Rapid noncontrast MRI screening for iliac and left renal vein compression: A practical bSSFP technique

ObjectivesTo describe a rapid, widely available, noncontrast magnetic resonance imaging (MRI) technique for first-line morphologic assessment of suspected iliac and left renal vein compression in patients with symptoms potentially related to pelvic venous disorders.MethodsWe use a two-stack axial two-dimensional balanced steady-state free precession (bSSFP) acquisition extending from the renal hila through the iliac bifurcation. The sequence is available on major MRI platforms as TrueFISP (Siemens), FIESTA (GE), or bTFE (Philips). Typical 1.5-T parameters are TR/TE 3.0-3.8/1.5-1.9 ms, flip angle 60-80°, 5-mm slice thickness, and 1.3-1.6-mm in-plane resolution. Localized shimming is performed for each stack.ResultsThe abbreviated examination requires approximately 10 minutes of scanner time, including planning and breath-hold acquisitions. It depicts the site and degree of iliac or left renal vein compression and demonstrates collateral pathways that may support physiologic relevance. Morphologic abnormalities are interpreted in the clinical context and are not considered diagnostic of a symptomatic syndrome in isolation.ConclusionsA short bSSFP protocol can provide a practical, radiation-free gateway examination when comprehensive MR venography is unavailable or undesirable. It may facilitate appropriate referral and procedural planning, while invasive assessment, including intravascular ultrasound when stenting is contemplated, remains necessary in selected patients.