igo2 



HUMAN ANATOMY. 



includes the uncertain part of the bladder between the apex and the fundus. The 

 term ?ieck is sometimes applied to the region immediately surrounding the urethral 

 orifice, although a distinct neck in the usual sense does not exist. The intersections 



of the lateral and posterior bor- 

 FiG. 1617. ders mark approximately the 



points at which the ureters enter 

 the vesical wall. As pointed out 

 by Dixon/ the attachments of 

 the ureters correspond to the lat- 

 eral angles of the trigonal figure 

 that the empty bladder resembles 

 when viewed from above, the 

 apex being the anterior angle. 



Apex, from which passes the 



urachus 



Vas 

 deferens 



Ureter 



Ampulla 



Seminal vesicle 



Urinary bladder, slightly distended and hardened in situ, 

 from formalin subject ; viewed from above. 



The cavity of the strongly con- 

 tracted bladder,, as seen in sagittal 

 sections of organs hardened hi situ, 

 is little more than a cleft bounded 

 above and below by the thick vesi- 

 cal walls and below continuous with 

 the urethra ; in the vicinity of the 

 ureteral orifices, however, the lumen 

 broadens into the lateral recesses 

 which are never entirely effaced 



Left ureter 



Right 

 ureter 



Seminal 

 vesicle 



Prostate 

 gland, pos- 

 terior sur- 

 face 



asa deferentia 



Superior surface 



Apex 

 1 ■?J) 



( Luschka) . The modifications of the 

 lumen sometimes seen, more frequently in women and especially in organs not hardened in situ, 

 in which the superior surface is more or less sunken and in consequence the vesical cavity is 

 crescentic or V-shaped in mesial section, are to be regarded as the result of post-mortem change 

 and not as representing conditions existing during life, since normal contractions of the muscular 

 vesical sac are little calculated to produce such forms. The empty bladder measures in length 

 from 5-6 cm. (2-2^^ in.), in breadth from 4-5 cm. (i>^-2 in.'), and in thickness from 2-2.5 crn- 

 {^i-i in.) (Waldeyer). 



In the distended bladder the demarcation between the surfaces above described is gradually 

 effaced until, in extreme expansion, the organ assumes a general ovoid form in which the supe- 

 rior and inferior surfaces and the fundus are uninterruptedly continuous and all indication of 

 the borders is completely obliterated. Such extreme changes, however, accompany only exces- 

 sive and unusual distention, the alterations taking place under normal conditions, with a prob- 

 able maximum capacity of from 250-300 



cc. (7>^-9 fl. oz. ), being much less radical. Fig. 1618. 



When the bladder begins to fill, the region 

 first to be affected is the posterior and lower 

 lateral portions of the organ, expansion oc- 

 curring more rapidly in the transverse than 

 in the longitudinal axis (Delbet), which for 

 a time retains a generally horizontal direc- 

 tion. With increasing distention the blad- 

 der invades the paravesical fossae at its sides, 

 behind is pressed against the seminal vesi- 

 cles, which in the empty condition of the 

 bladder extend laterally as transverse wings 

 and touch the vesical wall only with their 

 inner ends, and encroaches upon the recto- 

 vesical pouch and the rectum. The con- 

 dition of the latter also influences the direc- 

 tion of the vesical expansion, since the filled 

 rectum decreases the available space behind 

 and forces the bladder upward and forward. 

 Not until the distention has progressed to a 

 considerable degree does the antero-inferior 



segment lengthen and undergo upward displacement and the apex rise much above the pubic 

 symphysis ; and only after the distention greatly exceeds physiological limits and becomes very 

 excessive does the bladder altogether lo.se its pyriform contour and become symmetrically ovoid. 

 The highest point of the greatly enlarged organ no longer corresponds with the attachment of 



^ Anatom. Anzeiger, Bd. xv., 1899. 



-'. Cut edge of 



I peritoneum 



Latero-inferior 

 surface 



Prostate gland, lateral surface 



Preceding- preparation viewed from side, showing relations 

 of bladder, associated ducts, and prostate. 



