Leptomeningeal collateral and cerebral hemodynamics in patients with ICA and MCA steno-occlusion.

OBJECTIVES

The purpose of our study was to evaluate the correlation between fluid-attenuated inversion recovery (FLAIR) images of hyperintense vessel (HV), a representative of leptomeningeal vessels (LMVs), and cerebral vascular hemodynamic status in patients with steno-occlusive disease of the internal carotid artery (ICA) and middle cerebral artery (MCA).

METHODS

Sixty-eight patients with unilateral ICA or MCA stenosis or occlusion were enrolled. Correlations between hyperintense vessel (HV) on FLAIR images and hemodynamic status measured by quantitative single-photon emission computed tomography data were evaluated in four groups: affected (A) and non-affected (B) hemispheres in HV-positive patients, and affected (C) and non-affected (D) hemispheres in HV-negative patients.

RESULTS

The presence of HV was most frequently seen on affected hemispheres in patients with MCA and ICA occlusions. HV was significantly higher in the anterior communicating artery (AcomA) (-), posterior communicating artery (PcomA) (-) group than in other groups, which included either or both AcomA and PcomA (P = 0.008). The presence of HV had a significant correlation with transdural anastomosis (P = 0.046) and LMV (P = 1.64×10(-9)). No significant difference was observed in resting regional cerebral blood flow among the four groups. Vascular reserve in group A was significantly less compared to other groups (P = 0·021).

CONCLUSIONS

HV is related to the hemisphere with severe ICA and MCA steno-occlusion when the circle of Willis is insufficient. The HV-positive hemisphere on the steno-occlusive side shows a lower vascular reserve than that in the contralateral hemisphere or HV-negative hemispheres.