benign prostatic hyperplasia library notes

7/27/2019 Benign Prostatic Hyperplasia Library Notes

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Benign Prostatic Hyperplasia

BPH is a clinical diagnosis describing urinary symptoms attributable to obstruction by the prostate,

although some patients with BPH have minimally enlarged glands, and some with large prostates have

no symptoms. The symptoms of BPH are urinary frequency, urgency, hesitancy, slow stream, and/or

nocturia. These symptoms are not specific and may be caused by infection, urethral strictures, orneurologic dysfunction from diabetes, Parkinsons disease, multiple sclerosis, stroke, or spinal cord

injury. Besides voiding symptoms, consequences of BPH include. Over time, incomplete emptying may

lead to chronic bladder overdistension that can result in a, sometimes permanently.

Medical treatment of BPH is usually the first step. Alpha blockers act on alpha receptors in the smooth

muscle of the prostate and decrease its tone. 5-Reductase inhibitors, which block the conversion of

testosterone to the more potent dihydrotestosterone, shrink the prostate over several months. Both are

used either singly or in combination as medical therapy for BPH. If medications are ineffective at

alleviating urinary symptoms or other consequences of BPH, surgical intervention is indicated.

Transurethral resection of the prostate is the mainstay of endoscopic surgical BPH treatment. It is

extremely effective at improving flow and decreasing residual urine. Complications are rare but include

incontinence and excessive fluid absorption of the hypotonic irrigating solution used during resection,

resulting in the transurethral resection syndrome. It is due to hyponatremia and fluid overload, and

although rare, can result in death. Mental status changes and pulmonary edema are managed by

diuresis and sodium supplementation with hypertonic saline in severe cases. Because of these rare, but

potentially dangerous side effects, laser vaporization of the prostate has grown popular. It is associated

with very limited fluid absorption, and saline can be used because there is no electrocautery. There also

is less bleeding. Urinary outcomes appear to be similar to transurethral resection of the prostate.43

When the prostate is very enlarged (>100 g), endoscopic management is less effective and open surgical

procedures can be used. Suprapubic (simple) prostatectomy involves enucleation of the majority of the

prostate, but the capsule is left so there is minimal effect on continence and erectile function.

Benign Prostatic Hyperplasia

Essentials of Diagnosis

Prostatism: nocturia, hesitancy, slow stream, terminal dribbling, frequency.

Residual urine.

Acute urinary retention.

Uremia in advanced cases.


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General Considerations

The cause of benign prostatic enlargement is not known but is probably related to hormonal factors. The

mechanism for opening and funneling the vesical neck at the time of voiding is altered by hyperplasia of

the prostate, which causes increased outflow resistance. Consequently, a higher intravesical pressure is

required to accomplish voiding, causing hypertrophy of the vesical and trigonal muscles. This may leadto the development of bladder diverticulaoutpocketings of vesical mucosa between the detrusor

muscle bundles. Hypertrophy of the trigone causes excessive stress on the intravesical ureter, producing

functional obstruction and resulting in hydroureteronephrosis in late cases. Stagnation of urine can lead

to infection; the onset of cystitis exacerbates the obstructive symptoms. The periurethral and

subtrigonal prostate enlargement produces the most significant obstruction.

The prostate in young men has an anatomic capsule like an apple peel. In men with prostatic

enlargement, there is a thick surgical capsule similar to an orange peel, composed of peripherally

compressed true prostatic tissue (peripheral zone). The hyperplastic benign periurethral glands

correspond to the transition zone and are the cause of the obstruction (Figure 389)

Clinical Findings

SYMPTOMS AND SIGNS

Typically, the patient has lower urinary tract symptoms and notices hesitancy and loss of force and

caliber of the stream. The urgent need to void when the bladder is nearly full may be an early sign. He

may also be awakened by the urge to void several times at night (nocturia). Postvoid dribbling (terminaldribbling) is particularly disturbing. The complication of infection increases the degree of obstructive

symptoms and is often associated with burning on urination. Acute urinary retention may supervene.

This is associated with severe urgency, suprapubic pain, and a distended, palpable bladder.

The size of the prostate rectally is not of primary diagnostic importance, since there is a poor correlation

between the size of the gland and the degree of symptoms and amount of residual urine. The American

Urological Association (AUA) developed a 7-item, self-administered questionnaire (AUA symptom score)

that can assist the patient and physician in evaluating the patients lower urinary tract symptoms.

LABORATORY FINDINGS

Urinalysis may reveal evidence of infection. Residual urine is commonly increased (> 50 cc), and a timed

urinary flow rate is decreased (< 1015 cc/s). The serum creatinine may be elevated in cases with

prolonged severe obstruction.


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IMAGING STUDIES

Excretory urograms are often normal and not diagnostic and are thus not required. In late-stage cases,

the study may show hydroureteronephrosis if severe obstruction is present. This almost always resolves

after prostatectomy. The enlarged gland may cause an indentation in the inferior surface of the bladder,

which may result in a J-hook deformity of the distal ureter. The postvoiding film may reveal varying

amounts of residual urine. Renal ultrasound examination may obviate the need for urograms; however,

imaging is not required to make the diagnosis or to determine the need for or method of treatment.

Pelvic ultrasound in the office setting accurately predicts the amount of residual urine and thus obviates

bladder catheterization.

CYSTOSCOPIC EXAMINATION

Bladder cystoscopy reveals secondary vesical changes (eg, trabeculation) and enlargement of the

periurethral prostatic glands; however, cystoscopy is not required to make the diagnosis. It may identify

other conditions such as bladder stones or tumors in selected cases.

URODYNAMIC STUDIES

Simultaneous physiologic monitoring of bladder filling and emptying, urethral sphincter activity,

abdominal pressure, and pelvic floor muscle activity (electromyography) can be extremely useful in

documenting whether bladder outlet obstruction, poor bladder function, or other causes are

responsible for lower urinary tract symptoms. While urodynamic studies are not required for diagnosis

in all cases, they are helpful in cases with large postvoid residual volumes or underlying neurologic

disease to help determine appropriate management.

Differential Diagnosis

Neuropathic bladder may produce a similar syndrome. A history suggesting a neuropathic difficulty, such

as diabetes mellitus, stroke, or spinal cord injury or compression, may be obtained. Neurologic deficit

involving S2-4 is particularly significant.

Cancer of the prostate also causes symptoms of vesical neck obstruction. Serum prostate-specific

antigen may be elevated in patients with benign prostatic hypertrophy, and the level increases as the

volume of the prostate increases. Thus, an absolute value is not diagnostic, but in general, if it is over 10

ng/mL, the possibility of cancer should be evaluated.


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Acute prostatitis may cause symptoms of obstruction, but the patient is septic and has infected urine.

