Laparo-endoscopic single-site surgery: preliminary advances in renal surgery
Sashi S. Kommu, Urology, City General Hospital, The University Hospital North Staffordshire, Princes Road, Stoke-on-Trent, Staffordshire ST4 7LN, UK. e-mail: email@example.com
We reviewed the preliminary advances in laparo-endoscopic single-site surgery (LESS) as applied to renal surgery, and analyzed current publications based on animal models and human patients. We searched published reports in major urological meeting abstracts, Embase and Medline (1966 to 25 August 2008), with no language restrictions. Keyword searches included: ‘scarless’, ‘scar free’, ‘single port/trocar/incision’, ‘intraumbilical’, and ‘transumbilical’, ‘natural orifice transluminal endoscopic surgery’ (NOTES), ‘SILS’, ‘OPUS’ and ‘LESS’. The lessons learnt from the studies using the porcine model are that further advances in instrumentation are essential to achieve optimum results, and that testing survival in animals is also necessary to further expand the NOTES and LESS techniques. Further advances in instrument technology together with increasing experience in NOTES and LESS approaches have driven the transition from porcine models to human patients. In the latter, studies show that the techniques are feasible provided that both optimal surgical technical expertise with advanced skills, and optimal instrumentation, are available. The next step towards minimal access/minimally invasive urological surgery is NOTES and LESS. It is inevitable that LESS will be extended to involve more complex and technically demanding procedures such as laparoscopic radical prostatectomy and partial nephrectomy.
laparo-endoscopic single-site surgery
(robotic) natural orifice transluminal endoscopic surgery
single port (access/incision) laparoscopic surgery
one-port umbilical surgery
single-port access (renal cryoablation).
Following the first laparoscopic nephrectomy by Clayman et al. in 1991, the initial purported advantages of minimally invasive urological surgery have been repeatedly confirmed [2,3] and now have become established ‘expectations’. Whereas the laparoscopic approach decreased morbidity directly related to the surgical approach, incisions of 1–3 cm long and three to five ports were still required. Each working port and element carries with it an inherent risk of bleeding, infection, concordant organ damage, hernia formation and decreased cosmetic outcome. The development of technical expertise among some groups and advances in surgical instrumentation allowed the laparoscopist to rethink the ‘laparoscopic approach’ to make minimal access surgery ‘more minimal’. This led to the development of a host of surgical approaches now collectively known as laparo-endoscopic single-site surgery (LESS) and encompasses recent terminology including natural orifice transluminal endoscopic surgery (NOTES), single port (access/incision) laparoscopic surgery (SILS) and one-port umbilical surgery (OPUS). The transition from multiple ports to single-port surgery in urology seems to be following the initial transition to laparoscopic urological surgery from open surgery, in terms of starting with the kidney as the platform. This is mirrored in the current work involving nephrectomy (total, partial and donor), pyeloplasty and radiofrequency ablation.
NOTES, SILS, OPUS AND LESS
NOTES has been described as the next ‘surgical frontier’, with the objective of incision-free abdominal surgery. Using NOTES, the surgeon approaches abdominal surgery through natural orifices (mouth, vagina and rectum) thus obviating external abdominal scars. An alternative to conventional laparoscopy and NOTES is SILS, also known as LESS. This uses articulating or bent instrumentation with specialized multi-lumen ports. Such instrumentation would obviate the need to space trocars for triangulation, allowing for the creation of a small, solitary portal of entry into the abdomen. A specific variant of SILS is OPUS, which is a similar concept although using a transumbilical port. This approach is transperitoneal and potentially affords maximum benefits of cosmesis, with the surgical incision hidden within the umbilicus. While appearing promising, potential drawbacks to NOTES nephrectomy are significant. The surgery is significantly longer than using conventional laparoscopy, specialized equipment is necessary, and it is difficult to learn, with new instrumentation and operative approach. Recent advances in the application of NOTES and LESS are reflected in preliminary studies using animal models. The subsequent development of specialized purpose-built instrumentation, coupled with advances in skills, led to the successful application of this in the human patients (Table 1) [4–10].
