|Year : 2016 | Volume
| Issue : 2 | Page : 102-108
Single-centre experience of retroperitoneoscopic approach in urology with tips to overcome the steep learning curve
Aneesh Srivastava, Sanjoy Kumar Sureka, Saurabh Vashishtha, Shikhar Agarwal, Md Saleh Ansari, Manoj Kumar
Department of Urology and Renal Transplantation, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, Uttar Pradesh, India
|Date of Submission||28-Nov-2014|
|Date of Acceptance||12-May-2015|
|Date of Web Publication||11-Mar-2016|
Department of Urology and Renal Transplantation, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, Uttar Pradesh
Source of Support: None, Conflict of Interest: None
Context: The retroperitoneoscopic or retroperitoneal (RP) surgical approach has not become as popular as the transperitoneal (TP) one due to the steeper learning curve. Aims: Our single-institution experience focuses on the feasibility, advantages and complications of retroperitoneoscopic surgeries (RS) performed over the past 10 years. Tips and tricks have been discussed to overcome the steep learning curve and these are emphasised. Settings and Design: This study made a retrospective analysis of computerised hospital data of patients who underwent RP urological procedures from 2003 to 2013 at a tertiary care centre. Patients and Methods: Between 2003 and 2013, 314 cases of RS were performed for various urological procedures. We analysed the operative time, peri-operative complications, time to return of bowel sound, length of hospital stay, and advantages and difficulties involved. Post-operative complications were stratified into five grades using modified Clavien classification (MCC). Results: RS were successfully completed in 95.5% of patients, with 4% of the procedures electively performed by the combined approach (both RP and TP); 3.2% required open conversion and 1.3% were converted to the TP approach. The most common cause for conversion was bleeding. Mean hospital stay was 3.2 ± 1.2 days and the mean time for returning of bowel sounds was 16.5 ± 5.4 h. Of the patients, 1.4% required peri-operative blood transfusion. A total of 16 patients (5%) had post-operative complications and the majority were grades I and II as per MCC. The rates of intra-operative and post-operative complications depended on the difficulty of the procedure, but the complications diminished over the years with the increasing experience of surgeons. Conclusion: Retroperitoneoscopy has proven an excellent approach, with certain advantages. The tips and tricks that have been provided and emphasised should definitely help to minimise the steep learning curve.
Keywords: Laparoscopy, retroperitoneoscopy, tips and tricks
|How to cite this article:|
Srivastava A, Sureka SK, Vashishtha S, Agarwal S, Ansari M, Kumar M. Single-centre experience of retroperitoneoscopic approach in urology with tips to overcome the steep learning curve. J Min Access Surg 2016;12:102-8
|How to cite this URL:|
Srivastava A, Sureka SK, Vashishtha S, Agarwal S, Ansari M, Kumar M. Single-centre experience of retroperitoneoscopic approach in urology with tips to overcome the steep learning curve. J Min Access Surg [serial online] 2016 [cited 2020 Apr 5];12:102-8. Available from: http://www.journalofmas.com/text.asp?2016/12/2/102/178517
| ¤ Introduction|| |
Laparoscopy has been established as the standard approach for many urological procedures. The early applications of laparoscopy were largely limited to diagnostic purposes. The historical landmark step forwards was the transperitoneal (TP) laparoscopic nephrectomy by Clayman et al. in 1990. Retroperitoneal (RP) minimally invasive surgery was first attempted by Wittmoser  in 1973 for lumbar sympathectomy with the help of a telescope and pneumatic dissection with carbon dioxide. In the field of urology, the first retroperitoneoscopic surgery (RS) for ureteral stone was performed by Wickhamin  in 1979 but the wide role of retroperitoneoscopy was realised only after 1993 once RP dissection was performed using a balloon by Gaur. Later on, Gill et al. highlighted further prospects of the RP approach in the urological armamentarium. However, it could not gain much popularity due to the steeper associated learning curve compared to the TP approach. The review of the existing literature revealed a limited number of studies predominantly highlighting the feasibility, safety and efficacy of the procedure for various upper tract diseases. However, there is a complete dearth of knowledge regarding the nuances of the procedure in different situations. Furthermore, there is the issue of the steeper learning curve. Therefore our single-institution experience focuses on the feasibility, advantages and complications of RS performed over the past 10 years. We also highlight certain tips and tricks useful to perform successful RS, which would definitely help minimise the steep learning curve for younger urologists.
| ¤ Patients and Methods|| |
This study was a retrospective analysis of computerised hospital data for patients who underwent retroperitoneoscopic urological surgery done by a mentor surgeon (who initiated and standardised the techniques at this centre) and two other surgeons trained under the mentorship of the first surgeon, at a tertiary care centre.
