MYOMA OF THE UTEKUS. 449 



With the enlargement of an interstitial myoma, the mucous 

 layer of the wall of the uterus will be separated from the serous, 

 layer. The entire uterus increases in size, and the cavity of the 

 body is lengthened. The uterine and ovarian arteries become 

 considerably enlarged to supply the new growth. The veins in 

 the broad ligament are correspondingly dilated, and large venous 

 sinuses are formed in the capsule of the tumour. 



When the myoma develops in that part of the uterine wall 

 close to the broad ligament, particularly the region of the 

 supravaginal cervix, it may extend outwards and become intra- 

 ligamentous. 



The subperitoneal variety tends to become pedunculated, and 

 as a result of traction or violence the pedicle may be twisted or 

 actually torn through. When the subserous myoma is formed 

 from the anterior aspect of the uterus, it not infrequently 

 carries the vesico-uterine fold of peritoneum upwards, and 

 now and again the bladder will be stretched out on the surface 

 of the tumour, and the ureter on one or both sides considerably 

 displaced. 



When the myoma commences beneath the uterine mucosa, it 

 tends to become extruded into the cavity of the organ, and may 

 present as a pedunculated growth. The uterus will endeavour 

 to extrude what is really a foreign body, and consequently the 

 pedicle will become more and more lengthened, and the vascular 

 supply considerably diminished ; hence it is that gangrene of the 

 myoma frequently occurs. 



The enlargement of the whole uterus tends to produce pressure 

 upon and displacement of the surrounding structures. Inter- 

 ference with micturition and defaecation are by no means 

 uncommon. Haemorrhoids may also be induced by the inter- 

 ference with the return of blood from the mucous membrane of 

 the rectum. Pressure upon nerve trunks, where the growth 

 occupies and is somewhat impacted in the pelvic cavity, will 

 often induce very severe pain. Pressure upon the ureters may 

 result in obstruction and dilatation of the tubes, and subsequent 

 hydronephrosis and even uraemia. 



C.A.A. 29 