The prostate is exquisitely tender.

Urethral stricture diminishes the caliber of the urinary stream. There is usually a history of gonorrhea or

local trauma. A retrograde urethrogram shows the stenotic area. A stricture blocks the passage of an

instrument or catheter.

Treatment

The indications for operative management are impairment of or threat to renal function andbothersome symptoms. Because the degree of obstruction progresses slowly in most patients,

conservative treatment may be adequate. Drugs that relax the prostatic capsule and internal sphincter

(-adrenergic blocking agents) or decrease the volume of the prostate (5-reductase inhibitors or

antiandrogens) have been tried with considerable success.

CONSERVATIVE MEASURES

Treatment of chronic prostatitis may reduce symptoms. The resolution of a complicating cystitis usually

affords some relief. In order to protect vesical tone, the patient should be cautioned to void as soon asthe urge develops. Forcing fluids over a short time causes rapid vesical filling and decreasing vesical tone;

this is a common cause of sudden acute urinary retention and thus should be avoided. Patients with

urinary obstructive symptoms should avoid the use of cold remedies, including antihistamines, because

they are also a common cause of urinary retention. These conservative measures are of only temporary

helpif anyin patients with prostatic hyperplasia. There has been recent great interest, particularly by

patients, in the use of phytotherapy for treatment of lower urinary tract symptoms, including saw

palmetto, pumpkin seeds, and other plant extracts. Despite the claim of efficacy, however, adequate

scientific studies have not been done.

Controversy surrounds choices in the treatment of benign prostatic hyperplasia. No treatment (watchful

waiting) may be appropriate in patients who complain of mild to moderate symptoms and thus have low

AUA symptom scores and residual urine less than 70 cc to 100 cc. Interest has also focused on

nonoperative medical therapy for those with more significant symptoms. -Adrenergic blocking agents

relax the internal (bladder neck) sphincter and prostatic capsule. Selective agents that are long-acting

and preferentially work for this purpose include doxazosin and tamsulosin. 5-Reductase inhibitors


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block conversion of testosterone to dihydrotestosterone (the androgen active in promoting prostate

growth) and are useful for large glands, particularly in combination with an alpha-blocker, which has

been shown to best prevent urinary retention and other common progressive symptoms of prostatic

obstruction.

Catheterization is mandatory for acute urinary retention. Spontaneous voiding may return, but a

catheter should be left indwelling for 3 days while detrusor tone returns. If this fails, treatment is

indicated.

SURGICAL MEASURES

There are four classic approaches used in prostatectomy: transurethral, retropubic, suprapubic, and

perineal. The transurethral route is preferred in patients with glands weighing under 50 g to 70 g

because morbidity rates are lower and the hospital stay is shorter. Larger glands may require open

surgery, depending on the preference and experience of the urologist. The death rate is low in each

procedure (12%). Potency is at greatest risk when the transperineal exposure is used, but impotence

occasionally results following transurethral resection of the prostate.

An alternative approach to the treatment of benign prostatic hyperplasia is transurethral incision of the

prostate. This procedure consists of incision of the prostate at the bladder neck up to the

verumontanum, allowing expansion of the entire prostatic urethra. It is especially effective when the

primary point of obstruction is caused by a median bar or high posterior lip of the bladder neckwithout lateral lobe obstruction.

Additional alternative treatments are transurethral vaporization, laser prostatectomy, transurethral

microwave thermotherapy, transurethral needle ablation, and high-intensity focused ultrasound

ablation of the prostate. Laser prostatectomy seems to have the most promise at present, and recent

data suggest that Holmium and KTP (potassium titanyl phosphate) laser may have nearly the same

efficacy as transurethral resection of prostate, with less morbidity. However, long-term results of

randomized trials are pending.

Prognosis

Most patients with marked symptoms receive considerable relief and substantial improvement in urine

flow following surgical treatment; however, those with milder forms may benefit from drug therapy.


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Embryogenesis and Congenital Anomalies

The prostate gland is formed around the end of the third month (first trimester) from the epithelium of

the future prostatic urethra. The epithelium proliferates and penetrates the surrounding mesenchyme,

which is the future fibromuscular prostatic tissue.

Surgical Anatomy

Topographic Anatomy and Relations

The classical description of the adult prostate is that it has the size, shape, and consistency of a large

chestnut. The form of the prostate is that of a compressed inverted cone: pyramidal, having a base and

an apex. It is located between the vesical neck of the bladder and the apex of the urogenital diaphragm.

According to Wilson et al.,74 the prostate apex is located above the ischial tuberosities in 99.3% of cases.

This fact may help the radiologist-oncologist to deliver accurate external beam radiation.

The normal weight of the prostate in a young adult is from 17 to 19 g. The numbers 4, 3, 2 are useful as

a mnemonic for remembering the transverse, vertical, and sagittal dimensions in centimeters,

respectively, of the gland.

The prostate is enveloped by extraperitoneal connective tissues that cover the thin anatomic capsule(true capsule) of the organ, and it in turn envelops the proximal male urethra.

Fixation and Suspension

The following structures are responsible for the fixation of the prostate in its bed:

Puboprostatic ligaments

Urogenital diaphragm

Bladder


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Prostatic sheath

Fascia of Denonvilliers

Steiner75 stated that the puboprostatic ligaments have a pyramidal shape that is part of a larger

urethral suspensory mechanism which attaches the membranous urethra to the pubic bone (Fig 25-21).

Both males and females have a similar mechanism of suspension formed by 3 anatomic entities in

continuity.

A condensation of the endopelvic fascia between the prostate and the levator ani forms the white

line (Fig. 25-22). This band attaches posteriorly to the ischial spine, where it is continuous with the

transverse fascial septum formed by the fascia of Denonvilliers. Anteriorly, the arcus tendineus of the

fascia pelvis attaches to the pubic bone approximately 1 cm from the lower edge of the pubis about a

centimeter lateral to the symphysis. This band is intimately continuous with the puboprostatic and

pubourethral ligaments on either side of the midline. The puboprostatic ligaments connect the pubic

bone with the capsule of the gland.

The fascial capsule (true capsule) of the prostate is continuous with the superior fascia of the

urogenital diaphragm, the anterior thickened edge of which forms the transverse perineal ligament.

The intermediate pubourethral ligament is formed by the pubic arcuate and the transverse perineal

ligaments.

Steiner75 stated that the attachment of the urethral suspensory mechanism is inserted bilaterally into

the lateral urethral border, forming a sling from the pubic arch. A good anatomic understanding of the

relationship of the urethral suspensory mechanism to the urethra and its striated muscle sphincter and

dorsal vein may facilitate apical dissection during radical retropubic prostatectomy. Proper prostatic

apical dissection will minimize bleeding, ensure positive surgical margins, and reduce the likelihood of

urinary incontinence.


