Posterior Approach

Step 1: Posterior Dissection of the Prostate

Dissection of the Seminal Vesicles

The retrovesical cul-de-sac is inspected and the first landmarks are the vas deferens behind the pertoneum and transverse semicircular peritoneal folds at the inferoposte-rior aspects of the bladder on both sides.

The more superior of these peritoneal folds represents the approximate location of the ureters and should be avoided. The more inferior fold, nearly at the depth of the peritoneal reflection, is created by the meeting of the vasa deferentia in the midline, with the seminal vesicles lying just lateral.

As described by Abbou et al. (6) and Gill et al. (20), the sigmoid colon can be retracted cephalad with a stitch passed through an appendix epiploicae and brought out directly through the anterior abdominal wall and skin. Using electrosurgical endos-hears a transverse peritoneotomy along the inferior peritoneal fold is created at the level of the second inferior peritoneal fold to reach the vas deferens and seminal vesicles. The vas deferens is cauterized or clipped and transected. At this point, the surgeon must be aware of the deferential artery that runs posterior along to the ductus and close to the seminal vesicle. This artery should be selectively coagulated and divided. Dissection and cephalad traction of the vas allows access to the ipsilateral seminal vesicles, which is mobilized circumferentially. The tip of the seminal vesicle, supplied by the vesicular artery, is located in close proximity to the neurovascular bundle. Excessive electro-cautery in this area should be avoided in case of nerve-sparing technique.

TABLE 6 ■ Laparoscopic Radical Prostatectomy with the Montsouris Technique-Technical Steps of the Procedure

The more superior of these peritoneal folds represents the approximate location of the ureters and should be avoided. The more inferior fold, nearly at the depth of the peritoneal reflection, is created by the meeting of the vasa deferentia in the midline, with the seminal vesicles lying just lateral.

1. Posterior dissection of the prostate: Vas deferens and seminal vesicle dissection

Opening Denonvilliers'fascia

2. Anterior approach: Development of space of Retzius

Incision of endopelvic fascia

Ligation of the dorsal venous complex of Santorini 3. Bladder neck transection

4. Dissection of the lateral surfaces of the prostate

5. Apical dissection of the prostate Section of the venous complex

Incision of the urethra

Incision of the rectourethral muscle

6. Urethrovesical anastomosis

7. Eat from the abdominal cavity

A transverse peritoneotomy along the inferior fold is created at the retrovesical cul-de-sac to reach the vas deferens and seminal vesicles, which are mobilized following their arteries selectively coagulated and divided.

The Denonvilliers' fascia is horizontally incised to expose the prerectal fatty tissue and to allow rectoprostatic cleavage to be extended downward until the levator ani muscles are reached.

After making an inverted U-shaped incision, the urachus was divided. An avascular plane is developed on either side of the bladder and dissection is continued anterior and caudal as far as pubic bone.

After the prostate is retracted to the contralateral and placing the ipsilateral endopelvic fascia on stretch, the fascia is incised on its line of reflection.

After placement of back flow stitch, the dorsal vein complex is double-sutured with grasping of the needle in a 100-degree angle to the branches of the needle holder.

After incising, the fibrous fasica dissection is continued by following the detrusor muscle fibers where there is an avascular plane between the prostate and bladder until exposing the balloon of Foley catheter.

The lateral pedicle then is meticulously and slowly divided close to the lateral border of the prostate using clip application and cold cutting.

Incision of venous complex is performed by first coagulating with bipolar forceps and then incising tangentially to avoid incision of the anterior surface of the prostate.

The anterolateral urethral wall is incised with a cold knife or scissors. After the tip of urethral metal bougie is delivered through the anterior urethrotomy for exposing the posterior wall, the posterior wall of the urethra is incised similarly.

With gentle traction to the prostate superior, rectourethral muscle appears as the final attachment of the prostate and is then incised.

Four sutures are placed at 4,8,2, and 10 o'clock positions and tied outside the lumen.

Incisions are left open and a Drain introduced into the pelvis.

Opening Denonvilliers' Fascia

An important part of the posterior dissection represents the incision of Denonvilliers' fascia, which facilitates the dissection of the prostatic pedicles by taking the rectum away from the pedicles after bladder neck incision. To make the exposure easier, the bilateral completely mobilized seminal vesicles and vas deferens are retracted anteriorly and rectum is retracted posteriorly, thereby placing Denonvilliers' fascia on tension. A shallow incision is made and visualization of yellow perirectal fat confirms to entry into the correct plane between prostate and the rectum.

