Apical Dissection

Following division of the Santorini plexus, both neurovascular bundles are exposed lateral to the rectum by blunt dissection.

The approach to the apex of the prostate is determined by a decision to proceed with nerve-sparing or with the nonnerve-sparing technique.

The criteria for carrying out nerve-sparing technique are listed in Table 3.

Nonnerve-Sparing Technique

After transection of the dorsal vein complex, the anterior striated sphincteric urethral complex is demonstrated. The fibers of this complex at the apex are horseshoe shaped and

TABLE3 ■ Criteria for Carrying Out Nerve Sparing

Clinical stage

Role in nerve-sparing

T1

When prostate-specific antigen is relatively low and the number of positive biopsies or

the extent of biopsy involvement is limited

T2a

A contralateral nerve-sparing procedure can be proposed

T2b

A nerve-sparing attempt can result in positive surgical margins and give rise to

local failure

The dissection of the urethra should be performed as near as possible to the apex of the prostate before incision is carried out.

Because the apex of the prostate and rectal ampulla are in close proximity, rectal injuries during radical laparoscopic prostatectomy commonly occur at this location.

We avoid the use of bipolar or monopolar coagulation in the bundles area.

form a tubular, striated sphincter surrounding the membranous urethra (18). The urethral sphincter is incised using bipolar forceps and endoscissor exposing the smooth muscle of the urethra. Under the gentle cranial traction of the prostate, anterior rotation of the apex of the prostate occurs and the prostatourethral junction is illustrated where the anterior wall of urethra is incised sharply (no electrocoagulation). The anterior wall of urethra is incised at the level of the prostatic apex (i.e., veru montanum), trying to preserve a maximal length of the stump. After urethra transection the Foley catheter is ligated at the ure-thral meatus, cut and pulled inside the abdomen to achieve retraction of the gland cranially, using grasping forceps (VI Trocar). The 20-French bougie is inserted to facilitate the cutting of the urethral posterior wall. It is important not to divide the rectourethralis muscle, which fixates the urethral stump dorsally. The prostate apex is dissected gently from the rectum and the distal prostatic pedicles are clipped using 10-mm Hem-O-Lok clips.

Because, the verumontanum is considered as the beginning of the distal continence zone, the urethral transection should be performed at or just distal to the veru. Sometimes the apical prostate overlaps the urethra beyond the verumontanum with urethral transection at or beyond the apex, and the patient can expect a period of incontinence that exceeds what could be achieved if the transection had been made just distal to the verumontanum (17).

The dissection of the urethra should be performed as near as possible to the apex of the prostate before incision is carried out. The Foley catheter is ligated at the urethral meatus cut and pulled inside the abdomen to achieve retraction of the gland cranially, using a grasper (sixth port). The 20-French bougie is placed to assist in the division of the posterior urethral wall. This maneuver is facilitated by the use of 120-degree endodis-sector to retract the prostate (Fig. 6).

Because the apex of the prostate and rectal ampulla are in close proximity, rectal injuries during radical laparoscopic prostatectomy commonly occur at this location.

The apex of the prostate is dissected gently from the rectum using right angle forceps and suction device. The neurovascular bundle areas are clipped using 10-mm Hem-O-Lok clips and incised, releasing the posterolateral attachments of the prostate, while the midline is dissected bluntly.

Nerve-Sparing Technique

The nerves are microscopic in size; their anatomic location can be estimated by using the capsular vessels as a landmark. The neurovascular bundles are located in the postero-lateral side of the prostate, inside a triangle formed by the lateral pelvic fascia (lateral wall), prostatic fascia (medial wall), and the anterior layer of the Denonvilliers' fascia (base) (19). Near the apex, the neurovascular bundle travels at 5 and 7 o'clock positions. The lateral pelvic fascia is incised prior to the incision of the urethra. Displacing the prostate on its side exposes the lateral surface of the prostate. A right angle clamp is inserted under the lateral pelvic fascia beginning at the bladder neck extending distal towards the apex of the prostate, detaching the area of neurovascular bundle from the posterolateral border of the prostate and dissecting gently from the apical part of the prostate. All the prostatic branches from the neurovascular bundle are controlled step by step using 5-mm titanium clips. We avoid the use of bipolar or monopolar coagulation in the bundles area.

The urethra is incised as in nonnerve-sparing technique but when the striated sphincter is divided closer to the apex of the prostate, there is risk that the neurovascu-lar bundle may be damaged. As the neurovascular bundle approaches the apex of the prostate, it is often fixed medially beneath the striated sphincter by an apical vessel. For this reason, the lateral edges of the sphincter should be divided only down to the lateral edge of the smooth muscle of the urethra and not any further posteriorly (not close to the apex of the prostate) (18).

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