Chapter 24 Urinary Bladder

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HISTORY

The anatomic and surgical history of the urinary bladder is shown in Table 24-1.

Table 24-1. Anatomic and Surgical History of the Bladder

Sushruta (ca. 600 BC) Described perineal approach for removal of bladder stone in Sushruta Samhita

Herophilus of

Chalcedon (ca. 335-

280 BC)

Advocated use of the perineal approach for bladder surgery. Well known lithologist.

Colot 1475 Advocated suprapubic approach to bladder stones

Lacuna 1551 Gave first definitive report of a bladder tumor

Marian 1552 Apprentice of Franciscus de Romanis. Published description of the apparatus major, an operation in which a

fluted probe was inserted into the urethra. The surgeon opened the bladder by cutting alongside the probe.

Franco 1561 First to remove stone by suprapubic approach

Covillard 1639 Reported first deliberate removal of a bladder tumor using perineal approach

Cheselden 1728 Premier lithotomist of his time. Reported brilliant results, with only 20 mortalities out of 213 patients.

Lieutaud 1742 First to give a clear description of the trigone of the bladder

John Hunter 1757 Compared renal and bladder calculi

Heister (1710-1779) Wrote textbooks illustrating urinary incontinence devices

Duncan 1805 Wrote first English language reference to an artificial bladder

Bozzini 1807 Developed first endoscope for looking into bladder

Amussat Civiale

d'Etiolles

1814 Employed transurethral instruments to fragment bladder calculi

Simon 1852 First description of diverting urine into bowel in patient with bladder exstrophy

Henle (1809-1885) Discovered external sphincter of the bladder

Billroth 1874 Described removal of bladder tumor using suprapubic approach

Nitze 1877 Developed first cystoscope, which he employed to remove bladder stones in over 150 patients

Bigelow 1878 Introduced transurethral lithrotrites used in litholapaxy

Emmet 1882 Great master and teacher of plastic surgery of the bladder and perineum

Hartwig; Leiter 1887 Independently, each placed an Edison electric lamp on the end of a Nitze cystoscope

Bardenheuer 1887 Performed first total cystectomy

Albarran y Dominguez

(1860-1912)

Described the subtrigonal glands of the bladder

Kilvington 1907 Proposed urinary bladder reinnervation using crossover nerve surgery

Beer 1908 Performed endoscopic fulguration of bladder tumors

Frazier & Mills 1912 Reported first technically successful nerve root crossing procedure for urinary bladder innervation

Chiasserini 1935 Developed and performed reinnervation surgery through anastomosis

Marshall, Marchetti, &

Krantz

1949 Described retropubic bladder suspension

Bricker 1950 Popularized ileal conduit cutaneous urinary diversion

Bogash 1959 First to use prosthetic bladder with ureteral valves

Peyrera 1959 Described needle suspension of bladder

Hopkinson &

Lightwood

1966 Used an anal plug electrode to stimulate pelvic musculature for micturition

Carlsson & Sundin 1967 Attempted reconstruction of nerve pathways to the bladder in patients with spina bifida and

1980 paraplegia

Pollitano 1973 Injected Teflon paste periurethrally to control incontinence



Pollitano 1973 Injected Teflon paste periurethrally to control incontinence

Turnbull et al. 1975 Modified Bricker's ileal conduit with loop stoma

Emmott et al. 1985

Kock et al. 1978 Used ileum in bladder replacement (hemi-Kock augmentation)

Hodges et al. 1980 Advocated transuretero-ureterostomy to bypass a diseased distal ureter

Mitrofanoff 1980 Performed appendicovesicostomy

Bloom et al. 1982 Advocated combining early cystectomy with radiation therapy for bladder cancer

Lutzeyer 1984 Inserted single-chambered silicone bladder in sheep

Rowland et al. 1987 Developed the Indiana pouch

Hall; Tolley et al. 1996 Combined radical transurethral resection of bladder tumors with systemic chemotherapy

Klevmark; Heslington 1997 Studied ambulatory urodynamics

History table compiled by David A. McClusky III and John E. Skandalakis.

References

Coptcoat MJ, Oliver RTD. The role of surgery in the multimodality treatment of bladder cancer. In: Oliver RTD, Coptcoat MJ (eds). Bladder

Cancer. Plainview NY: Cold Springs Harbor Laboratory Press, 1998, pp. 129-147.

Kaleli A, Ansell JS. The artificial bladder: a historical review. Urology 1984;24:423-428.

Kaufman JJ. History of surgical correction of male urinary incontinence. Urol Clin North Am 1978;5:265-278.

Mettler CC. History of Medicine. Mettler FA (ed.) Philadelphia: Blakiston, 1947.

Pyrah LN. John Hunter and after: renal calculi and cancer of the bladder. Ann R Coll Surg 1969;45:1-22.

Schmidt JE. Medical discoveries: Who and when. Springfield, IL: Charles C. Thomas, 1959.

Schmidt RA, Tanagho EA. Feasibility of controlled micturition through electric stimulation. Urol Int 1979;34:199-230.

Simon J. Ectopia vesicae (absence of the anterior walls of the bladder and pubic abdominal parietes); operation for directing the orifices of the

ureter into the rectum; temporary success; subsequent death; autopsy. Lancet 1852;2:568.

Skinner EC, Boyd SD. Urinary diversion, augmentation procedures, and urinary unidiversion. In: Whitehead ED (ed). Atlas of Surgical

Techniques in Urology. Philadelphia: Lippincott-Raven, 1998, pp. 57-124.

Vorstman B, Schlossber S, Kass L. Investigation on urinary bladder reinnervation: historical perspective and review. Urology 1987;30:89-96.

Wein AJ. Ambulatory bladder monitoring: is it an advance? J Urol 1998;160:2310-2311.

EMBRYOGENESIS

Normal Development

The cloaca, a cavity lined with endoderm, is an expansion of the terminal hindgut. It develops around the 4th or 5th week and receives

the allantois and the mesonephric ducts. The urorectal septum, a transverse ridge between the allantois and hindgut, divides the

cloaca into an anterior urogenital sinus and a posterior rectum.

The urogenital sinus is subdivided into three parts:1,2

Vesical (cranial) portion or urinary bladder. Continuous with the allantois.

Pelvic (middle) portion. Produces the prostatic and membranous portions of the urethra in the male and the membranous urethra in the

female.

Phallic (caudal) portion or definitive urogenital sinus. Separated from the exterior by the urogenital membranes. Forms the penile urethra in

the male and the vestibule of the vagina in the female.

The allantois constricts and forms the urachus. This passes from the apical end of the bladder to the umbilicus, forming the median

umbilical ligament.

The caudal ends of the mesonephric ducts and ureters form the trigone, a part of the bladder wall. Early in development, the mucosa

of the trigone is of mesodermal origin. Later, endodermal epithelium forms the mucosa of the trigone and the bladder.

The bladder is located in the abdomen in infants and children. It enters the pelvis major at age six and enters the true pelvis after

puberty.3,4

Congenital Anomalies

Congenital anomalies of the bladder are shown in Table 24-2. We will briefly consider malformations of the urachus and exstrophy of

the bladder.



the bladder.

Table 24-2. Anomalies of the Bladder and Urethra

Anomaly Prenatal Age

at Onset

First Appearance Sex Most

Affected

Relative

Frequency

Remarks

Agenesis of the

bladder

3rd week? At birth Female? Very rare Other genitourinary tract anomalies usually present

Urachal

anomalies:

Patent

urachus

9th week or

later

In infancy Male Very rare

Umbilical sinus 9th week or

later

At any age ? Rare Usually found only if infected

Vesical sinus 9th week or

later

None Equal Common

Urachal cyst 9th week or

later

At maturity Equal Common Small cysts may exist without symptoms

Duplication of

the bladder:

Bilateral 3rd week At birth Equal Very rare Usually with duplication of all hindgut derivatives

Frontal ? In childhood Female Very rare Redundancy of mucosa only

Hourglass ? At any age ? Very rare Questionably congenital

Diverticula of

the bladder

7th week In infancy and

childhood

? Rare Not to be confused with acquired diverticula in adult males

Extrophy of the

bladder

5th week Birth Male Very rare Associated with epispadias

Ectopic ureter 6th week In childhood Female Common Urinary incontinence in females; usually asymptomatic in

males; often associated with double ureter

Ureterocele 8th week 1st year of life Female Common Often associated with double ureter

Vesicoureteral

reflux

? Males - at birth;

females - at age 4 yr

Probably

female

Common Associated with urinary tract infection

Posterior

urethral valves

? In childhood Male Common

Aganglionic

bladder

9th week In childhood ? Rare With or without associated megacolon

Duplication of

the urethra:

Female ? At birth Female Very rare

Male 10-14 weeks At birth Male Rare Accessory urethra often hypospadiac

Source: Skandalakis JE, Gray SW (eds). Embryology for Surgeons, 2nd Ed. Baltimore: Williams & Wilkins, 1994; with permission.

