Hemorrhagic Moyamoya Disease Treatment: A Network Meta-Analysis

Combined Direct and Indirect Revascularization for Adults with Moyamoya Disease: A Single-Center Retrospective Study

Background  Moyamoya vasculopathy is a rare neurological disease characterized by the progressive constriction of major intracranial vessels and secondary collateral formation. In the past decade, the popularity of combined bypass surgery has increased. They take advantage of the quick perfusion of direct bypass and collaterals ingrowth from indirect bypass. Objective  This study aimed to describe a single-center experience with surgical management of moyamoya disease (MMD) and moyamoya syndrome (MMS) over 7 years. Materials and Methods  In this retrospective medical records review, we enrolled patients diagnosed with MMD and MMS who were treated with combined surgical revascularization at the Hamad Medical Corporation center between 2015 and 2022. SPSS 26.0 was used to analyze the data. Results  A total of 20 patients were included, with 15% having MMS. The mean age was 37.4 ± 10.26 years, and 60% of them were males. The mean follow-up period was 13.6 months. The modified Rankin score was significantly decreased by 1.9 ± 2.1, p  = 0.0001. Following surgery, no deficits were observed in 16 cases, whereas three were not improved, and one died. Following up on the stroke status, one patient developed a hemorrhagic stroke, and another showed right-side numbness. The postoperative status was substantially linked with the initial clinical presentation ( p  = 0.004). Conclusion  Combined direct and indirect surgical revascularization procedures have favorable outcomes in MMD and MMS patients. Additional rigorous, prospective, controlled, high-quality trials with large-sample are needed to support our results.

Natural course of hemodynamically stable hemispheres contralateral to operated hemispheres in adult patients with ischemic moyamoya diseases

The necessity of bilateral bypass in adult moyamoya disease (MMD) remains unclear despite its recommendation for pediatric and hemorrhagic cases. We aimed to investigate the natural course of hemodynamically stable unoperated hemispheres after bypass surgery for symptomatic and hemodynamically unstable hemispheres in adult patients with ischemic MMD. Among 288 patients, the mean age at the first operation of the unstable hemispheres was 40.8 ± 12.2 years. The mean follow-up period was 62.9 ± 46.5 months. 45 patients (15.6%) experienced stroke events in the unoperated hemisphere, consisting of hemorrhagic stroke in 8 (2.8%) and ischemic stroke in 37 (12.8%), including progressive transient ischemic attack in 25 (8.7%) and infarction in 12 (4.2%). Among them, 39 patients (13.5%) underwent bypass surgery. The annual risk of total stroke is 3.0%/patient-year, with 2.5% for ischemic stroke and 0.5% for hemorrhagic stroke. The 5- and 10-year cumulative risks of ischemic stroke were 13.4% and 18.3%, respectively, and those of hemorrhagic stroke were each 3.2%. The natural course of hemodynamically stable hemispheres contralateral to the operated ones appeared fairly good. Additional bypass surgery on the unoperated hemispheres should be considered for symptomatic and hemodynamically unstable hemispheres in adult patients with ischemic MMD during the follow-up.

