Journal of the Formosan Medical Association (2015) 114, 698e703

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ORIGINAL ARTICLE

Ergonomic principles and techniques infacilitating advanced laparoendoscopicsingle site (LESS) urinary tractreconstruction with conventionallaparoscopic instruments

Yao-Chou Tsai a,b,c,*, Chen-Hsun Ho d, Victor Chia-Hsiang Lin e,Fu-Shan Jaw a

a Institute of Biomedical Engineering, National Taiwan University, Taipei, TaiwanbDivision of Urology, Department of Surgery, Taipei Tzu Chi Hospital, Buddhist Tzu Chi MedicalFoundation, Taipei, TaiwancDepartment of Urology, Tzu Chi University, Medical College, Hualien, TaiwandDepartment of Urology, National Taiwan University Hospital, Taipei, TaiwaneDepartment of Urology, E-Da Hospital, Kaoshiung, Taiwan

Received 27 March 2013; received in revised form 23 May 2013; accepted 4 June 2013

KEYWORDSlaparoendoscopicsingle site (LESS)surgery;

laparoscopy;suture technique

Conflicts of interest: The authors* Corresponding author. Division of U

Xindian, Taipei, Taiwan.E-mail address: tsai1970523@yaho

0929-6646/$ - see front matter Copyrhttp://dx.doi.org/10.1016/j.jfma.201

Background/Purpose: The technical and ergonomic details of laparoendoscopic single site(LESS) reconstruction have not been reported. In this study, we explored the feasibility andsafety of performing advanced LESS upper urinary tract reconstruction with conventional lapa-roscopic instruments.Methods: Between September 2010 and March 2011, we retrospectively reviewed prospec-tively collected data from five patients who underwent LESS urinary tract reconstruction.The LESS reconstruction included pyeloureterostomy (N Z 1), dismembered pyeloplasty(N Z 2), ureteroneocystostomy (N Z 1), and ureteroplasty for bifid blind ending ureter(N Z 1). The perioperative and postoperative parameters were collected for analysis. The er-gonomic principles and techniques are detailed.Results: All reconstructive LESS procedures were completed successfully without open conver-sion or laparoscopic conversion. Ancillary ports or ancillary instruments were not applied in

have no conflicts of interest relevant to this article.rology, Department of Surgery, Buddhist Tzu Chi General Hospital, Taipei Branch, 289 Jianguo Road,

o.com.tw (Y.-C. Tsai).

ight ª 2013, Elsevier Taiwan LLC & Formosan Medical Association. All rights reserved.3.06.002

Ergonomic principle of robotic LESS 699

any of the patients. The mean patient age was 40.4 years. The mean operative time was213 � 69 minutes, the estimated blood loss ranged from minimal to 50 mL, and the mean hos-pital stay was 4.4 � 4 days. No operation-related complication occurred.Conclusion: Based on our ergonomic principles and suturing/knotting techniques, conventionallaparoscopic instruments are feasible and safe for LESS urinary reconstructive procedures.Copyright ª 2013, Elsevier Taiwan LLC & Formosan Medical Association. All rights reserved.

Figure 1 The configuration of mini-triangulationdwith theendoscope at the top and the instruments at top-left and top-right of the triangledis maintained during the whole course ofsuturing and knotting.

Introduction

The safety and feasibility of laparoendoscopic single site(LESS) surgery has been approved for various urologicaloperations.1e6 In experienced hands, LESS surgery can besuccessfully performed for most indications, and it hascomparable short-term outcomes as conventional laparos-copy. The clinical advantages of LESS surgery over conven-tional laparoscopy is still under debate; however, the initialrandomized control trials regarding LESS surgery revealinspiring convalescent advantages, in addition to appealingcosmetic results.1,7e9 This novel technique theoreticallyreduces multiple trocar-related parietal trauma and thepossibility of multiple trocar-related complications.

