Robot-Assisted Upper Pole Hemi-nephroureterectomy for Vaginal Ectopic Ureter

Summary

A robotic-assisted heminephroureterectomy was performed to address refractory vaginal incontinence resulting from an ectopic ureter in a duplex kidney in a 41-year-old woman with multiple sclerosis, preserving the lower pole and controlling its blood supply with ICG.

Abstract

A duplex kidney with vaginal ectopic ureter insertion is a rare congenital anomaly frequently presenting as refractory urinary incontinence in females and often misdiagnosed as neurogenic bladder or vesicovaginal fistula. The authors describe the case of a 41-year-old female with progressive relapsing-remitting multiple sclerosis (EDSS 6.5), wheelchair dependent, bilateral hip arthroplasties, persistent vaginal leakage, recurrent multidrug-resistant Escherichia coli urinary tract infections, and initial misattribution to neurogenic bladder leading to intermittent self-catheterization. Multimodal imaging—contrast-enhanced CT urography, retrograde pyelography, and MAG3 renal scintigraphy—revealed a right-sided duplex kidney with a non-functioning, hydronephrotic upper pole moiety (0% differential function) and a tortuous megaureter (30 mm diameter) ectopically draining into the vaginal vault. Following percutaneous nephrostomy for decompression and antibiotic treatment for infection control, robotic-assisted upper pole heminephroureterectomy was performed. Indocyanine green fluorescence guidance enabled precise upper pole resection. The ectopic ureter was traced and excised distally. The procedure lasted 90 min with 50 mL blood loss and no intraoperative complications. The postoperative course was also uneventful. The 12-month follow-up demonstrated complete resolution of incontinence with high patient satisfaction. This case illustrates the diagnostic challenges of ectopic ureters in adults with neurological impairment and demonstrates the feasibility and favorable outcome of robotic surgery for complex congenital urogenital anomalies in high-risk patients.

Introduction

Duplex collecting systems are the most common congenital renal anomaly, affecting approximately 0.8% of the population¹. Ectopic ureters are rarer (0.025–0.05%) but are associated with duplex systems in up to 80% of cases², predominantly involving the upper pole moiety according to the Weigert-Meyer rule, whereby the upper pole ureter inserts medially and inferiorly and frequently drains ectopically into the vagina, urethra, or vestibule in females. Embryological maldevelopment of the ureteric bud leads to ectopic insertion, obstruction, hydronephrosis, and continuous urinary leakage (Figure 1). In females, vaginal drainage commonly manifests as persistent incontinence, often misdiagnosed as neurogenic bladder, vaginal discharge, or fistula—especially in adulthood, where nearly 30% of cases are diagnosed after age 18³.

Standard treatment for poorly functioning moieties is surgical excision, with robotic-assisted laparoscopic heminephroureterectomy increasingly preferred over open or laparoscopic approaches due to enhanced precision, minimized blood loss, decreased hospitalization duration, and minimal complications^4,5. Indocyanine green (ICG) fluorescence further improves vascular identification and tissue preservation^6,7. This article is suitable for specialists who treat uncommon congenital conditions in intricate cases.

Case Presentation:

A 41-year-old female, wheelchair-dependent due to progressive relapsing-remitting multiple sclerosis (EDSS 6.5) and bilateral hip arthroplasties, presented with continuous vaginal urinary leakage, recurrent urinary tract infections (multidrug-resistant Escherichia coli), intermittent lower abdominal pain, and episodic fever (up to 38.5 °C). Symptoms were initially attributed to neurogenic bladder secondary to multiple sclerosis, leading to initiation of intermittent self-catheterization and reliance on incontinence pads. This conservative approach exacerbated social withdrawal, psychological distress, and recurrent infections. Diagnostic evaluation included contrast-enhanced CT urography demonstrating a right duplex kidney with severe hydronephrosis of a non-functioning upper pole moiety and a tortuous, dilated ectopic megaureter (30 mm) inserting into the vaginal vault (Figure 2), retrograde pyelography confirming the ectopic insertion, and MAG3 scintigraphy verifying 0% differential function of the upper pole (preserved lower pole function: 33% of the total renal function). Percutaneous nephrostomy placement achieved decompression of hydronephrosis over four weeks.