Association of Bypass Surgery and Mortality in Moyamoya Disease

Background Patients with moyamoya disease (MMD) have a high risk of stroke or death. We investigated whether extracranial to intracranial bypass surgery can reduce mortality by preventing strokes in patients with MMD. Methods and Results This nationwide retrospective cohort study encompassed patients with MMD registered under the Rare Intractable Diseases program via the Relieved Co-Payment Policy between 2006 and 2019, using the Korean National Health Insurance Service database. Following a 4-year washout period, landmark analyses were employed to assess mortality and stroke occurrence between the bypass surgery group and the nonsurgical control group at specific time points postindex date (1 month and 3, 6, 12, and 36 months). The study included 18 480 patients with MMD (mean age, 40.7 years; male to female ratio, 1:1.86) with a median follow-up of 5.6 years (interquartile range, 2.5-9.3; mean, 6.1 years [SD, 4.0 years]). During 111 775 person-years of follow-up, 265 patients in the bypass surgery group and 1144 patients in the nonsurgical control group died (incidence mortality rate of 618.1 events versus 1660.3 events, respectively, per 105 person-years). The overall adjusted hazard ratio (HR) revealed significantly lower all-cause mortality in the bypass surgery group from the 36-month landmark time point, for any stroke mortality from 3- and 6-month landmark time points, and for hemorrhagic stroke mortality from the 6-month landmark time point. Furthermore, the overall adjusted HRs for hemorrhagic stroke occurrence were beneficially maintained from all 5 landmark time points in the bypass surgery group. Conclusions Bypass surgery in patients with MMD was associated with a lower risk of all-cause and hemorrhagic stroke mortality and hemorrhagic stroke occurrence compared with nonsurgical control.

Adult Moyamoya Disease and Syndrome: Current Perspectives and Future Directions: A Scientific Statement From the American Heart Association/American Stroke Association

Adult moyamoya disease and syndrome are rare disorders with significant morbidity and mortality. A writing group of experts was selected to conduct a literature search, summarize the current knowledge on the topic, and provide a road map for future investigation. The document presents an update in the definitions of moyamoya disease and syndrome, modern methods for diagnosis, and updated information on pathophysiology, epidemiology, and both medical and surgical treatment. Despite recent advancements, there are still many unresolved questions about moyamoya disease and syndrome, including lack of unified diagnostic criteria, reliable biomarkers, better understanding of the underlying pathophysiology, and stronger evidence for treatment guidelines. To advance progress in this area, it is crucial to acknowledge the limitations and weaknesses of current studies and explore new approaches, which are outlined in this scientific statement for future research strategies.

Larger Posterior Revascularization Associated with Reduction of Choroidal Anastomosis in Moyamoya Disease: A Quantitative Angiographic Analysis

BACKGROUND AND PURPOSE

Choroidal anastomosis, a hemorrhage-prone periventricular collateral manifestation in Moyamoya disease, outflows to the cortex posterior to the central sulcus. The objective of the present study was to test whether the angiographic extent of revascularization posterior to the central sulcus contributes to the postoperative reduction of choroidal anastomosis.

MATERIALS AND METHODS

This retrospective cohort study included choroidal anastomosis-positive hemispheres before direct bypass surgery. The postoperative reduction of choroidal anastomosis was determined by a consensus of 2 raters according to the previous research. An imaging software automatically traced the angiographic revascularization area, which was subsequently divided into anterior and posterior parts by an anatomic line corresponding to the central sulcus. Each area was quantitatively measured as a percentage relative to the whole supratentorial area.

RESULTS

Postoperative reduction of choroidal anastomosis was achieved in 68 (85.0%) of the 80 included hemispheres. The revascularization area posterior to the central sulcus was significantly larger in the hemispheres with reduction than in those with no reduction (mean, 15.2% [SD, 7.1%] versus 4.2% [SD, 3.4%], P < .001), whereas no significant difference was observed in the revascularization area anterior to the central sulcus. Multivariate analysis revealed that the revascularization area posterior to the central sulcus was the only significant factor associated with reduction (OR, 1.57; 95% CI, 1.21-2.03, for every 1% increase).

CONCLUSIONS

The results suggest that a larger revascularization posterior to the central sulcus is associated with postoperative reduction of choroidal anastomosis regardless of the extent of anterior revascularization. It might facilitate optimal selection of the revascularization site for preventing hemorrhage.

