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branous part of the urethra ; d, section of the left corpus cavernosum ; c, bulb of the spongy body of
the urethra ; /, Cowper's gland ; g, section of the body of the pubis ; h, sphincter ani muscle ; i, part
of the left vas deferens ; m, articular surface of the sacrum ; n, divided spine of the ischium ;
o, coccyx ; p, prostate gland ; r, r, peritoneum ; r', recto- vesical pouch ; u, left ureter ; v, left
vesicula seminalis.

upper aspect covered by peritoneum, an anterior, lying above the pubo-prostatic
ligaments, and behind the pubic symphysis, and a posterior, which is in relation



THE BLADDER.



207



with the rectum, vasa defereutia, and vesiculae seminales in the male, and the
cervix of the uterus and upper part of the vagina in the female. Both_the anterior
and posterior surfaces are uncovered by peritoneum.

On the other hand, when the bladder is empty and contracted (in systole) the
two limbs of its cavity are much shortened, its mucous membrane is thrown into




Fig. 228. VERTICAL MEDIAN SECTION OF THE PELVIS OF AN ADULT MALE SUBJECT. (Braune.) \

1st s, body of 1st sacral vertebra; P. s., pubic symphysis ; Bl., bladder; R, R, R, rectum;
P, P, prostate ; P', middle lobe of prostate ; F, retro-pubic pad of fat ; Bu., bulb ; p. c., peritoneal
cavity ; j. i., convolutions of jejuno-ileum.

numerous folds, its muscular coat is greatly thickened, and its superior aspect is
rounded and convex. As the relaxed bladder is gradually filled with urine it
expands chiefly in an upward direction, its superior surface being separated from
the anterior and posterior surfaces, and becoming convex towards the peritoneal
cavity. When moderately filled it is still contained within the pelvic cavity, and
has a rounded form (fig. 227, a), but when completely distended it rises above the
brim of the pelvis, and becomes egg-shaped ; its larger end, which is called the



208



THE URINARY ORGANS.



base, orftindus, being directed downwards and backwards towards the rectum in the
male and the vagina in the female ; and its smaller end, or summit, resting against
the lower part of the anterior wall of the abdomen. Immediately in front of
the base is the portion which joins the urethra, and is often named the ctrvix,
or neclc. When the bladder is excessively distended (fig. 22',)) it may rise into
the abdomen nearly as high as the umbilicus, and it also sinks somewhat in
the pelvis, pushing the prostate and lower end of rectum downwards and back-
wards. The long axis of the distended bladder varies in different cases, being
modified by the degree of distension of the bladder itself, as well as that of

Fig. 229. MEDIAN SECTION OF THE PELVIS

OF AN ADULT MALE SUBJECT. (Rudinger.)

L. body of 5th lumbar vertebra ; s, body of
1st sacral vertebra ; p, s, pubic symphysis ; p,
prostate ; B, bulb of corpus spoiigiosum ; u,
urethra ; B, umbilicus ; A, peritoneum. The
reflection of the peritoneum from the anterior
abdominal wall on to the bladder is higher than
normal.

the rectum and other portions of
the intestine that may be in relation
with it. In a section of Braune's (see
fig. 228), in which the bladder was
moderately distended, it is almost hori-
zontal, while in one by Rudinger (see
fig. 229), in which the bladder was
greatly distended, it is rather more
nearly vertical than horizontal. While
in the male the longest diameter of
the moderately distended bladder is
directed from its base to its summit,
in the female the transverse diameter is
the longest.

Connections and Relations.
While freely movable in all other direc-
tions, the bladder is fixed to the walls
of the pelvis in the neighbourhood of

the urethral orifice, its mucous and muscular coats being here continuous with those
of the prostatic portion of the urethra, while its fibrous investment is connected with
the pelvic wall by bands of fibrous tissue, called the true ligaments of the bladder
(see Yol. II., Pt. 2). It is supported, moreover, by strong areolar connections with
the rectum and prostate or uterus and vagina, according to the sex, in a slighter
degree by the two ureters, the obliterated hypogastric arteries, and the urachus, by
numerous blood-vessels, and, lastly, by a partial covering of the peritoneum, which,
in being reflected from this organ in different directions, forms duplicatures, named
\hQ false ligaments of the bladder.

