Comparison of prone vs. supine unenhanced CT imaging in patients with clinically suspected ureterolithiasis.
To retrospectively evaluate whether prone CT scanning is superior to supine scanning for correct localization of distal urinary calculi in patients with acute flank pain.



Consecutively performed unenhanced CT scans in patients with acute flank pain were retrospectively analyzed in 150 patients in supine and another 150 patients in prone position. Images were reviewed by two radiologists on consensus. Findings in both groups were compared using two-sided Fisher Exact tests and Wilcoxon-Mann-Whitney test.



Urinary calculi were found in 67% of patients in each group. In the supine scanning group, there were 16 cases, in which the location of the stone was equivocal being either located intramurally at the ureterovesical junction (UVJ) or having already passed into the bladder. In contrast, in the prone imaging group all distal stones could be allocated accurately, either to the intramural UVJ or the urinary bladder (37 intramural UVJ stones and six bladder stones in prone scanning group vs. 21 intramural UVJ stones and one bladder stone when scanned supine).



Prone scanning is superior to supine CT scanning for acute flank pain to accurately distinguish intramural UVJ stones from stones that have already passed into the bladder, a distinction which influences patient management.
Department of Radiology, Landeskrankenhaus Salzburg, Paracelsus Medical University, Müllner-Hauptstrasse 48, 5020, Salzburg, Austria. m.meissnitzer@salk.at.
Matthias
M
Meissnitzer
Department of Radiology, Landeskrankenhaus Salzburg, Paracelsus Medical University, Müllner-Hauptstrasse 48, 5020, Salzburg, Austria.
Thomas
T
Meissnitzer
Department of Urology, Landeskrankenhaus Salzburg, Paracelsus Medical University, Müllner-Hauptstrasse 48, 5020, Salzburg, Austria.
Stephan
S
Hruby
Department of Radiology, Landeskrankenhaus Salzburg, Paracelsus Medical University, Müllner-Hauptstrasse 48, 5020, Salzburg, Austria.
Stefan
S
Hecht
Department of Radiology, Landeskrankenhaus Salzburg, Paracelsus Medical University, Müllner-Hauptstrasse 48, 5020, Salzburg, Austria.
Andreas
A
Gutzeit
Department of Radiology, Landeskrankenhaus Salzburg, Paracelsus Medical University, Müllner-Hauptstrasse 48, 5020, Salzburg, Austria.
Laura
L
Holzer-Frühwald
Department of Radiology, Landeskrankenhaus Salzburg, Paracelsus Medical University, Müllner-Hauptstrasse 48, 5020, Salzburg, Austria.
Klaus
K
Hergan
Department of Radiology, Landeskrankenhaus Salzburg, Paracelsus Medical University, Müllner-Hauptstrasse 48, 5020, Salzburg, Austria.
Rosemarie
R
Forstner
D000208:Acute Disease; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016684:Prone Position; D012189:Retrospective Studies; D016683:Supine Position; D014057:Tomography, X-Ray Computed / Q000379:methods*; D053039:Ureterolithiasis / Q000000981:diagnostic imaging*
Computed tomography; Prone position; Supine position; Ureteral calculi; Urolithiasis
Australas Radiol. 2001 Aug;45(3):291-7
11531751
Urology. 2007 Jan;69(1):27-31; discussion 31-3
17270606
Curr Urol Rep. 2016 Mar;17(3):24
26874536
Urologe A. 2000 Mar;39(2):166-70
10768228
J Chin Med Assoc. 2008 Jan;71(1):30-6
18218557
AJR Am J Roentgenol. 2008 Aug;191(2):396-401
18647908
Eur Urol. 2016 Mar;69(3):468-74
26318710
J Urol. 1999 Sep;162(3 Pt 1):688-90; discussion 690-1
10458343
Lancet. 1998 Jun 13;351(9118):1797-801
9635968
J Urol. 1998 Mar;159(3):735-40
9474137
Radiology. 2003 Aug;228(2):319-29
12819343
Br J Radiol. 2012 Aug;85(1016):1118-22
22496069
BJU Int. 2015 Jun;115(6):946-50
24925167
Urology. 2008 Sep;72(3):504-7
18653216
AJR Am J Roentgenol. 1999 Apr;172(4):977-81
10587131
Int J Clin Pract. 2014 Feb;68(2):216-21
24372674
Cochrane Database Syst Rev. 2012 May 16;(5):CD006029
22592707