Anomalies of the urachus include the presence of cysts, sinuses or fistulas, and patent urachus (Fig. 24-1). Persistence of the lumen is

more frequent in the lower part of the urachus, near the bladder. The lumen is continuous with the bladder cavity in 50 percent of

affected cases.5 It can enlarge to form a urachal sinus or cyst, but rarely forms a fistula. The term "urachal diverticulum" is commonly

used to describe urachal remnants connected to the bladder, with no connection to the skin/umbilicus.

Fig. 24-1.



Malformations of urachus. A. Urachal cysts. The most common site is in the superior end of the urachus just inferior to the umbilicus. B. Two

types of urachal sinus ("urachal diverticulum") are illustrated; one is continuous with the bladder, the other opens at the umbilicus. C. Patent

urachus or urachal fistula connecting the bladder and umbilicus. (Modified from Moore KL, Persaud TVN. The Developing Human (5th ed).

Philadelphia: WB Saunders, 1993; with permission.)

Exstrophy of the bladder (Fig. 24-2) occurs in 1 in 10,000 to 40,000 births4 and most frequently in males. The bladder opens out to the

exterior in the lower abdomen, and the posterior wall of the bladder protrudes. This exposes the trigone and ureteric openings.

Characteristics of exstrophy of the bladder include

Epispadias

Widely separated pubic bones

Separated scrotum/labia majora

Divided penis/clitoris

Lack of muscle and scant connective tissue over the bladder

Incomplete closure of lateral folds forming the anterior abdominal wall. This condition occurs because mesenchymal cells fail to migrate

between the ectoderm of the abdominal wall and the cloaca during the fourth week.

Shortened ureterovesical tunnels (frequently). These result in a high propensity for vesicoureteral reflux.

Fig. 24-2.



A, C, E. Normal stages in the development of the infraumbilical abdominal wall and the penis during the fourth to eighth weeks. Note that the

mesoderm and later muscle reinforce the ectoderm of the developing anterior abdominal wall. B, D, F. Probable stages in the development of

exstrophy of the bladder and epispadias. In B and D, note that the mesenchyme (embryonic connective tissue) fails to extend into the

anterior abdominal wall anterior to the urinary bladder. Also note that the genital tubercle is located in a more caudal position than usual and

that the urethral groove has formed on the dorsal surface of the penis. In F, the surface ectoderm and anterior wall of the bladder have

ruptured, resulting in exposure of the posterior wall of the bladder. Note that the musculature of the anterior abdominal wall is present on

each side of the defect. (From Moore KL, Persaud TVN. The Developing Human (6th ed). Philadelphia: WB Saunders, 1998; with permission.)

Since individual cases of complete duplication of the urogenital system in females are associated with different anomalies, corrective

surgical procedures depend on multiple anatomic variables.6

SURGICAL ANATOMY

Topography

The age and sex of the individual and the amount of urine within the urinary bladder are responsible for the position, relations, shape,

and size of this muscular, hollow, midline pelvic organ.

Age

The urinary bladder is abdominal at birth, positioned at the extraperitoneal area of the lower abdominal wall. Around the 5th or 6th year

of age the bladder gradually descends into the area of the true (minor) pelvis, positioning between the pubic bones anteriorly and the

vagina (in the female) or the rectum (in the male) posteriorly. For all practical purposes it is related to the pelvic diaphragm.

Empty and Full Bladder

The normal capacity of the adult bladder is approximately 300 ml to 500 ml, although it normally accommodates 250 ml to 300 ml before

micturition. The normal male first senses content of the bladder at 100 ml to 150 ml. Distension becomes distinctly uncomfortable in

the male when the volume is at about 350 ml to 400 ml. As maximum capacity is approached, involuntary micturition occurs. In the

female, the preceding numeric values are considerably less, because of the smaller size of the bladder and differences in the anatomy

of the urinary system. In infants and children, the bladder capacity in ounces can be calculated by adding the number 2 to the age.

The empty bladder (Fig. 24-3) is within the pelvis, but the full bladder extends up to the periumbilical area. In both states the bladder

is enveloped entirely by the vesical representation of the endopelvic fascia. This fascia consists of areolar, fibrous, and fatty tissues.

Fig. 24-3.



A. The empty urinary bladder. The prostate is being palpated per rectum. B. The full urinary bladder. The peritoneum is stripped away from

the anterior abdominal wall as the bladder fills; hence, access to a full bladder may be gained extraperitoneally. Rupture may be

intraperitoneal or extraperitoneal. Large arrow indicates the direction of the trochar. The lower small arrow points to the extraperitoneal

space; the upper small arrow points into the intraperitoneal space.

Relations

For descriptive purposes we present the empty bladder as having four surfaces, four ducts, and four angles or junctions (Fig. 24-4).

Fig. 24-4.

The four surfaces, four ducts, and four angles of the urinary bladder.

Surfaces

One superior

Two inferolateral



Two inferolateral

One inferoposterior

Ducts

Two ureters

One urachus

One urethra

Angles or junctions

One urachovesical junction (apex)

Two ureterovesical junctions

One urethrovesical junction (neck)

Each angle is associated with one of the ducts:

The anterior angle (apex) is related to the urachus (median umbilical fold)

The posterolateral angles are related to both ureters

The inferior angle (neck) is related to the urethra

The relations of the urinary bladder are detailed below.

Anterior. These consist of the symphysis pubis and pubic bones, separated from the bladder by the space of Retzius. The peritoneum covers

the superior surface (dome) and the upper part of the inferoposterior surface (fundus). When the bladder is full, it lifts the suprapubic

peritoneum away from the anterior abdominal wall.

Posterior. These include the seminal vesicles, ductus deferens, rectovesical space, prostatic fascia, rectum (in males), and anterior vaginal

wall and cervix (in females)

Lateral. These are the pubic bone, obturator internus (right and left), and levator ani muscles (just above the obturator internus).

Base. In the female the base of the urinary bladder is related to the anterior vaginal wall and to the cervix. Under normal conditions, the

fundus and body of the anteverted and anteflexed uterus rest upon the base and the superior surface of the bladder.

The clinician subdivides the urinary bladder as follows.

Base (posterior wall)

Lateral walls

Dome

Apex

Neck

Trigone

Remember

The apex is the meeting of the superior and inferolateral surfaces and the site of the beginning of the urachus.

The vesical neck is the anterior midline meeting point of the right and left inferolateral surfaces. It is attached to the pelvic diaphragm by the

fibromuscular pubovesical fascia which, in the female, is part of the pubovesicocervical fascia.



The body, or corpus, is the part of the urinary bladder between the fundus (posterior) and the apex (anterior).

Prevesical Space of Retzius and Ligaments of the Bladder

For all practical purposes, the space of Retzius, the so-called prevesical space, extends into both the abdomen and the pelvis, being a

division of the entire extraperitoneal space. The space of Retzius is situated in front and to the sides of the urinary bladder. Its

boundaries are listed below.

Anterior. Symphysis pubis

Lateral. Pubic bone, fascia of obturator internus muscle, superior fascia of levator ani muscle, lateral puboprostatic ligament

Medial. Inferior lateral surface of bladder

Superior. Peritoneum bridging the upper surface of the bladder and lateral pelvic wall

Posterior. Vascular stalk of the internal iliac artery and vein with their sheath. Sheath reaches posterolateral border of the bladder.

Inferior. Puboprostatic or pubovesical ligaments, reflection of the superior fascia of levator ani muscle to the urinary bladder from the arcus

tendineus fascia pelvis

Potentially, the space of Retzius is larger than the retropubic space. It extends upward and laterally to form a triangular space

between the medial umbilical ligaments (the obliterated umbilical arteries), with its apex at the umbilicus and its base provided by the

puboprostatic or pubovesical ligaments. The space is "a continuous bursa-like cleft in the areolar tissue at the sides and front of the

bladder which allows the bladder to fill and empty without hindrance."7

The space of Retzius is bounded behind by the vesicoumbilical fascia, a mantle of mixed connective tissue that extends upward from

the urinary bladder toward the umbilicus and posterolaterally as the lateral pillars of the bladder. The space of Retzius is continuous

above with the space of Bogros, the potential space between the extraperitoneal connective tissue and the transversalis fascia.

