Pediatric moyamoya disease: An analysis of 410 consecutive cases

Paediatric moyamoya in mainland France: a comprehensive survey of academic neuropaediatric centres

BACKGROUND

Epidemiological data of paediatric moyamoya disease/syndrome (MMD/MMS) in non-Asian populations are scarce.

METHODS

A questionnaire was sent to every French neuropaediatric academic centre to estimate the prevalence, incidence, familial form rate and location of paediatric MMD/MMS cases. Specific paediatric data were also retrieved from the most recent nationwide Japanese study.

RESULTS

A 100% response rate was obtained. The prevalence of paediatric MMD/MMS was estimated at 0.39/100,000 children (95% CI: 0.28-0.49), and the incidence was estimated at 0.065/100,000 children/year (95% CI: 0.025-0.12), with 7.5% familial cases. The prevalence was homogenous within the different administrative areas.

CONCLUSIONS

This comprehensive survey of MMD/MMS in academic neuropaediatric centres suggests that the prevalence of the disease in children in France is approximately 1/20th of that estimated in Asia.

Moyamoya disease in China: its clinical features and outcomes

BACKGROUND AND PURPOSE

Here we describe the clinical features and outcomes of patients with moyamoya disease who were surgically treated at a single institution in China.

METHODS

Our cohort included 802 patients with moyamoya disease. Demographic and clinical characteristics were obtained by retrospective chart review; follow-up information and outcome were obtained through clinical visits, telephone, or letter interview. We used the Kaplan-Meier methods to estimate stroke risk by treatment status.

RESULTS

The median age for the onset of symptoms was 28 (range, 0.5-77) years. Two definite peaks in age distribution were found. The ratio of women to men was 1:1 (398/404). Familial occurrence of moyamoya disease was 5.2%. The initial symptom was ischemia, hemorrhage, or others in 564, 113, and 125 patients, respectively. Twenty-nine of the 802 patients (3.6%) received conservative management. The remaining 773 patients (96.4%) underwent neurosurgical revascularization procedures, and 502 of these were bilateral. The median follow-up after surgery (n=773) or conservative management (n=26) was 26.3 months (range, 6.0-101.9 months). Most subsequent ischemic events appeared in the first 2 years after surgery. The Kaplan-Meier estimated stroke risk was 10.1% in the first 2 years, and the 5-year-Kaplan-Meier risk of stroke was 12.7% after surgery for all patients treated with surgical revascularization.

CONCLUSIONS

This study on the clinical features of moyamoya disease in mainland China indicated bimodal incidence distribution with women-to-men ratios of 1:1 and lower rate of hemorrhages in adults compared with in children. Patients had low rates of postoperative ischemic or hemorrhagic strokes, and the majority of patients had preserved functional status after revascularization.

Long-term social outcome in children with moyamoya disease who have reached adulthood

OBJECT

Although the reported surgical outcome is favorable, there is little information regarding the long-term quality of life in pediatric patients with moyamoya disease (MMD) when they grow to adulthood. The authors conducted a survey to provide details of social adaptation and satisfaction in adults who underwent revascularization surgery for MMD during childhood.

METHODS

One hundred twenty-three patients with MMD who had undergone surgery during childhood and were older than 18 years of age were recruited for this study. The authors mailed self-administered questionnaires regarding each patient's education, employment, marriage, driver's license, physical condition, and satisfaction. Sixty-five patients (53%) responded.

RESULTS

Compared with the general population, the patients showed a similar rate of attaining a higher education. Forty-nine (80%) of 61 patients who were not currently high school students had entered college or university. However, the presence of neurological deficits on preoperative examination was a negative predictor of entrance into a college or university, as well as employment. Some patients had difficulty in planning marriage because of physical handicaps, and the rate of acquiring a driver's license and actual driving were relatively low. Approximately 80% of the responders were satisfied with their treatment outcomes, but more than one-half reported subjectively assessed neurological problems.

CONCLUSIONS

In this study, pediatric patients with MMD showed favorable social adaptation in adulthood. The findings also indicated that early diagnosis and intervention before the establishment of neurological deficits are essential to children with MMD in becoming better socially adapted. Further, more thorough clinical examinations are required during follow-up in patients with MMD.

Natural history and progression factors of unilateral moyamoya disease in pediatric patients

PURPOSE

Thirty-four pediatric age patients with unilateral moyamoya disease (MMD) were reviewed to analyze the natural history and the predictive factors for progression to bilateral MMD.

METHODS

Forty out of 259 MMD patients cared for between January 2000 and June 2008 in the Severance Hospital had unilateral lesion. These patients were followed for a mean of 32.3 months for their symptoms and imaging studies. Thirty-four out of 40 patients were included in this study. Magnetic resonance angiography (MRA) and magnetic resonance perfusion (MR perfusion) images were taken for all patients for initial diagnosis and repeated at 6 months from the initial diagnosis and then at yearly basis. Clinical manifestations, the results of imaging studies, outcome of the indirect revascularization procedure, and the progression of the lesion were reviewed in this study.

RESULTS

Of these 34 patients, contralateral progression was identified in 20 patients (58.8%). Fourteen (70%) out of the 20 patients presented with anterior cerebral artery abnormalities at diagnosis progressed to bilateral disease as well as did 5 (83%) out of 6 patients with middle cerebral artery lesions at the initial examination. Among the 34 patients, six exhibited familial history of MMD and all of them progressed to bilateral disease (100%, p < 0.005).

CONCLUSION

Careful and long-term follow-up would be essential to evaluate the hemodynamic status and progression to bilateral disease in unilateral MMD patients to make prompt decision for a surgical revascularization.

Surgical revascularization reverses cerebral cortical thinning in patients with severe cerebrovascular steno-occlusive disease

BACKGROUND AND PURPOSE

Chronic deficiencies in regional blood flow lead to cerebral cortical thinning without evidence of gross tissue loss at the same time as potentially negatively impacting on neurological and cognitive performance. This is most pronounced in patients with severe occlusive cerebrovascular disease in whom affected brain areas exhibit "steal physiology," a paradoxical reduction of cerebral blood flow in response to a global vasodilatory stimulus intended to increase blood flow. We tested whether surgical brain revascularization that eliminates steal physiology can reverse cortical thinning.

METHODS

We identified 29 patients from our database who had undergone brain revascularization with pre- and postoperative studies of cerebrovascular reactivity using blood oxygen(ation) level-dependent MRI and whose preoperative study exhibited steal physiology without MRI-evident structural abnormalities. Cortical thickness in regions corresponding to steal physiology, and where applicable corresponding areas in the normal hemisphere, were measured using Freesurfer software.

RESULTS

At an average of 11 months after surgery, cortical thickness increased in every successfully revascularized hemisphere (n=30). Mean cortical thickness in the revascularized regions increased by 5.1% (from 2.40 ± 0.03 to 2.53 ± 0.03; P<0.0001).

CONCLUSIONS

Successful regional revascularization and reversal of steal physiology is followed by restoration of cortical thickness.