308
CHAPTER 26
part of the urethra, are the outer and inner longitudinal fibres and transverse bundles of
the bladder base and also elastic tissues, (c) Circular bundles surrounding the internal
urethral orifice from the trigonal muscle. The vesical neck also contains striated muscle
fibres deriving from the external urethral sphincter. Bors
et al.
(1954) found striated
muscle fibres at the bladder neck in 19 out of 20 resections of the bladder neck but only
at the anterior commissure (12 o'clock).
The closing or fluid retention mechanism has been the subject of controversy for
some time. The traditional concept of the existence of a true annular internal vesical
sphincter (Uhlenhut
et al.,
1953) has been denied in recent years in particular by Wood-
burne (1960, 1967) on account of his studies on macerated preparations after stripping
the bladder from its adventitia. Fig. 136 demonstrates Woodburne's findings. He con
firmed the views of previous authors (Le Gros Clark, 1883; Griffith, 1895) tnat there is no
specific smooth muscle sphincter at the vesical neck. On the contrary, there is a contin
uity of bladder and urethra and the arrangement of the detrusor fibres are such as to
open mechanically the proximal part of the vesical neck. However, recently Ichim &
Burghele (1970), who studied the fibres of the detrusor by a 'transparency method' on
human bladders 24 hours after death, came to the conclusion that there exists a smooth
internal sphincter. In these experiments the upper pole of the bladder was opened, a cold
light cystoscope introduced and the bladder was filled with saline. Through the trans
parence of the illuminated bladder, the course of the detrusor fibres as well as the
anatomical structures of the trigone and the bladder floor, with its 'trigonal mouthpiece'
forming a morphological unit with a rich vascular supply, can be studied from the
outside. These authors found of special interest the annular formation of the bladder
orifice which plays the role of a smooth sphincter merging posteriorly with the trigone.
Moreover, one can see with this method the elastic connective tissue which serves as a
support and insertion point of the smooth muscle fibres and completes the muscular-
connective tissue ring of the bladder floor. This ring has the function of a smooth
sphincter. In the area of the ring the mucosa is fixed to the deep layers.
THE LYMPHATIC SYSTEM OF THE BLADDER
Since Masgagni (1787) and Cruikshank (1790) described the lymphatic vessels in the
bladder, the problem of localization and distribution of the lymph vessels in the bladder
has been the subject of repeated discussion in the literature. Although the views expressed
are controversial, the majority of histologists agree that neither the urothelium nor the
submucosa contain lymph vessels and that the lymphatic system is localized in the muscle
layers (Renyi-Vamos, 1960). Lymph vessels from the upper vesical wall cross the arteria
obturatoria and its accompanying veins and join lymph glands which are situated along
the arteria hypogastrica and arteria iliaca externa. The lymph vessels originating from
the bladder neck join together with those from the prostate and seminal vesicles, the
lower lumbar lymph glands. Knowledge of this anatomical distribution of the lymph
gland system helps to understand the course of infection within the bladder and urogenital
tracts.
