Encephaloduroarteriosynangiosis Research Articles

Differential clinical outcomes following encephaloduroarteriosynangiosis in pediatric moyamoya disease presenting with epilepsy or ischemia.

The purpose of this study was to compare clinical outcomes and surgical results after encephaloduroarteriosynangiosis (EDAS) in pediatric patients with Moyamoya disease that manifested as either ischemia or epileptic seizures. We treated 23 children who underwent EDAS; we divided the patients into either ischemic or epileptic groups according to the individuals' clinical presentation. Group Ia included those who mainly presented with cerebral ischemia in the form of preoperative transient ischemic attacks (TIA), while Group Ib presented with ischemia in the form of irreversible neurologic deficits or proven cerebral infarcts. Group II included those who presented with epileptic seizures rather than cerebral ischemia. We compared the clinical outcomes and surgical results following EDAS in the three groups. We grouped the patients into three groups according to their main preoperative clinical symptoms (Group Ia n = 10, Group Ib n = 6, and Group II n = 7). Group II, the epileptic manifestation group, tended to show more favorable clinical outcomes compared to the ischemic manifestation group, especially the severe ischemic group. However, there were no significant differences in postoperative neuroimaging and hemodynamic assessments between the groups. EDAS is a safe and effective surgical technique that prevents epileptic seizures and shows more favorable clinical outcomes when used in patients with Moyamoya disease presenting with epileptic seizures compared to cerebral ischemia.

The Importance of Encephalo-Myo-Synangiosis in Surgical Revascularization Strategies for Moyamoya Disease in Children and Adults

The optimal surgical procedure (direct, indirect, or combined anastomosis) for management of moyamoya disease is still debated. We evaluated the outcome of our broad area revascularization protocol, the Tokyo Daigaku (The University of Tokyo) (TODAI) protocol, analyzing the relative importance of direct, indirect, and combination revascularization strategies to identify the optimal surgical protocol. The TODAI protocol was used to treat 65 patients with moyamoya disease (91 hemispheres, including 48 in 29 childhood cases collected during 1996-2012). The TODAI protocol combined direct superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis with indirect revascularization using encephalo-myo-synangiosis (EMS) forpatients ≥10 years old or indirect revascularization using encephalo-duro-arterio-synangiosis (EDAS) with EMS for patients ≤9 years old. Clinical outcome was evaluated retrospectively. Digital subtraction angiography was performed for postoperative evaluation of revascularization in 47 patients (62 hemispheres; 27 adults and 35 children). Based on the relative contribution of additional flow from each revascularization path, 4 revascularization patterns were established. The mean follow-up period was 90 months in children and 72 months in adults. Perioperative complications were seen in 4 of 48 operations in children and 1 of 43 operations in adults. Except for 1 child with recurrent transient ischemic attacks and 1 adult with intracerebral hemorrhage, the patients showed excellent clinical outcomes. Postoperative digital subtraction angiography evaluation showed that in STA-MCA anastomosis+ EMS cases (34 hemispheres; 25 adults and 9 children), STA-MCA anastomosis provided greater revascularization than EMS (STA-MCA anastomosis > EMS) in 7 hemispheres, the opposite was true (STA-MCA anastomosis < EMS) in 14 hemispheres, an equivalent contribution to revascularization (STA-MCA anastomosis ≈ EMS) was present in 12 hemispheres, and no functioning anastomosis was present in 1 hemisphere. In cases of EDAS+ EMS (28 hemispheres; 2 adults and 26 children), all hemispheres showed revascularization: EDAS was dominant to EMS (EDAS > EMS) in 1 hemisphere, the opposite (EMS > EDAS) was true in 14 hemispheres, and EDAS was equivalent to EMS (EDAS ≈ EMS) in 13 hemispheres. EMS plus direct or indirect anastomosis is an effective surgical procedure in adults and children. The TODAI protocol provided efficient revascularization and yielded excellent results in preventing strokes in patients with moyamoya disease with very few complications. EMS had a main role in revascularization in each of the combined techniques.

