Lins Carolina Freitas, Salmon Carlos Ernesto Garrido, Nogueira-Barbosa Marcello Henrique
Escola Bahiana de Medicina e Saúde Pública, Salvador, BA, Brazil.
Delfin Inteligência Diagnóstica, Salvador, BA, Brazil.
Radiol Bras. 2021 Jan-Feb;54(1):33-42. doi: 10.1590/0100-3984.2019.0086.
The acquisition of images with suppression of the fat signal is very useful in clinical practice and can be achieved in a variety of sequences. The Dixon technique, unlike other fat suppression techniques, allows the signal of fat to be suppressed in the postprocessing rather than during acquisition, as well as allowing the visualization of maps showing the distribution of water and fat. This review of the Dixon technique aims to illustrate the basic physical principles, to compare the technique with other magnetic resonance imaging sequences for fat suppression or fat quantification, and to describe its applications in the study of diseases of the musculoskeletal system. Many variants of the Dixon technique have been developed, providing more consistent separation of the fat and water signals, as well as allowing correction for many confounding factors. It allows homogeneous fat suppression, being able to be acquired in combination with several other sequences, as well as with different weightings. The technique also makes it possible to obtain images with and without fat suppression from a single acquisition. In addition, the Dixon technique can be used as a quantitative method, allowing the proportion of tissue fat to be determined, and, in more updated versions, can quantify tissue iron.
在临床实践中,获取抑制脂肪信号的图像非常有用,并且可以通过多种序列来实现。与其他脂肪抑制技术不同,狄克逊技术允许在图像后处理而非采集过程中抑制脂肪信号,同时还能生成显示水和脂肪分布的图谱。本文对狄克逊技术进行综述,旨在阐述其基本物理原理,将该技术与其他用于脂肪抑制或脂肪定量的磁共振成像序列进行比较,并描述其在肌肉骨骼系统疾病研究中的应用。狄克逊技术已衍生出多种变体,能更一致地分离脂肪和水信号,还能校正多种混杂因素。它可实现均匀的脂肪抑制,能与其他多个序列以及不同加权方式相结合进行采集。该技术还能从单次采集中获取有脂肪抑制和无脂肪抑制的图像。此外,狄克逊技术可用作定量方法,确定组织脂肪比例,并且在更新版本中还能对组织铁进行定量。