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Prostatic Urethra

The prostatic urethra (Fig. 25-23) begins at the urethral meatus at the apex of the trigone of the bladder.

This opening is crescent-shaped, invaginated posteriorly by a protuberance caused by the underlying

glandular tissue (median lobe of the prostate), thus forming the uvula vesicae. This is continuous with a

posterior midline urethral ridge, or crest, in the urethra. The urethral ridge has a distinctly expanded

portion called the verumontanum, or seminal colliculus. To better understand these structures, we can

define some of the anatomic entities related to the prostate and the urethra (see also the discussion of

the prostatic urethra in the male urethra section of this chapter).

The urethral crest is a ridge located on the floor of the posterior urethra between the bladder and the

membranous urethra. It is wider at the vesical neck (the uvula) than on its pathway to the membranous

urethra.

The verumontanum (colliculus seminalis) is a small elevated hillock at the middle area of the urethral

crest.

The prostatic utricle or uterus masculinus is a crypt located in the middle portion of the verumontanum,

approximately 6 mm deep. Garat et al.76 and Varlet et al.77 reported congenital dilatation of the utricle.

Meisheri et al.78 urge that patients with an enlarged prostatic utricle be carefully examined to ascertain

whether this condition is associated with female internal organs.

The orifices of the ejaculatory ducts are located on the right and left sides of the verumontanum.

The prostatic sinus is a depression located on the right or left side of the urethral crest, home of the

openings of the prostatic ductules and the urethral glands.

Ureteric ectopia occurs most commonly in the prostatic urethra, and in the seminal vesicle with less

frequency. If an ectopic ureter is in the seminal vesicle, a normal ipsilateral kidney is uncommon.

Prostatic Surfaces


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There are four prostatic surfaces: one posterior, one anterior, and two inferolateral.

The posterior surface is flat transversely and convex vertically. It is separated from the rectal ampulla by

the bilaminar fascia of Denonvilliers. This surface is characterized by a midline groove that is wider

toward the base of the gland, and serves to partially separate the gland posteriorly into left and right

lobes.

The posterior surface may be palpated by digital rectal examination. The vesicoprostatic junction is

located at the upper border of the posterior surface.

The narrow and convex anterior surface is located between the apex and the base. Multiple large veins

separate this surface from the symphysis pubis. According to Tanagho,71 the distance between the

pubic symphysis and the anterior surface is approximately 2 cm.

The avascular puboprostatic ligaments are fibrous cords, wide or narrow. They connect the upper limits

of the anterior surface of the prostate to the pubic bone, at the right and left sides of the cartilaginous

area.

The right and left inferolateral surfaces are embraced by the anterior part of the levator ani muscles.They are fixed to the levator by the arcus tendineus of the fascia pelvis (white line), sagittal connective

tissue bands between the ischial spine, and the pubic bone (Fig. 25-22). Here there is a very rich venous

network and fibrous tissue which contributes part of the lateral prostatic sheath.

The levator prostatae muscle is the most anterior and most medial part of the levator ani muscle. These

muscle fibers pass about the prostate gland and insert into the perineal body beneath the prostate

gland, related to the anterior parts of the levator ani muscle. Thus, the muscle encroaches upon the

prostate behind by a U-shaped sling (Fig. 25-22). Last79 astutely noted that levator prostate is not an

apt term. We tend to agree; nonetheless, at orgasm, the pubococcygeus muscle contracts strongly and

with this, the prostatic portion probably does, indeed, both lift and compress the prostate gland.

Fascia of Denonvilliers


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In early fetal peritoneal development, the peritoneum extends downward as a pouch reaching the

muscular pelvic floor and perineal body. Later the pouch disappears as the growing organs lift the

peritoneal covering, resulting in fusion of the more anterior and posterior parts of the peritoneal

covering, producing a bilaminar transverse septum. This septum is continuous with the peritoneum

above and the perineal body below, and is continuous between the ischial spines. Layers unite with each

other, forming a potential space. The union of these two layers produces the fascia of Denonvilliers.

Van Ophoven and Roth80 concluded: Denonvilliers fascia consists of a single layer arising from fusion

of the 2 walls of the embryologic peritoneal cul-de-sac. Histologically, it has a double-layered quality.

The fascia of Denonvilliers extends from the deepest point of the interprostatorectal peritoneal pouch

to the pelvic floor. A so-called posterior layer is in reality the rectal fascia propria.

The potential space which was present embryologically between the two laminae discussed above maybe retained as the space of Proust (Fig. 25-24). It has a strong anterior layer related to the prostate and

a loose posterior layer related to the rectum. Jewett et al.81 were not able to demonstrate the plane of

cleavage of the potential space within the two layers of the Denonvilliers fascia. It is more likely that the

so-called posterior layer is in fact part of the lateral pillar of the rectum.

Structure

Lowsley82 reported that the prostate gland can be divided into six lobes: anterior, posterior, median,

subcervical, right lateral, and left lateral (Fig. 25-25). His description is no longer accepted, however,because it was based on studies of fetal and newborn prostates, and is not an accurate description of

the adult gland

Avoiding use of the term lobes because of the confusion it engenders, McNeal83-85 described four

regions or zones in the prostate: peripheral, central, transition, and anterior fibromuscular stroma (Fig.

25-26). The urethra is the key anatomic entity defining these regions (Figs. 25-26, 25-27, 25-28, 25-29,

25-30, 25-31, and 25-32). Posterior to the urethra is the glandular area. Anterior to the urethra is the

fibromuscular area; that is, the ventral portion of the glandular prostatic tissue is covered by the

fibromuscular stroma.

To describe the prostate, McNeal uses three reference planes (Fig. 25-27): sagittal, coronal, and oblique

coronal.


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The sagittal plane bisects the prostate and incises the full length of the urethra, demonstrating its

lumen. The urethra is thus the key anatomic entity related to all four of McNeals zones.

The coronal section shows both the distal urethra and the ejaculatory ducts in continuity with one

another; that is, the ducts are parallel with the distal urethra.

Theoblique coronal plane passes along the long axis of the proximal urethral segment, which cannot

be seen in the coronal plane. It has an upward pathway through the bladder neck, transecting the base

of the verumontanum.

McNeal84 wrote that marked histologic differences exist between the peripheral and central zones,

suggesting important differences in biologic function. This information and some of the other findings

from McNeals brilliant embryologic, anatomic, histologic, and pathologic observations aresummarized

below.