The antero-inferior or pubic surface is entirely destitute of peritoneum, and is
in apposition with the redo-vesical fascia, the symphysis and body of the pubis, and,
if the organ be full, the lower part of the anterior wall of the abdomen. It is con-
nected to these parts by loose areolar tissue. The lower part of this surface, close
to where it joins the prostate, is attached to the back of the pubis by two strong
bands of the recto-vesical fascia, named the anterior true ligaments. This surface of
the distended bladder may be punctured just above the pubis without wounding the
peritoneum.




THE BLADDER.



209



The superior or abdominal surface is entirely free, and covered everywhere by
the peritoneum, which in the male is prolonged also for a short^ distance upon the
base of the bladder. In the male this surface is often in contact with the sigmoid
loop of the colon, and in the female with the uterus, as well as, in both sexes, with
convolutions of the small intestine. Beneath the peritoneum, in the male, a part of
the vas deferens is found on each side of the hinder portion of this surface.

The summit is connected to the anterior abdominal wall by a tapering median
cord, named the urachus, which is composed of fibrous tissue, mixed at its base with
plain muscular fibres, which are prolonged upon it from the bladder. This cord,
becoming narrower as it ascends, passes upwards from the apex of the bladder



Vl.v: Ret.




Sph.ani. cxJL



Zf.



Fig. 230. MEDIAN SECTION OP THE PELVIS OF A NKWLY-BORN MALE CHILD. (Disse.)

V.l. v, body of 5th lumbar vertebra; V.s.v, body of 5th sacral vertebra ; 8y, pubic symphysis ;
Ret, rectum (distended) ; Prt, peritoneum ; Bspr, prasvesical cleft ; Pro, placed just below median
lobe of prostate ; Lf, longitudinal muscular fibres of rectum ; 1, sphincter ani int.

between the linea alba and the peritoneum, to reach the umbilicus, where it
becomes blended with the dense fibrous tissue found in that situation.

The urachus, which forms in the early foetal state a tubular connection between the
urinary bladder and the allantois, preserves, according to Luschka, vestiges of its original
condition in the form of a long interrupted cavity, with irregularities and dilatations,
lined with epithelium similar to that of the bladder, and sometimes communicating by a fine
opening with the vesical cavity.

As during distension the summit of the bladder rises more rapidly than the
peritoneum is detached from the anterior abdominal wall, a peritoneal pouch,
gradually increasing in depth, is formed between the top of the bladder and the
anterior abdominal wall. It is generally estimated that, even in extreme distension,
the bladder is seldom uncovered by peritoneum for more than two inches above the
pubic symphysis.

The sides of the bladder, when this organ is empty, are very narrow, but when
it is distended they are rounded and prominent, and are each of them crossed
obliquely by the cord of the obliterated hypogastric artery, which is connected
posteriorly with the superior vesical artery, and runs forwards and upwards to the
umbilicus, approaching the urachus above the summit of the bladder. Behind and

VOL. III., PT. 4. P



210



THE URINARY ORGANS.



above this cord the side of the bladder is covered with peritoneum, but below and in
front of it the peritoneum does not reach the bladder, which is here connected to
the sides of the pelvic cavity by loose areolar tissue containing fat, and, near
its anterior and lower part, by the broad expansion from the recto-vesical fascia,
forming the lateral true ligament. The vas deferens crosses obliquely the hinder
part of this lateral surface, from before backwards and downwards, and turning
over the obliterated hypogastric artery, descends on the inner side of the ureter,
to the bass of the bladder (fig. 232).




Fig. 231. MEDIAN SECTION OF THE PELVIS OF A MALE CHILD 7 MONTHS OLD. BLADDER NATURALLY
DISTENDED WITH URINE. Natural size. (J. S.)

p, peritoneum ; s. p. , pubic symphysis ; B, bladder ; R, rectum ; It, bulb of corpus spongiosum. In
this specimen the distance from the umbilicus to the top of the pubic symphysis was 7 cm., and the
vertical extent of the bladder in contact with the anterior abdominal wall and uncovered by peritoneum
was 3 cm.

The anterior and lateral surfaces of the bladder, between the anterior and lateral
true ligaments of the bladder below and the peritoneum above, are connected with
the neighbouring structures by loose areolar tissue, an arrangement which obviously
must facilitate the movements of the bladder. The space occupied by this tissue is
sometimes termed the cavum prcevesicak, or cavum Retzii.