Surgical techniques and indications for treatment of adult moyamoya disease

Moyamoya disease (MMD) is a chronic, progressive cerebrovascular disease involving the occlusion or stenosis of the terminal portion of the internal carotid artery (ICA) and the proximal anterior and middle cerebral arteries. Adults with MMD have been shown to progressively accumulate neurological and cognitive deficits without treatment, with a mortality rate double that of pediatric patients with MMD. Surgical intervention is the mainstay of treatment to prevent disease progression and improve clinical outcomes. Several different types of bypasses can be utilized for revascularization in MMD, including indirect, direct, and combined forms of extracranial-to-intracranial (EC-IC) bypass. Overall, the choice of appropriate technique requires consideration of the age of the patient, preoperative hemodynamics, neurologic status, and territories most at risk and in need of revascularization. Here, we will review the indications and surgical techniques for the treatment of adult MMD. Step-by-step instructions for performing several bypass variants with technical pearls are discussed.

Delayed Anastomotic Occlusion after Direct Revascularization in Adult Hemorrhagic Moyamoya Disease

Delayed anastomotic occlusion occurred in a considerable proportion of hemorrhagic moyamoya disease (MMD) patients undergoing direct revascularization. This study aimed to investigate the predictors and outcomes of delayed anastomotic occlusion in adult hemorrhagic MMD. The authors retrospectively reviewed 87 adult hemorrhagic MMD patients. Univariate and multivariate logistic regression analyses were performed. After an average of 9.1 ± 6.9 months of angiographic follow-up, the long-term graft patency rates were 79.8%. The occluded group had significantly worse angiogenesis than the non-occluded group (p < 0.001). However, the improvement of dilated anterior choroidal artery–posterior communicating artery was similar (p = 0.090). After an average of 4.0 ± 2.5 years of clinical follow-up, the neurological statues and postoperative annualized rupture risk were similar between the occluded and non-occluded groups (p = 0.750; p = 0.679; respectively). In the multivariate logistic regression analysis, collateral circulation Grade III (OR, 4.772; 95% CI, 1.184–19.230; p = 0.028) and preoperative computed tomography perfusion (CTP) Grade I–II (OR, 4.129; 95% CI, 1.294–13.175; p = 0.017) were independent predictors of delayed anastomotic occlusion. Delayed anastomotic occlusion in adult hemorrhagic MMD might be a benign phenomenon. Good collateral circulation (Grade III) and compensable preoperative intracranial perfusion (CTP Grade I–II) are independent predictors for this phenomenon. Moreover, the delayed anastomotic occlusion has no significant correlations with the long-term angiographic and neurological outcomes, except neoangiogenesis.

Stress and mood of adults with moyamoya disease: A cross-sectional study

Moyamoya disease in adults is a chronic, progressive disorder characterized by fine collateral vessel networks in the brain. The disorder can lead to negative mood and stress, which, left unresolved, may increase adverse health outcomes. We conducted a cross-sectional survey to examine stress and mood of adults with moyamoya disease. Participants were recruited at a university hospital in Seoul, Korea. Data were collected through questionnaires and review of participants' electronic medical records. A total of 109 adults participated. Significant correlations were found between perceived stress, anxiety, and depression. Adults with moyamoya disease experience anxiety, depression, and stress related to the risk of cerebral hemorrhage or ischemia, similar to those with other cerebrovascular disease. If negative mood and stress were uncontrolled, those can cuase adverse health outcomes. Health professionals caring for people with moyamoya disease should carefully observe their stress and mood and develop interventions tailored to stages of disease to help them manage. The study results provide baseline information for understanding the level of, and the factors associated with, stress and mood.

Quantitative Angiographic Hemodynamic Evaluation After Revascularization Surgery for Moyamoya Disease