Research Progress of Moyamoya Disease in Children

During the onset of Moyamoya disease (MMD), progressive occlusion occurs at the end of the intracranial internal carotid artery, and compensatory net-like abnormal vessels develop in the skull base, generating the corresponding clinical symptoms. MMD can affect both children and adults, but MMD in pediatric patients exhibits distinct clinical features, and the treatment prognoses are different from adult patients. Children are the group at highest risk for MMD. In children, the disease mainly manifests as ischemia, while bleeding is the primary symptom in adults. The pathogenesis of MMD in children is still unknown, and some factors are distinct from those in adults. MMD in children could result in progressive, irreversible nerve functional impairment, and an earlier the onset corresponds to a worse prognosis. Therefore, active treatment at an early stage is highly recommended. The treatment methods for MMD in children mainly include indirect and direct surgeries. Indirect surgeries mainly include multiple burr-hole surgery (MBHS), encephalomyosynangiosis (EMS), and encephaloduroarteriosynangiosis (EDAS); direct surgeries mainly include intra- and extracranial vascular reconstructions that primarily consist of superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. Indirect surgery, as a treatment for MMD in children, has shown a certain level of efficacy. However, a standard treatment approach should combine both indirect and direct procedures. Compared to MMD in adults, the treatment and prognosis of MMD in children has higher clinical significance. If the treatment is adequate, a satisfactory outcome is often achieved.

Identification of a hemodynamic parameter for assessing treatment outcome of EDAS in Moyamoya disease

This work is a novel attempt to incorporate computational fluid dynamics (CFD) techniques in the analysis of hemodynamic parameters of Moyamoya disease (MMD). Highly prevalent in Asian countries, MMD is characterised by progressive occlusion of the intracranial Internal Carotid Arteries (ICA). We intend to identify a reliable hemodynamic parameter that can be used to gauge treatment outcome. This will aid surgeons in the perioperative management of MMD patients. We carried out CFD analysis on eight patients (5 female, 3 male) with MMD treated by EDAS (encephalo-duro-arterio-synangiosis) between 2011 and 2012. All the eight patients presented with haemorrhage, with subsequent 4–12 month follow-up done using Magnetic Resonance Angiography (MRA) to capture auto-remodelling. We calculated percentage change in flow rate and pressure drop indicator (ΡDI) across the Left and Right ICA. Pressure drop indicator (PDI) is defined as the difference of pressure reduction within the carotid arteries, measured at post-op and follow up, using patient specific inflow rates. The measured percentage flow change and pressure reduction showed an increase at follow up for improved patients (characterised by angiography according to the method of Matsushima), who did not develop any complications after surgery. The inverse was observed in patients who were clinically classified as no change and retrogressed (according to the method of Matsushima) cases post-operation. This elucidates that our findings have instituted a new parameter that may well play a critical role as an assistive clinical decision making tool in MMD.

Surgical outcomes following encephaloduroarteriosynangiosis in North American adults with moyamoya.

Moyamoya disease/syndrome (MMD/S) is a progressive, occlusive vasculopathy of the intracranial vasculature that leads to ischemic and hemorrhagic strokes. Significant debate exists regarding the role of indirect cerebrovascular bypass surgery in its management. The authors review their institution's experience with indirect bypass in the surgical management of patients with MMD/S. The authors conducted a retrospective review of patients with MMD/S who underwent encephaloduroarteriosynangiosis (EDAS), a form of indirect bypass, from 1996 to 2013. A total of 37 patients (52 hemispheres) underwent an EDAS procedure for MMD/S; 21 patients received revascularization of both hemispheres. Patients presented with the following: 49% with stroke, 35% with transient ischemic attack, 13% with hemorrhage, and 3% with seizure. The mean Suzuki grade was 3.46. The number of patients with a modified Rankin Scale score of 0-1 improved from 21 to 29 (p = 0.002) from the time of surgery to the time of last follow-up. The number of neurological events (i.e., transient ischemic attacks, strokes, and hemorrhages) decreased from a mean of 1.7 events per patient to 0.14 (p < 0.001). The mean length of follow-up was 32.8 months. This series demonstrates that EDAS is an effective procedure for MMD/S in a North American cohort of patients.

Delayed posterior circulation insufficiency in pediatric moyamoya disease.

