Long-term results of surgically treated moyamoya disease

Clinical Characteristics of Immediate Contralateral Ischemia Subsequent to Revascularization for Moyamoya Disease

BACKGROUND

Moyamoya disease is a bilateral steno-occlusive disease involving the cerebral vasculature. While some patients are affected by procedure-related ipsilateral ischemia, ischemic complications contralateral to the revascularization are rarely observed.

METHODS

We retrospectively investigated 135 hemispheres (103 patients) that underwent revascularization in our institution between April 2006 and September 2022. Revascularization surgery comprised single superficial temporal artery-middle cerebral artery anastomosis and encephalo-myo-synangiosis. Certain patients aged under 10 years underwent indirect revascularization. Bilateral revascularization was performed with an interval of >3 months. Medical records and neuroimages were reviewed, and patients with contralateral ischemic complications were identified. Some cases underwent genetic analysis.

RESULTS

The mean age was 34.5 (range: 5-71) years, and 95 cases (70.4%) were in women. Of the 102 cases examined for the RNF213 c.14429 G > A (p.Arg4810Lys) variant, 33 (32.4%) and 69 (67.6%) showed the GG and GA genotype, respectively. Three cases (2.2%, all female, age range 44-71 years) were complicated with contralateral infarction. The infarcted area distributions of the 2 cases with RNF213 c.14429 G > A variant were patchy and peripheral. The other case showed on magnetic resonance imaging (MRI) angiography total occlusion of the internal carotid artery where patency had been confirmed preoperatively.

CONCLUSIONS

Contralateral ischemia after revascularization occurred in 2.2% of cases. We classified them into peripheral and central types: peripheral type, an infarction owing to hemodynamic insufficiency or intracranial blood flow redistribution; central type, total occlusion of the contralateral internal carotid artery. Intensive preoperative management can minimize the risk of peripheral types, and neurosurgeons should beware of severe central types.

Post-Surgical Cognitive Outcomes of Moyamoya Disease: A Systematic Review

BACKGROUND

Moyamoya disease (MMD) is an occlusive arteriopathy leading to stroke. Progressive if left untreated, revascularization surgery has become the mainstay of treatment. Although clinical and radiographic outcomes of MMD after intervention are well-characterized, cognitive outcomes in pediatric patients remain unclear. We aimed to examine postoperative cognitive outcomes in children with MMD, examine factors associated with cognitive changes after intervention, and define the effect of revascularization surgery on cognitive outcomes.

METHODS

A systematic review was conducted following PRISMA guidelines searching PubMed, Embase, and Scopus databases. Articles met inclusion criteria if they studied pediatric patients undergoing revascularization surgery for MMD and examined cognitive outcomes either qualitatively or quantitatively. All data extracted from included articles was examined descriptively.

RESULTS

Of 1091 resultant articles, 12 articles containing 446 patients were included. Surgery was associated with maintained or improved full scale intellectual quotient (IQ), performance IQ, perceptual IQ, memory quotient and verbal memory. However, 70% of patients had impaired cognitive function, with associated poor school performance. Improvements in cognition were associated with increased cerebral blood flow, particularly to the middle cerebral artery, due to the development of collaterals. Female sex, shorter duration from symptom onset to surgery, and surgery after age 7 were predictive of cognitive improvement. Completed ischemic stroke prior to surgery was associated with poorer cognitive outcomes.

CONCLUSIONS

Although children with MMD have improved cognitive outcomes following revascularization overall, a distinct subset experience cognitive impairment. Consideration of patient-specific and treatment-related factors is important to enable proper risk stratification and inform management approaches.

Response of internal carotid artery blood flow velocity to fluid challenge under general anesthesia in pediatric patients with moyamoya disease: A prospective observational study

BACKGROUND

Maintaining cerebral blood flow is important in intraoperative management of moyamoya disease patients.

AIMS

To access changes in the carotid artery blood flow velocity in response to fluid challenge, blood pressure, and cardiac output under general anesthesia in pediatric patients with moyamoya disease.

METHODS

This observational study included pediatric patients with moyamoya disease undergoing general anesthesia for encephaloduroarteriosynangiosis. Each patient underwent an ultrasound assessment thrice as follows: after anesthetic induction (T1), after fluid challenge (10 ml/kg, T2), and at the end of surgery (T3). The primary outcome was the change in the internal carotid artery blood flow velocity after fluid challenge and was assessed using a paired t-test. The secondary outcomes comprised changes in the internal, external, and common carotid artery blood flow peak velocities after fluid challenge and the factors influencing these changes.

RESULTS

We enrolled and analyzed 30 patients with a mean age of 7.2 years. After fluid challenge, the systolic (p = .003) and mean blood pressure (p = .017), stroke volume index (p = .008), and cardiac index (p = .140) were higher than those at T1. However, both internal carotid artery blood flow velocities did not change after fluid challenge (p = .798, mean difference and 95% confidence interval [CI], -1.1 and -10.3 to 8.0 for right, p = .164, mean difference and 95% CI, -5.2 and -12.7 to 2.2 for left). The internal carotid artery blood flow velocity was correlated with the cardiac index, stroke volume index, and mean and diastolic blood pressure, with low significance.

CONCLUSIONS

The internal carotid artery blood flow velocity did not increase in pediatric patients with moyamoya disease under general anesthesia, despite fluid challenge and corresponding changes in the blood pressure and cardiac output. Intraoperative hemodynamic management to improve the cerebral blood flow in these patients requires further investigation.

The Value of Preoperative Phase-Contrast MRI in Predicting the Clinical Outcome of Moyamoya Disease after Encephalo-Duro-Arterial Synangiosis Surgery

BACKGROUND AND PURPOSE

In patients with Moyamoya disease, the relationship between preoperative hemodynamic status and prognosis after encephalo-duro-arterial synangiosis (EDAS) surgery was unclear. We aimed to explore the value of the preoperative hemodynamic status acquired by cine phase-contrast MR imaging in predicting collateral formation and clinical outcomes after EDAS surgery in patients with Moyamoya disease.

MATERIALS AND METHODS

Participants with Moyamoya disease were prospectively recruited and underwent preoperative phase-contrast MR imaging. All participants were classified into good and poor groups according to the collateral formation after EDAS surgery. On the basis of the change in the mRS system, participants were classified into the improved mRS group and the poor response group. Hemodynamic status including mean velocity, peak velocity, and blood volume flow of the superficial temporal artery was compared between groups. Logistic regression was performed to relate the phase-contrast MR imaging parameters to collateral formation and clinical outcomes.

