AUTHOR AND EDITOR INFORMATION

Section 1 of 10  

• Authors and Editors
• Introduction
• Surgical Techniques
• Surgical Approaches
• Advantages and Disadvantages of Robotics Versus Laparoscopy
• Results
• Conclusions
• Acknowledgments
• Multimedia
• References

INTRODUCTION

Section 2 of 10  

• Authors and Editors
• Introduction
• Surgical Techniques
• Surgical Approaches
• Advantages and Disadvantages of Robotics Versus Laparoscopy
• Results
• Conclusions
• Acknowledgments
• Multimedia
• References

In 2007, prostate cancer was the most common newly diagnosed cancer among men in the United States. Although the incidence rates and mortality rates associated with prostate cancer have shown an overall declining trend, widespread screening and early diagnosis makes the management of clinically localized prostate cancer an ongoing challenge. After Walsh et al popularized the technique of anatomic nerve-sparing radical prostatectomy, open radical prostate surgery became a more desirable treatment for organ-confined prostate cancer.

The first successful laparoscopic radical prostatectomies were performed by Schuessler in 1992 and 1997.¹ Unfortunately, this technique did not gain widespread acceptance because of its extreme technical difficulty and because it offered no advantage over the criterion standard of open radical retropubic prostatectomy. The initial series reported operative times that ranged from 8-11 hours and a mean hospital stay of 7.3 days.

The laparoscopic approach gained new attention when two French groups published their experience with laparoscopic radical prostatectomy in 1999 and 2000.^{2, 3} They reported modifications to the original technique, resulting in operative times that ranged from 4-5 hours and a mean blood loss of 402 mL. The authors also reported a decreased mean hospital stay, due predominantly to earlier removal of the Foley catheter.

Even in the hands of these skilled laparoscopists, nerve-sparing dissection and construction of the urethrovesical anastomosis were demanding. With advances in medical technology, improved optics, and the widespread use of new laparoscopic instrumentation such as ultrasonic cutting and coagulating devices (eg, Harmonic scalpel; Ethicon Endo-Surgery, Inc; Cincinnati, Ohio), laparoscopic radical prostatectomy began to gain acceptance and was performed increasingly in several high-volume centers worldwide. However, the technical demands of laparoscopic radical prostatectomy prevented its widespread use by the average urologist and thus limited penetration.

The next significant advance in the surgical treatment of localized prostate cancer was the development of robotic surgical technology. Initially developed by the United States Department of Defense for use in military battlefield applications, robotic technology was adapted for civilian use through the entrepreneurial efforts of two rival corporations, Intuitive Surgical, Inc, and Computer Motion, Inc. These companies simultaneously developed robotic interfaces for use in human surgical applications. Computer Motion, Inc, introduced the Zeus Surgical System at approximately the same time that Intuitive Surgical, Inc, developed its da Vinci Surgical System.

Both technologies relied heavily on a laparoscopic patient-robot interface in which instruments were placed through small trocars implanted in the patient’s skin. The working field was maintained predominantly by insufflation of the peritoneal cavity with carbon dioxide. Subsequently, Intuitive Surgical, Inc, acquired Computer Motion, Inc, consolidating the robotic surgical technology and making Intuitive Surgical, Inc, the sole provider of advanced robotic technology for use in human surgical procedures.

Currently, several other companies develop and manufacture robotic surgical technology, including single robotic arms for laparoscopic cameras or as part of integrated minimally invasive operating-room systems, but none of these rival technologies can compete with the advanced robotic engineering by Intuitive Surgical, Inc.

The da Vinci Surgical System consists of a 3- or 4-armed robot connected to a remote console. The surgeon operates the system while seated at the console. Foot pedals are used for control, and 3-dimensional displays provide a unique and novel depiction of the surgical field not previously incorporated in other systems. Typically, 8- to 10-mm ports are used for the instruments, which have 7° of freedom, including rotation capabilities (ie, mimicking the movements of the human wrist), and a special robotic EndoWrist. The first reported robot-assisted laparoscopic prostatectomy using the da Vinci system was described by Abbou et al in 2001.⁴ Several other groups have also published their experience with the technique.^{5, 6}

Menon et al from the Vattikuti Urology Institute at Henry Ford Hospital in Detroit, Michigan, are responsible for the development and popularization of robotic radical prostatectomy.^{7, 8, 9, 10} This technique has been gaining widespread acceptance in the United States and Europe and is increasing in penetration worldwide. Robotic radical prostatectomy offers the advantages of the minimally invasive laparoscopic approach but shortens the learning curve, facilitating and hastening mastery of the procedure.

Although solid basic laparoscopic skills are required for access and assistance, the console surgeon role requires less laparoscopic skill. Therefore, the procedure is accessible to experienced open surgeons with minimal or no laparoscopic experience. In the most recent published report, Badani et al have performed more than 2700 robotic prostatectomies and have reported a mean operative time of 154 minutes, a mean blood loss of 100 mL, and hospital stays of less than 24 hours in 96.7% of patients.¹¹

For excellent patient education resources, visit eMedicine's Prostate Health Center, Cancer and Tumors Center, and Men's Health Center. Also, see eMedicine's patient education articles Prostate Cancer, Prostate Infections, Enlarged Prostate, and Causes of Erectile Dysfunction.