Step 2: Anterior Approach: Bladder Dissection

Development of Space of Retzius

Bladder dissection starts with an inverted U-shaped incision, lateral to the bladder contour but medial to medial umbilical ligament, which is extended inferior to the vas and superior to the abdominal wall. The horizontal part of the U-incision is located high on the undersurface of the anterior abdominal wall, cephalad to the dome of the bladder. An avascular plane is developed on either side of the bladder and dissection is continued anterior and caudal as far as pubic bone. At the end of this step, in the mid-line in the vicinity of the puboprostatic ligaments, a small pad of fat remains including superficial dorsal vein, which is thoroughly coagulated with bipolar electrocautery and transected.

After incision of endopelvic fascia, the dorsal venous complex of Santorini is ligated in the above-described way, similar to the Heilbronn technique following a back bleeding stitch placed across the anterior surface of the prostate using a similar needle. The tails of the back bleeding stitch are cut somewhat long because this suture is helpful during subsequent dissection at the bladder neck, as a locking grasping forceps can be fixed to the tags emanating from the suture knot that allows upward traction of the stitch later during the procedure.

Step 3: Bladder Neck Transection

The bladder is retracted cephalad holding from the long end of back flow stitch, thereby placing the anterior bladder neck on traction. To identify the bladder neck the anterior prevesical fat is retracted superior causing a faint outline of the prostatic vesical plane. After incising the fibrous fasica, dissection is continued by following the detrusor muscle fibers where there is an avascular plane between the prostate and bladder. The anterior wall is incised to expose the balloon of Foley catheter. The catheter balloon is deflated and catheter is pulled up into the abdomen to expose the lateral and posterior urethral walls, which are incised. The bladder neck is carefully preserved with the ureteral orifices far from region of dissection. The anterior layer of Denonvilliers' fascia is incised to enter the previously dissected retrovesical plane. The ductus deferens and seminal vesicles now are delivered through this opening and placed on anterior traction. The remainder of the attachments between the bladder and prostate are divided with electrocautery, maintaining hemostasis. The endpoint of the dissection bilaterally is the lateral pedicle of the prostate, which is anatomically identified by presence of yellowish perivesical fat.

Step 4: Dissection of the Lateral Surfaces of the Prostate

In the antegrade laparoscopic procedure the pedicles are exposed before being incised. A thin fat plane separates the prostatic vascular pedicles from the posterolat-eral neurovascular bundles. The pedicle is characterized by well-visualized arteries and veins.

At this stage of the technique, different strategies are performed depending on nonnerve-sparing versus nerve-sparing procedures.

Nonnerve Sparing

Bipolar coagulation, harmonic scalpel, or vascular clips (i.e., Hem-O-Lok clips) can be employed to transect the lateral pedicles widely. The ipsilateral seminal vesicle and duc-tus deferens are retracted anteriorly, placing the adjacent lateral pedicle on traction. Vascular clips or even an endo is consecutively placed across the lateral pedicle, away from and cephalad to the base of the prostate. After employing the clips or stapler, the lateral border of the prostate and neurovascular bundle from the perirectal fat is detached, thereby achieving a wide margin of excision. A similar maneuver is performed on the contralateral side, leaving the prostate attached only at the apex.

An avascular plane of dissection separating the urethra from the venous complex must be found underneath the venous complex. This plane allows complete identification of the prostate limits and urethra.

Nerve Sparing

Nerve sparing is performed in an antegrade fashion. The ipsilateral seminal vesicle and ductus deferens are retracted anteriorly, placing the lateral pedicle on traction. The lateral pedicle then is meticulously and slowly divided close to the lateral border of the prostate using clip application and cold cutting. To avoid thermal damage to the neu-rovascular bundle, the surgeon should avoid use of bipolar electrocautery. After division of the cranial pedicles dissection enters a pericapsular fatty space, that contains the neu-rovascular bundles, which must be preserved by lateral incision of a thin visceral fascia that covers the peribundle fat lateral and medial incision of the lateral edges of Denonvilliers' fascia. These incisions expose the neurovascular bundles and capsular arteries lateral, rising vertically into the prostate that must be clipped with 5-mm metal clips without coagulation to decrease the risk of thermal lesions. Dissection must be extended to the point where the bundles enter the pelvic muscular floor, which is pos-terolateral from the urethra.

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