Retroperitoneal Versus Transperitoneal Approach

The UPJ can be accessed via a transperitoneal or retroperitoneal route. Although most laparoscopic or robot-assisted urological surgeries are performed transperitoneally, there may be unique advantages with the retroperitoneal approach as it provides direct access to the renal pelvis and hilar vessels without the need for colonic reflection, avoids urine leak into the peritoneal cavity, and potentially hastens recovery. This may also be the approach of choice in obese patients or those who have had multiple prior abdominal surgeries. Outcomes of both retroperitoneal and transperitoneal approaches appear similar. The original description of retroperitoneal RAP was in the pediatric population in 2004 [35]. Subsequently the first report in adults was by Kaouk and colleagues in 2008 [36]. In this series, all cases were performed by a single surgeon with prior experience in retroperitoneal LP. Retroperitoneal access was achieved through a 1.2-cm incision at the tip of the 12th rib and subsequently, the lumbodorsal fascia incised and retroperitoneal space developed by balloon dissection. The authors indicate that although the transperitoneal approach affords the advantage of familiarity of the operative field, and a larger working space, there are significant benefits for the retroperitoneal approach such as lower risk of bowel injury and direct approach to the UPJ. In retroperitoneal LP series, the technical challenge of intracorporeal suturing was exacerbated by the smaller working space in the retroperitoneum and finding a potential crossing vessel was also more challenging. However according to Kaouk and coauthors, the wristed instrumentation of the da Vinci system helped overcome the limitation of working in a confined space. The outcomes and complications were also similar to that of standard transperitoneal RAP. Cestari et al. published their series of retroperitoneal versus transperitoneal RAP in 36 and 19 patients, respectively [37]. These authors also found similar outcomes in the two groups but noted similar challenges for the retroperitoneal approach, namely, gaining access, limited working space, and the loss of familiar anatomic landmarks. The confined space can also make identification of crossing vessels more difficult as evidenced by a recurrence caused by failure of recognition of one within the retroperitoneal cohort. The authors also noted that antegrade stent placement is more challenging during retroperitoneal RAP [37]. This, however, can be overcome with retrograde placement with flexible cystoscopy without any interruption in the procedure. A recently published randomized comparison of the two approaches performed robotically by a single surgeon (40 patients in each group) showed no significant difference in operative time, hospital stay, success or complication rates [38].

Given the paucity of literature comparing the two approaches, no conclusive statements regarding the superiority of one approach versus the other cannot be made at this time. The choice to pursue the retroperitoneal approach remains largely based upon the surgeon’s preference and experience with the technique and could be considered advantageous in certain situations such as in the presence of extensive intraperitoneal adhesions. The remainder of this chapter will focus on the transperitoneal approach.

LESS Robotic Pyeloplasty

With the emergence of a LP and RAP , laparoendoscopic single-site surgery (LESS) has been of interest in an effort to further minimize surgical invasiveness and potentially recovery. In the pursuit of a “scarless” surgery and given the non-extirpative nature of pyeloplasty surgery, this may represent an ideal setting for a LESS approach as it offers patients improved cosmesis by decreasing the number of ports from 3 to 5 to a single periumbilical incision that is often concealed [39]. Although this approach further raises the level of complexity in performing the procedure, in experienced hands, complication rates are similar to those with other minimally invasive approaches [39]. Early reports with LESS have demonstrated equivalent outcomes compared to conventional LP, with no differences in hospital stay, analgesic requirements, and minor and major complications [40]. LESS can be performed using either laparoscopic or robotic approaches, but some surgeons have found the ergonomic challenges of LESS to be better addressed using the robotic platform. In particular, the wristed instrumentation, surgeon-controlled camera, and ability to electronically reassign the hand controls (“masters”) after crossing the instruments have been cited as particular advantages of robotic LESS. Technical feasibility of LESS in RAP has been demonstrated in a number of case series [41–43] with good short-term outcomes and the authors uniformly highlighting the reduced technical complexity and improved learning curve over LESS LP. A comparison of LESS LP with LESS RAP showed no difference in hospital stay, complications, or outcome except for a longer operative time in the robotic LESS cohort (226 vs. 188 min, p = 0.007) [25]. Despite the initial enthusiasm created with this approach, a lack of universal adoption and recent decline in the performance of LESS surgery was demonstrated in a survey of Endourological Society members [44]. The survey responders highlighted the need for a new robotic platform with modified instrumentation that allows improved suturing ability and reduced robotic arm clashing. The development of the purpose driven da Vinci SP® platform for single-port surgery may specifically circumvent some of these technical challenges to renew interest in LESS RAP and studies assessing this are eagerly awaited.

Robot-Assisted Laparoscopic Pyeloplasty: Equipment List