For additional information on prostate cancer, visit Medscape's Prostate Cancer Resource Center.

SURGICAL TECHNIQUES

Section 3 of 10  

• Authors and Editors
• Introduction
• Surgical Techniques
• Surgical Approaches
• Advantages and Disadvantages of Robotics Versus Laparoscopy
• Results
• Conclusions
• Acknowledgments
• Multimedia
• References

The basic technique for performing minimally invasive radical prostatectomy is the same regardless of the technology used. Candidates for this approach include patients in whom the diagnosis and staging support organ-confined prostate cancer and in whom the appropriate metastatic workup results are negative. The goal of minimally invasive radical prostatectomy is to laparoscopically resect the prostate and its capsule, along with the seminal vesicles. The procedure can be performed either extraperitoneally or, more commonly, transperitoneally. The two most reported techniques for performing minimally invasive radical prostatectomy are robotic (robotic radical prostatectomy) and laparoscopic (laparoscopic radical prostatectomy).

Laparoscopic radical prostatectomy

The laparoscopic approach involves 2-dimensional monitors and conventional laparoscopic instruments (5 or 10 mm) with a 10-mm 0° and/or 30° telescope. The camera may be operated by a one-armed camera holder or by an assistant. The use of a single voice-operated robotic arm has also been described as an adjunct to the laparoscopic approach. A camera-holding device provides stability and prevents camera shake that can result from holding it by hand (ie, by an assistant).

Robotic radical prostatectomy

Currently, the only available integrated robotic surgical system is the da Vinci Surgical System (Intuitive Surgical, Inc; Sunnyvale, California). This computer-aided system has a basic master-slave design. A second generation of this system is currently available (da Vinci S HD System). The basic design is as follows:

• Surgeon console: This is the user interface of the robot for the surgeon. It consists of the following:
• • Display system: The system is a 3-dimensional stereoscopic display for the console surgeon and is generally available for view in 2-dimensional form by assistants and observers.
  • Master arms: These are the controls the surgeon uses for making surgical movements. Movements of the master arms translate to real-time movements of the instrument tips and may be scaled for fine movements. The master arms also provide basic force feedback to the surgeon but are limited in their ability to discriminate complex haptic feedback. Camera movements are controlled with a clutch mechanism. In the 4-arm systems, the surgeon can toggle between instruments.
  • Control panel: The control panel is used to adjust the surgeon console display and control options. The control panel allows toggling between 2- and 3-dimensional display, adjusting various levels of scaling, and choosing the camera perspectives (0° vs 30° lens).
  • Central processing unit: This is the computer that controls the system and integrates and translates robot control inputs from the surgeon.
• Robotic arms: Two or 3 arms are provided for mounting surgical instruments and one camera arm is provided for camera manipulation. The robotic arms are mounted on a surgical cart that is sterilely draped and moved into position over the patient. The arms are then mounted to 8-mm trocars placed through the patient's abdominal wall. The surgeon console is connected to the surgical cart via cables. Although the surgeon console and the surgical cart are typically in close proximity in the operating room, a longer interface has the potential to be used for long-distance surgery or telementoring.

SURGICAL APPROACHES

Section 4 of 10  

• Authors and Editors
• Introduction
• Surgical Techniques
• Surgical Approaches
• Advantages and Disadvantages of Robotics Versus Laparoscopy
• Results
• Conclusions
• Acknowledgments
• Multimedia
• References

Patient preparation and positioning for minimally invasive radical prostatectomy

Once the patient is confirmed as an appropriate candidate for a complex laparoscopic procedure, he must undergo an appropriate preoperative preparation to minimize complications and to facilitate operative success. The authors' standard preoperative regimen consists of an extended office visit with the patient to explain the risks, benefits, and potential alternatives of the procedure. The patient receives details of the robotic technology in the form of patient-centered brochures. The patient is also directed to the institution's Web site, which contains extensive information on what the patient should expect before, during, and after the procedure.

The authors' standard surgical consent form emphasizes the complications that are inherent to laparoscopic techniques. The priorities of the procedure are also emphasized, including patient safety, preservation of the oncologic integrity of the surgical procedure, and an attempt at performing the procedure laparoscopically. The risk of conversion to an open procedure is explained thoroughly in the framework of this group of priorities. Specifically, if the patient's safety or the oncologic integrity of the operation is jeopardized, the attending surgeon may decide to convert the procedure to the open surgical technique.

The preoperative and preanesthesia screening to determine suitability for a complex laparoscopic procedure is identical to that performed prior to open surgery. The authors generally perform a preoperative bowel preparation, including both antibiotic and mechanical bowel cleansing. This not only reduces bowel distention and adds visualization but also reduces the potential for infection due to the spillage of bowel contents in the uncommon event of a bowel perforation. On the day of surgery, a preoperative enema is performed, sequential compression stockings are placed, and a large-bore intravenous line is begun with preoperative antibiotics that cover both genitourinary and skin flora.

