Dominant ipsilateral posterior cerebral artery on magnetic resonance angiography in acute ischemic stroke.

BACKGROUND

In acute infarction involving the anterior circulation, the ipsilateral posterior cerebral artery (PCA) often appears to be longer than the contralateral PCA on magnetic resonance angiography. We described this finding as dominant ipsilateral PCA (DIPCA). We sought to find the frequency of DIPCA and its predictors.

METHODS

We recruited 164 consecutive individuals with acute infarct involving the anterior circulation, and analyzed their radiological and clinical features.

RESULTS

DIPCA was noted in 27 patients (16.5%). It was more frequent in patients with than in patients without steno-occlusive disease of the ipsilateral anterior circulation (30.5 vs. 2.4%, p < 0.001). Multivariate analysis revealed a significant relationship between the severity of arterial lesions in the ipsilateral anterior circulation and DIPCA (p = 0.039).

CONCLUSIONS

DIPCA may reflect increased leptomeningeal collateral flow via the ipsilateral PCA, and its development may be dependent on the stenotic anterior circulation.