The predictive value of the first postnatal ultrasound in children with antenatal hydronephrosis.

OBJECTIVE: To evaluate the effectiveness of the first postnatal ultrasound (US) in predicting the final postnatal diagnosis using a database of children followed prospectively for antenatal hydronephrosis, and to compare these findings with a systematic review of the literature. METHODS: The study involved 1441 children who had their radiological evaluation between 3 and 60 days of life, including an US, performed at our institution in 1998-2006. Univariate and multivariate analyses were performed. A systematic review of articles on prenatal hydronephrosis resulted in 31 studies with 2202 patients who met the inclusion criteria for analysis. RESULTS: 62.0% of renal units (RUs) had transient or non-obstructive hydronephrosis. Increasing degree of hydronephrosis correlated with increased risk of urological pathologies (from 29.6% RUs in the mild group to 96.3% RUs in the severe group). A systematic review of the literature indicated very poor quality data, but the findings appeared to be concordant with those from our patient population. CONCLUSION: The findings from this study will help to quantify the incidence of postnatal pathology based upon the first postnatal US parameters. This information is useful for counseling and for determining which postnatal radiological tests will be necessary.

Safety profile of trocar and insufflation needle access systems in laparoscopic surgery.

BACKGROUND: The most common laparoscopic complications are associated with trocar insertion. The purpose of this study was to develop an objective method of evaluating the safety profile of various access devices used in laparoscopic surgery. STUDY DESIGN: In 20 swine, 6 bladed and 2 needle access devices were evaluated. A force profile was determined by measuring the force required to drive the trocar or needle through the fascia and into the peritoneum, at 0 and 10 mmHg. The amount of tissue deformation, the length of blade exposed, and the duration of exposure were measured using a high-speed digital imaging system. RESULTS: The needle system without the sheath required the least driving force and had the most favorable force profile. In contrast, the bladed, nonretractable trocar system required a higher driving force and a rapid loss of resistance. Insertion under a pneumoperitoneum did not significantly alter the force profile of the various access devices except for the amount of tissue deformation. With the bladed system, the blade itself was exposed for an average of 0.5 to 1.0 seconds for a distance of 4.5 to 5.0 cm. In comparison, the needle system was exposed for 0.2 seconds for a distance of 1.8 cm. CONCLUSIONS: We developed a reproducible method of measuring the forces required to place the access systems, their pattern of resistance loss, and the characteristics of the blade exposure. These parameters may provide an adjunctive and objective measurement of safety, allowing for more direct comparison between various trocar designs.

Comparing the quality of the suture anastomosis and the learning curves associated with performing open, freehand, and robotic-assisted laparoscopic pyeloplasty in a swine animal model.

BACKGROUND: It is believed that robotic assistance allows for improved suture reapproximation of tissue and decreases the lengthy learning time that is needed to master laparoscopic suturing. But there have been no studies directly comparing the efficiency of robotic-assisted laparoscopic surgery (RALS) to freehand laparoscopy (LS) and open surgery (OS). The purpose of this study was to compare the quality of the suture anastomosis of the ureteropelvic junction (UPJ) using the three techniques and to evaluate their associated learning curves. STUDY DESIGN: The operative time for dismembered pyeloplasties performed in 57 pigs by 3 inexperienced and 1 experienced surgeon using each of the techniques was measured. The anastomosis was evaluated for water tightness and patency using antegrade and retrograde urodynamic measurements immediately after surgery and 2 weeks postoperatively. The histology of the operated UPJ was also evaluated at 15 days postoperatively. RESULTS: RALS had a shorter procedural time and less steep learning curve compared with LS. Urodynamic measurements for patency and water tightness of the UPJ were comparable to those in the OS group. But with experience, both the RALS and LS procedural times and the urodynamic measurements for water tightness and patency of the UPJ approached those of the OS group. Histologic evaluation demonstrated that there was less collagen III deposition around the operated UPJ in pigs that underwent RALS compared with LS and OS. CONCLUSIONS: Among inexperienced surgeons, the efficiency of performing suturing using RALS is operator independent, requires less time to learn, and is better than those done by LS technique.

In utero treatment for bladder outlet obstruction using robot assisted laparoscopic techniques.

PURPOSE: Bladder outlet obstruction can have devastating consequences. Given the poor outcome, intervention in utero has been advocated in an attempt to salvage pulmonary and renal function. We evaluated whether laparoscopic decompression of the obstructed bladder could be performed efficiently by adapting current robot assisted laparoscopic techniques to access the fetus in utero. MATERIALS AND METHODS: At 95 days of gestation 20 fetal sheep underwent ligation of the urethra and urachus. Two to 5 days later robot assisted laparoscopic vesicostomy was performed. Ultrasound of the kidneys and bladder was performed before each procedure. At 135 days of gestation the urinary tract was evaluated to assess the adequacy of bladder decompression and a patent vesicostomy. RESULTS: After 48 hours of undergoing ligation all fetuses had bilateral moderate hydronephrosis and a markedly distended bladder. In the first 10 fetuses vesicostomy could not be completed laparoscopically due to limited visualization. Additional modifications in trocar placement and gas infusion allowed vesicostomy to be completed laparoscopically in the last 8 fetuses in 2.5 to 4 hours. Urinary tract decompression and a patent vesicostomy were observed in all of these fetuses postoperatively. CONCLUSIONS: We developed specific modifications in current robot assisted laparoscopic techniques and instrumentation to allow the treatment of bladder outlet obstruction in utero. This procedure may be performed efficiently and it may provide advantages over conventional surgery for fetal intervention.