Regardless of the technique used, the patient is placed in the supine position with his head down. This head-down position allows for gravity to facilitate the natural retraction of the pelvic tissues. If the procedure is to be performed transperitoneally, a periumbilical incision is made to provide access for the initial laparoscopic port. A Veress needle or Hasson-type trocar is used to establish pneumoperitoneum and to facilitate the laparoscopic survey of the abdomen. The Veress needle is an ideal access device when the patient has no history of abdominal surgery. In patients who have undergone previous abdominal surgery, particularly involving infraumbilical incisions, the Hassan trocar is ideal for direct visualization and confirmation of entrance into the peritoneal cavity.

Carbon dioxide is then insufflated into the abdomen to achieve pneumoperitoneum. If a Veress needle was used for initial access, it is replaced by a 12-mm radially dilating laparoscopic trocar. The 3-dimensional robotic laparoscope is then inserted through the infraumbilical trocar site, and a laparoscopic survey of the abdomen and pelvis is performed. If the procedure is to be performed extraperitoneally, the first steps for access consist of a small incision and development of the extraperitoneal space.

Robotic Transperitoneal Approach

The transperitoneal approach to robotic radical prostatectomy was developed and popularized by Menon et al at the Vattikuti Urology Institute at Henry Ford Hospital in Detroit, Michigan. In this technique, the dissection proceeds in an antegrade manner and releases the prostate from the bladder neck early in the procedure, allowing the prostate to be manipulated with traction to aid in visualization for nerve sparing. The seminal vesicles and all subsequent dissection proceed in the direction of telescope vision (ie, antegrade), facilitating visualization.

The patient is placed in the supine position, secured to the table, and placed in steep Trendelenburg position (45°). The legs can be placed in stirrups or positioned apart. The robot is then brought between the patient's feet. The total number of ports and port configurations depends on several factors. Three-armed robots have a total of 6 ports in an inverted V-shaped configuration. The Veress needle is used to establish the pneumoperitoneum, and a 12-mm port is placed just to the left of the umbilicus (camera port). A 30° upward-looking lens is then used to place the remaining ports; two 8-mm ports are placed as mirror images of each other, 10-12 cm from the camera port and 2 fingerbreadths below it. The ideal port position is approximately 15 cm above the pubic symphysis to afford the instrument adequate length of excursion.

Two ports are placed in the right lower quadrant—(1) a lateral 10-mm port just above the right anterior superior iliac spine for retraction and passage of sutures and (2) a medial 5-mm port for suction and irrigation midway and slightly inferior to the umbilicus and right robotic port. Finally, a 5-mm left lateral port is placed as a mirror image of its right-sided counterpart. Initially, this procedure called for two bedside assistants, but the evolution and application of the fourth robotic arm eliminated the need for one of the assistants, in turn obviating the need for the most lateral left 5-mm port.

The port placement of a da Vinci system with a 4-arm configuration is similar except the assistant is usually relegated to the left side and two right lateral ports are 8-mm robotic trocars. The assistant can then use either one or two of the ports on the left side. At least one 10-mm trocar is necessary for suture passage. The authors use a single 10-mm trocar with the port placed about 2 fingerbreadths above the umbilicus on the left. Although this trocar position necessitates the use of a extended-length (bariatric) suction irrigator, the more cephalad positioning of the trocar discourages movement conflicts with the left robotic arms. Careful trocar positioning is more important with the first-generation 3-arm and 4-arm systems. The newer da Vinci S was designed to have a smaller profile for camera and instrument arm movement, thereby making precise trocar placement less vital.

The robot is then docked, and the robotic instrument ports and the camera port are fixed to the arms of the robot. This portion of the procedure is initially time-consuming but becomes much shorter with experience. This step routinely takes 10-15 minutes at the authors' institution.

A stepwise approach to robotic transperitoneal prostatectomy is discussed below. Instruments used include a bipolar cautery on the left robotic arm (left hand) and a monopolar cautery scissors or hook/spatula on the right robotic arm (right hand). If a fourth robotic arm is used, large grasping forceps (Cadiere or Prograsp) are also used.

Early posterior dissection – Exposure of seminal vesicles and development of a plane between the prostate and rectum

Some surgeons use a posterior approach for dissection of the seminal vesicles and identification of the plane between the prostate and rectum. This step is performed using a 0° lens. The bowel is pulled superiorly and the rectum identified. The peritoneal reflection is incised in the midline, and blunt dissection is used to identify the ampulla of the vas and the seminal vesicles. Care should be taken to stay in the midline, as the insertion of the ureters in the trigone of the bladder occurs laterally. The vasa can then be dissected and divided bilaterally. The peritoneal reflection is divided slightly more laterally; the seminal vesicles are then encountered.

The seminal vesicles are then freed inferiorly and laterally and the vessels at the tip are divided bilaterally. By retracting the vasa and the seminal vesicles superiorly, the plane between the posterior prostate and the rectum can be easily developed under direct visualization. This plane is carried caudally to the prostatic apex. Care is taken to avoid lateral dissection because of the proximity to the neurovascular bundles. After this plane is well developed, attention is again turned to the development of the extraperitoneal space.