Approximately 30% of patients with moyamoya disease (MMD) have presented with involvement of the posterior circulation, mainly the posterior cerebral artery (PCA). Diagnosis of delayed progression of PCA stenosis in MMD may be difficult due to the diversity in clinical features. The goal of this study was to evaluate pediatric MMD patients with delayed PCA involvement after completion of revascularization of the anterior circulation. Forty-one pediatric MMD patients who underwent revascularization of the PCA territory due to delayed posterior circulation insufficiency MMD from 2006 to 2011 were retrospectively reviewed. The average interval between the initial operation and the occipital artery (OA) procedure was 5.0 years. Common symptoms were headaches and transient visual symptoms. The decision to operate was made based on a combination of diagnostic tools. The results obtained with perfusion MRI, SPECT, MR angiography, and EEG supported posterior circulation insufficiency in 78, 41, 73, and 71% of patients, respectively. Encephaloduroarteriosynangiosis (EDAS) using the OA was performed in 15 patients, and 26 patients received multiple burr hole trephination of the occipital area. All patients showed clinical improvement. Clinicians should be aware of the possibility of delayed involvement of the PCA in pediatric MMD patients. The clinical decision regarding treatment should be based on a combination of symptomatology and the results obtained with various tools to assess whether the blood flow in the PCA territory is insufficient. Surgical treatment using indirect revascularization appears to be effective for patients with delayed PCA involvement.

External carotid stenting for symptomatic stenosis in a patient with patent EDAS for Moyamoya disease

BackgroundMoyamoya disease is characterized by progressive narrowing of the internal carotid artery (ICA). Symptomatic patients typically undergo cerebrovascular intervention via extracranial–intracranial (EC–IC) bypass, most often with the use of the...

The change of middle meningeal artery postoperation of encephalo-duro-arterio-synangiosis on patients with Moyamoya disease

Objective To summarize the changc of middle meningeal artery after of encephalo-duro-arteriosynangiosis(EDAS) on Moyamoya disease and argue the probably reason of the changing,Methods Retrospective analysis of the DSA image before and after operations of EDAS on 131 patients with Mdoyamoya disease.Results Operation of EDAS were performed on 249 hemispheres of 131 patients with Moyamoya disease.Connection with vessels on cerebral of middle meningeal artery was found on 54 hemispheres.After the proccdure,new connection was found on 139 hemispheres.We preformed super selection angiograph of superficial temporal artery and internal maxillary artery on 74 hemispheres,and new connection of them were fotund on 58 hemispheres.Conclusions The new connection of the stem and branches of middle meningeal artery with the vessels on brain tissues can be found after procedures of EDAS on patients with Moyamoya disease.The mechanism is not clear.The protection of middle meningeal artery is very important during the procedure. Key words: Moyamoya disease; Encephalo-duro-arterio-synangiosis; Middle meningeal artery

Abstract T MP30: Cerebral Arteriogenesis and Angiogenesis: Distinct Angioarchitecture of Innate and EDAS Collaterals in Intracranial Arterial Steno-Occlusive Disease

Introduction: Patients with ICASD form various degrees of collateralization. However, those collaterals fail over time contributing to symptom progression. Indirect revascularization via encephaloduroarteriosynangiosis (EDAS) establishes collateral flow through new vessels formed from external carotid branches in both moyamoya disease (MMD) and non-moyamoya (NM) ICASD. We hypothesize that the EDAS neovascularization differs in terms of angioarchitecture when compared to spontaneously formed collaterals in ICASD. Methods: We analyze pre and post-operative digital subtraction angiograms (DSA) of patients enrolled in a prospective trial of EDAS surgery using ImageJ software (http://imagej.nih.gov/ij). Angioarchitectural differences between innate and post-EDAS collaterals were evaluated by comparing their branching angioscore (BA) and artery tortuosity index (ATI). Results: Images from 26 patients, ages 4 to 84 (mean: 37 SD+/-19.5) were evaluated. Patients included 13 MMD and 13 NM-ICASD. Postoperative mean DSA time was 14 months. Post-EDAS collaterals had significantly higher BA and lower ATI than innate collaterals (BA: 9.8 vs. 5.5 and ATI 110 vs. 167 [p&lt;0.001] respectively). Subgroup analyses for patients with MMD and NM-MMD demonstrated the same pattern with higher BA for post-EDAS collaterals and lower ATI for innate collaterals (MMD: BA: 9.6 vs. 5.2, and ATI 107.7 vs.176.5, NM-ICASD: BA: 9.9 vs. 5.8, and ATI: 153.7 vs.115.4 p≤0.01). Type of ICASD, age, or time after angiography did not affect the indexes. Conclusions: Collaterals formed after EDAS differ in angioarchitecture to innate collaterals in MMD and NM-ICASD. Morphological differences are consistent with two distinct mechanisms of vessel formation: innate collaterals formed by arteriogenesis display high tortuosity and low branching as expected by a shear stress process acting on pre-existing conduits. Conversely, post-EDAS collaterals have higher branching and lower tortuosity as expected in a process of angiogenesis in which collaterals form through sprouting and splitting from the donor vessels.