Therefore the space anterior to the urinary bladder (Fig. 24-5) contains connective tissue which is divided into two areas by the

umbilical prevesical fascia: 1) the retropubic space, which is anterior to the umbilical prevesical fascia and posterior to the lower

abdominal wall and symphysis pubis, and 2) the perivesical or preperitoneal space, which is located between the prevesical fascia and

the peritoneum that partially covers the urinary bladder.

Fig. 24-5.



Fascial spaces and laminae associated with the bladder, prostate, and rectum. The bladder is shown distended.

The peritoneum of the bladder has several folds attaching it to the pelvic wall (Fig. 24-6). These overlie condensations of connective

tissue, nerves, and vessels which are referred to as the "ligaments" or "pillars" of the bladder.

Fig. 24-6.

Diagram of the bladder and some of its ligaments. (Modified from Skandalakis LJ, Gadacz TR, Mansberger AR Jr, Mitchell WE Jr, Colborn GL,

Skandalakis JE. Modern Hernia Repair: The Embryological and Anatomical Basis of Surgery. New York: Parthenon, 1996; with permission.)



The concept of "true" and "false" ligaments has been with us for over a century. It refers to their apparent strength ("true") or

weakness ("false") as supports of the bladder. These terms are mostly of mnemonic value, and are listed in Table 24-3.

Table 24-3. Ligaments of the Bladder

Ligament Location

True ligaments

Median umbilical ligament (urachus) (unpaired) Dome of bladder to umbilicus

Lateral true ligament Lateral wall of bladder to tendinous arch of pelvic fascia

Medial umbilical ligament (obliterated umbilical arteries) Inguinal ligament

Medial puboprostatic ligament (male) Pelvic wall to prostate gland

Lateral puboprostatic ligament Pelvic wall to prostate gland

False ligaments

Superior false ligament (unpaired) Covers the urachus

Lateral false ligament Bladder to wall of pelvis

Lateral superior ligament Covers the medial umbilical ligament

Posterior ligament (sacrogenital fold) Side of bladder, around rectum to anterior aspect of sacrum

Source: Skandalakis LJ, Gadacz TR, Mansberger AR Jr, Mitchell WE Jr, Colborn GL, Skandalakis JE. Modern Hernia Repair: The Embryological and

Anatomical Basis of Surgery. New York: Parthenon, 1996; with permission.

Retrovesical Space

The boundaries of the retrovesical, or rectovesical, space in the male (Fig. 24-7A) are:

Anterior. Posterior surface of the bladder with vesical fascia, seminal vesicles, ducti deferentes, terminal ureteric segments, lateral true

ligament of the bladder

Superior. Peritoneum and transverse fold of bladder

Posterior. Anterior surface of the rectal ampulla with intervening prerectal fascia and rectovesical septum (fascial septum of Denonvilliers)

Inferior. Rectourethral ligament, pelvic diaphragm

Fig. 24-7.



A. The peritoneum of the male pelvis in paramedian section. B. The peritoneum of the female pelvis in paramedian section.

Both the vesical and rectal fasciae are loose connective tissue. Between them lies a stronger fascia, the bilaminar fascia of

Denonvilliers, with the so-called space of Proust between the two laminae. Thus the true retrovesical space lies between the vesical

fascia and the anterior layer of the rectovesical or rectoprostatic membrane (Denonvilliers' fascia) in the male.

The vesical plexuses are located posterolaterally on either side of the bladder. The retropubic space is located between the pubic

bones and symphysis pubis anteriorly and the bladder and vesical plexus (in its hypogastric sheath) posteriorly and posterolaterally.

Between the fundus of the urinary bladder and the rectum lie the following anatomic entities enveloped by the visceral fasciae of the

urinary bladder and the rectal ampulla (Figs. 24-7, 24-8):

Seminal vesicles

Terminal part of the bilateral ducti deferentes and their ampullae

Base of the prostate gland

Fig. 24-8.



The pelvic fascia of the male in median sagittal section. The rectourethralis consists of strands of smooth muscles.

In the female the boundaries of the retrovesical space (Fig. 24-7B) are:

Anterior. Posterior surface of the bladder with vesical fascia; the true lateral ligament of the bladder

Superior. Peritoneum

Posterior. Anterior surface of the vagina with anterior vaginal fascia or the pubocervical ligament

Inferior. Reflection of the posterior vesical fascia and anterior vaginal fascia; pelvic and urogenital diaphragms or the pubocervical ligament;

pelvic and urogenital diaphragms

Information about hernias of the prevesical and retrovesical spaces will be found in the chapter on the peritoneum, omenta, and

internal hernias.

Fixation of the Bladder

The following entities furnish the anatomic fixation of the bladder (see Fig. 24-6):

Median umbilical ligament (urachus)

Right and left medial umbilical ligaments (obliterated portions of the umbilical arteries)

Medial puboprostatic ligament

Lateral puboprostatic ligament

Lateral ligament (pillar) of the bladder

Bladder Wall

The wall of the urinary bladder is formed by four coats: serous, muscular, submucosal, and mucosal.

Serous coat. Covers the bladder partially as the peritoneum. The fibrous stroma also covers those parts of the bladder not covered by

peritoneum.

Muscular coat. This is the well known detrusor muscle. It is composed of smooth muscle, arranged in whorls and spirals in a single layer,

except in the area of the trigone and neck where two or three layers (inner longitudinal, middle circular, outer longitudinal) are described (Fig.

24-9).

Layer of submucosa. Demonstrable everywhere in the vesical wall except in the area of the trigone.

Mucosal coat. This thick coat lining the interior of the bladder is formed by several layers of transitional epithelium.

Fig. 24-9.



Structure of the bladder wall. (Modified from Hinman F Jr. Atlas of Urosurgical Anatomy. Philadelphia: WB Saunders, 1993; with permission.)

This combination of muscular architecture is responsible for the formation of the four following anatomic entities.

Interureteric ridge (or bar of Mercier) is formed between the right and left ureteric orifices at the interior of the urinary bladder, forming the

base, or the upper boundary of the trigone of the bladder.

Uvula, in men, is a projection into the posterior aspect of the internal urethral meatus at the apex of the vesical trigone, produced by the

underlying trigone musculature and the median lobe of the prostate gland.

Pubovesical muscles (right and left) are formed by muscular fibers arising anteriorly from the pubic bone.

Rectovesical muscles (right and left) are formed by muscular fibers interconnecting the bladder and the rectum.

From a surgical standpoint, however, the muscle of the bladder is singular, and should be considered as such in the operating room.

However, the reader should remember the structural and functional differences between the detrusor muscle and the musculature of

the vesical trigone. According to Tanagho,8 the bladder neck is formed by participation of the trigonal musculature, the detrusor

muscle, and the urethral musculature.

Elbadawi9 studied the pathology and pathophysiology of the detrusor in incontinence. Routine biopsy evaluation reveals its structural

morphology (smooth muscle, interstitium, and intrinsic nerves).

The detrusor is an involuntary smooth muscle under the control of the parasympathetic nervous system. We agree with Malvern10 that

the musculature of the detrusor is "both embryologically and histochemically separate from that of the urethra." There is also an

intrinsic innervation among the detrusor smooth muscle fibers.

Bates and colleagues11 were the first to use the term "detrusor instability" when discussing the so-called "urgency syndrome." This

condition presents with frequency of micturition, nocturia, urgency, and urge incontinence. Couillard and Webster12 presented a table

of etiological factors of this syndrome (Table 24-4).

Table 24-4. Suggested Etiologic Factors in the Hyperactive Bladder

Neurologic diseasedetrusor hyperreflexia

Detrusor instability

Congenital

Bladder outlet obstruction

Aging

Vesical neck patency, stress incontinence



Urethral instability

Psychosomatic

Source: Couillard DR, Webster GD. Detrusor instability. Urol Clin North Am 1995; 22:593-612; with permission.

According to Rivas and Chancellor,13 urodynamic testing should be used for accurate evaluation of normal and abnormal functions of

the urinary bladder and urethral sphincters.

