Effect of contrast material (Levovist) infusion on peak systolic velocity in middle cerebral artery using transcranial color-coded duplex sonography

Abstract

It is of crucial importance to predict the presence of stenosis in cerebral artery before occurrence of a stroke. To determine stenosis in the middle cerebral artery (MCA), we examined the effect of contrast agent (Levovist) infusion on transcranial color-coded duplex sonography (TCCD). TCCD was performed in 24 patients with MCA stenosis determined by angiography and/or magnetic resonance angiography, and 42 patients without MCA stenosis were also examined as the control group. All patients participated to assess whether an intravenous infusion of contrast agent has some influence on the peak systolic velocity (PSV) measured along the MCA. Videotaping was initiated at the administration of contrast material and continued until contrast was no longer visible in the vessels. PSV values in normal and stenotic vessels were compared. We found that PSVs were significantly higher in the stenosis group than in the control group. Difference between precontrast and postcontrast infusion was significantly greater in the stenosis group than in the control group (p < 0.05). We conclude that PSV tends to be underestimate in poor visualization of vessels. To improve accuracy of PSV measurement, contrast enhancement material should be used.