Impotence
Article Abstract:
Ten million American men are estimated to be impotent. The condition is thus common and often has a profound effect on the fabric of the affected individual's life. The anatomy, physiology, and pharmacology of penile erection and the available treatments for impotence are reviewed. Erection occurs when the smooth muscle in the wall of helicine arteries and in specialized erectile tissue of the penis relax and allow the vascular spaces to become engorged with blood; the engorgement in turn presses the peripheral veins that drain the penis against an unyielding connective tissue envelope, the tunica albuginea, at the periphery of the penis. The increase in pressure causes the penis to become rigid. Erection can be triggered by psychological stimuli as well as by localized reflex activity from genital stimulation. The main neurological mechanism is under the control of the parasympathetic division of the autonomic nervous system which leaves the spinal cord in the lumbosacral area. Ejaculation, under control of the sympathetic division of the autonomic nervous system, acts to terminate the erection mechanism. Erection physiology is not simple, and psychological factors, drugs, changes in endocrine function, vascular anomalies, and other medical conditions including tumors and diabetes can all affect erection adversely. A procedure for diagnosis is presented that allows the physician to separate the various reasons for a patient's impotence. Many forms of treatment have recently been developed including psychotherapeutic approaches, direct injections of drugs into the penis to produce erections, vascular surgical methods, implantation of artificial prostheses, and the use of external suction and restrictive elastic bands around the penile base. The article also includes an extensive review of the literature.
Publication Name: The New England Journal of Medicine
Subject: Health
ISSN: 0028-4793
Year: 1989
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Sperm morphology, motility, and concentration in fertile and infertile men
Article Abstract:
It may be very difficult to diagnose male infertility by analyzing the number, movement, or shape of sperm. In a study of 765 infertile men and 696 fertile men, sperm characteristics varied considerably and there was a substantial overlap in sperm quality between both groups.
Publication Name: The New England Journal of Medicine
Subject: Health
ISSN: 0028-4793
Year: 2001
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Sex, hormones, and hysterectomies
Article Abstract:
A testosterone patch may benefit women with impaired sexual function after surgical menopause as long as a dose can be found that is effective but has few unwanted side effects. Surgical menopause occurs when women have their ovaries removed before natural menopause occurs.
Publication Name: The New England Journal of Medicine
Subject: Health
ISSN: 0028-4793
Year: 2000
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