Andreas Loening, MD/PhD

Variable Refocusing Flip Angle Single Shot Fast Spin Echo Imaging The most time consuming portion of most pelvic imaging protocols is the acquisition of T2-weighted imaging utilizing 2D fast-spin echo (FSE) sequences; this often requires 20-30 minutes of scanner time. Additionally, these 2D fast-spin echo sequences are often compromised by artifacts arising from respiratory motion and bowel peristalsis. Due to their greatly increased speed single shot fast spin echo (SSFSE) sequences have been proposed as a replacement for FSE as they essentially eliminate artifacts from motion, albeit at a cost of reduced signal-to-noise (SNR) and image blurring arising from T2-decay occurring during signal acquisition. We have incorporated variable refocusing flip angles into SSFSE (vrfSSFSE) in order to improve its image quality compared to conventional SSFSE as well as to further decrease imaging time via reductions in radiofrequency energy deposition (SAR constraints).

High-Resolution Post-Contrast Imaging for Tumor Staging in the Pelvis: As another approach to move away from the use of time-consuming and artifact-prone 2D fast-spin echo sequences in the pelvis, we have been exploring the relative diagnostic capability of a single high-resolution 3D post-contrast T1-weighted acquisition versus conventional multi-planar 2D FSE based imaging protocols. This high-resolution T1-weighted sequence allows reformation of arbitrary imaging planes retrospectively, removing the need for the acquisition of multiple separate planes of imaging as well as eliminating errors in acquisition plane prescription.