RESULTS

A total of 45 patients with Moyamoya disease with unilateral EDAS surgery were finally included. Mean velocity, peak velocity, and blood volume flow of the ipsilateral superficial temporal artery were significantly greater in patients with good collateral formation compared with those with poor collateral formation (P = .011, .004, and .013, respectively). The mean velocity, peak velocity, and blood volume flow were independently associated with postoperative collateral formation after adjusting for confounding factors. Furthermore, the peak velocity of the ipsilateral superficial temporal artery was also significantly associated with improvement of the mRS score.

CONCLUSIONS

Good hemodynamic status of the ipsilateral superficial temporal artery as a donor artery evaluated by phase-contrast MR imaging was significantly associated with better collateral formation and improved mRS after EDAS surgery in patients with Moyamoya disease.

Short- and long-term outcomes of moyamoya patients post-revascularization

OBJECTIVE

The post-bypass stroke risk factors and long-term outcomes of moyamoya patients are not well documented. Therefore, the authors studied 30-day stroke risks and patients’ long-term physical, functional, and social well-being.

METHODS

This was a single-institution combined moyamoya disease (MMD) database interrogation and questionnaire study. From 1991 to 2014, 1250 revascularization procedures (1118 direct bypasses, 132 indirect bypasses) were performed in 769 patients. Completed questionnaires were received from and available for analysis on 391 patients, and 6-month follow-up data were available for 96.4% (741/769) of the patients.

RESULTS

The patients consisted of 548 females and 221 males, with a mean age of 32 years (range 1–69 years). Three hundred fifty-eight bypasses were performed in 205 pediatric patients (73% direct bypasses), and 892 revascularizations were performed in 564 adults (96% direct bypasses). Fifty-two patients (6.8%) developed major strokes with a worsening modified Rankin Scale (mRS) score within 30 days postoperatively. The 30-day major stroke risk was 5.3% (41/769) and 2.6% (12/467) after the first and second bypasses, respectively. Logistic regression analysis revealed that older age, modified MRI (mMRI) score, and hemodynamic reserve (HDR) score are clearly associated with higher postoperative stroke risks. Over a mean follow-up of 7.3 years (range 0.5–26 years), the long-term stroke risk among 741 patients was 0.6% per patient-year; 75% of these patients had excellent outcomes (mRS score 0–1). The long-term outcome questionnaire study showed that 84% (234/277) of patients reported resolution or improvement in their preoperative headache, 83% (325/391) remained employed or in school, and 87% (303/348) were self-caring.

CONCLUSIONS

In this large, single-center surgical series, most of the adult and pediatric patients had direct revascularization, with a 4.2% per-bypass-procedure (6.8% per patient) 30-day major stroke risk and a 0.6% per-patient-year long-term stroke risk. The authors identified various risk factors that are highly correlated with postoperative morbidity (age, mMRI score, and HDR score) and are involved in ongoing work to develop the predictive modeling for future patient selection and treatment.

Characterizing the neurocognitive profiles of children with moyamoya disease using the Das Naglieri cognitive assessment system

Although cognitive impairment is well-documented in children with moyamoya disease (MMD), selective decline in specific neurocognitive domains remains controversial. The purpose of this study was to characterize the neurocognitive profile of children with MMD using the Das Naglieri Cognitive Assessment System (CAS) and the Wechsler Intelligence Scale for Children, Fourth Edition (WISC-IV). We analyzed the neurocognitive data of 30 children (median age, 7 years) with MMD who were assessed with the CAS and the WISC-IV before surgery. We focused on the comparison of standard scores and intraindividual differences across domains. The CAS scores significantly varied across four measures (standard scores, p < 0.001; intraindividual differences, p < 0.001). Post-hoc analyses revealed that the standard scores and intraindividual differences for successive processing were significantly lower than those for planning and attention. The WISC-IV scores did not significantly vary among the four measures, although the working memory index was the lowest among the four measures. The within-individual weakness in successive processing, a form of working memory function, may be a distinct characteristic of children with MMD. The CAS may be more sensitive than the WISC-IV for detecting this selective neurocognitive weakness in children with MMD.

Predictors of neoangiogenesis after indirect revascularization in moyamoya disease: a multicenter retrospective study

OBJECTIVE

The effect of indirect revascularization to improve cerebral perfusion for moyamoya disease (MMD) is based on ingrowth of new vessels into the cortical brain. Preoperative indicators for neoangiogenesis would be helpful to the selection of appropriate procedures for MMD patients but have not yet been investigated. Our study aimed to identify potential predictors for neovascularization after indirect bypass surgery.

METHODS

The authors reviewed consecutive cases with complete clinical and radiological documentation of patients who had undergone surgery between December 2010 and January 2018. Patients who were treated with indirect bypass surgery were included. Cerebrovascular characteristics were evaluated by catheter angiography. Neoangiogenesis after indirect bypass was determined as "good" or "poor" based on the Matsushima standard. Univariate and multivariate analyses were performed to identify predictors for neoangiogenesis after indirect bypass. Subgroup analyses by onset type and surgical type were carried out to identify specific predictors for different populations.

RESULTS

In total, 231 hemispheres of 209 patients (mean ± SD age 23.06 ± 15.09 years, range 3-61 years) were retrospectively included. In 146 (63.2%) hemispheres, good neoangiogenesis was observed after indirect revascularization. Multivariate analysis showed that the status of ICA moyamoya vessels (p < 0.001, OR [95% CI] 3.242 [2.007-5.236]) is a predictor of favorable neoangiogenesis after indirect bypass surgery, whereas hemorrhagic onset (p < 0.001, OR [95% CI] 0.138 [0.054-0.353]) is a risk factor for poor neoangiogenesis. In addition, younger age was significantly associated with good neovascularization in patients with hemorrhagic onset (p = 0.027, OR [95% CI] 0.893 [0.808-0.987]), whereas age was not a significant predictor for neovascularization in non-hemorrhagic-onset patients (p = 0.955). Hemispheres with good revascularization had lower incidence of rebleeding, lower modified Rankin Scale scores, and more improvement of symptoms during long-term follow-up (p = 0.026, 0.006, and 0.013, respectively).

CONCLUSIONS

Hemorrhagic onset predicts poor neovascularization after indirect bypass surgery for MMD patients. Abundant ICA moyamoya vessels indicate good neoangiogenesis after indirect bypass and vice versa, whereas absent ICA moyamoya vessels predict poor revascularization. Good neovascularization was associated with better long-term outcome. Future studies are needed to further address this issue and clarify the underlying pathophysiological mechanisms.