The 4 Zones of Mcneal from an Embryologic, Anatomic, Histologic, and Pathologic Viewpoint

Wendell-Smith86 has summarized the structural and functional description of the prostate used in the

1998 edition of the Terminologia Anatomica,87 which blends the concepts of McNeal with findings ofother workers on predilection for pathology and malignancy:

The use of the term lobe is confined to the right and left lobes and the variable middle lobe. The term

lobule is used for the subdivisions, which are named from the anatomical position. Thus each side has a

superomedial, an anteromedial, an inferoposterior, and an inferolateral lobule. Also necessary to

describe a site of predilection is a peri-urethral gland zone. In ultrasound diagnosis, the trapezoid area is

important: its upper limit is the rectoperinealis, its anterior limit is the intermediate part of the urethra,

its lower limit is the anoperinealis, and its posterior limit is the anorectal junction. Confusion at the

bladder neck is resolved by recognizing that the position of the internal urethral orifice varies with

functional state of the bladder: when it is filling the orifice lies above the base of the prostate; when

voiding begins, the orifice descends to the base of the prostate; between the filling internal orifice and

the emptying internal orifice is the bladder neck part of the urethra.

We recommend Wendell-Smith's comprehensive article to the interested student.


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Hricak et al.88 studied the normal anatomy of the prostate by MRI. They reported that zones were seen

very well. Cornud et al.89 used endorectal MRI to study the zonal anatomy of the prostate. They

reported clearly delineated anatomic boundaries of the transition zone, the prostatic capsule, the

neurovascular bundles, and the caudal junction of the ejaculatory ducts.

Some workers believe that approximately 70-80% of prostatic cancers may develop in the peripheral

zone. Cancer may develop in the central zone at a rate of only 5-10%. Remember: when a nodule forms,

it can be palpated by rectal digital examination. Benign prostatic hyperplasia may appear lobar by digital

examination, although the normal, nonhyperplastic prostate lacks lobar configuration.90

Reese et al.91 suggested that the central zone of the prostate may be the selective site of origin of

proteolytic enzymes in seminal fluids.

Capsules of the Prostate

There are three capsules of the prostate; two (the true and false) are anatomic (Fig. 25-33), the third is

pathologic (Fig. 25-34).

The true capsule is a very thin covering surrounding the gland in toto.

The false capsule (periprostatic fascia or prostatic sheath) is an extraperitoneal fascia (visceral layer of

endopelvic fascia). This capsule is continuous with 4 fasciae:

Anterior: fascia of the bladder, puboprostatic ligament

Lateral: arcus tendineus of the fascia pelvis

Posterior: fascia of Denonvilliers


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Inferior: superior fascia of the urogenital diaphragm

Between the true and false capsules is a venous plexus, the prostatic or pudendal venous plexus (Fig. 25-

33).

Part of the normal aging process is progressive prostatic growth due to benign prostatic hyperplasia

(BPH). The peripheral part of the prostate becomes compressed against the surrounding endopelvic

connective tissue, forming a surgical capsule (pathologic capsule). When enucleation of the prostate is

performed, the plane between the compressed peripheral tissue and the adenomatous tissue permits

removal of the adenoma, leaving behind the peripheral condensed prostatic tissue and the anatomic

capsule.

The pathologic capsule is formed of essentially normal prostatic tissue peripheral to an adenoma,

compressed against the false capsule (Fig. 25-34B). This remains after enucleation of the adenoma (Fig.

25-34C).

DiLollo et al.92 studied the morphology of the prostatic capsule and its posterosuperior region. They

advised the following:

[I]n the prostatic zone limited by the ejaculatory ducts, the ventral surface of the seminal vesicles and

the basal portion of the urinary bladder, there is no real connective tissue barrier around the prostate;

on the contrary, a rich vascular network is present. Thus, a malignant tumor which begins in this zone

should be considered from the very early stages potentially extracapsular. It is important to note that

the present conclusions confirm the earlier observations of Denonvilliers.

Vascular Supply

Arteries

According to Clegg,67 there are three arterial zones within the prostatic parenchyma: anterior or

capsular, intermediate, and urethral.


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Characteristically, the urethral vessels enter the prostatovesical junction at 7 to 11 oclock and at 1 to 5

oclock. The two sides have few anastomoses.

The blood supply of the prostate is derived primarily from the inferior vesical artery (Fig. 25-35). A

branch of this artery enters the prostate laterally at the prostatovesical junction. This artery divides into

two branches, the peripheral and the central. The peripheral branch serves the majority of the prostatic

parenchyma; the central branch supplies the urethra and the periurethral tissues.

Other arteries contributing rami to the prostate are the internal pudendal and middle rectal arteries.

Last79 considered the middle rectal artery to be poorly named, since most of its blood goes to the

prostate gland.

Remember that an accessory pudendal artery may arise in the pelvis and pass under the pubic arch with

the deep dorsal vein to reach the penis. Such arteries usually arise from a branch of the anterior division

of the internal iliac artery. Accessory pudendal arteries can arise unilaterally or bilaterally from the

obturator artery, the internal pudendal artery prior to its exit from the pelvis, or directly from the

internal iliac or the superior and inferior vesical arteries. The accessory pudendal artery leaves the pelvis

by passing through the hiatus between the pubic arcuate ligament and the transverse perineal ligament.

An accessory pudendal artery may provide the dorsal artery of the penis, the deep artery to the corpus

cavernosum, or both. Such branches are divided during radical prostatectomy. Their frequency of

occurrence is only about 3% in females, but 10% in males.93 This artery is always present in lower

animals, and is called the urogenital artery, because it supplies the bladder.94,95

Veins

There is a rich venous plexus (prostatic plexus) (Fig. 25-36) between the prostate gland and the prostatic

sheath. It communicates with the internal iliac venous system and the presacral veins. The prostatic

venous plexus receives the deep dorsal penile vein and the veins of the base of the bladder. The vesicaland internal iliac veins receive most of the venous blood.

It has been said that the prostatic venous plexus does not have any valves. Part of the blood drains

toward the extradural venous plexus of Batson;96 this suggests an explanation for the metastasis of

cancer of the prostate to the spine and skull.


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Editorial Comment The concept that the propensity for prostatic cancers to metastasize to the skull and

the spine may be related to an absence of valves in the venous drainage of the prostate and the

drainage of prostatic blood toward the extradural venous plexus of Batson96 is time honored. It is a

possible mechanism for cancer cells to reach these tissues, but cancer cells could also pass through thepulmonary circulation or the lymphatic circulation. For hematogenous metastases cells must first enter

into the venous system (or pass through the lymphatic system into the venous system). Once the cancer

cells arrive at a potential metastatic site the actual development of a metastasis is probably a rare event.