Table 1. SILS/LESS/NOTES in porcine models, with robot assistance, and in human patients
|Porcine|| || || || || || |
|5||TV +umbilical||TV + 5-mm single umbilical||210||<30 in 4 casesExsanguination, 1||4 successful1 exsanguination|||
|1||TV + 1 midline||TV* + 5-mm single 12-mm midline||300||Minimal||Successful|||
|6||TG + TVe||TVe 5 mm||–||Minimal||Successful|||
|One pig bilateral Nx||TG and TV||30||Minimal||Successful|| |||
|Robot-assisted|| || || || || || |
|1 Simple Nx||TV and TC, robot-assisted single-port, da Vinci NOTES||Single 12-mm midline trocar|
Two 12-mm standard ports into abdomen via vagina and colon. Robotic ports telescoped into 12-mm ports daVinci docked
|10 Radical Nx||TV + umbilical|
|Robot telescope and first robotic arm placed through one 2-cm umbilical incision, second arm placed through vagina||154||72||Successful|||
|10 pyeloplasties|| || || || || || |
|10 partial Nx|| || || || || || |
|Human patients|| || || || || || |
|4 Renal cryotherapy|
1 wedge kidneybiopsy
1 radical Nx
For transperitoneal approach, port inserted transumbilically
|Uni-X† one port, multichannel cannula, with specially designed curved laparoscopic instrumentation||Kidneys|
|Abdominal sacrocolpopexy||Retroperitoneoscopy – port was inserted at tip of 12th rib|| || || || || |
|Simple Nx||single-port TU|| || || || || |
|1 pyeloplasty||Single umbilicalsingle-port TU||R-port||162||50||Successful|||
|Simple Nx||single-port TU||5-mm 30° telescope and two 5-mm working instruments inserted through port|| || || || |
|4 Live-donor Nx||Single umbilical|
single port TU
|6 SPARC||Single umbilicalsingle-port TU|| || || ||Successful|||
PRELIMINARY STUDIES IN ANIMAL MODELS
Gettman et al. in 2002 reported the feasibility of laparoscopic nephrectomy by the transvaginal route in six pigs. One operation was completed exclusively vaginally and the remaining five had one 5-mm transabdominal trocar for the camera port. The latter five cases had a mean operative time of 210 min; five were completed successfully, but in one there was a vascular injury while attempting to place an Endo-GIA stapler (US Surgical, Norwalk, CT, USA), with subsequent torrential haemorrhage. The mean blood loss was <30 mL in the other pigs. There were no significant complications immediately after surgery. The authors concluded that whereas the procedures were feasible, there were inherent limitations as a result of porcine anatomy, and particularly limitations in instrumentation. For successful completion, and indeed expansion, of these procedures, further advances in instrument design and handling was crucial. This led to the development of several devices attempting to address shortcomings in instrumentation.
Clayman et al., in 2007, used a purpose-built device, the TransPort Multi-Lumen Operating Platform (USGI Medical, San Clemente, CA, USA). This was a flexible tool with four working channels and with locking mechanisms that allowed ‘a rigid multitasking platform’ to permit manipulation with both hands at the same time. This device, aided by an endoscopic needle knife and a tissue grasper, was successfully applied to complete a transvaginal single-port NOTES nephrectomy on a female pig. The renal artery and vein were secured separately with vascular EndoGIA and titanium clips, respectively. The kidney was removed vaginally.
The feasibility of a combined transgastric and transvesical approach for nephrectomy was studied by Lima et al. in six female pigs. They installed a transvesical 5-mm channel into the peritoneal cavity under ureteroscopic guidance and a flexible gastroscope was passed orally into the peritoneal cavity. Four right and two left nephrectomies were completed successfully. The authors concluded that dissection, renal pedicle control and mobilization of kidneys was technically feasible. However, they added that removing the specimens from the body cavity was challenging, as there were no reliable methods for removing the specimen with instruments available at the time of the study.
The quest to perform renal surgery using NOTES led to further innovative instrument designs and the combined use of conventional and purpose-built instruments. Isariyawongse et al. described a pure NOTES nephrectomy by using standard laparoscopic instruments through a modified transvaginal trocar. Transgastric endoscopic visualization allowed the introduction of the transvaginal endoscope through a purpose-built laparoscopic trocar/endoscopic over-tube device. They achieved triangulation by using the transgastric endoscope that was retroflexed as required. Transgastric and transvaginal NOTES accesses were achieved with relative ease. They successfully completed bilateral nephrectomies. The group concluded that whereas pure NOTES nephrectomy was technically feasible in the pig by using standard laparoscopic instruments, there was a paucity of information on the long-term physiological implications and complications associated with the technique.
The recent exponential uptake of robot-assisted urological surgery enticed some groups to assess the feasibility of the da Vinci surgical system (Intuitive Surgical, Sunnyvale, CA, USA) as an adjunctive tool in NOTES and LESS for renal disease in the pig model. In a rapid communication, Box et al. published their preliminary experience with a combined transvaginal and transcolonic, single-port, robot-assisted NOTES nephrectomy in a female farm pig. A single 12-mm trocar was placed in the midline and two 12-mm standard laparoscopic ports were placed into the abdomen via the vagina and the colon. The robotic arms were then placed via the 12-mm ports and the camera was inserted via the midline port. A 12-mm transvaginal port allowed instrumentation for the renal artery and vein to be secured individually with a vascular EndoGIA stapler. They successfully extracted the kidney, complication-free, vaginally, with a total operative time of 150 min and an estimated blood loss of <50 mL.
