Magnus Johannesson

P848 A randomised trial of the effect of oestrogen and testosterone on economic behaviour

from the bladder neck down to the urogenital diaphragm. It is lined by urothelium. The muscle fibers intermingle with the collagen fibers in the middle of the cylinder’s thickness. The muscle layer is controlled by alpha-sympathetic nerves T10-L2, and is connected above with the detrusor muscle. The IUS is intimately lying on the anterior vaginal wall. ii. The acquired factor: (Second stage of micturition) (5). This is an acquired behavior gained by learning and training in early childhood how to maintain a high alpha sympathetic tone at the IUS keeping it closed all the time until voiding is needed and/or desired. Imaging using US and MRI had been tried by some distinguished scientists, to see the state of the bladder neck, the urethra, and their position and their relation to the symphysis pubis and the pelvic floor (19–23). A tough and a strong anterior vaginal wall is an essential support for keeping the vagina in its upward position, and is a major support for the intimately overlying IUS and the lower part of the posterior wall of the urinary bladder. A weak overstretched and flabby anterior vaginal wall will fall down (prolapse), with its overlying IUS and lower part of the posterior wall of the urinary bladder. The strength and the toughness of the vaginal wall depend on its rich compact collagen fibers. The compact tough collagen bundles are also essential elements of keeping the vagina in its normal upward position without descending or falling down. As an example, a hard-cover book will stand upright on a shelf, while a paper-cover book will fall down. The effects of childbirth trauma on the pelvic organs have been the subject of many excellent research subjects of many distinguished authors. (24–30) Prolonged labor, difficult labor, multiple frequent labors, and operative vaginal deliveries cause stretching, attenuation, split and actual lacerations of the collagen bundles of the vagina causing weakness and laxity of the vaginal wall. After menopause, there is further slowly progressive collagen attenuation caused by ovarian hormone deficiency, which will aggravate the vaginal wall weakness, and the weakness of the IUS. Another factor which may add to the etiology of the vaginal wall weakness and the IUS weakness is repeated vaginal and urinary infections which will cause degeneration of the collagen. The weakness and rupture of the vaginal collagen sheet will manifest itself mostly in the transverse axis of the vagina. This is seen clinically and on imaging: 1. At first, there will be loss of the nulliparous H-shape vagina which changes into a transverse slit in parous women. (Figure: 10). 2. Then, further weakness, will lead to loss of vaginal rugae; the vaginal wall will be smooth without folds as can be seen clinically. 3. Further weakness and rupture of the vaginal collagen will induce vaginal wall redundancy and descent. In the transverse axis of the vagina, the central midsegment suffers more damage than the periphery which is a mechanical effect. The stretching, attenuation, degeneration, split and lacerations which affect the anterior vaginal wall will, without doubt, affect the intimately overlying IUS causing rupture of its posterior wall. This will lead to a defective weak IUS with lowered UCP, and subsequent urinary incontinence on provocation. In patients suffering SUI, the IUS is torn and disrupted with echolucent areas. Depending on the level and extent of the damage along the cylinder there are different morphological changes. When the damage affects mainly the upper part there will be funneling of the urinary bladder neck with loss of the urethro-vesical angle and apparent descent of the urinary bladder neck and shortening of the urethra. Urine will enter the upper part of the urethra on sudden increase of intra-vesical pressure giving sensation of sudden desire to void, detrusor overactivity (DO). When the damage affects mainly the lower part there will be a flask-shape appearance, and genuine SUI ensues. When the damage affects the entire length there will be collapse of the urethra, with apparent shortening and mixed type of urinary incontinence.