Diagnosis, Assessment, Plan:

Right-sided duplex kidney with vaginal ectopic ureter from a non-functioning upper pole moiety causing continuous incontinence and recurrent pyelonephritis. Differential diagnosis included neurogenic bladder dysfunction, vesicovaginal fistula, or single-system ectopic ureter. Multimodal imaging (CT urography, retrograde pyelography, MAG3 scintigraphy) showing obstruction, megaureter, absent upper pole function, and vaginal insertion bypassing sphincter control. Initial temporary diversion with percutaneous nephrostomy and targeted antibiotics to resolve infection and inflammation, followed by definitive robot-assisted upper pole heminephroureterectomy. The robotic approach was selected for superior visualization and precision. ICG fluorescence was planned to safeguard the lower pole vascular supply. Anticipated complications (bleeding, lower pole ischemia, infection recurrence) were minimized through fluorescence-guided dissection and an experienced robotic team.

Protocol

The patient consented in writing to all treatment steps and anonymous publication. The study complies with the Declaration of Helsinki and was approved by the ethics committees of the Westfalen-Lippe Medical Association and the University of Muenster (2023–500-f-S) for retrospective data management. All the materials used in this case report are listed in the Table of Materials.

1. Perioperative preparation

1. Antibiotic prophylaxis with a single-dose intravenous cephalosporin was administered 30 min prior to skin incision.
2. Venous thromboprophylaxis with subcutaneous low-molecular-weight heparin was initiated the night before surgery and continued daily for three weeks post-discharge.
3. A Foley catheter was placed in the bladder and inflated with 10 mL of saline.

2. Patient positioning

1. After the introduction of general anesthesia, the patient was then positioned in lateral decubitus to facilitate optimal exposure of both the upper abdomen and the pelvis.
2. The patient was securely fastened to the operating table to prevent shifting.

3. Trocar placement and robot docking

1. Pneumoperitoneum was established (12 mmHg) through a mini-laparotomy paraumbilically.
2. A standard transperitoneal renal robotic configuration was used: a cranial paraumbilical camera port and three additional trocars on a pararectal line, one cranial trocar for bipolar forceps, and two caudal trocars.
3. The first one, next to the camera port, was used for the monopolar scissors, and the most caudal one was used for the robotic grasping instrument. Trocars were arranged in a curved arc toward the renal pelvis and the ureter, maintaining 8 cm spacing between them.
4. The robotic system was docked from a lateral approach. Instruments included monopolar scissors, fenestrated bipolar forceps, robotic surgical forceps, and a needle holder.

4. Robotic-assisted heminephrectomy

1. The right colon was mobilized medially. Gerota’s fascia was incised to expose the duplex kidney using the robotic monopolar scissors.
2. The renal hilus was exposed, and the renal vessels were isolated.
3. Vascular Identification with Indocyanine Green (ICG): After isolating the upper pole vascular pedicle, two small arteries were clamped, and intravenous indocyanine green was administered to identify the inferior moiety’s blood supply and preserve it.
4. After planning the resection line, the upper moiety vessels (two small arteries and one vein) were clipped and transected.
5. Upper pole resection: To prevent bleeding from the resection line between the two moieties, the arteries of the lower pole moiety were closed with a clamp.
6. After delineating the resection line between the two moieties, the upper pole moiety was dissected and excised from the under moiety using the robotic monopolar scissors.
7. Then a rennoraphy was performed using a 3-0 monofilament suture in a running technique using the robotic needle holder (Figure 3).
8. The clamps were removed to allow circulation through the lower pole-moiety artery.
9. The blood supply to the preserved moiety was again checked using ICG, and it appeared normal (Figure 4).

5. Upper moiety ureteral dissection and excision

1. The ectopic ureter was traced distally to its vaginal insertion using the monopolar robotic scissors and the bipolar forceps (Figure 5).
2. The ureter was resected as low as possible to eliminate any residual stump. The vaginal orifice of the ureter was closed with a clip.

