End-expiration, 21-second breathhold, three-dimensional magnetic resonance (MR) cholangiopancreatography (MRCP) was developed with segmented echo-planar imaging. In 15 healthy subjects and 14 randomly selected patients undergoing liver studies, three-dimensional MRCP images were obtained and volume rendered. In 15 (100%) healthy subjects and 13 (93%) patients, clear depiction of biliary, hepatic, and pancreatic ducts (with lumen diameter of at least 2 mm) was possible with good signal-to-noise ratio.Fast magnetic resonance (MR) imaging techniques exploit the long T2 exhibited by biliary and hepatic fluids (Ͼ1.5 seconds) to produce high-quality, two-and three-dimensional (3D) MR cholangiopancreatographic (MRCP) images without the addition of contrast media. In initial attempts to visualize the entire biliary tree, steady-state free-precession imaging was used, with high contrast over several breath holds (1,2). However, steady-state free-precession sequences proved too sensitive to signal loss from magnetic susceptibility, fluid motion, and pulsation. More robustness is now possible with rapid acquisition with relaxation enhancement (RARE) (3) and fast spin-echo (SE) (4) sequences. With long effective echo times, only fluid-filled compartments are observed with nearly complete background suppression and minimal sensitivity to motion and signal loss due to magnetic susceptibility. Many techniques have been evaluated that differ in coverage, spatial resolution, signal-tonoise ratio (SNR), examination length, and patient cooperation. These techniques include breath-hold, two-dimensional, single-shot, single-projection, thick-section RARE (5); breath-hold, twodimensional, multisection, half-Fourier RARE (HASTE; Siemens Medical Systems, Erlangen, Germany) (6); and fast SE (7,8) and respiratory-gated 3D fast SE (9,10). The RARE and half-Fourier RARE techniques have been widely explored and accepted as techniques of choice for diagnostic MRCP.Nonetheless, the availability of a 3D fast SE technique would enable operatorindependent imaging, large-volume coverage, examinations with maximum patient comfort, and the possibility of data reformation and volume rendering. Unfortunately, imaging time can still be excessive and results hampered by blurring from remnant respiratory motion. By combining 3D fast SE and segmented echo-planar imaging (11), we attempted to increase SNR and resolution in shorter imaging time, equivalent to an increase in data density, to obtain breath-hold volume images of the entire hepatic, bile, and pancreatic duct systems with the advantages of 3D acquisitions. Therefore, we performed this study to illustrate the potential of this new acquisition technique. Materials and Methods Patient PopulationThe study population included 15 healthy volunteers (six men, nine women; age range, 21-34 years). In addition, 14
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