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European Radiology

, Volume 20, Issue 5, pp 1047–1051 | Cite as

Coronal reconstruction of unenhanced abdominal CT for correct ureteral stone size classification

  • Nadav Berkovitz
  • Natalia Simanovsky
  • Ran Katz
  • Shaden Salama
  • Nurith Hiller
Gastrointestinal

Abstract

Purpose

To determine whether size measurement of a urinary calculus in coronal reconstruction of computed tomography (CT) differs from stone size measured in the axial plane, and whether the difference alters clinical decision making.

Methods

We retrospectively reviewed unenhanced CT examinations of 150 patients admitted to the emergency room (ER) with acute renal colic. Maximal ureteral calculus size was measured on axial slices and coronal reconstructions. Clinical significance was defined as an upgrading or downgrading of stone size according to accepted thresholds of treatment: ≤5 mm, 6–9 mm and ≥10 mm.

Results

There were 151 stones in 150 patients (male:female 115:34, mean age 41 years). Transverse stone diameters ranged from 1 to 11 mm (mean 4 mm). On coronal images, 56 (37%) stones were upgraded in severity; 46 (30%) from below 5 mm to 6 mm or more, and ten (7%) from 6–9 mm to 10 mm or more. Transverse measurement on the axial slices enabled correct categorization of 95 stones (63%).

Conclusion

Transverse calculus measurement on axial slices often underestimates stone size and provides incorrect clinical classification of the true maximal stone diameter. Coronal reconstruction provides additional information in patients with renal colic that may alter treatment strategy.

Keywords

Computed tomography Calculi Ureter Urinary tract Renal colic 

Notes

Acknowledgements

The authors wish to thank Dr. Jacob Sosna for his critical review and insightful comments on the manuscript, and Mrs Shifra Fraifeld, Research Associate in the Department of Radiology, for her editorial assistance in its preparation.

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Copyright information

© European Society of Radiology 2009

Authors and Affiliations

  • Nadav Berkovitz
    • 1
  • Natalia Simanovsky
    • 1
  • Ran Katz
    • 2
  • Shaden Salama
    • 3
  • Nurith Hiller
    • 1
  1. 1.Department of RadiologyHadassah Mount Scopus - Hebrew University Medical CenterJerusalemIsrael
  2. 2.Department of UrologyHadassah Mount Scopus - Hebrew University Medical CenterJerusalemIsrael
  3. 3.Department of Emergency MedicineHadassah Mount Scopus - Hebrew University Medical CenterJerusalemIsrael

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