Anatomy of the Trigone

The trigone is a smooth area within the base of the bladder. It is bounded by three orifices: the right and left ureterovesical orifices

and the internal urethral meatus at the neck of the bladder.

The trigone region is relatively indistensible. It is formed by two muscular layers superficial and deep located deep to the mucosa,

as reported by Tanagho and Pugh.14 This area is relatively smooth, even in the empty bladder (Fig. 24-10).

Fig. 24-10.

The normal uterovesical junction and trigone. A. Section of the bladder wall perpendicular to the ureteral hiatus shows the oblique passage

of the ureter through the detrusor and also shows the submucosal ureter with its detrusor backing. Waldeyer's sheath surrounds the

prevesical ureter and extends inward to become the deep trigone. B. Waldeyer's sheath continues in the bladder as the deep trigone, which

is fixed at the bladder neck. Smooth muscle of the ureter forms the superficial trigone and is anchored at the verumontanum. (Modified from

Brooks JD. Anatomy of the lower urinary tract and male genitalia. In: Walsh PC, Retik AB, Vaughan ED Jr, Wein AJ (eds). Campbell's Urology

(7th ed). Philadelphia: WB Saunders, 1998; with permission.)

The superficial layer of the trigone is formed by longitudinal fibers of the intravesical ureter at the ureterovesical orifice that spread

into the base of the urinary bladder. The final destination of some fibers is perhaps in the urethra or (in the male) in the ejaculatory



into the base of the urinary bladder. The final destination of some fibers is perhaps in the urethra or (in the male) in the ejaculatory

ducts, contributing to the formation of the crista urethralis. In the female, however, the termination of these fibers is at the external

meatus.

The deep layer of the vesical trigone, under the superficial trigone and above the detrusor muscle, is the continuation of the

fibromuscular tissue around the terminal part of the ureters (sheath of Waldeyer). The bladder outlet is surrounded by the middle layer

of the detrusor muscle deeply, and by the trigone superficially.

Tanagho,8 the scholar of the subject, reported that the superficial trigone can be dissected from the deep trigone. The deep trigone

can be separated from the detrusor muscle, at least in its upper half. He stated the following about the trigone, "The ureter has merely

changed from a tubular to a sheet-like form. One may say that the ureter does not end at the ureteral orifice but continues

uninterrupted as a flat sheet instead of a tubular structure."8

Vesical Neck

The sphincteric apparatus of the vesical neck is formed by the middle circular layer of the detrusor and the anterior longitudinal

bundles of the outer coat (Fig. 24-9B). However, according to Nergardh and Boreus15 and Klck,16 the non-striated muscle of the neck

is different from that of the detrusor. Therefore, the neck of the bladder probably acts as a separate functional entity. In the male,

smooth muscle forms a complete circular collar around the preprostatic portion of the urethra. This is the internal or proximal sphincter.

In the female child, striated fibers completely surround the urethra, according to Oelrich.17 In the adult, the sphincter muscle of the

urethra is thickest on its ventral aspect and thins as it passes to the dorsal side of the urethra. There appears to be a dorsal septum

or raphe into which the fibers insert. A variable number of fibers cross the midline. Some muscle fibers run obliquely and some proximal

fibers course vertically upward into the bladder musculature. This muscular coat is also infiltrated with smooth muscle fibers. Smooth

muscle bundles from the bladder overlie the proximal part of the urethral sphincter.

Remember

Striated muscle fibers form the external sphincter of the urethra. It is located within the urogenital diaphragm. Therefore it is distal to the

internal sphincter, which is formed by a mixture of striated and smooth muscle in the proximal urethra.

Geppert et al.18 reported that the obturator fascia and the internal obturator muscle may be used in a modified technique of

cystourethropexy for the elevation of the vesical neck.

Vascular Supply

Arteries

The blood supply of the urinary bladder is very rich and the collateral circulation is excellent. The arteries of the bladder are the

superior, middle and inferior vesical arteries. These originate from the anterior division of the internal iliac (hypogastric) artery. The

obturator and inferior gluteal arteries may contribute small branches (Fig. 24-11). When present (40%), aberrant obturator arteries

may contribute, variably (but in some cases by branches of significant caliber), to the vascular supply. In the female the uterine and

vaginal arteries also participate in the arterial blood supply of this organ.

Fig. 24-11.



The arterial supply of the bladder.

Veins

A rich network of veins, located deep to the adventitia, surrounds the urinary bladder. The network is drained by several veins which

empty into the internal iliac vein (Fig. 24-12). Variations are numerous.

Fig. 24-12.



The venous drainage of the bladder. (Modified from Hinman F Jr. Atlas of Urosurgical Anatomy. Philadelphia: WB Saunders, 1993; with

permission.)

Several plexuses drain into other venous networks in the space of Retzius. These networks include the plexus of Santorini

(prostatovesical or pudendal plexus). This plexus receives tributaries from the perineum, particularly from the shaft of the clitoris or the

penis, by way of the deep dorsal vein and the cavernous veins. These veins are not usually accompanied by arteries, except in the

presence of aberrant deep or dorsal arteries of the penis/clitoris.

Lymphatics

The bladder wall has three levels of lymphatic vessels: submucosal, muscular, and perivesical. All unite at the subadventitial area, then

drain to the external iliac nodes through three lymphatic networks, depending on their site of origin in the bladder.

The lymphatics of the base, neck, and trigone travel upward, anterior to the insertion of the ureter, and terminate in the internal,

external, and sacral nodes. The lymphatics of the anterior wall, together with prostatic lymphatics, terminate in the external iliac

nodes. Remember, the obturator nodes are usually the "landing site" for the prostate (cancer, etc.), and are the most important

clinically. The lymphatics of the posterior wall drain into the internal iliac nodes. In general, the lymphatic vessels follow the superior

and inferior vesical arteries.

Carcinoma of the urinary bladder will metastasize to the obturator, external iliac, and occasionally the sacral nodes.

Innervation

An excellent summary of the innervation of the urinary bladder was provided by de Groat19 :

The central nervous regulation of the lower urinary tract is mediated by simple on-off switching circuits in the brain and spinal

cord that are under voluntary control. Interruption of central inhibatory mechanisms can unmask primitive voiding reflexes that

trigger bladder hyperactivity.

The urinary bladder is innervated by neural fibers from the autonomic system (sympathetic system from T11 to L2, and

parasympathetic system from S2 to S4) as well as from somatic nerves, from S2, S3 and S4 (pudendal nerve) and by several other

routes not via the pudendal nerve.

Autonomic Nervous System

SYMPATHETIC

Preganglionic sympathetics arise from the intermediolateral cell column at T11-L2 or at L1 and L2 forming white communicating rami

which pass to the sympathetic trunk; from this the lumbar splanchnic nerves are formed. These nerves form several plexuses, such as

the superior hypogastric plexus, which is the lower part of the aortic plexus (Fig. 24-13). The superior hypogastric plexus produces the

right and left hypogastric nerves, which travel downward medial to the internal iliac artery and anterior to the sacral sympathetic

chain. They enter the right and left inferior pelvic hypogastric plexuses close to the base of the bladder, and are responsible for the

autonomic innervation of the superficial trigone musculature and the urethra.

Fig. 24-13.



The pelvic nerves and plexuses.

PARASYMPATHETIC

Preganglionic parasympathetic neurons arise in the intermediate gray of the spinal cord at S2, S3, and S4. These fibers leave the spinal



cord and enter the ventral primary rami of the spinal nerves at those levels. The preganglionic neurons leave the ventral primary rami

as the so-called pelvic splanchnic nerves (or nervi erigentes). The pelvic splanchnic nerves enter the right and left pelvic plexuses

(Fig. 24-13) and the preganglionic fibers ultimately synapse in ganglia in the pelvic connective tissues or upon, or within, the walls of

the pelvic organs, including the urinary bladder. Small islands of ganglionic cells and profuse nerve elements are distributed richly within

the bladder. Postganglionic parasympathetic fibers provide motor stimulation for the detrusor musculature of the bladder.

Sensory fibers for vesical distension and other sensory modalities are carried to the sacral part of the spinal cord by way of the pelvic

splanchnic nerves (Fig. 24-14). Sensory fibers for pain pass both by way of the pelvic splanchnic nerves, and by sympathetic

pathways up through the pelvic, hypogastric, and preaortic plexuses to reach the sympathetic chains. Here they exit to gain access to

the lower thoracic and upper lumbar segments of the cord. Because of the duality of the pathways for pain, presacral neurectomy

does not materially reduce vesical pain; rather, bilateral anterolateral cordotomy may be required to attain relief.