The corresponding hemodynamic changes of the internal carotid artery (ICA) after the revascularization surgery for moyamoya disease (MMD) remain unclear. The aim of this study was to analyze the hemodynamic changes of the ipsilateral ICA after the combined direct and indirect extracranial-intracranial (EC-IC) bypass. MMD patients undergoing combined EC-IC bypass were retrospectively reviewed. The mean transit time (MTT) of ICA was evaluated by color-coding angiography before revascularization and at follow-up. The MTT defined as the blood transit time between the end of cervical portion (C1) and the C7 segment of ICA. The clinical prognosis was assessed with Matsushima grading system, moyamoya vessel reduction system, and modified Rankin Scale (mRS). The correlation between hemodynamic parameter and prognosis was analyzed. Subgroup analysis was conducted between different presentations and different ages. Fifty-one patients were identified and the mean imaging follow-up interval was 5.5 months. The ICA-MTT was increased after the combined revascularization (P < 0.001) compared with contralateral ICA. Faster preoperative ICA-MTT was significantly associated with improved mRS in the ischemic group (P = 0.05). The increased ICA-MTT was significantly associated with favorable neoangiogenesis (P = 0.04), moyamoya vessel reduction (> 50%) (P = 0.023), and improved mRS score (P = 0.008). In subgroup analysis, the correlation in the ischemic subgroup and adult subgroup remained significant. In this cohort, the ICA-MTT increased after the combined EC-IC bypass, and there was a positive correlation between the increased blood transit time and favorable outcomes. Color-coding DSA proved to be useful as a quantitative and serial method to monitor postoperative courses after revascularization in MMD.

Postoperative collateral formation after indirect bypass for hemorrhagic moyamoya disease

Background

The research on postoperative collateral formation for hemorrhagic moyamoya disease (MMD) evaluated by using digital subtraction angiography (DSA) is limited. Our study objective was to investigate the postoperative collateral formation after indirect bypass for hemorrhagic MMD.

Methods

All consecutive inpatients with hemorrhagic MMD who received indirect bypass at Beijing Tiantan Hospital, Capital Medical University from January 2010 through December 2018 were screened. The site of the hemorrhage was classified as either anterior or posterior. Postoperative collateral formation was evaluated on lateral views using the Matsushima scale. Univariate and multivariate logistic regression analyses were carried out to determine the factors influencing postoperative collateral formation.

Results

Six-four patients (64 hemispheres) were included in this study. After a median 8.5 months DSA follow-up, 14 (21.9%) hemispheres had grade A collateral circulation, 13 (20.3%) had grade B, and 37 (57.8%) had grade C. Twenty-seven (42.2%) hemispheres had good postoperative collateral formation and 37 (57.8%) had poor postoperative collateral formation. The univariate logistic regression analyses showed that age at operation (OR, 0.954; 95% CI, 0.908–1.003; p = 0.066), hemorrhagic site (OR, 4.694; 95% CI, 1.582–13.923; p = 0.005), and PCA involvement (OR, 3.474; 95% CI, 0.922–13.086; p = 0.066) may effect postoperative collateral formation. The multivariate logistic regression analyses showed that only anterior hemorrhage (OR, 5.222; 95% CI, 1.605–16.987; p = 0.006) was significantly related to good postoperative collateral formation.

Conclusion

Anterior hemorrhage was significantly related to good postoperative collateral formation after indirect bypass.

Remote ischemic conditioning for the treatment of ischemic moyamoya disease

Aims

This study investigated the safety and efficacy of remote ischemic conditioning (RIC) on ameliorating the sequelae of ischemic moyamoya disease (iMMD).

Methods

A total of 30 iMMD patients underwent long‐term RIC and were followed up at 0.5, 1, and 2 years for clinical outcomes, including frequency of stroke recurrence, Patient Global Impression of Change (PGIC) scale, peak systolic velocities (PSV), and cerebral perfusion.

Results

During the whole RIC treatment process, no RIC‐related adverse event occurred. Only one of 30 patients suffered a onetime infarction (3.3%), and the ratios of acceptable PGIC were 88.2%, 64.3%, and 92.3% at 0.5, 1, and 2 years follow‐up. Kaplan‐Meier analysis showed the frequency of stroke recurrence was significantly reduced after RIC (P = .013). The frequency of TIA per week was 1.1 (0.6, 2.8) prior to RIC and 0.1 (0.0, 0.5) post‐RIC (P < .01). Compared to baseline, PSV values were significantly reduced after RIC treatment (P = .002 at 0.5, P = .331 at 1, and P = .006 at 2 years). In patients undergoing perfusion studies, 75% obtained improvement on followed‐up SPECT and 95% on followed‐up PET maps.

