A Rare Case of Carotid Artery Dissection and Vertebral Aneurysm Associated with Essential ThrombocythemiaShunyu Zhang1, #, Ting Zhang1, #, Xingdong Deng1,2, #, Nailiang Zang1, Pingyi Xu1, Zuojun Tian1, *1 Department of Neurology, the First Affiliated Hospital of Guangzhou Medical University.2 Department of Neurology, the Second Affiliated Hospital of Xinjiang Medical University.* Corresponding authors:Zuojun Tian , Department of Neurology, the First Affiliated Hospital of Guangzhou Medical University. Yanjiang Road 150#, Yuexiu District, Guangzhou, 510230, China, Email: tianzuojun9@163.com, Tel: (+86) 02083062721# These authors contributed equally to this work.