Some surgeons do not routinely use the posterior approach initially and instead dissect the seminal vesicles with anterior traction after separating the bladder neck from the prostate.

Development of the extraperitoneal space

This step is performed using a 30° upward-looking lens. A transverse peritoneal incision is made extending from the left to the right medial umbilical ligament and extended in an inverted U-shaped manner to the level of the vasa on either side. The vasa can also be divided at this point to aid in bladder mobility. The extraperitoneal space is developed after the medial and median umbilical ligaments are transected, allowing the bladder, prostate, and bowel to drop posterior and the remainder of the operation to be performed extraperitoneally. Some authors fill the bladder to help identify the planes of dissection and to aid in dropping the bladder posteriorly.

Lymph node dissection

A 0° lens is used for optimum visualization, and 1:3 scaling is used for lymphadenectomy. Lymphadenectomy is performed at the surgeon's discretion if the preoperative serum prostate-specific antigen (PSA) value exceeds 10 ng/mL, the biopsy Gleason score is greater than 6, or more than 50% of the biopsy cores are positive for cancer. The anatomic boundaries of the limited bilateral pelvic nodes dissection include the iliac artery superiorly, the obturator nerve inferiorly, the ilac bifurcation cranially, and the obturator fossa caudally. The nodal package is sent for frozen-section analysis only if the nodes appear grossly enlarged.

Exposure of prostatic apex and endopelvic fascia

The 0° lens with 1:3 scaling is used for this part of the dissection. This endopelvic fascia is incised after the prostate is retracted medially with the da Vinci cautery scissors or hook. The fascia is incised from the urethra distally to the prostatovesical junction proximally. Blunt dissection allows sweeping of the levator muscle from the lateral surface of the prostate. Dissection is carried distally until the urethra, with the surrounding puboperinealis muscle, is exposed.

Dorsal vein stitch

The nonscaled setting is used for this step. A figure-of-eight stitch is placed around the dorsal venous complex using a 6-inch, 1-0 polyglactin suture on a CT-1 36-mm taper needle. An additional suture is placed midway between the apex and base of the prostate for traction and rotation of the prostate during posterior dissection.

Retroapical dissection and release of the neurovascular bundle

The plane behind the prostatourethral junction is developed using a combination of blunt and sharp dissection. This dissection helps enormously to precisely identify the posterior apical margin of the prostate at the time of detachment of the specimen.

Bladder neck transection

The assistant provides vertical traction on the prostatic suture, and the anterior wall of the bladder is incised until the Foley catheter is observed. The assistant then retracts the catheter to provide countertraction as the posterior bladder wall is cut. Sparing of the bladder neck is possible but uncommon. The bladder neck incision is elliptical so that the posterior lip is slightly longer than the anterior lip. This maneuver aids in visualization of the posterior suture line during anastomosis. Using the da Vinci bipolar forceps, the surgeon grasps the cut end of the posterior bladder neck in the midline and gradually dissects it away from the prostate. The anterior layer of Denonvilliers aponeurosis (fascia) is then exposed and incised, exposing the vasa and seminal vesicles.

If the seminal vesicles were previously released, the plane is easily entered. However, if the surgeon did not elect to use an initial posterior approach, at this point, the left assistant retracts the posterior lip of the prostate anteriorly while the fourth robotic arm depresses the bladder posteriorly to provide a clear operative field for dissection of the seminal vesicles and vas deferens. The vasa are transected, and the seminal vesicles are skeletonized, avoiding damage to the neurovascular bundles.

Once the seminal vesicles are freed, the left assistant retracts the seminal vesicles anteriorly. At this point, the posterior layer of Denonvilliers aponeurosis can be observed between the two lateral prostatic pedicles. This fascia is incised close to the prostate, and a plane between the prostate anteriorly and the rectum posteriorly is developed. The plane of dissection leaves the most posterior layer(s) of Denonvilliers aponeurosis on the rectum. This dissection is carried down to the apex of the prostate.

Control of the lateral pedicles and the veil of Aphrodite (preservation of the neurovascular bundles)

The lateral pedicles at the prostate vesical junction are controlled using Hem-o-lock clips and/or bipolar coagulation.¹² The clips are applied close to the prostate, and the pedicle is divided between them. Once the dissection enters the plane between the prostatic fascia medially and the levator fascia laterally, electrocautery is avoided and the anterior nerve-sparing dissection proceeds using sharp cutting with scissors and blunt dissection using the grasper. This dissection proceeds distally to the puboprostatic ligaments.

Several authors have also advocated a completely cautery-free or athermal dissection of the lateral pedicles to avoid any inadvertent damage to the neurovascular bundle. This can be achieved with laparoscopic bulldog clamps and oversewing of the neurovascular bundle for hemostasis. Although results of this technique have not been validated in large series, minimizing the use of cautery or other thermal hemostatic instruments during dissection near the neurovascular bundle seems prudent.

