AJR
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Abstract Freely available
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Chang, J. S.
Right arrow Articles by Lee, V. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Chang, J. S.
Right arrow Articles by Lee, V. S.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?
Hotlight (NEW!)
Right arrow
What's Hotlight?

Opposed-Phase MRI for Fat Quantification in Fat-Water Phantoms with 1H MR Spectroscopy to Resolve Ambiguity of Fat or Water Dominance

Jerry S. Chang1, Bachir Taouli2, Nouha Salibi3, Elizabeth M. Hecht2, Deanna G. Chin4 and Vivian S. Lee2

1 Westwood Radiology Associates, Pascack Valley Hospital, Westwood, NY 07675.
2 Department of Radiology, NYU Medical Center, 560 First Ave., TCH-HW 202, New York, NY 10016.
3 Siemens Medical Solutions, Malvern, PA 19355.
4 Department of Radiology, Robert Wood Johnson University Hospital, East Brunswick, NJ 08816.


Figure 1
View larger version (8K):

[in a new window]
  		Fig. 1A —In-phase and opposed-phase imaging of fat-water phantoms. Curve of signal intensity (SI) of fat-water phantoms on in-phase (•) and opposed-phase ({blacksquare}) images versus phantom fat fraction (FFP). Arrow points to maximum SI loss on opposed-phased images for fat fraction of 50%.

 

Figure 2
View larger version (32K):

[in a new window]
  		Fig. 1B —In-phase and opposed-phase imaging of fat-water phantoms. Corresponding in-phase and opposed-phase images and 1H MR spectroscopy (MRS) images of three fat-water phantoms placed in water bath; phantoms are composed of 30% (B), 50% (C), or 70% (D) fat. Water peak (short arrow) is 4.7 ppm and fat peak (long arrow) ranges from 1 to 1.5 ppm on MRS images. Example of placement of regions of interest (circles, C) is shown in C. Maximum signal loss on opposed-phase images is seen for phantom with 50% fat (C). Phantoms with 30% (A) and 70% (B) fat are indistinguishable on opposed-phase images. Without MRS to resolve for fat-water dominance, high fat fraction may be misinterpreted as low fat fraction.

 

Figure 3
View larger version (30K):

[in a new window]
  		Fig. 1C —In-phase and opposed-phase imaging of fat-water phantoms. Corresponding in-phase and opposed-phase images and 1H MR spectroscopy (MRS) images of three fat-water phantoms placed in water bath; phantoms are composed of 30% (B), 50% (C), or 70% (D) fat. Water peak (short arrow) is 4.7 ppm and fat peak (long arrow) ranges from 1 to 1.5 ppm on MRS images. Example of placement of regions of interest (circles, C) is shown in C. Maximum signal loss on opposed-phase images is seen for phantom with 50% fat (C). Phantoms with 30% (A) and 70% (B) fat are indistinguishable on opposed-phase images. Without MRS to resolve for fat-water dominance, high fat fraction may be misinterpreted as low fat fraction.

 

Figure 4
View larger version (34K):

[in a new window]
  		Fig. 1D —In-phase and opposed-phase imaging of fat-water phantoms. Corresponding in-phase and opposed-phase images and 1H MR spectroscopy (MRS) images of three fat-water phantoms placed in water bath; phantoms are composed of 30% (B), 50% (C), or 70% (D) fat. Water peak (short arrow) is 4.7 ppm and fat peak (long arrow) ranges from 1 to 1.5 ppm on MRS images. Example of placement of regions of interest (circles, C) is shown in C. Maximum signal loss on opposed-phase images is seen for phantom with 50% fat (C). Phantoms with 30% (A) and 70% (B) fat are indistinguishable on opposed-phase images. Without MRS to resolve for fat-water dominance, high fat fraction may be misinterpreted as low fat fraction.

 

Figure 5
View larger version (4K):

[in a new window]
  		Fig. 2 —Correlation between fat fraction calculated using opposed-phase imaging (FFOPI) with 1H MR spectroscopy for qualitative analysis to resolve ambiguity of fat or water dominance in phantom with known fat fraction (FFP). y = 1.09x - 0.02, R2 = 0.99, p < 0.001.

 

Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati    What's this?



HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2006 by the American Roentgen Ray Society.