Decreased hyperintense vessels on FLAIR images after endovascular recanalization of symptomatic internal carotid artery occlusion

Hyperintense Vessels, Collateralization, and Functional Outcome in Patients With Stroke Receiving Endovascular Treatment

“…10,[12][13][14] Although most studies agree that the presence of FHV in stroke is associated with large vessel occlusion, 14 results on the clinical relevance of this MRI sign are inconsistent. Some studies found that FHVs are associated with more severe cerebral hypoperfusion and worse functional recovery poststroke and postulated that FHVs represent insufficient collateralization.…”

“…Previous studies that used advanced imaging techniques (such as digital subtraction angiography) in selected stroke cohorts with homogenous vessel occlusion also found FHV to be associated with high collateral status. 13,25 Thus, we think that this apparent discrepancy can be explained by comparison of heterogeneous stroke patients with various vessel occlusions, lack of systematic FHV quantification systems, and incomprehensive imaging data to assess collateral status.…”

“…Although some studies found that FHVs are associated with poor functional recovery suggesting insufficient collateralization, [14][15][16]24 others found precisely the opposite suggesting FHV to be indicative of high collateral grades and favorable treatment response. 10,13,18 Interestingly, those studies that found FHV to be associated with poor functional recovery were performed in smaller, heterogeneous cohorts and used merely clinical parameters or perfusion imaging to assume collateral status. A direct association between FHV and collateral status assessed via angiography was lacking in these studies, justifying the comparison in a large and homogenous stroke cohort in relation to functional outcome data.…”

“…The median age of the cohort was 74 years (interquartile range [IQR], 64-79), and 45% of patients were men. The median NIHSS score was 14 (10)(11)(12)(13)(14)(15)(16)(17)(18)(19). The median DWI-ASPECTS was 7 (5-8), and 17% of the DWI lesions were positive on FLAIR imaging.…”

“…The association remained statistically significant with an OR=4.4 (1.1-18.3) in additional multivariable analyses after adjusting for possible confounders (Table II in Clinical outcome parameters at discharge did not differ in both cohorts. In the pooled cohort, patients with lower FHV-ASPECTS were more likely to have a lower NIHSS score (median NIHSS, 4; IQR, 1-9) at discharge, compared with patients with higher FHV-ASPECTS (median NIHSS, 8; IQR, [3][4][5][6][7][8][9][10][11][12][13][14][15]. Frequency of good functional outcome at discharge was significantly higher in low FHV-ASPECTS patients than in high FHV-ASPECTS patients (43% versus 23%; P=0.032; Table 1).…”