Establishment of a metastasis is dependant upon a viable cell or cells attaching to the vascular

endothelium, then traversing the endothelium, then being able to start to proliferate in the

environment, and then eventually being able to provoke the host tissue into providing a tumor blood

supply (angiogenesis). I believe that the propensity for hematogenous metastases to develop at a

particular site is far more dependent on the interplay of the complex cell surface molecules and cellular

messengers than on any vascular interconnections. (Roger S. Foster, Jr., MD)

The deep dorsal vein of the penis reaches the prostatic venous plexus by passing through the cleft

between the pubic arcuate ligament and the transverse perineal ligament of the urogenital diaphragm.

According to Redman,97 the vein trifurcates upon emerging through the opening, with a pathway

toward the anterior lateral parts of the prostate, thereby forming Santorinis plexus. In the laboratory,

we have seen low bifurcation. In cases of uncontrolled bleeding from the dorsal venous plexus during

radical retropubic prostatectomy, the deep dorsal vein of the penis can be ligated.

Lymphatics

From the prostatic acinus, large intraprostatic trunks are formed. These penetrate the prostatic capsule

and form the periprostatic lymphatic plexus. This plexus yields lymphatic vessels which follow the

vascular network of the prostatovesical arteries.

The lymph vessels that follow the prostatovesical arteries travel to the internal iliac lymph nodes (Fig.

25-37). The vessels also travel to the presacral lymph nodes and, occasionally, to the external iliac lymph

nodes.

Hinman66 emphasized that from a surgical standpoint, the primary sites of lymphatic drainage of the

prostate are the obturator and external iliac nodes. He also stated that the presacral and presciatic

nodes are less important as initial sites of prostatic lymphatic drainage. Hinman also mentioned the

work of Whitmore and Mackenzie,98 McLaughlin et al.,99 and Wilson et al.100


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The histologic studies of the glandular prostate by Fukuda et al.101 demonstrated a high lymphatic

density in the midbase region surrounding ejaculatory ducts. The authors concluded that the midbase

region might be a route of lymphatic spread of prostate cancer.

Metastasis to other anatomic entities such as the penis102 may occur.

Innervation

The preganglionic sympathetic nerve supply to the smooth muscle of the seminal vesicles, ejaculatory

ducts, and prostate gland arises in the intermediate gray area of spinal cord levels L1 and L2 (or L3).

Postganglionic fibers arise in the preaortic or pelvic plexuses. The sympathetic fibers cause contraction

of the smooth muscle and expulsion of seminal fluid.

Parasympathetic fibers from sacral cord levels S2, S3, and S4 synapse in pelvic ganglia and periprostatic

ganglia. They act perhaps to dilate blood vessels and stimulate secretion from glands of the genital

system, including the prostate.

The neurovascular bundles described by Walsh and Donker103 are located on the dorsolateral surface

of the prostate gland between the rectal wall and the prostate (Fig. 25-38). They are concealed withinthe periprostatic fascia. These nerve plexuses include branches of the preganglionic parasympathetic

visceral efferent fibers (nervi erigentes or pelvic splanchnic nerves with cell bodies in the

intermediolateral cell column of S2-S4), sensory fibers, and sympathetic fibers. Although these nerves

are very small, their anatomic location can be estimated by looking for the capsular vessels. Preserve the

neurovascular bundles during nerve sparing radical retropubic prostatectomy by avoiding tissues that

are located posterolaterally. This may prevent impotence. Klotz104 advocates intraoperative cavernous

nerve stimulation during radical prostatectomy to optimizing nerve sparing since these nerves are often

difficult to visualize and may have a variable course.

Carlton105 stated that visualization of the neurovascular bundle is better with perineal prostatectomy

than with retropubic prostatectomy. The neurovascular bundle may be saved during prostate surgery by

rotating the bladder and elevating the ureter, with close division of the tissues around the wall of the

urinary bladder.


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We quote Baskin et al.106:

Perforating branches from the dorsal lateral neurovascular bundle do not exist based on serial step

sectioning and microscopic examination of male genital specimens. Surgically it is possible to elevate the

neurovascular bundle but the dissection needs to remain directly on top of the tunica albuginea to

prevent neuronal injury. Small perforating branches into the urethral spongiosum may be injured with

unknown significance. We continue to advocate plication in the nerve-free zone at the 12 o'clock

position for correction of penile curvature.

It has become evident that four factors are involved in maintaining erectile function following radical

prostatectomy: preservation of the neurovascular bundle, tumor category, age, and preservation of

accessory pudendal arteries. Of these factors, preservation of the neurovascular bundle appears to be

most important. Catalona and Basler107 reported potency rates of 63% and 41% of patients undergoingbilateral and unilateral nerve-sparing radical prostatectomy, respectively. Investigators from Stanford

University108 report less favorable results: that the ability to achieve unassisted intercourse with

vaginal penetration occurred in 1.1% of men having non-nerve sparing radical prostatectomy, 13.3%

with unilateral neurovascular bundle preservation, and 31.9% with bilateral neurovascular bundle

preservation. Quinlan and associates109 noted that advancing tumor categories and age result in lower

potency rates. Polascik and Walsh110 have discovered that when present, preservation of the accessory

pudendal artery significantly increases potency rates among men undergoing radical prostatectomy.

For patients with clinically localized prostate cancer, Ghavamian and Zincke111 advocate nerve

dissection starting at the lateral aspect of the prostate with secondary urethral dissection to decrease

dissection around the striated sphincter.

Histology

Seventy percent of the weight of the prostatic mass is glandular epithelium. Thirty percent is

fibromuscular, mainly non-striated. The glandular part contains ducts and acini which are lined with

columnar epithelium and drain in the posterior and lateral walls of the prostatic urethra.

According to McNeal,84,85 the three glandular regions of the prostate differ histologically and

biologically. In all regions, ducts and acini are lined with secretory epithelium, with a layer of basal cells

and interspersed endocrine-paracrine cells beneath. The peripheral zone has small, rounded, uniform

glands. The central and transitional zones have very large and irregular acini.


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Perhaps autocrine, paracrine, endocrine (androgen-sensitive or androgen-insensitive), and other

unknown factors play a role in the regulation and control of the growth of the prostate. Therefore,

growth as well as metastasis of prostatic carcinomas may be controlled or altered by the above factors.

Enzyme-histologic studies of Zaviacic112 support the belief that the prostate and the urethral and

paraurethral glands in the female are homologous.

Physiology

The prostate gland secretes a milklike alkaline fluid. This fluid is very important for the fertilization of the

ovum, since sperm within both the ductus deferens and vaginal tissue produce fertilization-inhibiting

acidity. Guyton113 stated that prostatic fluid most likely neutralizes the acidity of the fluids of the

ductus deferens and vagina after ejaculation, enhancing the motility and fertility of the sperm. The

prostatic fluid also contains citric acid, calcium, phosphorus, and other substances.