Incision of the dorsal venous complex and urethra

This is the final step of the dissection. Using a 0° lens with 1:3 scaling, the dorsal venous complex is incised tangentially to the prostate to avoid capsular incision. A plane between the urethra and dorsal venous complex is gently developed to expose the anterior urethral wall. The Foley catheter is reinserted and used to identify the anterior surface of the urethra at the urethroprostatic junction. The anterior wall of the urethra is transected with the scissors a few millimeters distal to the apex of the prostate. The posterior wall of the urethra and the rectourethralis muscle are cut under direct vision. The freed specimen is then examined for adequacy of resection margins and is placed in a specimen-retrieval bag.

Urethrovesical anastomosis

Urethrovesical anastomosis is performed using a hybrid tied suture, which consists of two 3-0 Monocryl sutures (one dyed and the other undyed) tied to each other to form a double-ended suture on RB-1 needles, each 6 inches long. Some authors advocate the use of a similarly constructed Vicryl suture, although this suture may prove to be more difficult to tighten prior to ligation.

The initial throw is placed outside in the bladder at the 5-o'clock position, and the dyed suture is pulled through so that the knot lies securely on the outside wall of the bladder posteriorly. The dyed suture is then used as a running stitch to suture the posterior bladder wall to the urethra. The dominant hand is used for the urethral pass, and the nondominant hand is used for the vesical pass. Approximately 5-6 throws are made posteriorly, with the assistant placing slight tension on the suture, if necessary. At the corner, the surgeon reverses the suture within the bladder lumen and passes the suture outside-in on the urethra.

The post suture ends at the 11-o'clock position and is held on traction by the left assistant to prevent loosening of the stitch. The undyed suture is then used to perform the anterior part of the urethrovesical anastomosis extending from the 5-o'clock position to the 12-o'clock position. The two sutures are then tied to each other to complete the anastomosis. The bladder is irrigated with 200 mL of saline to look for any leaks. Any leaks are reinforced with sutures. A new 20F indwelling Foley catheter is placed, and the balloon is filled with 30 mL. The specimen is retrieved and ports closed.

Robotic Extraperitoneal Approach

In 2001, Abbou et al, from Hopital Henri Mondor, Creteil, France, published their technique using a completely robotic extraperitoneal approach.⁴ The patient is placed supine in a 15° Trendelenburg position. A 3-cm horizontal incision is made 1 fingerbreadth below the umbilicus, and the preperitoneal space is entered. A blunt port Hasson canula is placed, and the preperitoneum is insufflated to 18 mm Hg. The space of Retzius is developed by blunt dissection using a conventional laparoscope until the pubic symphysis is reached. A 5-mm port is then placed in the midline 2 fingerbreadths above the symphysis to further develop the retropubic space. The right and left extraperitoneal robotic instrument ports are placed 4 cm below the camera port at the pararectal line. Two additional assistant ports are placed on the right side, the first at the level of the umbilicus above the right robotic instrument port and the second to the right and in line with the right robotic instrument port.

The procedure essentially follows the same steps of the robotic prostatectomy described above, but the dissection is entirely extraperitoneal. The Creteil group uses a 2-0 polyglactin on a 26-mm needle for the dorsal venous stitch and a 3-0 polyglactin on a five-eighths circle tapered cutting needle for the running vesicourethral anastomosis.

Laparoscopic Transperitoneal Approach

The widely used transperitoneal approach is the Montsouris technique described by Guillonneau and Vallancien from the Institut Mutualiste Montsouris, University Pierre et Marie Curie, Paris, France.¹³ The patient is placed supine with the arms at the sides and the legs spread apart and in an extreme Trendelenburg position. One surgeon and one assistant perform the operation, with a right-handed surgeon standing on the left side of the patient. The Montsouris group uses the AESOP voice-controlled robot to hold the telescope.

Five ports are placed in a diamond configuration, (1) a 10-mm telescope port at the umbilicus, (2) a 10-mm port at the McBurney point, (3) a 5-mm port at the midpoint between the umbilicus and the pubis symphysis in the midline, (4) a 5-mm port at the midpoint between the left anterior superior iliac spine and the umbilicus, and (5) the final 5-mm port at the right pararectal line at the level of the umbilicus. The abdomen is initially inspected, and a pelvic lymphadenectomy is performed, if required.

The procedure is begun with incision of the peritoneal fold between the rectum and bladder and the dissection of the seminal vesicles posteriorly. The seminal vesicles are retracted anteriorly, and the Denonvilliers aponeurosis is incised. The dissection is carried distally to the level of the rectourethral muscle, separating the prostate anteriorly from the rectum posteriorly. Attention is then directed anteriorly, and the peritoneum is incised to enter the space of Retzius, thereby causing the bladder to fall posteriorly. The endopelvic fascia is incised, and the levator muscle is pushed laterally to free the prostate gland. This is followed by ligation of the dorsal vein. The next step is incision of the bladder neck.

Finally, the lateral pedicles are dissected, and the urethra is transected to free the prostate gland with the seminal vesicles. The final step of the surgery is construction of the urethrovesical anastomosis. The Montsouris group performs the anastomosis with interrupted 3-0 resorbable sutures on a five-eighths needle. A total of 8 sutures are placed. Finally, a drain is placed and the ports closed.

The advantages of the transperitoneal approach include familiarity with anatomy, adequate space for dissection, and the presence of several reference points to aid the surgeon in orientation. Maximum mobility of the bladder is achieved in this approach, which helps provide a tension-free urethrovesical anastomosis.

