THE VAGINA 



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the vaginal portion of the cervix uteri. The roof of the space is formed by the 

 reflection of the vagina upon the cervix and is termed the fornix. Owing to the 

 greater length of the posterior wall of the vagina the portion of the circular space 

 below the posterior fornix is considerably deeper than that below the anterior. 



In its ordinary condition the lumen of the vaginal canal is a fissure, which in 

 transverse section resembles the form of the letter H with a rather long trans- 

 verse bar (fig. 1036). On both the anterior and the posterior wall there is in the 

 median line a well-marked longitudinal ridge, the columna rugarum., which is 

 especially distinct in the lower part of the anterior wall, where it lies immediately 

 beneath the urethra and forms what is known as the urethral carina. From both 

 columnse other ridges pass laterally and upward on either side, forming the 

 rugce vaginales. Both these and the columnae diminish in distinctness with ad- 

 vance in age and with successive parturitions. Toward its lower end the vagina 

 traverses the urogenital trigone, being much less dilatable in this region than 

 elsewhere, and it opens below into the vestibule of the external genitalia. Its 

 orifice is partially closed by a fold of connective tissue, rich in blood-vessels, and 

 lined on both surfaces by mucous membrane. This membrane, known as the 



Fig. 1036. — Hokizontal Section of Vagina and adjacent Structures. (After Henle.) 



Urethra' 



Vagina 



Levator ani 



Rectum 



hymen, has usually a somewhat semilunar form, surrounding the posterior border 

 of the orifice, but it may take the form of a circular curtain pierced by one or several 

 apertures. 



It varies greatly in strength and development and although it is nearly always ruptured 

 by the first act of sexual congress, it may remain unbroken until parturition. Rarely it takes 

 the form of a complete imperforate curtain and may necessitate a surgical operation at the 

 commencement of the menstrual periods. After rupture the remains of the hymen persist as 

 small lobed or wart-like structures, the cariinculce hymenales, around the vaginal orifice. 



Relations. — The uppermost part of the posterior wall of the vagina is in 

 relation with the peritoneum forming the floor of the recto-uterine pouch (of 

 Douglas), but elsewhere the canal is entirely below the floor of the peritoneal 

 cavity. Posteriorly it rests almost directly upon the rectum (fig. 1036), and the 

 contents of that viscus may be readily felt through its walls. Anteriorly it is in 

 intimate relation with the urethra and the posterior wall of the bladder (figs. 

 1034, 1036), while laterally it is crossed obliquely in its upper third by the ureters 

 as they pass to the base of the bladder, and in its lower two-thirds by the edges of 

 the anterior portion of the levatores ani. The duct of Gartner, the remains of the 

 lower portion of the Wolffian duct, may occasionally be found at the side of the 



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