High‐spatial‐resolution three‐dimensional MR cholangiography using a high‐sampling‐efficiency technique (SPACE) at 3T: Comparison with the conventional constant flip angle sequence in healthy volunteers

Abstract

Purpose:To evaluate the image quality of high-spatialresolution three-dimensional magnetic resonance cholangiography (MRC) with a high-sampling-efficiency technique (sampling perfection with application optimized contrasts using different flip angle evolutions [SPACE]) in comparison with a conventional constant flip angle (FA) sequence at 3T. Materials and Methods:Eighteen volunteers were examined on a 3T MR unit using MRC imaging performed with three different free-breathing three-dimensional T2-weighted turbo spin-echo (TSE) sequences: 1) SPACE (spatial resolution, 1.1 ϫ 1.0 ϫ 0.84 mm), 2) constant FA (1.1 ϫ 1.0 ϫ 0.84 mm), and 3) SPACE at a higher resolution (SPACE HR; 1.0 ϫ 0.9 ϫ 0.644 mm). A five-point scale was used to compare overall image quality and visualization of the third branches of the bile duct (B2, B6, and B8). Depictions of cystic duct insertion and the highest order of bile duct visible were also compared.Results: MRC with SPACE and SPACE HR sequences produced significantly better overall image quality than the constant FA sequence. In all analyses of duct visibility, SPACE and SPACE HR sequences showed higher scores than the constant FA sequence. Conclusion:High-resolution three-dimensional MRC with SPACE at 3T allows high-quality imaging of the biliary tract, and has the ability to depict nondilated intrahepatic bile ducts (IHBD) in healthy volunteers.

Secondary Breast Lymphoma: A Case Report

“…The most common clinical fi nding in B-cell lymphoma of the breast is a painless palpable mass, less frequently associated with retraction of the nipple [2,7,8]. Skin changes or edema, on the other hand, have been reported to occur more often in T-cell breast lymphoma [4,9].…”

“…Skin changes or edema, on the other hand, have been reported to occur more often in T-cell breast lymphoma [4,9]. Similarly, image fi ndings have been described as non-specifi c with a broad variety of features leaving an uncertainty to distinguish between breast carcinoma or hematological malignancy [2,4,7,8,[10][11][12]. Due to its rare occurrence and its non-specifi c fi ndings, these ambiguities can lead to misinterpretations of clinical and radiological features which may result in a delayed or inaccurate diagnosis.…”

Comparison of SPACE and 3D TSE MRCP at 1.5T Focusing on Difference in Echo Spacing

“…6,7 Three-tesla MR imaging has recently been attempted as well using 3D MRCP with SPACE (sampling perfection with application optimized contrasts using diŠerent ‰ip angle evolutions) sequence. 8,9 This reduces speciˆc absorption rate (SAR) for 3.0T imaging by using a variable ‰ip angle and reduces acquisition time when combined with the GRAPPA (generalized autocalibrating partially parallel acquisition) reconstruction algorithm. It also reduces echo spacing, an advantage not previously explored.…”

“…It has been already reported superior to conventional 3D TSE MRCP at 3.0T. 9 At 3.0T, it is necessary to reduce the ‰ip angle or use a variable ‰ip angle to limit the SAR, 9 whereas at 1.5T, the SAR causes less disturbance, thus negating the need to use a variable ‰ip angle. In addition, short echo time (TE), which can be produced by varying ‰ip angle in 3.0T MR imaging, is not an original requirement for MRCP.…”

Clinical application of navigator-gated three-dimensional balanced turbo-field-echo magnetic resonance cholangiopancreatography at 3 T: prospective intraindividual comparison with 1.5 T

“…The development of respiratory-triggered three-dimensional (3D) T2-weighted (T2W) turbo spin echo (TSE) techniques made MRCP highly useful [3] and a new technique, sampling perfection with the application of optimized contrasts using different flip angle evolutions (SPACE) improved the image quality of MRCP scans [4][5][6]. At 1.5 T unit, it is reported that navigator-gated MRCP with a balanced turbo-field-echo (BTFE) sequence is more useful than conventional respiratorytriggered MRCP with a heavily T2W sequence for evaluating the gallbladder and cystic duct in patients scheduled for laparoscopic cholecystectomy because the former reduces motion artifacts due to irregular breathing and clearly shows concentrated or hemorrhagic bile whose detection is difficult on TSE sequences [7,8].…”