1276 



THE UKO-GENITAL SYSTEM. 



of the bladder, or points where the ureters join the organ. They separate the 

 superior surface from the infero-lateral portions of the inferior aspect of the bladder 

 wall (Fig. 993, A). The posterior border stretches across between the posterior angles 

 of the bladder, and separates the superior from the basal surface of the viscus. The 

 superior surface is related in the male to coils of intestine ; in the female it is 

 related also to the anterior surface of the uterus. The lateral border of the empty 

 bladder lies against the pelvic fascia just above, or at the level of, the arcus tendineus 

 of the levator ani muscle. The ductus deferens crosses the side wall of the pelvis 

 parallel to it, but at a considerably higher level. In median section the cavity of 

 the empty and relaxed bladder often presents the appearance of a Y-shaped chink, 

 the stem of the Y being represented by the urethra as it leaves the organ, and the two 

 limbs by the narrow intervals between the superior surface and the under parts of 

 the bladder wall which lie in front of and behind the urethral orifice. This relaxed 

 form is sometimes described as the diastolic condition of the empty bladder, and is 

 found associated with a bladder wall of but little thickness, and with a concave upper 

 surface. The condition is usually the result of an escape of fluid after death, 

 when the bladder wall has lost the power of contracting. It does not represent 



Lig. umbilicale medium 

 [urachus] 



Tuberculum pubicum 



Obliterated part 



of the umbilical artery 



Inferior epigastric artery 



Ductus deferens 



Colon 



Ureter 



Ilio-pectineal eminence 

 Inferior epigastric 

 artery 



Ductus deferens 



__Urinary bladder 

 (highest point) 



Sacral promontory 

 Ureter 



Common iliac artery 



FIG. 994. VIEW LOOKING INTO THE PELVIS FROM ABOVE AND SOMEWHAT BEHIND. 

 The bladder has been artificially distended. 



a normal condition of the organ in the living. The normal empty bladder 

 is strongly contracted, and its wall is thick and firm. A distinctly Y-shaped 

 appearance is not presented by its cavity in median section, but the interior of the 

 organ is seen as a simple narrow interval continuous with the canal of the urethra. 

 Distended Bladder. As the bladder fills with fluid the superior wall i 

 raised upwards from the infero-lateral and basal walls, and, at the same time, the 

 borders separating the superior from the other surfaces of the bladder become at 

 first more rounded and then nearly obliterated. The lateral borders of the bladder 

 becoming in this manner opened out, give rise to so-called lateral surfaces i 

 the distended organ. These surfaces, however, are not sharply marked off, 

 and are directly continuous with the superior surface. During distension, 

 also, the angles present in the empty condition of the organ become rounde< 

 as the entire bladder wall becomes more uniformly convex. The general 

 shape of the bladder becomes altered during distension; the tetrahedral form 

 of the empty organ is lost, and the bladder as it becomes filled assumes first 

 somewhat spherical, then an oval contour. During distension the enlargii 

 bladder comes to occupy more and more of the pelvic cavity, displacing upwards 

 the portions of the colon and small intestine which may lie in the pelvis when tl 

 organ is empty. Until all the available pelvic space has been filled up, the form 