Fig. 24-14.



The nerve supply of the bladder and urethra.

Current thinking20-22 regarding pain arising from pelvic viscera is that it follows the parasympathetic fibers back to the central nervous

system (CNS) (S2-4) rather than following sympathetics, other than pain arising in the fundus of the uterus which is transmitted via

sensory fibers which traverse the superior hypogastric plexus. (Thus the rationale for presacral neurectomy as treatment for

dysmenorrhea.) Also, ovarian pain fibers accompany the arterial supply up to the origins of the gonadal arteries from the aorta; thus,

such pain can be relieved by transecting the infundibulopelvic ligament containing ovarian nerves, arteries, veins, and lymphatics.

Discussions of vesical pain in various references emphasize the parasympathetic pathways to the cord. In addition to the pelvic

viscera, the pain fibers of the lower respiratory tract pass to the CNS by way of parasympathetic paths; pelvic splanchnic nerves carry

pelvic pain and the vagi convey pain fibers of the lower respiratory tree.

Somatic Nerves

Somatic neurofibers arise from the sacral cord at S2, S3, S4 (Figs. 24-13 and 24-14) and leave the ventral primary rami of those spinal

nerves to form the pudendal nerve. This nerve is responsible for the innervation of the periurethral striated sphincteric apparatus that

voluntarily stops urination, including the compressor urethrae muscle and the sphincter urethrae of the urogenital diaphragm and the

bulbospongiosus muscle of the superficial perineal compartment. Unilateral sacrifice of sacral nerves results in little bladder or anorectal

dysfunction.23

We quote from Fowler:24

To effect both storage and voiding, connections between the pons and the sacral spinal cord must be intact as well as the

peripheral innervation which arises from the most caudal segments of the sacral cord. From there the peripheral innervation

passes through the cauda equina to the sacral plexus and via the pelvic and pudendal nerves to innervate the bladder and

sphincter. Thus, the innervation for physiological bladder control is extensive, requiring suprapontine inputs, intact spinal spinal

connections between the pons and the sacral cord, as well as intact peripheral nerves.

Remember

The neurophysiology of the lower urinary system is full of controversial and enigmatic speculations. It is not within the scope of this book to

offer these controversial details. We present only the anatomy and surgical applications of this area, not the pathophysiology.

The sympathetic nerves spring from the thoracolumbar portion of the spinal cord.

The parasympathetic nerves spring from the sacral portion of the spinal cord at levels S2, S3, and S4.

The male has two sphincteric networks. The proximal is at the bladder neck and is of smooth muscle origin. The distal is at the membranous

urethra and consists of both smooth and striated muscle. The action of both networks produces the continence mechanism.

In radical prostatectomy with removal of the bladder neck, the sphincteric apparatus of smooth muscle of the urethra may be able to control

incontinence. Also, contraction of the pelvic floor probably constricts the membranous urethra.25

The female has only one sphincteric network, at the bladder neck and proximal urethra, perhaps at the vesicourethral junction.

The proximal half of the urethra is above the pelvic floor. Therefore, abdominal pressure compresses this part of the urethra. The pelvic floor

relaxes voluntarily, producing a voluntary relaxation of the fibers of the external urethral sphincter.

Higher Level Representation

According to Waxman,26 micturation is mediated by the spinal cord, "but descending pathways from the brain modify, inhibit, or initiate

the reflexes" (Fig. 24-15). Cortical representation of the urinary bladder is most likely present in the paracentral lobule, whose

stimulation may evoke bladder contraction. Other higher levels may be present, but their identity and nature of participation are

obscure. Whether this system initiates relaxation or contraction of the external sphincter in starting or stopping micturition is not

known.



Fig. 24-15.

Descending pathway and innervation of the urinary bladder.

To initiate urination the person should be able to voluntarily relax the perineal muscles. The perineal muscles are:

Levator ani



Levator ani

Sphincter and compressor urethrae

Bulbospongiosus (in the male)

The following muscles initiate voluntary contraction after urination:

Ischiocavernosus

Bulbospongiosus

External sphincter

Remember

The sympathetic trunk may bifurcate or trifurcate as it descends through the abdomen and pelvis. Branches may descend in the psoas-

vertebral groove.

Afferent fibers within the pudendal nerve convey sensation from the external sphincter and the posterior urethra.

The internal sphincter is innervated by the autonomic nervous system. The external sphincter is supplied by the pudendal nerve, with

skeletal motor fibers arising from the ventral horn of cord levels S2-S3-S4.

In the male, the rarely paralyzed internal sphincter is continuous with the smooth muscle of the trigone and the ureteric muscle. It is

innervated by the sympathetic fibers from the hypogastric plexus. The external sphincter is innervated by the pudendal nerve

(voluntary action) and is rarely affected by disease. If it is divided by surgery, incontinence results.

In the female, for all practical purposes the internal sphincter is continuous with the compressor urethra and urethrovaginal sphincter

distally. These several muscular entities are inadequate to maintain urinary continence unless the bladder and urethra are supported.

Without proper angulation of the urethra, incontinence results.

Bladder dysfunction, failure of ejaculation, and impotence may result from injury to sympathetic and parasympathetic nerves during

separation of the posterior wall of the rectum from the sacrum. The scissors and the palm of the dissecting hand must stay close to the wall of

the rectum to avoid the nerves during mobilization of the anorectum.

In males with retroperitoneal lymphadenopathy or undergoing bilateral sympathectomy, one should remove the sympathetic ganglionic

segment at the L1 level only unilaterally. Clinically the left side is more important than the right side. Preserve the left if you can, and be more

careful with it. This procedure will avoid failure of ejaculation and sterility, because the ductus deferens, ejaculatory duct, seminal vesical, and

urethra are under sympathetic control. The second, third, and fourth lumbar ganglia can be removed bilaterally without disturbance of sexual

function.

Be sure to protect the genitofemoral nerve and the iliohypogastric nerves during lumbar sympathectomy.

To maintain urinary continence, a synergistic action should take place between the sphincter of the bladder neck and the proximal urethral

sphincter. The striated distal urethral sphincter (external), which is innervated by the pudendal nerve, prevents urination. Total, or stress

incontinence will be produced by inactivation of these sphincters. In a large number of patients, the etiology of urge incontinence cannot be

determined. They are classified as having idiopathic bladder disorder.

Surgical treatment of intrinsic urethral dysfunction can be accomplished by use of injectable fat27 or collagen or by sling procedures.28

Pharmacologic treatment is based on the distribution of cholinergic receptors and and adrenergic receptors (Fig. 24-16).29

The act of voiding has been difficult to study and early descriptions have blended a few known facts with an excess of imaginative

conjecture. Recent studies have used elegant tracing techniques to examine the precise course of central nerve pathways and neural

projections. These studies have helped to define the neuroanatomy of the central mechanisms that control bladder and urethral function in

animals. Comparative anatomy and non-invasive imaging of human subjects have provided further evidence that would support a unifying

concept for the anatomy of micturition.

Bladder paragangliomas present with hypertensive attacks precipitated by micturition and hematuria. Demirkesen et al.30 presented a case

of bladder paraganglioma at pregnancy causing early preeclampsia.

Fig. 24-16.



Adrenergic and cholinergic receptor distribution in the bladder, urethra, and pelvic floor musculature. (Modified from Bellinger MF.

Myelomeningocele and neuropathic bladder. In: Gillenwater JY, Grayhack JT, Howards SS, Duckett JW. Adult and Pediatric Urology (3rd ed). St.

Louis: Mosby, 1996; with permission.)

Neurogenic (Unstable) Bladder

As Abrams31 stated, "The unstable bladder is well recognized, yet poorly understood." We quote from Freeman and Malvern:32

The unstable bladder (or unstable detrussor) has been defined by the International Continence Society as one that has been

shown objectively to contract (spontaneously or on provocation) during the filling phase while the patient is attempting to

inhibit micturation. Unstable detrusor contractions may be asymptomatic or may be interpreted as a normal desire to void. The

presence of these contractions does not necessarily imply a neurological disorder. Unstable contractions are usually phasic in

type. . . A gradual increase in detrusor pressure without subsequent decrease is best regarded as a change of compliance.

