Henry Gray (18251861). Anatomy of the Human Body. 1918.
most common form is where the deficiency is confined to the glans penis. The urethra ends at the point where the extremity of the prepuce joins the body of the penis, in a small valve-like opening. The prepuce is also cleft on its under surface and forms a sort of hood over the glans. There is a depression on the glans in the position of the normal meatus. This condition produces no disability and requires no treatment. In more severe cases the cavernous portion of the urethra is cleft throughout its entire length, and the opening of the urethra is at the point of junction of the penis and scrotum. The under surface of the penis in the middle line presents a furrow lined by a moist mucous membrane, on either side of which is often more or less dense fibrous tissue stretching from the glans to the opening of the urethra, which prevents complete erection taking place. Great discomfort is induced during micturition, and sexual connection is impossible. The condition may be remedied by a series of plastic operations. The worst form of this condition is where the urethra is deficient as far back as the perineum, and the scrotum is cleft. The penis is small and bound down between the two halves of the scrotum, so as to resemble an hypertrophied clitoris. The testes are often retained. The condition of parts, therefore, very much resembles the external organs of generation of the female, and many children the victims of this malformation have been brought up as girls. The halves of the scrotum, deficient of testes, resemble the labia, the cleft between them looks like the orifice of the vagina, and the diminutive penis is taken for an enlarged clitoris. There is no remedy for this condition.
A much more uncommon form of malformation is where there is an apparent deficiency of the upper wall of the urethra; this is named epispadias. The deficiency may vary in extent; when it is complete the condition is associated with extroversion of the bladder. In less extensive cases, where there is no extroversion, there is an infundibuliform opening into the bladder. The penis is usually dwarfed and turned upward, so that the glans lies over the opening. Congenital stricture is also occasionally met with, and in such cases multiple strictures may be present throughout the whole length of the cavernous portion.
3b. 5. The Female Urethra
The female urethra(Fig. 1139) is a narrow membranous canal, about 4 cm. long, extending from the internal to the external urethral orifice. It is placed behind the symphysis pubis, imbedded in the anterior wall of the vagina, and its direction is obliquely downward and forward; it is slightly curved with the concavity directed forward. Its diameter when undilated is about 6 mm. It perforates the fasciæ of the urogenital diaphragm, and its external orifice is situated directly in front of the vaginal opening and about 2.5 cm. behind the glans clitoridis. The lining membrane is thrown into longitudinal folds, one of which, placed along the floor of the canal, is termed the urethral crest. Many small urethral glands open into the urethra.
Structure.The urethra consists of three coats: muscular, erectile, and mucous.
The muscular coat is continuous with that of the bladder; it extends the whole length of the tube, and consists of circular fibers. In addition to this, between the superior and inferior fasciæ of the urogenital diaphragm, the female urethra is surrounded by the Sphincter urethræ membranaceæ, as in the male.
A thin layer of spongy erectile tissue, containing a plexus of large veins, intermixed with bundles of unstriped muscular fibers, lies immediately beneath the mucous coat.
The mucous coat is pale; it is continuous externally with that of the vulva, and internally with that of the bladder. It is lined by stratified squamous epithelium, which becomes transitional near the bladder. Its external orifice is surrounded by a few mucous follicles.
3c. The Male Genital Organs
(Organa Genitalia Virilia)
The male genitals include the testes, the ductus deferentes, the vesiculæ seminales, the ejaculatory ducts, and the penis, together with the following accessory structures, viz., the prostate and the bulbourethral glands.
1. The Testes and their Coverings (Figs. 1143,1144,1145)The testes are two glandular organs, which secrete the semen; they are suspended in the scrotum by the spermatic cords. At an early period of fetal life the testes are contained in the abdominal cavity, behind the peritoneum. Before birth they