Thin-section diffusion-weighted magnetic resonance imaging of the brain with parallel imaging


Oner A., Celik H., TALI E. T., Akpek S., TOKGÖZ N.

Acta Radiologica, vol.48, no.4, pp.456-463, 2007 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 48 Issue: 4
  • Publication Date: 2007
  • Doi Number: 10.1080/02841850701297506
  • Journal Name: Acta Radiologica
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.456-463
  • Keywords: brain, DWI, parallel imaging, thin section
  • Lokman Hekim University Affiliated: No

Abstract

Background: Thin-section diffusion-weighted imaging (DWI) is known to improve lesion detectability, with long imaging time as a drawback. Parallel imaging (PI) is a technique that takes advantage of spatial sensitivity information inherent in an array of multiple-receiver surface coils to partially replace time-consuming spatial encoding and reduce imaging time. Purpose: To prospectively evaluate a 3-mm-thin-section DWI technique combined with PI by means of qualitative and quantitative measurements. Material and Methods: 30 patients underwent conventional echo-planar (EPI) DWI (5-mm section thickness, 1-mm intersection gap) without parallel imaging, and thin-section EPI-DWI with PI (3-mm section thickness, 0-mm intersection gap) for a b value of 1000 s/mm2, with an imaging time of 40 and 80 s, respectively. Signal-to-noise ratio (SNR), relative signal intensity (rSI), and apparent diffusion coefficient (ADC) values were measured over a lesion-free cerebral region on both series by two radiologists. A quality score was assigned for each set of images to assess the image quality. When a brain lesion was present, contrast-to-noise ratio (CNR) and corresponding ADC were also measured. Student t-tests were used for statistical analysis. Results: Mean SNR values of the normal brain were 33.614.35 and 32.987.19 for conventional and thin-slice DWI (P0.05), respectively. Relative signal intensities were significantly higher on thin-section DWI (P0.05). Mean ADCs of the brain obtained by both techniques were comparable (P0.05). Quality scores and overall lesion CNR were found to be higher in thin-section DWI with parallel imaging. Conclusion: A thin-section technique combined with PI improves rSI, CNR, and image quality without compromising SNR and ADC measurements in an acceptable imaging time. © 2007 Taylor and Francis.