Between 2003 and 2013, 314 cases of retroperitoneoscopic procedures were performed for various urological diseases. These included 143 cases of simple nephrectomy for non-functional or poorly functional kidney, 54 cases of donor nephrectomy, 49 cases of laparoscopic ureterolithotomy or pyelolithtomy for urolithiasis, 21 cases of radical nephrectomy for renal tumour, 13 cases of adrenalectomy for benign tumour, 9 cases of pyelolymphatic dissection for intractable chyluria, 18 cases of cyst deroofing for symptomatic simple renal cyst, and 2 cases of pyeloplasty for pelvi-ureteric junction obstruction. The mean follow-up in our study was at 16.5 ± 4 months.
The indications and demographic characteristics of the patients have been summarised in [Table 1].
We have analysed the operative time, peri-operative complications, time for return of bowel sound, hospital stay, advantages, and difficulties involved and the variations in techniques to circumvent them. Post-operative complications were stratified into five grades using the modified Clavien classification system (MCC) [Table 2].
Statistical data were presented as mean, median or percentile, as indicated, and Microsoft Excel 2007 (Microsoft Windows, Washington, USA) was used for data compiling and analysis.
Patient position and port placement
Following general anaesthesia, each patient was placed in standard full flank or lateral decubitus position (ipsilateral side facing upwards). An axillary roll was placed to protect the dependent brachial plexus. The operating table was flexed, with the elevation of a kidney rest, to widen the space between the iliac crest and the costal margin. The patient's back was positioned flush to the side operating table where the surgeon and assistant stood. Care was taken to secure the patient to the table using cloth or tape and to ensure that all pressure points were padded adequately.
The anatomic access site for RS was the space between the 12th rib superiorly, the iliac crest inferiorly, the lateral border of the paraspinal muscles postero-laterally, and the lateral peritoneal reflection antero-medially.
Surgical access to the retroperitoneum began with a 1-cm transverse incision just anterior and inferior to the tip of the 12th rib on the lateral border of the paraspinal muscles. The flank muscles were incised until the thoraco-lumbar fascial layer could be appreciated, and the latter was pierced using a straight Kocher clamp to reach the RP space. Here we realised that using the index finger-guided Kocher sclamp for the gentle and controlled perforation of the deep fascia was an especially suitable method substituting the use of a cautery or scalpel in an obese patient. Subsequently the little or index finger was inserted for better tactile perception of the psoas muscle posteriorly, the peritoneum anteriorly and the lower pole of kidney superiorly. Though there is no scientific basis for it, in our experience this technique was still very useful. A tunnel was created with an index finger to push the peritoneum forward, thus creating a RP space.
Now the balloon dilator OMS-PBD 1000 balloon dilator (Covidien Medtronic, Minneapolis, USA) was introduced and in this step, too, we found that the use of lubricant gel may help to smooth entry and proper placement of the balloon to prevent disruption of the medially located peritoneum. The balloon was then inflated with 200 cc of air and initial scopy was done to confirm the correct position of the balloon. The balloon was further inflated to 500-600 cc of air to create RP space, pushing the kidney and the peritoneum anteriorly. The dilator was removed and replaced with a Hasson cannula with a blunt-tipped trocar (Tyco Healthcare; United States Surgical, manufactured by Covidien). This port was used as the camera port. We routinely used 30° optics in all cases. Pneumoperitoneum was created and a pressure of 12-15 mmHg was maintained.
On the left side a second port of 10 mm size was placed at the renal angle just lateral to the paraspinal muscles under vision. A third port of 5 mm was placed on the mid-axillary line just above the level of the iliac crest. An additional port of 10 mm size was placed on the anterior axillary line just below the costal margin for retraction [Figure 1]. On the right side the posterior port at the renal angle was of 5 mm and both the anterior ports were of 10 mm size [Figure 2].