Abstract T P90: Characterization of Inflammatory Cells after EDAS Surgery in Patients with Intracranial Arterial Stenosis

Introduction: Indirect revascularization via encephaloduroarteriosynangiosis (EDAS) establishes collateral flow through new vessels formed from external carotid branches in patients with moyamoya disease and intracranial arterial stenosis (IAS) of non-moyamoya origin. A better understanding of the process of neovascularization is key to improve the potential therapeutic effects of these techniques. To gain a more in-depth understanding on the mechanisms behind the pro-angiogenic effects, we performed detailed evaluation of cellular changes in circulating monocytes. Methods and Results: Dynamics in inflammatory cell were assessed by cell surface marker analysis by flow cytometry of blood from patients at 24, 48 and 72 hours and compared to baseline control (pre-operative) levels from the same patient. While increase in CD45+ cells was noted at 24hrs in all patients, a particularly impressive elevation in the percentage of CD11b/Gr1 positive cells was found in patients at 48 and 72hrs post-surgery. Although CD11b suggested a monocytic population, these cells were F480 low/negative indicating a shift in the differentiation of monocytes or exit of a different population of inflammatory cells from the bone marrow. Conclusions: Our findings are in accordance with recent publications suggesting a pro-angiogenic role of macrophages during vascular expansion and repair. The findings are consistent with the concept that CD11b/Gr1 cells might constitute an important subset of monocyte/macrophages poised to mediate vascular repair upon stroke and could represent a clinically valuable tool.

