Historically, open ileal ureter replacement (IUR) was a reconstructive option for patients with long-segment ureteral strictures not amenable to primary excision and anastomosis. Although IUR has been shown to be an effective treatment, it is technically challenging to perform and requires bowel reconstruction. With technological advancements in the robotic platform and increasing utilization of more readily accessible substitution tissue, the paradigm has now shifted to favoring robotic substitution ureteroplasty using buccal mucosa graft (BMG) and/or appendix to manage most long-segment ureteral strictures.^1,2 Despite this, the most devastating long-segment ureteral strictures may not be suitable for reconstruction via robotic substitution ureteroplasty using BMG and/or appendix. With regard to BMG ureteroplasty, the technique requires a healthy plate of ureter to sew the BMG onto as the BMG should not be tubularized. Although an augmented anastomotic BMG ureteroplasty may be performed for obliterated defects, the technique still requires that a plate of ureter be anastomosed, which significantly limits the length of stricture that can be repaired using this technique.² With regard to appendiceal ureteroplasty, although the appendix may be interposed an obliterated ureteral defect, the technique is dependent on a patent and sufficiently long appendix, which may not be present.¹ For long-segment ureteral strictures not amenable to reconstruction via substitution ureteroplasty with BMG and/or appendix (Figure 1), IUR remains an important tool in the reconstructive urologist’s armamentarium.

Figure 1. Long-segment ureteral stricture disease not amenable to substitution ureteroplasty with buccal mucosa graft and/or appendix before (A) and after (B) robotic ileal ureter replacement.

IUR was first described in 1906 by Shoemaker,³ and was later popularized by Goodwin et al in the 1950s.⁴ The technique, which is traditionally performed via a midline incision, involves interposing a segment of ileum across a ureteral stricture to allow for unobstructed flow of urine from the kidney to the bladder. IUR is technically challenging as it generally requires a large operative field (manipulation of upper and lower urinary tracts), ureteral identification and assessment of tissue viability (often in the setting of prior surgery, urinoma, and/or radiation), and harvesting a segment of bowel. Although large series have demonstrated that open IUR has been associated with excellent success rates ranging from 69% to 96%,^5,6 it has also been associated with a 29.8% to 42.9% 30-day postoperative complication rate.^5,7 The majority of reported postoperative complications have been infectious (ie, pyelonephritis and intra-abdominal abscess), incisional (ie, dehiscence and hernia), and bowel related (ie, obstruction, internal hernia, and ileus). Although there have been concerns raised about the risk of developing metabolic acidosis due to urinary reabsorption, the reported rate of this complication has been relatively low (2.9%-12%).^5,7 Additionally, most cases of metabolic acidosis may be treated with oral medications, and reoperation is rare.

In an effort to decrease morbidity and improve outcomes associated with open IUR, there have been a handful of reports evaluating the safety and efficacy of robotic IUR. The robotic modality is well suited for complex surgeries such as IUR as it maintains the benefits of minimally invasive surgery such as improved cosmesis, reduced wound complications, and reduced postoperative pain, and enables the surgeon to see in magnified 3-dimensional vision, operate in limited anatomic spaces, and suture with precision. Given the large incision that is generally necessary for open IUR, the robotic modality may reduce wound-related complications and discomfort (Figure 2). Additionally, as many patients requiring IUR suffered an iatrogenic ureteral avulsion and/or radiation damage, periureteral dissection and identification of the remnant ureter may be difficult. Instillation of intraureteral indocyanine green with subsequent visualization under near-infrared fluorescence may assist with identification of the viable proximal ureter/renal pelvis (Figure 3). Also, the complexity of the operation underscores the importance of performing reconstruction with well-perfused tissue. Injection of indocyanine green with subsequent visualization under near-infrared fluorescence may assist with assessment of ureteral perfusion after ureterolysis and bowel perfusion after harvest. We have found that checking perfusion of the harvested bowel to be used for reconstruction of the urinary system provides additional reassurance, especially when anastomosis of the ileum to the proximal ureter/renal pelvis is difficult and more extensive mesenteric mobilization is required. Despite the potential advantages of robotic IUR, the procedure remains technically demanding. The large operative field (Figure 4) may require multiple patient and/or port placement configurations to optimize robotic upper and lower urinary tract access. Additionally, robotic intracorporeal bowel work is associated with a significant learning curve. Although there are no data specifically pertaining to the learning curve for robotic IUR, the literature regarding robotic radical cystectomy with intracorporeal urinary diversion suggests that the learning curve is approximately 140 cases.⁸

Figure 2. Incision made to perform open (A) and robotic (B) right ileal ureter replacement.

Figure 3. A, Difficulty with identification of ureter under white light due to severe periureteral fibrosis. B, Identification of proximal segment of ureter through severe periureteral scar after intraureteral injection of indocyanine green with visualization under near-infrared fluorescence.

Figure 4. Completed ileal ureter demonstrating large surgical field. A, Anastomosis of ileal segment to renal pelvis. B, Anastomosis of ileal segment to bladder.

The current body of literature regarding robotic IUR is limited to small, single-center case series. In the largest series to date, Yang et al reported 15 patients who underwent intracorporeal robotic IUR.⁹ At a median follow-up of 14 months, they reported a subjective success rate (defined as absence of urinary hardware and symptoms, and no radiographic evidence of obstruction) of 100.0%. The authors reported no major (Clavien >2) complications. Although single-institutional reports regarding robotic IUR do provide some insight into the safety and efficacy of the procedure, further studies with larger patient cohorts are necessary. However, generating large robotic IUR series is difficult as patients with long-segment ureteral strictures not amenable to substitution ureteroplasty with BMG and/or appendix are rare. For this reason, we have formed a multi-institutional collaborative with New York University and the University of Colorado. Our unpublished cohort currently consists of 39 patients who underwent intracorporeal robotic IUR. At a median follow-up of 14 months, there was a 90.9% success rate. There was a 20.5% major (Clavien >2) complication rate, which is similar to those reported in the open IUR literature. Through our multi-institutional collaborative, we hope to include more surgeon members to enlarge study populations, assess long-term success rates and complications, and prospectively answer clinically meaningful questions.

Conflict of Interest Disclosures: Z.L. is a consultant for Intuitive Surgical and Boston Scientific and a recipient of educational grants from Intuitive and Kerecis. E.J. has no financial disclosures.