Conclusions

Remote ischemic conditioning may be beneficial on controlling iMMD‐induced ischemic events, relieving symptoms, and improving cerebral perfusion, without incidence of complications in this case series.

Side-to-Side Superficial Temporal Artery to Middle Cerebral Artery Bypass Technique: Application of Fourth Generation Bypass in a Case of Adult Moyamoya Disease

BACKGROUND

Moyamoya disease (MMD) is a rare cause of cerebral hemorrhage and ischemia. Spontaneous development of collateral supply from the external carotid artery (ECA) may limit the use of donor arteries used in standard direct bypass techniques.

OBJECTIVE

To identify the technical feasibility of side-to-side (S-S) superficial temporal artery to middle cerebral artery (STA-MCA) bypass and demonstrate the application of fourth generational bypass techniques in the treatment of MMD.

METHODS

S-S bypass was performed in order to maintain distal outflow in the donor STA. Fourth generation bypass techniques, including atypical anastomosis construction and intraluminal suturing were utilized.

RESULTS

The novel S-S STA-MCA bypass was performed, with patent flow in both recipient MCA and endogenous ECA-ICA collaterals supplied by the distal STA. Technical nuances, including proper alignment of donor vessel, tension reduction, and S-S anastomosis construction with intraluminal suturing technique are essential for successful bypass. Unique flow properties of this bypass were identified, resulting in flow augmentation to the recipient territory compared to standard end-to-side (E-S) techniques.

CONCLUSION

Fourth generational bypass techniques can be successfully applied to MMD, allowing for novel bypass construction. S-S anastomosis can result in potentially beneficial flow properties compared to standard E-S constructions.

The Targeted Bypass Strategy for Preventing Hemorrhage in Moyamoya Disease: Technical Note

Although direct bypass is effective at preventing intracranial hemorrhage in moyamoya disease, the optimal strategy for achieving this purpose has rarely been addressed. The tailored targeting bypass strategy is a novel technical modification of direct bypass focused on hemorrhage prevention. The strategy is based on the promising theory of periventricular anastomosis, which explains the mechanism of hemorrhage in moyamoya disease. The strategy is defined as the use of multi-imaging modalities to predetermine in a tailored manner a target vessel at the point at which the medullary artery directly extends from the periventricular anastomosis of interest. Direct bypass with a wide craniotomy was performed on 13 hemispheres in eight patients according to this strategy. Marked shrinkage of the periventricular anastomosis of interest was observed in all but one hemisphere after surgery, and no new hemorrhages have occurred as of this writing. The present case series illustrates the technical aspects and preliminary results of the tailored targeting bypass strategy, an approach that might expand the potential of direct bypass in preventing hemorrhage.

Evaluation of Hemodynamics Before and After Revascularization in Hemorrhagic Moyamoya Disease: A Computed Tomography Perfusion Imaging Case Study

OBJECTIVE

To explore the feasibility of computed tomography perfusion imaging (CTP) for evaluating hemodynamics in hemorrhagic moyamoya disease (MMD).

METHODS

The retrospective analysis included 25 patients with hemorrhagic MMD who underwent brain CTP examination. Two experienced radiologists manually delineated regions of interest (ROIs) in the bilateral frontal lobe, temporal lobe, brain tissue adjacent to the hemorrhagic foci, and brainstem as a control region. The perfusion values for all ROIs were extracted, including cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and time to peak (TTP). Subsequently, the differences in perfusion values for different brain tissues were compared between the hemorrhagic side and the nonhemorrhagic side. For patients who underwent revascularization surgery, differences in perfusion values from before to after surgery were determined in brain tissues on the ipsilateral side.