However, the LESS approach is hampered by its originaldesign: a single skin entry, parallel and extremely closeinstrument arrangements, and a very limited instrumenttriangulation, which is an essential part of laparoscopy su-turing. The common solutions for intracorporeal suturing inLESS surgery are incorporating an accessory 2-mm port, andarticulating needle holders, or prebent laparoscopic in-struments. The drawbacks are extra skin incisions, crossingmanipulation, and using nondurable, expensive commercialinstruments.2,10e16 To date, the technical and ergonomicdetails have not been reported. We report in this paper ourtechnical principles and techniques in facilitating pure LESSintracorporeal suturing and knot tying with conventionallaparoscopic instruments, and we report our early results invarious advanced LESS urinary tract reconstructionprocedures.

Materials and methods

Ergonomic principles

The advantages of triangulation in laparoscopic surgery arethe enhancement of a surgeon’s spatial perception, ergo-nomic feasibility, decreased instrument fighting, and thusimproved procedure efficiency. In LESS surgery, when allthe instruments have to point to the same target (i.e, notcrossing each other), instrument triangulation is nearlylost. An angle-viewed or flexible laparoscope is a commonsolution because the angle-viewed scope can be positionedin a different direction from the target and thus can crosswith instruments so that the working instruments regainroom for manipulation during LESS surgery.

Intracorporeal suturing and knotting

Laparoscopic suturing and knotting is a crucial part of uri-nary tract reconstruction. Because of the parallel

arrangement of instruments and instrument clashing,reconstruction is challenging when using articulating in-struments and even more challenging when using conven-tional instruments during LESS surgery. Based on ourexperience, instrument triangulation is an essential part ofLESS suturing and knotting, although triangulation is verylimited. Thus, maintaining mini-triangulation with theendoscope at the top of the triangle and the other in-struments at the top left and top right of the triangle is theprinciple of reconstruction with conventional instruments(Fig. 1). Because of the parallel arrangement of the workinginstruments, the needle could be easily loaded perpendic-ularly in the needle holder, which is ready for suturing(Fig. 2). The spatial limitation and the fixed single skinincision inevitably limits the freedom of suturing. To placesutures at a right angle to the line of anastomosis, the di-rection of anastomosis line should be adjusted with theassistant instrument or with a stay suture.

Figure 2 The needle is easily loaded perpendicularly in the needle holder because the two instruments are parallel.

700 Y.-C. Tsai et al.

For efficient knotting, the length of the suture threadshould be 15 cm or longer. Two long-curved or right-angledjaw dissecting forceps are especially useful for makingloops under the parallel arrangement of the instruments.After the needle passes through the tissue, the end of thethread without the needle should be shorter than theopposite thread, and grasped with the contralateral forcepto make loops for knotting (Fig. 3). The end of the threadis then grasped with the other forcep and the knot issecured by pulling the two instruments in opposite di-rections (Fig. 4). The configuration of triangulation should

Figure 3 The thread distal (i.e., short thread) to the needle shomake loops for knotting, the long thread is grasped with the force

be carefully maintained during the whole course ofknotting.

Patients and procedures

Between September 2010 and March 2011, we retrospec-tively reviewed prospectively collected data from five pa-tients who underwent LESS urinary tract reconstructionperformed by a single surgeon. The LESS reconstructionprocedures included pyeloureterostomy (N Z 1), dismem-bered pyeloplasty (N Z 2), ureteroneocystostomy (N Z 1),

uld remain shorter than the thread proximal to the needle. Tops that is contralateral to the needle.

Figure 4 The distal end of the thread is grasped by the otherforceps and the knot is secured by pulling the two instrumentsin opposite directions.

Ergonomic principle of robotic LESS 701

and ureteroplasty for bifid blind ending ureter (N Z 1).Table 1 lists the detailed surgical indications and pro-cedures. The perioperative and postoperative parameterswere collected for analysis.