Haber et al. described their initial experience with robotic NOTES (R-NOTES) using the da Vinci robotic platform. The robotic telescope and the first robotic arm were channelled via a single 2-cm umbilical incision with a second robotic arm being placed vaginally. Thirty R-NOTES (10 pyeloplasties, 10 partial nephrectomies and 10 radical nephrectomies) procedures were completed successfully with no need for additional ports and/or open conversion. The group concluded that the approach was feasible and potentially safe in the pig model. The relative ease of intracorporeal suturing using the da Vinci robot, as opposed to the pure laparoscopic approach, was also cited as a useful tool in supplementing the surgeon when challenged with the inherent difficulties of the NOTES approach. They concluded that further advances in robotic technology geared towards NOTES would allow greater uptake of this route.
The lessons learnt from the studies using the porcine model are that further advances in instrumentation are essential to achieve optimum results and that testing survival is also necessary to further expand the NOTES and LESS techniques. Notably, the groups who undertook these studies have advanced baseline laparoscopic skills and preliminary acquisition of skills among surgeons in the early uptake period of laparoscopy would intuitively present a challenge.
THE LIVE HUMAN CASE
Recent advances in instrument technology, together with increasing experience in NOTES and LESS approaches, have driven the transition from porcine models to human patients. Several experienced groups in laparoscopic urological surgery have published their preliminary experience.
Kaouk et al. presented their initial experience with single-port laparoscopic urological surgery using the Uni-XTM Single Port Access Laparoscopic System (Pnavel Systems, Morganville, NJ, USA), a single-port, multichannel cannula, with specially designed curved laparoscopic instrumentation. They completed single-port laparoscopic surgery in 10 patients, including renal cryotherapy in four, wedge kidney biopsy in one, radical nephrectomy in one, and abdominal sacrocolpopexy in four. The mean operative duration for the all procedures was 2.5. The mean blood loss was 100 mL for the renal procedures and 90 mL for sacrocolpopexy. They concluded that single-port laparoscopic renal cryotherapy, wedge kidney biopsy, radical nephrectomy and abdominal sacrocolpopexy were safe and feasible.
Desai et al. reported their initial experience of organ-ablative and reconstructive renal surgery in human patients. They successfully completed scar-less, single-port, transumbilical nephrectomy and pyeloplasty in humans using the R-Port® (Advanced Surgical Concepts, Bray. Wicklow, Ireland). In both cases, the port was inserted through a transumbilical ‘single’ incision and aided with the use of special articulated instruments supplemented by conventional laparoscopic instruments. Ranéet al. reported their initial clinical urological experience with the R-Port and its application in a single-port access (SPA) procedure and OPUS. Two simple nephrectomies for end-stage kidney disease were completed successfully. In all cases, a 5-mm 30° telescope and two 5-mm working instruments were inserted through the port. The tear-resistant thermoplastic elastomer valve allowed each instrument to be operated using an independent fulcrum. Haemostasis and pedicle control was achieved using the Harmonic ScalpelTM (Ethicon, OH, USA) and Hem-o-lokTM (Weck Closure Systems, NC, USA) clips; a novel multi-instrument port cap (TriportTM, Advanced Surgical Concepts) allowed the safe introduction of a 10-mm clip applier. Gill et al. expanded the technique with the successful completion of single-port transumbilical live donor nephrectomy in four patients. This team proposed the umbilicus as an embryonic (E) natural orifice and coined the term E-NOTES. Like Ranéet al., they used the R-Port; pneumoperitoneum was achieved using a 2-mm Veress needle port inserted via a skin needle puncture. This was used to insert a needlescopic grasper to aid tissue handling. The donor kidney was pre-entrapped and extracted transumbilically. They reported that all cases were completed successfully and complication-free, with satisfactory cosmesis.
Recently SPA has been used for renal cryoablation; Goel and Kaouk  reported their initial experience of SPA renal cryoablation (SPARC). A novel multichannel single port was positioned in the umbilicus during the transperitoneal approach and at the tip of the 12th rib during the retroperitoneal approach. Intraoperative ultrasonography was used to locate and observe the renal mass during cryoablation. All six cases in their series, four retroperitoneal and two transperitoneal, had SPARC with no conversion to laparoscopy or open surgery. They concluded that SPARC was feasible and safe for small renal masses.
The results of these studies show that the technique is feasible provided that both optimum surgical technical expertise with advanced skills, and optimal instrumentation, are available.
NOTES and LESS are the next step towards minimal access, minimally invasive urological surgery. Future exponential uptake of NOTES and LESS in urology, and the quest for optimum instruments coupled with the high levels of skill among experienced surgeons in high-volume units, will drive minimal-access scar-less surgery to the next level. In the near future it is anticipated that these techniques will be supplemented with novel approaches, e.g. magnetic anchoring and guidance systems, to enhance current control of camera and instruments. It is inevitable that LESS will be extended to involve more complex and technically demanding procedures, such as laparoscopic radical prostatectomy and partial nephrectomy.
CONFLICT OF INTEREST