#PINEAPPLE JUICE MRI CONTRAST FREE#
The IDEAL technique is compatible with many pulse sequences, including gradient-echo, TSE, or balanced steady-state free precession. The most commonly used three-point Dixon technique is iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL), which maps field inhomogeneities and uses asymmetric sampling (unevenly spaced echoes) for maximum signal-to-noise ratio (SNR). Three-point Dixon techniques correct for T2* decay by using the data from a third echo.
The signal in two-point Dixon images is adversely affected by magnetic field (B0) and radiofrequency (B1) inhomogeneity, either intrinsic to the system or due to the presence of tissue iron. 3A, 3B, 3C, 3D ), which acquire thinner, contiguous slices within a breath-hold, are preferable to 2D gradient-echo sequences. Fat content may be estimated by assessing the signal drop-off on opposed-phase images 3D two-point Dixon techniques (Fig. This sequence yields images in which water and fat protons have the same or opposing phases (Fig. Traditionally, 2D gradient-echo sequences with two TEs have been used. Thus, accurate assessment of pancreatic fat content may be useful. However, studies in animals and humans have shown that fatty pancreas is associated with increased severity of acute pancreatitis or higher incidence of postoperative complications. Estimation of pancreatic fat is currently not considered part of routine MRI assessment. T1-weighted sequences are useful for assessing hemorrhage, such as within inflammatory collections in acute pancreatitis (Fig. In this article, we discuss the sequences that form state-of-the-art MRI examination of the pancreas. In our practice, it is used as the primary investigation for suspected biliopancreatic pain, staging chronic pancreatitis, and diagnosis and follow-up of cystic pancreatic tumors. MRI is used as a problem-solving tool in patients with elevated liver function tests, acute pancreatitis, and pancreatic cancer. We have noted that, with improved image quality and diagnostic accuracy, the volume of pancreatic MRI cases has substantially increased over the past few years.
These improvements result in fast sequences with excellent diagnostic quality. Secretin-enhanced MR cholangiopancreatography (S-MRCP) protocols have been developed for a more complete assessment of pancreatic ducts and glandular function. Several new sequences have been introduced for performing pancreatic MRI, and 3D T1-weighted and MRCP sequences are routinely used. Higher field strength (3 T) scanners are increasingly used. Shorter scanners with wider bores allow scanning of obese and claustrophobic patients. Current MRI scanners have more than 100 integrated coil elements and more than 30 independent radiofrequency channels. In the past few years, MRI scanners have become more sophisticated.
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