We quote Hayward and Cunha114:

The development of the prostate is controlled by steroid hormones that in turn induce and maintain a

complex and little understood cross talk between the various cell types making up the gland. The resultof this intracellular communication can be either new growth or growth quiescence, depending upon

the differentiation state of the cell type being stimulated. Secretory function of the prostate is

dependent upon direct stimulation of fully differentiated prostatic epithelial cells by androgens. The

prostate thus seems to be regulated in a similar manner to other organs of the male and female genital

tract with proliferative control mediated by cell-cell interactions, whereas differentiated function is

determined by direct steroid action on the parenchymal cells.

Surgical Applications

Remember Healey and Hodges115 axiom about the space of Proust: It has been the lament of many

that it is not always easy to find this passage between wind and water.

The prostate will hypertrophy after middle age, causing partial or total obstruction of the prostatic

urethra.


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The thick fibromuscular parenchyma anterior to the urethra forms the anterior third of the prostate. It

may undergo fibromuscular hypertrophy, but not glandular hypertrophy.

The transition zone lateralto the preprostatic sphincter is probably responsible for the origin of all

prostatic hyperplasias, but almost never for malignancy.

The peripheral zone is the site most commonly responsible for the formation of malignant nodules.

The urogenital sinus is most likely responsible for the embryogenesis of the peripheral and transition

zones, as well as of the periurethral glands.71 The wolffian duct appears to be responsible for thegenesis of the central zone, and thus may be a factor in the resistance of this zone to the formation of

cancer.

McNeal116 stated:

Cancer originates from the peripheral and transition zones.

Benign nodular hyperplasia may also develop in these two zones.

Cancers with a volume of more than 5 cc and poor differentiation are the most likely to metastasize.

Morphologically favorable cancers have a volume of less than 4 cc; unfavorable cancers have a volume

of more than 12 cc.

Metastasis to lymph nodes is strongly related to the size of the cancer and the percentage of high-

grade tumor.


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With enucleation, the urologists index finger is introduced between the benign prostatic mass and the

pathologic capsule. This avoids the prostatic venous plexus, which is external to this plane.

There are several approaches to the prostate gland:

Transurethral resection (TUR)

Transabdominal approach (through the urinary bladder)

Radical retropubic approach (through the space of Retzius)

Perineal approach

An excellent article by Carlin and Resnick117 provides detailed descriptions of the anatomic entities

related to radical perineal prostatectomy, from outside to deep, in order to integrate this knowledge

with the surgical approach to the radical perineal prostatectomy. The entities they describe are:

Skin

Subcutaneous tissues

Colles fascia

Superficial transverse perineus muscle (Fig. 25-39)

Deep transverse perineus muscle


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Central tendon (perineal body)

Pelvic floor musculature

Anorectum and external anal sphincter (Fig. 25-39)

Rectourethralis muscle (Fig. 25-40)

Denonvilliers fascia (Figs. 25-41, 25-42, 25-43, and 25-44)

Neurovascular bundle and neuroanatomy (Figs. 25-43, 25-45)

Vascular supply (Fig. 25-46)

In the perineal approach, with division of the central fibromuscular perineal body, the anterior and

posterior layers of the potential space of Proust should be identified. This serves not only to protect the

rectum, but also to avoid bleeding.

Remember that the lower rectal wall is heavily fixed to the apical part of the prostate and, therefore,

to the proximal urethra. The rectourethralis muscle might be responsible for this stout attachment. The

proximity of the peritoneum in the rectovesical fossa must be borne in mind when using the perineal

approach. This is the area where rectal perforation most commonly occurs during radical prostatectomy.

When peritoneum in the rectovesical area is inadvertently opened, it is easy to think that the rectum has

been perforated. Awareness of the anatomy will help in this situation.


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Koch118 reminds us that knowledge of the prostatic dorsal venous anatomy facilitates dissection of

the prostatic apex with little bleeding and with preservation of the rhabdosphincter, urethra, and

neurovascular bundles.

We are grateful toDr. P.C. Walsh, who allowed us to reprint verbatim the anatomy of radical

prostatectomy.119

Radical perineal prostatectomy was first developed at The Johns Hopkins Hospital in 1904 by Hugh

Hampton Young120 and the retropubic approach was introduced in 1947 by Terrance Millin.121

Although rad-ical prostatectomy provided excellent cancer control, it never gained widespread

popularity because of major side effects. Virtually all men who underwent radical prostatectomy were

impotent, many had significant urinary incontinence, and when performed via the retropubic approach,

excessive bleeding was common. With the introduction of external beam radiotherapy for the treatmentof prostate cancer, by 1970 radical prostatectomies were rarely performed.

Recognizing that there was no better way to cure organ confined disease than to remove the primary

organ, in 1974 I embarked on a series of anatomical studies in an attempt to understand the source for

this morbidity with the hope that it might be avoided. In retrospect, it became clear that impotence was

universal because the location of the autonomic innervation to the pelvic organs and the corpora

cavernosa was not known, incontinence was common because the anatomical understanding of the

sphincteric complex was incorrect, and excessive bleeding occurred because the anatomy of the dorsal

venous complex and Santorinis plexus was not charted. This deficit in the understanding of the peri-

prostatic anatomy can be traced to the use of adult cadavers, which were not ideal for these

investigations. The agents used for tissue fixation dissolve adipose tissue, thus obscuring normal tissue

planes and the pelvic viscera compress the pelvic organs into a thick pancake of tissue, making anato-

mical dissection difficult *T+hese problems were overcome by intra-operative anatomical dissections,

and the use of infant cadavers for anatomical studies.

Anatomy of the Dorsal Venous Complex

Fig. 25-47.

During radical retropubic prostatectomy, excessive bleeding was common because the large venous

complex that travels over the anterior surface of the urethra and prostate must be divided. This venous

complex is covered by a thick sheath of dense fascia, which obscures the anatomical location of the


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venous tributaries. Anatomical studies showed that the deep dorsal vein leaves the penis under Bucks

fascia between the corpora cavernosa and penetrates the urogenital diaphragm dividing into three

major branches: the superficial branch and the right and left lateral venous plexus.122 The superficial

branch lies outside the pelvic fascia but the common trunk and lateral venous plexuses are covered and

concealed by this fascia (Fig. 25-47). The lateral venous plexuses travel posterolaterally and

communicate freely with the pudendal, obturator, and vesicle plexus. These anatomical observations

made it possible to devise major alterations in the surgical technique that avoided excessive bleeding:

1. The endopelvic fascia was opened adjacent to the pelvic sidewall to avoid injury to the lateral venous

plexus.

2. The puboprostatic ligaments were divided with care not to injure the superficial branch of the dorsal

vein nor to enter the anterior prostatic fascia covering Santorinis plexus and the dorsal venous complex.

