Contrast-enhanced ultrasound (CEUS) is a new potential modality for the quantitative
evaluation of the microvascular perfusion of a parenchymal organ.
To prospectively and quantitatively analyse the role of CEUS in evaluating renal perfusion
for assessing renal function in children with ureteropelvic junction obstruction (UPJO).
The study protocol was approved by the local ethics committee, and written informed
consent was obtained from the patients’ parents or guardians. Ultrasonography, CEUS,
and radioisotope renography were performed for 51 children (42 boys, 9 girls; mean
age, 6.75 ± 4.14 years) with unilateral UPJO. The slope of the ascending curve (A),
time to peak (TTP), peak intensity (PI), and area under the curve (AUC) were recorded
during CEUS; quantitative data were calculated by QLab system (semiautomated border
tracking, Philips Healthcare) software. Sensitivity and specificity values were determined
for CEUS with respect to radioisotope renography.
CEUS was used to evaluate 102 kidneys in 51 patients, for which the perfusion time–intensity
curve (TIC) was determined. The TIC of renal cortical perfusion in all groups showed
an asymmetrical single–peak curve, which could be clearly distinguished between the
experimental group and the control group. Compared with the control group, the experimental
group showed a markedly prolonged TTP but a significantly decreased A (P < 0.05).
There was no significant correlation between the AUC, PI and differential renal function
(DRF), but the correlation coefficient between TTP, A and DRF remained significant
(p < 0.001).The receiver operating characteristic (ROC) curves drawn to differentiate
DRF using the TTP value yielded an area under the ROC curve (AUROC) of 0.86. For a
quantitative assessment of DRF less than 40% by CEUS, the sensitivity and specificity
values were 92.86% and 76.14%, respectively.
Unlike in previous studies, no significant difference in the AUC or PI was found between
the control group and the experimental group in this study (P > 0.05). Renal blood
perfusion could not be evaluated overall by CEUS. Parenchymal thinning may be considered
a limitation to CEUS.
Summary TableDiagnostic performance of TTP and A values.