PRACTICAL CONSIDERATIONS: THE BLADDER. 1911 



tinence. In other less fortunate cases in which the ureteral openings were on the 

 surface of the body, implantation of the ureters into the intestinal tract (page 1901) 

 has been done with varying degrees of success. 



Extroversio7i (exstrophy) of the bladder, the most frequent congenital ab- 

 normality of this organ, is associated with failure of the ventral plates forming, the 

 abdominal wall to unite in the mid-line. In this condition, which occurs in males in 

 from 80 to 90 per cent, of cases, the symphysis pubis and the anterior wall of the 

 bladder frequently are also lacking, and the posterior vesical wall — protruded by 

 intra-abdominal pressure — forms a rQunded prominence, deep red in color, from 

 chronic congestion. The ureteral orifices are often plainly visible. Cryptorchism, 

 bifid scrotum, inguinal hernia, and epispadias are frequently present. Although the 

 opinions regarding the causes and factors leading to these malformations are various 

 and conflicting, it is certain that these defects depend upon faulty development at a 

 very early period of foetal life, probably in connection with abnormalities of the 

 allantois and of the cloacal region of the embryo, and that the suggested explana- 

 tions on a mechanical basis, as over-distention of the allantois or unusual shortness or 

 location of the umbilical cord, are entirely inadequate to account for malformations 

 which often so profoundly affect the entire lower segment of the anterior body-wall 

 and the associated organs. 



Occasionally a vesica- abdominal fissure occurs without extroversion, when the 

 posterior wall of the bladder will be concave instead of convex and partially covered 

 by the imperfect abdominal wall. 



The posterior wall of the bladder and the anterior wall of the rectum or vagina 

 may be defective at birth, resulting in a congenital vesico-rectal or vesico-vaginal 

 fistula. 



The foetal communication between the extra- and intra-abdominal portions of 

 the allantoic sac may remain pervious, so that the urachus, instead of becoming a 

 fibrous cord extending from the umbilicus to the summit of the bladder, is patent 

 and constitutes a channel by means of which urine is discharged at the navel. 



Cystocele. — A portion of the bladder may be found either alone or together 

 with intestine or omentutii in the sac of an inguinal or femoral hernia, or more 

 rarely it may be part of an obturator or perineal or ventral hernia. 



The ordinary causes of abdominal hernia (page 1759) favor the production of 

 this condition. In their presence, and especially if there is also present an intestinal 

 hernia of long standing, a thinned and dilated bladder may readily be drawn by 

 gravity into one of the hernial orifices by the connection of its e.xtraperitoneal 

 portion with the subperitoneal fat with which it is in close contact. The bladder 

 "diverticulum," thus formed, is a result, not a cause of the hernia, and in 75 per 

 cent, of cases includes only the extraperitoneal bladder-wall. As vesical dilatation 

 and atony are usually the result of obstructive disease, — most common in elderly 

 males, — and as abdominal hernia is frequent during late middle life (page 1762;, it 

 will be understood why 75 per cent, of cases of hernia of the bladder occur in men 

 (irrespective of cases of vaginal cystocele) and more than 50 per cent, in persons 

 over fifty years of age. In old herniae there has, of course, been an opportunity 

 for the stretching and elongation of the bladder-wall essential for the production of 

 the cystocele. 



The laxity of the attachments of the bladder to surrounding structures necessi- 

 tated by its changes in size or capacity favors the production of hernia. 



Effects of Distention. — The cavity of the normal empty bladder, which is strongly 

 contracted during life, presents little more than a narrow, cleft-like lumen, with a 

 gentle upward curve, continuous with that of the urethra. As it distends the 

 pyriform bladder becomes oval in shape, its summit rises from the pelvis above the 

 symphysis pubis, its anterior wall becomes applied to the inner surface of the ab- 

 dominal wall in the hypogastric region, and the whole organ assumes an ovoid shape 

 or, in extreme distention, one nearly spherical. Its normal capacity in the adult is 

 about one pint, but the looseness of the submucosa over the greater part of its sur- 

 face, the reticular arrangement of its muscle-fibres, and the yielding nature of the 

 structures by which it is surrounded when it has risen from the pelvis permit of 

 its enormous distention, especially as a result of slowly increasing obstructive dis- 