The base or fundus (fig. 232) is the widest part of the bladder. It is directed
downwards as well as backwards, and differs according to the sex in its relations to
other parts. In the male it rests against the second portion of the rectum, and is
covered superiorly for a short space by the peritoneum, which, however, is imme-
diately reflected from it upon the rectum, so as to form the recto-vesical pouch
(fig. 227). Below the line of reflection of the serous membrane the base of the



THE BLADDER.



211



bladder is adherent to the rectum by dense areolar tissue over a triangular area
bounded at the sides by the vasa deferentia and vesiculas seminates ffig^232), while
in front its apex reaches the prostate gland. It is in this triangular space, which,
in the natural state of the parts, is by no means so large as it appears after they
a.re disturbed in dissection, and seldom measures more than an inch from base to
apex, that the bladder may be punctured from the rectum without injury to the
peritoneum. In the female the base of the bladder is of less extent, and does not

Fig. 232. BASE OF THE MALE BLADDER,

PROSTATE, &C., IN THE MALE. (J. S.)

B!, part of base covered by peri-
toneum, separated by a dotted line from
a triangular space left uncovered by that
membrane; u, ureter; s. v., seminal
vesicle ; E. D., ejaculatory duct ; p, pros-
tate ; M. , membranous part of urethra ;
B, bulb ; c. s., corpus spongiosum ; c. a,
Cowper's gland.

reach so far back in the pelvis as
in the male, for it rests against
the front of the neck of the uterus
and the upper part of the ante-
rior wall of the vagina, both of
which organs intervene between
it and the rectum. This part of
the bladder is connected with the
vagina and cervix uteri by loose
areolar tissue, and above it there
is a shallow utero-vesical pouch
of peritoneum. In both sexes
the vesical orifice of the urethra
is usually the lowest part of the
bladder in the erect posture. It
is generally situated about an
inch behind the middle of the
pubic symphysis.

Disse (Merkel u. Bonnet, Anato-
mische Hefte, i) found that the
distance of the orifice from the con-
jugate of the pelvic inlet in seven
adult males varied from 44 mm. to
65 mm., while in women it was
placed more deeply in the pelvis,
being, on an average, 60 mm. below
the pelvic inlet.

Ligaments of the bladder. The true ligaments of the bladder, four in number,
two anterior and two lateral, all derived from the recto-vesical portion of the pelvic
fascia, are described in Vol. II., Pt. 2.

The false ligaments, or peritoneal folds, are described as five in number. Two
of them, named posterior false ligaments or recto-vesical folds, run forwards in
the male along the sides of the rectum to the posterior and lateral aspects of the
bladder, and bound the sides of the recto-vesical cul-de-sac. In the female these
posterior folds pass forwards from the sides of the uterus, and are comparatively
small. The two lateral false ligaments extend from the iliac fossse to the sides of
the bladder, which they join at the level of the obliterated hypogastric arteries.
The superior false ligament (ligamentum suspensorium) is the portion of peritoneum

p 2




212 THE URINARY ORGANS.



which descends from the umbilicus on the urachus and obliterated hypogastric
arteries to the summit of the bladder.

Peculiarities in Shape and Position according to Age. In the newly-
born child the bladder is much higher than in the adult. Thus, its urethral
orifice is at the level of the upper border of the pubic symphysis, and the anterior
surface of the bladder, entirely uncovered by peritoneum, lies against the anterior
abdominal wall, opposite about the lower two-thirds of the space between the pubes and
the umbilicus (fig. 230). If the bladder be empty, its cavity in a median section shows
a long anterior limb passing from the urethral orifice upwards and forwards towards the
umbilicus, but there is no indication of a posterior limb such as has already been
described in the adult. If the bladder be distended, it usually has an ovoid form, with
the large end of the oval directed downwards and backwards. The bladder is
commonly described as being at this age an abdominal organ, but, as a rule, only
one-half of it lies above the plane of the pelvic inlet. After birth the bladder
rapidly descends into the pelvis, and acquires a more rounded form when con-
tracted. In an infant three and a half months old, with the bladder contracted,
the peritoneum was reflected from the anterior abdominal wall on to the bladder
10 mm. above the pubic symphysis, the distance from this point to the umbilicus
being 48 mm. Again, in a boy, aged five years, in which the bladder was also
contracted, the peritoneum passed on to the back of the pubic symphysis before
being reflected on to the bladder (Symington). According to Disse, the vesical
orifice of the urethra sinks rapidly from birth up to the beginning of the third year,
then slowly until the commencement of the ninth year, when it remains stationary
until puberty, at which period it again slowly descends until it gains its adult
position.

