text: There isn't classification about the VBI yet, but there are three phenotypes of the basilar artery occlusion depending on the modal of initial symptoms.
  phenotype 1: patients present progressive brain stemsymptoms(for example: vertigo, doublevision, dysarthria, hemiparesis, or paresthesia) without any prodromal symptoms.
  phenotype 2: patients present nonspeciﬁc, such as nausea, tinnitus, hearing loss, and vertigo, which can precede the onset of the monophasic, progressive deﬁcits by days, but typically by several weeks.
  phenotype 3: patients present symptoms with onset of severe, often bilateral motor weakness, ophtalmoplegia, and coma.  The patients may have a severe outcome if basilar artery cannot be recanalized fast.
option_0: Vertebrobasilar insufficiency classification
option_1: Aortitis classification
option_2: Vertebrobasilar insufficiency laboratory findings
option_3: Acoustic neuroma classification
option_4: Vertebrobasilar insufficiency MRI
option_5: Cerebral aneurysm classification
option_6: Glaucoma classification
option_7: Ganglioneuroma classification