RESULTS

CBF in the area around the hematoma and the lateral temporal lobe on the hemorrhage hemisphere was lower than that on the contralateral side, whereas TTP and MTT were higher. Among the 14 patients who underwent revascularization, CBF and CBV in the postoperative temporal lobes were higher than the preoperative values, whereas TTP and MTT were lower. CBF and CBV in the frontal lobe were higher after the operation.

CONCLUSIONS

Hemorrhagic MMD results in cerebral ischemia, and CTP could be used to localize such ischemic brain tissue and objectively evaluate the changes in cerebral hemodynamics with revascularization.

Prognostic factors for adult patients with hemorrhagic moyamoya disease in the acute stage

OBJECTIVES

Hemorrhagic moyamoya disease (MMD) is one common subtype in adult patients. However, the study about outcome of hemorrhagic MMD patients in the acute stage is still lacking. This study is aimed to explore the short-term prognostic factors for adult patients with hemorrhagic MMD in the acute stage.

PATIENTS AND METHODS

Adult hemorrhagic MMD patients in the acute stage awere retrospectively analyzed. Both clinical and imaging data were collected. Unfavorable functional outcome at discharge was considered when modified Rankin Scale score ≥3. Multivariate logistic regression was used to investigate the prognostic factors in patients with hemorrhagic MMD in the acute stage.

RESULTS

A total of 107 patients were included in this study. Among these patients, 17 died and 59 had unfavorable functional outcome at 9.6 ± 7.8 days. In multivariate logistic regression, admission blood glucose (odds ratio (OR) = 1.457, 95% confidence interval (CI) 1.156-1.836, P = 0.001), midline shift >5 mm (OR = 24.268, 95%CI 4.324-136.191, P < 0.001), and subarachnoid hemorrhage (OR = 13.067, 95%CI 2.020-84.512, P = 0.007) were independently associated with death at discharge. Moreover, admission Glasgow Coma Scale (GCS) score (OR = 0.420, 95%CI 0.296-0.598, P < 0.001), midline shift >5 mm (OR = 6.685, 95%CI 1.226-36.455, P = 0.028), and intraparenchymal hemorrhage (OR = 4.790, 95%CI 1.184-19.381, P = 0.028) were independently associated with unfavorable functional outcome at discharge.

CONCLUSION

This study shows that admission blood glucose, midline shift >5 mm, and subarachnoid hemorrhage are independent predictors of short-term mortality in hemorrhagic MMD in the acute stage. In addition, admission GCS score, midline shift >5 mm, and intraparenchymal hemorrhage are independent predictors of short-term unfavorable functional outcome in hemorrhagic MMD in the acute stage.

Restoration of periventricular vasculature after direct bypass for moyamoya disease: intra-individual comparison

BACKGROUND

While periventricular anastomosis, a unique abnormal vasculature in moyamoya disease, has been studied in relation to intracranial hemorrhage, no study has addressed its change after bypass surgery. The authors sought to test whether direct bypass surgery could restore normal periventricular vasculature.

METHODS

Patients who had undergone direct bypass surgery for moyamoya disease at a single institution were eligible for the study. Baseline, postoperative, and follow-up magnetic resonance angiography (MRA) scans were scheduled before surgery, after the first surgery, and 3 to 6 months after contralateral second surgery, respectively. Sliding-thin-slab maximum-intensity-projection coronal MRA images of periventricular anastomoses were scored according to the three subtypes (lenticulostriate, thalamic, and choroidal anastomosis). Baseline and postoperative MRA images were compared to obtain a matched comparison of score changes in the surgical and nonsurgical hemispheres within individuals (intra-individual comparison).

RESULTS

Of 110 patients, 42 were identified for intra-individual comparisons. The periventricular anastomosis score decreased significantly in the surgical hemispheres (median, 2 versus 1; p < 0.001), whereas the score remained unchanged in the nonsurgical hemispheres (median, 2 versus 2; p = 0.57); the score change varied significantly between the surgical and nonsurgical hemispheres (p < 0.001). Of the 104 periventricular-anastomosis-positive hemispheres undergoing surgery, 47 (45.2%) were assessed as negative in the follow-up MRA. Among the subtypes, choroidal anastomosis was most likely to be assessed as negative (79.7% of positive hemispheres).

