Da Vinci Walks the Pebbled Streets of a Primary Obstructed Megaureter with Ureterocele

Abstract

Introduction: Primary obstructed megaureter (POM) usually refers to primary dilated ureters in which vesicoureteral reflux and other secondary causes of lower ureteral obstruction have been ruled out. We herein present a case of obstructed megaureter with a dilated saccular lower end representing an ureterocele and concomitant multiple multifaceted stones almost completely filling the dilated tortuous ureter of a normally functioning and excreting kidney.

Materials and Methods: Our index case was a 45-year-old lady with intermittent right flank pain for a year with acute colic since a week. Imaging revealed a grossly dilated tortuous ureter with >50 multifaceted stones all along its length, an ureterocele, and mild hydronephrosis. She underwent a robot-assisted ureterolithotomy and complete stone clearance followed by ureteral reimplantation over an ureteral stent.

Results: Postoperative course was uneventful and on follow-up at 3 weeks, stent was removed after checking a cystogram. The da Vinci system with its minimally invasive approach and better ergonomics made it quite convenient to remove all 52 stones, ensuring an excellent postoperative recuperation and incomparable cosmesis.

Conclusion: POM in adults is usually symptomatic and associated with complications, and surgery remains the mainstay of treatment when it is associated with calculi. Ureteral tailoring and ureteroneocystostomy with extraction of stones were done for at-risk kidneys and to prevent further renal deterioration. However, these efforts appear futile when the severe renal impairment has set in and nephroureterectomy is thus required. The robotic approach for reconstruction is a safe, effective, and feasible option with excellent perioperative results.

Introduction

The term “megaureter” denotes a dilated ureter irrespective of cause. Originally coined by Chaulk in 1923 as “megaloureter,” the term megaureter is defined as a ureter with a diameter of >7 mm.¹ Although most commonly seen as a congenital variant presenting in neonates and children, its incidence in adults is rare and is usually diagnosed when the patient presents with urolithiasis, pain, renal deterioration, or urinary tract infections.

It is classified as either being obstructed or nonobstructed and/or refluxing and nonrefluxing. The term primary obstructed megaureters (POMs) is usually used for primary dilated ureters in which vesicoureteral reflux and other secondary causes of lower ureteral obstruction have been ruled out. It is hypothesized to be because of a functional obstruction that occurs at or near the vesicoureteric junction, resulting in an adynamic aperistaltic segment of lower ureter with upstream dilation.

Usually, POM regresses spontaneously in childhood. When diagnosed in adults, it is usually because of failure of this spontaneous regression and is unilateral in most cases. When associated with calculi, it represents a challenging scenario as distinguishing it from hydroureteronephrosis secondary to obstructive calculi is difficult.

We herein present a case of obstructed megaureter with a dilated saccular lower end representing a ureterocele and concomitant multiple multifaceted stones all along the length of the dilated tortuous ureter of a normally functioning and excreting kidney, which was managed with robotic ureterolithotomy and ureteral reimplantation.

Materials and Methods

A 45-year-old lady with no comorbidities and no significant history of stone formation presented with intermittent right flank pain for the past 1 year with severe colic since the past 1 week. Systemic and urogenital examinations were normal. An ultrasonography of the abdomen revealed multiple ureteral calculi with dilated right pelvicaliceal system.

Urine routine and microscopic examinations were within normal limits and the urine culture showed no growth. Serum creatinine was within normal limit and she underwent a contrast-enhanced CT scan that revealed a moderately hydronephrotic right kidney with a dilated tortuous ureter and multiple (∼30–35) stones and a dilated saccular out pouching of the right lower ureter of size 4 × 3 cm, suggestive of an ureterocele. The kidney architecture, enhancement, and excretion were all preserved (Figs. 1 and 2)

FIG. 1.

Plain (a) and contrast (b) CT scan; coronal sections showing the row of ureteral stones on the right side with hydroureteronephrosis and normally enhancing right kidney.

FIG. 2.

(a–c) Reconstructed images depicting the ureteral calculi, ureterocele, and the ureteral dilation and tortuosity.