6. Control of the blood supply and closure

1. ICG was used to control the circulation of the preserved tissue under the moiety and its ureter to the ureterovesical junction. The entire unit appeared to have an adequate blood supply.
2. Hemostasis was verified. No drain was placed. Ports were removed under vision. The fascia was closed with a running suture using a 1-0 Vicryl.
3. The Foley catheter was left intact in the bladder and was removed on the first postoperative day.

Results

The robotic heminephroureterectomy was performed successfully without any intraoperative or immediate postoperative complications. The operative duration was 90 min with an estimated blood loss of 50 mL. Renal ultrasound performed at 2 weeks post-surgery confirmed resolution of hydronephrosis and preserved function of the lower pole. A CT scan at 10 weeks postoperatively demonstrated a morphologically intact renal unit exhibiting normal contrast enhancement and unobstructed urinary flow through the ureter, which appeared morphologically unaltered (Figure 6). At the 12-month follow-up, the patient reported complete resolution of vaginal leakage and no further urinary tract infections. She expressed high satisfaction with the outcome and no worsening of multiple sclerosis symptoms. Long-term renal function monitoring (split renal function on the right at 33%) showed no decline from preoperative levels.

Figure 1: Duplex kidney development. According to the Weigert-Meyer rule: (1) Formation of dual ureteric buds; (2) Ascent and medial/inferior shift of upper pole ureter; (3) Completed duplex system with ectopic upper pole ureter. This figure was created using Google's Gemini (Google LLC). The authors reviewed, modified as necessary, and assume full responsibility for the final content. No copyright concerns are involved. Please click here to view a larger version of this figure.

Figure 2: Preoperative CT urography. Coronal computed tomography (CT) images demonstrating a right duplex kidney with a severely hydronephrotic, non-functioning upper pole moiety (left) and the markedly dilated ectopic ureter/megaureter (right). Please click here to view a larger version of this figure.

Figure 3: Renorrhaphy. Intraoperative screenshot of the suture line after renorrhaphy following resection of the upper pole moiety. Please click here to view a larger version of this figure.

Figure 4: Preserved lower pole moiety. Intraoperative indocyanine green (ICG) fluorescence confirms preserved perfusion of the lower pole moiety following heminephrectomy. Please click here to view a larger version of this figure.

Figure 5: Vaginal ectopic ureter. Intraoperative screenshot showing distal ectopic ureter insertion in the vaginal vault. Please click here to view a larger version of this figure.

Figure 6: Postoperative CT scan. Sagittal computed tomography (CT) image demonstrating preservation of the remaining right renal parenchyma following upper pole heminephroureterectomy, without evidence of postoperative obstruction. Please click here to view a larger version of this figure.

Discussion

The diagnostic journey in this case highlights the considerable challenges posed by congenital ureteral anomalies presenting in adulthood^1,2, particularly when superimposed on pre-existing neurological conditions. In this patient, the presence of multiple sclerosis with established neurogenic bladder dysfunction created a diagnostic trap, leading to years of conservative management with intermittent catheterization and incontinence pads before the true anatomical anomaly was identified. This delay not only prolonged patient suffering but also permitted recurrent episodes of pyelonephritis and progressive upper tract deterioration, ultimately resulting in complete loss of upper pole function by the time of definitive diagnosis. The case underscores the critical importance of maintaining a high index of suspicion for congenital anomalies in adults with refractory incontinence, even when seemingly adequate explanations for symptoms exist.

The preoperative multimodal imaging strategy employed in this case proved essential for accurate anatomical delineation and surgical planning. Contrast-enhanced CT urography provided excellent visualization of the duplex system. The retrograde pyelography confirmed the ectopic insertion site, while MAG3 renal scintigraphy quantified the functional contribution of each moiety, confirming 0% differential function of the upper pole and establishing the lower pole's preserved function at 33% of total renal function. This comprehensive imaging approach is particularly valuable in complex cases where the anatomy may be distorted by chronic obstruction or recurrent infection, and it aligns with contemporary recommendations advocating for multimodality assessment prior to surgical intervention^8,9.

