Division of Pediatric Surgery, Genitourinary Division University of Campinas - UNICAMP, Campinas, SP, Brazil.
Int Braz J Urol. 2012 Jul-Aug;38(4):448-55. doi: 10.1590/s1677-55382012000400003.
Dilation of urinary tract occurs without the presence of obstruction. Diagnostic methods that depend on renal function may elicit mistaken diagnosis. Whitaker (1973) proposed the evaluation of urinary tract pressure submitted to constant flow. Other investigators proposed perfusion of renal pelvis under controlled pressure, making the method more physiological and reproducible. The objective of the present study was to evaluate the results of the anterograde pressure measurement (APM) of the urinary tract of children with persistent hydronephrosis after surgery suspected to present persistent obstruction.
Along 12 years, 26 renal units with persistent hydronephrosis after surgery (12 PUJ and 14 VUJ) were submitted to evaluation of the renal tract pressure in order to decide the form of treatment. Previous radionuclide scans with DTPA, intravenous pyelographies and ultrasounds were considered undetermined in relation to obstruction in 10 occasions and obstructive in 16. APM was performed under radioscopy through renal pelvis puncture or previous stoma. Saline with methylene blue + iodine contrast was infused under constant pressure of 40 cm H2O to fill the urinary system. The ureteral opening pressure was measured following the opening of the system and stabilization of the water column.
Among the 10 cases with undetermined previous diagnosis, APM was considered non-obstructive in two and those were treated clinically and eight were considered obstructive and were submitted to surgery. Among the 16 cases previously classified as obstructive, nine confirmed obstruction and were submitted to surgery. Seven cases were considered non-obstructive, and were treated clinically, with stable DMSA and hydronephrosis.
APM avoided unnecessary surgery in one third of the cases and was important to treatment decision in 100 %. We believe that this simple test is an excellent diagnostic tool when selectively applied mainly in the presence of functional deficit.
尿路扩张发生在没有梗阻的情况下。依赖肾功能的诊断方法可能会导致误诊。惠特克（1973 年）提出了评估恒流状态下的尿路压力。其他研究人员提出在受控压力下对肾盂进行灌注，使该方法更具生理和可重复性。本研究的目的是评估手术后持续性肾积水患儿的尿路顺行压力测量（APM）结果，这些患儿怀疑存在持续性梗阻。
在 12 年的时间里，26 个接受过手术的持续性肾积水的肾单位（12 个肾盂输尿管连接部和 14 个输尿管膀胱连接部）接受了尿路压力评估，以决定治疗方式。10 次先前的放射性核素扫描、静脉肾盂造影和超声检查被认为与梗阻无关，16 次被认为梗阻。APM 通过经肾盂穿刺或先前造口的放射镜进行。在 40cmH2O 的恒定压力下注入含有亚甲蓝+碘对比剂的生理盐水，以充盈泌尿系统。在系统开放和水柱稳定后，测量输尿管开口压力。
在 10 例先前诊断不确定的病例中，2 例 APM 被认为是非梗阻性的，这些病例接受了临床治疗，8 例被认为是梗阻性的，接受了手术。在 16 例先前被归类为梗阻性的病例中，9 例证实存在梗阻，并接受了手术。7 例被认为是非梗阻性的，接受了临床治疗，DMSA 和肾积水稳定。
APM 避免了三分之一的不必要手术，对 100%的病例的治疗决策具有重要意义。我们认为，当选择性应用于主要存在功能缺陷时，这种简单的测试是一种极好的诊断工具。
