The diseases of the male urethra / by R.W. Stewart, M.D., M.R.C.S.

  • Stewart, R. W. (Robert W.), 1861-
Date:
1896
Catalogue details

Licence: Public Domain Mark

Credit: The diseases of the male urethra / by R.W. Stewart, M.D., M.R.C.S. Source: Wellcome Collection.

Provider: This material has been provided by University of Bristol Library. The original may be consulted at University of Bristol Library.

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    vesical termination, thus saving- the delicate ureters and secreting- portion of the kidneys from injurious disten- tion during the act of urination. When the bladder is distended the tension of its wall acting on the vesie;il orifice of the urethra overcomes the sphincteric action of the internal sphincter, and the urine leaks into the pos- terior urethra, which in this condition virtually forms u portion of the bladder, and for this reason is often called the neck of the bladder (Fig. 3). The further progress of the urine is barred by the sphincteric action of two muscles surrounding the urethra at, and immediately in front of, the apex of the prostate gland. The first is called the sphincter vesica? externus. It is a band of striated and non-striated muscular fibres, situated at the apex of the prostate. The second is called the compressor ure- thra?. It is a voluntary or striated muscle, and lies be- tween the two layers of the triangular ligament, to which, and to the ischio-pubic rami on either side, it is attached. Weaving itself in various directions—above, below, and around the membranous portion of the urethra—it forms, with the adjacent circular muscle situated at the apex of the prostate, the external sphincter of the bladder. This sphincter is much more powerful than the internal sphincter, and offers a greater resistance to the passim <■ of fluids or instruments. It is therefore the principal barrier to the passage forward of the urine from the bladder, and to the passage backward of urethral secre- tions or injections, and to this fact the clinical division of the urethra into an anterior and a posterior portion is due. Fie;. 3 shows the situation of these muscles and the ef- fect on the posterior urethra of a distended bladder, the empty bladder being represented by the dotted lines.