3. The common trunk of the dorsal vein over the urethra was isolated with a right angle clamp,

transected, and ligated, thus avoiding most of the major bleeding associated with this procedure. The

development of this technique made the operation safer and provided a relatively bloodless field which

made it possible to view the periprostatic anatomy in a way not possible previously. Shortly after this

technique was developed, a patient reported that he was fully potent after surgery. This patient

continues to do well 20 years postoperatively. Based on that experience, I questioned why any man was

impotent after radical prostatectomy. At this time it was believed that impotence after radical

prostatectomy was neurogenic in origin, and that it was caused by injury to the cavernous nerves that

traveled through the prostate. For this reason, it was assumed that impotence was a necessary

complication of a radical prostatectomy. From this one experience, I knew that was not true.

Autonomic Innervation of the Corpora Cavernosa

The autonomic innervation to the corpora cavernosa is derived from the pudendal nerve and the pelvic

plexus. The pudendal nerve provides both autonomic supply to the corpora cavernosa and sensorysupply to the skin. Because the pudendal nerve is not close to the operative field, and because sensation

is intact in impotent men after surgery, injury to the pudendal nerve could not be implicated. Rather, it

was assumed that injury to the pelvic plexus or its branches must be responsible. The pelvic plexus

provides autonomic innervation to all of the pelvic organs but, until the time of this work, the exact

location of the pelvic plexus and the branches to the corpora cavernosa in man was not known.


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In 1981 I had the opportunity to perform fetal dissections with Dr. Pieter Donker, Emeritus Professor of

Urology at Leiden University, The Netherlands. Dr. Donker identified the fetus as an ideal model for

these studies because the fibrofatty tissue was less abundant, the pelvic structures were not disturbed

by the pressure of the abdominal viscera, and the nerves were correspondingly larger in relationship toadjacent structures. At the time that I met Dr. Donker, he was performing dissections of the pelvic

plexus to characterize the autonomic innervation to the bladder. After informing him that the branches

of the pelvic plexus to the corpora cavernosa were also not known, we traced these pathways in

stillborn male infants. The pelvic plexus, which provides autonomic innervation to all of the organs, rests

on the lateral surface of the rectum. The branches that innervate the corpora cavernosa were seen

clearly outside the capsule of the prostate and its surrounding tissue as they travel between the

prostate and rectum before penetrating the urogenital diaphragm and innervating the corpora

cavernosa103This study showed clearly that the prostate could be removed completely with

preservation of these nerves. This study provided the schematic anatomy of the pelvic plexus and

cavernous nerves. Next, landmarks in the adult needed to be developed.

In the operating room, it became clear that the capsular arteries and veins of the prostate were located

in the same region as the cavernous branches. This finding suggested that these vessels may serve as

the scaffolding for these microscopic nerves and that the neurovascular bundle could be used as a visual

landmark for their identification. To confirm this impression, an adult cadaver was perfused completely

with Bouins solution shortly after death. The pelvic organs were removed en bloc, 10,000 whole-mount

step sections were prepared, and a 3-dimensional reconstruction performed.123 This 3-dimensional

reconstruction showed clearly that the cavernous nerves did travel in association with the capsular

arteries and veins of the prostate outside the capsule and fascia of the prostate. Armed with these

findings, we characterized the full neuroanatomy of the male pelvis using dissections performed in fresh

cadavers.124 This study showed that the pelvic plexus is located 5-11 cm from the anal verge traveling

on the lateral surface of the rectum with its midpoint at the tip of the seminal vesicle. After providing

branches to the bladder, lower ureter, and prostate, the branches from the pelvic plexus travel in

association with the capsular arteries and veins of the prostate dorso-lateral to the prostate, where the

nerves exit to innervate the corpora cavernosa.

Anatomy of the Striated Sphincter Continence Mechanism

Fig. 25-48.

For years it was widely believed that the urinary continence mechanism in man was composed of a

group of horizontally oriented pelvic floor muscles contained in the levator ani complex. However, in


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1980 Oelrich showed that the sphincteric complex responsible for passive urinary control was a

vertically oriented tubular sheath.125 In utero, this sphincter extends without interruption from the

bladder to the perineal membrane. As the prostate develops from the urethra, it invades the sphincter

muscle thinning the overlying parts and causing a reduction or atrophy of some of the muscle. In the

adult, at the apex of the prostate the fibers are circular and form a tubular striated sphincter

surrounding the membranous urethra (Fig. 25-48). Thus, as Myers and colleagues have shown, the

prostate does not rest atop a flat transverse urogenital diaphragm like an apple on a shelf with no

striated muscle proximal to the apex.126 Rather, the external striated sphincter is more tubular and has

broad attachments over the fascia of the prostate near the apex. This anatomy had important

implications in transection of the dorsal vein complex (which is intimately associated with the striated

sphincter), the apical dissection, and reconstruction of the urethra.127

Pelvic Fascia

The prostate is covered with two distinct and separate fascial layers: Denonvilliers fascia, which covers

the posterior surface of the prostate, and the lateral pelvic fascia, which covers the pelvic musculature.

This fascia has also been called the prostatic fascia. All of these fascial layers are intimately associated

with the dorsal vein complex, the neurovascular bundle, and the striated sphincter (Fig. 25-48). These

intimate relationships must be well understood in order for the surgeon to completely remove localized

prostate cancer.

Anatomic Complications

Transurethral Resection

Complications of transurethral resection include:

Bleeding from the prostate parenchyma or bladder neck

Injury of the bladder wall and prostatic capsule or intraperitoneal perforation into the space of Retzius

Urethral strictures at the membranous urethra, penoscrotal junction, or fossa navicularis


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Incontinence

Bleeding from the prostate parenchyma or bladder neck may occur with transurethral resection.

Catheter traction will usually stop bleeding, if electrocautery is not successful. According to Smith,128

the most common area for bleeding is the anterior bladder neck. The surgeon must visualize and inspect

the prostatic fossa thoroughly. Occasionally, exploration, complete enucleation of the adenoma, direct

fulguration/electrocautery and/or ligation may be necessary. The prostatic urethra as well as the

prostatic fossa may be compressed with a balloon catheter to stop bleeding, if necessary.

Another complication is injury of the bladder wall and prostatic capsule, or intraperitoneal perforation

into the space of Retzius. With intra- or extraperitoneal injury, laparotomy and repair should be

performed. Small extraperitoneal perforations usually respond to prolonged Foley catheter drainage.

Urethral strictures may form at the membranous urethra, the penoscrotal junction, or the fossa

navicularis. A soft and gentle technique is the only prophylactic measure against urethral strictures.

Incontinence may follow transurethral resection. There are two functional sphincters for urinary control.

