SELECTED INDICATIONS FOR AND APPLICATIONS OF MAGNETIC-RESONANCE ANGIOGRAPHY IN CHILDREN

The purpose of this study was to investigate the efficacy and practica lity of magnetic resonance angiography (MRA) in evaluating pediatric c erebrovascular disorders. A retrospective evaluation was performed of MR angiograms in 20 pediatric patients with cerebrovascular pathology. When appropriate, comparisons were made with duplex ultrasonography o r conventional catheter angiography. MRA accurately assessed the paten cy of carotid reanastomoses in 8 babies who had previously undergone e xtracorporeal membrane oxygenation (ECMO). In 6 patients with moyamoya syndrome, MRA accurately evaluated stenotic intracranial carotid and circle of Willis arteries and progressive enlargement of the superfici al temporal and middle cerebral arteries after revascularization proce dures, and thus obviated the need for sequential angiograms. Thrombi a nd emboli were identified in 4 of 5 patients with symptoms and imaging evidence of an acute stroke. Two-dimensional time-of-flight MR venogr ams, acquired in both axial and coronal planes, were useful for preope rative venous mapping in a patient with an occipital encephalocele and detecting venoocclusive disease. MRA provided diagnostically useful i nformation in a spectrum of pediatric cerebrovascular disorders. It ca n be used as the initial vascular imaging modality for patients with i maging evidence of acute cerebrovascular event, to evaluate progressio n of chronic vasoocclusive disease, to evaluate vessel patency followi ng intracranial revascularization surgery, and for visualization of th e venous circulation.