Time-resolved projection MRA: clinical application in intracranial vascular malformations.

We report preliminary results of imaging intracranial vascular malformations with time-resolved projection MRA after a bolus injection of contrast median before and after endovascular treatment. Projection angiograms are acquired with a slice-selective snapshot FLASH sequence with a time resolution of two images per second, 40-60 images being acquired consecutively after bolus injection of 15 ml Gd-DTPA. Postprocessing of images in 2D projection MRA by correlation analysis offers several advantages with significant improvement of signal-to-noise, leading to adequate anatomical resolution. Subsecond projection MRA is a reliable technique for imaging intracranial vessels and gives information about the haemodynamics of vascular malformations.