Encephaloduroarteriosynangiosis (EDAS) For Patients With Sickle Cell Disease

IntroductionRegular blood transfusion therapy is the standard care for secondary prevention of strokes in sickle cell disease (SCD). Despite regular blood transfusion therapy approximately 45% of the children with strokes will have progressive neurological disease (overt strokes or new silent cerebral infarcts) with an incidence of overt strokes of 3.2 events/100 patient-years (95% confidence interval, 1.3-6.5) (Hulbert, Blood 2011). Limited additional therapeutic options exist for these patients. Encephaloduroarteriosynangiosis (EDAS) is a neurosurgical procedure to improve cerebral blood flow by transposing scalp arteries onto the surface of the brain. Five previously published series reported a total of 41 EDAS or indirect revascularization procedures on patients with SCD aged 3-22 yrs. Three of 41 patients (7%) had a stroke at 24 hours, 5 days and three weeks following EDAS/indirect revascularization. Additionally, one patient developed TIA 12 months later, two patients developed intracranial hemorrhage, and one patient died from a pulmonary embolus during an episode of acute chest syndrome 48 months post-EDAS. To date, the incidence of complications and efficacy of EDAS procedure in stroke prevention has not been well established. ObjectivesTo examine the incidence of overt stroke pre and post-EDAS for patients on chronic transfusion. MethodsWe studied a pediatric cohort with history of HbSS and SB0 thalassemia on chronic transfusion for CNS injury who underwent EDAS at the University of Alabama at Birmingham. The incidence of overt stroke pre- and post-EDAS was reviewed. All pre-transfusion hemoglobin and percent Hemoglobin S levels were recorded from the time of their first recorded abnormal MRI. To determine the acute complications of EDAS, we reviewed the peri-operative hospital records at the time of EDAS, post-EDAS emergency room visits and chronic transfusion clinic visits post EDAS. ResultsA total of 13 patients on chronic transfusion for secondary stroke prevention underwent 17 EDAS procedures for recurrent stroke, progressive vascular disease, or neurologic change including psychosis and decline in neuropsychometric scores. The mean time to EDAS was 80 months (median 56) from their first abnormal MRI in the medical records. The patients' mean pre-transfusion hemoglobin level was 9.4 g/dL and mean HbS was 29.5%. All participants (n=13) maintained a mean pre-transfusion HbS < 40%; 62% (8/13) participants maintained a mean HbS <30% (two patients with elevated HbS were transitioned to hydroxyurea as part of a clinical trial). Prior to EDAS, three patients had a new overt stroke during 81 patient years.(3.7 strokes per 100 pt yrs) One of 17 EDAS procedures was complicated by an acute stroke one month after the procedure. No additional strokes occurred in these patients during 34 patient years.(3 strokes per 100 pt yrs) One child developed a chronic subdural hematoma one month post-EDAS requiring burr hole drainage; this patient had a complete recovery. ConclusionThis case series represents the largest cohort of EDAS procedures for children with SCD, and in combination with the literature, suggests that patients with progressive CNS disease may benefit from EDAS. A multicenter retrospective case series should be completed to identify risk factors for progression status post an EDAS procedure followed by a clinical trial to determine the effectiveness of the procedure versus regular blood transfusion therapy. Disclosures:No relevant conflicts of interest to declare.

Combined Direct and Indirect Bypass for Moyamoya

The optimal revascularization strategy for symptomatic adult moyamoya remains controversial. Whereas direct bypass offers immediate revascularization, indirect bypass can effectively induce collaterals over time. Using angiography and quantitative magnetic resonance angiography, we examined the relative contributions of direct and indirect bypass in moyamoya patients after combined direct superficial temporal artery-to-middle cerebral artery (STA-MCA) bypass and indirect encephaloduroarteriosynangiosis (EDAS). A retrospective review of moyamoya patients undergoing combined STA-MCA bypass and EDAS was conducted, excluding pediatric patients and hemorrhagic presentation. Patients with quantitative magnetic resonance angiography measurements of the direct bypass immediately and > 6 months postoperatively were included. Angiographic follow-up, when available, was used to assess EDAS collaterals at similar time intervals. Of 16 hemispheres in 13 patients, 11 (69%) demonstrated a significant (> 50%) decline in direct bypass flow at > 6 months compared with baseline, averaging a drop from 99 ± 35 to 12 ± 7 mL/min. Conversely, angiography in these hemispheres demonstrated prominent indirect collaterals, in concert with shrinkage of the STA graft. Decline in flow was apparent at a median of 9 months but was evident as early as 2 to 3 months. In this small cohort, a reciprocal relationship between direct STA bypass flow and indirect EDAS collaterals frequently occurred. This substantiates the notion that combined direct/indirect bypass can provide temporally complementary revascularization.

A case of graves' disease diagnosed in the course of bilateral carotid artery stenoses (moyamoya disease); a case report and review of the literature.

A 14-year-old boy was admitted to our hospital after being diagnosed at a local clinic with bilateral carotid artery stenoses (Moyamoya disease) and mild thyrotoxicosis. A blood examination showed suppressed TSH and elevated triiodothyronine and thyroxine levels; however, he was negative for anti-thyrotropin receptor antibody (TRAB) and thyroid stimulating antibody (TSAB). Concern about a possible thyroid crisis led us to administer thiamazole (MMI) and potassium iodide (KI), following which encephalo-duro-arterio-synangiosis (EDAS) of the left side was performed successfully. After about 1 mo, he became positive for TRAB and TSAB. He was thought to have Graves' disease and Moyamoya disease coincidentally. Several factors are considered to be involved in the coincidental onset of these two diseases.

