SU-E-I-61: An Efficient and Practical MR Flow Quantification Quality Assurance Method

Abstract

Purpose: To develop and validate a novel flow quantification quality assurance (QA) method based on a multi-directional flow phantom driven by a power injector and a fast measurement protocol. Methods: An improved MR flow phantom driven power injector was designed and constructed by immersing a 3D loop of acrylic tubes in a bath stationary saline. A power injector equipped with clinical MR scanner can be used to deliver 60 ml of saline at a nominal flow rate of 2ml/sec. A fast 2D phase contrast flow quantification protocols was optimized to measure the through-plane flow rate in three orthogonal orientations in less than 24 sec. At the same time, the actual amount of saline injected was measured to calibrate the output of power injector and to determine the true flow rate more accurately. Such method was tested and evaluated on a 3.0T clinical MR scanner (Siemens TIM Trio). Results: Eight repeat flow quantification QA measurements and power injector output calibration were performed. The measured flow rates were +2.31±0.05 ml/s and −2.21±0.10 ml/s in the H/F direction, +2.37±0.11 ml/s and −2.68±0.15 ml/s in the A/P direction and +2.35±0.11 ml/s and −2.63±0.06 ml/s in the R/L direction. The calibrated true flow rate was 1.937±0.004 ml/s. The flow quantifications in all direction are highly reproducible, but significantly different from the reference value. Conclusion: A novel method of MR flow quantification quality assurance using a advanced flow phantom driven by a power injector combined with an optimized fast measurement protocol was validated. Since most clinical MR scanners are already equipped with a power injector and the entire procedure is very quick and simple, there should be little barrier for its wide-spread implementation. Research Support from Siemens