Laparoendoscopic single-site (LESS) techniques allow for complex surgical procedures to be performed with a small incision and minimal scarring. This approach appears to be ideally suited for procedures that do not require extension of the incision for specimen removal. Early experience has detailed the successful performance of procedures such as pyeloplasty, ureteroneocystostomy and ileal interposition using either conventional or robotic LESS techniques [1,2].
Theoretical advantages of LESS beyond the obvious aesthetic benefits have been proposed and include decreased perioperative pain, faster convalescence and and improved health-related quality of life (HRQL). Because experience with LESS procedures is still quite minimal, few comparisons have been performed between conventional laparoscopic and LESS techniques, with differing results being reported [3–7]. In terms of pyeloplasty, one comparative study has previously been published that did not document any recovery advantages for the LESS approach .
For successful treatment of ureteropelvic junction obstruction (UPJO) with pyeloplasty, several studies have reported equivalent success using laparoscopic techniques compared to open surgery [8–10]. The morbidity of a laparoscopic approach is certainly lower than that for an open incision. How does the LESS approach compare to laparoscopy with regard to perioperative morbidity and the successful treatment of UPJO. The present study compared perioperative factors, success rates and HRQL variables between LESS and conventional laparoscopic pyeloplasty.
PATIENTS AND METHODS
From November 2007 to August 2008, sixteen patients underwent successful LESS pyeloplasty for UPJO diagnosed based on symptomatology, radiographic findings or a combination. One patient was converted to the standard laparoscopic procedure as a result of technical limitations and a failure to progress and is not included in the comparative analysis. Patients undergoing LESS pyeloplasty were compared with sixteen matched patients undergoing standard laparoscopic pyeloplasty identified from our prospectively maintained, institutional review board approved database of laparoscopic pyeloplasty procedures performed subsequent to December 2004. Matching criteria included gender and age (within 10 years), as well as preoperative degree of obstruction (T½ within 15 min) and differential renal function (within 10% ipsilaterally) based on diuretic radionuclide scanning.
All laparoscopic procedures were performed by three surgeons with 12, 6 and 2 years experience, respectively. LESS procedures were performed by the latter two surgeons.
TECHNIQUE FOR STANDARD LAPAROSCOPIC PYELOPLASTY
The procedure begins with cystoscopy and ipsilateral retrograde pyelogram to confirm the diagnosis of UPJO followed by retrograde placement of a 4.7 F × 28 cm JJ ureteral stent. For all patients within the present study, a transperitoneal four-port for a left-sided and five-port (additional port site for liver retraction) for a right-sided approach was used. After mobilization of the colon, the ureter is dissected superiorly until the ureteropelvic junction is identified. Care is taken to preserve lower pole accessory crossing vessels if present and the rind is dissected from the ureteropelvic junction and majority of the renal pelvis. The ureteropelvic junction is then completely dismembered and the ureter spatulated laterally. The ureter and pelvis are transposed anterior to the crossing vessels unless it is considered that this configuration would further obstruct outflow. The anastomosis is then completed with two separate 4–0 braided, synthetic fibre sutures in a running semicircular fashion beginning with the anterior wall. A drain is left in place and removed within 2 days, with subsquent stent removal after 4 weeks.
The technique for LESS pyeloplasty has been described previously . Briefly, cystoscopy and ipsilateral retrograde pyelogram are performed to confirm the diagnosis of UPJO followed by retrograde placement of a 4.7 F × 28 cm JJ ureteral stent. The patient is then placed in modified flank position and a 2-cm incision is used for transumbilical open access and placement of the Triport (Advanced Surgical Concepts, Wickliffe, Ireland) access platform. A combination of standard and articulating laparoscopic instruments is then used to dissect the UPJ. The remainder of the procedure duplicates the standard laparoscopic procedure described above. An additional grasper through a 2-mm access was variably used for dissection in some cases. The 2-mm grasper was used in all cases to aid suturing.
For patients undergoing concomitant ipsilateral pyelolithotomy, a flexible nephroscope was introduced into the renal pelvis via the Triport access platform. A stone basket was then used to grasp and remove all stones. A JJ stent is routinely placed as well as a closed-suction drain. The Foley catheter is generally removed on postoperative day 1 and the drain is removed the next day if drain creatinine levels suggest no extravasation. The stent is removed 4 weeks postoperatively and an initial diuretic radionuclide scan is obtained 2 months later.
