Field strength and diffusion encoding technique affect the apparent diffusion coefficient measurements in diffusion-weighted imaging of the abdomen.

Published

Journal Article

OBJECTIVES: The purpose of this study is to determine what effects a variety of diffusion encoding techniques at 1.5 T and 3 T have on measured abdominal apparent diffusion coefficient (ADC) values obtained in a healthy population. MATERIALS AND METHODS: Sixteen healthy male volunteers were enrolled in this prospective Institutional Review Board-approved study following written informed consent. Imaging was performed on a 1.5 T and a 3 T magnetic resonance system (Siemens, Erlangen) with several abdominal axial diffusion weighted imaging (DWI) acquisitions: an orthogonal diffusion encoding with b-values of 0/400 seconds/mm, and a series of four 3-scan trace weighted acquisitions with b-values of 0/50, 0/400, 0/800, 0/50/400/800 seconds/mm, respectively. The mean ADC values were calculated for 3 regions of interest (ROI) in 5 locations (right hepatic lobe, spleen, pancreatic head, body, and tail). The ADC data were analyzed using a repeated-measures analysis of variance. RESULTS: There was a significant difference between measured ADC values at 1.5 T and 3 T for liver (P < 0.001), but not for pancreas (P = 0.427) or spleen (P = 0.167). There was no significant difference (P > 0.999) in the measured ADC values between the orthogonal encodings and the 3-scan trace weighted encoding with the same b-value. There were significant differences (P < 0.001) between all 4 weighting schemes for the 3-scan trace with the measured ADC decreasing with increasing b-value. CONCLUSION: Measured abdominal ADC values depend on the exact selection of b-value used for encoding for liver, pancreas, and spleen. In addition, the measured ADC values depend on the field strength of the scanner for liver.

Full Text

Duke Authors

Cited Authors

  • Dale, BM; Braithwaite, AC; Boll, DT; Merkle, EM

Published Date

  • February 2010

Published In

Volume / Issue

  • 45 / 2

Start / End Page

  • 104 - 108

PubMed ID

  • 20027117

Pubmed Central ID

  • 20027117

Electronic International Standard Serial Number (EISSN)

  • 1536-0210

Digital Object Identifier (DOI)

  • 10.1097/RLI.0b013e3181c8ceac

Language

  • eng

Conference Location

  • United States