Assuming this is a Grade 3 or 4 hydronephrosis, it is very likely to be an intermittent obstruction in an over 5-6 yrs old patient. If the flank pain is clear, and if the severity of hydronephrosis on ultrasound is increasing during pain, the chances of finding a crossing-vessel intermittently obstructing upper ureter is high. So, the real pain and severe hydronephrosis are two solid indications for surgery. On laparoscopic exploration, if I do not see a crossing vessel, I perform a regular pyeloplasty. If there is a crossing vessel that obstructs UPJ, than I perform a vascular hitch procedure popularized by Imran Musthaq. Very simple, takes less than 60 minutes, no drains and very effective. (Sakoda, A., Cherian, A. and Mushtaq, I. (2011), Laparoscopic transposition of lower pole crossing vessels (‘vascular hitch’) in pure extrinsic pelvi-ureteric junction (PUJ) obstruction in children. BJU International, 108: 1364–1368. doi: 10.1111/j.1464-410X.2011.10657.x ).

I also attached a short video of my first case from three years ago (sorry for the quality).

@Ibrahim Ulman: Thanks for your answer. If the EC renal scan shows non obstructive pattern and in diagnostic laparoscopy you do not see crossing vessel why do you choose pyeloplasty? Do you expect that the flank pain improve after that?!

I'd be happy to know the degree of hydronephrosis and the age in your case. If it is severe, and if the pain is unquestionable, I would definitely do a pyeloplasty. Even if it does not look like a ''typical'' obstructive UPJ, some people still believe, or prefer to believe the classical old theory of an ''aperistaltic'' segment which cannot be documented microscopically. Whatever the pathophysiologic explanation is, given the above conditions; in my experience, the outcome has always been satisfactory. But still, your chance of finding a crossing-vessel is high.

Symptomatic hydronephrosis is a clear cut indication for surgical correction. So no confusion.

If there is any doubt about the origin of the pain whether it is of renal origin or not, one may put a DJ stent and if the pain resolves can proceed with pyeloplasty

IN THE IVP, IF EMPTYING OF THE KIDNEY IN THE DELAYED FILMS IS EVIDENT, THEN NOTHING SHOULD BE DONE EXCEPT FOLLOW UP PARTICULARLY WITH NON OBSTRUCTIVE RENAL SCAN .

In intermittent hydronephrosis with pain, the scan may show  no obstruction. If there is dilatation at the time at the time of pain, a pyeloplasty should be done. I do not  recommend a vascular hitch since there are no objective methods to determine who has an associated intrinsic obstruction

The patient is symptomatic. It´s an indication for surgery. What kind of scintigraphy examination did you perform? 

We some adjunctive informations: the degree of dilation (antero-posterior diameter), calyces involvement, what kinder of

In such cases intermittent hydronephrosis may be the cause. So F-15 diuretic renogram is indicated. If this study shows obstruction, most prbably a crossing vessle is the cause and pyeloplasty with transposition of thr UOJ anterior to tge vessle is the best treatment

I Agree with Sumit Sharma, it is a case where a double J stent can help to show the origin of pain. and if the pain resolves, a pyeloplasty is a good choice.

Laparoscopic pyeloplasty is the standard. However I will perform percutaneous endopyeloplasty. here is the video attached.

http://youtu.be/QdNzcIlOcG8

The EC scan was probably taken during the non symptomatic phase of intermittent hydronephrosis. does the EC scan show decrease in differential left renal function. was it a diuretic nuclear renal scan. it would be helpful if you provide the complete details of ivu and ec scan.

simply put 1. presence of symptoms and decrease in function are indications for intervention.

I think it is better to show the images. I believe if a patient has loin pain and hydronephrosis on IVU and u/s, that should be evident using diuretic renogram. 

I have had a couple of cases of intermittent pain and hydronephrosis caused by aberrant crossing vessel(s) without stenosis. So a CT (or MR) angiography would be helpful for the correct diagnosis and treatment.

Cuando aparecen los síntomas y sus complicaciones,en este caso en particular el estudio propuesto por mis colegas,pero la alternativa es la pieloplastia sea cualquier via o técnica,lo principal es de conservar lo antes posible que no se deteriore la función real,que en definitiva es lo que tenemos que cuidar y conservar.

Aclaro la respuesta porque  la traducción  no es correcta:

-Realizar pieloplastia

-Para conservar función renal

-Con,uiv,ecografia y renograma diurético estoy de acuerdo

I would go with Pyeloplasty and expect higher rates of crossing lower pole vessel