Contralateral acute vascular occlusion following revascularization surgery for moyamoya disease

OBJECTIVE

Revascularization surgery is a safe and effective surgical treatment for symptomatic moyamoya disease (MMD) and has been shown to reduce the frequency of future ischemic events and improve quality of life in affected patients. The authors sought to investigate the occurrence of acute perioperative occlusion of the contralateral internal carotid artery (ICA) with contralateral stroke following revascularization surgery, a rare complication that has not been previously reported.

METHODS

This study is a retrospective review of a prospective database of a single surgeon's series of revascularization operations in patients with MMD. From 1991 to 2016, 1446 bypasses were performed in 905 patients, 89.6% of which involved direct anastomosis of the superficial temporal artery (STA) to a distal branch of the middle cerebral artery (MCA). Demographic, surgical, and radiographic data were collected prospectively in all treated patients.

RESULTS

Symptomatic contralateral hemispheric infarcts occurred during the postoperative period in 34 cases (2.4%). Digital subtraction angiography (DSA) was performed in each of these patients. In 8 cases (0.6%), DSA during the immediate postoperative period revealed associated new occlusion of the contralateral ICA. In each of these cases, revascularization surgery involved direct anastomosis of the STA to an M4 branch of the MCA. Preoperative DSA revealed moderate (n = 1) or severe (n = 3) stenosis or occlusion (n = 4) of the ipsilateral ICA and mild (n = 2), moderate (n = 4), or severe (n = 2) stenosis of the contralateral ICA. The baseline Suzuki stage was 4 (n = 7) or 5 (n = 1). The collateral supply originated exclusively from the intracranial circulation in 4/8 patients (50%), and from both the intracranial and extracranial circulation in the remaining 50% of patients. Seven (88%) of 8 patients improved symptomatically during the acute postoperative period with induced hypertension. The modified Rankin Scale (mRS) score at discharge was worse than baseline in 7/8 patients (88%), whereas 1 patient had only minor deficits that did not affect the mRS score. At the 3-year follow-up, 3/8 patients (38%) were at their baseline mRS score or better, 1 patient had significant disability compared with preoperatively, 2 patients had died, and 1 patient was lost to follow-up. Three-year follow-up is not yet available in 1 patient.

CONCLUSIONS

Acute occlusion of the ICA on the contralateral side from an STA-MCA bypass is a rare, but potentially serious, complication of revascularization surgery for MMD. It highlights the importance of the hemodynamic interrelationships that exist between the two hemispheres, a concept that has been previously underappreciated. Induced hypertension during the acute period may provide adequate cerebral blood flow via developing collateral vessels, and good outcomes may be achieved with aggressive supportive management and expedited contralateral revascularization.

Surgery for Moyamoya Disease in Children

Moyamoya disease is a chronic progressive cerebrovascular occlusive disease of the terminal portion of the internal carotid arteries associated with an acquired abnormal vascular network at the base of the brain, often leading to ischemic or hemorrhagic stroke. Moyamoya disease is a relatively common cause of pediatric stroke with a specific racial and well-identified clinical and imaging phenotype. Moyamoya disease is more prevalent in East Asian countries compared with other geographic regions with a higher incidence of familial cases and clinically more aggressive form. Moyamoya disease is one of the few causes of stroke that is amenable to effective surgical revascularization treatment. There are various surgical options available for revascularization, including the direct, indirect, or combined bypass techniques, each with variable responses. However, due to the heterogeneity of the diseases, different clinical course, geographical variables associated with the disease, and availability of a wide variety of surgical revascularization procedures, optimal selection of a surgical candidate and the surgical technique becomes challenging, particularly in the pediatric population. This brief review presents pertinent literature of clinical options for the diagnosis and surgical treatment of moyamoya disease in children.

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.

Time Course of Neoangiogenesis After Indirect Bypass Surgery for Moyamoya Disease : Comparison of Short-term and Long-term Follow-up Angiography

OBJECTIVE

Indirect bypass surgery, which induces spontaneous neoangiogenesis in ischemic brain tissue and improves cerebral blood flow, is an effective treatment for moyamoya disease (MMD). The time course of neoangiogenesis development has not yet been investigated. This study aimed to determine the critical period of neovascularization after indirect bypass in MMD patients.

METHODS

Patients with MMD who underwent indirect bypass surgery at Peking University International Hospital between January 2015 and October 2017 were retrospectively reviewed. Surgically treated hemispheres with short-term (3-6 months) and long-term (1 year) follow-up digital subtraction angiography (DSA) were included. The effects of revascularization were evaluated on lateral and anteroposterior views using angiography and compared between two follow-ups of the same hemisphere.

RESULTS

This study included 25 hemispheres from 24 MMD patients (mean age: 22.48 ± 14.83 years), among whom 13 were pediatric patients and 12 were adults. Qualitative measurements including the Matsushima scale and coverage of neoangiogenesis on anteroposterior views were not significantly different between the short term and long term (P = 0.083 and P = 0.157, respectively). Quantitative measurements including the greatest width and height of the area covered by neovascularization on lateral views of DSA and the greatest depth of neovascularization penetration on anteroposterior views (P = 0.488, 0.298 and 0.527, respectively) were also not significantly different. The mean count of newly formed veins was more at long-term than short-term follow-up (5.5 ± 2.5 vs. 5.1 ± 2.4, P = 0.005). Subgroup analysis of pediatric patients and adults yielded the same results as in the whole series.

CONCLUSION

After indirect bypass surgery, the major time window of arterial neoangiogenesis development was within 6 months after surgery. The general effect of revascularization was very similar in the short and long term; therefore, a follow-up angiography scheduled at 6 months after surgery is recommended. Growth of veins might continue after 6 months.

Neuropsychological impacts of indirect revascularization for pediatric moyamoya disease

PURPOSE

Moyamoya disease (MMD) commonly leads to neurocognitive impairment. This study was carried out to show that temporal encephaloduroarteriosynangiosis (EDAS) has a positive neuropsychological impact on pediatric MMD patients.

METHODS

Fifty-five participants diagnosed with MMD from 2008 to 2014 were included in this retrospective study. The mean age at the preoperative evaluation was 9.5 years and the mean age at postoperative evaluation was 10.4. The average interval of initial and follow-up test was 10 months. K-WISC-III, Rey-Kim memory test, Children's Color Trails test (CCTT), Wisconsin Card Sorting Test (WCST), and Advanced Test of Attention (ATA) were used to evaluate patient's neurocognitive profile.