Disadvantages of the transperitoneal approach include communication of the anastomotic site to the peritoneal cavity with the potential for peritoneal urine leak and ascites. The transperitoneal approach also increases the risk of bowel injury, ileus, and adhesions.

Rassweiler et al from Klinikum Heilbronn, University of Heidelberg, Heilbronn, Germany, published a modification of the transperitoneal technique.⁶ They used a W-shaped port placement with 5 ports placed initially transperitoneally. The sixth port is placed in the right lower abdomen after access to the space of Retzius. The dissection is started distally, with incision of the endopelvic fascia, ligation of the dorsal venous complex, and transection of the urethra. The Foley catheter is held and pulled cephalad for retraction. The prostate is dissected starting distally and progressing proximally with division of the Denonvilliers aponeurosis to separate the rectum posteriorly. The lateral pedicles are clipped, and the neurovascular bundles are spared.

Once this part of the procedure is completed, the dissection shifts to the bladder neck, which is transected. The Foley catheter is then used as a loop retractor, and the vasa and seminal vesicles are dissected off the posterior bladder. Finally, urethrovesical anastomosis is performed with a 15- to 17-cm 3-0 polydioxanone suture on an RB-1 needle using 5 interrupted sutures at the 6-o'clock position, followed by sutures at the 5-, 3-, 7-, and 9-o'clock positions, respectively.

Laparoscopic Extraperitoneal Approach

This approach was first described by Raboy, from Staten Island University Hospital, Staten Island, New York, in 1997 as a simulation of the open retroperitoneal approach to the prostate. The patient preparation, position, and draping are similar to the transperitoneal technique except that a steep Trendelenburg position is unnecessary.

A 1-cm infraumbilical incision is made and carried down to the preperitoneal space, which is bluntly dissected, and a Hasson canula is placed in this space. The extraperitoneal space is then developed by either blunt dissection using additional trocars or by using a visual balloon-dilating trocar or Gaur balloon dilator. Once the space is developed, the steps of the surgery mimic those of the transperitoneal approach except that the seminal vesicles and vas are dissected after the bladder neck is transected.

Theoretical advantages of this approach include its feasibility in patients who have undergone extensive abdominal surgeries and its minimal associated risk of bowel injury. The peritoneum acts as a self-retractor for the intestines, thus obviating the need for steep Trendelenburg positioning. Reports of simultaneous inguinal hernia repairs using prosthetic mesh have been published. The most significant limitation of this approach is the lack of adequate space for dissection and suturing. Also, because the peritoneal and urachal attachments of the bladder are not divided, tension at the urethrovesical anastomosis is a concern. As a result, the extraperitoneal approach should be performed only by experienced laparoscopic surgeons.

ADVANTAGES AND DISADVANTAGES OF ROBOTICS VERSUS LAPAROSCOPY

Section 5 of 10  

• Authors and Editors
• Introduction
• Surgical Techniques
• Surgical Approaches
• Advantages and Disadvantages of Robotics Versus Laparoscopy
• Results
• Conclusions
• Acknowledgments
• Multimedia
• References

The robotic techniques have several advantages over laparoscopic techniques for performing radical prostatectomy.

• Because the display system of the da Vinci projects the image in the direction of the surgeon's hands, the optically correct hand-eye coordination is restored. This is more difficult with laparoscopy, in which the camera is sometimes offset to the plane of dissection.
• The 11-mm telescope in the da Vinci system is a combination of two 5-mm optical channels (one for the right and one for the left eye), which have 2 separate 3-chip–charged coupling devices in the camera head. The 2 images are displayed to provide 3-dimensional stereoscopic vision to the surgeon, providing depth perception lacking in laparoscopy. The conventional laparoscopic technique does not provide a 3-dimensional depth of view.
• The movements of the robotic system are intuitive (ie, a movement of the master control to the right causes the instrument to move to the right), as opposed to the counterintuitive movements in laparoscopy with fulcrum movement effects (ie, movement of the laparoscopic instrument to the right by the surgeon causes the tip of the instrument to move to the left inside the patient's body).
• The robotic systems provide increased precision by filtering hand tremors, providing magnification (10X or 15X), and providing scaling for the surgeon's movements (a 1:3 scaling means that a 3-in movement of the master is translated into a 1-in movement of the instrument tip).
• The robotic instruments have articulated tips, which permit 7° of freedom in movements (ie, they mimic human wrist movements, including rotation), which is unlike laparoscopy, with which only 4° of freedom are permitted.

Robotic techniques also have disadvantages.

• The current-generation robot is still bulky and tends to limit the working space of the assistant(s).
• The availability of instrumentation for the robotic systems is presently limited, although development of new instruments is ongoing.
• Economically, the robotic system is viable only for centers with a high volume of cases or multidisciplinary robotic use. The system cost exceeds $1.2 million, and the annual maintenance costs range from $100,000-$150,000.

