405 



Nachdruck verboten. 



The Form of the Empty Bladder. 



By A. Francis Dixon, University College, Cardiff. 



With 2 Figures. 



An examination of the pelvic viscera, in subjects in whom the 

 various organs have been hardened in situ by strong solutions of 

 formaline, establishes the fact that the empty bladder possesses a very 

 definite shape or form. In such subjects the shape of the bladder is 

 found to resemble that of an inverted tetrahedron. The apex of the 

 tetrahedron is truncated in the male and corresponds to the point 

 where the urethra leaves the organ, while the three basal angles of 

 the tetrahedron correspond to the bladder apex (attachment of the 

 urachus) and to the points where the two ureters reach the bladder 

 (see fig. 1). The three surfaces which approach each other at the 

 urethral orifice are separated from one another by rounded borders, 

 but the superior surface of the organ which looks into the pelvic 

 cavity and corresponds to the base of the inverted tetrahedron, is 

 sharply marked off by a distinct posterior border and by lateral 

 borders. The sharply marked lateral border of the empty bladder 

 runs on each side from the bladder apex to the point where the 

 corresponding ureter reaches the organ (or lateral angle). When 

 the bladder is in situ this border lies against the pelvic wall, just 

 above the level of the white line of the pelvic fascia. The peritoneum 

 is reflected from the bladder on to the side wall of the pelvis along 

 the lateral border. The vas deferens, as it passes backwards on the 

 pelvic wall, lies parallel to, but at a considerably higher level than 

 the lateral border of the bladder. (It often lies as much as 1 to 

 l 1 / 2 inches above it.) The posterior border of the bladder lies between 

 the lateral angles, or points where the ureters reach the organ. The 

 superior surface of the bladder, which is bounded by these three 

 borders, has the form of a triangle enclosed by sides which are curved 

 somewhat outwards. When the organ is firmly contracted this sur- 

 face bulges into the pelvic cavity, forming a somewhat flask-shaped 

 convexity. The neck of the flask corresponds in position to the 

 bladder apex. 



