Diffusion weighted imaging in the liver

Abstract

Diffusion weighted magnetic resonance imaging (DWI) is an imaging technique which provides tissue contrast by the measurement of diffusion properties of water molecules within tissues. Diffusion is expressed in an apparent diffusion coefficient (ADC), which reflects the diffusion properties unique to each type of tissue. DWI has been originally used in neuroradiology. More recently, DWI has increasingly been used in addition to conventional unenhanced and enhanced magnetic resonance imaging (MRI) in other parts of the body. The reason for this delay was a number of technical problems inherent to the technique, making DWI very sensitive to artifacts, which had to be overcome. With assessment of ADC values, DWI proved to be helpful in characterization of focal liver lesions. However, DWI should always be used in conjunction to conventional MRI since there is considerable overlap between ADC values of benign and malignant lesions. DWI is useful in the detection of hepatocellular carcinoma in the cirrhotic liver and detection of liver metastases in oncological patients. In addition, DWI is a promising tool in the prediction of tumor responsiveness to chemotherapy and the follow-up of oncological patients after treatment, as DWI may be capable of detecting recurrent disease earlier than conventional imaging. This review focuses on the most common applications of DWI in the liver.

Diffusion-Weighted MR Imaging of the Benign Hepatic Focal Lesions

“…Mean ADC values of cyst and haemangioma were significantly higher than other benign hepatic focal lesions. This coincides with other studies [18] [20] [24].…”

“…So, they exhibit low ADC value in relation to other benign hepatic focal lesions. Our results are coincide with previous studies [18] [29]. But, variability in ADC values is probably due to tumor type, imaging parameters, b value combination, and region of interest placement (whether or not the solid part was included).…”

“…Our results are in agreement with Miller et al, (2010) [12]. The difference between our results and other studies [18] [19] may be attributing to stage of abscess, type of abscess or under therapy.…”

Technical advancements and protocol optimization of diffusion-weighted imaging (DWI) in liver

“…Because of technical challenges, hepatic DWI started around 2005, much later than its application in the brain. DWI for liver imaging was reviewed separately by Taouli et al and Kele et al in 2010 [43,44]. This article will focus on the technical developments and the new applications since then.…”

Abdominopelvic Pain: A Prospective Study of 137 Patients

“…It is inversely related to cellularity, cell membrane integrity, and lipophilicity. Tumors, abscesses, fibrosis, and cytotoxic edema lead to restricted diffusion [7][8][9] .…”