Kissing balloon treatment for stenosis of the internal and external carotid artery orifice associated with moyamoya disease: illustrative case.

backgroundMoyamoya disease (MMD) is a cerebrovascular disorder that is characterized by progressive stenosis in the terminal portions of the internal carotid artery (ICA). Although a substantial number of patients with MMD exhibit stenosis of the ICA orifice (ICAO), it infrequently occurs in patients with MMD with external carotid artery orifice (ECAO) stenosis. OBSERVATIONS: A 48-year-old female with no past medical history presented to the authors' hospital with right hemiparesis and motor aphasia. Head magnetic resonance imaging revealed bilateral acute cerebral infarctions in the left frontal lobe, and magnetic resonance angiography demonstrated bilateral ICA terminal stenosis. Digital subtraction angiography revealed severe stenosis in the right ICAO and left ICAO and ECAO, as well as bilateral ICA terminal stenosis; therefore, the authors diagnosed this case as MMD. They first performed percutaneous transluminal angioplasty (PTA) using the kissing balloon technique (KBT) for the stenosis in the left ICAO and ECAO, followed by PTA for the right ICAO stenosis. After that, they performed bilateral direct and indirect revascularization. LESSONS: The authors present a rare case of MMD with stenosis of the ICAO and ECAO, which was treated with PTA using the KBT, followed by direct and indirect revascularization. Although the strategy is controversial in terms of which treatment should be performed first, this method of anterograde revascularization was a promising strategy. https://thejns.org/doi/10.3171/CASE24425.