A visual analogue pain scale (VAS) was administered by the nursing staff during the hospital stay through discharge. No preoperative VAS scale was administered. A six-question, non-validated, retrospective questionnaire was administered to all patients. (Table 1). Questions 1 and 3 define individual patient convalescence. Question 2 concerns the length of time that narcotic medications were used. Questions 4 to 6 relate to several HRQL variables. The parameters used to determine the success of reconstruction were clinical resolution of symptoms and radiographic success with T½ < 20 min on diuretic radionuclide scanning. Data were analyzed using GraphPad Prism, version 5 (GraphPad Software, Inc., San Diego, CA, USA). Fisher’s exact test was used for categorical variables and the the Wilcoxon rank sum test for continuous variables.
Table 1. Preoperative demographic comparison of standard laparoscopic and LESS pyeloplasty patients
|Number of patients||16||16||–|
|Age (years), mean ± SD||45 ± 15||39 ± 20||0.25|
|BMI (kg/m2), mean ± SD||30 ± 7||23 ± 6||0.002|
|Laterality-right side (%)|| 8 (50%)|| 8 (50%)||1|
|Prior abdominal surgery (%)|| 5 (31%)|| 3 (19%)||0.69|
|Ipsilateral renal stones (%)|| 4 (25%)|| 4 (25%)||1|
Preoperative variables between standard laparoscopic and LESS pyeloplasty groups were not significantly different, except body mass index (BMI; kg/m2) was greater for the standard laparoscopic group (30 ± 7 kg/m2 vs 23 ± 6 kg/m2, P= 0.002) (Table 1). Twelve patients (75.0%) in the LESS group and 11 patients (68.8%) in the laparoscopic group had preoperative abdominal or flank pain (P= 1.00).
All patients in both groups underwent dismembered pyeloplasty and four patients (25%) in each group had concomitant ipsilateral renal stones with intra-operative pyelolithotomy.
No difference was noted for intra-operative estimated blood loss between the two groups (87 ± 38 cc vs 79 ± 43 mL, P= 0.5) (Table 2). Operative time (from skin incision until closure) was longer for the LESS pyeloplasty group, although the difference did not reach statistical significance (215 ± 78 min vs 183 ± 29 min, P= 0.055).
Table 2. Comparison of intra-operative, postoperative and recovery data between standard laparoscopic and LESS pyeloplasty patients
|Approach-transperitoneal, n (%)|| 16 (100%)|| 16 (100%)||1|
|Crossing vessels, n (%)|| 6 (37%)|| 8 (50%)||0.72|
|Dismembered, n (%)|| 16 (100%)|| 16 (100%)||1|
|Estimated blood loss (mL), mean ± SD|| 87 ± 38|| 79 ± 43||0.5|
|Operative time (min), mean ± SD||183 ± 29||215 ± 78||0.055|
|Complications (%)|| 0|| 0||–|
|Length of stay (days), mean ± SD|| 2.4 ± 1.4||2.2 ± 0.4||0.74|
|Morphine equivalents (mg), mean ± SD||49.5 ± 32.7||41.7 ± 48||0.47|
|Complications (%)|| 0|| 0||–|
No difference was noted between the two groups in terms of length of stay or postoperative narcotic analgesic requirements. There was also no difference in VAS pain scores at hospital discharge (LESS: 2.4 ± 2.0 vs 2.6 ± 2.7, P= 0.86). No intra-operative or postoperative complications were noted for either group. All patients in both groups experienced clinical resolution of their symptoms. Comparison of postoperative renal drainage showed no significant difference between the groups (LESS T½: 10.6 min, SD 5.8 vs laparoscopic T½: 12.1 min, SD 7.0; P= 0.60). A patient in the standard laparoscopy group (mean follow-up 17 ± 3 months) and two patients (mean follow-up 13 ± 4 months) in the LESS group had T½ > 20 min (0.063% vs 0.125%, P= 1.00) on diuretic radionuclide scanning. One of the patients in the LESS group with radiographic failure had the appearance of a widely patent ureteropelvic junction on subsequent diagnostic ureteroscopy and therefore endopyelotomy was not performed.
