypertension, diabetes mellitus, and coronary artery disease were not. Besides, intracranial aneurysms were significantly associated with intracranial hemorrhage in MMD patients (odds ratio [OR] = 5.19; 95% confidence interval [CI], 3.80-7.09). About 60% aneurysms >5 mm in size, and 62.1% aneurysms with irregularly shaped morphology were ruptured. Aneurysms located in basilar tip, collateral or moyamoya vessels were more likely to present with rupture.

CONCLUSIONS

Age was an important risk factor for intracranial aneurysms formation in MMD patients. Aneurysms increased the risk of intracerebral hemorrhage in MMD patients, and their ruptures were correlated with aneurysms size, location, and morphology.

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.

Treatment strategies of ruptured intracranial aneurysms associated with moyamoya disease

OBJECTIVE

The purpose of this study was to present our experience in the management of ruptured intracranial aneurysms associated with moyamoya disease (MMD), and to discuss their treatment strategies and the timing of revascularization surgery.

PATIENTS AND METHODS

Thirteen patients who had ruptured intracranial aneurysms associated with MMD were enrolled in this study. Different treatment strategies were adopted based on the location of the aneurysms. Their clinical and radiologic features, treatment selection and outcomes were retrospectively reviewed.

RESULTS

Among the five patients with major artery aneurysms in anterior circulation, three were embolized and two clipped. Among the five patients with major artery aneurysms in posterior circulation, three were treated by endovascular coiling. Among the three peripheral aneurysms, one was treated by endovascular embolization, one by aneurysmectomy, and the other one by revascularization alone. For the patients whose aneurysms were treated by endovascular embolization or surgery, a staged revascularization was performed on day 28 to day 87 after the first operation. For the two patients with aneurysms untreated directly, the timing of revascularization was 20 days and 54 days after hemorrhage, respectively. During the follow-up recurrent intracranial hemorrhage occurred in a patient, but not caused by the previous aneurysm. No other patients suffered recurrent intracranial hemorrhage or ischemic stroke. Complete occlusion was achieved in all the 11 aneurysms that had been clipped or embolized. Of the remaining three aneurysms that had not been directly treated, one disappeared spontaneously, whereas the other two remained stable. The direct and indirect bypasses were confirmed patent in the 11 patients who had undergone revascularization.

CONCLUSION

Our current treatment strategies and timing of revascularization may provide a benefit for the patients with MMD accompanied by ruptured 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.

Spontaneous recession of a posterior cerebral artery aneurysm concurrent with carotid rete mirabile and moyamoya-pattern collateral vessels: a case report

Background

Carotid rete mirabile (RM) is a meshwork of multiple, freely intercommunicating arterioles that reconstitute the absent or hypoplastic segments of the internal carotid artery (ICA). Carotid RM has been reported to be associated with cerebrovascular diseases. However, it is rarely associated with moyamoya-pattern collateral vessels in the posterior cerebral artery (PCA) region and aneurysm.

Case presentation

A 39-year-old woman was admitted complaining of sudden-onset headache, nausea, and vomiting. Further investigation revealed subarachnoid hemorrhage (SAH), carotid RM, a moyamoya collateral pattern in the PCA region, and a pseudoaneurysm in the moyamoya-like vessels. The patient was treated conservatively, recovered well and was discharged 1 week later. Follow-up angiography showed that the aneurysm had disappeared.

Conclusions

As shown by the present case, we believe that carotid RM could occur in combination with moyamoya-pattern collateral vessels in the PCA region; aneurysms can occur in the moyamoya-like vascular network. Congenital etiology may be the reason for these combinations. Based on our approach in this case, aneurysm located in moyamoya-like vessels can disappear spontaneously after conservative treatment.

Treatment of aneurysms in patients with moyamoya disease: a 10-year single-center experience

OBJECTIVE

Moyamoya disease (MMD) is occasionally accompanied by intracranial aneurysms. The purpose of this study was to delineate the efficacy of the authors’ current surgical strategy in the management of MMD-associated aneurysms of different types.

METHODS

Between January 2007 and March 2016, a consecutive cohort of 34 patients with 36 MMD-associated aneurysms was enrolled in this prospective single-center cohort study. The lesions were classified as peripheral (17 aneurysms) or main trunk aneurysms (13 in the anterior circulation and 6 in the posterior circulation). For the peripheral aneurysms, revascularization with or without endovascular treatment was suggested. For the main trunk aneurysms, revascularization alone, revascularization with aneurysm clipping, or revascularization with aneurysm embolization were used, depending on the location of the aneurysms.

RESULTS

Of the peripheral aneurysms, 4 were treated endovascularly with staged revascularization, and 13 were treated solely with cerebral revascularization. Of the 13 main trunk aneurysms in the anterior circulation, 10 were clipped followed by revascularization, and 3 were coiled followed by staged cerebral revascularization. Of the 6 main trunk aneurysms in the posterior circulation, 4 underwent endovascular coiling and 2 were treated solely with revascularization. One patient died of contralateral intracerebral hemorrhage 6 months after the operation. No other patients suffered recurrent intracranial hemorrhage, cerebral ischemia, or aneurysm rupture. An angiographic follow-up study showed that all the bypass grafts were patent. Complete occlusion was achieved in all 21 aneurysms that were clipped or embolized. Of the remaining 15 aneurysms that were not directly treated, 12 of 13 peripheral aneurysms were obliterated during the follow-up, whereas 1 remained stable; 1 of 2 posterior main trunk aneurysms remained stable, and the other became smaller.

CONCLUSIONS

The authors’ current treatment strategy may benefit patients with MMD-associated aneurysms.

