Contralateral progression and its risk factor in surgically treated unilateral adult moyamoya disease with a review of pertinent literature.

BACKGROUND

The fate of the contralateral unaffected side of the surgically treated unilateral moyamoya disease (MMD) in adults has not been well described due to the limited number of cases and the heterogeneous ages and treatment methods. The aim of this study was to evaluate the contralateral angiographic progression rate and its risk factors in homogeneous adult MMD patients who underwent surgical revascularization, with a review of pertinent literature.

METHODS

Forty-one surgically treated unilateral MMD patients were retrospectively evaluated. We reviewed medical and radiological records including data on gender, age, hypertension (HTN), smoking, familial MMD, presenting symptom, surgical method, Suzuki stage, and contralateral progression. Then, we conducted univariate and multivariate analyses to determine risk factors.

RESULTS

Six of the 41 cases (14.6%) exhibited contralateral progression during the mean follow-up of 34 months. Four of those six patients (66.7%) were asymptomatic. Additional revascularization surgery was performed in the two symptomatic patients. The presence of a contralateral angiographic abnormality on initial angiography was a statistically significant risk factor for progression (OR, 49.00; p = 0.04). Younger age at diagnosis (32.7 ± 7.8 years in progression group vs. 42.5 ± 10.3 years in non-progression group, p = 0.046) was statistically significant in the univariate analysis, but age was not a significant factor in the multivariate analysis (p = 0.82). Other variables, such as gender (p = 0.13), HTN (p = 0.24), smoking (p = 0.47), and familial MMD (p = 0.20), did not show statistical significance.

CONCLUSIONS

The presence of a contralateral angiographic abnormality on initial angiography was a significant risk factor for progression in surgically treated unilateral adult MMD. Consequently, patients with contralateral abnormalities should be monitored closely.