Neurogenic (neuropathic) bladder is found most commonly in children with meningomyelocele. The neural and bony abnormalities vary in

meningomyelocele, and accordingly, the types of neurogenic bladder vary also. Most common is a lax sphincter with poorly contracting

or noncontracting detrusor.

More ominous is the bladder in which there is a hyperactive detrusor and a sphincter that operates out of synch, often closing more

tightly during detrusor contraction. This condition is called detrusor/sphincter dyssynergia. Elevated bladder pressure places the

patient's upper tracts at great risk. Treating children for most neurogenic bladders involves using clean intermittent catheterization

with or without anticholinergics/smooth muscle relaxants.

Although many classification systems for neuropathic bladder exist,29 practically speaking there are two types. An efferent bladder is a

hypertonic bladder with small capacity, presumably due to lack of inhibition from higher levels upon lower spinal cord segments. An

afferent bladder is a hypotonic bladder of large capacity.

Some authors present "atonic" as a third type of neurogenic bladder. However, this is not a neurogenic bladder, but a condition

secondary to long-standing obstruction.

Efferent (Spastic) Neurogenic Bladder

The characteristics of efferent or spastic neurogenic bladder are:

Tone is elevated

Sensation is present

Moderate distention produces pain



Moderate distention produces pain

Intravesical pressure is elevated

The patient reports the following symptoms regarding urination:

Uncontrollable sense of need

Frequency

Urge incontinence

Nocturia

Studies of patients with efferent (spastic) neurogenic bladder show that they may desire to void with the first or second filling (50 ml

to 100 ml) of fluid33 (Fig. 24-17). Moderate distention of the bladder causes severe pain. This type of bladder is commonly associated

with disorders involving the pyramidal tracts. Lesions involving a single pyramidal tract have been alleged as causative factors in the

production of hypertonic bladders. The internal sphincter slowly also becomes hypertonic, but not enough to withstand the effect of

the hypertonic detrusor, which becomes more spastic. Dribbling and, perhaps, incontinence result.

Fig. 24-17.



Spastic neurogenic bladder, caused by a more or less complete transection of the spinal cord above S-2. Function may return with recovery

from spinal shock.

Perhaps the production of spastic neurogenic bladder is responsible for the lack of inhibition from levels above to lower spinal cord

levels. Treatment involves the use of anticholinergics or smooth muscle relaxants that act distal to the neuromuscular junction (e.g.

oxybutynin).

Afferent (Flaccid) Neurogenic Bladder

The filling capacity of afferent or flaccid neurogenic bladder is tremendous. Sensation is present but hyposensitivity produces a delay

in stimulation to empty the bladder. It therefore empties by reflex, as in newborn infants. The pressure of the internal sphincter

remains normal, but there is an inability to relax and the detrusor muscle is hypotonic due to some atrophy.

Patients with afferent (flaccid) neurogenic bladder can tolerate a volume of up to 2 liters of fluid, added in 50 ml quantities33 (Fig. 24-

18). Desire to void, distress, and pain are produced only when greater than usual amounts of fluid have been added. Hyposensitivity,

or complete lack of sensitivity, can be associated with the problem, in which case the desire to void may not occur until after

introduction of 500 ml. Distress and severe pain may be delayed until the bladder volume reaches 800 ml.

Fig. 24-18.



Flaccid neurogenic bladder, caused by a lesion of either the sacral portion of the spinal cord or the cauda equina.

Internal sphincter pressure remains normal, irrespective of the presence of a hypotonic detrusor muscle. The voluntary abdominal

muscles are therefore frequently required to facilitate micturition. This type of bladder is associated with disorders affecting the

afferent pathway (end organs, posterior roots, or posterior spinal columns). Hyposensitivity of the bladder may lead to delayed

awareness of the need to empty the bladder. Atrophy of the detrusor muscle, resulting from prolonged overdistention, plus inability of

the internal sphincter to relax at the proper time may result.33 Treatment for this problem may involve intermittent catheterization,

Foley catheter, or a suprapubic tube. Urinary diversion with simple cystectomy will avoid later complications of a retained

nonfunctioning bladder.34

Treatments for children with neurogenic bladder include artificial urinary sphincter creation35 and augmentation cystoplasty with clean

intermittent self-catheterization.36 However, Bertschy and colleagues37 caution that complications associated with intestinal mucosa

in the bladder occur with some frequency with enterocystoplasty for bladder augmentation.

HISTOLOGY AND PHYSIOLOGY

Transitional epithelium lines the bladder. The color of the mucosa varies. When the bladder is empty, the color is red. When it is full,

the color is pale.

We quote the excellent summary of Lewis38 on the histology and physiology of the bladder epithelium:

The mammalian urinary bladder epithelium (urothelium) performs the important function of storing urine for extended periods,

while maintaining the urine composition similar to that delivered by the kidneys. The urothelium possesses four properties to

perform this function. First, it offers a minimum epithelial surface area-to-urine volume; this reduces the surface area for passive

movement of substance between lumen and blood. Second, the passive permeability of the apical membrane and tight junctions

is very low to electrolytes and non-electrolytes. Third, the urothelium has a hormonally regulated sodium absorptive system;

thus passive movement of sodium from blood to urine is countered by active sodium reabsorption. Last, the permeability

properties of the apical membrane and tight junctions of the urothelium are not altered by most substances found in the urine or

blood. The importance of the barrier function of the urothelium is illustrated by infectious cystitis. The loss of barrier function

results in the movement of urinary constituents into the lamina propria and underlying muscle layers, resulting in suprapubic and

lower back pain and frequent, urgent, and painful voiding.



The nature of the vesical mucosa allows the bladder to expand. The mucosa becomes flattened when the bladder is full of urine. When

the bladder is empty it becomes multilaminar, or wrinkled. However, the area at the trigone is always flat and smooth because it is

fixed to the musculature below. The musculature of the trigone region is apparently continuous with the musculature of the ureters,

and is thus predominantly under control of sympathetic neural innervation. The detrusor muscle is under parasympathetic control.

The mucosa of the urinary bladder is continuous superiorly with the mucosal lining of the ureters and is likewise continuous inferiorly

with the mucosa of the urethra. It is believed that continence and urination are regulated by the musculature organized about the

vesical neck, preprostatic muscular portion of the male urethra, and levator ani musculature. In addition the musculature includes

vectors of urethral supporting tissues and the sphincteric musculature of the urogenital diaphragm. In other words, the pubococcygeus

of the pelvic diaphragm which supports the vesical neck of the urinary bladder may, perhaps, be responsible for the relaxation of the

neck since it moves the neck downward and relaxes the urethrae. Nonetheless, the histology and anatomy of the trigonal region and

the precise mechanisms controlling both urinary continence and voluntary micturition are enigmatic, complex, and not yet fully

understood.

Additional histologic information on the bladder was presented previously in this chapter under the heading "Bladder Wall."

The pathophysiology of the normal bladder is enigmatic and ill understood. The urinary bladder has a dual physiologic destiny:

To act as a reservoir for urine a very simple act. The bladder receives the urine from the ureters.

To contract and expel the urine to the urethra a complex procedure. This involves the innervation of the urinary bladder and the

production of the micturition reflex. The detrusor muscle contracts and the urethral resistance falls.

From the physiologic standpoint, is the parasympathetic nervous system a fellow traveler of the somatic nervous system? Most likely

yes.

SURGERY OF THE URINARY BLADDER

Indications

Many conditions and problems of the urinary bladder require surgery or other treatment. We present a few.

Surgery for Bladder Exstrophy

Kasat and Borwankar39 presented eleven important factors for successful primary closure in staged reconstruction of bladder

exstrophy:

Proper patient selection

Staged approach

Anterior approximation of pubic bones with placement of bladder and urethra in true pelvis

Posterior bilateral iliac osteotomies in all indicated cases

Double-layered closure of the bladder

Two weeks of proper ureteric catheter drainage

Prevention of infection

Prolonged and proper postoperative immobilization

Prompt treatment of bladder prolapse

Prevention of postoperative abdominal distension

Ruling out of bladder outlet obstruction before removal of bladder catheter

Females with exstrophy/epispadias demonstrate anterior displacement of the bladder, urethra, and vagina with lack of development of

anterior pelvic floor musculature. Kropp and Cheng40 recommend total urogenital complex mobilization to normal anatomical position.