All procedures were performed by a homemade singleaccess platformdusing an Alexis wound retractor (AppliedMedical, Rancho Santa Margarita, CA, USA)dwhich hasbeen described previously.17 After the skin incision, awound retractor was inserted. Double-layered sterile sur-gical gloves were then snapped onto the retractor with theupper finger parts truncated. The trocars were insertedthrough the glove and secured by ligatures. For all pro-cedures, a 2-cm periumbilical incision was created and anextra-small Alexis wound retractor was used for primary

Table 1 Demographic data and surgical indications for the LES

Procedure No. ofpatients

Age(y)

Sex BMI(kg/cm2)

Pyeloureterostomy 1 25 F 19.1Dismembered pyeloplasty 2 35 and

44F/M 22.8 and

26.7Ureteroneocystostomy 1 59 F 24Ureteroplasty 1 39 F 26.9

APN Z acute pyelonephritis; BMI Z body mass index; LESS Z laparo

access. Sutures (4-0 Monocryl) (Applied Medical, RanchoSanta Margarita, CA) required for reconstruction weredelivered into the peritoneal cavity by penetrating thegloves on the homemade port and vice versa.3 A ureteralstent was placed in an antegrade fashion in all patients.Table 2 lists the detailed laparoscopic instruments andconsumables. All instruments were conventional straightlaparoscopic instruments, except an extended length 5-mmlaparoscope. The curved needle was introduced into theabdominal cavity through the glove part of the homemadesingle port. For the double-layered design, air leakage wasnot significant after needle puncturing. The perioperativeand postoperative data were recorded and analyzed. Thedrainage status of the reconstructed upper tracts wasconfirmed by intravenous pyelography or computed to-mography (CT) scan.

Results

All LESS urinary tract reconstruction procedures werecompleted successfully without open conversion or lapa-roscopic conversion. Ancillary ports or ancillary instrumentswere not applied in all patients. Table 1 lists the de-mographic data. For the entire cohort, the mean patientage was 40.4 years (range, 25e59 years), mean body massindex was 23.9 kg/m2 (range 19.1e26.9 kg/m2). Theinstallation of homemade single ports was successful in allpatients. For the unique double-layered design, significantair leakage was not encountered after needle penetrationor after prolonged surgery.

The mean operative time was 213 � 69 minutes, theestimated blood loss ranged from minimal to 50 mL, and themean hospital stay was 4.4 � 4 days. There were nointraoperative or postoperative complications. The medianfollow-up period was 5.5 months (range, 3.75e7.5 months).For ureteropelvic junction obstruction, an anterior crossingvessel was indentified in a 35-year-old female. Improve-ment of hydronephrosis was identified in all patients byintravenous urography, serial renal ultrasonography, or CTscan.

Discussion

Laparoendoscopic single site surgery is a novel technique,modified from conventional laparoscopy, in which thewhole procedure is performed via a single skin incision.Therefore, it follows the same surgical principles of con-ventional laparoscopy. The only difference is that the

S procedures.

Indication or diagnosis

Complete duplicated ectopic ureter with hydronephrosisUreteropelvic junction obstruction (crossing vessel in1 patient and high insertion in 1 patient)Distal ureteral stricture because of previous hysterectomyBifid blind ending ureter with recurrent APN

endoscopic single-site.

Table 2 The detailed laparoscopic instruments and consumables used in the LESS procedure.

Instruments Diameter(mm)

Length (cm) Additional expenses in comparisonto conventional LPS (US dollars)

30� endoscope 5 29 ReusableDissecting forceps 5 36 ReusableGrasping forceps 5 36 ReusableScissors 5 36 ReusableDissecting electrode 5 36 ReusableNeedle holder 5 33 ReusableSuction and irrigation cannula 5 36 ReusableAlexis wound retractor XSml N.A. 785 mm trocars 5 N.A. No greater expense than

conventional laparoscopy

LESS Z laparoendoscopic single-site; LPS Z laparoscopy; N.A. Z not applicable; XSml = extra small.

