Background: Clinical syndromes secondary to infarcts in the distal basilar artery (BA) area have been described as “top of the basilar” (TOB) syndrome. However, in the era of advanced imaging technology, it has been realized that the clinical and imaging features are quite diverse in patients with distal BA occlusion. The aim of the present study was to investigate the patterns and clinical outcomes of TOB assessed with modern images and categorize TOBs accordingly. Additionally, we examined the possible influence of the posterior communicating artery (PcoA) on the patterns of TOB. Methods: Patients with distal BA occlusion on magnetic resonance angiography were categorized as TOB-A, and those with multiple lesions in the distal BA territory on diffusion-weighted magnetic resonance imaging as TOB-L. Patients with angiographically and lesion distribution-defined TOB were classified as having TOB-A&L; those with angiographically defined TOB as having TOB-A without TOB-L; and those with lesion distribution-defined TOB as having TOB-L without TOB-A. The PcoA was categorized as “textbook-type” (good P1) and “fetal-type” (absent P1). Factors associated with unfavorable short-term outcomes (modified Rankin Scale 5–6 at discharge), and 1-year and long-term mortalities, were assessed. Results: Of 1,466 patients with ischemic stroke in the posterior circulation who were admitted to Asan Medical Center within 24 h of symptom onset, 124 (8.5%) had TOB, including 45 with TOB-A&L, 44 with TOB-A, and 35 with TOB-L. NIHSS scores (21 [9.5–26] vs. 6 [3–11.5] vs. 6 [3–9]; p < 0.01) and rates of motor deficit (75.6 vs. 54.5 vs. 34.4%; p < 0.01), concomitant pontine lesions (17.8 vs. 25.0 vs. 2.9%; p < 0.01), PcoA presence (44.4 vs. 68.2 vs. 25.7%; p < 0.01), and unfavorable short-term outcomes (62.2 vs. 25.0 vs. 14.3%; p < 0.01) differed significantly in the 3 patient groups. Multivariate analysis showed that textbook-type PcoA was independently associated with a lower frequency of unfavorable short-term outcomes (OR 0.15, 95% CI 0.03–0.70). Reperfusion therapy (hazard ratio [HR] 0.25, 95% CI 0.07–0.89) and the presence of textbook-type PcoA (HR 0.20, 95% CI 0.05–0.90) were associated with a lower 1-year mortality rate after stroke. Conclusion: Patterns and clinical outcomes of TOB vary and are affected by the hemodynamic status of the arterial system, such as BA recanalization and the presence of textbook-type PcoA.

1.
Caplan LR: “Top of the basilar” syndrome. Neurology 1980; 30: 72–79.
2.
Sato M, Tanaka S, Kohama A: “Top of the basilar” syndrome: clinico-radiological evaluation. Neuroradiology 1987; 29: 354–359.
3.
Barkhof F, Valk J: “Top of the basilar” syndrome: a comparison of clinical and MR findings. Neuroradiology 1988; 30: 293–298.
4.
Mehler MF: Reversible rostral basilar artery syndrome. Arch Intern Med 1988; 148: 166–169.
5.
Finocchi C, Del Sette M, Croce R, Giberti L, Serrati C, Gandolfo C: Bilateral ophthalmoplegia: an unusual sign of top of the basilar artery syndrome. Ital J Neurol Sci 1996; 17: 301–304.
6.
Arai D, Nakajima M: “Top of the basilar” occlusion causing bilateral internuclear ophthalmoplegia. Intern Med 2011; 50: 527–528.
7.
Spengos K, Wohrle JC, Tsivgoulis G, Stouraitis G, Vemmos K, Zis V: Bilateral paramedian midbrain infarct: an uncommon variant of the “top of the basilar” syndrome. J Neurol Neurosurg Psychiatry 2005; 76: 742–743.
8.
Silverman IE, Geschwind MD, Vornov JJ: Cerebellar top-of-the-basilar syndrome. Clin Neurol Neurosurg 1998; 100: 296–298.
9.
Liebeskind DS: Collateral circulation. Stroke 2003; 34: 2279–2284.
10.
Schomer DF, Marks MP, Steinberg GK, Johnstone IM, Boothroyd DB, Ross MR, Pelc NJ, Enzmann DR: The anatomy of the posterior communicating artery as a risk factor for ischemic cerebral infarction. N Engl J Med 1994; 330: 1565–1570.
11.
Hong JM, Choi JY, Lee JH, Yong SW, Bang OY, Joo IS, Huh K: Impact of posterior communicating artery on basilar artery steno-occlusive disease. J Neurol Neurosurg Psychiatry 2009; 80: 1390–1393.
