Significance of Magnetic Resonance Imaging (MRI) T2 Hyperintense Endo-Vessels Sign in Progressive Posterior Circulation Infarction.

BACKGROUND MRI FLAIR hyperintense vessels sign (FHVs) is a special imaging marker that plays a key role in acute infarction imaging and diagnosis. However, FHVs have not been studied in the context of progressive posterior circulation infarction (PPCI), and little is known about the association of hyperintense endo-vessels sign (HEVs) on transverse section MRI with infarction. Thus, our objective here was to investigate the clinical significance of transverse MRI T2 HEVs in patients with PPCI. MATERIAL AND METHODS In this retrospective, case-control study, we enrolled 100 consecutive posterior circulation infarction patients. All the patients underwent head MRI examinations on the onset day and the seventh day after admission. Neurologic deficits of the patients were assessed by the National Institutes of Health Stroke Scale (NIHSS) scores upon admission and after 7 days. Infarction volume on DWI was compared. RESULTS HEVs were detected in 25 of 37 patients in the PPCI group (67.6%) and 22 of 63 patients in the NPPCI group (34.9%). Logistic regression analysis showed that the proportion of HEVs in the PPCI group was higher than in the NPPCI group (P=0.007). Among all the patients, HEVs were detected in 15 of 18 patients (83.3%) with occlusion of the vertebral artery or basilar artery, and 17 of 23 (73.9%) showed severe stenosis. The proportion of vertebrobasilar artery occlusions in the PPCI group was higher than in the NPPCI group (P<0.05). MRI DWI showed that 20 patients had cerebellum infarction among 23 vertebral artery HEVs patients, and 14 patients had brainstem infarction among 15 basilar artery HEVs patients. All of the 9 vertebral and basilar artery HEVs patients had brainstem infarction. The increase in NIHSS scores from baseline to 7 days was significantly greater in patients with HEVs than in patients without HEVs in the PPCI group (P=0.002). The expansion of the infarction size from baseline to 7 days was significantly larger in patients with HEVs than in patients without HEVs in the PPCI group (P=0.037). CONCLUSIONS HEVs are frequently detected in patients with vertebrobasilar artery territory infarction, and they can be considered as a special imaging marker for vertebral artery and basilar artery occlusion and severe stenosis. HEVs can indicate whether or not posterior circulation infarction progresses and they may be an independent risk factor of PPCI.