Ces radiol. 2019, 73(4):250-255 | DOI: 10.55095/CesRadiol2019/038

Upper urinary tract dimensions on CT urography in adults and how they are affected by the hydration statusOriginal article

Tereza Dvořáková¹, Lenka Bakaj Zbrožková², Filip Čtvrtlík², Kateřina Langová³, Milan Král⁴, Zbyněk Tüdös²

¹ Lékařská fakulta UP, Olomouc

² Radiologická klinika LF UP a FN, Olomouc

³ Ústav lékařské biofyziky LF UP, Olomouc

⁴ Urologická klinika LF UP a FN, Olomouc

Aim: Dilatation of the urinary tract is an important sign in the diagnosis of its obstruction. Unfortunately, there is a significant inter-individual variability in the size of the renal pelvis and ureter, furthermore, their size is influenced by other factors, e.g. hydration status. The aim of the work was to evaluate the effect of hydration on urinary tract diameters.

Methods: Totally 110 patients (77 men, 33 women, average age 65 years) with bilateral normal finding on the both kidneys met the inclusion criteria. The CT protocol included an unenhanced, corticomedular, nephrographic, and excretory phase. During the examination, 70 ml of contrast agent and 30 ml of saline were injected, followed by an intravenous infusion of 120 ml saline to promote diuresis. We measured the intra-renal and extra-renal anteroposterior diameter (APD) of the pelvis and the width of the abdominal ureter in an unenhanced phase (low hydration status) and in an excretory phase (high hydration status). We statistically compared the dimensions in the unenhanced and excretory phases and then we compared the values between the right and left side.

Results: The difference in intra- and extra-renal APD and abdominal ureter width in unenhanced and excretory phases was statistically significant on both sides: intra-renal APD on the right - median 5.55 mm (range 2-15.5 mm) vs. median 7.5 mm (range 2.7-17.2 mm); extra-renal APD on the right - median 7 mm (range 2-24.4 mm) vs. 9.15 mm (range 1.8-25.3 mm); intra-renal APD on the left - median 5.45 mm (range 1.6-16.7 mm) vs. median 6.6 mm (range 1.8-25.3 mm); extra-renal APD on the left - median 7.15 mm (range 1.7-18.6 mm) vs. median 8.55 mm (range 1.8-25.8 mm); the width of ureter on the right - median 3.83 mm (range 1.8-9.4 mm) vs. median 4.25 mm (range 2.05-9.25 mm); the width of ureter on the left - median 3.9 mm (range 1.55-7.9 mm) vs. 4.23 mm (range 1.55-9.65 mm), all comparisons on the significance level p < 0.001. Comparison of diameters between the left and right side revealed mean differences less than 0.8 mm in renal pelvis dimensions and less than 0.3 mm in ureters.

Conclusion: The diameters of the adult renal pelvis and ureter revealed great inter-individual variability and significant influence of hydration status. Lateral symmetry seems to be more reliable tool for the diagnosis of urinary tract obstruction, than urinary tract dimensions measurement.

Keywords: organism hydration status, multi-detector computed tomography, renal pelvis, upper urinary tract, ureter, urography

Grants and funding:

Práce byla podpořena vnitřním grantem Univerzity Palackého: IGA_LF_2019_002.

Accepted: November 15, 2019; Published: December 1, 2019  Show citation