Bladder Injuries

Small retroperitoneal perforations of the bladder usually heal with only prolonged Foley catheter drainage. However, larger

retroperitoneal injuries or perforations involving the dome of the bladder, which leak urine into the peritoneal cavity, require open



retroperitoneal injuries or perforations involving the dome of the bladder, which leak urine into the peritoneal cavity, require open

surgical repair and extravesical drainage, in addition to prolonged Foley catheter drainage. Gravity cystogram should be performed prior

to removal of the Foley catheter to exclude persistent urinary extravasation.

The absence of pelvic fluid on a trauma CT scan indicates that bladder rupture is unlikely, but Pao et al.41 caution that a passively

distended opacified bladder may be injured despite an absence of extravasated contrast material.

Bladder Fistulas

Bladder fistulas are of the following types: enteric, colonic, vaginal, uteral, and cutaneous. All may be the result of inflammatory or

neoplastic process, traumatic or iatrogenic.

Iatrogenic and traumatic bladder fistulas may be repaired immediately or delayed by 4 to 6 months to permit resolution of inflammation

and edema. When repair is performed, the involved portion of the bladder and a small circumferential ring of normal tissue should be

excised. The bladder should be closed in non-overlapping layers with absorbable suture. If possible, omentum or other vascularized

tissue should be interposed between the fistula repair and the surrounding structures. Prolonged extravesical drainage and Foley

catheter should be performed.

Lithiasis

Bladder calculi can be treated by performing an open cystotomy and stone removal or by an endoscopic approach. If the latter is used,

the surgeon may use a manual lithotrite to crush the stone into small fragments or an electrohydrolic, laser, or ultrasonic lithotriptor.

Procedures

The three most important surgical procedures for the urinary bladder are cystoscopy, partial cystectomy, and total (radical)

cystectomy. The last two are utilized for malignancy.

Cystoscopy

Endoscopic evaluation of the bladder may be performed using a rigid or flexible cystoscope. Rigid cystoscopy has the advantage of a

wide, clearer image. However, the flexible cystoscope is much more comfortable, especially in men, and permits better visualization of

the dome and around an enlarged prostate. If performed in a gentle fashion, the majority of diagnostic cystoscopies can be done in the

office.

Transurethral removal of noninvasive bladder cancer is performed for histologic study and curative resection of tumors that do not

invade the detrusor muscle. Holzbeierlein and Smith42 caution that there is a high rate of new tumor occurrence.

Partial Cystectomy

Most bladder tumors are resected transurethrally using a resectoscope. Open partial cystectomy is indicated for superficial tumors that

are too large to excise transurethrally or are in a bladder diverticulum. If partial cystectomy is being performed for an invasive tumor, it

should be located in the dome so that a 1 cm margin of normal tissue can be circumferentially resected, and the remainder of the

bladder should be free of other tumor. Typically, partial cystectomy can be performed using a retroperitoneal approach. The bladder

should be entered at a site a few centimeters away from the tumor. The excised surgical specimen should be labeled and sent for

frozen section histologic analysis to exclude positive margins. The bladder is closed in layers with absorbable suture. Prolonged

extravesical drainage and Foley catheter are required.

Bladder augmentation ureterocystoplasty using the lower part of an extremely dilated megaureter was reported by Perovic et al.43

Function of the ipsilateral kidney was preserved.

Total (Radical) Cystectomy

Primary radical cystectomy is considered the standard for care of organ-confined muscle invasive bladder cancer.44 Leissner and

colleagues45 recommend extensive lymphadenectomy as a potentially curative procedure for invasive bladder cancer, and state the

need for a standardized lymph node resection.

In males, the procedure used is cystoprostatectomy in conjunction with urinary diversion. Complete removal of the prostate prevents

residual disease in patients at higher risk for a second malignancy such as an unsuspected prostate cancer.46 In females, the

procedure is anterior exenteration (hysterectomy and bilateral removal of tubes and ovaries) along with urinary diversion.

Whittlestone and Persad47 state that the ileal conduit is considered the "gold standard" following cystectomy. Tainio et al.48 caution

that a gastric segment should never be used as a conduit in the urinary tract.

Laparoscopic Surgery

Denewer et al.49 reported encouraging results using laparoscopic-assisted cystectomy and lymphadenectomy to treat 10 patients with

carcinoma of the urinary bladder. They emphasized, however, that the technique needs further modifications and refinements.



Incisions

A midline incision or a Pfannenstiel incision is excellent for surgery of the urinary bladder (and, as a matter of fact, for any pelvic

surgery). Redman50 beautifully described the various incisions used.

Lower anterior abdominal wall incisions are of 3 types:

Midline lower

Lateral lower

Transverse lower (Pfannenstiel)

The above incisions allow the surgeon several options.

Entry and exploration of the peritoneal cavity

After elevating the peritoneum, exploration of the retroperitoneal space, together with thin or thick vesicoumbilical connective tissue

The surgical anatomy for the incisions is covered in the chapter on the abdominal wall.

Surgical Applications

This is not a book of technique; its emphasis is on surgical anatomy. In radical cystectomy for both males and females, the surgeon

should have good knowledge of the anatomy of the following:

Incision

Pelvic lymphatics

Iliac arteries and veins

Peritoneal reflections

Pelvic ureter

Bladder and its ligamentous supports

Rectum

Deep dorsal vein of penis/clitoris

Urethra

ANATOMIC COMPLICATIONS OF RADICAL CYSTECTOMY

We present in detail the anatomic complications only of radical cystectomy. The excellent chapter of Lieber51 in the book of Smith and

Ehrlich and several other sources form the basis of this presentation.

In the majority of cases, urologic surgery is the surgery of older people. Lieber re-emphasizes the old axiom, "Elderly and poor-risk

patients tolerate one major operation very well, but they tolerate major complications and reoperation very poorly."51

We will discuss the following anatomic complications of radical cystectomy:

Bleeding of arterial or venous origin

Nerve injury

Rectal injury

Impotence



Urinary incontinence

Vaginal cuff complications

Urinary diversion complications

Wound dehiscence

Bleeding of Arterial or Venous Origin

The common iliac artery, the external and internal iliacs, their branches, and their corresponding veins are responsible for bleeding in

radical cystectomy. Clear delineation of the great vessels helps the ligation procedure of the small vessels toward the bladder. The

internal iliacs can be temporarily occluded bilaterally or ligated permanently if the vascular supply to the gluteal region is protected

(Fig. 24-19).

Fig. 24-19.

Ligation of anterior pedicles for cystectomy. (Based on Hinman F Jr. Atlas of Urosurgical Anatomy. Philadelphia: WB Saunders, 1993.)

Bilateral ligation of the internal iliac arteries furnishes eight major pathways of collateral circulation. The very rich collateral circulation

follows:

Uterine artery with ovarian artery from the aorta

Middle rectal artery with superior rectal artery from the inferior mesenteric

Obturator artery with inferior epigastric from the external iliac

Inferior gluteal with circumflex and perforating branches of the deep femoral

Iliolumbar with lumbar branch from the aorta

Lateral sacral with middle sacral from the aorta



Lateral sacral with middle sacral from the aorta

Anastomoses between vessels of the bladder wall and abdominal wall

Anastomoses between the internal and external pudendal arteries

It is advisable to ligate the internal iliac artery distal to the origin of its posterior division, because it is the origin for the superior

gluteal artery. This avoids postoperative gluteal pains secondary to ischemia (buttocks angina).

Remember

In some cases the internal iliac artery has no distinct posterior division and one must search for the superior gluteal artery. It is also

advisable for the surgeon to prepare, isolate, and ligate the arteries and veins that provide the blood supply of the urinary bladder.

The three vesical arteries originate from the anterior division of the internal iliac artery. The vesical veins are easily visible, because they are

located in the same plane as the arteries. Lieber51 advised the surgeon not to drift too far laterally in order to avoid the internal iliac vein.

To avoid further bleeding, the ideal plane should be established between the bladder and the rectum. This plane is between the seminal

vesicles and the rectum, ventral to the anterior lamina of the fascial septum of Denonvilliers. Therefore this blind procedure should be done

slowly and carefully to avoid producing a false pathway between the seminal vesicles and the bladder.

Another source of bleeding can be the deep dorsal vein of the penis and the plexus of Santorini.52 Careful dissection of the vein as it passes

over the bladder neck at the apex and ligation of its three branches are necessary. The venous plexuses can be exposed and ligated close to

the incised endopelvic fascia near the pelvic side wall, and far away from the bladder and prostate.

