to stent or not to stent  is a point debated since long time . this assumes importance in children and infants requiring intervention for ureteropelvic junction obstruction ( upjo ) . although literature supports  stentless  pyeloplasty , in laparoscopic pyeloplasty particularly , it is a common practice to stent the anastomosis . the advantages and disadvantages of both the approaches are well known . in infants , the urethra is narrow and runs the risk of injury and subsequent strictures with surgical manipulations . in addition , the stent - related morbidities which include dysuria and infections may make the postoperative course of the infant unpleasant . in the days of open surgery , it was our policy to employ the technique of open insertion of stent along with a nephrostomy , just prior completion of the anastomosis . this served the purpose of nephrostomy acting as a safety valve prior to removal of splint . in this article , we describe the technique of ante grade access of the ureter , thus potentially avoiding the urethral manipulations and the associated complications . a 7.5mhz ( b  k medical , denmark ) ultrasound probe with puncture attachment is used . a pediatric probe is used for this purpose [ figure 1 ] . a 18 gauge echotip disposable two part trocar needle ( cook urological inc , indiana , usa ) which is available as a two part needle was used . a 0.035 guide wire or alternatively a terumo glide wire ( terumo corporation , tokyo , japan)with alken two part metallic needle helps simultaneously passing two guide / glide wires [ figure 1 ] . the dilatation is done with angiotech one step dilator ( pbn medicals , denmark ) , a14 fr nephrostomy tube ( devon innovations ( p ) ltd , parwanoo , hp , india ) with a 5 fr open end ureteric catheter ( devon innovations ( p ) ltd , bangalore , india ) is used . the armamentarium ( a ) telescopic metal two part needle ( b ) pediatric ultrasound probe the first step involves positioning the patient in a prone position , although the same can be done in supine position . line diagram ( a ) and picture ( b ) illustrating ultrasound - guided calyceal puncture the needle is housed in the needle attachment of the ultrasound probe and the posterior calyx identified [ figure 2 ] . the  key  for a successful ultrasound puncture is that the needle should be seen throughout the trajectory which includes the skin , subcutaneous tissue , cup of the calyx and the calyx in concern [ figure 3 ] . technique of ultrasound - guided access ( a ) an egress of clear fluid suggesting entry in the pelvicalyceal system ( b ) a successful ultrasound puncture - the needle should be seen throughout the trajectory which includes the skin , subcutaneous tissue , cup of the calyx and the calyx in concern an egress of clear fluid suggests entry in the pelvicalyceal system which can further be confirmed with a contrast study [ figure 3 ] . next a guide wire is parked in a distant calyx and the tract dilated up to 14 fr using a screw dilator . an alken needle , which is a two part needle , helps in passing a second guide wire after removing the inner stylet [ figure 4 ] . once both guide wires are in place , one wire is used for passing a ureteric catheter and the second one is used for placing a nephrostomy tube [ figure 5 ] . the salient feature of our technique is that all steps of percutaneous access which include access and dilation are done solely using ultrasound guidance . ( a ) the needle and guide wire are clearly seen in real time ultrasound , thus avoiding bowel injury ( b ) ( line diagram ) and c ( picture):-two glide wires passed into the renal pelvis through the telescopic metal two part needle after removing the inner stylet ( a ) line diagram showing completed anastomosis with nephrostomy and ureteric catheter ( splint ) in situ , ( b ) laparoscopic pyeloplasty performed after the ureteric catheter and percutaneous nephrostomy is in place c ) opened up renal pelvis showing presence of both malecot catheter and ureteric catheter in pelvis ( d ) ultrasound showing flower of malecot catheter opened in pelvis after the ureteric catheter and percutaneous nephrostomy is in place , the laparoscopic pyeloplasty is performed . once the pelvis is opened and the ureter spatulated , the ureteric catheter which is already coiled in the pelvis is passed under direct vision into the ureter after the posterior layer is completed following which the anastomosis is completed [ figure 6 ] . placement of ureteric splint under vision once the posterior wall is completed , the ureteric catheter is passed into the ureter under vision ureteric catheter is removed on the 3 post operative day and nephrostomy is clamped . the modified technique was successfully done in five patients aged less than one year old . a 7.5mhz ( b  k medical , denmark ) ultrasound probe with puncture attachment is used . a pediatric probe is used for this purpose [ figure 1 ] . a 18 gauge echotip disposable two part trocar needle ( cook urological inc , indiana , usa ) which is available as a two part needle was used . a 0.035 guide wire or alternatively a terumo glide wire ( terumo corporation , tokyo , japan)with alken two part metallic needle helps simultaneously passing two guide / glide wires [ figure 1 ] . the dilatation is done with angiotech one step dilator ( pbn medicals , denmark ) , a14 fr nephrostomy tube ( devon innovations ( p ) ltd , parwanoo , hp , india ) with a 5 fr open end ureteric catheter ( devon innovations ( p ) ltd , bangalore , india ) is used . the armamentarium ( a ) telescopic metal two part needle ( b ) pediatric ultrasound probe the first step involves