380 



BLADDER, NORMAL ANATOMY. 



part of it as appertaining to the posterior region. 

 Anatomically we consider this incorrect, as the 

 vesicular seminales are acknowledged by all to 

 be situated on the inferior region, and the cul- 

 de-sac of the peritoneum certainly descends 

 between these bodies to within nearly one-half 

 or three-fourths of an inch from the prostate 

 gland. In a practical point of view it is most 

 essential to keep this in mind, because in the 

 operation ofrecto-vesicalparacentesis this mem- 

 brane is endangered, and would certainly be 

 perforated if the trochar were passed through 

 the posterior portion of this region. The sur- 

 face of the bladder winch can be opened from the 

 rectum in that operation is comparatively small; 

 it is of a triangular form, nearly equilateral, 

 situated on the anterior part of this region. The 

 base is behind marked by the convex border of 

 the peritoneal cul-de-sac : the apex is at the 

 notch in the base of the prostate gland, and the 

 sides are the vasa deferentia and vesiculre 

 seminales. While all these parts are in situ, 

 this space is but small ; when, however, the 

 bladder has been removed from the subject, 

 distended, and dissected, this space appears 

 much more ample, because the peritoneum 

 recedes from it in proportion as the attach- 

 ments of the former have been loosened. 



The bladder presents to our notice three 

 diameters, viz. the transverse, antero-posterior, 

 and the vertical ; the latter is also called its 

 axis. In the contracted state the antero-pos- 

 terior can scarcely be considered as existing ; 

 but when distended, this and the transverse 

 diameters are nearly equal. In all states, at 

 least in the male, the vertical diameter or axis 

 is the longest ; this line leads in the adult from 

 the centre of the upper region to that of the 

 lower region or fundus : in the foetus and infant 

 it leads from the urachus to the orifice of the 

 urethra; if this line be contrasted with the 

 axis of the trunk or abdomen, and with that 

 of the pelvis, it will be found to correspond 

 very nearly with the direction of the latter, and 

 to pass very obliquely with respect to the 

 former. The axis of the trunk may be regarded 

 as nearly a vertical line, descending through the 

 thorax and abdomen to the pubis, whereas the 

 axis of the pelvis, or rather of its superior 

 orifice, will pass obliquely downwards and 

 backwards, and if produced at either end, it 

 will pierce the recti muscles between the um- 

 bilicus and pubis anteriorly, and the lower end 

 of the sacrum posteriorly. The vertical axis 

 of the bladder in the adult is on a lower plane, 

 but nearly parallel to that line ; in the foetus it 

 is more parallel to that of the trunk, the blad- 

 der at that age being placed more in the ab- 

 domen, and in a more vertical direction than 

 in the adult. 



The bladder is composed of several mem- 

 branous laminae, called coats or tunics : these 

 are essentially three in number, a serous, a 

 muscular, and a mucous. They are connected 

 together by cellular tissue, the laminae of which 

 being two in number are also considered coats ; 

 so that the whole number of tunics is stated 

 by most writers as five. First, the serous or 

 peritoneal is but a partial coat ; it covers those 



portions only which come in contact with some 

 of the abdominal or pelvic viscera, namely, all 

 the posterior region, and the posterior portions 

 of the lateral, and of the superior and inferior 

 regions ; consequently it is deficient on all 

 the anterior region, and on the anterior part of 

 the superior, and of the lateral and inferior 

 regions. The course of the vasa deferentia 

 marks the extent or the limits of this mem- 

 brane on the bladder; all that portion which is 

 behind and between these tubes is covered by 

 it, except the small triangular area already 

 noticed on the inferior region; all that which is 

 anterior to these vessels is uncovered by this 

 membrane. The peritoneum arrives at this 

 viscus from the fore-part of the rectum in the 

 male, and from that of the uterus in the female, 

 and is continued from its lateral regions to the 

 iliac fossa?, and from its superior fundus to the 

 inside of the recti muscles. This membrane is 

 not very closely attached to the subjacent 

 coat ; it can be easily separated from it ; it is 

 much stronger and more elastic on this organ 

 than on any of the chylopoietic viscera. When 

 the bladder is distended, there is more in pro- 

 portion covered by peritoneum than when it is 

 contracted. The female bladder has more of the 

 peritoneum on its upper fundus, and less on its 

 lower fundus than the male bladder, and in the 

 foetus and infant it is still more extensively 

 covered by this membrane, which then extends 

 over the whole of the upper region and over a 

 small portion of the anterior. As the peritoneum 

 passes from the sides of the bladder to the 

 iliac fossa, it forms folds, improperly called the 

 lateral ligaments, and in passing from the back 

 of the bladder to the rectum or uterus, a similar 

 fold on each side, called the posterior ligaments 

 of the bladder. Between these the cul-de-sac 

 of the peritoneum descends ; this in the male 

 subject is the lowest portion of the peritoneal 

 cavity, it extends to within about three inches 

 and a half of the anus : in ascites it has been 

 known to be somewhat lower, and has even 

 been tapped in this situation from the rectum. 



2dly. The external or first cellular coat con- 

 nects the serous to the muscular tissue ; it also 

 covers those regions of the bladder where the 

 serous membrane is deficient. In the lateral 

 regions it is more distinct and thick, and is 

 particularly abundant anteriorly between it and 

 the pubes, where it is also very lax, to allow 

 this organ when distended to move freely as it 

 rises out of the pelvis into the abdomen. It 

 contains some but not much adipose matter ; 

 towards the inferior and lateral parts it con- 

 tains many bloodvessels, chiefly venous, and a 

 great number of nerves, which can be distinctly 

 traced from thence in all directions over the 

 bladder. Towards the vesicular it is dense and 

 white, and supports a number of veins; this 

 coat is strong, resisting, and elastic; it binds 

 together, supports, and assists the muscular 

 fibres. 



The third coat of the bladder is the muscular : 

 this is composed of fasciculi running in dif- 

 ferent directions, and which, though they appear 

 pale and feeble when contrasted with the volun- 

 tary muscles, are yet much stronger and redder 