One, the internal sphincter, is at the bladder neck; this is the sphincter typically damaged during

transurethral prostatectomy (TURP). Thus, after TURP, the patient is more reliant on the external

sphincter. The best method to prevent incontinence is to avoid damage to the external sphincter caused

by overzealous resection.

Anticholinergic treatment is used in dealing with incontinence resulting from sphincter damage;

urologists try anticholinergics because their use is simple. Alpha-receptor stimulators, such as Ornade,

are beneficial to some patients.

Transabdominal Approach

Complications of the transabdominal approach (through the urinary bladder) include:

Damage to the external sphincteric apparatus


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Injury to the posterior capsule with injury to the seminal vesicles

Bleeding at the bladder neck

To avoid damage to the external sphincteric mechanism, the surgeon must cut apical attachments very

carefully.

Inspect the prostatic fossa for bleeding or injury of the seminal vesicles. If injury to the seminal vesicles

is discovered, repair the posterior capsule and anastomose it to the bladder neck.

Bleeding at the bladder neck can be controlled by ligating bleeding points using figure of eight at 5 and 7

oclock with 2-0 absorbable sutures. If bleeding continues, a purse-string suture around the bladder neck

should be considered.

Radical Retropubic Approach

Complications of radical retropubic prostatectomy (through the space of Retzius) include:

Bleeding

Rectal injury

Ureteric injury

Obturator nerve injury

Impotence


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Bladder neck contracture

Incontinence

Venous bleeding is the most common intraoperative complication during radical retropubic

prostatectomy. The anatomic entities involved are the venous plexuses around the prostate and the

deep dorsal vein of the penis; these are referred to collectively as the dorsal venous complex. During

lymphadenectomy, any branch of the internal iliac vein can be involved.

To avoid venous bleeding

Incise the endopelvic fascia carefully under direct vision. Large veins may lie directly behind the

endopelvic fascia. These may be controlled with cautery or ligature.

Carefully ligate the dorsal venous complex.

Carefully divide the puboprostatic ligaments. Approach from lateral to medial. Blunt dissection

between the puboprostatic ligaments will almost always cause bleeding. When transecting the

puboprostatic ligaments, take care to avoid branches of the dorsal venous complex; these are located

immediately behind the ligaments.

After successful control of the previous elements, follow with careful exposure of the prostatic apex.

This cannot be accomplished unless the incision, ligation, and division described above have been

followed.

Epidural anesthesia may result in a regional hypotension which can decrease blood loss.

Walsh129 advises bulldog clamps to both hypogastric (internal iliac) arteries for reduction of blood flow

to the prostate. Beware of the artery to the seminal vesicle at the very tip of the seminal vesicle; it can

cause troublesome bleeding.


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Rectal injury is very rare (1% according to Borland and Walsh130). It most commonly occurs during

dissection of the apex of the prostate. This is where the prostatic fascia is most adherent to the rectal

fascia. Upward retraction of the prostate will tent the rectum; this can increase the risk of iatrogenic

injury to the rectum.

Close a rectal laceration in two layers. Interpose omentum between the rectum and the vesicourethral

anastomosis through a small peritoneal opening. Administer antibiotics during and after surgery, along

with copious irrigations. Rarely, it may be necessary to perform a diverting colostomy. However, if the

bowel has not been prepared, the surgeon must weigh that risk when deciding whether the colostomy is

appropriate.

Ureteric injury may occur after the lateral, anterior, and posterior surfaces of the prostate are free. Then

the prostate is attached only to the bladder. Administer indigo carmine to assist in identifying the

ureteric orifices. Incise the anterior bladder neck, and identify the orifices. Then, dissect the posterior

bladder neck from the prostate, seminal vesicles, and ampullae of the ducti deferentes. Ureteric

reimplantation is advised in instances of ureteric injury close to the trigone.

Division injury of the obturator nerve at the pelvic sidewall requires end-to-end re-anastomosis. Division

of the obturator nerve will be followed by paralysis of the adductor muscle group, the gracilis, and the

obturator externus. A sensory deficit will also be present along the medial part of the thigh.

Impotence is the result of excision of the neurovascular bundle (which was described previously with

the innervation of the prostate). According to Walsh,129 the father of nerve-sparing prostatectomy, A

number of factors may be responsible for postoperative impotence other than injury to the cavernous

nerves.

Bladder neck contracture (vesicourethral anastomotic stricture) can be avoided by good mucosa-to-mucosa apposition of the bladder neck and the urethra. Use six interrupted 2-0 absorbable sutures at 2,

5, 7, and 10 oclock.


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Incontinence can be prevented by avoiding injury to the muscles of the pelvic floor and by leaving as

much urethral length as possible. The surgeon should perform a good mucosa-to-mucosa vesicourethral

anastomosis. Use of alpha-adrenergic agonists, anticholinergics, etc, is recommended.

Steiner131 lists the anatomic components of the urethral sphincter complex whose preservation is

necessary for continence:

entire circumference of rhabdosphincter musculature

periurethral fascial investments (pubourethral ligaments anterolaterally and median fibrous raphe

posteriorly)

The innervation of the rhabdosphincter is preserved by way of the intrapelvic branch of the pudendal

nerve (somatic). The innervation of the mucosal and smooth muscle components is preserved by way of

the urethral branch of the inferior hypogastric plexus (autonomic).

Perineal Prostatectomy

Complications of the perineal approach to the prostate include:

Inability to identify the anterior rectal fascia and the pathway to the prostate and prostatic apex

Bleeding

Bladder neck injury and occlusion of ureteric orifices

Urinary perineal leakage

Stricture at the urethrovesical anastomosis


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Incontinence

Impotence

The inability to find the pathway to the prostate by failure to identify the anterior rectal fascia is a true

anatomic complication. Incise the central tendon very carefully. Avoid any injury to the bulbospongiosus

muscle, the penile bulb, or the membranous urethra. Divide the variably distinct rectourethralis muscle

without injury either to the rectal wall or the urethra.

Venous bleeding results from separation of the prostate from the bladder.

Avoid injury to the bladder neck by incising the posterior bladder neck transversely between 5 and 7

oclock, until the fascia enveloping the seminal vesicles can be identified. Care must be exercised during

reconstruction of the bladder neck to avoid injury of the ureteric orifices.

Urinary perineal leakage is a very benign complication, and will heal rapidly. A Foley catheter should be

positioned in the most dependent area of the urinary bladder.

In perineal prostatectomy, the complications of stricture at the urethrovesical anastomosis,

incontinence, and impotence are similar to the conditions mentioned previously.

Ahearn et al.132 reported two cases of transient lumbosacral polyradiculopathy after radical

prostatectomy.

benign prostatic hyperplasia library notes

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