Progression of Unilateral Moyamoya Disease: A Clinical Series

Abstract

Background: The natural history of unilateral moyamoya disease (MMD) in adult patients is not clearly described in the literature. We present a series of 18 patients with unilateral MMD and analyze the risk factors for progression to bilateral disease. Methods: A retrospective review of 157 MMD patients treated at Stanford University Medical Center from 1991 to 2005 identified 28 patients with unilateral MMD (defined as none, equivocal or mild involvement on the contralateral side). Results: Eigh teen patients (5 males and 13 females) were identified with unilateral MMD and angiographic follow-up of ≧5 months. Mean radiologic follow-up (± standard error of the mean) was 19.3 ± 3.4 months and mean clinical follow-up was 24.5 ± 3.7 months. Five patients had childhood onset MMD and 13 patients had adult onset disease. Angiographic progression from unilateral to bilateral disease was seen in 7 patients (38.9%) at a mean follow-up of 12.7 ± 2.4 months. Four of the 7 patients had significant clinical and radiologic progression requiring surgical intervention. Five of 7 patients that progressed had adult onset MMD. The presence of equivocal or mild stenotic changes of the contralateral anterior cerebral artery (ACA), middle cerebral artery (MCA) or internal carotid artery (ICA) was an important predictor of progression (p < 0.01); 6 of 8 patients (75%) with equivocal or mild contralateral disease progressed, whereas only 1 of 10 patients (10.0%) with no initial contralateral disease progressed to bilateral MMD. One patient had mild or equivocal MCA, ICA and ACA stenosis at the time of initial diagnosis and this patient progressed. Conclusions: Contralateral progression in the adult form occurs more commonly than previously reported. The presence of minor changes in the contralateral ACA, intracranial ICA and MCA is an important predictor of increased risk of progression. Patients with a completely normal angiogram on the contralateral side have a very low risk of progression.

A Genome-Wide Study of Moyamoya-Type Cerebrovascular Disease in the Korean Population

“…Our data corroborate previous reports from our group and others that many patients with unilateral moyamoya may develop disease on the non-affected side in a very delayed fashion or not at all 5,10,12,17) . The ability to accurately predict patients with unilateral moyamoya who are at greater risk for developing contralateral disease would be of substantial clinical advantage.…”

“…Patients with unilateral moyamoya disease can be difficult to treat, particularly regarding predicting the likelihood of subsequent progression to the contralateral side. The speed of progression of the vasculopathy associated with moymoya type vascular disease is extremely variable 5,10,12) . Copy number variation (CNV) refers to an intermediate-scale genomic change in segments greater than 1.0 kilo base pairs but typically less than 5 mega bases in length.…”

Moyamoya disease in pediatric patients: outcomes of neurosurgical interventions

“…The contralateral side should be closely monitored both clinically and angiographically, particularly if mild stenotic signs are visible given that progression of the disease is likely. 17 There are a number of advantages and disadvantages to each surgical option. Direct techniques require a specific set of conditions as well as a surgeon comfortable with the technical difficulty of such microanastomosis.…”

“…In our series, 75% of patients with equivocal or mild stenotic changes in the initially unaffected side eventually progressed to bilateral MMD at a mean follow-up time of 12.7 months. 17 Moyamoya disease is diagnosed and staged by using catheter angiography. The appearance and extent of stenosis, occlusion, and revascularization is divided into 6 distinct stages: 48 Stage 1, narrowing of the internal carotid arteries; Stage 2, initial appearance of moyamoya vessels; Stage 3, further definition of collateral vessels; Stage 4, minimization of collateral vessels; Stage 5, reduction of collateral vessels; and Stage 6, disappearance of collateral vessels.…”

Discovery of asymptomatic moyamoya arteriopathy in pediatric syndromic populations: radiographic and clinical progression

“…15,18,22 In addition, patients with unilateral moyamoya syndrome are frequently followed with serial imaging, because approximately one-third of unaffected hemispheres will ultimately progress to develop moyamoya. 10,19 This study exploits the availability of serial imaging studies in select populations of pediatric patients-those with NF1, SCD, or the unaffected hemisphere in children with unilateral moyamoya-to characterize the radiographic and clinical progression of incidentally found, asymptomatic moyamoya syndrome. The objectives of this work are to document the incidence of radiographic and clinical progression in previously asymptomatic children found to have moyamoya.…”