RESULTS

In this study, preoperative and postoperative neuropsychological fields were compared. Prior operation, pediatric MMD patients showed 54.2% deficit of inattention but only around 2.5% deficit in verbal memory recall function. There was a significant increase of performance IQ and PO score component of PIQ improved almost 10 scores after surgery. For memorial function, there was an improvement of approximately 10 scores in MQ after the surgery. This study also showed parietal activation following surgical treatment which enhanced the ability to interpret visual materials, to register and to retrieve visual information. Interestingly, despite the parietal cover surgery, there was a significant improvement of performance on WCST and CCTT measuring the prefrontal executive function. Concerning failure to maintain set, no significant postoperative improvements were made. However, simple and selective visual attention on ATA was significantly improved postoperatively.

CONCLUSIONS

The results from neuropsychological field comparison testifies the effectiveness of temporal EDAS in pediatric MMD patients. The surgery not only enhances the blood flow in operative regions, but it also improves the broad cerebral function including frontoparietal domains. Such alteration leads to overall advancement in cognitive function which are impaired due to MMD.

Late Cerebrovascular Events and Social Outcome after Adolescence: Long-term Outcome of Pediatric Moyamoya Disease

In this article, the authors review the literature related to long-term outcome of pediatric moyamoya disease, focusing on late cerebrovascular events and social outcome of pediatric patients once they reach adulthood. Late-onset de novo hemorrhage is rare but more serious than recurrence of ischemic stroke. Long-term follow-up data on Asian populations suggest that the incidence of de novo hemorrhage might increase at age 20 or later, even more than 10 years after bypass surgery. Social adaptation difficulty, possibly related to cognitive impairment caused by frontal ischemia, continues in 10-20% of patients after they reach adulthood, even if no significant disability is present in daily life. A treatment strategy aimed at improving long-term outcome and careful follow-up might be required.

Long-term Outcomes After Encephaloduroarteriosynangiosis in Adult Patients with Moyamoya Disease Presenting with Ischemia

BACKGROUND

In adult Moyamoya disease (MMD), there remains controversy about the effectiveness of revascularization surgeries because randomized studies have not been performed to compare the efficacy of surgical techniques. This study was conducted to assess the most appropriate surgical treatment for adult patients with MMD.

METHODS

Encephaloduroarteriosynangiosis (EDAS) was performed on 247 hemispheres in 145 patients. The clinical and demographic characteristics of patients were obtained via retrospective chart review. Clinical and angiographic states were evaluated retrospectively using quantitative methods. The mean duration of clinical follow up was 141.4 ± 19.5 months.

RESULTS

A total of 247 EDAS procedures were performed in 145 patients, including 15 EDAS performed using the occipital artery as the donor vessel. The mortality rate was 0%, and the permanent morbidity rates were 1.2% per operation and 2.0% per person. The mean modified Rankin Scale score was 1.21 ± 1.31 postoperatively and 1.01 ± 1.39 at the last follow-up. Of the 109 hemispheres studied, 45% were classified as grade A, 34% as grade B, and 21% as grade C collateral circulation. The annual rates of stroke were calculated to be 0.73% per person-year. Overall, the 1-,5-, and 10-year actuarial stroke rates were 2.1±1.2%, 6.8±2.1%, and 8.9±2.4%, respectively. Bilateral involvement was a common significant factor in any, hemorrhagic, and ischemic strokes. Hypertension was a risk factor for ischemic strokes during follow-up.

CONCLUSIONS

EDAS is an effective procedure in a Chinese cohort of patients with MMD. EDAS resulted in satisfactory long-term improvement of clinical states and prevention of recurrent strokes.

Adolescents with moyamoya disease: clinical features, surgical treatment and long-term outcomes

BACKGROUND

This study aimed to elucidate the clinical features, surgical treatment and long-term outcomes of adolescent patients with moyamoya disease.

METHODS

We reviewed consecutive patients with moyamoya vasculopathy who were admitted to our hospital from 2009 to 2015 to identify adolescent patients with moyamoya disease. Clinical features, surgical treatment and long-term outcomes were analyzed. Follow-up was performed by face-to-face or structured telephone interviews. Outcome measures were future stroke events. We performed univariate and multivariate time-to-event analyses to identify risk factors associated with future stroke events.

RESULTS

A total of 95 adolescent patients with moyamoya disease (age at onset, 13.1 ± 2.3 years) were included in this study. During follow-up, 12 patients (12.6%) had stroke events. We found that the patients who underwent direct/combined bypass had a significantly lower risk of future strokes [hazard ratio (HR), 0.16; 95% confidence interval (CI), 0.03-0.74; P = 0.019] compared to patients who underwent indirect bypass.

CONCLUSIONS

Our results demonstrate that direct/combined bypass can be more effective in preventing future strokes than indirect bypass in adolescent patients with moyamoya disease.

Moore J, Adeeb N, Griessenauer CJ, Patel AS, Chua MH, Thomas AJ, Ogilvy CS. Clinical presentation, progression, and treatment outcomes of moyamoya disease in the elderly

BACKGROUND

Moyamoya disease is a vascular disorder characterized by progressive stenosis of the internal carotid artery. The presentation, progression, treatment options, and post-operative clinical outcomes for elderly (60 and older) Moyamoya patients have never been reported.

METHODS

A retrospective analysis of all patients who were diagnosed with Moyamoya disease by the senior authors between 1991 and 2016 was performed. Patients who were 60 years or older at the time of surgery or last follow-up were further evaluated.

RESULTS

Seventy patients were diagnosed with probable or definite Moyamoya disease during the study period (1991-2016). Eight patients (11.4 %; six females: two males; median age 63; range, 60-71 years) were found to be 60 years or older at the time of surgery or last follow-up and were included in the study. All patients had a modified Rankin scale (mRS) of either one or two (median 1) pre-operatively. Six patients (75 %) underwent surgical treatment on a total on seven hemispheres. Post-surgery, one patient had an improved mRS score, three had no changes, and two had worsening in their mRS scores. Both patients who did not undergo surgical interventions suffered from intra-parenchymal hemorrhages post-diagnosis.

CONCLUSIONS

Moyamoya disease is most commonly seen in young and middle-aged patients. Presentation in the elderly (defined as 60 years and older in this study) is rare, and has never been reported in the literature. In this study, both direct and indirect revascularization procedures demonstrated potential benefit in some of these patients, with stabilization of progressive symptoms.

Cognitive Outcome of Pediatric Moyamoya Disease

Quality of life is the current trend and issue for the most of human diseases. In moyamoya disease (MMD), surgical revascularization has been recognized as the possible assistance to reduce the neurological insult. However, the progressive nature of the disease has been invincible so far. To improve the quality of life of MMD patients not only the protection from the neurological insult but also the maintenance or improvement of cognitive function is inevitable. For pediatric MMD patients, younger age or longer duration of disease is the key factor among the prognostic factors for bad neurological outcomes. Hence, 'the earlier, the better' is the most precious rule for treatment. Protection from neurological insult is very critical and foremost important to improve cognitive outcome. Clinicians need to know the neuropsychological profile of MMD patients for the care of whole person and make an effort to protect the patients from neurological insults to maintain or improve it.

