BENIGN PROSTATE SURGERY III PERINEAL
The perineal prostatectomy is an uncommon approach for the surgical treatment of benign prostatic hyperplasia (BPH) but has several advantages over other “open” approaches. The operation is excellent for the removal of very large glands and permits complete removal of all adenomatous tissue. Anatomically, the perineal region varies less dramatically with body habitus than does the lower abdominal region, reducing operative times. Patients with prior renal transplantation or mesh inguinal hernia repairs in which the retropubic space may be scarred or obliterated are particularly well suited for this approach. Drainage of fluid after the procedure is “dependent” in that infected urine or exudate drains away from the operative area and is not retained within a cavity. Also, bleeding can be controlled under direct vision. Finally, morbidity and convalescence are low and minimal, respectively, with the perineal approach.
On the other hand, the perineal prostatectomy is technically more
difficult than other open approaches, making an accurate knowledge of perineal
structures important to avoid injury to the rectal wall or external sphincter
muscle. In addition, the operation is not suitable for extremely obese patients
or those with limited hip motion because of severe ankylosis of the hip or
spine or those with unstable artificial hips that would limit the need for
exaggerated lithotomy positioning required for the procedure. Common
degenerative disc disease is not a contraindication for perineal prostatectomy.
BENIGN PROSTATE SURGERY III PERINEAL |
With the patient in high lithotomy position, a perineal incision is made
in the shape of an inverted “U” with the apex 3 cm anterior to the anus. The
ischiorectal fossae on each side of the central tendon are opened and developed
bluntly with the index finger. The musculofibrous central tendon is divided,
exposing the anterior rectal wall, which, with the rectal sphincter, falls
backward and away from the superficial transverse perineal muscles. With gentle
dorsal traction on the rectum, the rectal wall is then detached from the
prostatic apex by dividing the rectourethralis muscle. Caution is needed with
this maneuver to avoid rectal injury. The prostate is then delivered into the
field and further cephalad separation of the prostate from the rectum is
undertaken with blunt digital dissection until the entire posterior surface of
the prostate is exposed, if necessary to beyond the ends of the seminal
vesicles.
After exposure of the posterior prostate, a transverse incision is made
across the center of the prostatic capsule and into the prostatic urethra
halfway between the apex and base of the prostate. The incision in the prostate
in this location is made directly into the compressed posterior zone tissue
of prostate to expose the adenoma. The lower lip of the incision through the
capsule is reflected backward, exposing the hyperplastic adenoma and the
urethral floor. A Young retractor is inserted through the opening in the
capsule, to provide counterpressure that elevates the adenoma into the wound.
The index finger is then inserted into the cleavage plane between the adenoma
and the surgical (false) capsule and the two lateral lobes and any median lobe
are easily enucleated. Enucleation performed with care
leaves the bladder neck intact. After hemostasis is achieved in the
prostatic fossa, a Foley catheter is inserted into the bladder and the balloon
inflated within the fossa. As with other “open” surgical approaches, if the
adenoma is unusually large, excessive bleeding may occur. In such cases the
bladder neck can be pulled down and the prostatic capsular vessels can be
ligated under direct vision. The prostatic capsule is then tightly closed with
a continuous or interrupted absorbable suture. A rubber
Penrose drain is usually placed on one side of the perineum and placed near the
sutured prostatic capsule. The skin is closed with interrupted suture. Most
capsules sutured in this manner will heal in 5 to 7 days, at which time the
urethral catheter is removed. Although not commonly used for the benign
prostatic enlargement, the perineal approach is a well-established and
frequently used approach for the treatment of prostate cancer (radical perineal prostatectomy).