CONCLUSIONS

Periventricular vasculature can be restored after direct bypass. The likelihood of correction of choroidal anastomosis is a subject requiring further studies.

Meta-Analysis of Prognosis of Different Treatments for Symptomatic Moyamoya Disease

OBJECTIVE

The purpose of this study was to evaluate the efficacy of surgical revascularization versus conservative treatment and different surgical modalities, in order to provide evidence for the patient with moyamoya disease (MMD) to choose the appropriate treatment.

METHODS

We comprehensively searched PubMed, Embase, Web of Science, and the Cochrane Library for articles published regarding MMD treatment. If the I² value, which evaluated the heterogeneity, was <50%, a fixed-effect model was used; if not, a random effect model was applied.

RESULTS

Twenty-seven articles were included in the meta-analysis. The surgery group is more advantageous in reducing the risk of future stroke events than conservative treatment in MMD patients (odds ratio [OR] 0.26, 95% confidence interval [CI] 0.20-0.33, P < 0.001). In addition, the surgical group also had an advantage in terms of increased cerebral perfusion (OR 7.16, 95% CI 3.28-15.64, P < 0.001) and death due to rebleeding (OR 0.27, 95% CI 0.10-0.72, P < 0.01). Direct surgery showed a significant efficacy over indirect surgery (OR 2.03, 95% CI 1.32-3.13, P < 0.01). No obvious difference was found between the direct and indirect bypass subset (OR 0.76, 95% CI 0.51-1.14, P = 0.185). Angiographic results in patients undergoing direct bypass surgery are more pronounced (OR 0.20, 95% CI 0.06-0.67, P < 0.01).

CONCLUSIONS

In patients with symptomatic moyamoya disease, bypass surgery is more effective than conservative treatment to prevent future strokes. In surgical patients, direct bypass seems to reduce the risk of stroke more than an indirect bypass.

Intractable Medial Anastomotic Branches from the Lenticulostriate Artery Causing Recurrent Hemorrhages in Moyamoya Disease

BACKGROUND

Although superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis is a beneficial treatment for hemorrhagic moyamoya disease, indeterminate mechanisms can cause rebleeding even after successful bypass surgery. We describe a case with a prominent collateral from the lenticulostriate artery (LSA) causing multiple recurrent hemorrhages after successful STA-MCA anastomosis.

CASE DESCRIPTION

A 49-year-old Japanese woman with moyamoya disease was referred to our institution after suffering intracranial hemorrhage on 2 occasions. Angiography revealed multiple anastomotic vessels branching from a prominent LSA to connect medullary arteries in the periventricular area corresponding to the location of the hemorrhage. She underwent STA-MCA anastomoses and the bypass widely perfused the MCA territory; however, intracranial hemorrhage recurred in the same hemisphere. Angiography revealed sustained dilatation of the medial anastomotic branches from the LSA with de novo pseudoaneurysm, whereas the lateral branches showed shrinkage. Subsequent surgical treatment included direct bypass targeting the medial hemispheric surface in which the medial branches were distributed; marked shrinkage of the branches and disappearance of the aneurysm were obtained without infarct.

CONCLUSIONS

Lenticulostriate anastomotic branches distributed medially to the anterior cerebral artery territory should be given more attention as an intractable cause of hemorrhage after successful STA-MCA anastomosis. Although challenging, direct bypass targeting the area reached by collateral vessels could be considered an alternative treatment strategy for this pathologic condition.

