Introduction: Comparative outcomes following surgical and conservative management of moyamoya disease(MMD) in a non-Asian population are rarely reported. We aim to elucidate the role of revascularization surgery in preventing ipsilateral strokes in a North American cohort with MMD.
Methods: We performed a retrospective review of MMD patients at the Johns Hopkins Medical Institutions from 1990-2014. Patient information was analyzed on a per-hemisphere basis, and compared between surgically treated(group1) and conservatively managed patients(group2). Significant factors were included into a multivariate logistic regression analysis(MVA), with the outcome defined as stroke occurrence during follow-up.
Results: A total of 115 patients with 214 affected hemispheres were included. The average age of all patients was 24.4±17.8 years, with 73.9%(n=85) being female. Race distribution was: White(n=46,40.0%), Black(n=32,27.8%), Asian(n=24,20.9%) and Others(n=13,11.3%). Ninety-five hemispheres presented with ipsilateral strokes(44.6%), and 65 with ipsilateral TIAs(30.5%), Most strokes were ischemic(n=81,85.3%), 13 were hemorrhagic(6.1%) and 1 had both(0.5%). Management strategies were: conservative(n=73,34.3%), direct bypass(n=14,6.6%), indirect bypass(n=114,53.5%), both(n=11,5.2%) and burr-hole(n=1,0.5%). There were more male(p<0.001) and Down’s syndrome patients in group1(p=0.036); whereas there were more patients with neurofibromatosis type 1 in group2(p=0.026). No significant differences in baseline TIA or stroke occurrences were observed between the two management groups. However, more patients in group1 were symptomatic at baseline with speech disturbances(p=0.001) and weakness(p=0.067). During an average follow-up of 6.07 years, occurrence of ipsilateral TIA was similar across the two groups(p=0.987). However, group1 had fewer ipsilateral strokes(p=0.019), headaches(p=0.026), and sensory disturbances(p=0.024). In MVA, revascularization reduced the incidence of stroke by 67%(OR=0.33,CI=[0.11,0.89],p=0.036) compared to conservative management at follow-up, after adjusting for other confounding variables.
Conclusions: In our cohort of mostly non-Asian patients with MMD, despite more severe symptomatic presentation, patients who underwent surgical revascularization derived symptom relief and reduced stroke recurrence by 67%. Taken together, surgical treatment should be considered for symptomatic MMD patients with an acceptable surgical risk profile.
Patient Care: Although Moyamoya has been extensively reported in the literature, most study populations are of Asian origin, and few report a study cohort with a predominantly White and Black population, which is a typical race constitution in the Northeast North America region. In addition, direct comparisons of stroke prevention between surgery and conservative management are under-reported in non-Asian literature. The current study provides evidence of the effectiveness of surgical treatment in Moyamoya patients representative of this population.
Learning Objectives: By the conclusion of this session, participants should be able to:
1) Understand the race distribution of a North American Moyamoya cohort
2) Understand the baseline characteristics of Moyamoya presentation in this population
3) Understand that surgery, with mostly indirect bypasses, is still effective in preventing the occurrence of follow-up strokes.