Interior of the bladder. On opening the bladder, its internal surface is
found to be lined by a smooth membrane, which is comparatively loosely attached
to the other coats, so that in the empty condition of the organ it is nearly every-
where thrown into small wrinkles or rugae, which disappear as soon as the bladder is
distended. Besides these, the interior of the bladder is often marked by reticular
elevations or ridges, corresponding with fasciculi of the muscular coat.

At the lower part of the bladder is seen the orifice leading into the urethra,
around which the mucous membrane is corrugated longitudinally. Immediately
behind the urethral opening, at the lower part of the fundus, is a smooth triangular
surface, having its apex turned forwards, which, owing to the firmer adhesion of the
mucous membrane to the subjacent tissue, never presents any rugee, even when the
bladder is empty. This surface is named the trigone (trigonum vcsicce, Lieutaud) ;
at its postero-superior angles are the orifices of the two ureters, situated in a
distended bladder about an inch and a half from each other, and nearly the same
distance from the antero-inferior angle, where the bladder opens into the urethra.
When the bladder is contracted, this area is diminished in size.

The orifices of the ureters, presenting the appearance of oval slits, are directed
obliquely forwards and inwards : they are united by a curved elevation, convex
in front, which extends generally outwards and backwards beyond them, and which
corresponds in position with a muscular band which joins them together and to the
neck of the bladder. Proceeding forwards from opposite the middle of this is
another slight elevation of the mucous surface, named the uvula resicce, which
extends to the posterior margin of the urethral orifice. In the female the trigone is
small and the uvula indistinct. In the male the uvula lies a little in advance of
the middle lobe of the prostate, and is sometimes prolonged on the posterior wall of
the prostatic portion of the urethra as far as the verumontanum. It is produced by
a thickening of the submucous tissue. In its natural state this may contribute to
the more perfect closure of the orifice of the bladder.



THE BLADDER. 213



STBUCTUBE OF THE BLADDER.

The bladder is composed of a serous, a muscular, a submucous, and a mucous
coat, and supplied with numerous blood-vessels and nerves.

The serous or peritoneal coat is a partial covering, investing only the posterior
and upper half of the bladder, and reflected from it upon the surrounding parts in
the manner already described in detail.

The muscular coat consists of unstriped muscular fibres, which are described
as forming layers, the outer of which consists of bundles of fibres more or less
longitudinal, and the next of fibres more circular in disposition ; while beneath this
is another imperfect longitudinal layer.

The external longitudinal fibres (fig. 233, A, B, c) are most distinctly marked on
the anterior and posterior surfaces of the bladder. Commencing in front at the
neck of the organ, from the pubes in both sexes (musculi pubo-vesicaks}, and, in
the male, from the adjoining part of the prostate gland, they may be traced
upwards along the anterior surface to the summit of the bladder ; and they may
likewise be followed down over the posterior surface and base to the under part
of the neck of the bladder, where they become attached to the prostate in the
male, and to the front of the vagina in the female. Upon the sides the superficial
fasciculi run more or less obliquely, and often intersect one another ; in the male
they reach the prostate. At the summit a few are continued along the urachus.
The longitudinal fibres taken together constitute what has been named the detrusor
urince, muscle, but, according to Griffiths, these fibres "do not form a separate
muscle, and have not a separate function."

The so-called circular fibres form a thin and somewhat irregular reticulated
layer distributed over the body of the bladder, having various appearances in
different bladders. Their course may -in general be looked upon as transverse, but
for the most part throughout the upper two-thirds of the bladder they cross one
another in very oblique bands : towards the lower part of the organ they assume a
more circular course, and upon the fundus and trigone form a tolerably regular
layer. Close to and around the urethral orifice, in immediate connection with the
prostate in the male, they are often described as forming a thick band of circular
fibres, which has been named the sphincter vesicce. According to Griffiths, there is,
however, no thickening of the muscular fibres in this situation to justify the term of
sphincter.

The third stratum of fibres, still more deeply situated, and which might be
termed internal longitudinal, was first described by Ellis, who distinguished it as
" submucous." It is thin, and its bundles have a reticular arrangement, but with a
general longitudinal direction. At the trigone the inner bands of muscular fibres
are united together and to the mucous membrane by dense areolar tissue, while
they are separated from the external longitudinal fibres by a thin layer of loose areolar
tissue.