A review of the six-item questionnaire shows equivalent convalescence between the two groups (Table 3). The number of days required for narcotic medication was lower in patients undergoing the LESS technique, with a median (range) of 1 (0–10) days vs 4 (3–14) days (P= 0.10), although this difference did not reach statistical significance. From questions 4 to 6, HRQL parameters were essentially equivalent between the two groups.
Table 3. Comparison of convalescence and quality of life variables between LESS and standard laparoscopic pyeloplasty
|1||21 (7–42)||18 (7–45)||1|
|2|| 4 (3–14)|| 1 (0–10)||0.1|
|3||27 (14–120)||28 (14–60)||1|
|4|| 8.5 (5–10)|| 9 (8–10)||0.9|
|5|| 9.5 (9–10)||10 (all patients)||0.13|
|6||Yes (100%)||Yes (100%)||–|
In each group, four patients underwent concurrent ipsilateral pyelolithotomy with stone-free status documented using either plain abdominal film of kidney, ureter and bladder or CT.
LESS provides aesthetic advantages over standard laparoscopic procedures. The present study suggests that other potential advantages, including decreased analgesic requirements, faster recovery and HRQL benefits, do not exist for LESS compared to standard laparoscopic pyeloplasty. It must emphasized that this is a retrospective review with a short follow-up period and a relatively small study population, which includes our earliest experience with LESS reconstructive procedures. In addition, this series only involves those patients undergoing pyeloplasty and our ability to extrapolate the results and conclusions to other procedures remains unknown.
Although HRQL questions in this study were tailored specifically for this patient population, the questionnaire was not validated. The use of a validated instrument such as the Client Satisfaction Questionnaire-8 or the short form health survey, as well as the determination of any difference in quality adjusted life years between the two approaches, would have been instructive.
Proper patient selection for LESS procedures is still an important factor and may in large part explain the difference in the BMI between the two groups. Performing LESS procedures in obese patients can be challenging because instrumentation for these procedures is still evolving.
Our standard technique for laparoscopic pyeloplasty uses a transperitoneal approach. Therefore, we are unable to compare our LESS procedures with a retroperitoneoscopic approach that may involve fewer ports.
An advantage that standard laparoscopy may have over LESS pyeloplasty is a shorter operative duration, which, in the present study, did not quite reach statistical significance (P= 0.055), although it is probably clinically significant. Matching for BMI may have further punctuated the longer operative times for the LESS procedures. Nevertheless, it must be kept in mind that the surgeons in our group have extensive experience with laparoscopic pyeloplasty, yet this report relates our initial experience with LESS and therefore operative times may continue to decrease with increasing experience.
The initial experience of LESS in urology was single umbilical incision nephrectomy performed in four pigs (eight renal units) and three humans (two non-functioning kidneys and one renal mass) described by Raman et al. . Their study used three standard laparoscopic ports through a single umbilical incision and a 3-mm subxiphoid port was used in the only right-sided nephrectomy for liver retraction. Human procedures were performed with a mean time of 133 min and discharge on hospital day 2 in all cases.
Our group has reported the initial experience with reconstructive urological procedures using LESS . Two single-session, bilateral LESS pyeloplasty procedures (a ureteroneocystostomy with psoas hitch and an ileal interposition) were performed. A 2-mm grasper through a needle puncture was used to assist with suturing. The single umbilical incision was slightly lengthened to perform the bowel reconstruction extracorporeally in the case of ileal ureter. No complications were noted. The addition of a 2-mm port and grasper is still our routine practice for suturing in reconstructive procedures because the precision required for successful repair must be weighed against the morbidity of a minimal entry.
Our group has also reported performance of pyeloplasty and ureteroneocystostomy using the The da Vinci S® robot (Intuitive, Sunnyvale, CA, USA) through a single incision [2,13]. Robotic articulation using EndoWrist® technology may help address the problems of loss of triangulation with LESS. Thus far, the incision required for robotic LESS is slightly larger than that needed for standard LESS reconstructive procedures.
In the recent literature, experience and interest is growing concerning procedures requiring fewer cutaneous incisions. Reports exist of LESS being used for almost the entire spectrum of urological procedures, including renal cryotherapy, cyst decortication, simple nephrectomy, radical nephrectomy, donor nephrectomy, partial nephrectomy, adrenalectomy, ileal interposition, pyeloplasty, ureteroneocystostomy, sacrocolpopexy, varicocelectomy, radical prostatectomy, simple prostatectomy, radical cystectomy, transvesical removal of mesh, robotic partial nephrectomy, robotic radical nephrectomy, robotic simple nephrectomy, robotic radical prostatectomy and robotic pyeloplasty [14–26]. Successful completion of hybrid natural orifice translumenal endoscopic surgery nephrectomy has been reported and the initial pure natural orifice translumenal endoscopic surgery nephrectomy has been performed [27,28].