The robotic surgical approach addressed several technical challenges inherent to this case, including the patient's significant comorbidities and the complex vascular anatomy of duplex kidneys. The patient's wheelchair dependence due to multiple sclerosis and bilateral hip arthroplasties necessitated careful positioning and secure fixation on the operating table, but did not preclude successful robotic intervention. The lateral decubitus positioning provided optimal access to both the renal fossa and the pelvic ureteral insertion, demonstrating the versatility of the robotic platform in managing anomalies spanning the entire retroperitoneal space⁷. ICG fluorescence guidance proved invaluable for precisely identifying the vascular supply to the lower pole moiety, allowing for selective clamping of the two small arteries supplying the upper pole while preserving perfusion to the functional renal tissue^10,11. This technique, which has been increasingly adopted in robotic urologic surgery, enabled confident resection with minimal risk of ischemic injury to the preserved moiety^6,7,12. The ability to verify perfusion both before and after resection using ICG provided real-time reassurance of lower pole viability and contributed to the zero-complication outcome.

The operative outcomes in this case compare favorably with published series of laparoscopic and robotic heminephrectomy in adults^4,5. The operative time of 90 minutes, estimated blood loss of 50 mL, and absence of intraoperative complications reflect the benefits of robotic assistance. These technical advantages are particularly relevant in cases requiring meticulous dissection around the renal hilum and extensive ureteral mobilization down to the vaginal insertion. While previous reports have described laparoscopic approaches to similar pathology⁵, the robotic platform appears to offer advantages in terms of precision and surgeon comfort, especially when operating in confined spaces or when extensive ureteral dissection is required. The patient's hospital stay of four days was appropriate given her baseline functional limitations and the extent of the procedure, and the absence of postoperative complications suggests that the robotic approach is well-tolerated even in patients with significant neurological impairment.

The management of the ectopic ureter required particular attention to ensure complete resolution of incontinence without leaving a residual stump that could serve as a nidus for infection or continued leakage. The ureter was traced distally to its vaginal insertion and resected as low as possible, with the vaginal orifice closed using a surgical clip. The functional lower pole ureter was preserved intact to the ureterovesical junction, as confirmed by ICG fluorescence demonstrating adequate perfusion along its entire course. The 12-month follow-up confirms the durability of this approach, and the stable renal function (33% split function on the right) indicates that the preserved lower pole is providing adequate drainage without obstruction or reflux.

In this 41-year-old patient with multiple sclerosis and a duplex kidney with a non-functioning upper pole moiety and vaginal ectopic megaureter, robotic-assisted heminephroureterectomy with ICG fluorescence guidance resulted in complete resolution of incontinence and recurrent infections, with preserved lower-pole renal function at 12 months. While these results are encouraging for this individual patient, they should not be interpreted as establishing the general safety and efficacy of robotic heminephroureterectomy across all patient populations, as outcomes depend heavily on patient-specific anatomy, surgeon expertise, and institutional resources. Further studies in larger, more diverse cohorts are necessary to define the role of this approach in the broader management of complex congenital urogenital anomalies in adults.

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Bulldog Clamp	Cmed	399-100-799	Vessels closure clamp
da Vinci Xi robotic system	Intuitive Surgical	https://www.intuitive.com/en-in/products-and-services/da-vinci/xi	Robotic system
Indocyanine green (ICG) dye	Diagnostic Green GmbH	https://diagnosticgreen.com/row/icg-pharmaceutical-product/	25 mg vial
Monocryl 3-0	Ethicon	D9645	Absorbable suture used for renorraphy
Transurethral Foley catheter	B. Braun Melsungen AG	https://catalogs.bbraun.com/en-01/c/PRODUCTS0000000976/urinary-catheters	16 Fr, 2-way
Vicryl 1-0	Ethicon	VP2347	Absorbable suture used for Fascia Closure