Vertebral artery dominance contributes to basilar artery curvature and peri-vertebrobasilar junctional infarcts.
OBJECTIVE
The diameters of the vertebral arteries (VAs) are very often unequal. Therefore, this study investigated if unequal VA flow contributes to the development of basilar artery (BA) curvature and if it is a link to the laterality of pontine or cerebellar infarcts occurring around the vertebrobasilar junction.


METHODS
Radiological factors were analysed (infarct laterality, VA dominance, BA curvature and their directional relationships) in 91 patients with acute unilateral pontine or posterior inferior cerebellar artery (PICA) territory infarcts. The "dominant" VA side was defined as either that the VA was larger in diameter or the VA was connected with the BA in more of a straight line, if both VAs looked similar in diameter on CT angiography. Multiple regression analysis was performed to predict moderate to severe BA curvature.


RESULTS
The dominant VA was more frequent on the left side (p<0.01). Most patients had an opposite directional relationship between the dominant VA and BA curvature (p<0.01). Pontine infarcts were opposite to the side of BA curvature (p<0.01) and PICA infarcts were on the same side as the non-dominant VA side (p<0.01). The difference in VA diameters was the single independent predictor for moderate to severe BA curvature (OR per 1 mm, 2.70; 95% CI 1.22 to 5.98).


CONCLUSIONS
Unequal VA flow is an important haemodynamic contributor of BA curvature and development of peri-vertebrobasilar junctional infarcts.
Department of Neurology, Ajou University Medical Centre, Ajou University School of Medicine, Yongtong-Gu, Suwon-Si, Kyunggi-Do, South Korea. dacda@hanmail.net
J M
JM
Hong
C-S
CS
Chung
O Y
OY
Bang
S W
SW
Yong
I S
IS
Joo
K
K
Huh
D000368:Aged; D001488:Basilar Artery / Q000473:pathology* / Q000503:physiopathology*; D020526:Brain Stem Infarctions / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D016022:Case-Control Studies; D002531:Cerebellum / Q000098:blood supply / Q000473:pathology; D015331:Cohort Studies; D004108:Dilatation, Pathologic / Q000150:complications / Q000473:pathology / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow; D014711:Vertebral Artery / Q000473:pathology* / Q000503:physiopathology*; D014715:Vertebrobasilar Insufficiency / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology