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Retroperitoneoscopic One-Trocar-Assisted Pyeloplasty in Children: An Age-Related Evaluation.

INTRODUCTION
The aim of this study was to evaluate the efficacy of the retroperitoneoscopic one -trocar -assisted pyeloplasty (OTAP) in children of different ages.


MATERIALS AND METHODS
Clinical data of all children who underwent OTAP for ureteropelvic junction (UPJ) obstruction at our Institution, between 2006 and 2014, were reviewed by focusing on demographics, surgical management, and outcomes. Data were analyzed by dividing patients into three groups according to age at operation: patients younger than 2 years (group 1), between 2 and 6 years (group 2), and older than 6 years (group 3).


RESULTS
During the study period, 70 children (50 males) underwent OTAP (45 left and 25 right). A 10-mm ballooned trocar was inserted under the 11-12th rib and pneumoretroperitoneum was induced (12 mmHg pressure). Through an operative scope, the UPJ was carefully mobilized and exteriorized to the skin level to perform conventional Anderson-Hynes dismembered pyeloplasty. Mean age was 48 months (range, 1 month-14 years). Thirty-six patients (mean age 8.8 months) were in G1, 18 patients (mean age 4.2 years) in G2, and 16 patients (mean age 10.2 years) in G3. There were no intraoperative complications. Mean operative time was 137 minutes: 128 minutes (range, 85-213) in G1, 118 minutes (range, 90-215) in G2 (P > .05 versus G1), and 154 minutes (range, 95-215) in G3 (P < .05 versus G1; P < .05 versus G2). Conversion (an extension of the subcostal incision) rate was 27.1%: 16.6% in G1, 22.2% in G2 (P > .05 versus G1), and 56.25% in G3 (P < .05 versus G1; P < .05 versus G2). At a mean follow-up of 29 months (range, 12 months-5 years), recurrence was observed in 3 patients (2 G1, 1 G3).


CONCLUSIONS
Our results show that OTAP is a good alternative in children younger than 6 years. OTAP is more challenging in older children because of the thickness of the abdominal wall and the higher incidence of aberrant crossing vessels.