IMPOTENCE IN THE MALE:
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by
Prof Peter H C Lim,
AM, MBBS, MMed(Surgery), D.Urol(Lond).,
Head &,
Senior Consultant Urological Surgeon,
Division of Urology,
Toa Payoh Hospital.


Introduction:
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This is the inability to obtain or maintain an
erection suitable for sexual intercourse & is common in men
of all ages & especially so in the elderly. Psychological
Impotence can be caused by anxiety, depression, tension,
guilt, stress, marital problems & fear of failure to perform
sexually. Physical impotence occurs when disease or injury
affects the nerves, blood vessels or hormones that control
erectile ability. Diabetes & hardening of the arteries eg. in
high blood pressure or heart disease, constitute the
commonest causes. Others include pelvic surgery, spinal cord
injury, prostate infections, drug abuse. alcoholism, smoking
& as a result of the side effects of some medications.

Diagnosis:
_________
The Urologist takes a complete medical & sexual
history including the presentation & nature of the patient's
impotence, sexual experience, performance & medical
background. The patient's partner should be included in the
assessment of the problem. A full Psychological Screening to
uncover feelings of guilt, frustration, embarassment, fear &
other problems inimical to the emotional health of the couple
is conducted. If a diagnosis is still not forthcoming, blood
sexual hormone levels are estimated & a simple dynamic
papaverine injection test is done. A special "sleep" test to
examine the quality of nocturnal (night-time) erections
follows which measures the number of erections & the quality,
duration & amplitude of these that should occur in men during
deep sleep. In selected patients suspected of "venous leak"
impotence i.e. impotence caused by a condition equivalent to
varicose veins of the legs but occurring in this instance in
the veins drainning the penis, a special Xray study called
Cavernosography with cavernosometry is done. In young men
whose impotence is caused by damage to the arterial supply of
the penis due to an accident, an Arteriogram Xray is done.
Finally, Nerve Conduction Studies will demonstrate difficult
nerve related causes if the above tests are still
insufficient.



Medical Treatment:
__________________
Counselling helps for most psychogenic
problems. This is most effective when both partners
participate. Low male hormones levels are found in men
undergoing andropause (male equivalent of the menopause in
women). Replacement therapy either orally or by injection can
often restore potency. On the other hand, elevated levels of
another hormone called prolactin can cause impotence & is
easily treated by a special medication.
Other medicines eg. Yohimbine may restore
erections in approximately 20% of patients but require
medical practitioner close surveillance. The most effective
albeit a little painful way of restoring erections on demand
is by a special Self-Injection Programme of injection by the
patient himself of a medication called papaverine or
prostaglandin into the penis when the need arises. The
primary disadvantage of this method is a small risk of a
prolonged painful erection following the injection which can
only be corrected by injecting an antidote by a urologist.
This is not common but nonetheless the patient must be ready
to return to the hospital for this antidote should the
erection lasts longer than 4 hours.
A special device to create a vacuum which
causes an erection is now available in S'pore which is quite
effective. However it is not suitable for some patients with
various penile injuries, sickle cell disease, leukemia,
pelvic infections or blood clotting problems & it requires
some dexterity & strength to apply, operate & remove & has a
25 minute maximum time limit for each use.

Surgical Treatment:
__________________
For "Venous Leak" impotence, removal of the
offending veins gives a cure in 60% of cases with some degree
of improvement in the rest. Microsurgical reconstruction of
the arterial blood supply is indicated only for the young man
with blocked arteries due to trauma. When successful, these
procedures result in normal, natural penile erections.
For most patients especially those older
men with diabetes & blood pressure/heart problems, the
implantation of a penile prosthesis is usually the only sure
way of restoring erections. These implants produce erections
but will not affect sensation, ejaculation or orgasm. The
overall success rate with these devices is about 90%. Three
main types are available: The semi-rigid or malleable, the
self-contained inflatable or the multi-component inflatable.
The last named gives the most natural & effective results &
is also the most expensive. All surgical implants carry a
small risk of infection but the main patient at risk is the
diabetic patient. Also like all artificial devices,
mechanical failure may occur(although this is not common) &
thus may require revisional surgery.