Surgical Revascularization in North American Adults with Moyamoya Phenomenon: Long-Term Angiographic Follow-up

BACKGROUND

North American and Asian forms of moyamoya have distinct clinical characteristics. Asian adults with moyamoya are known to respond better to direct versus indirect revascularization. It is unclear whether North American adults with moyamoya have a similar long-term angiographic response to direct versus indirect bypass.

METHODS

A retrospective review of surgical revascularization for adult moyamoya phenomenon was performed. Preoperative and postoperative cerebral angiograms underwent consensus review, with degree of revascularization quantified as extent of new middle cerebral artery (MCA) territory filling.

RESULTS

Late angiographic follow-up was available in 15 symptomatic patients who underwent 20 surgical revascularization procedures. In 10 hemispheres treated solely with indirect arterial bypass, 3 had 2/3 revascularization, 4 had 1/3 revascularization, and 3 had no revascularization of the MCA territory. In the 10 hemispheres treated with direct arterial bypass (8 as a stand-alone procedure and 2 in combination with an indirect procedure), 2 had complete revascularization, 7 had 2/3 revascularization, and 1 had 1/3 revascularization. Direct bypass provided a higher rate of "good" angiographic outcome (complete or 2/3 revascularization) when compared with indirect techniques (P = .0198).

CONCLUSIONS

Direct bypass provides a statistically significant, more consistent, and complete cerebral revascularization than indirect techniques in this patient population. This is similar to that reported in the Asian literature, which suggests that the manner of presentation (ischemia in North American adults versus hemorrhage in Asian adults) is likely not a contributor to the extent of revascularization achieved after surgical intervention.

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

PURPOSE

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Long-Term Outcomes After Combined Revascularization Surgery in Adult Moyamoya Disease

Background and Purpose—

The surgical outcomes of adult moyamoya disease are rarely reported. We aimed to evaluate the long-term outcomes of combined revascularization surgery in patients with adult moyamoya disease.

Methods—

Combined revascularization surgery consisting of superficial temporal artery–middle cerebral artery anastomosis with encephalodurogaleosynangiosis was performed on 77 hemispheres in 60 patients. Clinical, angiographic, and hemodynamic states were evaluated retrospectively using quantitative methods preoperatively and postoperatively in the short-term (≈6 months) and long-term (≈5 years) periods. The mean clinical follow-up duration was 71.0±10.1 months (range, 60–104 months).

Results—

Clinical status improved until 6 months after surgery and remained stable thereafter, as assessed by the Karnofsky Performance Scale and modified Rankin Scale. The revascularization area relative to supratentorial area significantly increased in the long-term period compared with that in the short-term period (54.8% versus 44.2%; P <0.001). Cerebral blood flow in the territory of the middle cerebral artery improved in the short-term period compared with that in the preoperative period (68.7 versus 59.1; considering blood flow of the pons as 50; P <0.001) and thereafter became stable (65.5 in the long term; P =0.219). The annual risks of symptomatic hemorrhage and infarction were 0.4% and 0.2%, respectively, in the operated hemispheres.

Conclusions—

Combined revascularization surgery resulted in satisfactory long-term improvement in clinical, angiographic, and hemodynamic states and prevention of recurrent stroke.

Long-term outcomes in adult patients with ischemic-type moyamoya disease involving posterior circulation

BACKGROUND

The object of this study was to compare the long-term outcomes in adult patients with moyamoya disease (MMD) with posterior circulation involvement (PCi) treated through surgical revascularization with those in adult patients without PCi.

METHODS

The records of 32 consecutive adult patients with ischemic-type MMD who were treated with revascularization were reviewed. Twelve of these patients (38 %) had PCi at initial onset. Clinical characteristics of the patients with PCi were compared to those without PCi. Neurological outcomes were assessed using the modified Rankin Scale (mRS) in the preoperative and postoperative follow-up periods. A five-year Kaplan-Meier stroke risk was calculated.

RESULTS

The frequency of presenting with infarction was significantly higher among patients with PCi than among those without PCi (p = 0.006). mRS scores in the preoperative period were significantly higher in patients with PCi than in patients without PCi (p = 0.0004). There were no significant differences in mRS scores between the preoperative and postoperative follow-up period in patients with PCi (p = 0.3), nor were there any between the preoperative and postoperative follow-up periods in patients without PCi (p = 0.2). The five-year Kaplan-Meier risk of surgical morbidity and ipsilateral stroke was 14.3 % in surgically treated hemispheres with PCi versus 14.9 % in surgically treated hemispheres without PCi (p = 0.96).

CONCLUSIONS

PCi at initial onset was significantly correlated with poor outcome. Revascularization for the middle cerebral artery territory in patients with PCi was effective at preventing recurrent ischemic stroke.

Impact of posterior cerebral artery involvement on long-term clinical and social outcome of pediatric moyamoya disease

OBJECT

In the study of pediatric moyamoya disease, information on long-term social outcomes and risk factors for unfavorable social outcomes remains insufficient. The authors analyzed the long-term results of surgical revascularization for pediatric patients with moyamoya disease to determine whether the involvement of a stenoocclusive lesion in the posterior cerebral artery (PCA), relatively common in pediatric moyamoya disease, represents an underlying predictor for unfavorable social outcomes.

METHODS

Prospectively collected data on 61 consecutive patients with moyamoya disease who had undergone combined bypass surgery were analyzed. Neuroradiological features and other baseline clinical factors were incorporated into univariate and multivariate analyses to determine any association with an unfavorable social outcome, defined as difficulty attending regular school or obtaining regular employment.

RESULTS

Posterior cerebral artery involvement detected by angiography on admission was noted in 22 (36.1%) of the 61 patients. Follow-up data were acquired in 56 patients (91.8%), and the mean follow-up period was 15.8 years. While transient ischemic attacks were eliminated in 52 (92.9%) of these 56 patients after surgery, and late-onset ischemic stroke was observed in only 1 patient during the follow-up period, 10 (17.9%) experienced an unfavorable social outcome. Although younger age at onset, longer duration between onset and surgery, infarction present on preoperative neuroradiological images, and PCA involvement had been identified as risk factors for an unfavorable social outcome in univariate analysis, only infarction present on preoperative images and PCA involvement remained statistically significant after multivariate adjustment.

CONCLUSIONS

Posterior cerebral artery involvement can be considered one of the underlying risk factors for unfavorable social outcome and should be studied further to improve social outcome in pediatric moyamoya disease.