Coexistence of moyamoya and Graves’ diseases: The clinical characteristics and treatment effects of 21 Chinese patients

ObjectiveTo investigate the clinical features, pathogenesis and treatment effect of patients who had moyamoya disease (MMD) concurrent with Graves’ disease (GD). Patients and methodsRetrospective analysis of the examination and treatment results of the MMD patients with GD from January 2003 to April 2012 treated by our teamwork. ResultsThere were 1493 MMD patients included in this retrospective study. Among them, there were 16 female and 5 male MMD patients coexisted with Graves’ diseases, and 15 of them were adult patients. Bilateral and unilateral lesions were observed in 18 and 3 cases, respectively. 19 patients show cerebral infarction. 18 patients manifested MMD symptoms when they were in a hyperthyroid state. 17 patients received encephaloduroarteriosynangiosis (EDAS) surgery after antithyroid treatment. There were 20 patients completed 2 and 77 months follow-up. 17 patients had good recovery and the other 3 patients had mild or moderate disability. Post-operative DSA achieved in 8 patients examinations showed good collateral circulation to the brain from superficial temporal artery (STA). ConclusionMoyamoya disease complicating GD is mostly occurred in adult female patients. Their clinical symptoms are mainly ischemic lesions and usually occur during the state of hyperthyroidism. The pathogenesis of moyamoya disease complicating GD may be associated with a variety of genetic and immune factors. Surgical treatment can establish effective collateral circulation and reduce the risk of recurrence of stroke.

Abstract TP143: Early Angiographic Neovascularization Response to EDAS Surgery in Adults with Intracranial Arterial Stenosis

Introduction: Significant neovascularization following indirect revascularization procedures, such as encephaloduroarteriosynangiosis (EDAS), has traditionally been considered to develop slowly over time. However, a recent study of angiography following indirect revascularization procedures demonstrated early signs of revascularization as early as 4 days following surgery. While we have previously published demonstration of robust revascularization at 6 months and later following surgery, here we present a subset of patients, all with non-moyamoya intracranial arterial stenosis (IAS), with earlier angiographic evaluation following EDAS. Methods: We retrospectively reviewed charts of adult patients who have undergone EDAS for non-moyamoya IAS. These early angiograms were evaluated for signs of revascularization and graded according to the scale presented by Perren et al (1, no sign of neoangiogenesis; 2, one-to-four new transcortical vessels; 3, &gt; four new transcortical vessels). Results: Ten patients (mean age 43 years, 8 females) were found with follow-up cerebral angiography within 6 months of surgery (1 each at 1, 2 &amp; 3 mo, 2 at 1.5 mo, 3 at 5 mo, and 4 at 6 mo). All angiograms demonstrated neovascularity, regardless of underlying diagnosis, including scores of 3 (extensive neoangiogenesis) in 80% of cases as early as 1.5 months after surgery. Two patients had grade 2 at 1 &amp; 2 months. Clinically, all patients’ ischemic symptomatology has resolved. Six patients have had no symptoms since surgery while 4 patients had transient episodes consistent with ischemia (TIA) that all resolved by 2 weeks post-operatively (3 at 1 week and 1 at 2 weeks). No patient suffered stroke following EDAS. Conclusion: This series adds to the growing evidence that indirect revascularization procedures can lead to significant neovascularity in a shorter time frame than previously expected in adult patients, including those with non-moyamoya IAS. Further study is required to better define the time course of neoangiogenesis and to evaluate angiogenic mechanisms that contribute to the success of this procedure.

A Case of Graves’ Disease Diagnosed in the Course of Bilateral Carotid Artery Stenoses (Moyamoya Disease); A Case Report and Review of the Literature

A 14-year-old boy was admitted to our hospital after being diagnosed at a local clinic with bilateral carotid artery stenoses (Moyamoya disease) and mild thyrotoxicosis. A blood examination showed suppressed TSH and elevated triiodothyronine and thyroxine levels; however, he was negative for anti-thyrotropin receptor antibody (TRAB) and thyroid stimulating antibody (TSAB). Concern about a possible thyroid crisis led us to administer thiamazole (MMI) and potassium iodide (KI), following which encephalo-duro-arterio-synangiosis (EDAS) of the left side was performed successfully. After about 1 mo, he became positive for TRAB and TSAB. He was thought to have Graves’ disease and Moyamoya disease coincidentally. Several factors are considered to be involved in the coincidental onset of these two diseases.