Amidst all of the excitement surrounding these ever more minimally invasive approaches, the question arises as to whether benefits exist for decreased pain, shorter convalescence and improved HRQL compared to standard laparoscopy. Perhaps, more importantly, equivalent oncological or functional efficacy should be shown for these techniques so that they can be more universally adopted.
Thus far, four groups have compared LESS with standard laparoscopic procedures [3–7]. In the only study comparing pyeloplasty results, 14 patients undergoing LESS pyeloplasty were matched 2 : 1 to a previous cohort of 28 patients who underwent conventional laparoscopic pyeloplasty . Intracorporeal suturing was aided through a 5-mm instrument placed in the eventual drain site. Median operative times and median estimated blood loss were significantly lower in patients undergoing LESS. Nevertheless, the majority of control patients underwent cystoscopy with retrograde stent placement, which requires repositioning of the patient and additional equipment compared to antegrade stent placement performed in all LESS cases. In addition, more patients in the laparoscopic cohort had previous endoscopic management of the disease, which may have made dissection more difficult, contributing to an increased overall operative time. Moreover, the small statistical difference in estimated blood loss was probably not clinically significant. No difference was noted between the two groups with respect to length of stay, morphine equivalents required, and minor or major postoperative complications.
Raman et al.  compared 11 patients undergoing LESS nephrectomy with 22 patients undergoing nephrectomy with standard laparoscopic technique in the first case–control study. According to their study, no difference was noted for any perioperative data, except a small difference in blood loss favouring LESS. Alternatively, Canes et al.  compared a single institution experience of LESS and standard laparoscopic donor nephrectomy. Mean warm ischaemia time was longer in the LESS group (3 vs 6.1 min; P < 0.001), even if allograft function was comparable between the groups at 3 months. Patients undergoing LESS donor nephrectomy had similar in-hospital analgesic requirements and mean VAS scores at discharge. After discharge, their convalescence, as evaluated by using VAS scores and questionnaires containing patient-reported time to recovery end-points, was faster, including days on oral pain medication, days off work and days to full physical recovery.
Raybourn et al.  matched a total of 11 patients undergoing LESS laparoscopic simple nephrectomy with a group of 10 patients who previously underwent simple nephrectomies. The investigators reported no significant difference between the two groups in terms of operative time as well as narcotic analgesia requirements.
Jeong et al.  reported the first study comparing LESS vs laparoscopy in the treatment of a benign adrenal adenoma. Nine patients undergoing LESS adrenalectomy were compared with 17 patients undergoing conventional laparoscopic adrenalectomy. Postoperative pain, as measured by the number of days of i.v. patient controlled anaesthesia use, was the only postoperative parameter significantly improved in the LESS group (0.9 vs 1.9 days, P < 0.047). It was concluded that LESS adrenalectomy for benign adrenal adenoma is comparable to the conventional laparoscopic approach in terms of perioperative parameters but shows more desirable cosmetic outcomes.
An area that has not yet been evaluated is the difference in surgeon comfort and procedural ergonomics between single-site surgery and standard laparoscopy/robotics. Use of instruments such as the Subjective Mental Effort Questionnaire, Local Experienced Discomfort Scale, and the Borg Scale of Perceived Exertion, as well as measurements as simple as heart rate, may help to quantify differences in difficulty for the operator between these techniques.
The present study failed to identify any significant advantages of LESS over standard laparoscopic pyeloplasty beyond subjective aesthetic advantages. Importantly, no difference was identified with respect to the success rates between the two techniques and no significant difference in operative time was noted. Therefore, it appears reasonable to offer patients (especially younger individuals and those with a greater interest in aesthetic results) a LESS approach. It should be emphasized that LESS techniques and their instrumentation are in the earliest stages of development and that re-evaluation with larger cohorts in a prospective manner is required as experience grows. Additionally, it should be emphasized that critical comparative studies such as the present one are necessary as further advancements in LESS and natural orifice translumenal endoscopic surgery occur.