Foramen spinosum and middle meningeal artery in moyamoya disease: Preliminary results of a pilot study

This study investigated whether the size of the middle cranial fossa foramina reflects the severity of moyamoya disease (MMD).It compared 20 adult patients managed without surgical revascularization with 2 age- and sex-matched controls. MR angiography scores were assigned by the severity of occlusive changes of the internal carotid artery, the middle cerebral artery, the anterior and the posterior cerebral arteries and the signals of the distal branches of these arteries. These scores were stratified into MR angiography grades (Houkin's grade: 1-4). The relationships between the Houkin's grade and the size of the foramen spinosum (FS), foramen ovale, carotid canal and middle meningeal artery (MMA) were evaluated.Simple regression analysis showed the correlation between the Houkin's grade and the bilateral FS (right, r = 0.56, p = 0.010; left, r = 0.46, p = 0.044) and MMA (right, r = 0.89, p = 0.0050; left, r = 0.47, p = 0.036). It also showed the correlation between the FS and MMA (right, r = 0.53, p = 0.018; left, r = 0.55, p = 0.013). There were no significant differences between the Houkin's grade, the size of the carotid canal and the foramen ovale.The larger FS and MMA on brain CT, which might be performed for patients suspected of intracranial lesions, could aid the diagnosis of MMD.