Our modifications in various procedures
Pre-operative stent placement in pyelolithotomy makes the procedure easier. In case of a large pelvic stone, it can be broken into pieces with the help of a lithoclast [Figure 3], and stone fragments are removed after placing them in a glove finger.
|Figure 3: Introduction of spinal needle for confirmation of correct port site before anterior port placement|
Click here to view
While doing simple nephrectomy, in cases of adhesions and the inability to proceed in the extracapsular plane the dissection should be carried out in the sub-capsular plane starting from the upper pole to prevent inadvertent injury to the adrenal gland. The presence of lymph nodes, short and stout renal vein, fragile parasitic vessels and the inferior vena cava act as an anatomical barrier that may complicate right TP radical nephrectomy in a large tumour.
During radical nephrectomy for T2 disease (size >7 cm) the TP approach has a high conversion rate because of the short and stout renal vein, fragile parasitic vessels, and the inferior vena cava, which often act as an anatomical barrier for arterial dissection. However, it may be difficult to complete the whole dissection using the RP approach because of the large size. Thus a combined RP-and-TP approach is preferred. First the renal artery is controlled with the conventional RP approach as described, as it allows direct and quick access to the hilum, allowing early control of the renal artery, and then the TP route is used for clipping of the renal vein and removal of the specimen. For the RP approach the operating surgeon stands on the right side of the table with the patient on the right edge of the table (in lateral decubitus position with the right side facing up). For the TP approach the patient is shifted to the left edge of the table with the operating surgeon on the left side. For TP approach, similar to conventional transperitoneal nephrectomy, three additional ports are required.
In pyelo-lymphatic disconnection, it is very important to differentiate the dilated lymphatic channels from small vascular branches. For confirmation, traction is released and papaverine may be used to alleviate the arterial spasms. It is imperative to be very sure before clipping and division.
There was a significant advantage in cystopericystectomy of a hydatid cyst retroperitoneoscopically. The close cavity of retroperitoneum prevents contamination of the peritoneal cavity in cases of accidental spillage of active cyst.
During the deroofing of a simple renal cyst, proper cyst wall identification is important to avoid injury to renal parenchyma by initial aspiration using the needle.
Retroperitoneoscopic adrenalectomy could be technically challenging. The excess overhanging fat must be excised initially only to increase working space. The instruments in the anterior ports should be swapped so that the superior anterior port becomes the primary port for using the dissection instruments, and the inferior anterior port should be used for retraction. Dissection should be carried out at the upper pole of the kidney, to attempt to dissect the kidney away from the tumour rather than dissecting the tumour away from kidney.
| ¤ Results|| |
RS was successfully completed in 95.5% (300) patients, including 4% procedures which were electively performed by combined approach (both RP and TP); 3.2% (10) required open conversion and 1.4% (4) procedures were converted to the TP approach. Most common reason for conversion was bleeding in eight patients. Their mean age was 46 ± 9.5 years (range: 16-71 years), and 41 (13%) of the patients had prior history of abdominal surgery. Mean blood loss was 148 ± 54 mL (range: 50-900 mL); the mean operating time was 141 ± 26 min (range: 90-300 min) Mean hospital stay was 3.2 ± 1.2 days and the mean time for returning of bowel sounds was 16.5 ± 5.4 h. Eleven (11) patients (3.5%) required intra-operative blood transfusion. A total of 16 patients (5%) had post-operative complications and a majority (12 patients, 75%) were grade I and II as per MCC [Table 3] and [Table 4]. Only 4 patients had grade III complications, which included bowel injury in 2 patients (managed with laparotomy and primary repair) and urinoma in 2 patients, which required percutaneous drainage or stenting. These major intra-operative and post-operative complication rates depended on the difficulty of the procedure but the difficulty diminished over the years with the increasing experience of the surgeons.
| ¤ Discussion|| |
In urological laparoscopic procedures, the TP approach has been conventionally preferred because it is easier to perform and allows the surgeon to work in wider and more familiar surroundings. Retroperitoneoscopy is an alternative approach to performing renal and ureteric procedures. This approach has certain unique advantages over the TP approach.,, The main advantage is the direct approach to the retroperitoneum despite the technical hitches associated with the smaller operating chamber. RP organs and certain landmarks can be visualised directly. By avoiding the peritoneal cavity the risk of inadvertent visceral and vascular injury may be reduced. Intestinal retraction is much easier as the peritoneal envelope surrounds the intestines and individual bowel loops need not be retracted. Post-operative adhesions and peritonitis, if there is spillage of infected renal contents, can be completely avoided. It is also worth mentioning that post-operative recovery is early and smooth following RS and that the incidence of incisional hernia is very rare. In the early phase of our experience of retroperitoneoscopy, we also faced certain difficulties which have later been circumvented by modifications in techniques.