Clinical Features, Surgical Treatment and Long-Term Outcome in Adult Patients with Moyamoya Disease in China

Background: Moyamoya disease (MMD) develops mostly in Asian countries including Japan, Korea, mainland China and Taiwan. However, there are few detailed demographic and clinical data about Chinese patients with MMD. Currently, the most effective treatment in adult patients with MMD is unknown. There have only been a few small case series reporting on encephaloduroarteriosynangiosis (EDAS) in an adult population. Here we describe the clinical features, surgical treatment and long-term outcome of adults with MMD treated at a single institution in China. Methods: Our cohort included 470 adult patients with MMD. The demographic and clinical characteristics were obtained by retrospective chart review and long-term outcome was evaluated using the stroke status. The modified Rankin Scale (mRS) was used to determine the neurological functional outcome. Univariate and multivariate logistic regression analyses were performed to determine risk factors for postoperative morbidity and functional outcome. The risk of subsequent stroke was determined using the Kaplan-Meier method and Cox regression was used to determine risk factors for postoperative or subsequent strokes. Results: The median age for the onset of symptoms was 36.8 (range, 18–59) years. The ratio of female to male patients was 1:1 (231/239). Familial occurrence of MMD was 2.3%. The most common initial symptom was a cerebral ischemic event. The incidence of postoperative ischemic events or hemorrhage was 5.9% (9.8% of patients). Older age at symptom onset, posterior cerebral artery (PCA) involvement and the presence of transient ischemic attack (TIA) were identified as predictors of adverse postoperative events. The Kaplan-Meier estimate stroke risk was 10.1% in the first 2 years, and the 5-year Kaplan-Meier risk of stroke was 13% after surgery for all patients treated with surgical revascularization. Older age at symptom onset, PCA involvement and the presence of TIA were identified as predictors of postoperative or subsequent strokes. Overall, 73.2% of patients had an independent life with no significant disability, with the strongest predictor being the preoperative mRS score. Conclusion: Clinical characteristics of adult MMD in China are different from those in other Asian countries. EDAS in adult patients with MMD carries a low risk, is effective at preventing future ischemic events and improves quality of life.

Bifrontal encephalogaleosynangiosis for children with moyamoya disease

Several operative techniques have been reported to increase the cerebral blood flow (CBF) of the anterior cerebral artery (ACA) territory in patients with moyamoya disease. However, the optimal procedure has not yet been determined. This study compared the efficacy of performing bifrontal encephalogaleosynangiosis (EGS) using a craniotomy with performing EGS using bur holes. The authors retrospectively analyzed surgical results of pediatric patients with moyamoya disease treated using encephaloduroarteriosynangiosis (EDAS) and bifrontal EGS with a craniotomy, or EGS with bur holes, for the purpose of improving the ischemia of the ACA territory. Patients' demographic data, clinical presentations, surgical therapies, and clinical outcomes were reviewed. Nine patients underwent EDAS with bifrontal EGS using a craniotomy. Three patients underwent EDAS with EGS using bur holes for 5 cerebral hemispheres (1 bur hole in 2 hemispheres, 2 bur holes in 2 hemispheres, and 3 bur holes in 1 hemisphere). The mean follow-up period was 46.8 months (range 7-96 months). Preoperative symptoms improved in all patients in each group. The collateral circulation in the ACA territory made by EGS was divided into 3 groups according to postoperative angiography results: Group A (revascularization of more than two-thirds of the ACA territory), Group B (revascularization between one-third and two-thirds), and Group C (revascularization less than one-third). Of 5 hemispheres treated with EGS using bur holes, 1 was evaluated as Group B and 4 as Group C. Of 18 hemispheres treated with bifrontal EGS using a craniotomy, 8 were evaluated as Group A, 7 as Group B, and 3 as Group C. The patients who underwent bifrontal EGS using a craniotomy showed significantly better revascularization than those who underwent EGS using bur holes (p = 0.0065). Cerebral blood flow in the ACA territory improved in 13 (92.9%) of 14 hemispheres in patients treated with bifrontal EGS. In contrast, only 3 (60%) of 5 hemispheres demonstrated an increase of CBF in patients treated with EGS using bur holes. A trend was demonstrated for better improvement with bifrontal EGS (p = 0.08). Encephaloduroarteriosynangiosis with bifrontal EGS using a craniotomy demonstrated better revascularization and improvement of CBF in the ACA territory than with EGS using bur holes. Bifrontal EGS using a craniotomy is considered to be a simple, safe, and effective surgical procedure for improvement of the ischemia of the ACA territory in pediatric patients with moyamoya disease.