702 Y.-C. Tsai et al.

nature of a single incision precludes the ergonomic princi-ple of laparoscopic triangulation. Therefore, the in-linesuturing by using a conventional laparoscopic needle holderpresents an extreme challenge for LESS reconstructiveprocedures.11 Commercial articulating needle holders(Cambridge Endoscopic devices (Framingham, MA); NovareSurgical Systems (Cupertino, Calif)) offer a solution for theLESS reconstruction procedure.3 An ancillary 2-mm or 3-mmneedle port can otherwise offer a primary solution for LESSreconstructive procedures. The drawbacks of the afore-mentioned solutions are the inherent learning curvebecause of the counter-intuitive manipulation of crossingmanipulation and additional parietal trauma due to theancillary instrument. Performing LESS reconstructive pro-cedure with conventional straight instruments seems to bea more reasonable and intuitive way, and conventional fa-cilities are always ready for use worldwide. However, thetechnique has never been detailed anywhere in the medicalliterature.

According to our previously described ergonomic andgeometric principles, most upper urinary tract reconstruc-tion could be successfully completed in pre-existing facil-ities and with conventional laparoscopic instrumentswithout an ancillary port or surgical conversion. No patienthad postoperative complications. The operating time waslonger than that of conventional laparoscopic reconstruc-tion procedures reported in the medical literature, but theincreased time may be related to the time needed to createthe custom-make single port or related to inferior proce-dure efficiency because of the extremely limited triangu-lation. Based on our experience, conventional laparoscopicinstruments could be safely and successfully used in LESSurinary tract reconstructions.

Prior to initiating the LESS procedure, several challengesshould be addressed such as the loss of instrument trian-gulation and the crowding of instruments. Various com-mercial articulating instruments offer solutions to theaforementioned problems. However, crossing manipulationof these articulating instruments is counter-intuitive andtherefore results in another learning curve that needs to beovercome.2 Based on our ergonomic principles, LESS sur-gery could be performed safely with reasonable efficiency,although the operative time of LESS surgery is a little longerthan that of conventional laparoscopy.

Several techniques may help improve the procedure’sefficiency. First, because of the restraint of instrumentangles, the surgeon can tent up the tissues or vessels to bedissected by taking the grasper to hold and pull durabletissues some distance away from the exact range of in-terest. Other instruments can then be used to completethe dissection, to control vessels, or to transect tissues/vessels. Second, the assistant holding the telescope needsto move the camera focus to the tissues that thenondominant hand grasper is going to hold. Let it grasp thetissue in position. The assistant then swiftly shifts thescope back to the exact range of interest for the dominant-hand instrument to execute its planned dissection. Third,to avoid unnecessary damage to the tissues, especiallywhen the tissue is not under the direct visualization of themonitor screen, the assistant instruments responsible fortissue holding cannot be moved too vigorously. Fourth, it isvery important to maintain instrument triangulation forsuccessful intracorporeal suturing and knotting. The rangeof movement is extremely limited under such circum-stances, however, intracorporeal suturing and knotting arefeasible.

The only drawback of the LESS surgery is the proceduralefficiency is not as good as that of conventional laparoscopywith normal triangulation.

The LESS reconstructive technique represents an idealprocedure for its minimal and nearly invisible scarbecause specimen retrieval is not necessary. However,reconstructive LESS surgery is still in its early stages oftechnique and technology development. The recon-structive LESS surgery is a complicated and extremelydifficult procedure even for surgeons who are experi-enced in conventional laparoscopic reconstructive orLESS procedures. An early series indicated that recon-structive LESS surgery may be associated with a highercomplication rate.18 Therefore, we only recommend ourtechnique to surgeons who are experienced inconventional laparoscopic reconstructive procedures. Inconclusion, based on our ergonomic principles and su-turing/knotting techniques, conventional laparoscopicinstrument is feasible and safe for LESS urinary recon-structive procedures. The outcome advantages ofreconstructive LESS surgery are still under investigation;however, in experienced hands, reconstructive LESS

Ergonomic principle of robotic LESS 703

surgery could be successfully performed for most in-dications with acceptable clinical outcomes.

References

1. Kurien A, Rajapurkar S, Sinha L, Misshra S, Ganpule A,Muthu V, et al. First prize: standard laparoscopic donor ne-phrectomy versus laparoendoscopic single-site donor ne-phrectomy: a randomized comparative study. J Endourol2011;25:365e70.