positioning the patient in a prone position , although the same can be done in supine position . line diagram ( a ) and picture ( b ) illustrating ultrasound - guided calyceal puncture the needle is housed in the needle attachment of the ultrasound probe and the posterior calyx identified [ figure 2 ] . the  key  for a successful ultrasound puncture is that the needle should be seen throughout the trajectory which includes the skin , subcutaneous tissue , cup of the calyx and the calyx in concern [ figure 3 ] . technique of ultrasound - guided access ( a ) an egress of clear fluid suggesting entry in the pelvicalyceal system ( b ) a successful ultrasound puncture - the needle should be seen throughout the trajectory which includes the skin , subcutaneous tissue , cup of the calyx and the calyx in concern an egress of clear fluid suggests entry in the pelvicalyceal system which can further be confirmed with a contrast study [ figure 3 ] . next a guide wire is parked in a distant calyx and the tract dilated up to 14 fr using a screw dilator . an alken needle , which is a two part needle , helps in passing a second guide wire after removing the inner stylet [ figure 4 ] . once both guide wires are in place , one wire is used for passing a ureteric catheter and the second one is used for placing a nephrostomy tube [ figure 5 ] . the salient feature of our technique is that all steps of percutaneous access which include access and dilation are done solely using ultrasound guidance . ( a ) the needle and guide wire are clearly seen in real time ultrasound , thus avoiding bowel injury ( b ) ( line diagram ) and c ( picture):-two glide wires passed into the renal pelvis through the telescopic metal two part needle after removing the inner stylet ( a ) line diagram showing completed anastomosis with nephrostomy and ureteric catheter ( splint ) in situ , ( b ) laparoscopic pyeloplasty performed after the ureteric catheter and percutaneous nephrostomy is in place c ) opened up renal pelvis showing presence of both malecot catheter and ureteric catheter in pelvis ( d ) ultrasound showing flower of malecot catheter opened in pelvis after the ureteric catheter and percutaneous nephrostomy is in place , the laparoscopic pyeloplasty is performed . once the pelvis is opened and the ureter spatulated , the ureteric catheter which is already coiled in the pelvis is passed under direct vision into the ureter after the posterior layer is completed following which the anastomosis is completed [ figure 6 ] . placement of ureteric splint under vision once the posterior wall is completed , the ureteric catheter is passed into the ureter under vision ureteric catheter is removed on the 3 post operative day and nephrostomy is clamped . the modified technique was successfully done in five patients aged less than one year old . the indications for stenting are well known , they include pyeloplasty in the presence of solitary functioning kidney , infection , or a previous failed procedure . placing a stent in a retrograde fashion involves urethral manipulation and the attendant complications ; in addition , this involves an additional procedure for removal of the stent . the advantages of stent placement following pyeloplasty include decreased risk of collection or edema , maintaining ureteric alignment woo et al . , in their study on the impact of internal stenting on the surgical outcome of dismembered pyeloplasty in infants under the age of 12 months with the open approach . they observed statistically significant increase in urinary leaks , length of hospital stay and need for repeat pyeloplasty in non stented versus the stented group . a variety of techniques have been described to place a stent or a splint antegrade thus avoiding the need for cystoscopy during insertion or removal . taveres et al describe a technique for inserting an internal - external nephroureteral antegrade stent during laparoscopic pyeloplasty which can be removed in clinic as outpatient . the advantages of the technique we have described are the following : 
 1)the ureteral access can be gained with ultrasound guidance . this minimizes the risk of bowel injury as well radiation in these patients.2)the nephrostomy tube acts as a safety valve and can be clamped to confirm the integrity of the anastomosis prior to its removal.3)if needed , the ureteric catheter can act as conduit to negotiate a ureteral stent across the anastomosis . the nephrostomy tube acts as a safety valve and can be clamped to confirm the integrity of the anastomosis prior to its removal . if needed , the ureteric catheter can act as conduit to negotiate a ureteral stent across the anastomosis . we acknowledge that there are a few disadvantages with this technique and the most significant is the need for additional equipment and expertise for gaining percutaneous renal access . in addition , at times , repeated attempts for gaining access lead to extravasation and oozing , which might hamper the vision and the anastomosis . in infants with pelviureteric junction obstruction when undergoing laparoscopic pyeloplasty ; ultrasound - guided antegrade nephroureteric , ureteric catheter placement is a safe technique . it avoids need for urethral manipulation for insertion and removal of stent , decreases radiation exposure to infant . furthermore , nephrostomy tube acts as a safety valve to confirm the integrity of anastomosis and ureteric catheter may act as conduit to put another ureteric stent if necessary at later date . this technique requires some additional equipments and expertise to get percutaneous renal access which can be mastered with practice .