Moyamoya Syndrome in an Adolescent With Essential Thrombocythemia: Successful Intracranial Carotid Stent Placement

Abstract

Background. Essential Thrombocythemia (ET) is a chronic myeloproliferative disorder with increased frecuency of thrombotic events, including transient ischemic attacks and stroke. Moyamoya syndrome is a rare cerebrovascular disease characterized by progressive occlusion of intracerebral arteries with a typical “puff of smoke” angiographic pattern. We report the development of moyamoya syndrome in a patient with ET. Case Description. The patient is a 18-year-old female who presented at age 13 with recurrent TIAs. Persistent thrombocytosis was found, a diagnosis of ET was made and treatment with anagrelide was started. Despite normal platelet counts, she experienced recurrent TIAs and stroke. Severe stenosis of the supraclinoid segment of the left internal carotid artery (ICA) was found and moyamoya syndrome was diagnosed based on the characteristic angiographic pattern. An intracranial stent was placed in the left ICA and since then, she has had an uneventful outcome, with a 45-month follow-up. Conclusion. To our knowledge, the association between moyamoya and ET has not been previously reported. In addition, this is the first intracranial carotid stent implanted successfully in a patient with moyamoya.