Morphofunctional outcomes of laparoscopic pyeloplasty in infants of the first three months of life

Introduction. This study describes authors’ experience in performing laparoscopic pyeloplasty in infants whose age does not exceed 3 months of life, and compares pre- and postoperative results of these surgeries in order to answer the question - does the laparoscopic technology for the treatment of hydronephrosis in newborns and infants provide acceptable results based on improving kidney morphology and function? Material and methods. 105 children, aged 3 months, were enrolled into this retrospective study who for 8 years, since 2012, have been laparoscopically operated on for congenital hydronephrosis. Because of bilateral renal damage, a total of 110 surgeries were performed, including simultaneous pyeloplasty in 5 patients. All patients had dismembered pyeloplasty with the Anderson-Hynes technique via transparietal laparoscopic access. Indications for surgery were: decreased renal function with obstruction signs of urine outflow from the pelvis confirmed by radioisotope renography; a combination of reduction of parenchyma thickness and increase of pelvis diameter at serial ultrasound studies; or a combination of these pathologies with urinary tract infection. During the trial, the following parameters were recorded: demographic data, findings of perioperative diagnostic examinations, surgical details, recovery process after surgery and long-term consequences. Results. The average age of patients was 50.24 days. Of 105 patients, 60 (57.14%) were less than 1 month old, and the remaining 45 (42.86%) were 1-3 months old. Gender distribution in groups was as follows: m / f = 73:32. Unilateral operations on the left kidney were in 61.82% patients, on the right kidney - in 33.64% patients. 4.54% patients had bilateral pyeloplasty. Average duration of surgery was 73.07 minutes (40-120 minutes). The average length of hospital stay was 4.19 days (2-9 days). At the early postoperative period, 4 (3.6%) patients developed postoperative complications - urinoma formation. A comparison of pre- and postoperative renal morphometry findings by ultrasound and Doppler ultrasound examination showed a significant decrease of renal pelvis dimensions and improved renal blood flow. The pelvis size decreased in average from 23.5 to 5.5 mm (p = 0.001), and RI from 0.72 to 0.64 (p = 0.001). Functioning of the operated kidney, as showed by the radioisotope renography, improved from 34 to 45.27 (p = 0.001). Long-term follow-up observation revealed one relapse of the disease (0.9%) - stenosis of pyeloureteral anastomosis which required a repeated laparoscopic pyeloplasty. One patient (0.9%)/ who was under follow-up observation for 36 months, had deterioration and loss of kidney function without signs of renal obstruction at the level of pyeloureteral segment which required laparoscopic nephrectomy. Thus, taking into account one relapse and loss of kidney function in one patient, we can state that the effectiveness of laparoscopic pyeloplasty in our study was 98.2%. Conclusion. Summarizing results of the applied laparoscopic pyeloplasty in the youngest group of patients whose age does not exceed 3 months of life, it can be stated that the minimally invasive approach contributes to normalizing morphological and functional parameters of kidney.

Quantitative Assessment of Renal Function In Children with UPJO By Contrast-enhanced Ultrasound ： A Pilot Study

Background: Contrast-enhanced ultrasonography (CEUS) is a new potential modality for the quantitative evaluation of the microvascular perfusion of renal parenchyma.Objective: To prospectively evaluate the diagnostic value of CEUS in assessing renal function in patients with ureteropelvic junction obstruction (UPJO).Methods: The study protocol was approved by the ethics committee of Beijing Children’s Hospital (Beijing,China), and written informed consent was obtained from the patients’ parents or guardians. Ultrasonography (US), CEUS, and radioisotope renography were performed in 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; the quantitative data were calculated by the QLAB system (semiautomated border tracking, Philips Healthcare) software. Sensitivity and specificity values were determined for CEUS and compared with radioisotope renography.Results: A total of 102 kidneys in 51 patients were depicted by CEUS and the perfusion time-intensity curve (TIC).CEUS depicted 102 kidneys in 51 patients, in whom 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 to the control group, the TTP was markedly prolonged but A was significantly decreased in the experimental group (P < 0.05). There was no significant correlation between AUC, PI and DFR，but the correlation coefficient between TTP, A and DFR remained significant (p<0.001).The receiver operating characteristic （ROC）curve drawn to differentiate the differential renal function (DRF) using the TTP value provided an area under the ROC curve (AUROC) of 0.86. The diagnostic performance of contrast-enhanced US was better than that of US, as the sensitivity and specificity values were 92.86% and 76.14%, respectively.Conclusions: This preliminary experience represents the first report of evaluating the diagnostic value of CEUS in assessing renal function in children with UPJO. CEUS is a highly sensitive, rapid, and diagnostic imaging modality for detecting and monitoring renal function noninvasively.

The connection of hydronephrosis and microcirculation deterioration

In this study, we have analyzed the influence of hydronephrosis upon the microcirculation system, in situations of pyeloureteral junction obstruction. Herein, bulbar conjunctiva has been chosen as the object of this biomicroscopic study because of its simplicity and the method availability in clinic practice. In fulfilling this work, we ascertained the connections between extravascular, intravascular, vascular and general conjunctival indices of the patients before radical and paliatic correction of the pyeloureteral junction obstruction (i.e. by open and laparoscopic pyeloplasty, endopyelotomy, laser resection and balloon dilatation). We concluded that, apart from the proved deterioration of kidney function, systemic deteriorations of microcirculation may be observed in situations of clinically marked hydronephrosis, according to the results of radioisotope renography and excretory urography.