Keyhole Supraorbital Craniotomy for Aneurysm Clipping in the Setting of Bypass for Moyamoya Disease

BACKGROUND

In 3%-15% of patients with moyamoya disease, aneurysms occur throughout the circle of Willis. In moyamoya patients treated with a superficial temporal artery-to-middle cerebral artery (STA-MCA) bypass, treatment of a new or an enlarging aneurysm can be complicated by the presence of the bypass and by limitations on the use of standard frontotemporal craniotomies to gain access to the aneurysm. Furthermore, endovascular access can be limited by the presence of fragile moyamoya vessels and precluded by atresia of large vessels.

CASE DESCRIPTION

A 45-year-old female patient with a history of moyamoya disease and previous left STA-MCA bypass presented with an enlarging left superior cerebellar artery aneurysm. We used a keyhole supraorbital craniotomy as a minimally invasive route to treat this aneurysm of the circle of Willis, with minimal interruption to the existing bypass or collateral circulation.

CONCLUSIONS

In patients with moyamoya disease who have existing STA-MCA bypass and de novo or expanding aneurysms, treatment is fraught with challenges. We advocate the use of a minimally invasive keyhole supraorbital craniotomy with an eyebrow incision for aneurysms associated with moyamoya disease occurring on the proximal anterior cerebral and middle cerebral arteries, the anterior communicating artery, the basilar apex, the posterior communicating artery, the proximal superior cerebellar artery, and the posterior cerebral artery.

Coexisting vascular lesions in reversible cerebral vasoconstriction syndrome

Background

The pathophysiology of reversible cerebral vasoconstriction syndrome (RCVS) is not known. Published cases have documented coexisting cervical artery dissection and unruptured aneurysms, raising the possibility that ultrastructural vessel wall abnormalities underlie the development of vascular lesions as well as RCVS.

Methods

In this retrospective study we compared the frequency of neurovascular abnormalities in 158 consecutive RCVS patients, 44 patients with primary angiitis of the central nervous system (PACNS, positive controls), and 177 non-stroke patients with acute neurological symptoms (non-arteriopathy controls).

Results

Coexisting neurovascular abnormalities were significantly higher ( p < 0.001) in RCVS (23%) as compared to the PACNS (5%) or non-arteriopathy groups (8%). Cervical artery dissections were noted only in the RCVS group (8%, p < 0.001). The RCVS group had more unruptured aneurysms than PACNS (13% vs. 5%, p = 0.099) or non-arteriopathy controls (13% vs. 7%, p = 0.05). Seven RCVS patients also had other vascular malformations (venous anomaly, cavernous malformations, fibromuscular dysplasia). There was no significant association between coexisting vascular abnormalities and brain lesions or discharge clinical outcome in the RCVS group.

Conclusion

The high prevalence and heterogeneous anatomy of coexisting vascular lesions suggest that subtle ultrastructural arterial wall abnormalities may contribute to their development and also predispose to RCVS.

Moyamoya disease associated with arteriovenous malformation and anterior communicating artery aneurysm: A case report and literature review

Moyamoya disease (MMD) can be associated with an aneurysm or arteriovenous malformation (AVM). However, no case of MMD simultaneously associated with both intracranial aneurysm and AVM has been previously reported. The present study reports the case of a patient with MMD simultaneously associated with both aneurysm and AVM. The patient was a 46-year-old woman presenting with a subarachnoid hemorrhage whose imaging diagnosis of MMD was associated with an aneurysm and AVM. The aneurysm was located in the anterior communicating artery, which was similar to a berry aneurysm caused by hemodynamics. The AVM was located in the posterior circulation. Beyond the presentation of the posterior cerebral artery, the appearance of an artery supplying blood from the middle cerebral artery supported the view that the AVM was congenital and unruptured. Conservative treatment was provided and examination of the patient at follow-up showed good recovery. In addition to the case report, the present study also reviewed the relevant literature in order to compile information on MMD associated with both an aneurysm and AVM.

Treatment strategies for aneurysms associated with moyamoya disease

The treatment of aneurysms associated with moyamoya disease (MMD) is difficult for neurosurgeons, and little is known of strategy options. This report constitutes a comprehensive review of the literature. We summarize the known treatments and their clinical outcomes according to the site of the aneurysm: in major arteries, peripheral arteries, moyamoya vessels, meningeal arteries, or at the site of anastomosis. The literature review indicates that the treatment of MMD-associated aneurysms varies according to the site of the aneurysm and its hemodynamic characteristics. In particular, the treatment for basilar tip aneurysms remains challenging, since both endovascular embolization and direct clipping are difficult. The potential risk for ischemia should be considered in selecting endovascular or surgical approaches. Revascularization surgery, which is important for the treatment of MMD, also determines the clinical treatment outcome of aneurysms associated with MMD.

Resolution of bilateral moyamoya associated collateral vessel aneurysms: Rationale for endovascular versus surgical intervention

BACKGROUND

Management of aneurysms associated with deep collateral vessels in moyamoya disease is challenging both from an endovascular and a surgical standpoint. Difficulties with access or localization, and compromise of the collateral circulation with subsequent ischemia are the primary concerns, making direct obliteration potentially unfeasible or risky. Alternatively, superficial temporal artery-middle cerebral artery bypass is another potential strategy for resolution of these aneurysms.

CASE DESCRIPTION

Presented are the findings and management for a patient with moyamoya disease and bilateral deep collateral vessel aneurysms, successfully treated with endovascular obliteration following a right-sided hemorrhage and subsequently with bypass for an unruptured but growing contralateral aneurysm.

CONCLUSIONS

A rationale and approach to management is outlined, as derived from review of the current literature and the illustrative case with bilateral collateral vessel aneurysms.