Nerve Injury

Because the surgeon normally avoids the lateral pelvic wall, the obturator is the only nerve open to injury; even then it is injured only

on very rare occasions. This nerve can be palpated by introducing the index finger into the retropubic space under the pubic ramus

just lateral to the pubic symphysis. The surgeon will feel a cordlike formation containing the nerve and the obturator vessels (Figs. 24-

20, 24-21). The obturator canal can be palpated with ease in many cases, helping one locate the obturator nerve and vessels.

Fig. 24-20.



A finger introduced into the retropubic space identifies the structures entering the obturator foramen. (Modified from Skandalakis LJ, Gadacz

TR, Mansberger AR Jr, Mitchell WE Jr, Colborn GL, Skandalakis JE. Modern Hernia Repair: The Embryological and Anatomical Basis of Surgery.

New York: Parthenon, 1996; with permission.)

Fig. 24-21.

Medial view of the right pelvis. The finger is inserted into the retropubic space under the pubic ramus just lateral to the pubic symphysis. A

cordlike formation containing the obturator nerve, artery, and vein can be felt. The nerve appears as a shiny silver cord. (Modified from

Skandalakis LJ, Gadacz TR, Mansberger AR Jr, Mitchell WE Jr, Colborn GL, Skandalakis JE. Modern Hernia Repair: The Embryological and

Anatomical Basis of Surgery. New York: Parthenon, 1996; with permission.)



Injury to the obturator nerve produces severe disability of the lower extremity by paralyzing the adductor muscles. Because we do not

know the results of neurorrhaphy, use very careful dissection during pelvic lymphadenectomy.

Rectal Injury

To avoid rectal injury, dissect away from the rectal wall. This may not be an option if the patient has had previous radiation because

radiation often results in heavy fixation of the bladder and rectum. Therefore, preparation of the bowel with enemas and antibiotics is

essential. If laceration is recognized in the operating room, closure in two or three layers with non-absorbable interrupted sutures will

suffice. Occasionally, a sigmoid diverting colostomy will be necessary.

Impotence

To prevent impotence following radical cystectomy, the surgeon should preserve the autonomic plexus at the pelvic side walls by

staying close to the seminal vesicles. Walsh et al.53 developed this nerve-sparing technique. They were able to prevent injury to the

nerves innervating the corpora by locating the neurovascular bundle between the lateral pelvic fascia and Denonvilliers' fascia (Figs.

24-22, 24-23, 24-24, and 24-25). For all practical purposes, the neural bundle is located within the envelope of endopelvic fascia

adjacent to the posterolateral aspects of the prostate gland bilaterally.

Fig. 24-22.

Cross section through an adult prostate demonstrating the anatomic relations between the lateral pelvic fascia, Denonvilliers' fascia, and the

neurovascular bundle. (Modified from Walsh PC, Lepor H, Eggleston JC. Radical prostatectomy with preservation of sexual function:

anatomical and pathological considerations. Prostate 1983;4:473-485; with permission.)

Fig. 24-23.



The surgical plane employed in radical prostatectomy (dashed blue line indicates incision). (Modified from Walsh PC, Lepor H, Eggleston JC.

Radical prostatectomy with preservation of sexual function: anatomical and pathological considerations. Prostate 1983;4:473-485; with

permission.)

Fig. 24-24.

The surgical plane employed in radical retropubic prostatectomy, indicating the site for incision (dashed blue line) in the lateral pelvic fascia

which avoids injury to the neurovascular bundle. (Modified from Walsh PC, Lepor H, Eggleston JC. Radical prostatectomy with preservation of

sexual function: anatomical and pathological considerations. Prostate 1983;4:473-485; with permission.)

Fig. 24-25.



The correct site for ligation of the lateral pedicle. (Modified from Walsh PC, Lepor H, Eggleston JC. Radical prostatectomy with preservation of

sexual function: anatomical and pathological considerations. Prostate 1983;4:473-485; with permission.)

The student of radical cystoprostatectomy should study in detail the excellent work of Walsh and colleagues.52-56 The apex of the

prostate should be dissected very carefully, thereby avoiding injury to the neurovascular pedicle. Remember that the cavernous nerves

have a posterolateral pathway in relation to the membranous urethra during their penetration of the urogenital diaphragm, where they

pass laterally to reach the crura of the corpora cavernosa penis.

Urinary Incontinence

In the male, the external sphincter circles the membranous urethra (Fig. 24-26). Avoid incontinence after radical prostatocystectomy

by saving the sphincter when possible. In the female the external sphincter is located at the midurethral segment, where a horseshoe-

shaped formation of striated muscle, the compressor urethra, is present in continuity with the urethral musculature and the sphincter

urethrovaginalis (Fig. 24-27).17 Tanagho8 stated that urodynamically this external female sphincter "shows its significance."

Fig. 24-26.

Histologic section of the membranous urethra of a normal adult male shows the distribution of the smooth intrinsic musculature in the

urethral wall, with circular fiber orientation. It is surrounded by an equally thick intrinsic coat of striated muscle fibers, essentially omega-

shaped, with a defect in the midline posteriorly where it inserts in the perineal body. Note that the external sphincter constitutes an integral

part of the musculature of the urethral wall at the level of the membranous urethra. (From Tanagho EA. Anatomy of the lower urinary tract.

In: Walsh PC, Retik AB, Stamey TA, Vaughan ED Jr. (eds). Campbell's Urology (6th ed). Philadelphia: WB Saunders, 1992; with permission.)

Fig. 24-27.



Sagittal sections of the entire female urethra from the internal to the external meatus. Note the muscular nature of the entire urethral tube

except at its most distal end, which is fibrous and opens to the outside at the level of the vaginal vestibule. The inner longitudinal fibers are

embedded in dense collagen, whereas fibers constitute the bulk of the musculature of the urethral canal from the level of the internal meatus

all the way down to the external meatus, as a direct continuation of the outer longitudinal fibers of the bladder wall. (From Tanagho EA,

Smith DR. Mechanism of urinary continence. J Urol 1968;100:640-646; with permission.)

The complication of urinary incontinence resulting from radical cystectomy depends upon the proper management of the membranous

urethra. Several techniques of neobladder construction exist. The surgeon should use the one with which he or she is familiar. The

surgeon should also try to save as much of the urethra as possible if the urethra is not involved with a tumor.

Vaginal Cuff Complications

When the bladder, urethra, and anterior vaginal wall are removed, a good closure of the defect will avoid leakage of the peritoneal

contents or possible enteric contents secondary to small bowel fistula. The advice of Lieber51 is to close the anterior vaginal wall

distally or longitudinally, or perhaps to separate the posterior vaginal wall from the rectum, bringing it in an anteroposterior direction to

close the defect. Absorbable suture should be used. The vaginal cuff can be closed with interrupted absorbable sutures to prevent the

occurrence of hernias, but not closed watertight, so as to permit drainage of blood and urine. As for enteric fistulas, simple resection



and closure after separation from the bladder is the procedure of choice. Colostomy or bowel resection is done in rare cases.

Urinary Diversion Complications

A loop of small or large bowel can be used for neobladder formation. Therefore, the surgeon should be extremely careful to produce a

good pouch with good blood supply and a perfect ureteroenteric anastomosis. Avoid kinking of ureters and twisting of the bowel which

can produce intestinal obstruction or intestinal leakage.

Wound Dehiscence

Good, intelligent, careful anatomic closure of the abdominal wall is the procedure of choice (see "Incisions" under "Surgery of the

Urinary Bladder").

REFERENCES

1. Hamilton, WJ, Mossman, HW. Hamilton, Boyd and Mossman's Human Embryology (4th ed). Baltimore: Williams & Wilkins, 1972.

2. Kelalis PP, King LR, Belman AB. Clinical Pediatric Urology. Philadelphia: WB Saunders, 1992.

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4. Moore KL, Persaud TVN. The Developing Human (5th ed). Philadelphia: WB Saunders, 1993.

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6. Gastol P, Baka-Jakubiak M, Skobejko-Wlodarska L, Szymkiewicz C. Complete duplication of the bladder, urethra, vagina, and uterus

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7. Basmajian JV, Slonecker CE. Grant's Method of Anatomy (11th ed). Baltimore: Williams & Wilkins, 1989.

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ed). Philadelphia: WB Saunders, 1992.

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technic of the Marshall-Marchetti-Krantz operation. [German] Geburtshilfe Frauenheilkd 42(12):892-894, 1982.

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23. Nakai S, Yos

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Chapter 24 Urinary Bladder