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.

Novel Bypass Surgery for Moyamoya Disease Using Pericranial Flap: Its Impacts on Cerebral Hemodynamics and Long-term Outcome

OBJECTIVE

We reviewed our 11-year experience with a novel bypass procedure, superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis and encephalo-duro-myo-arterio-pericranio-synangiosis (EDMAPS), for moyamoya disease regarding cerebral hemodynamics and long-term outcome.

METHODS

This prospective study included 75 patients with moyamoya disease, including 28 children and 47 adults. We performed STA-MCA anastomosis and EDMAPS on 123 hemispheres of 75 patients. In addition to conventional STA-MCA anastomosis and indirect bypass for the MCA territory, the medial frontal lobe was revascularized using the frontal pericranial flap through medial frontal craniotomy. Surgical results were analyzed with magnetic resonance imaging, cerebral angiography, and single-photon emission computed tomography/positron emission tomography.

RESULTS

Overall incidences of mortality and morbidity were 0% and 5.7%, respectively. The annual risk of cerebrovascular events during the follow-up periods was very low: 0% in pediatric patients and 0.4% in adults over approximately 67 months. Postoperative cerebral angiography showed that the pericranial flap functioned well as donor tissue for indirect bypass, especially in pediatric patients. Follow-up single-photon emission computed tomography/positron emission tomography studies revealed that cerebral blood flow and its reactivity to acetazolamide markedly improved in both the MCA and anterior cerebral artery territories.

CONCLUSION

These findings strongly suggest that STA-MCA anastomosis and EDMAPS using a frontal pericranial flap is a safe and effective surgical procedure to further improve the long-term prognosis in moyamoya disease by improving cerebral hemodynamics in both the MCA and anterior cerebral artery territories.

Clinical features, surgical treatment, and long-term outcome in adult patients with moyamoya disease. Clinical article

OBJECT

The object of this study was to report the clinical features, surgical treatment, and long-term outcomes in adults with moyamoya phenomenon treated at a single institution in the US.

METHODS

Forty-three adult patients with moyamoya disease (mean age 40 +/- 11 years [SD], range 18-69 years) were treated with encephaloduroarteriosynangiosis (EDAS). Neurologists examined patients pre- and postoperatively. Follow-up was obtained in person or by structured telephone interview (median 41 months, range 4-126 months). The following outcomes were collected: transient ischemic attack (TIA), infarction, graft collateralization, change in cerebral perfusion, and functional level according to the modified Rankin scale (mRS). Kaplan-Meier estimates of infarction risk were calculated for comparison of surgically treated and contralateral hemispheres.

RESULTS

The majority of patients were women (65%), were Caucasian (65%), presented with ischemic symptoms (98%), and had bilateral disease (86%). Nineteen patients underwent unilateral and 24 patients bilateral EDAS (67 treated hemispheres). Collateral vessels developed in 50 (98%) of 52 hemispheres for which imaging was available and there was evidence of increased perfusion on SPECT scans in 41 (82%) of the 50 hemispheres evaluated. Periprocedural infarction (< 48 hours) occurred in 3% of the hemispheres treated. In the follow-up period patients experienced 10 TIAs, 6 infarctions, and 1 intracranial hemorrhage. Although the hemisphere selected for surgery was based upon patients' symptoms and severity of pathology, the 5-year infarction-free survival rate was 94% in the surgically treated hemispheres versus < 36% in the untreated hemispheres (p = 0.007). After controlling for age and sex, infarction was 89% less likely to occur in the surgically treated hemispheres than in the contralateral hemispheres (hazard ratio 0.11, 95% CI 0.02-0.56). Thirty-eight (88%) of 43 patients had preserved or improved mRS scores, relative to baseline status.

CONCLUSIONS

In this mixed-race population of North American patients, indirect bypass promoted adequate pial collateral development and increased perfusion in the majority of adult patients with moyamoya disease. Patients had low rates of postoperative TIAs, infarction, and hemorrhage, and the majority of patients had preserved or improved functional status.

Optimal surgical treatment for moyamoya disease in adults: direct versus indirect bypass

Moyamoya disease is a chronic cerebrovascular occlusive disorder that results in severe morbidity and death. There is much controversy surrounding the optimal treatment for adult patients with the disorder. There have been no randomized trials to assess the efficacy of any single surgical treatment, and existing case series suffer from inadequate power, selection bias, and inherent differences in patient characteristics. In this article the authors review the literature concerning the optimal surgical treatment of adult patients with moyamoya disease.

Long-term outcome of superficial temporal artery-middle cerebral artery bypass for patients with moyamoya disease in the US

OBJECT

The authors report the long-term results of a series of direct superficial temporal artery-middle cerebral artery (STA-MCA) bypass procedures in patients with moyamoya disease from the western US.

METHODS

All patients with moyamoya disease treated at the University of Washington from 1990 through 2004 (39 patients) were included in this study. Patients underwent pre- and postoperative evaluation of cerebral perfusion dynamics. Surgical revascularization procedures were performed in all patients with impaired cerebral blood flow (CBF) findings.

RESULTS

The mean age of patients at diagnosis was 34 years (range 10-55 years). All 39 patients had impaired CBF and/or vasomotor reserve and underwent revascularization procedures: 26 patients underwent bilateral operations, 13 unilateral (65 total procedures). An STA-MCA bypass was technically possible in 56 procedures (86.2%); saphenous vein interposition grafts were required in 3 procedures (4.6%); encephaloduroarteriosynangiosis was performed in 6 procedures (9.2%). Three patients died due to postoperative complications, yielding a procedure-related mortality rate of 4.61%, and 8 experienced non-life threatening complications (for a procedure-related rate of 12.3%). Long-term follow-up appeared to indicate a reduction in further ischemic events in surviving patients compared with the natural history. Cerebral perfusion dynamics improved postoperatively in all 36 surviving patients.

CONCLUSIONS

Moyamoya disease may differ in the US and Asia, and STA-MCA bypass procedures may prevent future ischemic events in patients with this condition.

Aortocarotid bypass for hemispheric hypoperfusion in a child

Large-vessel vasculitis syndromes in the pediatric population are rare and highly morbid. The authors here report on the microsurgical revascularization of a unique case of presumed vasculitis with aortitis and severe obliterative arteriopathy in a 10-month-old child with symptomatic hemispheric hypoperfusion. Using a cryopreserved saphenous vein, this unilateral aortocarotid bypass restored normal intracranial perfusion bilaterally and led to a resolution of the patient's ischemic symptoms. The aortocarotid bypass is clinically effective and technically feasible in young children when a saphenous vein allograft is used. The bypass graft is amenable to angioplasty with or without stenting if delayed stenosis becomes an issue later in life.