Indirect revascularization for nonmoyamoya intracranial arterial stenoses: clinical and angiographic outcomes

Symptomatic intracranial arterial stenoses have a high rate of recurrent stroke despite medical and endovascular treatments. The authors present clinical and angiographic quantitative outcomes of indirect revascularization for patients with symptomatic intracranial stenosis. Patients treated for symptomatic intracranial arterial stenosis by indirect revascularization were included. The patient population comprised those in whom medical management had failed and for whom endovascular therapy was unsuitable or had failed. Patients underwent encephaloduroarteriosynangiosis (EDAS) with or without bur holes. Preoperative and postoperative angiograms were evaluated for change in caliber of extracranial blood vessels (superficial temporal artery [STA] and middle meningeal artery [MMA]) and for evidence of neovascularization. Thirteen patients underwent EDAS. Ischemic symptoms ceased within the follow-up period in all patients, returning in a delayed fashion in only 2. No other patients had recurrent TIAs or strokes after the initial postoperative period. Donor blood vessels increased in size relative to preoperative sizes in all but 1 case (average increase of 52% for proximal STA [p=0.01], 74% for midpoint of STA [p=0.01], and 84% for the MMA [p=0.02]). In addition, 8 of 11 patients demonstrated direct spontaneous anastomoses from extracranial to middle cerebral artery branches, and all patients demonstrated angiographic evidence of vascular blush and/or new branches from the STA and/or MMA. Indirect revascularization appears to be a safe and effective method to improve blood flow to ischemic brain due to intracranial arterial stenosis. Neovascularization and enlargement of the branches of the ECA were observed in all patients and correlated with improvement in ischemic symptoms. Indirect revascularization is an option for patients in whom medical therapy has failed and who are not suitable for endovascular treatment.

Quantitative Angiographic Comparison With the OSIRIS Program Between the Direct and Indirect Revascularization Modalities in Adult Moyamoya Disease

Up-to-date, quantitative angiographic measurement of revascularization extent after bypass surgery has not been reported. To measure the extent of angiographic revascularization quantitatively 6 months postoperatively with the OSIRIS program (University Hospital of Geneva, version 3.1). A total of 75 bypass procedures were performed in 65 consecutive adult moyamoya disease patients, and 71 bypass surgeries in 61 adult moyamoya disease patients were studied 6 months postoperatively with angiography. We performed 5 different types of bypass surgeries: encephaloduroarteriosynangiosis (EDAS), superficial temporal artery-middle cerebral artery anastomosis (SMA), SMA with encephalomyosynangiosis (EMS), SMA with EDAS, and SMA with encephaloduroarteriomyosynangiosis (EDAMS). We also investigated single-photon emission computed tomography (SPECT) results after 6 months postoperatively and compared the angiographic revascularization extent with the SPECT results. The mean values for the extent of revascularization among 5 different bypass surgeries were as follows: 32.4% for EDAS only, 57.4% for SMA only, 58.4% for SMA with EMS, 66.1% for SMA with EDAS, and 70.8% for SMA with EDAMS. There was a statistically significant difference in the extent of revascularization among the 5 surgical modalities (P = .000) and between the EDAS-only group and various SMA groups (P = .000). Statistical analysis between angiographic revascularization extent and SPECT results demonstrated significant statistical correlation (P = .000). The extent of angiographic revascularization in adult moyamoya disease patients was highest in the SMA with EDAMS group and lowest in the EDAS-only group. In addition, angiographic revascularization extent was well correlated with the change in SPECT.