2. Khanna R, Stein RJ, White MA, Isac W, Laydner H, Autorino R,et al. Single institution experience with robotic laparoendo-scopic single site renal procedures. J Endourol 2012;26:230e4.

3. Tsai Y-C. Feasibility and safety of conventional laparoscopicinstruments in laparoendoscopic single-site surgery: experi-ence with one hundred cases. Formosan J Surg 2011;44:215e20.

4. Tai HC, Ho CH, Tsai YC. Laparoendoscopic single-site surgery:adult hernia mesh repair with homemade single port. SurgLaparosc Endosc Percutan Tech 2011;21:42e5.

5. Chung SD, Huang CY, Wang SM, Tai HC, Tsai YC, Chueh SC.Laparoendoscopic single-site (LESS) retroperitoneal adrenal-ectomy using a homemade single-access platform and standardlaparoscopic instruments. Surg Endosc 2011;25:1251e6.

6. Chung SD, Huang CY, Wang SM, Chueh SC, Hung SF, Tsai YC,et al. Laparoendoscopic single-site (LESS) nephroureterectomyand en bloc resection of bladder cuff with a novel extravesicalendoloop technique. Surg Innov 2010;17:361e5.

7. Fagotti A, Bottoni C, Vizzielli G, Alletti SG, Scambia G,Marana E, et al. Postoperative pain after conventional lapa-roscopy and laparoendoscopic single site surgery (LESS) forbenign adnexal disease: a randomized trial. Fertil Steril 2011;96:255e9. e2.

8. Tugcu V, Ilbey YO, Mutlu B, Tasci AI. Laparoendoscopic single-site surgery versus standard laparoscopic simple nephrectomy:a prospective randomized study. J Endourol 2010;24:1315e20.

9. Zheng M, Qin M, Zhao H. Laparoendoscopic single-site chole-cystectomy: a randomized controlled study. Minim InvasiveTher Allied Technol 2012;21:113e7.

10. Bi Y, Lu L, Ruan S. Using conventional 3- and 5-mm straightinstruments in laparoendoscopic single-site pyeloplasty inchildren. J Laparoendosc Adv Surg Tech A 2010;21:969e72.

11. Clements T, Raman JD. Laparoendoscopic single-site pyelo-plasty. Ther Adv Urol 2011;3:141e9.

12. Gupta NP. Laparoendoscopic single-site pyeloplasty: a com-parison with the standard laparoscopic technique. BJU Int2011;107:816.

13. Ju SH, Lee DG, Lee JH, Baek MK, Jeong BC, Jeon SS, et al.Laparoendoscopic single-site pyeloplasty using additional2 mm instruments: a comparison with conventional laparo-scopic pyeloplasty. Korean J Urol 2011;52:616e21.

14. Tracy CR, Raman JD, Bagrodia A, Cadeddu JA. Perioperativeoutcomes in patients undergoing conventional laparoscopicversus laparoendoscopic single-site pyeloplasty. Urology 2009;74:1029e34.

15. Tugcu V, Ilbey YO, Polat H, Tasci AI. Early experience withlaparoendoscopic single-site pyeloplasty in children. J PediatrUrol 2011;7:187e91.

16. Zhou H, Sun N, Zhang X, Xie H, Ma L, Shen Z, et al. Tran-sumbilical laparoendoscopic single-site pyeloplasty in infantsand children: initial experience and short-term outcome.Pediatr Surg Int 2012;28:321e5.

17. Tai HC, Lin CD, Wu CC, Tsai YC, Yang SS. Homemade tran-sumbilical port: an alternative access for laparoendoscopicsingle-site surgery (LESS). Surg Endosc 2010;24:705e8.

18. Best SL, Donnally C, Mir SA, Tracy CR, Raman JD, Cadeddu JA.Complications during the initial experience with laparoendo-scopic single-site pyeloplasty. BJU Int 2011;108:1326e9.