Primary Percutaneous Transluminal Angioplasty for Early Moyamoya Disease

Moyamoya disease is a progressive steno-oclusive arteriopathy of the circle of Willis that manifests on cerebral angiography with a characteristic net of vessels at the base of the brain representing collateralization. Described initially in Japan where children present with cerebral ischemia and adults with hemorrhagic stroke, it was recognized to have a more benign course in the United States, mainly causing cerebral ischemic events in young adults. Medical treatment is not intended to stop the progression of the disease and surgery is not exempt of risks. We present a patient with early moyamoya disease in the United States in whom primary transluminal angioplasty, a less invasive procedure, was performed to treat the stenotic arteriopathy with good immediate and sustained clinical and angiographic results, without evidence of restenosis at the site of angioplasty 2 years later.

Postoperative electroencephalogram for follow up of pediatric Moyamoya disease

It is well known that the electroencephalographic finding in patients with moyamoya disease demonstrates the characteristic "re-build up" phenomenon a few minutes after hyperventilation. To evaluate the usefulness of an electroencephalogram (EEG) in the postoperative management of children with moyamoya disease, we studied the presence or absence of improvement in the clinical, single photon emission computed tomography (SPECT) and EEG findings, before and after surgery. Twenty-two patients, who underwent indirect revascularization surgery for moyamoya disease, were included in our study. Clinical improvement was assessed as the disappearance or decrease of a transient ischemic attack or headache. The findings on the EEG and SPECT were considered improved when the re-build up phenomenon was absent and when there was improvement in the cerebrovascular reserve as a result of the acetazolamide challenge test. The statistical correlation analysis for both clinical and EEG improvement were consistent (kappa value=0.409, p< 0.05). However, the result from the clinical and SPECT improvement as well as that from EEG and SPECT improvement were not statistically significant. Our results suggest that EEG can be used as a noninvasive and simple follow-up test for moyamoya disease after indirect revascularization surgery if the hyperventilation procedure is effectively performed during EEG recording.

Unilateral (probable) moyamoya disease: long-term follow-up of seven cases

OBJECTS

Some cases of unilateral involvement have angiographic findings on the affected side which resemble those of definite cases of moyamoya disease (MMD). We analyzed these cases to determine whether the entity "unilateral MMD" actually exists and whether unilateral involvement represents only the early phase of the pathologic process found in definitive bilateral disease.

METHODS

Between 1988 and 2000, seven cases of unilateral MMD were evaluated. The male-to-female ratio was 2:5, mean age was 5.1 years (7 months to 8 years), and mean follow-up duration was 64.7 months. The presenting symptoms of these cases were similar to those of definite MMD, and no familial occurrence was found. Two of the seven unilateral MMD cases showed progression to bilateral involvement. However, the remaining cases showed no evidence of contralateral progression during the follow-up period.

CONCLUSIONS

Most cases of unilateral MMD seem to be an unusual form of stenoocclusive process of the proximal intracranial arteries, distinguishing the condition from definite MMD. Surgical treatment on the symptomatic side and close observation for signs of bilateral involvement are necessary.

Middle cerebral artery stenosis: endovascular and surgical options

Atherosclerotic middle cerebral artery stenosis is a rare but potentially devastating cause of cerebral ischemia and stroke. While medical management remains the mainstay for stroke prevention, surgical and/or endovascular intervention is indicated in selected patients. This article reviews the role of surgery and endovascular techniques in the treatment of middle cerebral artery stenosis based on its natural history, pathophysiology, and prognosis when treated medically.

Prediction of the clinical outcome of pediatric moyamoya disease with postoperative basal/acetazolamide stress brain perfusion SPECT after revascularization surgery

BACKGROUND AND PURPOSE

We evaluated whether basal/acetazolamide stress brain perfusion SPECT performed after revascularization surgery can predict the further clinical outcome of patients with pediatric moyamoya disease.

METHODS

A total of 77 (31 males, 46 females, age 6.6+/-3.2 years) patients with postoperative pediatric moyamoya disease who underwent basal/acetazolamide stress brain perfusion SPECT 6 to 12 months after revascularization surgery and who were followed-up >12 months after SPECT were included. Mean follow-up period after SPECT was 36+/-19 months. Sixty-two patients underwent bilateral ribbon encephaloduroarteriosynangiosis (EDAS), 14 bilateral EDAS, and 1 unilateral EDAS. Ordinal logistic regression analysis using 5 independent variables (infarction on preoperative MRI, age at the first operation, highest Suzuki stage on cerebral angiography, and regional cerebrovascular reserve on postoperative SPECT) against postoperative clinical outcomes was performed.

RESULTS

Fifty-one patients had preserved reserve on postoperative SPECT and their clinical outcomes were excellent (30), good (15), fair (4), and poor (2); 26 patients had decreased reserve (excellent, 1; good, 7; fair, 14; poor, 4). On ordinal logistic regression analysis, age at the first operation (P=0.033) and reserve on postoperative SPECT (P<0.001) were statistically significant.

CONCLUSIONS

Basal/acetazolamide stress brain perfusion SPECT performed at 6 to 12 months after the indirect bypass operation could predict the further clinical outcome of pediatric patients with moyamoya disease. Patients with decreased cerebrovascular reserve will have remaining neurological deficit and ischemic attacks on follow-up.

Revascularisation surgery for paediatric moyamoya: a review of the literature

INTRODUCTION AND AIMS

The role of and optimal surgical revascularisation technique for paediatric moyamoya syndrome (MMS) are controversial. In this literature review our primary aim was to evaluate the evidence base for the efficacy of surgical revascularisation for the treatment of paediatric MMS. Secondary aims were to estimate the rate of peri-operative complications and to ascertain whether direct or indirect revascularisation techniques resulted in differences in clinical or radiological outcomes.

METHODS

Papers describing surgical revascularisation and its outcome in the treatment of children with MMS were identified from the OVID Medline database (1966-2004). Only papers in English were reviewed. Data were abstracted using a standardised form.

RESULTS

Fifty-seven studies, including data on 1,448 patients, were reviewed. Most were Japanese; 10% were from Western institutions. Indications for revascularisation were described in <15% of studies and varied between centres. Indirect procedures were most commonly performed (alone in 73% of cases, combined with direct procedures in 23%). The rates of peri-operative stroke and reversible ischaemic events were 4.4 and 6.1% respectively. Out of 1,156 (87%) patients, 1,003 derived symptomatic benefit from surgical revascularisation (complete disappearance or reduction in symptomatic cerebral ischaemia), with no significant difference between the indirect and direct/combined groups. Data on developmental and functional outcomes were limited and of uncertain significance as they were not related to pre-operative status. Good collateral formation was significantly more frequent in the direct/combined group than in the indirect group (chi(2), p<0.001).

