Equilibrium Res Vol. (3) Vertebrobasilar Insufficiency Toshiaki Yamanaka Department of Otolaryngology-Head and Neck Surgery, Nara Medical University School of Medicine Vertebrobasilar insufficiency (VBI) is caused by transient ischemia in the brainstem including the vestibular nucleus due to impaired vertebrobasilar arterial flow. The most common causes of VBI are atherosclerosis, which can block posterior circulation supplying the brain stem, and embolisms which arise from the heart and proximal vertebral and basilar arteries due to arrhythmia, as well as hemodynamic disorders associated with changes in blood pressure. VBI is frequently associated with vertigo and disequilibrium as primary symptoms accompanied by neurologic symptoms and signs involving double vision, loss of vision, gait ataxia, face and limb numbness, weakness, dysarthria and oropharyngeal dysfunction. Posterior circulation strokes may induce fluctuating symptoms and signs with time depending on which area is ischemic. It is crucial to examine the pathological condition of the vessels in the vertebrobasilar system to evaluate blood flow hemodynamics and vascular morphology in patients experiencing episodes of VBI with Doppler ultrasonography and a vascular imaging technique such as (Magnetic Resonance) MR and (Computed Tomography) CT angiography. Cerebrovascular circulation and metabolism-improving agents, antiplatelet agents, etc., are usually used to treat VBI VBI should be considered during the differential diagnosis of patients with recurrent vertigo and require an early detection. Therefore, VBI might require careful follow-up and treatment for preventing the progression of vertigo and other neurological deficits in the vertebrobasilar arterial region. Key words: VBI, transient ischemic attack, vertebral artery, basilar artery, vertigo Vertebrobasilar InsufficiencyVBI ( 117 )
Equilibrium Res Vol. (3) CT VBI VBI VBI VBI Transient Ischemic attacktia VBI TIA TIA VBI TIA TIA ( 118 )
Equilibrium Res Vol. (3) A 1 24 10 1 5 20 5 22% 22% 23% 12% 6% 12% 3% B / / 13 % 17 % / / 41 % 29 % C ( D ( VBI VBI Bow hunter s Stroke Power VBI VBI ( 119 )
Equilibrium Res Vol. (3) VBI VBI Definite VB-TIA CT VBI Definite MRA/CTA VBI Probable VBI Possible 1 2 3 35.1% 54.4% 10.5% (20) (31) (6) 1.8% 1.8% 1.8% 5.3% 8.8% 7.0% 5.3% 5.3% 3.5% 5.3% 7.0% 14.0% 12.3% 12.3% 19.3% 29.8% 38.6% VBI TIA TIA CT TIA VBI Definite VBI VBI VBI ( 120 )
Equilibrium Res Vol. (3) 24 17 14 1 6 2 5 0 23% 16% 24 17 14 13 36 6 2 1 2 2 1 0 VBI Magnetic Resonance AngiographyMRA/Computed Tomography AngiographyCTA VBI Probable VBI TIA VBI Possible VBI TIA TIA TIA MRI diffusion weighted imagedwitia TIA MRI MRI DWI DWI TIA VBI TIA VBI VBI VBI VBI VBI ( 121 )
Equilibrium Res Vol. (3) TIA TIA VBI TIA MRI DWI DWI TIA VBI VBI VBI VBI VBI VBI VBI VBI CT CT VBI MRIMRI DWI DWI TIA MRA/CTA VBI ( 122 )
Equilibrium Res Vol. (3) VBI MRA MRA VBI VBI VBI VBI VBI VBI VBI TIA ABCD D VBI VBI ( 123 )
Equilibrium Res Vol. (3) / B12ATP VBI VBI TIA TIA VBI VBI B12ATP ( 124 )
Equilibrium Res Vol. (3) VBI PGE 1 VBI Vertebro-basilar insufficiency Equilibrium Res Suppl 11: 5152, 1995 Baloh RW: Vertebrobasilar insufficiency and stroke. Otolaryngol Head Neck Surg 112: 114117, 1995 ENT p. 285292 VBI TIA ER pp 223229 Yamanaka T, Sawai Y, Hosoi H: Bilateral subclavian steal syndrome with vertigo, Auris Nasus Larynx 41: 307309, 2014 Special report from National Institute of Neurological Disorders and Stroke. Classification of cerebrovascular diseases III. Stroke 21: 637676, 1990 p. 314321 Grad A, Baloh RW: Vertigo of Vascular Origin: clinical and electronystagmographic features in 84 cases. Arch Neurol 46: 281284, 1989 Gomez CR, Cruz-Flores S, Malkoff MD, et al.: Isolated vertigo as a manifestation of vertebrobasilar ischemia. Neurology 47: 9497, 1996 Emergency Johnston SC, Rothwell PM, Nguyen-Huynh MN, et al. : Validation and refinement of scores to predict very early stroke risk after transient ischaemic attack. Lancet 369: 283 292, 2007 Yamanaka T, Fukuda T, Shirota S, et al.: The prevalence and characteristics of metabolic syndrome in patients with vertigo. PLoS ONE, doi: 10.1371/journal. pone. 0080176, 2013 CVD ER pp 254258 Albers GW, Caplan LR, Easton JD, et al.: Transient Ischemic Attack-Proposal for a new definition. N Engl J Med 347: 1713 1716, 2002 Easton JD, Saver CJ, Albers GW, et al.: Definition and Evaluation of Transient Ischemic Attack: A Scientific Statement of Healthcare Professionals From the American Heart Asso- ( 125 )
Equilibrium Res Vol. (3) ciation/american Stroke Association Stroke Council; Council on Cardiovascular Surgery and Anesthesia; Council of Cardiovascular Radiology and Intervention; Council on Cardiovascular Nursing; and the Interdisciplinary Council on Peripheral Vascular Disease. Stroke 40: 22762293, 2009 TIA TIA TIA pp 1113 Yamasoba T, Kikuchi S, Higo R: Deafness associated with vertebrobasilar insufficiency. J Neurol Sci 187: 6975, 2001 Equilibrium Res 62 : 339 341, 2003 Yamanaka T, Yamamoto T, Matsunaga T: Vestibular neuronal function of cats following unilateral vertebral artery occlusion. Acta Otolaryngol. Suppl, 533: 2629, 1998 MB ENT 83: 6674, 2007 QureshiAI,ZiaiWC,YahiaAM,etal.:Strokefree survival and its determinants in patients with symptomatic vertebrobasilar stenosis: a multicenter study. Neurosurg 52: 10331039, 2003 MB ENT 53: 116121, 2005 Yamanaka T, Murai T, Sawai Y, et al.: The effect of prostaglandin E on brainstem blood flow disturbance in an animal model of vertebrobasilar insufficiency, Eur Arch Otorhinolaryngol 271: 947951, 2014 ( 126 )