The camera port placement with open technique was mostly associated with gas leakage from the port site due to inadvertent enlargement of the skin incision during the creation of the space, leading to difficulty in further port placement in an already compromised RP space. The practice of putting extra sutures around and packing parts of gauze pieces, etc., did not work well. Subsequently, we started using the Hasson cannula with a blunt-tipped trocar that could be screwed in to accommodate the incision, and completely stopped the gas leakage. Its routine use is strongly recommended.
The correct placement of the balloon dilator for the creation of RP space is the most crucial initial step. In our earlier experience, extensive surgical emphysema had been noticed while insufflating the gas following use of Gaur's balloon. Retrospectively we felt that it happened in those with high body mass index (BMI) where the balloon inadvertently inflated in the intermuscular plane. The single digital dissection has been suggested as sufficient for adequate exposure of the RP space, where one could reduce the operating time by 5-15 min, which was usually required for balloon dissection. However, we did not find it useful. Following the initial space creation, we started using the transparent PBD balloon under vision, where the correct placement was confirmed before the final creation of space by distending the balloon up to 200 mL of air.
Landmarks in the retroperitoneum are relatively few compared with the peritoneal cavity. In addition, the limited skin area available may make port placement more difficult. Placement of the anterior ports may result in colonic injury due to inadequate peritoneal reflection, as occurred in the initial part of our series in two cases. We then modified our technique and started the anterior port placement after confirming that the peritoneum had been adequately reflected. Subsequently, a small-bore spinal needle was introduced through the anterior abdominal wall muscles, ensuring that it entered the retroperitoneum through the parietal muscle planes only [Figure 3]. Following the use of this technique, no case of colonic injury was reported in our series.
In this procedure, following the placement of the initial ports, excess RP fat may interfere with vision and further progress, causing repeated fogging of the lens and leading to the frustration and annoyance of the assistant and the surgeon. This was later successfully dealt with by excision and cauterisation of the overhanging fat. Fogging could also be reduced by keeping one nozzle of the port partially opened for degassing while the cautery or Harmonic (Ethicon, USA) was being activated.
Once all the ports were placed, the psoas muscle and Gerota's fascia were clearly identified; while the former is easily made out, the latter is leaf-thin and must be precisely incised in order to stay in the correct plane and for smooth progression of the surgery. Failure to do so results in unnecessary dissection with thinning of peritoneal flap and multiple rents.
Due to space limitations one has to do a more precise dissection near the hilum, as even a small amount of ongoing bleed or ooze may blur the landmarks and may thus significantly retard the progress in simple and radical nephrectomies. At the hilum, we suggest four-layer dissection techniques which involve the first layer of peri-hilar fat and lymphatics, followed by the renal artery, lymphatic tissue between the artery and vein, and at last the renal vein.
In our experience a tear at the peritoneum didn't always lead to conversion. Peritoneal tear can be managed by variety of techniques. An intravenous cannula could be inserted into the peritoneum to let the CO2 escape, thus reducing intra-peritoneal pressure and resulting in an expansion of RP space. Another option was to extend the tear intentionally to equalise the pressure on the two sides.
In paediatric patients, if an appropriate-sized balloon dilator is not available, the initial dilatation is done with a gloved finger mounted over a suction catheter, which is then inflated with normal saline for the creation of adequate space.
It has been established in the contemporary literature that for surgeries of the upper urinary tract such as simple and radical nephrectomy,,,,, partial nephrectomies,, adrenalectomies, renal cyst ablation, pyelolithotomy, ureterolithotomy and retrocaval ureter surgery,,, we prefer RP access and we have found that it affords certain distinct advantages.
