Background: Moyamoya disease is one of the causes of higher brain dysfunction in younger patients. Fortunately, it may be possible to protect younger Moyamoya disease patients from brain dysfunction via surgical manoeuvres.
Aim: Our group retrospectively analysed the correlation between preoperative positron emission tomography data and the intelligence quotient scores of 60 Japanese Moyamoya disease patients (age range 9-64).
Method: All patients underwent a quantitative measurement of the cerebral metabolic rate of oxygen by inhalation of C(15)O(2) and (15)O(2) gas with positron emission tomography. The data was analysed using spm99 software to determine the cerebral regions in which regional cerebral metabolic rate of oxygen was significantly correlated with full-scale intelligence quotient, verbal intelligence quotient, or performance intelligence quotient measured using the Wechsler intelligence scale.
Results: All scores (full-scale intelligence quotient, verbal intelligence quotient, and performance intelligence quotient) showed significant positive correlations with the cerebral metabolic rate of oxygen in the lower part of the bilateral frontal lobe, the right anterior temporal lobe, and the medial occipital lobe. The verbal intelligence quotient was significantly and positively correlated with the cerebral metabolic rate of oxygen in the left inferior frontal lobe, including Broca's area. Infarcted lesions in the left posterior temporal lobe and the right upper frontal lobe influenced the decline of all of the intelligence quotient scores measured.
Conclusion: The present analysis indicates that the higher brain function of Moyamoya disease patients tends to be affected by the cerebral metabolism of specific regions. This information may be useful in seeking optimal clinical management to preserve higher brain function in patients with Moyamoya disease.