Direct Bypass Surgery Vs. Combined Bypass Surgery for Hemorrhagic Moyamoya Disease: A Comparison of Angiographic Outcomes

Objective: Extracranial-intracranial bypass is currently recognized as the optimal treatment for hemorrhagic-type moyamoya disease (MMD) which reduces incidence of rebleeding. Recent studies have reported the advantage of combined bypass over direct bypass for the general MMD patients. However, the effect of direct bypass and combined bypass surgery specifically for hemorrhagic-type MMD had not been investigated yet. Methods: Hemorrhagic-type MMD patients who underwent direct and combined bypass surgery with complete clinical and radiological documentation from a multicenter cohort between 2009 and 2017 were retrospectively included. Surgical methods included superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis (direct bypass), combined STA-MCA bypass with encephalodurosynangiosis (EDS), and combined STA-MCA bypass with encephaloduroarteriosynangiosis (EDAS). Matsushima standard on follow-up catheter angiography was used to assess surgical outcome. Modified Rankin Scale, incidence of rebleeding and ischemia during follow-up were recorded. Rebleeding-free survival rates between direct and combined bypass were compared by Kaplan-Meier analysis. Results: Sixty eight hemorrhagic-onset MMD patients were included in this study, among which 71 hemispheres were treated with surgery (direct bypass: 17; bypass+EDS: 24; bypass+EDAS: 30). Forty six (64.8%) hemispheres had satisfactory revascularization (Matsushima level 2-3) and 26 (36.6%) had poor neoangiogenesis. Matsushima level was not significantly different between surgical groups (P = 0.258). Good neoangiogenesis from dural grafts was achieved in 26 (36.6%) hemispheres, and good neoangiogenesis from STA grafts was only seen in 4 (out of 30, 12.5%) hemispheres. Multivariate analysis showed bypass patency [P < 0.001, OR (95%CI): 13.41 (3.28-54.80)] and dural neoangiogenesis [P < 0.001, OR (95%CI): 13.18 (3.26-53.36)] both independently contributed to good angiographic outcome. During follow-up, incidences of rebleeding or ischemic events, and re-bleeding free survival rate were not significantly different between surgical groups (P = 0.433, P = 0.559, and P = 0.997). However, patients who underwent combined bypass surgery had significantly lower mRS at follow-up comparing to patients who underwent direct bypass (P = 0.006). Conclusion: Combined bypass surgery and direct bypass surgery offered similar revascularization for hemorrhagic MMD. Bypass patency and dural angiogenesis both contributed to revascularization independently. The potential of indirect bypass to grow new vessels in hemorrhagic-MMD patients was generally limited, but dural leaflets offered better neoangiogenesis than STA grafts and was therefore recommended for surgical revascularization of hemorrhagic MMD.

Moyamoya angiopathy: long-term follow-up study in a Finnish population

BACKGROUND AND PURPOSE

Moyamoya angiopathy (MMA) is a chronic cerebrovascular disorder predominantly starting in childhood or early adulthood and thus affects the whole lifetime. Little is known on MMAs long-term outcomes in European patients. We report long-term follow-up data on Finnish MMA patients.

METHODS

We included patients from our Helsinki University Hospital MMA database and arranged long-term follow-up visits for all the patients. This follow-up included a review of the medical records accumulated in due time, detailed neurological and neuropsychological evaluation, and outcome measures modified Rankin Scale (mRS) and Barthel Index (BI).

RESULTS

There were 61 MMA patients with a mean follow-up period of 9.5 years (SD 6.7 years; range 1.3-35.4 years; 581 patient-years). Only two patients had died and two-thirds (n = 40, 65.6%) had no new events during the follow-up period. Eight patients (13.1%) had an ischemic and five patients (8.2%) a hemorrhagic stroke during the follow-up. There were no differences between operated (n = 26) and conservatively (n = 35) treated groups regarding recurrent events or the outcome measured with mRS or BI. Finnish MMA patients reported significantly poorer physical and psychological health aspects of QOL when compared to the general Finnish population. Symptoms of low mood were found in 27 (56%) patients.

CONCLUSIONS

Finnish MMA patients have a benign and stable course with a ~3.5 % annual stroke risk. We found no differences in the clinical outcomes between the operated and conservative groups, however, the psychosocial well-being requires more attention in MMA patients.