Recent studies confirm that the operative duration, blood loss and complications for laparoscopic nephrectomies decrease with the increasing experience of the surgeon. A total of 3.5% of our patients required intra-operative blood transfusions. The blood losses are notably less peri-operatively compared to those in open surgery. Conversion to open or TP does not necessarily indicate a complication — rather, it reflects the appropriate judgement of the operating surgeon concerning the safety of the patents. The most common reason for conversion in our study was bleeding (in 8 patients). Apart from 1, none of these patients required blood transfusion. But even minor continuous bleeding often makes this approach difficult, due to limited space, and, moreover, repeated suctioning causes loss of pneumoperitonium. In our study, 3.2% of the patients had to be converted, similar to a number of findings from the contemporary literature.,, Apart from bleeding, the reason for conversion was: Technical difficulties (6 patients, 1.9%) related to a too-bulky mass, a mass adhering to the vascular pedicles, or loco-regional adenopathies preventing hilar dissection. Urgent conversion was done in 4 patients of radical nephrectomies due to bleeding from the hilum during dissection. One (1) of these patients had injury to the renal vein and 3 had bleeding from peri-hilar parasitic vessels. To avoid these complications, it is imperative that there is minimal handling or probing of the region of the renal hilum, especially in cases such as radical nephrectomies. A total conversion rate of 7.5% including 3% for peri-operative haemorrhages was reported by Rassweiller et al. Desai et al. have reported a conversion rate in 1.7% of cases secondary to haemorrhage in their series of more than 400 cases. The haemorrhagic accident is usually related to veins, because of their thin walls and friable nature. Liapis et al. have found bleeding from gonadal vessels and their retro-peritoneal branch vessels to be a reason for haemorrhagic complications, especially towards the end of the procedure during blunt dissection of the kidney and ureter. But in our series we never encountered bleeding during the later part of the procedure, during dissection of the kidney from surrounding structure. The use of a Harmonic or Ligasure (Covidien Medtronic, Minneapolis, USA) rather than blunt dissection of the kidney may be helpful to prevent such complications.
Elashry et al. has reported incisional hernia in 17% of patients after TP laparoscopic nephrectomy. The specimens were extracted intact via a lower abdominal transverse muscle-cutting incision. Incisional hernia is unusual after RS. We did not encounter any case of incisional hernia in our present study. In all these patients we have removed the specimen intact by enlarging a 10-mm port.
A total of 16 (5%) of the patients had post-operative complications, mostly related to the grade I and II as per MCC. Similar rates of complications in the RP laparoscopic approach has been reported in the literature by Liapis et al. and Kadji et al. It is worth mentioning that we found that urinoma in the retroperitoneum usually remains confined extraperitoneally, thus preventing urinary ascites or peritonitis. It is an added advantage of the RP approach. RP laparoscopy allows a faster and direct approach to the RP organs, and intra-peritoneal complications such as bowel injury, post-operative paralytic ileus and adhesions can be minimised or completely avoided. In this study, 2 patients had bowel injury during the placement of the third or fourth port in the early period of the learning curve. In both the patients there was severe intra-peritoneal adhesion secondary to previous surgery, preventing adequate peritoneal reflection. Subsequently we modified our technique of anterior port placement, confirming adequate reflection of the peritoneum with the help of a spinal needle, as described above. Following this modification, no case of colonic injury was encountered in our series. The pain of the pneumoperitoneum is less frequent with RS and thus the post-operative morbidity is reduced., Nevertheless, Desai et al. did not find significant difference in terms of hospital stay and consumption of analgesics between the RP and TP approaches. As we did not have a control group and ours not being a comparative study, it is difficult to comment on this.
After an initial 2 years' experience with about 50 cases, there was significant reduction in complication and conversion rates. Once the operating surgeons became experienced in RS, most of the technical problems could be managed easily and, furthermore, the complication rates reduced.
The few limitations of our study need to be discussed. The retrospective nature of our study design is the main drawback of our study. Related to this is the fact that our study was unable to ascertain the post-operative pain scores in our patients as we could not retrieve the relevant data.
| ¤ Conclusion|| |
Retroperitoneoscopy appears to be a safe, reproducible and effective technique for most types of upper urinary tract surgery, and has certain unique advantages. Most of the complications are of a minor grade and easily manageable. With the tips and tricks mentioned above, the younger urologist should be benefited and should find reduced the learning curve of RP urological surgery.
| ¤ References|| |
Clayman RV, Kavoussi LR, Soper NJ, Dierks SM, Meretyk S, Darcy MD, et al
. Laparoscopic nephrectomy: Initial case report. J Urol 1991;146:278-82.
Wittmoser R. Die Retroperitoneoskopie als neue Methode der lumbalen Sympathikotomie. Fortschr Endoscopie 1973;4:219-23.
Wickham JE. The surgical treatment of renal lithiasis. In: Wickham JE, editor. Urinary Calculus Disease. New York: Churchill Livingstone; 1979. p. 145-98.
Gaur DD, Agarwal DK, Purohit KC. Retroperitoneal laparoscopic nephrectomy: Initial case report. J Urol 1993;149:103-5.