RESULTS

Section 6 of 10  

• Authors and Editors
• Introduction
• Surgical Techniques
• Surgical Approaches
• Advantages and Disadvantages of Robotics Versus Laparoscopy
• Results
• Conclusions
• Acknowledgments
• Multimedia
• References

The results of minimally invasive radical prostatectomy can be categorized as operative, referring to perioperative and delayed complications, and functional, referring to oncologic efficacy, erectile function, and continence.

Laparoscopic Radical Prostatectomy

Operative outcomes

The major advantages of laparoscopic radical prostatectomy over open radical prostatectomy relate to lower blood loss and transfusion rates, lower perioperative morbidity and analgesic requirements, and quicker convalescence, including early return to work.^{2, 3, 13, 14, 15, 16, 17}

Below is a summary of representative large published series from major centers experienced in laparoscopic radical prostatectomy. The pioneering effort of European centers with this complicated technique should be noted.

Table 1. Outcomes of Operative Parameters Using Laparoscopic Radical Prostatectomy

As can be appreciated, the mean operating-room time for laparoscopic radical prostatectomy is approximately 4.5 hours. However, note that European centers report longer hospitalization times than US hospitals. The laparoscopic approach compares very favorably with open radical prostatectomy in terms of blood loss, hospital stay, and catheterization times. Operative times for laparoscopic prostatectomy are significantly longer than for open surgery, even after the learning curve has been mastered.

Functional outcomes

Relatively few studies have discussed functional outcomes following laparoscopic radical prostatectomy. Most series are from the same European laparoscopic centers of excellence.

Table 2. Outcomes of Functional Parameters Using Laparoscopic Radical Prostatectomy

Continence rates vary from 85-90%, and potency rates range from 40-59.9% according to unilateral or bilateral bundle preservation. Patient self-reported survey results are probably more reflective of morbidity results because the ratings of physicians and patients may be divergent. Especially in embarrassing clinical aspects, such as sexual and urinary symptoms, physician and patient assessments may have significant differences, as reported by Penson and Litwin in 2003.²² The much greater postoperative sexual and urinary dysfunction rates reported in recent surveys of patients after radical prostatectomy support that concept.

Preservation of neurovascular bundles, younger patient age, and an experienced surgeon are the main factors associated with the best results regarding erectile function; however, these factors are similar for both open and laparoscopic approaches.^{7, 23, 24}

Earlier concerns of higher positive margin rates following laparoscopic radical prostatectomy have been shown to be incorrect in published series.^{16, 25, 17, 26}

Robotic Radical Prostatectomy

Operative outcomes

Robotic radical prostatectomy has gained substantial momentum largely because of factors discussed above, including a shorter learning curve and increased accessibility. Multiple large published series have reported operative outcome data. Of these, the Henry Ford Hospital (Detroit, Michigan) has the largest patient experience with robotic prostatectomy.

Table 3. Outcomes of Operative Parameters Using Robotic Radical Prostatectomy

Robotic radical prostatectomy offers significantly lower operative times and blood loss than laparoscopic or open surgery. Catheterization times and hospital stay are also superior to those associated with open and laparoscopic approaches.^{29, 10, 12} The learning curve is less with robotic assistance compared with laparoscopy. The one significant question that remains unanswered pertains to the cost-effectiveness of robotic prostatectomy compared with open and laparoscopic radical prostatectomy.

Functional outcomes

Long-term follow-up after robotic prostatectomy is not available because the technique is relatively new; however, early functional results are available and are summarized below.

Table 4. Outcomes of Functional Parameters Using Robotic Radical Prostatectomy

Preliminary results from the above series show that oncologic and functional results following robotic prostatectomy compare very favorably with those of either open or laparoscopic radical prostatectomy.^{7, 8, 9, 10, 12} The margin rates and rates of PSA recurrence are similar, but potency and continence rates are better than those of open and laparoscopic approaches.^{7, 8, 10} The excellent results reported from several large-volume centers suggests that the data are reproducible with appropriate surgical volume. Long-term functional and oncologic results are needed to establish the role of robotic radical prostatectomy in the treatment of localized prostate cancer.

Table 5. Oncologic Outcomes with Laparoscopic and Robotic-assisted Laparoscopic Radical Prostatectomy

Comparative Studies

Relatively few studies have directly compared robotic or laparoscopic radical prostatectomy with open radical retropubic prostatectomy. Even fewer studies have compared pure laparoscopic prostatectomy with robotic prostatectomy. Because of the inherent difficulty with performing a prospective randomized trial for minimally invasive prostatectomy, most studies are designed as case-matched control studies.

Tooher et al (2006) published a systematic review of comparative studies involving laparoscopic prostatectomy.³² Twenty-one studies compared laparoscopic prostatectomy with open prostatectomy, with a total of 2301 and 1757 patients, respectively. The authors concluded that the literature shows laparoscopic prostatectomy is associated with a longer operative time but results in shorter hospital stays and duration of catheterization. Based on the available studies, the authors concluded that the two procedures yielded similar positive-margin rates and recurrence-free survival. The authors criticized the overall poor reporting in terms of functional outcomes such as continence and potency but suggested that the two techniques appeared to yield similar results.

