Pulmonary Vein Imaging with Unenhanced Three-dimensional Balanced Steady-State Free Precession MR Angiography: Initial Clinical Evaluation 1 Christopher J. Franc ¸ois, MD David Tuite, MD Vibhas Deshpande, PhD Renate Jerecic, PhD Peter Weale, PhD James C. Carr, MD Purpose: To determine whether unenhanced magnetic resonance (MR) angiography performed with a three-dimensional (3D) segmented steady-state free precession (SSFP) se- quence would be an alternative to contrast material– en- hanced MR angiography for evaluating pulmonary veins (PVs) prior to and following radiofrequency (RF) ablation for atrial fibrillation. Materials and Methods: MR angiographic examinations of PVs, performed in 20 patients (nine men, 11 women; mean age, 56.4 years  12.7 [standard deviation]), were retrospectively reviewed according to an institutional review board–approved pro- tocol. The number of PVs and their orthogonal measure- ments obtained from the 3D SSFP images were compared with those obtained from contrast-enhanced MR angiogra- phy. Signal-to-noise and contrast-to-noise ratios were also compared. Qualitative assessment of both techniques was performed by independent reviewers who scored the im- age quality (on a scale of 1 to 5) on the basis of PV conspicuity. The presence of cardiac and extracardiac pathologic indicators was also determined. Bland-Altman and Wilcoxon signed rank statistical analyses were per- formed. Results: The mean difference in PV diameter measurements be- tween contrast-enhanced MR angiography and 3D SSFP was -0.02 cm  0.25. Signal-to-noise and contrast-to- noise ratios were higher for 3D SSFP images than for contrast-enhanced MR angiograms. Qualitatively, there was no significant difference in PV conspicuity between the techniques. Noncardiac pathologic indicators were de- tected in 10 of 20 patients on 3D SSFP images but not on contrast-enhanced MR angiograms. Conclusion: Unenhanced PV MR angiography performed by using a free-breathing 3D SSFP technique is as accurate as con- trast-enhanced MR angiography for measuring PV diame- ter. This technique can be used for patients in whom contrast-enhanced computed tomographic or MR angiog- raphy is contraindicated and may be sufficient in all pa- tients.  RSNA, 2009 1 From the Department of Radiology, Northwestern Uni- versity, Chicago, Ill (C.J.F., D.T., J.C.C.); and MR Re- search and Development, Siemens Medical Solutions USA, Malvern, Pa (V.D., R.J., P.W.). From the 2007 RSNA Annual Meeting. Received December 14, 2007; revision requested February 21, 2008; revision received August 5; accepted August 11; final version accepted September 2. Address correspondence to C.J.F., Department of Radi- ology, University of Wisconsin–Madison, 600 Highland Ave, Madison, WI 53792-3252 (e-mail: cfrancois @uwhealth.org ).  RSNA, 2009 ORIGINAL RESEARCH  THORACIC IMAGING 932 radiology.rsnajnls.org ▪ Radiology: Volume 250: Number 3—March 2009 Note: This copy is for your personal non-commercial use only. To order presentation-ready copies for distribution to your colleagues or clients, contact us at www.rsna.org/rsnarights.