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 Georgiades, C. S.
Right arrow Articles by Smith, D. P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Georgiades, C. S.
Right arrow Articles by Smith, D. P.
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?

Differences of Renal Parenchymal Attenuation for Acutely Obstructed and Unobstructed Kidneys on Unenhanced Helical CT

A Useful Secondary Sign?

Christos S. Georgiades1, Carolyn J. Moore2 and David P. Smith3

1 Department of Radiology, Johns Hopkins Hospital, 600 N. Wolfe St., Baltimore, MD 21287, and Johns Hopkins University School of Medicine, Baltimore, MD 21287.
2 Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21287.
3 Department of Radiology, Johns Hopkins Bayview Hospital, Baltimore, MD 21224.



View larger version (58K):

[in a new window]
  		Fig. 1. —Axial unenhanced CT scan of 24-year-old man with acute-onset pain in right flank radiating to left lower abdomen and microhematuria. Image obtained at level of kidneys shows renal parenchyma on right (27 H) to be less dense than parenchyma on left (35 H). Obstructing 4-mm ureterovesicular junction calculus (not shown) was seen. Image of same patient is shown in Figure 6.

 


View larger version (29K):

[in a new window]
  		Fig. 2. —Bar graph shows attenuation of renal parenchyma for obstructed and unobstructed kidneys. Third column shows average attenuation of healthy kidneys. Note significant difference between attenuation of obstructed kidney and that of unobstructed and healthy kidneys. The latter two show no significant difference. Error bars indicate standard deviations.

 


View larger version (27K):

[in a new window]
  		Fig. 3. —Graph shows number of radiologists (maximum of 10) who visually detected lower attenuation in obstructed kidney versus actual percentage of difference in attenuation between acutely obstructed renal parenchyma and unobstructed side in three patients, A, B, and C. When difference in attenuation is great enough for most or all radiologists to detect visually, actual difference is more than two standard deviations (SD) above normal and, thus, a statistically significant finding; 1 SD and 2 SD indicate above-average attenuation difference between normal kidneys.

 


View larger version (102K):

[in a new window]
  		Fig. 4. —Axial unenhanced helical CT scan obtained at level of kidneys in 55-year-old woman with right flank pain radiating to groin and microhematuria. Attenuation of right kidney is 36 H, and attenuation of left kidney is 38 H. One-millimeter calculus (not shown) was seen at right ureterovesicular junction. Patient is represented by "A" in Figure 3.

 


View larger version (100K):

[in a new window]
  		Fig. 5. —Axial unenhanced helical CT scan obtained at level of kidneys in 44-year-old man with right flank pain and microhematuria. Attenuation of right kidney is 30 H and that of left kidney is 35 H. Two-millimeter calculus (not shown) was seen at right ureterovesicular junction. Patient is represented by "B" in Figure 3.

 


View larger version (84K):

[in a new window]
  		Fig. 6. —Axial unenhanced helical CT scan obtained at level of kidneys in 24-year-old man with acute-onset pain in right flank radiating to right lower abdomen and microhematuria. Attenuation of right kidney is 27 H and that of left kidney is 35 H. Four-millimeter calculus (not shown) was seen at right ureterovesicular junction. Patient is represented by "C" in Figure 3.

 


View larger version (26K):

[in a new window]
  		Fig. 7. —Graph illustrates relationship between degree of ureteral dilatation (dashed line and {blacktriangleup}) and percentage of attenuation difference between two kidneys (solid line and x). Correlation factor for these two secondary signs is 0.61; x-axis shows amount of attentuation in 26 patients with acute ureteral obstruction charted by increasing attenuation difference.

 


View larger version (28K):

[in a new window]
  		Fig. 8. —Graph illustrates relationship between degree of perinephric stranding (dashed line and {blacktriangleup}) and percentage of attenuation difference between two kidneys (solid line and x). Correlation factor for these two secondary signs is 0.34; x-axis shows amount of attentuation in 26 patients with acute ureteral obstruction charted by increasing attenuation difference.

 

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 © 2001 by the American Roentgen Ray Society.