COMPARISON OF BOLUS AND CONSTANT INFUSION METHODS OF GADOLINIUM ADMINISTRATION IN MR-ANGIOGRAPHY

PURPOSE: To determine whether the method of delivery of gadolinium can alter optimal small-vessel detail in MR angiography. METHODS: Six hea lthy volunteers were studied with MR angiography using both a constant infusion and a bolus method of contrast administration to a total dos e of 0.1 mmol/kg. Both three-dimensional time-of-flight and 3-D phase- contrast techniques were used. RESULTS: Constant infusion did not prov e superior to bolus administration of contrast. With both techniques, gadolinium enhancement uniformly improved visualization of small vesse ls. Delay from the time of contrast administration to scan acquisition decreased vessel enhancement. CONCLUSIONS: Bolus administration of ga dolinium is sufficient to improve small vessel visualization with MR a ngiography. When a series of contrast-enhanced images is to be obtaine d, MR angiographic sequences should be obtained first.