Rozet et al (2007) compared 133 laparoscopic prostatectomies to a case-matched 133 robotic-assisted laparoscopic prostatectomies.³³ They found few differences in terms of operative parameters. They concluded that the two procedures were equivalent with respect to operative time, blood loss, hospital stay, length of catheterization, and positive-margin rate.

Smith et al (2006) from Vanderbilt University attempted a prospective study to compare blood loss between robotic-assisted radical prostatectomy and radical retropubic prostatectomy.³⁴ The choice of the procedure choice was left up to the patient; 176 elected robotic prostatectomy and 103 elected open radical prostatectomy. The authors found that the robotic procedure yielded less intraoperative blood loss and a higher hematocrit at the time of hospital discharge. The transfusion rate (very low in both groups) did not differ.

CONCLUSIONS

Section 7 of 10  

• Authors and Editors
• Introduction
• Surgical Techniques
• Surgical Approaches
• Advantages and Disadvantages of Robotics Versus Laparoscopy
• Results
• Conclusions
• Acknowledgments
• Multimedia
• References

Most of the major leaps in the evolution of minimally invasive surgical treatments for prostate cancer have been driven by the efforts of only a few pioneering groups. These groups are to be commended for their hard work and commitment to improving these complex procedures. Although laparoscopic radical prostatectomy still requires considerable technical skill, robotic technology has bridged the gap for open surgeons to perform these complex procedures.

The literature supports improved operative and perioperative parameters with minimally invasive techniques, including decreased blood loss, shorter hospital stay, and decreased time of catheterization. In the available studies, both laparoscopic and robotic prostatectomy seem to improve functional parameters, namely potency and continence, compared with open prostatectomy. Unfortunately, these studies are usually reported by high-volume single-center experiences and are criticized for their reproducibility across multiple centers and levels of surgeon experience. Reported oncologic outcomes for laparoscopic and robotic prostatectomy are comparable with those of open series, although long-term oncologic data are currently limited.

As the penetration of robotics increases, urologists are challenged to adapt to the rapid changes in this procedural technology. This raises challenges both for established urologists and for urology training programs. Little has been done to establish firm parameters in terms of case volume and operative learning curve, and most large centers are in a constant state of procedural evolution intended to improve clinical outcomes. Finally, the definitive prospective, randomized clinical trial comparing laparoscopic or robotic prostatectomy to open radical prostatectomy would be very difficult to perform given the reported benefits from the minimally invasive procedures. The highest level of achievable data will likely be a well-performed meta-analysis of the literature intended to confirm the consistency of data between clinical centers and individual surgeons.

ACKNOWLEDGMENTS

Section 8 of 10  

• Authors and Editors
• Introduction
• Surgical Techniques
• Surgical Approaches
• Advantages and Disadvantages of Robotics Versus Laparoscopy
• Results
• Conclusions
• Acknowledgments
• Multimedia
• References

The authors would like to acknowledge the Vattikuti Urology Institute and Henry Ford Health System for providing the high-quality intraoperative photographs presented in this article.

MULTIMEDIA

Section 9 of 10  

• Authors and Editors
• Introduction
• Surgical Techniques
• Surgical Approaches
• Advantages and Disadvantages of Robotics Versus Laparoscopy
• Results
• Conclusions
• Acknowledgments
• Multimedia
• References

Media file 1:  Laparoscopic and robotic radical prostatectomy. Incision of the medial umbilical ligament. Courtesy of Vattikuti Urology Institute - Henry Ford Health Systems.
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Media file 2:  Laparoscopic and robotic radical prostatectomy. Division of the urachus and entry into the space of Retzius. Courtesy of Vattikuti Urology Institute - Henry Ford Health Systems.
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Media file 3:  Laparoscopic and robotic radical prostatectomy. Incision of the endopelvic fascia. Courtesy of Vattikuti Urology Institute - Henry Ford Health Systems.
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Media file 4:  Laparoscopic and robotic radical prostatectomy. Incision of the bladder neck. Courtesy of Vattikuti Urology Institute - Henry Ford Health Systems.
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Media file 5:  Laparoscopic and robotic radical prostatectomy. Dissection of the seminal vesicles. Courtesy of Vattikuti Urology Institute - Henry Ford Health Systems.
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Media file 6:  Laparoscopic and robotic radical prostatectomy. Clipping of the prostatic pedicle. Courtesy of Vattikuti Urology Institute - Henry Ford Health Systems.
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Media file 7:  Laparoscopic and robotic radical prostatectomy. Division of the urethra. Courtesy of Vattikuti Urology Institute - Henry Ford Health Systems.
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Media file 8:  Laparoscopic and robotic radical prostatectomy. Anastomosis. Courtesy of Vattikuti Urology Institute - Henry Ford Health Systems.
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Media file 9:  Laparoscopic and robotic radical prostatectomy. Anastomosis. Courtesy of Vattikuti Urology Institute - Henry Ford Health Systems.
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REFERENCES

Section 10 of 10

• Authors and Editors
• Introduction
• Surgical Techniques
• Surgical Approaches
• Advantages and Disadvantages of Robotics Versus Laparoscopy
• Results
• Conclusions
• Acknowledgments
• Multimedia
• References

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Article Last Updated: Sep 29, 2008