Gill IS, Clayman RV, Albala DM, Aso Y, Chiu AW, Das S, et al
. Retroperitoneal and pelvic extraperitoneal laparoscopy: An international perspective. Urology 1998;52:566-71.
Clavien PA, Sanabria JR, Strasberg SM. Proposed classification of complications of surgery with examples of utility in cholecystectomy. Surgery 1997;111:518-26.
Kumar M, Kumar R, Hemal AK, Gupta NP. Complications of retroperitoneoscopic surgery at one centre. BJU Int 2001;87:607-12.
Mita K, Shigeta M, Mutaguchi K, Matsubara A, Yoshino T, Seki M, et al
. Urological retroperitoneoscopic surgery for patients with prior intra-abdominal surgery. Eur Urol 2005;48:97-101.
Gill IS, Schweizer D, Hobart MG, Sung GT, Klein EA, Novick AC. Retroperitoneal laparoscopic radical nephrectomy: The Cleveland clinic experience. J Urol 2000;163:1665-70.
Gill IS, Kavoussi LR, Clayman RV, Ehrlich R, Evans R, Fuchs G, et al
. Complications of laparoscopic nephrectomy in 185 patients: A multi-institutional review. J Urol 1995;154:479-83.
Liapis D, de la Taille A, Ploussard G, Robert G, Bastien L, Hoznek A, et al
. Analysis of complications from 600 retroperitoneoscopic procedures of the upper urinary tract during the last 10 years. World J Urol 2008;26:523-30.
Sebe P, de la Taille A, Hoznek A, Chopin D, Abbou CC, Salomon L. Simple nephrectomy with retroperitoneal laparoscopy. Prog Urol 2003;13:577-80.
Cicco A, Salomon L, Hoznek A, Saint F, Alame W, Gasman D, et al
. Results of retroperitoneal laparoscopic radical nephrectomy. J Endourol 2001;15:355-9; discussion 375-6.
Gill IS, Meraney AM, Schweizer DK, Savage SS, Hobart MG, Sung GT, et al
. Laparoscopic radical nephrectomy in100 patients: A single center experience from the United States. Cancer 2001;92:1843-55.
Hoznek A, Salomon L, Antiphon P, Radier C, Hafiani M, Chopin DK, et al
. Partial nephrectomy with retroperitoneal laparoscopy. J Urol 1999;1626:1922-6.
Pyo P, Chen A, Grasso M. Retroperitoneal laparoscopic partial nephrectomy: Surgical experience and outcomes. J Urol 2008;180:1279-83.
Salomon L, Soulié M, Mouly P, Saint F, Cicco A, Olsson E, et al
. Experience with retroperitoneal laparoscopic adrenalectomy in 115 procedures. J Urol 2001;166:38-41.
Chen Z, Chen X, Luo YC, He Y, Li NN, Wu ZH. Retroperitoneoscopic decortication of symptomatic peripelvic renal cysts: Chinese experience. Urology 2011;78:803-7.
Kadji JF, Armand C, Gimbergues P, Blanc F, Tostain J. Retrospective comparative study of extended nephrectomies by surgery and by retroperitoneal laparoscopy. Prog Urol 2001;11:223-30.
Rassweiler JJ, Seemann O, Frede T, Henkel TO, Alken P. Retroperitoneoscopy: Experience with 200 cases. J Urol 1998;160:1265-8.
Desai MM, Strzempkowski B, Matin SF, Steinberg AP, Ng C, Meraney AM, et al
. Prospective randomized comparison of transperitoneal versus retroperitoneal laparoscopic radical nephrectomy. J Urol 2005;173:38-41.
Thiel R, Adams JB, Schulam PG, Moore RG, Kavoussi LR. Venous dissection injuries during laparoscopic urological surgery. J Urol 1996;155:1874-6.
Elashry OM, Giusti G, Nadler RB, McDoughall EM, Dayman RV. Incisional hernia after laparoscopic nephrectomy with intact specimen removal: Caveat emptor. J Urol 1997;158:363-9.
McDougall EM, Clayman RV. Laparoscopic nephrectomy for benign disease: Comparison of the transperitoneal and retroperitoneal approaches. J Endourol 1996;10:45-9.
Hoznek A, Salomon L, Gettman M, Stolzenburg JU, Abbou CC. Justification of extraperitoneal laparoscopic access for surgery of the upper urinary tract. Curr Urol Rep 2004;5:93-9.
[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2], [Table 3], [Table 4]