12.
Adams HP Jr, Bendixen BH, Kappelle LJ, Biller J, Love BB, Gordon DL, Marsh EE 3rd: Classification of subtype of acute ischemic stroke. Definitions for use in a multicenter clinical trial. Toast. Trial of org 10172 in acute stroke treatment. Stroke 1993; 24: 35–41.
13.
Mehler MF: The rostral basilar artery syndrome: diagnosis, etiology, prognosis. Neurology 1989; 39: 9–16.
14.
Lee DK, Kim JS, Kwon SU, Yoo SH, Kang DW: Lesion patterns and stroke mechanism in atherosclerotic middle cerebral artery disease: early diffusion-weighted imaging study. Stroke 2005; 36: 2583–2588.
15.
Tanaka H, Fujita N, Enoki T, Matsumoto K, Watanabe Y, Murase K, Nakamura H: Relationship between variations in the circle of willis and flow rates in internal carotid and basilar arteries determined by means of magnetic resonance imaging with semiautomated lumen segmentation: reference data from 125 healthy volunteers. AJNR Am J Neuroradiol 2006; 27: 1770–1775.
16.
Wentland AL, Rowley HA, Vigen KK, Field AS: Fetal origin of the posterior cerebral artery produces left-right asymmetry on perfusion imaging. AJNR Am J Neuroradiol 2010; 31: 448–453.
17.
van Swieten JC, Koudstaal PJ, Visser MC, Schouten HJ, van Gijn J: Interobserver agreement for the assessment of handicap in stroke patients. Stroke 1988; 19: 604–607.
18.
Qureshi AI, Chaudhry SA, Sapkota BL, Rodriguez GJ, Suri MF: Discharge destination as a surrogate for modified rankin scale defined outcomes at 3- and 12-months poststroke among stroke survivors. Arch Phys Med Rehabil 2012; 93: 1408–1413.e1401.
19.
Organization WH: International Statistical Classification of Diseases and Related Health Problems. Tenth Revision. Vol. 1: Tabular List (1992); vol. 2: Instruction Manual (1993); vol. 3: Index (1994). Geneva, WHO, 1992.
20.
Vernino S, Brown RD Jr, Sejvar JJ, Sicks JD, Petty GW, O’Fallon WM: Cause-specific mortality after first cerebral infarction: a population-based study. Stroke 2003; 34: 1828–1832.
21.
Kim BJ, Park JM, Kang K, Lee SJ, Ko Y, Kim JG, Cha JK, Kim DH, Nah HW, Han MK, Park TH, Park SS, Lee KB, Lee J, Hong KS, Cho YJ, Lee BC, Yu KH, Oh MS, Kim DE, Ryu WS, Cho KH, Kim JT, Choi JC, Kim WJ, Shin DI, Yeo MJ, Sohn SI, Hong JH, Lee J, Lee JS, Yoon BW, Bae HJ: Case characteristics, hyperacute treatment, and outcome information from the clinical research center for stroke-fifth division registry in South Korea. J Stroke 2015; 17: 38–53.
22.
Ferbert A, Bruckmann H, Drummen R: Clinical features of proven basilar artery occlusion. Stroke 1990; 21: 1135–1142.
23.
Santalucia P: Extended infarcts in the vertebrobasilar territory. Front Neurol Neurosci 2012; 30: 176–180.
24.
von Campe G, Regli F, Bogousslavsky J: Heralding manifestations of basilar artery occlusion with lethal or severe stroke. J Neurol Neurosurg Psychiatry 2003; 74: 1621–1626.
25.
Hong KS, Ko SB, Yu KH, Jung C, Park SQ, Kim BM, Chang CH, Bae HJ, Heo JH, Oh CW, Lee BC, Kim BT, Kim BS, Chung CS, Yoon BW, Rha JH: Update of the korean clinical practice guidelines for endovascular recanalization therapy in patients with acute ischemic stroke. J Stroke 2016; 18: 102–113.
26.
Mattle HP, Arnold M, Lindsberg PJ, Schonewille WJ, Schroth G: Basilar artery occlusion. Lancet Neurol 2011; 10: 1002–1014.
27.
Bivard A, Lin L, Parsonsb MW: Review of stroke thrombolytics. J Stroke 2013; 15: 90–98.
28.
Ovbiagele B, Saver JL: Day-90 acute ischemic stroke outcomes can be derived from early functional activity level. Cerebrovasc Dis 2010; 29: 50–56.
29.
Ovbiagele B, Lyden PD, Saver JL: Disability status at 1 month is a reliable proxy for final ischemic stroke outcome. Neurology 2010; 75: 688–692.
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