CONCLUSIONS

Data from the medical literature suggest that surgical revascularisation is a safe intervention for paediatric MMS and most treated patients derive some symptomatic benefit. However, paucity of data on selection criteria and more global outcome measures means that the impact of surgical revascularisation on natural history remains uncertain. Direct and/or combined procedures provide better revascularisation, but this is not associated with differences in symptomatic outcome. International standardisation of the clinical approach to the treatment of paediatric MMS is urgently needed to critically evaluate the optimal indications for and timing of surgical revascularisation.

Sickle cell anemia with moyamoya disease: outcomes after EDAS procedure

Moyamoya disease is a relatively uncommon neurovascular complication of sickle cell anemia. We report a case series of six patients with sickle cell anemia who developed moyamoya disease and underwent encephaloduroarteriosynangiosis procedures. These six patients presented with either cerebrovascular accidents, transient ischemic attacks, or seizures, and subsequent magnetic resonance imaging scans were suggestive of moyamoya-like changes in the cerebral vasculature. Conventional cerebral angiography was used to confirm the diagnosis in all six patients. Four of six patients manifested a cerebrovascular accident before surgery, and two of these patients were compliant on a transfusion protocol at the time of their cerebrovascular accident. Bilateral (n = 4) or unilateral (n = 2) encephaloduroarteriosynangiosis procedures were performed without any complications. The patient who was stroke-free preoperatively had a cerebrovascular accident 2 weeks after the procedure; otherwise, all patients have remained free of neurovascular complications with an average follow-up of 33 months. Collateral anastomoses between external and internal carotid arteries were established by magnetic resonance angiography in three patients. The encephaloduroarteriosynangiosis procedure is a safe and effective treatment option in patients with sickle cell anemia who develop moyamoya disease.

Ischemic stroke therapy

Stroke is the most common life-threatening neurologic disease and the leading cause of serious long-term disability. The advent of new treatment options for selected patients suffering ischemic stroke (such as systemic administration of tissue plasminogen activator or catheter-guided intra-arterial thrombolysis), the structural reorganization of patient care facilities into stroke units, and interdisciplinary cerebrovascular centers have broadened the scope of possible therapeutic interventions in the acute and post-acute phase after cerebral ischemia. This review summarizes currently available and recommended treatment modalities for acute ischemic stroke from an interdisciplinary perspective, including medical, neurointerventional, and neurosurgical therapies.

Surgical approaches to vascular anomalies of the child's brain

The population of pediatric patients with cerebrovascular disease presents a unique set of challenges to the neurosurgeon. The wide scope of pathology, including arteriovenous malformations, cavernous malformations and moyamoya disease, coupled with marked advances in diagnosis and treatment of these conditions over the past several years has resulted in a proliferation of the literature related to this subject. The present review provides an overview of current methods of surgical treatment for pediatric cerebrovascular diseases, focusing on indications and use of recent refinements of pre-existing surgical approaches, and newly evolved operative techniques developed to treat these entities.

Combined encephaloduroarteriosynangiosis and bifrontal encephalogaleo(periosteal)synangiosis in pediatric moyamoya disease

OBJECTIVE

We compared the surgical results of simple encephaloduroarteriosynangiosis (EDAS) and EDAS with bifrontal encephalogaleo(periosteal)synangiosis for the treatment of pediatric moyamoya disease.

METHODS

Data for 159 children (up to 15 yr of age, 76 boys and 83 girls) who underwent indirect revascularization procedures for the treatment of moyamoya disease between 1987 and 1998 were retrospectively reviewed. Group A patients underwent simple EDAS (n = 67). Group B patients underwent EDAS with bifrontal encephalogaleo(periosteal)synangiosis (n = 92). The surgical results for each group were compared, in terms of clinical outcomes, neuroimaging changes, extent of revascularization evident on angiograms, and hemodynamic changes evident on single-photon emission computed tomographic scans. The average follow-up periods were 45 months for Group A and 22 months for Group B.

RESULTS

The overall clinical outcomes and neuroimaging changes tended to be better for Group B. In terms of single-photon emission computed tomographic changes of the whole brain after surgery, Group B patients exhibited more favorable outcomes than did Group A patients (62 versus 36%, P = 0.003). The surgical results for the anterior cerebral artery territory were significantly better for Group B than for Group A, with respect to outcomes of anterior cerebral artery symptoms (81 versus 40%, P = 0.015), revascularization on angiograms (79 versus 16%, P < 0.001), and hemodynamic changes on single-photon emission computed tomographic scans (70 versus 52%, P = 0.002). The incidences of postoperative infarctions were not significantly different between the two groups.

CONCLUSION

EDAS with bifrontal encephalogaleo(periosteal)synangiosis is a more effective surgical modality for the treatment of pediatric moyamoya disease, compared with simple EDAS, because it covers both the middle cerebral artery and anterior cerebral artery territories of the brain.

Central deafness in a young child with Moyamoya disease: paternal linkage in a Caucasian family: two case reports and a review of the literature

A case of 'central deafness' is presented in a 3-year-old male Caucasian child with Moyamoya disease (MMD); a rare, progressive and occlusive cerebrovascular disorder predominantly affecting the carotid artery system. Documentation of normal peripheral auditory function and brainstem pathway integrity is provided by acoustic admittance, otoacoustic emission and brainstem auditory evoked potential measurements. The lack of behavioral response to sound, and absent middle and long latency auditory evoked potentials suggest thalamo-cortical dysfunction. Magnetic resonance imaging showed diffuse ischemic damage in subcortical white matter including areas of the temporal lobes. In addition, there were multiple and focal cortical infarctions in both cerebral hemispheres, focused primarily in the frontal, parietal and temporal areas. Taken together, these structural and functional abnormalities in addition to severely delayed speech and language development are consistent with the diagnosis of central deafness and suggest a disconnection between higher brainstem and cortical auditory areas. The child's father also has MMD, but was diagnosed only recently. The presence of paternal linkage is informative since it rules out x-linked recessive and maternal inheritance. To our knowledge, this represents the first documented case of paternal linkage in MMD with central deafness in a Caucasian child with no apparent Japanese ancestry. Herein, we focus on central auditory dysfunction and consider how lesion-induced changes have contributed to a deficit in basic auditory responsiveness, including a severe disturbance in receptive and expressive auditory-based speech and language skills.