Thick curved planar reformation of unenhanced multislice computed tomography demonstrating urolithiasis.
OBJECTIVE
To determine what slice thickness provides optimal curved planar reformation (CPR) images of the urinary tract.


METHODS
A total of 75 consecutive patients with acute flank pain were included in a retrospective pilot study and underwent unenhanced multislice computed tomography (MSCT) (collimation 3.75 mm, pitch 6, reconstruction increment 3 mm, working voltage 120 kV, and tube current 100 mA) with CPR reconstruction of the urinary tract. CPRs with differing slice thicknesses of 3-20 mm at 1-mm increments to reformat each ureter were assessed in each patient separately. Two radiologists and a urologist evaluated the quality of the reformatted images by judging each ureter in terms of the delineation of all its parts using a 5-point scale (insufficient, poor, moderate, good, and excellent).


RESULTS
Of the 75 patients in our cohort, 52 (69%) had urolithiasis. CPR images could be made of all ureters in all patients. Good to excellent image quality was found in the CPRs performed with a slice thickness of 8-12 mm: 27.7% at 8 mm, 14.3% at 9 mm, 26.9% at 10 mm, 12.6% at 11 mm, and 18.5% at 12 mm. Thus, a slice thickness of 8-12 mm determined a cumulative likelihood of 96.7% to demonstrate the ureter totally.


CONCLUSIONS
The results of our study have shown that CPR is a feasible and quick useful tool. CPRs of the urinary tract with a slice thickness of 8-12 mm are best for good delineation of the whole ureter.
Wehrschuetz
M
M
Department of Radiology, Medical University Graz, Graz, Austria. martin.wehrschuetz@meduni-graz.at
Gallé
G
G
Wehrschuetz
E
E
Sorantin
E
E
Schaffler
G
G
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*; D052878:Urolithiasis / Q000000981:diagnostic imaging*; D055815:Young Adult