She underwent a robot-assisted laparoscopic ureterolithotomy with clearance of all ureteral stones followed by a ureteral reimplantation by a nonrefluxing modified Lich–Gregoir method on the right side. This was accomplished using the da Vinci Xi Robot system and a standard four-port placement. Initially, pelvic docking was done to clear the stones from the lower ureter followed by lateral docking for upper ureteral stone clearance. A 6F Double-J stent was placed across the anastomosis and the ureterolithotomy site. Stone clearance was confirmed by flouroscopy. A total of 52 stones of various shapes and sizes were retrieved. Total console time was 260 minutes with a minimal blood loss of ∼100 mL. Postoperative course was uneventful with drain removed on day 2 and patient was discharged on day 3. On follow-up at 3 weeks, Foley's catheter was removed and a cystogram confirmed a normal bladder capacity and no contrast extravasation. The Double-J stent was also removed subsequently. The patient is doing well and is pain free on 4 weeks follow-up (Fig. 3).

FIG. 3.

Surgical procedure (a) incising the lower right ureter, (b) extraction of stones from lower ureter, (c) ureterovesical anastomosis, (d) stent being placed across the ureterolithotomy site, (e) endoscopic view of the right ureterocele, (f) postoperative picture showing the 52 stones extracted.

Discussion

POMs rarely occur in adults and is usually asymptomatic. When symptomatic, the most common underlying causes are calculi, infections, or renal failure. It occurs mostly in males and is unilateral in ∼75% of the cases, most commonly occurring on the left side. The primary etiology attributed is an aperistaltic segment at the lower ureter causing functional obstruction and upstream hydroureteronephrosis.²

There is controversy regarding the definition of megaureter. However, the British association of pediatric urologists¹ defines it as a ureteral diameter of >7 mm. The mainstay of diagnosis remains radiology. The diagnostic criteria for POM include a dilated ureter with or without distal tapering with no vesicoureteral reflux, no bladder outlet obstruction and secondary causes of lower ureteral obstruction being ruled out.^1,2

CT urography and intravenous pyelography are the imaging modalities of choice in the presence of urolithiasis. They reveal dilated ureters with distal narrowing and the presence of calculi that can be present either in the ureter or in the calices. In our case, the lower end of the ureter had a saccular out pouching suggestive of a ureterocele and there was presence of multiple large ureteral calculi. The presence of these calculi made it difficult to ascertain the diagnosis of POM and distinguish it from hydroureteronephrosis secondary to calculi.

The treatment modalities depend on the functional status of the involved kidney.³ If kidney is functional, the gold standard remains ureteral remodeling and ureteroneocystostomy after excising the involved lower end of the ureter. When there is severe renal impairment, nephroureterectomy is required. In cases presenting with urolithiasis, the stones are extracted at the time of ureteroneocystostomy. In our case, the kidney was functional as shown by CT scan and there were multiple ureteral stones all along the length of the ureter. This required an additional ureterolithotomy for extraction of all the stones.

There have been previous case reports with giant calculi in megaureters that were treated based on the renal functionality. In the study by Delakas et al., nephroureterectomy was performed as it was a nonfunctioning kidney, whereas in the study by Demirtas et al., stone extraction and ureteroneocystostomy were done for a 6 cm stone.

Recently, the use of laparoscopic and robotic approaches has been in vogue for lower ureter reconstructive procedures.⁴ This is because of reduced intraoperative difficulty in terms of ease of reconstruction and also reduced perioperative morbidity. Our case was challenging as all the stones could not be extracted after incising the lower ureter and an additional ureterolithitomy had to be done to extract the upper ureteral stones. The da Vinci system with its minimally invasive approach, excellent 3D vision, and better ergonomics made it quite convenient to remove all 52 stones, ensuring a complete stone clearance and better postoperative recuperation and incomparable cosmesis.

Conclusion

POM in adults is usually symptomatic and associated with complications, and surgery remains the mainstay of treatment when it is associated with calculi. Ureteral tailoring and ureteroneocystostomy with extraction of stones are done for at-risk kidneys and to prevent further renal deterioration. However, these efforts appear futile when severe renal impairment has set in and nephroureterectomy is thus required. Robotic approach for reconstruction is a safe, effective, and feasible option with excellent perioperative results.

Abbreviations Used

CT

computed tomography

POM

primary obstructed megaureter

Disclaimer

The article has been read and approved by all the authors, the requirements for authorship as stated earlier in this document have been met, and each author believes that the article represents honest work. The article has not been published in part or whole or is not under consideration for publication elsewhere in any language.

Disclosure Statement

No competing financial interests exist.

Funding Information

No funding was received for this article.

Cite this article as: Talwar HS, Kumar S, Narain TA, Panwar VK, Mittal A, Navriya S, Bhirud DP (2020) Da Vinci walks the pebbled streets of a primary obstructed megaureter with ureterocele, Journal of Endourology Case Reports 6:4, 358–361, DOI: 10.1089/cren.2020.0111.