The muscular coat of the bladder forms so irregular a covering that, when the organ is
much distended, intervals arise in which the walls are very thin ; and, should the internal or
mucous lining protrude in any spot through the muscular bundles, a sort of hernia is pro-
duced, which may go on increasing, so as to form what is called a vesical sacculus, 01
appendix vexicre, the bladder thus affected being termed saccultitcd. Hypertrophy of the
muscular fasciculi, which is liable to occur in stricture of the urethra or other affections
impeding the issue of the urine, gives rise to that condition named the fasciculated bladder,
in which the interior of the organ is marked by strong reticulated ridges or columns, with
intervening depressions.

Next to the muscular coat, between it and the mucous membrane, but much
more intimately connected with the latter, is a well-marked layer of areolar tissue,



214



THE URINARY ORGANS.



A.






Fig. 233. DISSECTIONS SHOWING THE COURSE OF THE SKJSCULAR FIBRES OF THE BLADDER (Allen
Thomson, after Pettigrew, and from nature). ^-.

A. From the front.

On the right side the superficial fibres are shown ; on the left the deep or circular fibres chiefly are
displayed, a, on the right side, the median and most superficial bands of the longitudinal fibres, in
'which a slight clecussation of fibres is seen ; a', those diverging somewhat ; a", the lowest, which pass
much more obliquely ; the attachment of the longitudinal fibres to the prostate is shown ; on the left
side, c, the upper, c', the middle, c", the lowest set of circular or deeper fibres ; at s, the thickest and
most transverse sets of these fibres forming the sphincter ; p, right half of the prostate, the left
half having been removed ; u, the urachus, into which some of the longitudinal 'fibres are seen
prolonged.

B. From the back.

On the right side the superficial fibres are displayed ; on the left the deeper fibres of the same
kind or intermediate fibres, and some of the circular fibres ; b, b, the median, most superficial and
strongest bands of longitudinal fibres on the right side ; V, the more diverging set of fibres near the
middle of the bladder ; b", the most divergent fibres which surround the entrance of the ureters ; on
the left side, c, c', and c", indicate the deeper circular fibres passing round at various levels, and
crossing with the deeper diverging fibres posteriorly ; , the most transverse fibres at the neck forming
the sphincter ; u, the urachus ; ur, the ureters ; the left half of the prostate has been removed to
show the sphincter ; v, part of the right vas deferens and vesicula seminalis.

C. From the left side.

The anterior and posterior superficial fibres are seen running from below upwards, crossing each
other by their divergence on the side of the bladder, and are indicated by the same letters as in the
preceding figures ; at c, a portion of the anterior longitudinal fibres has been removed so as to expose
th-3 deeper circular fibres.



THE BLADDER. 215

the vascular or submucous coat. This submucous areolar layer contains a large
number of fine coiled fibres of elastic tissue.

The mucous membrane of the bladder is soft, smooth, and of a pule rose colour,
It is continuous above with the lining membrane of the ureters and kidneys, and
below with that of the urethra. Neither here nor in the ureters is the mucous
membrane provided with a muscularis mucosae. It adheres loosely to the muscular
tissue, and is thus liable to be thrown into wrinkles, except at the trigone, where
it is always more even. It is covered with a (transitional) stratified epithelium
(fig. 234), similar to that of the ureters. The cells vary much in form according
to the condition of distension of the bladder, for in the distended organ they are
flattened out so as to cover a larger surface, while in the empty condition of the
bladder they are of less diameter and proportionately higher. Many of the super-
ficial cells contain two nuclei. The deeper cells divide by karyokinesis, and the newly
formed cells take the place of others which are thrust towards the surface. There are
no definite glands in the bladder, but in some places there are solid down-growths




Fig. 234. EPITHELIUM OF THE URINARY BLADDER.
a, superficial ; b, intermediate ; and c, deep layer of cells, partly double.

of the deeper epithelium cells into the mucous membrane, which have sometimes
been described as true glands.

Vessels and nerves. Arteries. The superior vesical arteries proceed from
the remaining pervious portions of the hypogastric arteries ; in the adult they appear
as direct branches of the internal iliac. The inferior vesical arteries are usually
derived from the anterior division of the internal iliac. In the female the uterine
arteries also send branches to the bladder. The neck and base of the organ appear
to be the most vascular portions. The veins form large plexuses around the neck,
sides, and base of the bladder ; they eventually pass into the internal iliac veins.
The lymphatics follow a similar course. Nerves. The nervous supply of the
bladder is bilateral, each half having its own nerves. On each side the nerves are



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